TY  - JOUR
AB  - Mammalian cryptochrome 1 (CRY1) is a central player in the circadian transcription-translation feedback loop, crucial for maintaining a roughly 24-h rhythm. CRY1 was suggested to also function as a blue-light photoreceptor in humans and has been found to be expressed at the mRNA level in various cell types of the inner retina. However, attempts to detect CRY1 at the protein level in the human retina have remained unsuccessful so far. Using various C-terminal specific antibodies recognizing full-length CRY1 protein, we consistently detected selective labeling in the outer segments of short wavelength-sensitive (SWS1, "blue") cone photoreceptor cells across human, bonobo, and gorilla retinae. No other retinal cell types were stained, which is in contrast to what would be expected of a ubiquitous clock protein. Subcellular fractionation experiments in transfected HEK cells using a C-terminal specific antibody located full-length CRY1 in the cytosol and membrane fractions. Our findings indicate that human CRY1 has several different functions including at least one nonclock function. Our results also raise the likely possibility that several different versions of CRY1 exist in humans. We suggest that truncation of the C-terminal tail, maybe to different degrees, may affect the localization and function of human CRY1.
AU  - Bartölke, R.*
AU  - Nießner, C.*
AU  - Reinhard, K.*
AU  - Wolfrum, U.*
AU  - Meimann, S.*
AU  - Bolte, P.*
AU  - Feederle, R.
AU  - Mouritsen, H.*
AU  - Dedek, K.*
AU  - Peichl, L.*
AU  - Winklhofer, M.*
C1  - 74198
C2  - 57391
CY  - 111 River St, Hoboken 07030-5774, Nj Usa
TI  - Full-length cryptochrome 1 in the outer segments of the retinal blue cone photoreceptors in humans and great apes suggests a role beyond transcriptional repression.
JO  - FASEB J.
VL  - 39
IS  - 8
PB  - Wiley
PY  - 2025
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Brown adipose tissue (BAT) is a key thermogenic organ, whose activation in response to cold environmental temperatures and β-adrenergic stimulation requires the proper function of the NCOR/HDAC3 corepressor complex in brown adipocytes. The NCOR/HDAC3 complex is large and multi-component, including the transducin beta-like 1 (TBL1) and TBL1-related 1 (TBLR1) proteins. Loss of TBL1 in the hepatocytes and TBLR1 in the white adipocytes has been shown to impair fasting- and β-adrenergic-induced lipolysis. However, their roles in BAT thermogenesis remain unknown. Here, we report that deletion of TBLR1 alone in brown adipocytes does not impair the adaptive thermogenic response to prolonged cold exposure. In contrast, simultaneous deletion of TBL1 and TBLR1 dampens β-adrenergic-induced lipolysis and mitochondrial respiration in cultured mouse brown adipocytes. Transgenic mice with UCP1-Cre mediated double deletion of TBLR1 and TBL1 exhibit reduced whole-body energy expenditure during prolonged cold exposure, lower core body temperature, increased appearance of unilocular adipocytes in BAT, and suppressed expression of metabolic and myogenic PRDM16 target genes. Also, we present some evidence that TBLR1 and TBL1 interact with HDAC3 and PRDM16 in brown adipocytes, potentially suggesting a direct involvement in the PRDM16-controlled transcriptional program. These findings identify the TBLR1/TBL1 complex as a critical regulator of BAT adaptation to prolonged cold and systemic energy homeostasis, shedding light on the context-dependent functions of corepressor complexes.
AU  - Köker, S.C.
AU  - Tsokanos, F.-F.
AU  - El-Merahbi, R.
AU  - Jha, A.K.
AU  - Cicatelli, K.
AU  - Weber, P.
AU  - Mhamane, A.
AU  - Kaltenecker, D.
AU  - Morigny, P.
AU  - Loft, A.
AU  - Klepac, K.
AU  - Maida, A.
AU  - Molocea, C.-E.
AU  - Hass, D,
AU  - Vogl, E.S.
AU  - Alfaro, A.J.
AU  - Sun, W.*
AU  - Zitzelsberger, H.
AU  - Unger, K.
AU  - Szendrödi, J.*
AU  - Li, Y.*
AU  - Diaz, M.B.
AU  - Wolfrum, C.*
AU  - Bartelt, A.
AU  - Herzig, S.
AU  - Georgiadi, A.
C1  - 75332
C2  - 58172
CY  - 111 River St, Hoboken 07030-5774, Nj Usa
TI  - The TBLR1/TBL1 co-factor complex acts as a transcriptional checkpoint in the brown adipose tissue response to prolonged cold exposure.
JO  - FASEB J.
VL  - 39
IS  - 15
PB  - Wiley
PY  - 2025
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Hepatocellular carcinoma (HCC) is one of the most fatal and fastest growing malignancies. Recently, nonalcoholic steatohepatitis (NASH), characterized by liver steatosis, inflammation, cell injury (hepatocyte ballooning), and different stages of fibrosis, has emerged as a major catalyst for HCC. Because the STE20-type kinases, MST3 and MST4, have been described as critical molecular regulators of NASH pathophysiology, we here focused on determining the relevance of these proteins in human HCC. By analyzing public datasets and in-house cohorts, we found that hepatic MST3 and MST4 expression was positively correlated with the incidence and severity of HCC. We also found that the silencing of both MST3 and MST4, but also either of them individually, markedly suppressed the tumorigenesis of human HCC cells including attenuated proliferation, migration, invasion, and epithelial-mesenchymal transition. Mechanistic investigations revealed lower activation of STAT3 signaling in MST3/MST4-deficient hepatocytes and identified GOLGA2 and STRIPAK complex as the binding partners of both MST3 and MST4. These findings reveal that MST3 and MST4 play a critical role in promoting the progression of HCC and suggest that targeting these kinases may provide a novel strategy for the treatment of liver cancer.
AU  - Caputo, M.*
AU  - Xia, Y.*
AU  - Anand, S.K.*
AU  - Cansby, E.*
AU  - Andersson, E.*
AU  - Marschall, H.U.*
AU  - Königsrainer, A.*
AU  - Peter, A.
AU  - Mahlapuu, M.*
C1  - 68071
C2  - 54549
CY  - 111 River St, Hoboken 07030-5774, Nj Usa
TI  - STE20-type kinases MST3 and MST4 promote the progression of hepatocellular carcinoma: Evidence from human cell culture and expression profiling of liver biopsies.
JO  - FASEB J.
VL  - 37
IS  - 8
PB  - Wiley
PY  - 2023
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Fibroblast growth factor 23 (FGF23) is a main regulator of mineral homeostasis. Low and high circulating FGF23 levels are associated with bone, renal, cardiovascular diseases, and increased mortality. Understanding the factors and signaling pathways affecting FGF23 levels is crucial for the management of these diseases and their complications. Here, we show that activation of the Jak1/Stat3 signaling pathway leads to inflammation in liver and to an increase in hepatic FGF23 synthesis, a key hormone in mineral metabolism. This increased synthesis leads to massive C-terminal FGF23 circulating levels, the inactive C-terminal fragment, and increased intact FGF23 levels, the active form, resulting in imbalanced production and cleavage. Liver inflammation does not lead to activation of the calcineurin-NFAT pathway, and no signs of systemic inflammation could be observed. Despite the increase of active intact FGF23, excessive C-terminal FGF23 levels block the phosphaturic activity of FGF23. Therefore, kidney function and renal αKlotho expression are normal and no activation of the MAPK pathway was detected. In addition, activation of the Jak1/Stat3 signaling pathway leads to high calcitriol levels and low parathyroid hormone production. Thus, JAK1 is a central regulator of mineral homeostasis. Moreover, this study also shows that in order to assess the impact of high FGF23 levels on disease and kidney function, the source and the balance in FGF23 production and cleavage are critical.
AU  - Daryadel, A.*
AU  - Ruiz, P.A.*
AU  - Gehring, N.*
AU  - Stojanovic, D.*
AU  - Ugrica, M.*
AU  - Bettoni, C.*
AU  - Sabrautzki, S.
AU  - Pastor-Arroyo, E.M.*
AU  - Frey-Wagner, I.*
AU  - Lorenz-Depiereux, B.
AU  - Strom, T.M.*
AU  - Hrabě de Angelis, M.
AU  - Rogler, G.*
AU  - Wagner, C.A.*
AU  - Rubio-Aliaga, I.*
C1  - 61074
C2  - 49993
CY  - 111 River St, Hoboken 07030-5774, Nj Usa
TI  - Systemic Jak1 activation provokes hepatic inflammation and imbalanced FGF23 production and cleavage.
JO  - FASEB J.
VL  - 35
IS  - 2
PB  - Wiley
PY  - 2021
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Mineral homeostasis is regulated by a complex network involving endocrine actions by calcitriol, parathyroid hormone (PTH), and FGF23 on several organs including kidney, intestine, and bone. Alterations of mineral homeostasis are found in chronic kidney disease and other systemic disorders. The interplay between the immune system and the skeletal system is not fully understood, but cytokines play a major role in modulating calcitriol production and function. One of the main cellular signaling pathways mediating cytokine function is the Janus kinase (JAK)--signal transducer and activator of transcription (STAT) pathway. Here, we used a mouse model (Jak1S645P+/- ) that resembles a constitutive activating mutation of the Jak1/Stat3 signaling pathway in humans, and shows altered mineral metabolism, with higher fibroblast growth factor 23 (FGF23) levels, lower PTH levels, and higher calcitriol levels. The higher calcitriol levels are probably due to extrarenal calcitriol production. Furthermore, systemic Jak1/Stat3 activation led to growth impairment and skeletal alterations. The growth plate in long bones showed decreased chondrocyte proliferation rates and reduced height of terminal chondrocytes. Furthermore, we demonstrate that Jak1 is also involved in bone remodeling early in life. Jak1S645P+/- animals have decreased bone and cortical volume, imbalanced bone remodeling, reduced MAP kinase signaling, and local inflammation. In conclusion, Jak1 plays a major role in bone health probably both, directly and systemically by regulating mineral homeostasis. Understanding the role of this signaling pathway will contribute to a better knowledge in bone growth and in mineral physiology, and to the development of selective Jak inhibitors as osteoprotective agents.
AU  - Fuente, R.*
AU  - Gehring, N.*
AU  - Bettoni, C.*
AU  - Gil-Pena, H.*
AU  - Alonso-Durán, L.*
AU  - Michalke, B.
AU  - Santos, F.*
AU  - Wagner, C.A.*
AU  - Rubio-Aliaga, I.*
C1  - 62343
C2  - 50779
CY  - 111 River St, Hoboken 07030-5774, Nj Usa
TI  - Systemic Jak1 activation causes extrarenal calcitriol production and skeletal alterations provoking stunted growth.
JO  - FASEB J.
VL  - 35
IS  - 7
PB  - Wiley
PY  - 2021
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - High uncoupling protein 1 (Ucp1) expression is a characteristic of differentiated brown adipocytes and is linked to adipogenic differentiation. Paracrine fibroblast growth factor 8b (FGF8b) strongly induces Ucp1 transcription in white adipocytes independent of adipogenesis. Here, we report that FGF8b and other paracrine FGFs act on brown and white preadipocytes to upregulate Ucp1 expression via a FGFR1-MEK1/2-ERK1/2 axis, independent of adipogenesis. Transcriptomic analysis revealed an upregulation of prostaglandin biosynthesis and glycolysis upon Fgf8b treatment of preadipocytes. Oxylipin measurement by LC-MS/MS in FGF8b conditioned media identified prostaglandin E2 as a putative mediator of FGF8b induced Ucp1 transcription. RNA interference and pharmacological inhibition of the prostaglandin E2 biosynthetic pathway confirmed that PGE2 is causally involved in the control over Ucp1 transcription. Importantly, impairment of or failure to induce glycolytic flux blunted the induction of Ucp1, even in the presence of PGE2 . Lastly, a screening of transcription factors identified Nrf1 and Hes1 as required regulators of FGF8b induced Ucp1 expression. Thus, we conclude that paracrine FGFs co-regulate prostaglandin and glucose metabolism to induce Ucp1 expression in a Nrf1/Hes1-dependent manner in preadipocytes, revealing a novel regulatory network in control of Ucp1 expression in a formerly unrecognized cell type.
AU  - Gantert, T.*
AU  - Henkel, F.
AU  - Wurmser, C.*
AU  - Oeckl, J.*
AU  - Fischer, L.*
AU  - Haid, M.
AU  - Adamski, J.
AU  - Esser-von Bieren, J.
AU  - Klingenspor, M.*
AU  - Fromme, T.*
C1  - 61795
C2  - 50460
CY  - 111 River St, Hoboken 07030-5774, Nj Usa
TI  - Fibroblast growth factor induced Ucp1 expression in preadipocytes requires PGE2 biosynthesis and glycolytic flux.
JO  - FASEB J.
VL  - 35
IS  - 5
PB  - Wiley
PY  - 2021
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Cell adhesion is tightly controlled in multicellular organisms, for example, through proteolytic ectodomain shedding of the adhesion-mediating cell surface transmembrane proteins. In the brain, shedding of cell adhesion proteins is required for nervous system development and function, but the shedding of only a few adhesion proteins has been studied in detail in the mammalian brain. One such adhesion protein is the transmembrane protein endoglycan (PODXL2), which belongs to the CD34-family of highly glycosylated sialomucins. Here, we demonstrate that endoglycan is broadly expressed in the developing mouse brains and is proteolytically shed in vitro in mouse neurons and in vivo in mouse brains. Endoglycan shedding in primary neurons was mediated by the transmembrane protease a disintegrin and metalloprotease 10 (ADAM10), but not by its homolog ADAM17. Functionally, endoglycan deficiency reduced the branching of neurites extending from primary neurons in vitro, whereas deletion of ADAM10 had the opposite effect and increased neurite branching. Taken together, our study discovers a function for endoglycan in neurite branching, establishes endoglycan as an ADAM10 substrate and suggests that ADAM10 cleavage of endoglycan may contribute to neurite branching.
AU  - Hsia, H.E.*
AU  - Tüshaus, J.*
AU  - Feng, X.*
AU  - Hofmann, L.I.*
AU  - Wefers, B.
AU  - Marciano, D.K.*
AU  - Wurst, W.
AU  - Lichtenthaler, S.F.*
C1  - 62905
C2  - 51161
CY  - 111 River St, Hoboken 07030-5774, Nj Usa
TI  - Endoglycan (PODXL2) is proteolytically processed by ADAM10 (a disintegrin and metalloprotease 10) and controls neurite branching in primary neurons.
JO  - FASEB J.
VL  - 35
IS  - 9
PB  - Wiley
PY  - 2021
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Aging is accompanied by chronic, low-grade systemic inflammation, termed inflammaging, a main driver of age-associated diseases. Such sterile inflammation is typically characterized by elevated levels of pro-inflammatory mediators, such as cytokines, chemokines and reactive oxygen species causing organ damage. Lipid mediators play important roles in the fine-tuning of both the promotion and the resolution of inflammation. Yet, it remains unclear how lipid mediators fit within the concept of inflammaging and how their biosynthesis and function is affected by aging. Here, we provide comprehensive signature profiles of inflammatory markers in organs afflicted with inflammation of young and old C57BL/6 mice. We reveal an organ-specific footprint of inflammation-related cytokines, chemokines and lipid mediators, which are distinctively affected by aging. While some organs are characterized by a pronounced pro-inflammatory microenvironment and impaired resolution during aging, others display elevated levels of pro-resolving mediators or an overall decrease in inflammatory signaling. Our results demonstrate that it proves difficult to establish a unifying concept for alterations of immunomodulatory mediators as consequence of aging and that organ specificity needs to be considered. Moreover, our data imply that inclusion of lipid mediators into the concept of inflammaging provides a comprehensive tool to characterize the inflammatory microenvironment during aging on a broader and yet, more detailed scope.
AU  - Schädel, P.*
AU  - Troisi, F.
AU  - Czapka, A.*
AU  - Gebert, N.*
AU  - Pace, S.*
AU  - Ori, A.*
AU  - Werz, O.*
C1  - 61851
C2  - 50193
CY  - 111 River St, Hoboken 07030-5774, Nj Usa
TI  - Aging drives organ-specific alterations of the inflammatory microenvironment guided by immunomodulatory mediators in mice.
JO  - FASEB J.
VL  - 35
IS  - 5
PB  - Wiley
PY  - 2021
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Species have evolved unique mechanisms to combat the effects of oxidative stress inside cells. A particularly devastating consequence of an unhindered oxidation of membrane lipids in the presence of iron results in cell death, known as ferroptosis. Hallmarks of ferroptosis, including peroxidation of polyunsaturated fatty acids, are conserved among animals and plants, however, early divergence of an ancestral mammalian GPX4 (mGPX4) has complicated our understanding of mechanistic similarities between species. To this end, we performed a comprehensive phylogenetic analysis and identified that orthologous Arabidopsis GPXs (AtGPXs) are more highly related to mGPX4 than mGPX4 is to other mammalian GPXs. This high degree of conservation suggested that experimental substitution may be possible. We, therefore, ectopically expressed AtGPX1-8 in ferroptosis-sensitive mouse fibroblasts. This substitution experiment revealed highest protection against ferroptosis induction by AtGPX5, as well as moderate protection by AtGPX2, -7, and -8. Further analysis of these cells revealed substantial abatement of lipid peroxidation in response to pharmacological challenge. The results suggest that the presence of ancestral GPX4 resulted in later functional divergence and specialization of GPXs in plants. The results also challenge a strict requirement for selenocysteine activity and suggest thioredoxin as a potent parallel antioxidant system in both plants and mammals.
AU  - Song, W.*
AU  - Xin, S.
AU  - He, M.*
AU  - Pfeiffer, S.
AU  - Cao, A.*
AU  - Li, H.*
AU  - Schick, J.
AU  - Jin, X.*
C1  - 61929
C2  - 50517
CY  - 111 River St, Hoboken 07030-5774, Nj Usa
TI  - Evolutionary and functional analyses demonstrate conserved ferroptosis protection by Arabidopsis GPXs in mammalian cells.
JO  - FASEB J.
VL  - 35
IS  - 6
PB  - Wiley
PY  - 2021
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Sorafenib represents the current standard of care for patients with advanced-stage hepatocellular carcinoma (HCC). However, acquired drug resistance occurs frequently during therapy and is accompanied by rapid tumor regrowth after sorafenib therapy termination. To identify the mechanism of this therapy-limiting growth resumption, we established robust sorafenib resistance HCC cell models that exhibited mitochondrial dysfunction and chemotherapeutic crossresistance. We found a rapid relapse of tumor cell proliferation after sorafenib withdrawal, which was caused by renewal of mitochondrial structures alongside a metabolic switch toward high electron transport system (ETS) activity. The translation-inhibiting antibiotic tigecycline impaired the biogenesis of mitochondrial DNA-encoded ETS subunits and limited the electron acceptor turnover required for glutamine oxidation. Thereby, tigecycline prevented the tumor relapse in vitro and in murine xenografts in vivo. These results offer a promising second-line therapeutic approach for advanced-stage HCC patients with progressive disease undergoing sorafenib therapy or treatment interruption due to severe adverse events.
AU  - Meßner, M.*
AU  - Schmitt, S.*
AU  - Ardelt, M.A.*
AU  - Fröhlich, T.*
AU  - Müller, M.*
AU  - Pein, H.*
AU  - Huber-Cantonati, P.*
AU  - Ortler, C.*
AU  - Koenig, L.M.*
AU  - Zobel, L.*
AU  - Koeberle, A.*
AU  - Arnold, G.J.*
AU  - Rothenfußer, S.*
AU  - Kiemer, A.K.*
AU  - Gerbes, A.L.*
AU  - Zischka, H.
AU  - Vollmar, A.M.*
AU  - Pachmayr, J.*
C1  - 59643
C2  - 48929
CY  - 111 River St, Hoboken 07030-5774, Nj Usa
SP  - 11860-11882
TI  - Metabolic implication of tigecycline as an efficacious second-line treatment for sorafenib-resistant hepatocellular carcinoma.
JO  - FASEB J.
VL  - 34
IS  - 9
PB  - Wiley
PY  - 2020
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - The protease beta-site APP cleaving enzyme 1 (BACE1) has fundamental functions in the nervous system. Its inhibition is a major therapeutic approach in Alzheimer's disease, because BACE1 cleaves the amyloid precursor protein (APP), thereby catalyzing the first step in the generation of the pathogenic amyloid beta (Aβ) peptide. Yet, BACE1 cleaves numerous additional membrane proteins besides APP. Most of these substrates have been identified in vitro, but only few were further validated or characterized in vivo. To identify BACE1 substrates with in vivo relevance, we used isotope label-based quantitative proteomics of wild type and BACE1-deficient (BACE1 KO) mouse brains. This approach identified known BACE1 substrates, including Close homolog of L1 and contactin-2, which were found to be enriched in the membrane fraction of BACE1 KO brains. VWFA and cache domain-containing protein 1 (CACHD)1 and MAM domain-containing glycosylphosphatidylinositol anchor protein 1 (MDGA1), which have functions in synaptic transmission, were identified and validated as new BACE1 substrates in vivo by immunoblots using primary neurons and mouse brains. Inhibition or deletion of BACE1 from primary neurons resulted in a pronounced inhibition of substrate cleavage and a concomitant increase in full-length protein levels of CACHD1 and MDGA1. The BACE1 cleavage site in both proteins was determined to be located within the juxtamembrane domain. In summary, this study identifies and validates CACHD1 and MDGA1 as novel in vivo substrates for BACE1, suggesting that cleavage of both proteins may contribute to the numerous functions of BACE1 in the nervous system.
AU  - Rudan Njavro, J.*
AU  - Klotz, J.*
AU  - Dislich, B.*
AU  - Wanngren, J.*
AU  - Shmueli, M.D.*
AU  - Herber, J.*
AU  - Kuhn, P.H.*
AU  - Kumar, R.*
AU  - Koeglsperger, T.*
AU  - Conrad, M.
AU  - Wurst, W.
AU  - Feederle, R.
AU  - Vlachos, A.*
AU  - Michalakis, S.*
AU  - Jedlicka, P.*
AU  - Müller, S.A.*
AU  - Lichtenthaler, S.F.*
C1  - 57766
C2  - 47919
CY  - 9650 Rockville Pike, Bethesda, Md 20814-3998 Usa
SP  - 2465-2482
TI  - Mouse brain proteomics establishes MDGA1 and CACHD1 as in vivo substrates of the Alzheimer protease BACE1.
JO  - FASEB J.
VL  - 34
IS  - 2
PB  - Federation Amer Soc Exp Biol
PY  - 2020
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Loss-of-function variants in CCM1/KRIT1, CCM2, and CCM3/PDCD10 are associated with autosomal dominant cerebral cavernous malformations (CCMs). CRISPR/Cas9-mediated CCM3 inactivation in human endothelial cells (ECs) has been shown to induce profound defects in cell-cell interaction as well as actin cytoskeleton organization. We here show that CCM3 inactivation impairs fibronectin expression and consequently leads to reduced fibers in the extracellular matrix. Despite the complexity and high molecular weight of fibronectin fibrils, our in vitro model allowed us to reveal that fibronectin supplementation restored aberrant spheroid formation as well as altered EC morphology, and suppressed actin stress fiber formation. Yet, fibronectin replacement neither enhanced the stability of tube-like structures nor inhibited the survival advantage of CCM3(-/-) ECs. Importantly, CRISPR/Cas9-mediated introduction of biallelic loss-of-function variants into either CCM1 or CCM2 demonstrated that the impaired production of a functional fibronectin matrix is a common feature of CCM1-, CCM2-, and CCM3-deficient ECs.
AU  - Schwefel, K.*
AU  - Spiegler, S.*
AU  - Kirchmaier, B.C.*
AU  - Dellweg, P.K.E.*
AU  - Much, C.D.*
AU  - Pané-Farré, J.*
AU  - Strom, T.M.
AU  - Riedel, K.*
AU  - Felbor, U.*
AU  - Rath, M.*
C1  - 59328
C2  - 48782
CY  - 111 River St, Hoboken 07030-5774, Nj Usa
SP  - 9018-9033
TI  - Fibronectin rescues aberrant phenotype of endothelial cells lacking either CCM1, CCM2 or CCM3.
JO  - FASEB J.
VL  - 34
IS  - 7
PB  - Wiley
PY  - 2020
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Although we have shown that catecholamines suppress the activity of the Ubiquitin-Proteasome System (UPS) and atrophy-related genes expression through a cAMP-dependent manner in skeletal muscle from rodents, the underlying mechanisms remain unclear. Here, we report that a single injection of norepinephrine (NE; 1 mg kg(-1); s.c) attenuated the fasting-induced up-regulation of FoxO-target genes in tibialis anterior (TA) muscles by the stimulation of PKA/CREB and Akt/FoxO1 signaling pathways. In addition, muscle-specific activation of PKA by the overexpression of PKA catalytic subunit (PKAcat) suppressed FoxO reporter activity induced by (1) a wild-type; (2) a non-phosphorylatable; (3) a non-phosphorylatable and non-acetylatable forms of FoxO1 and FoxO3; (4) downregulation of FoxO protein content, and probably by (5) PGC-1 alpha up-regulation. Consistently, the overexpression of the PKAcat inhibitor (PKI) up-regulated FoxO activity and the content of Atrogin-1 and MuRF1, as well as induced muscle fiber atrophy, the latter effect being prevented by the overexpression of a dominant negative (d. n.) form of FoxO (d.n.FoxO). The sustained overexpression of PKAcat induced fiber-type transition toward a smaller, slower, and more oxidative phenotype and improved muscle resistance to fatigue. Taken together, our data provide the first evidence that endogenous PKA activity is required to restrain the basal activity of FoxO and physiologically important to maintain skeletal muscle mass.
AU  - Silveira, W.A.*
AU  - Machado, J.
AU  - Lautherbach, N.*
AU  - Lustrino, D.*
AU  - Paula-Gomes, S.*
AU  - Pereira, M.G.*
AU  - Miyabara, E.H.*
AU  - Sandri, M.*
AU  - Kettelhut, I.C.*
AU  - Navegantes, L.C.*
C1  - 59890
C2  - 49101
CY  - 111 River St, Hoboken 07030-5774, Nj Usa
SP  - 12946-12962
TI  - cAMP-dependent protein kinase inhibits FoxO activity and regulates skeletal muscle plasticity in mice.
JO  - FASEB J.
VL  - 34
IS  - 9
PB  - Wiley
PY  - 2020
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - In Type 1 Diabetes Mellitus (T1DM), leukocyte infiltration of the pancreatic islets and the resulting immune-mediated destruction of beta cells precede hyperglycemia and clinical disease symptoms. In this context, the role of the pancreatic endothelium as a barrier for autoimmunity- and inflammation-related destruction of the islets is not well studied. Here, we identified Robo4, expressed on endothelial cells, as a regulator of pancreatic vascular endothelial permeability during autoimmune diabetes. Circulating levels of Robo4 were upregulated in mice subjected to the Multiple Low-Dose Streptozotocin (MLDS) model of diabetes. Upon MLDS induction, Robo4-deficiency resulted in increased pancreatic vascular permeability, leukocyte infiltration to the islets and islet apoptosis, associated with reduced insulin levels and faster diabetes development. On the contrary, in vivo administration of Slit2 in mice modestly delayed the emergence of hyperglycaemia and ameliorated islet inflammation in MLDS-induced diabetes. Thus, Robo4-mediated endothelial barrier integrity reduces insulitis and islet destruction in autoimmune diabetes. Our findings highlight the importance of the endothelium as gatekeeper of pancreatic inflammation during T1DM development and may pave the way for novel Robo4-related therapeutic approaches for autoimmune diabetes.
AU  - Troullinaki, M.
AU  - Chen, L.-S.*
AU  - Witt, A.*
AU  - Pyrina, I.*
AU  - Phieler, J.*
AU  - Kourtzelis, I.*
AU  - Chmelar, J.*
AU  - Sprott, D.*
AU  - Gercken, B.*
AU  - Koutsilieris, M.*
AU  - Chavakis, T.
AU  - Chatzigeorgiou, A.*
C1  - 57799
C2  - 48109
CY  - 9650 Rockville Pike, Bethesda, Md 20814-3998 Usa
SP  - 3336-3346
TI  - Robo4-mediated pancreatic endothelial integrity decreases inflammation and islet destruction in autoimmune diabetes.
JO  - FASEB J.
VL  - 34
IS  - 2
PB  - Federation Amer Soc Exp Biol
PY  - 2020
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - The glucocorticoid receptor (GR) represents the crucial molecular mediator of key endocrine, glucocorticoid hormone-dependent regulatory circuits, including control of glucose, protein, and lipid homeostasis. Consequently, aberrant glucocorticoid signaling is linked to severe metabolic disorders, including insulin resistance, obesity, and hyperglycemia, all of which also appear upon chronic glucocorticoid therapy for the treatment of inflammatory conditions. Of note, long-term glucocorticoid exposure under these therapeutic conditions typically induces glucocorticoid resistance, requiring higher doses and consequently triggering more severe metabolic phenotypes. However, the molecular basis of acquired glucocorticoid resistance remains unknown. In a screen of differential microRNA expression during glucocorticoid-dependent adipogenic differentiation of human multipotent adipose stem cells, we identified microRNA 29a (miR-29a) as one of the most down-regulated transcripts. Overexpression of miR-29a impaired adipogenesis. We found that miR-29a represses GR in human adipogenesis by directly targeting its mRNA, and downstream analyses revealed that GR mediates most of miR-29a's anti-adipogenic effects. Conversely, miR-29a expression depends on GR activation, creating a novel miR-29-driven feedback loop. miR-29a and GR expression were inversely correlated both in murine adipose tissue and in adipose tissue samples obtained from human patients. In the latter, miR-29a levels were additionally strongly negatively correlated with body mass index and adipocyte size. Importantly, inhibition of miR-29 in mice partially rescued the down-regulation of GR during dexamethasone treatment. We discovered that, in addition to modulating GR function under physiologic conditions, pharmacologic glucocorticoid application in inflammatory disease also induced miR-29a expression, correlating with reduced GR levels. This effect was abolished in mice with impaired GR function. In summary, we uncovered a novel GR-miR-29a negative feedback loop conserved between mice and humans, in health and disease. For the first time, we elucidate a microRNA-related mechanism that might contribute to GR dysregulation and resistance in peripheral tissues.-Glantschnig, C., Koenen, M., Gil-Lozano, M., Karbiener, M., Pickrahn, I., Williams-Dautovich, J., Patel, R., Cummins, C. L., Giroud, M., Hartleben, G., Vogl, E., Blüher, M., Tuckermann, J., Uhlenhaut, H., Herzig, S., Scheideler, M. A miR-29a-driven negative feedback loop regulates peripheral glucocorticoid receptor signaling.
AU  - Glantschnig, C.
AU  - Koenen, M.*
AU  - Gil Lozano, M.
AU  - Karbiener, M.*
AU  - Pickrahn, I.*
AU  - Williams-Dautovich, J.*
AU  - Patel, R.*
AU  - Cummins, C.L.*
AU  - Giroud, M.
AU  - Hartleben, G.
AU  - Vogl, E.S.
AU  - Blüher, M.*
AU  - Tuckermann, J.*
AU  - Uhlenhaut, N.H.
AU  - Herzig, S.
AU  - Scheideler, M.
C1  - 55481
C2  - 46297
SP  - 5924-5941
TI  - A miR-29a-driven negative feedback loop regulates peripheral glucocorticoid receptor signaling.
JO  - FASEB J.
VL  - 33
IS  - 5
PY  - 2019
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - The main objective of this work was to investigate whether mitochondrial fusion occurs in the skeletal muscle of well-trained athletes in response to high-intensity exercise. Well-trained swimmers (n = 9) performed a duration-matched sprint interval training (SIT) and high-intensity high-volume training (HIHVT) session on separate days. Muscle samples from triceps brachii were taken before, immediately after, and 3 h after the training sessions. Transmission electron microscopy (TEM) was applied to assess mitochondrial morphology. Moreover, expression of genes coding for regulators of mitochondrial fusion and fission were assessed by real-time quantitative PCR. In addition, mitofusin (MFN)2 and optic atrophy 1 (OPA1) were quantified by Western blot analysis. TEM analyses showed that mitochondrial morphology remained altered for 3 h after HIHVT, whereas SIT-induced changes were only evident immediately after exercise. Only SIT increased MFN1 and MFN2 mRNA expression, whereas SIT and HIHVT both increased MFN2 protein content 3 h after exercise. Notably, only HIHVT increased OPA1 protein content. Mitochondrial morphologic changes that suggest fusion occurs in well-adapted athletes during exercise. However, HIHVT appears as a more robust inducer of mitochondrial fusion events than SIT. Indeed, SIT induces a rapid and transient change in mitochondrial morphology.
AU  - Huertas, J.R.*
AU  - Ruiz Ojeda, F.J.
AU  - Plaza-Díaz, J.*
AU  - Nordsborg, N.B.*
AU  - Martín-Albo, J.*
AU  - Rueda-Robles, A.*
AU  - Casuso, R.A.*
C1  - 56729
C2  - 47235
CY  - 9650 Rockville Pike, Bethesda, Md 20814-3998 Usa
SP  - 12087-12098
TI  - Human muscular mitochondrial fusion in athletes during exercise.
JO  - FASEB J.
VL  - 33
IS  - 11
PB  - Federation Amer Soc Exp Biol
PY  - 2019
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Insufficient autophagy has been reported in idiopathic pulmonary fibrosis (IPF) lungs. Specific roles of autophagy-related proteins in lung fibrosis development remain largely unknown. Here, we investigated the role of autophagy marker protein microtubule-associated protein 1 light chain 3 beta (LC3B) in the development of lung fibrosis. LC3B(-/-) mice upon aging show smaller lamellar body profiles, increased cellularity, alveolar epithelial cell type II (AECII) apoptosis, surfactant alterations, and lysosomal and endoplasmic reticulum stress. Autophagosomal soluble N-ethylmaleimide-sensitive factor attachment protein receptor syntaxin 17 is increased in the AECII of aged LC3B(-/-) mice and patients with IPF. Proteasomal activity, however, remained unaltered in LC3B(-/- )mice. In vitro knockdown of LC3B sensitized mouse lung epithelial cells to bleomycin-induced apoptosis, but its overexpression was protective. In vivo, LC3B(-/-) mice displayed increased susceptibility to bleomycin-induced lung injury and fibrosis. We identified cathepsin A as a novel LC3B binding partner and its overexpression in vitro drives MLE12 cells to apoptosis. Additionally, cathepsin A is increased in the AECII of aged LC3B(-/-) mice and in the lungs of patients with IPF. Our study reveals that LC3B mediated autophagy plays essential roles in AECII by modulating the functions of proteins like cathepsin A and protects alveolar epithelial cells from apoptosis and subsequent lung injury and fibrosis.
AU  - Kesireddy, V.S.*
AU  - Chillappagari, S.*
AU  - Ahuja, S.*
AU  - Knudsen, L.*
AU  - Henneke, I.*
AU  - Graumann, J.*
AU  - Meiners, S.
AU  - Ochs, M.*
AU  - Ruppert, C.*
AU  - Korfei, M.*
AU  - Seeger, W.*
AU  - Mahavadi, P.*
C1  - 57287
C2  - 47709
CY  - 9650 Rockville Pike, Bethesda, Md 20814-3998 Usa
SP  - 12392-12408
TI  - Susceptibility of microtubule-associated protein 1 light chain 3 beta (MAP1LC3B/LC3B) knockout mice to lung injury and fibrosis.
JO  - FASEB J.
VL  - 33
IS  - 11
PB  - Federation Amer Soc Exp Biol
PY  - 2019
SN  - 0892-6638
ER  - 

TY  - JOUR
AU  - Mao, G.*
AU  - Qu, F.
AU  - Angell, J.P.*
AU  - St Croix, C.*
AU  - Dar, H.H.*
AU  - Tyurin, V.A.*
AU  - Ritov, V.B.*
AU  - Kapralov, A.A.*
AU  - Amoscato, A.A.*
AU  - Anthonymuthu, T.*
AU  - Mohammadyani, D.*
AU  - Yang, Q.*
AU  - Stockwell, B.R.*
AU  - Tyurina, Y.Y.*
AU  - Conrad, M.
AU  - Bayir, H.*
AU  - Kagan, V.E.*
C1  - 51773
C2  - 43360
CY  - Bethesda
TI  - Tocopherols and tocotrienols prevent lipoxygenase-driven phospholipid oxidation in ferroptosis.
JO  - FASEB J.
VL  - 31
PB  - Federation Amer Soc Exp Biol
PY  - 2017
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease with limited therapeutic options and unknown etiology. IPF is characterized by epithelial cell injury, impaired cellular crosstalk between epithelial cells and fibroblasts, and the formation of fibroblast foci with increased extracellular matrix deposition (ECM). We investigated the role of runt-related transcription factor 2 (RUNX2), a master regulator of bone development that has been linked to profibrotic signaling. RUNX2 expression was up-regulated in lung homogenates from patients with IPF and in experimental bleomycin-induced lung fibrosis. The RUNX2 level correlated with disease severity as measured by decreased diffusing capacity and increased levels of the IPF biomarker, matrix metalloproteinase 7. Nuclear RUNX2 was observed in prosurfactant protein C-positive hyperplastic epithelial cells and was rarely found in myofibroblasts. We discovered an up-regulation of RUNX2 in fibrotic alveolar epithelial type II (ATII) cells as well as an increase of RUNX2-negative fibroblasts in experimental and human pulmonary fibrosis. Functionally, small interfering RNA-mediated RUNX2 knockdown decreased profibrotic ATII cell function, such as proliferation and migration, whereas fibroblasts displayed activation markers and increased ECM expression after RUNX2 knockdown. This study reveals that RUNX2 is differentially expressed in ATII cells vs. fibroblasts in lung fibrosis, which contributes to profibrotic cell function. Cell-specific targeting of RUNX2 pathways may represent a therapeutic approach for IPF.
AU  - Mümmler, C.
AU  - Burgy, O.*
AU  - Hermann, S.
AU  - Mutze, K.
AU  - Günther, A.*
AU  - Königshoff, M.*
C1  - 52057
C2  - 43696
CY  - Bethesda
SP  - 703-716
TI  - Cell-specific expression of runt-related transcription factor 2 contributes to pulmonary fibrosis.
JO  - FASEB J.
VL  - 32
IS  - 2
PB  - Federation Amer Soc Exp Biol
PY  - 2017
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - TGF-β is important in lung injury and remodeling processes. TGF-β and Wingless/integrase-1 (WNT) signaling are interconnected; however, the WNT ligand-receptor complexes involved are unknown. Thus, we aimed to identify Frizzled (FZD) receptors that mediate TGF-β-induced profibrotic signaling. MRC-5 and primary human lung fibroblasts were stimulated with TGF-β1, WNT-5A, or WNT-5B in the presence and absence of specific pathway inhibitors. Specific small interfering RNA was used to knock down FZD8. In vivo studies using bleomycin-induced lung fibrosis were performed in wild-type and FZD8-deficient mice. TGF-β1 induced FZD8 specifically via Smad3-dependent signaling in MRC-5 and primary human lung fibroblasts. It is noteworthy that FZD8 knockdown reduced TGF-β1-induced collagen Iα1, fibronectin, versican, α-smooth muscle (sm)-actin, and connective tissue growth factor. Moreover, bleomycin-induced lung fibrosis was attenuated in FZD8-deficient mice in vivo. Although inhibition of canonical WNT signaling did not affect TGF-β1-induced gene expression in vitro, noncanonical WNT-5B mimicked TGF-β1-induced fibroblast activation. FZD8 knockdown reduced both WNT-5B-induced gene expression of fibronectin and α-sm-actin, as well as WNT-5B-induced changes in cellular impedance. Collectively, our findings demonstrate a role for FZD8 in TGF-β-induced profibrotic signaling and imply that WNT-5B may be the ligand for FZD8 in these responses.
AU  - Spanjer, A.I.*
AU  - Baarsma, H.A.
AU  - Oostenbrink, L.M.
AU  - Jansen, S.R.*
AU  - Kuipers, C.C.*
AU  - Lindner, M.*
AU  - Postma, D.S.*
AU  - Meurs, H.*
AU  - Heijink, I.H.*
AU  - Gosens, R.*
AU  - Königshoff, M.
C1  - 47843
C2  - 39510
CY  - Bethesda
SP  - 1823-1835
TI  - TGF-β-induced profibrotic signaling is regulated in part by the WNT receptor Frizzled-8.
JO  - FASEB J.
VL  - 30
IS  - 5
PB  - Federation Amer Soc Exp Biol
PY  - 2016
SN  - 0892-6638
ER  - 

TY  - JOUR
AU  - Dietrich, A.*
AU  - Hofmann, K.*
AU  - Königshoff, M.
AU  - Gudermann, T.*
C1  - 47140
C2  - 39229
TI  - Dissecting the role of TRPC6 channels in pulmonary fibrosis.
JO  - FASEB J.
VL  - 29
PY  - 2015
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Integrin-based mechanotransduction involves a complex focal adhesion (FA)-associated machinery that is able to detect and respond to forces exerted either through components of the extracellular matrix or the intracellular contractile actomyosin network. Here, we show a hitherto unrecognized regulatory role of vimentin intermediate filaments (IFs) in this process. By studying fibroblasts in which vimentin IFs were decoupled from FAs, either because of vimentin deficiency (V0) or loss of vimentin network anchorage due to deficiency in the cytolinker protein plectin (P0), we demonstrate attenuated activation of the major mechanosensor molecule FAK and its downstream targets Src, ERK1/2, and p38, as well as an up-regulation of the compensatory feedback loop acting on RhoA and myosin light chain. In line with these findings, we show strongly reduced FA turnover rates in P0 fibroblasts combined with impaired directional migration, formation of protrusions, and up-regulation of "stretched" high-affinity integrin complexes. By exploiting tension-independent conditions, we were able to mechanistically link these defects to diminished cytoskeletal tension in both P0 and V0 cells. Our data provide important new insights into molecular mechanisms underlying cytoskeleton-regulated mechanosensing, a feature that is fundamental for controlled cell movement and tumor progression.
AU  - Gregor, M.*
AU  - Osmanagic-Myers, S.*
AU  - Burgstaller, G.
AU  - Wolfram, M.*
AU  - Fischer, I.*
AU  - Walko, G.*
AU  - Resch, G.P.*
AU  - Jörgl, A.*
AU  - Herrmann, H.*
AU  - Wiche, G.*
C1  - 42915
C2  - 35742
SP  - 715-729
TI  - Mechanosensing through focal adhesion-anchored intermediate filaments.
JO  - FASEB J.
VL  - 28
IS  - 2
PY  - 2014
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Mitochondrial dysfunction in white adipose tissue plays a key role in the pathogenesis of type 2 diabetes. Emerging evidence specifically suggests that altered oxidative phosphorylation in adipocytes may have a relevant effect on systemic glucose homeostasis, requiring understanding of adipocyte bioenergetics. We analyzed energetic flux of an intact human adipocyte cell model by plate-based respirometry and extracellular acidification. During differentiation, we discovered that glycolytic ATP production was increasingly replaced by mitochondrial oxidative metabolism (from 20 to 60%). This observation was corroborated by simultaneous up-regulation of canonical mitochondrial gene programs, such as peroxisome proliferator-activated receptor γ coactivator α (PGC1α; 150-fold) and cytochrome c-1 (CytC; 3-fold). Mimicking diabetic phenotypes by exposure to various glucose levels (0, 5, and 25 mM) resulted in immediate adjustments of glycolytic and mitochondrial activity that aimed to maintain intracellular ATP. We conclude that ATP deficits by mitochondrial failure are compensated by glycolytic ATP production, resulting in inefficient conversion of glucose to cellular ATP. Metabolic inefficiency may enhance glucose uptake, therefore improving systemic glucose homeostasis. Notably, mature adipocytes developed a high spare respiratory capacity (increased by 6-fold) permitting rapid adaptation to metabolic changes. Spare respiratory capacity may also allow additional metabolic scope for energy dissipation, potentially offering new therapeutic targets for the treatment of metabolic disease.-Keuper, M., Jastroch, M., Yi, C.-X., Fischer-Posovszky, P., Wabitsch, M., Tschöp, M. H., Hofmann, S. M. Spare mitochondrial respiratory capacity permits human adipocytes to maintain ATP homeostasis under hypoglycemic conditions.
AU  - Keuper, M.
AU  - Jastroch, M.
AU  - Yi, C.-X.
AU  - Fischer-Posovszky, P.*
AU  - Wabitsch, M.*
AU  - Tschöp, M.H.
AU  - Hofmann, S.M.
C1  - 28171
C2  - 32984
CY  - Bethesda
SP  - 761-770
TI  - Spare mitochondrial respiratory capacity permits human adipocytes to maintain ATP homeostasis under hypoglycemic conditions.
JO  - FASEB J.
VL  - 28
IS  - 2
PB  - Federation Amer. Soc. Exp. Biol.
PY  - 2014
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Antimicrobial peptides are a promising complement to common antibiotics, development of resistance to which is a growing problem. Here we present a de novo-designed peptide, SP1-1 (RKKRLKLLKRLL-NH2), with antimicrobial activity against multiresistant Staphylococcus aureus (minimal inhibitory concentration: 6.25 μM). Elucidation of the mode of action of this peptide revealed a strong interaction with RsbW kinase (Kd: 6.01±2.73 nM), a serine kinase negatively regulating the activity of the transcription factor σB (SigB). SP1-1 binding and functional modulation of RsbW were shown in vitro by a combination of biochemical, molecular, and biophysical methods, which were further genetically evidenced in vivo by analysis of S. aureus ΔsigB deletion mutants. Intracellular localization of the peptide was demonstrated using nanometer-scaled secondary ion mass spectrometry. Moreover, microarray analysis revealed that transcription of numerous genes, involved in cell wall and amino acid metabolism, transport mechanisms, virulence, and pigmentation, is affected. Interestingly, several WalR binding motif containing genes are induced by SP1-1. In sum, the designed peptide SP1-1 seems to have multiple modes of action, including inhibition of a kinase, and therefore might contribute to the development of new antibacterial compounds, giving bacterial kinase inhibition a closer inspection.
AU  - Dangel, A.
AU  - Ackermann, N.*
AU  - Abdel-Hadi, O.*
AU  - Maier, R.*
AU  - Onder, K.*
AU  - Francois, P.*
AU  - Müller, C.W.*
AU  - Pané-Farré, J.*
AU  - Engelmann, S.*
AU  - Schrenzel, J.*
AU  - Heesemann, J.*
AU  - Lindermayr, C.
C1  - 28257
C2  - 33035
SP  - 4476-4488
TI  - A de novo-designed antimicrobial peptide with activity against multiresistant Staphylococcus aureus acting on RsbW kinase.
JO  - FASEB J.
VL  - 27
IS  - 11
PB  - Federation Amer. Soc. Exp. Biol.
PY  - 2013
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - The hepatic phosphatidylcholine (PC) transporter ATP-binding cassette (ABC) B4 flops PC from hepatocytes into bile, and its dysfunction causes chronic cholestasis and fibrosis. Because a nuclear receptor-dependent PC pathway has been determined to exert antidiabetic effects, we now analyzed the role of ABCB4 in glucose metabolism. We bred congenic Abcb4-knockout (Abcb4(-/-)) mice on the fibrosis-susceptible BALB/cJ background. Knockout mice and wild-type controls were phenotyped by measuring plasma glucose concentrations, intraperitoneal glucose tolerance, hepatic RNA expression profiles, and liver histology. In addition, 4 procholestatic ABCB4 gene variants were correlated with blood glucose levels in 682 individuals from 2 independent European cohorts. Systemic glucose levels differ significantly between Abcb4(-/-) mice and wild-type controls, and knockout mice display improved glucose tolerance with significantly lower area under the curve values on intraperitoneal glucose challenge. Of note, hepatic expression of the antidiabetic nuclear receptor 5A2 (LRH-1) is induced consistently in Abcb4(-/-) mice, and its specific rare PC ligands are detected in liver by mass spectrometry imaging. In humans, serum glucose levels are associated significantly with the common ABCB4 variant c.711A>T. In summary, ABCB4 might play a critical role in glucose homeostasis in mice and humans. We speculate that the effects could be mediated via LRH-1-dependent PC pathways.-Hochrath, K., Krawczyk, M., Goebel, R., Langhirt, M., Rathkolb, B., Micklich, K., Rozman, J., Horsch, M., Beckers, J., Klingenspor, M., Fuchs, H., Gailus-Durner, V., Wolf, E., Acalovschi, M., Volmer, D. A., Hrabě de Angelis, M., Lammert, F. The hepatic phosphatidylcholine transporter ABCB4 as modulator of glucose homeostasis.
AU  - Hochrath, K.*
AU  - Krawczyk, M.*
AU  - Goebel, R.*
AU  - Rathkolb, B.
AU  - Micklich, K.
AU  - Rozman, J.
AU  - Horsch, M.
AU  - Beckers, J.
AU  - Klingenspor, M.*
AU  - Fuchs, H.
AU  - Gailus-Durner, V.
AU  - Wolf, E.*
AU  - Acalovschi, M.*
AU  - Volmer, D. A.*
AU  - Hrabě de Angelis, M.
AU  - Lammert, F.*
C1  - 10761
C2  - 30363
SP  - 5081-5091
TI  - The hepatic phosphatidylcholine transporter ABCB4 as modulator of glucose homeostasis.
JO  - FASEB J.
VL  - 26
IS  - 12
PB  - Federation Amer. Soc. Exp. Biol.
PY  - 2012
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Cytochrome c oxidase (COX) is the terminal enzyme of the mitochondrial electron transport chain. The purpose of this study was to analyze the function of lung-specific cytochrome c oxidase subunit 4 isoform 2 (COX4i2) in vitro and in COX4i2-knockout mice in vivo. COX was isolated from cow lung and liver as control and functionally analyzed. COX4i2-knockout mice were generated and the effect of the gene knockout was determined, including COX activity, tissue energy levels, noninvasive and invasive lung function, and lung pathology. These studies were complemented by a comprehensive functional screen performed at the German Mouse Clinic (Institute of Experimental Genetics, Neuherberg, Germany). We show that isolated cow lung COX containing COX4i2 is about twice as active (88 and 102% increased activity in the presence of allosteric activator ADP and inhibitor ATP, respectively) as liver COX, which lacks COX4i2. In COX4i2-knockout mice, lung COX activity and cellular ATP levels were significantly reduced (-50 and -29%, respectively). Knockout mice showed decreased airway responsiveness (60% reduced P(enh) and 58% reduced airway resistance upon challenge with 25 and 100 mg methacholine, respectively), and they developed a lung pathology deteriorating with age that included the appearance of Charcot-Leyden crystals. In addition, there was an interesting sex-specific phenotype, in which the knockout females showed reduced lean mass (-12%), reduced total oxygen consumption rate (-8%), improved glucose tolerance, and reduced grip force (-14%) compared to wild-type females. Our data suggest that high activity lung COX is a central determinant of airway function and is required for maximal airway responsiveness and healthy lung function. Since airway constriction requires energy, we propose a model in which reduced tissue ATP levels explain protection from airway hyperresponsiveness, i.e., absence of COX4i2 leads to reduced lung COX activity and ATP levels, which results in impaired airway constriction and thus reduced airway responsiveness; long-term lung pathology develops in the knockout mice due to impairment of energy-costly lung maintenance processes; and therefore, we propose mitochondrial oxidative phosphorylation as a novel target for the treatment of respiratory diseases, such as asthma.-Hüttemann, M., Lee, I., Gao, X., Pecina, P., Pecinova, A., Liu, J., Aras, S., Sommer, N., Sanderson, T. H., Tost, M., Neff, F., Aguilar-Pimentel, J. A., Becker, L., Naton, B., Rathkolb, B., Rozman, J., Favor, J., Hans, W., Prehn, C., Puk, O., Schrewe, A., Sun, M., Höfler, H., Adamski, J., Bekeredjian, R., Graw, J., Adler, T., Busch, D. H., Klingenspor, M., Klopstock, T., Ollert, M., Wolf, E., Fuchs, H., Gailus-Durner, V., Hrabě de Angelis, M., Weissmann, N., Doan, J. W., Bassett, D. J. P., Grossman, L. I. Cytochrome c oxidase subunit 4 isoform 2-knockout mice show reduced enzyme activity, airway hyporeactivity, and lung pathology.
AU  - Hüttemann, M.*
AU  - Lee, I.*
AU  - Gao, X.*
AU  - Pecina, P.*
AU  - Pecinova, A.*
AU  - Liu, J.*
AU  - Aras, S.*
AU  - Sommer, N.*
AU  - Sanderson, T.H.*
AU  - Tost, M.
AU  - Neff, F.
AU  - Aguilar-Pimentel, J.A.
AU  - Becker, L.
AU  - Naton, B.
AU  - Rathkolb, B.
AU  - Rozman, J.
AU  - Favor, J.
AU  - Hans, W.
AU  - Prehn, C.
AU  - Puk, O.
AU  - Schrewe, A.
AU  - Sun, M.
AU  - Höfler, H.
AU  - Adamski, J.
AU  - Bekeredjian, R.*
AU  - Graw, J.
AU  - Adler, T.
AU  - Busch, D.H.*
AU  - Klingenspor, M.*
AU  - Klopstock, T.
AU  - Ollert, M.*
AU  - Wolf, E.*
AU  - Fuchs, H.
AU  - Gailus-Durner, V.
AU  - Hrabě de Angelis, M.
AU  - Weissmann, N.*
AU  - Doan, J.W.*
AU  - Bassett, D.J.*
AU  - Grossman, L.I.*
C1  - 8329
C2  - 30060
SP  - 2916-2930
TI  - Cytochrome c oxidase subunit 4 isoform 2-knockout mice show reduced enzyme activity, airway hyporeactivity, and lung pathology.
JO  - FASEB J.
VL  - 26
IS  - 9
PB  - FEDERATION AMER. SOC. EXP. BIOL.
PY  - 2012
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Metabolic challenge protocols, such as the oral glucose tolerance test, can uncover early alterations in metabolism preceding chronic diseases. Nevertheless, most metabolomics data accessible today reflect the fasting state. To analyze the dynamics of the human metabolome in response to environmental stimuli, we submitted 15 young healthy male volunteers to a highly controlled 4 d challenge protocol, including 36 h fasting, oral glucose and lipid tests, liquid test meals, physical exercise, and cold stress. Blood, urine, exhaled air, and breath condensate samples were analyzed on up to 56 time points by MS-and NMR-based methods, yielding 275 metabolic traits with a focus on lipids and amino acids. Here, we show that physiological challenges increased interindividual variation even in phenotypically similar volunteers, revealing metabotypes not observable in baseline metabolite profiles; volunteer-specific metabolite concentrations were consistently reflected in various biofluids; and readouts from a systematic model of beta-oxidation (e. g., acetylcarnitine/palmitylcarnitine ratio) showed significant and stronger associations with physiological parameters (e. g., fat mass) than absolute metabolite concentrations, indicating that systematic models may aid in understanding individual challenge responses. Due to the multitude of analytical methods, challenges and sample types, our freely available metabolomics data set provides a unique reference for future metabolomics studies and for verification of systems biology models.-Krug, S., Kastenmuller, G., Stuckler, F., Rist, M. J., Skurk, T., Sailer, M., Raffler, J., Romisch-Margl, W., Adamski, J., Prehn, C., Frank, T., Engel, K.-H., Hofmann, T., Luy, B., Zimmermann, R., Moritz, F., Schmitt-Kopplin, P., Krumsiek, J., Kremer, W., Huber, F., Oeh, U., Theis, F. J., Szymczak, W., Hauner, H., Suhre, K., Daniel, H. The dynamic range of the human metabolome revealed by challenges. FASEB J. 26, 2607-2619 (2012). www.fasebj.org
AU  - Krug, S.*
AU  - Kastenmüller, G.
AU  - Stückler, F.
AU  - Rist, M.J.*
AU  - Skurk, T.*
AU  - Sailer, M.*
AU  - Raffler, J.
AU  - Römisch-Margl, W.
AU  - Adamski, J.
AU  - Prehn, C.
AU  - Frank, T.*
AU  - Engel, K.-H.*
AU  - Hofmann, T.*
AU  - Luy, B.*
AU  - Zimmermann, R.
AU  - Moritz, F.
AU  - Schmitt-Kopplin, P.
AU  - Krumsiek, J.
AU  - Kremer, W.*
AU  - Huber, F.*
AU  - Oeh, U.
AU  - Theis, F.J.
AU  - Szymczak, W.
AU  - Hauner, H.*
AU  - Suhre, K.
AU  - Daniel, H.*
C1  - 7575
C2  - 30133
SP  - 2607-2619
TI  - The dynamic range of the human metabolome revealed by challenges.
JO  - FASEB J.
VL  - 26
IS  - 6
PB  - Federation Amer. Soc. Exp. Biol.
PY  - 2012
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Mutations in the SRGAP3 gene residing on chromosome 3p25 have previously been associated with intellectual disability. Genome-wide association studies have also revealed SRGAP3, together with genes from the same cellular network, as risk genes for schizophrenia. SRGAP3 regulates cytoskeletal dynamics through the RHO protein RAC1. RHO proteins are known to be involved in cytoskeletal reorganization during brain development to control processes such as synaptic plasticity. To elucidate the importance of SRGAP3 in brain development, we generated Srgap3-knockout mice. Ten percent of these mice developed a hydrocephalus and died before adulthood. Surviving mice showed various neuroanatomical changes, including enlarged lateral ventricles, white matter tracts, and dendritic spines together with molecular changes, including an increased basal activity of RAC1. Srgap3(-/-) mice additionally exhibited a complex behavioral phenotype. Behavioral studies revealed an impaired spontaneous alternation and social behavior, while long-term memory was unchanged. The animals also had tics. Lower locomotor activity was observed in male Srgap3(-/-) only. Srgap3(-/-) mice showed increased methylphenidate stimulation in males and an impaired prepulse inhibition in females. Together, the results show neurodevelopmental aberration in Srgap3(-/-) mice, with many of the observed phenotypes matching several schizophrenia-related intermediate phenotypes. Mutations of SRGAP3 may thus contribute to various neurodevelopmental disorders.
AU  - Waltereit, R.*
AU  - Leimer, U.*
AU  - von Bohlen und Halbach, O.*
AU  - Panke, J.*
AU  - Hölter, S.M.
AU  - Garrett, L.
AU  - Wittig, K.*
AU  - Schneider, M.*
AU  - Schmitt, C.*
AU  - Calzada-Wack, J.
AU  - Neff, F.
AU  - Becker, L.
AU  - Prehn, C.
AU  - Kutscherjawy, S.*
AU  - Endris, V.*
AU  - Bacon, C.*
AU  - Fuchs, H.
AU  - Gailus-Durner, V.
AU  - Berger, S.*
AU  - Schönig, K.*
AU  - Adamski, J.
AU  - Klopstock, T.*
AU  - Esposito, I.
AU  - Wurst, W.
AU  - Hrabě de Angelis, M.
AU  - Rappold, G.*
AU  - Wieland, T.*
AU  - Bartsch, D.*
C1  - 8248
C2  - 29989
SP  - 4418-4428
TI  - Srgap3-/- mice present a neurodevelopmental disorder with schizophrenia-related intermediate phenotypes.
JO  - FASEB J.
VL  - 26
IS  - 11
PB  - Federation Amer. Soc. Exp. Biol.
PY  - 2012
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Transcriptional regulation by hormonal 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] involves occupancy of vitamin D response elements (VDREs) by the VDRE binding protein (VDRE-BP) or 1,25(OH)(2)D(3)-bound vitamin D receptor (VDR). This relationship is disrupted by elevated VDRE-BP, causing a form of hereditary vitamin D-resistant rickets (HVDRR). DNA array analysis showed that of 114 genes regulated by 1,25(OH)(2)D(3) in control cells, almost all (113) were rendered insensitive to the hormone in VDRE-BP-overexpressing HVDRR cells. Among these was the gene for DNA-damage-inducible transcript 4 (DDIT4), an inhibitor of mammalian target of rapamycin (mTOR) signaling. Chromatin immunoprecipitation PCR using 1,25(OH)(2)D(3)-treated osteoblasts confirmed that VDR and VDRE-BP compete for binding to the DDIT4 gene promoter. Expression of DDIT4 mRNA in these cells was induced (1.6-6 fold) by 1,25(OH)(2)D(3) (10-100 nM), and Western blot and flow cytometry analysis showed that this response involved suppression of phosphorylated S6K1(T389) (a downstream target of mTOR) similar to rapamycin treatment. siRNA knockdown of DDIT4 completely abrogated antiproliferative responses to 1,25(OH)(2)D(3), whereas overexpression of VDRE-BP exerted a dominant-negative effect on transcription of 1,25(OH)(2)D(3)-target genes. DDIT4, an inhibitor of mTOR signaling, is a direct target for 1,25(OH)(2)D(3) and VDRE-BP, and functions to suppress cell proliferation in response to vitamin D.
AU  - Lisse, T.S.*
AU  - Liu, T.*
AU  - Irmler, M.
AU  - Beckers, J.
AU  - Chen, H.*
AU  - Adams, J.S.*
AU  - Hewison, M.*
C1  - 6110
C2  - 28436
CY  - Bethesda, USA
SP  - 937-947
TI  - Gene targeting by the vitamin D response element binding protein reveals a role for vitamin D in osteoblast mTOR signaling.
JO  - FASEB J.
VL  - 25
IS  - 3
PB  - Federation Amer. Soc. Exp. Biol.
PY  - 2011
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Selenoproteins are expressed in many organisms, including bacteria, insects, fish, and mammals. Yet, it has remained obscure why some organisms rely on selenoproteins while others, like yeast and plants, express Cys-containing homologues. This study addressed the possible advantage of selenocysteine (Sec) vs. Cys in the essential selenoprotein glutathione peroxidase 4 (GPx4), using 4-hydroxy-tamoxifen-inducible Cre-excision of loxP-flanked GPx4 alleles in murine cells. Previously, it was shown that GPx4 disruption caused rapid cell death, which was prevented by α-tocopherol. Results presented herein demonstrate that the expression of wild-type (WT) GPx4 and its Sec/Cys (U46C) mutant rescued cell death of GPx4(-/-) cells, whereas the Sec/Ser (U46S) mutant failed. Notably, the specific activity of U46C was decreased by ∼90% and was indistinguishable from U46S-expressing and mock-transfected cells. Hence, the U46C mutant prevented apoptosis despite hardly measurable in vitro activity. Doxycycline-inducible expression revealed that minute amounts of either U46C or WT GPx4 prevented cell death, albeit WT GPx4 was more efficient. Interestingly, at the same expression level, proliferation was promoted in U46C-expressing cells but attenuated in WT-expressing cells. In summary, both catalytic efficiency and the expression level of GPx4 control the balance between cell survival and proliferation.-Mannes, A. M., Seiler, A., Bosello, V., Maiorino, M., Conrad, M. Cysteine mutant of mammalian GPx4 rescues cell death induced by disruption of the wild-type selenoenzyme.
AU  - Mannes, A.M.
AU  - Seiler, A.
AU  - Bosello, V.*
AU  - Maiorino, M.*
AU  - Conrad, M.
C1  - 815
C2  - 28409
SP  - 2135-2144
TI  - Cysteine mutant of mammalian GPx4 rescues cell death induced by disruption of the wild type selenoenzyme.
JO  - FASEB J.
VL  - 25
IS  - 7
PB  - FASEB
PY  - 2011
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Malfunctioning of system x(c)(-), responsible for exchanging intracellular glutamate for extracellular cystine, can cause oxidative stress and excitotoxicity, both important phenomena in the pathogenesis of Parkinson's disease (PD). We used mice lacking xCT (xCT(-/-) mice), the specific subunit of system x(c)(-), to investigate the involvement of this antiporter in PD. Although cystine that is imported via system x(c)(-) is reduced to cysteine, the rate-limiting substrate in the synthesis of glutathione, deletion of xCT did not result in decreased glutathione levels in striatum. Accordingly, no signs of increased oxidative stress could be observed in striatum or substantia nigra of xCT(-/-) mice. In sharp contrast to expectations, xCT(-/-) mice were less susceptible to 6-hydroxydopamine (6-OHDA)-induced neurodegeneration in the substantia nigra pars compacta compared to their age-matched wild-type littermates. This reduced sensitivity to a PD-inducing toxin might be related to the decrease of 70% in striatal extracellular glutamate levels that was observed in mice lacking xCT. The current data point toward system x(c)(-) as a possible target for the development of new pharmacotherapies for the treatment of PD and emphasize the need to continue the search for specific ligands for system x(c)(-).-Massie, A., Schallier, A., Kim, S. W., Fernando, R., Kobayashi, S., Beck, H., De Bundel, D., Vermoesen, K., Bannai, S., Smolders, I., Conrad, M., Plesnila, N., Sato, H., Michotte, Y. Dopaminergic neurons of system x(c)(-)-deficient mice are highly protected against 6-hydroxydopamine-induced toxicity.
AU  - Massie, A.*
AU  - Schallier, A.*
AU  - Kim, S.W.*
AU  - Fernando, R.*
AU  - Kobayashi, S.*
AU  - Beck, H.*
AU  - de Bundel, D.*
AU  - Vermoesen, K.*
AU  - Bannai, S.*
AU  - Smolders, I.*
AU  - Conrad, M.
AU  - Plesnila, N.*
AU  - Sato, H.*
AU  - Michotte, Y.*
C1  - 5503
C2  - 28147
SP  - 1359-1369
TI  - Dopaminergic neurons of system xc‾-deficient mice are highly protected against 6-hydroxydopamine-induced toxicity.
JO  - FASEB J.
VL  - 25
IS  - 4
PB  - FASEB
PY  - 2011
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Idiopathic pulmonary fibrosis (IPF) is characterized by exaggerated fibroblast proliferation and accumulation of collagens and fibronectin. The extracellular fibronectin and collagen network is regulated by von Hippel-Lindau protein (pVHL). However, it is unknown whether pVHL contributes to pulmonary fibrosis. We found that lungs from patients with IPF expressed increased levels of pVHL in fibroblastic foci. Bleomycin treatment also induced pVHL in lung fibroblasts, but not in alveolar type II cells. Overexpression of pVHL increased lung fibroblast proliferation, protein abundance of fibronectin and collagen, and extracellular fibronectin. In addition, overexpression of pVHL induced expression of the α5 integrin subunit. Overexpression of pVHL did not alter hypoxia-inducible factor luciferase reporter activity and mRNA expression of vascular endothelial growth factor. Fibroblasts overexpressing pVHL were more sensitive to RGD peptide-mediated reduction in proliferation. Activating α5 and β1 integrin increased proliferation of fibroblasts overexpressing pVHL and those cells were more resistant to the inhibition of α5 integrin. Overexpression of pVHL also increased activation of focal adhesion kinase (FAK). Moreover, suppression of pVHL prevented TGF-β1-induced proliferation of mouse embryonic fibroblasts. Taken together, our results indicate that elevated expression of pVHL results in the aberrant fibronectin expression, activation of integrin/FAK signaling, fibroblast proliferation, and fibrosis.-Zhou, Q., Pardo, A., Königshoff, M., Eickelberg, O., Budinger, G. R. S., Thavarajah, K., Gottardi, C. J., Jones, J., Varga, J., Selman, M., Sznajder, J. I., Raj, J. U., Zhou, G. Role of von Hippel-Lindau protein in fibroblast proliferation and fibrosis.
AU  - Zhou, Q.*
AU  - Pardo, A.*
AU  - Königshoff, M.
AU  - Eickelberg, O.
AU  - Budinger, G.R.*
AU  - Thavarajah, K.*
AU  - Gottardi, C.J.*
AU  - Jones, J.*
AU  - Varga, J.*
AU  - Selman, M.*
AU  - Sznajder, J.I.*
AU  - Raj, J.U.*
AU  - Zhou, G.
C1  - 4433
C2  - 28577
SP  - 3032-3044
TI  - Role of von Hippel-Lindau protein in fibroblast proliferation and fibrosis.
JO  - FASEB J.
VL  - 25
IS  - 9
PB  - FASEB
PY  - 2011
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Megakaryocytes, which mature from hematopoietic progenitors in the bone marrow, further differentiate by reorganizing their cytoplasm into long proplatelet extensions that release platelets into the circulation. The molecular mechanisms underlying this highly dynamic cytoplasmic and cytoskeletal remodeling process are only poorly understood. Here we report that sphingosine 1-phosphate receptor 4 (S1P(4)) is specifically up-regulated during the development of human megakaryocytes from progenitor cells and is expressed in mature murine megakaryocytes. Megakaryocytes generated from S1P(4)-deficient murine bone marrow showed atypical and reduced formation of proplatelets in vitro. The recovery of platelet numbers after experimental thrombocytopenia was significantly delayed in S1p4(-/-) mice. Remarkably, overexpression and stimulation of S1P(4) in human erythroleukemia HEL cells promoted endomitosis, formation of cytoplasmic extensions, and subsequent release of platelet-like particles. These observations indicate that S1P(4) is involved in shaping the terminal differentiation of megakaryocytes.-Golfier, S., Kondo, S., Schulze, T., Takeuchi, T., Vassileva, G., Achtman, A. H., Gräler, M. H., Abbondanzo, S. J., Wiekowski, M., Kremmer, E., Endo, Y., Lira, S. A., Bacon, K. B., Lipp, M. Shaping of terminal megakaryocyte differentiation and proplatelet development by sphingosine-1-phosphate receptor S1P(4).
AU  - Golfier, S.*
AU  - Kondo, S.*
AU  - Schulze, T.*
AU  - Takeuchi, T.*
AU  - Vassileva, G.*
AU  - Achtman, A.H.*
AU  - Gräler, M.H.*
AU  - Abbondanzo, S.J.*
AU  - Wiekowski, M.*
AU  - Kremmer, E.
AU  - Endo, Y.*
AU  - Lira, S.A.*
AU  - Bacon, K.B.*
AU  - Lipp, M.*
C1  - 5665
C2  - 27964
SP  - 4701-4710
TI  - Shaping of terminal megakaryocyte differentiation and proplatelet development by sphingosine-1-phosphate receptor S1P4.
JO  - FASEB J.
VL  - 24
IS  - 12
PB  - FASEB
PY  - 2010
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Cerebral selenium (Se) deficiency is associated with neurological phenotypes including seizures and ataxia. We wanted to define whether neurons require selenoprotein expression and which selenoproteins are most important, and explore the possible pathomechanism. Therefore, we abrogated the expression of all selenoproteins in neurons by genetic inactivation of the tRNA[Ser](Sec) gene. Cerebral expression of selenoproteins was significantly diminished in the mutants, and histological analysis revealed progressive neurodegeneration. Developing interneurons failed to specifically express parvalbumin (PV) in the mutants. Electrophysiological recordings, before overt cell death, showed normal excitatory transmission, but revealed spontaneous epileptiform activity consistent with seizures in the mutants. In developing cortical neuron cultures, the number of PV(+) neurons was reduced on combined Se and vitamin E deprivation, while other markers, such as calretinin (CR) and GAD67, remained unaffected. Because of the synergism between Se and vitamin E, we analyzed mice lacking neuronal expression of the Se-dependent enzyme glutathione peroxidase 4 (GPx4). Although the number of CR(+) interneurons remained normal in Gpx4-mutant mice, the number of PV(+) interneurons was reduced. Since these mice similarly exhibit seizures and ataxia, we conclude that GPx4 is a selenoenzyme modulating interneuron function and PV expression. Cerebral SE deficiency may thus act via reduced GPx4 expression.-Wirth, E. K., Conrad, M., Winterer, J., Wozny, C., Carlson, B. A., Roth, S., Schmitz, D., Bornkamm, G. W., Coppola, V., Tessarollo, L., Schomburg, L., Köhrle, J., Hatfield, D. L., Schweizer, U. Neuronal selenoprotein expression is required for interneuron development and prevents seizures and neurodegeneration.
AU  - Wirth, E.K.*
AU  - Conrad, M.
AU  - Winterer, J.*
AU  - Wozny, C.*
AU  - Carlson, B.A.*
AU  - Roth, S.*
AU  - Schmitz, D.*
AU  - Bornkamm, G.W.
AU  - Coppola, V.*
AU  - Tessarollo, L.*
AU  - Schomburg, L.*
AU  - Köhrle, J.*
AU  - Hatfield, D.L.*
AU  - Schweizer, U.*
C1  - 5827
C2  - 27976
SP  - 844-852
TI  - Neuronal selenoprotein expression is required for interneuron development and prevents seizures and neurodegeneration.
JO  - FASEB J.
VL  - 24
IS  - 3
PB  - FASEB
PY  - 2010
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Hypoxia is well known to limit curability of tumors by ionizing radiation. Here, we show that hypoxia treatment of tumor cells causes coexpression of heat shock protein 70 (Hsp70) and phosphatidylserine (PS) on the cell surface. Colocalization of Hsp70 and PS, as determined by confocal microscopy, also occurs when exogenous FITC-labeled Hsp70 protein is added to normoxic and hypoxic tumor cells. Moreover, the interaction of Hsp70 with PS was demonstrated in artificial unilamellar phosphatidylcholine/ phosphatidylserine (PC/PS) liposomes at the physiological ratio of 8/2. Indeed, the Hsp70-liposome interaction gradually increased with elevating PS molar ratios (8/2 > or = 7/3 < 5/5 < 4/6 < 3/7 < 2/8). In contrast, only a weak Hsp70 interaction was detected in phosphatidylcholine/phosphatidylglycerol (PC/PG) liposomes, thus demonstrating that the interaction was not a charge-related effect. The interaction of Hsp70 with surface PS significantly reduces clonogenic cell survival in normoxic (EC(50) of Hsp70=85 microg/ml) and hypoxic (EC(50) of Hsp70=55 microg/ml) tumor cells. The radiation-induced tumor cell killing was significantly enhanced by the addition of Hsp70 protein (50 microg/ml). Since apoptosis was not significantly enhanced in normoxic and hypoxic tumor cells by the addition of Hsp70, we hypothesize that the Hsp70 protein-induced reduction in clonogenic cell survival might be through necrosis rather than apoptosis.
AU  - Schilling, D.
AU  - Gehrmann, M.
AU  - Steinem, C.*
AU  - de Maio, A.*
AU  - Pockley, A.G.*
AU  - Abend, M.*
AU  - Molls, M.
AU  - Multhoff, G.
C1  - 288
C2  - 26275
SP  - 2467-2477
TI  - Binding of heat shock protein 70 to extracellular phosphatidylserine promotes killing of normoxic and hypoxic tumor cells.
JO  - FASEB J.
VL  - 23
IS  - 8
PB  - Federation Amer Soc Exp Biol
PY  - 2009
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Selenium is linked to male fertility. Glutathione peroxidase 4 (GPx4), first described as an antioxidant enzyme, is the predominant selenoenzyme in testis and has been suspected of being vital for spermatogenesis. Cytosolic, mitochondrial, and nuclear isoforms are all encoded by the same gene. While disruption of entire GPx4 causes early embryonic lethality in mice, inactivation of nuclear GPx4 does not impair embryonic development or fertility. Here, we show that deletion of mitochondrial GPx4 (mGPx4) allows both normal embryogenesis and postnatal development, but causes male infertility. Infertility was associated with impaired sperm quality and severe structural abnormalities in the midpiece of spermatozoa. Knockout sperm display higher protein thiol content and recapitulate features typical of severe selenodeficiency. Interestingly, male infertility induced by mGPx4 depletion could be bypassed by intracytoplasmic sperm injection. We also show for the first time that mGPx4 is the prevailing GPx4 product in male germ cells and that mGPx4 disruption has no effect on proliferation or apoptosis of germinal or somatic tissue. Our study finally establishes that mitochondrial GPx4 confers the vital role of selenium in mammalian male fertility and identifies cytosolic GPx4 as the only GPx4 isoform being essential for embryonic development and apoptosis regulation.
AU  - Schneider, M.
AU  - Förster, H.
AU  - Boersma, A.
AU  - Seiler, A.
AU  - Wehnes, H.
AU  - Sinowatz, F.*
AU  - Neumüller, C.*
AU  - Deutsch, M.J.
AU  - Walch, A.K.
AU  - Hrabě de Angelis, M.
AU  - Wurst, W.
AU  - Ursini, F.*
AU  - Roveri, A.*
AU  - Maleszewski, M.*
AU  - Maiorino, M.*
AU  - Conrad, M.
C1  - 692
C2  - 26320
SP  - 3233-3242
TI  - Mitochondrial glutathione peroxidase 4 disruption causes male infertility.
JO  - FASEB J.
VL  - 23
IS  - 9
PB  - FASEB
PY  - 2009
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - The Parkinson's disease (PD)-associated gene DJ-1 mediates direct neuroprotection. The up-regulation of DJ-1 in reactive astrocytes also suggests a role in glia. Here we show that DJ-1 regulates proinflammatory responses in mouse astrocyte-rich primary cultures. When treated with a Toll-like receptor 4 agonist, the bacterial endotoxin lipopolysaccharide (LPS), Dj-1-knockout astrocytes generated >10 times more nitric oxide (NO) than littermate controls. Lentiviral reintroduction of DJ-1 restored the NO response to LPS. The enhanced NO production in Dj-1(-/-) astrocytes was mediated by a signaling pathway involving reactive oxygen species leading to specific hyperinduction of type II NO synthase [inducible NO synthase ( iNOS)]. These effects coincided with significantly increased phosphorylation of p38 mitogen-activated protein kinase (MAPK), and p38(MAPK) inhibition suppressed NO production and iNOS mRNA and protein induction. Dj-1(-/-) astrocytes also induced the proinflammatory mediators cyclooxygenase-2 and interleukin-6 significantly more strongly, but not nerve growth factor. Finally, primary neuron cultures grown on Dj-1(-/-) astrocytes became apoptotic in response to LPS in an iNOS-dependent manner, directly demonstrating the neurotoxic potential of astrocytic DJ-1 deficiency. These findings identify DJ-1 as a regulator of proinflammatory responses and suggest that loss of DJ-1 contributes to PD pathogenesis by deregulation of astrocytic neuroinflammatory damage.-Waak, J., Weber, S. S., Waldenmaier, A., Gorner, K., Alunni-Fabbroni, M., Schell, H., Vogt-Weisenhorn, D., Pham, T.-T., Reumers, V., Baekelandt, V., Wurst, W., Kahle, P. J. Regulation of astrocyte inflammatory responses by the Parkinson's disease-associated gene DJ-1.
AU  - Waak, J.*
AU  - Weber, S.S.*
AU  - Waldenmaier, A.*
AU  - Görner, K.*
AU  - Alunni-Fabbroni, M.*
AU  - Schell, H.*
AU  - Vogt Weisenhorn, D.M.
AU  - Pham, T.T.
AU  - Reumers, V.*
AU  - Baekelandt, V.*
AU  - Wurst, W.
AU  - Kahle, P.J.*
C1  - 516
C2  - 26293
SP  - 1244-1248   
TI  - Regulation of astrocyte inflammatory responses by the Parkinson's disease-associated gene DJ-1.
JO  - FASEB J.
VL  - 23
IS  - 8
PB  - Federation Amer Soc Exp Biol
PY  - 2009
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - With HIV persisting lifelong in infected persons, therapeutic vaccination is a novel alternative concept to control virus replication. Even though CD8 and CD4 cell responses to such immunizations have been demonstrated, their effects on virus replication are still unclear. In view of this fact, we studied the impact of a therapeutic vaccination with HIV nef delivered by a recombinant modified vaccinia Ankara vector on viral diversity. We investigated HIV sequences derived from chronically infected persons before and after therapeutic vaccination. Before immunization the mean +/- se pairwise variability of patient-derived Nef protein sequences was 0.1527 +/- 0.0041. After vaccination the respective value was 0.1249 +/- 0.0042, resulting in a significant (P<0.0001) difference between the two time points. The genes vif and 5'gag tested in parallel and nef sequences in control persons yielded a constant amino acid sequence variation. The data presented suggest that Nef immunization induced a selective pressure, limiting HIV sequence variability. To our knowledge this is the first report directly linking therapeutic HIV vaccination to decreasing diversity in patient-derived virus isolates.
AU  - Hoffmann, D.*
AU  - Seebach, J.*
AU  - Cosma, A.
AU  - Goebel, F.D.*
AU  - Strimmer, K.*
AU  - Schatzl, H.M.*
AU  - Erfle, V.
C1  - 3267
C2  - 25117
SP  - 437-444
TI  - Therapeutic vaccination reduces HIV sequence variability.
JO  - FASEB J.
VL  - 22
IS  - 2
PB  - FASEB
PY  - 2008
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - In mammalian prion diseases, an abnormally folded, aggregated form of the prion protein (PrP(Sc)) appears to catalyze a conformational switch of its cellular isoform (PrP(C)) to an aggregated state. A similar prion-like phenomenon has been reported for the Saccharomyces cerevisiae translation termination factor Sup35p that can adopt a self-propagating conformation. We have compared aggregation propensities of chimeric proteins derived from the Sup35p prion domain NM and PrP in vitro and in the cytosol of mammalian cells. Sup35p-NM and PrP displayed strikingly different aggregation behaviors when expressed in mammalian cells, with NM remaining soluble and cytosolic PrP spontaneously aggregating due to the globular domain of PrP. When fused to PrP(90-230), Sup35p-M exhibited an inhibitory effect for nucleation but increased aggregate growth, potentially by facilitating recruitment of newly synthesized chimeric proteins into the growing aggregates. This effect, however, could, to some extent, be counteracted by the prion-forming region Sup35p-N, thereby increasing aggregate frequency. Interestingly, a lowered nucleation rate was also observed in the presence of the amino-terminal region of PrP, suggesting that Sup35p-M and PrP(23-90) share some biological function in prion protein assembly. Our results provide new insights into prion protein aggregation behaviors, demonstrating the impact of dynamic interactions between prion domains and suggesting that aggregation of yeast and mammalian prion proteins is strongly influenced by yet unidentified cellular conditions or factors.
AU  - Krammer, C.*
AU  - Suhre, M.H.*
AU  - Kremmer, E.
AU  - Diemer, C.*
AU  - Hess, S.*
AU  - Schatzl, H.M.*
AU  - Scheibel, T.*
AU  - Vorberg, I.*
C1  - 1434
C2  - 25695
SP  - 762-773
TI  - Prion protein/protein interactions: Fusion with yeast Sup35p-NM modulates cytosolic PrP aggregation in mammalian cells.
JO  - FASEB J.
VL  - 22
IS  - 3
PB  - FASEB
PY  - 2008
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Glucocorticoids are well-established anti-inflammatory drugs thought to mainly act by inhibition of proinflammatory transcription factors like NF-{kappa}B. In recent years, however, transcription factor-independent mechanisms of glucocorticoid action have been proposed, namely the influence on MAPK pathways. Here we identify MAPK phosphatase-1 (MKP-1) as a pivotal mediator of the anti-inflammatory action of glucocorticoids in the human endothelium. We applied dexamethasone (Dex) to TNF-{alpha}-activated human endothelial cells and used the adhesion molecule E-selectin as inflammatory read-out parameter. Dex is known to reduce the expression of E-selectin, which is largely regulated by NF-{kappa}B. Here, we communicate that Dex at low concentrations (1–100 nM) markedly attenuates E-selectin expression without affecting NF-{kappa}B. Importantly, Dex is able to increase the expression of MKP-1, which causes an inactivation of TNF-{alpha}-induced p38 MAPK and mediates inhibition of E-selectin expression. In endothelial MKP-1–/– cells differentiated from MKP-1–/– embryonic stem cells and in MKP-1-silenced human endothelial cells, Dex did not inhibit TNF-{alpha}-evoked E-selectin expression. Thus, our findings introduce MKP-1 as a novel and crucial mediator of the anti-inflammatory action of glucocorticoids at low concentrations in the human endothelium and highlight MKP-1 as an important and promising anti-inflammatory drug target.—Fürst, R., Schroeder, T., Eilken, H. M., Bubik, M. F., Kiemer, A. K., Stefan Zahler, S., Vollmar, A. M. MAPK phosphatase-1 represents a novel anti-inflammatory target of glucocorticoids in the human endothelium
AU  - Fürst, R.*
AU  - Schroeder, T.
AU  - Eilken, H.M.
AU  - Bubik, M.F.*
AU  - Kiemer, A.K.*
AU  - Zahler, S.*
AU  - Vollmar, A.M.*
C1  - 2367
C2  - 24348
SP  - 74-80
TI  - MAPK phosphatase-1 represents a novel anti-inflammatory target of glucocorticoids in the human endothelium.
JO  - FASEB J.
VL  - 21
IS  - 1
PB  - FASEB
PY  - 2007
SN  - 0892-6638
ER  - 

TY  - JOUR
AU  - Rauter, I.*
AU  - Krauth, M.T.*
AU  - Flicker, S.*
AU  - Gieras, A.*
AU  - Westritschnig, K.*
AU  - Vrtala, S.*
AU  - Balic, N.*
AU  - Spitzauer, S.*
AU  - Huss-Marp, J.
AU  - Brockow, K.
AU  - Darsow, U.
AU  - Ring, J.
AU  - Behrendt, H.
AU  - Semper, H.*
AU  - Valent, P.*
AU  - Valenta, R.*
C1  - 4083
C2  - 24232
SP  - 967-969
TI  - Allergen cleavage by effector cell-derived proteases regulates allergic inflammation.
JO  - FASEB J.
VL  - 20
PY  - 2006
SN  - 0892-6638
ER  - 

TY  - JOUR
AB  - Clonal embryonic endothelial progenitor cells (eEPCs) isolated from embryonic day 7.5 mice home specifically to hypoxic areas in mouse tumor metastases but spare normal organs and do not form carcinomas. Based on these results, we assessed the potential of eEPCs to enhance vascularization and limit organ dysfunction after ischemia in syngenic and xenotypic organisms. The angiogenic potential of eEPCs was evaluated in chronic ischemic rabbit hindlimbs after regional application by retroinfusion. eEPC treatment improved limb perfusion, paralleled by an increase in capillary density and collateral blood vessel number. Systemic eEPC infusion into mice after ischemic cardiac insult increased postischemic heart output measured by a marked improvement in left ventricle developed pressure and both systolic and diastolic functions. In vitro, eEPCs strongly induced vascular outgrowths from aortic rings. To address the molecular basis of this intrinsic angiogenic potential, we investigated the eEPC transcriptome. Genome-wide Affymetrix GeneChip analysis revealed that the eEPCs express a wealth of secreted factors known to induce angiogenesis, tissue remodeling, and organogenesis that may contribute to the eEPC-mediated beneficial effects. Our findings show that eEPCs induce blood vessel growth and cardioprotection in severe ischemic conditions providing a readily available source to study the mechanisms of neovascularization and tissue recovery.
AU  - Kupatt, Ch.*
AU  - Horstkotte, J.*
AU  - Vlastos, G.A.
AU  - Posser, A.*
AU  - Lebherz, C.*
AU  - Semisch, M.
AU  - Thalgott, M.*
AU  - Büttner, K.*
AU  - Browarzyk, Ch.*
AU  - Mages, J.*
AU  - Hoffmann, R.*
C1  - 4850
C2  - 23172
SP  - 1576-1578
TI  - Embryonic endothelial progenitor cells expressing a broad range of proangiogenic and remodeling factors enhance vascularization and tissue recovery in acute and chronic ischemia.
JO  - FASEB J.
VL  - 19
IS  - 11
PY  - 2005
SN  - 0892-6638
ER  - 

TY  - JOUR
AU  - Massberg, S.*
AU  - Konrad, I.*
AU  - Bültmann, A.*
AU  - Schulz, C.*
AU  - Münch, G.*
AU  - Peluso, M.*
AU  - Lorenz, M.*
AU  - Schneider, S.*
AU  - Besta, F.*
AU  - Müller, I.*
AU  - Hu, B.*
AU  - Langer, H.*
AU  - Kremmer, E.
C1  - 9439
C2  - 22107
SP  - 397-399
TI  - Soluble glycoprotein VI dimer inhibits platelet adhesion and aggregation to the injured vessel wall in vivo.
JO  - FASEB J.
VL  - 18
PY  - 2003
SN  - 0892-6638
ER  - 

TY  - JOUR
AU  - Werner, T.
AU  - Fessele, S.*
AU  - Maier, H.
AU  - Nelson, P.J.*
C1  - 9438
C2  - 21697
SP  - 1228-1237
TI  - Computer modeling of promoter organization as a tool to study transcriptional coregulation.
JO  - FASEB J.
VL  - 17
PY  - 2003
SN  - 0892-6638
ER  - 

TY  - JOUR
AU  - Fessele, S.*
AU  - Boehlk, S.*
AU  - Mojaat, A.*
AU  - Miyamoto, N.G.*
AU  - Werner, T.
AU  - Nelson, E.L.*
AU  - Schlöndorff, D.*
AU  - Nelson, P.J.*
C1  - 1546
C2  - 22801
SP  - 577-579
TI  - Molecular and in silicio characterization of a promoter module and C/EBP element that mediate LPS-induced RANTES/CCL5 expression in monocytic cells.
JO  - FASEB J.
VL  - 15
PY  - 2001
SN  - 0892-6638
ER  - 

TY  - JOUR
AU  - Pfeifer, H.*
AU  - Conrad, M.
AU  - Roethlein, D.*
AU  - Kyriakopoulos, A.*
AU  - Brielmeier, M.
AU  - Bornkamm, G.W.
AU  - Behne, D.*
C1  - 9437
C2  - 22865
SP  - 1236-1238
TI  - Identification of a specific sperm nuclei selenoenzyme necessary for protamine thiol cross-linking during sperm maturation.
JO  - FASEB J.
VL  - 15
PY  - 2001
SN  - 0892-6638
ER  - 

TY  - JOUR
AU  - Dendorfer, A.
AU  - Schultz-Hector, S.
AU  - Nees, S.
C1  - 19660
C2  - 12785
TI  - Isolation of Pure Myocardial Capillaries (C) and Discrimination of the Constituent Endothelial Cells (EC) and Pericytes (P) in Tissue Culture.
JO  - FASEB J.
VL  - 5 (6)
PY  - 1991
SN  - 0892-6638
ER  - 

TY  - JOUR
AU  - Storck, M.
AU  - Faist, E.
AU  - Hültner, L.
AU  - Redl, H.
AU  - Walz, A.
AU  - Ertel, W.
AU  - Schildberg, F.-W.
C1  - 18397
C2  - 11599
TI  - Activation of Monocytes in Sepsis: Release of Monokines and Neopterin.
JO  - FASEB J.
PY  - 1990
SN  - 0892-6638
ER  -