TY  - JOUR
AB  - Manganese (Mn) is essential for living organisms, playing an important role in nervous system function. Nevertheless, chronic and/or acute exposure to this metal, especially during early life stages, can lead to neurotoxicity and dementia by unclear mechanisms. Thus, based on previous works of our group with yeast and zebrafish, we hypothesized that the mechanisms mediating manganese-induced neurotoxicity can be associated with the alteration of protein metabolism. These mechanisms may also depend on the chemical speciation of manganese. Therefore, the current study aimed at investigating the mechanisms mediating the toxic effects of manganese in primary cultures of cerebellar granule neurons (CGNs). By exposing cultured CGNs to different chemical species of manganese ([[2-[(dithiocarboxy)amino]ethyl]carbamodithioato]](2-)-kS,kS′]manganese, named maneb (MB), and [[1,2-ethanediylbis[carbamodithioato]](2-)]manganese mixture with [[1,2-ethanediylbis[carbamodithioato]](2-)]zinc, named mancozeb (MZ), and manganese chloride (MnCl2)), and using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, we observed that both MB and MZ induced similar cytotoxicity (LC50 ∼ 7-9 μM), which was higher than that of MnCl2 (LC50 ∼ 27 μM). Subsequently, we applied systems biology approaches, including metallomics, proteomics, gene expression and bioinformatics, and revealed that independent of chemical speciation, for non-cytotoxic concentrations (0.3-3 μM), Mn-induced neurotoxicity in CGNs is associated with metal dyshomeostasis and impaired protein metabolism. In this way, we verified that MB induced more post-translational alterations than MnCl2, which can be a plausible explanation for cytotoxic differences between both chemical species. The metabolism of proteins is one of the most energy consuming cellular processes and its impairment appears to be a key event of some cellular stress processes reported separately in other studies such as cell cycle arrest, energy impairment, cell signaling, excitotoxicity, immune response, potential protein accumulation and apoptosis. Interestingly, we verified that Mn-induced neurotoxicity shares pathways associated with the development of Alzheimer's disease, Amyotrophic Lateral Sclerosis, Huntington's disease, and Parkinson's disease. This has been observed in baker's yeast and zebrafish suggesting that the mode of action of Mn may be evolutionarily conserved.
AU  - Hernández, R.B.*
AU  - Carrascal, M.*
AU  - Abian, J.*
AU  - Michalke, B.
AU  - Farina, M.*
AU  - Gonzalez, Y.R.*
AU  - Iyirhiaro, G.O.*
AU  - Moteshareie, H.*
AU  - Burnside, D.*
AU  - Golshani, A.*
AU  - Suñol, C.*
C1  - 60622
C2  - 49421
CY  - Thomas Graham House, Science Park, Milton Rd, Cambridge Cb4 0wf, Cambs, England
SP  - 1656-1678
TI  - Manganese-induced neurotoxicity in cerebellar granule neurons due to perturbation of cell network pathways with potential implications for neurodegenerative disorders.
JO  - Metallomics
VL  - 12
IS  - 11
PB  - Royal Soc Chemistry
PY  - 2020
SN  - 1756-5901
ER  - 

TY  - JOUR
AB  - Copper is an essential element for biological functions within humans and animals. There are several known diseases associated with Cu deficiency or overload, such as Menkes disease and Wilson disease, respectively. A common clinical method for determining extractable Cu levels in serum, which is thought to be potentially dangerous if in excess, is to subtract the value of tightly incorporated Cu in ceruloplasmin from total serum Cu. In this work, an automated sample preparation and liquid chromatography (LC) system was combined with inductively coupled plasma-mass spectrometry (ICP-MS) to determine bound Cu and extractable Cu in serum. This LC-ICP-MS method took 250 s for sample preparation and analysis, followed by a column recondition/system reset, thus, a 6 minute sample-to-sample time including sample preparation. The method was validated using serum collected from either control (Atp7b(+/-)) or Wilson disease rats (Atp7b(-/-)). The extractable Cu was found to be 4.0 +/- 2.3 mu M Cu in healthy control rats, but 2.1 +/- 0.6 mu M Cu in healthy Wilson rats, and 27 +/- 16 mu M Cu in diseased Wilson rats, respectively. In addition, the extractable Cu/bound Cu ratio was found to be 6.4 +/- 3.5%, 38 +/- 29%, and 34 +/- 22%, respectively. These results suggest that the developed method could be of diagnostic value for Wilson disease, and possibly other copper related diseases.
AU  - Quarles, C.D.*
AU  - Macke, M.*
AU  - Michalke, B.
AU  - Zischka, H.
AU  - Karst, U.*
AU  - Sullivan, P.*
AU  - Field, M.P.*
C1  - 60177
C2  - 49287
CY  - Thomas Graham House, Science Park, Milton Rd, Cambridge Cb4 0wf, Cambs, England
SP  - 1348-1355
TI  - LC-ICP-MS method for the determination of "extractable copper" in serum.
JO  - Metallomics
VL  - 12
IS  - 9
PB  - Royal Soc Chemistry
PY  - 2020
SN  - 1756-5901
ER  - 

TY  - JOUR
AB  - Amyotrophic lateral sclerosis is a progressive neurodegenerative disease characterized by a loss of function of motor neurons. The etiology of this disorder is still largely unknown. Gene-environment interaction arises as a possible key factor in the development of amyotrophic lateral sclerosis. We assessed the levels of trace metals, copper (Cu), iron (Fe), and manganese (Mn), of 9 amyotrophic lateral sclerosis cases and 40 controls by measuring their content in cerebrospinal fluid. The following trace element species were quantified using ion chromatography-inductively coupled plasma mass spectrometry: univalent copper (Cu-I), divalent Cu (Cu-II), divalent Fe (Fe-II), trivalent Fe (Fe-III), divalent Mn (Mn-II), trivalent Mn (Mn-III), and also unidentified Mn species (Mn-unknown) were present in some samples. When computing the relative risks for amyotrophic lateral sclerosis through an unconditional logistic regression model, we observed a weak and imprecise positive association for iron (Fe III, adjusted odds ratio 1.48, 95% CI 0.46-4.76) and manganese (total-Mn and Mn-II; adjusted odds ratio 1.11, 95% CI 0.74-1.67, and 1.13, 95% CI 0.79-1.61, respectively). Increased risk for copper was found both in the crude analysis (odds ratio 1.14, 95% CI 0.99-1.31) and in multivariable analysis after adjusting for sex, age, and year of storage (1.09, 95% CI 0.90-1.32). Our results suggest a possible positive association between Cu and genetic amyotrophic lateral sclerosis, while they give little indication of involvement of Fe and Mn in disease, though some correlations found also for these elements deserve further investigation.
AU  - Violi, F.*
AU  - Solovyev, N.
AU  - Vinceti, M.*
AU  - Mandrioli, J.*
AU  - Lucio, M.
AU  - Michalke, B.
C1  - 59034
C2  - 48490
CY  - Thomas Graham House, Science Park, Milton Rd, Cambridge Cb4 0wf, Cambs, England
SP  - 668-681
TI  - The study of levels from redox-active elements in cerebrospinal fluid of amyotrophic lateral sclerosis patients carrying disease-related gene mutations shows potential copper dyshomeostasis.
JO  - Metallomics
VL  - 12
IS  - 5
PB  - Royal Soc Chemistry
PY  - 2020
SN  - 1756-5901
ER  - 

TY  - JOUR
AB  - Copper homeostasis is strictly regulated in mammalian cells. We investigated the adaptation of hepatocytes after long-term copper exposure. Copper-resistant hepatoma HepG2 cell lines lacking ATP7B were generated. Growth, copper accumulation, gene expression, and transport were determined. Hepatocyte-like cells derived from a Wilson disease (WD) patient and the liver of a WD animal model were also studied. The rapidly gained copper resistance was found to be stable, as subculturing of cells in the absence of added copper (weaning) did not restore copper sensitivity. Intracellular copper levels and the expression of MT1 and HSP70 were increased, whereas the expression of CTR1 was reduced. However, the values normalized after weaning. In contrast, downregulation of multi-drug resistance protein 1 (MDR1), encoding P-glycoprotein (P-gp), was shown to be permanent. Calcein assays confirmed the downregulation of MDR1 in the resistant cell lines. MDR1 knockdown by siRNA resulted in increased copper resistance and decreased intracellular copper. Treatment of the resistant cells with verapamil, a known inducer of MDR1, was followed by increased copper-induced toxicity. Downregulation of MDR1 was also observed in hepatocyte-like cells derived from a WD patient after copper exposure. In addition, MDR1 was downregulated in Long-Evans Cinnamon rats when the liver copper was elevated. The results indicate that downregulation of MDR1 is an adaptation of hepatic cells after sustained copper exposure when ATP7B is non-functional. Our data add to the versatile functions of MDR1 in the hepatocyte and may have an impact on the treatment of copper-related diseases, prominently WD.
AU  - Groba, S.R.*
AU  - Guttmann, S.*
AU  - Niemietz, C.*
AU  - Bernick, F.*
AU  - Sauer, V.*
AU  - Hachmöller, O.*
AU  - Karst, U.*
AU  - Zischka, H.
AU  - Zibert, A.*
AU  - Schmidt, H.H.*
C1  - 51718
C2  - 43468
CY  - Cambridge
SP  - 1279-1287
TI  - Downregulation of hepatic multi-drug resistance protein 1 (MDR1) after copper exposure.
JO  - Metallomics
VL  - 9
IS  - 9
PB  - Royal Soc Chemistry
PY  - 2017
SN  - 1756-5901
ER  - 

TY  - JOUR
AB  - A liver biopsy specimen from a Wilson's disease (WD) patient was analyzed by means of micro-X-ray fluorescence (μXRF) spectroscopy to determine the elemental distribution. First, bench-top μXRF was utilized for a coarse scan of the sample under laboratory conditions. The resulting distribution maps of copper and iron enabled the determination of a region of interest (ROI) for further analysis. In order to obtain more detailed elemental information, this ROI was analyzed by synchrotron radiation (SR)-based μXRF with a beam size of 4 μm offering a resolution at the cellular level. Distribution maps of additional elements to copper and iron like zinc and manganese were obtained due to a higher sensitivity of SR-μXRF. In addition to this, X-ray absorption near edge structure spectroscopy (XANES) was performed to identify the oxidation states of copper in WD. This speciation analysis indicated a mixture of copper(i) and copper(ii) within the WD liver tissue.
AU  - Hachmöller, O.*
AU  - Buzanich, A.G.*
AU  - Aichler, M.
AU  - Radtke, M.*
AU  - Dietrich, D.*
AU  - Schwamborn, K.*
AU  - Lutz, L.*
AU  - Werner, M.*
AU  - Sperling, M.*
AU  - Walch, A.K.
AU  - Karst, U.*
C1  - 48166
C2  - 39940
CY  - Cambridge
SP  - 648-653
TI  - Elemental bioimaging and speciation analysis for the investigation of Wilson's disease using μXRF and XANES.
JO  - Metallomics
VL  - 8
IS  - 7
PB  - Royal Soc Chemistry
PY  - 2016
SN  - 1756-5901
ER  - 

TY  - JOUR
AB  - Occupationally or environmentally caused chronic exposure to Manganese (Mn) can lead to a degeneration of dopaminergic neurons inducing a Parkinson-like complaint called manganism. Deciphering the ongoing neurodegenerative mechanisms in the affected brain is still a major task for understanding the complex modes of action. Therefore, we applied a non-toxic, oral feeding in rats simulating a chronic exposure to Mn. Analysis of brain extracts by electrospray ionization Fourier transform resonance mass spectrometry (ESI-FT-ICR-MS) revealed an increase in markers of oxidative stress like glutathione disulfide (GSSG), prostaglandins, and 15(S)-HETE, a marker of lipid peroxidation. Furthermore, acetylcholinesterase (AchE) activity and glutamate concentrations were elevated in brain samples of Mn-supplemented rats, suggesting oxidative stress in the brain tissue. Application of ion chromatography coupled to inductively coupled plasma-optical emission spectrometry (IC-ICP-OES) further showed a shift of Fe(iii) towards Fe(ii) in the brain samples enabling for example the action of the Fenton reaction. This is the first time that changes in the Fe-species distribution could be related to Mn-induced neuroinflammation and is therefore enlarging the knowledge of this complex neurodegenerative condition. The combination of our findings provides substantial evidence that Mn-induced neuroinflammation leads to oxidative stress triggered by multifactorial pathophysiological processes.
AU  - Fernsebner, K.
AU  - Zorn, J.
AU  - Kanawati, B.
AU  - Walker, A.
AU  - Michalke, B.
C1  - 30879
C2  - 33980
CY  - Cambridge
SP  - 921-931
TI  - Manganese leads to an increase in markers of oxidative stress as well as to a shift in the ratio of Fe(ιι)/(ιιι) in rat brain tissue.
JO  - Metallomics
VL  - 6
IS  - 4
PB  - Royal Soc Chemistry
PY  - 2014
SN  - 1756-5901
ER  - 

TY  - JOUR
AB  - Typha latifolia is a plant species widely used for phytoremediation. Accumulation, localization and distribution of Pb and mineral nutrients were investigated in roots, rhizomes and leaves of Typha latifolia grown at 0, 50, 100 and 250 mu M Pb concentrations in a pot experiment under controlled conditions. Bulk elemental concentrations were determined by X-ray fluorescence (XRF) spectroscopy whereas micro-proton-induced X-ray emission (micro-PIXE) was used for element localization in root and rhizome tissues. Gradual increase in bulk Pb concentrations was observed in Typha latifolia roots and rhizomes treated with increasing Pb concentrations, however in rhizomes Pb concentrations were an order of magnitude lower than in roots. In leaves Pb concentrations were around the limit of detection for XRF (similar to 20 mu g g(-1)). An increase in concentration of K and Ca in roots, rhizomes and leaves, of iron and zinc in roots and leaves, and of Mn in rhizomes was observed either at 50 and/or 100 mu M Pb treatments, whereas for K and Ca in roots, rhizomes and leaves, Fe and Zn in roots and leaves and Mn in rhizomes, or at 250 mu M Pb treatment the increase was seen for concentrations of Fe and Zn in rhizomes and Cu in roots. Mn concentrations decreased with Pb treatments in roots and leaves. Element localization using micro-PIXE analysis demonstrated Pb accumulation in epidermal and cortical tissues of treated roots and rhizomes, while in endodermis and vascular tissues Pb was not detected. A displacement of Ca from epidermal to cortical tissues was observed in Pb treated roots and rhizomes, pointing to cell wall immobilization of Pb as one of the tolerance mechanisms in Typha latifolia. High level of colocalization of Pb with P (r = 0.60), S (r = 0.37) and Zn (r = 0.70) was observed in Pb treated roots, while in rhizomes colocalization with the mentioned elements was still positive, but not that prominent. These results indicate that Pb may form complexes with phosphorus and sulfur compounds in roots and rhizomes, which may also represent attraction sites for binding Zn. Because of its large root and rhizome surface area acting as main sites for Pb adsorption, Typha latifolia may represent potentially efficient plant species for phytoremediation of Pb contaminated soils and waters.
AU  - Lyubenova, L.
AU  - Pongrac, P.*
AU  - Vogel-Mikus, K.*
AU  - Mezek, G.K.*
AU  - Vavpetic, P.*
AU  - Grlj, N.*
AU  - Kump, P.*
AU  - Necemer, M.*
AU  - Regvar, M.*
AU  - Pelicon, P.*
AU  - Schröder, P.
C1  - 7990
C2  - 29943
SP  - 333-341
TI  - Localization and quantification of Pb and nutrients in Typha latifolia by micro-PIXE.
JO  - Metallomics
VL  - 4
IS  - 4
PB  - Royal Soc. Chemistry
PY  - 2012
SN  - 1756-5901
ER  -