He, M.* ; Ding, M.* ; Chocholoušková, M.* ; Chin, C.F.* ; Engvall, M.* ; Malmgren, H.* ; Wagner, M. ; Lauffer, M.C.* ; Heisinger, J.* ; Malicdan, M.C.V.* ; Allamand, V.* ; Durbeej, M.* ; Delgado-Vega, A.M.* ; Sejersen, T.* ; Nordgren, A.* ; Torta, F.* ; Silver, D.L.*
SPNS1 variants cause multi-organ disease and implicate lysophospholipid transport as critical for mTOR-regulated lipid homeostasis.
J. Clin. Invest. 135:e193099 (2025)
SPNS1 is a lysosomal transporter mediating the salvage of lysoglycerophospholipids, the degradative products of lysosomal phospholipid catabolism. However, a role of lysolipid transport and salvage in regulating cellular lipid homeostasis and in disease is lacking. Here, we identified two families with biallelic SPNS1 loss-of-function variants that presented primarily with progressive liver and striated muscle injury. Patient fibroblasts accumulated lysophospholipids including lysoplasmalogens and cholesterol in lysosomes with reduced cellular plasmalogens. Notably, SPNS1 deficiency resulted in reduced biogenesis of cytosolic lipid droplets containing triglycerides and cholesteryl esters. Mechanistically, we found that lysophospholipids transported by SPNS1 into the cytosol quantitatively contributed to triglyceride synthesis while lysosomal buildup of lyso-ether-phospholipid inhibited lysosomal cholesterol egress, effects that were enhanced with inhibition of mTOR. These findings support a gene-disease association and reveal connectivity between lysosomal transport of lysophospholipids and storage of reserve cellular energy as triglyceride and in the regulation of cholesterol homeostasis, processes that become important under nutrient limitation.
Impact Factor
Scopus SNIP
Web of Science
Times Cited
Scopus
Cited By
Altmetric
Publication type
Article: Journal article
Document type
Scientific Article
Thesis type
Editors
Keywords
Cell Biology ; Cholesterol ; Lipidomics ; Lysosomes ; Metabolism
Keywords plus
Language
english
Publication Year
2025
Prepublished in Year
0
HGF-reported in Year
2025
ISSN (print) / ISBN
0021-9738
e-ISSN
1558-8238
ISBN
Book Volume Title
Conference Title
Conference Date
Conference Location
Proceedings Title
Quellenangaben
Volume: 135,
Issue: 17,
Pages: ,
Article Number: e193099
Supplement: ,
Series
Publisher
American Society of Clinical Investigation
Publishing Place
Day of Oral Examination
0000-00-00
Advisor
Referee
Examiner
Topic
University
University place
Faculty
Publication date
0000-00-00
Application date
0000-00-00
Patent owner
Further owners
Application country
Patent priority
Reviewing status
Peer reviewed
POF-Topic(s)
30205 - Bioengineering and Digital Health
Research field(s)
Genetics and Epidemiology
PSP Element(s)
G-503200-001
Grants
Copyright
Erfassungsdatum
2025-07-16