Circulating sphingolipid biomarkers in models of type 1 diabetes.
Alterations in lipid metabolism may contribute to diabetic complications. Sphingolipids are essential components of cell membranes and have essential roles in homeostasis and in the initiation and progression of disease. However, the role of sphingolipids in type 1 diabetes remains largely unexplored. Therefore, we sought to quantify sphingolipid metabolites by LC-MS/MS from two animal models of type 1 diabetes (streptozotocin-induced diabetic rats and Ins2(Akita) diabetic mice) to identify putative therapeutic targets and biomarkers. The results reveal that sphingosine-1-phosphate (So1P) is elevated in both diabetic models in comparison to respective control animals. In addition, diabetic animals demonstrated reductions in plasma levels of omega-9 24:1 (nervonic acid)-containing ceramide, sphingomyelin, and cerebrosides. Reduction of 24:1-esterfied sphingolipids was also observed in liver and heart. Nutritional stress via a high-fat diet also reduced 24:1 content in the plasma and liver of mice, exacerbating the decrease in some cases where diabetes was also present. Subcutaneous insulin corrected both circulating So1P and 24:1 levels in the murine diabetic model. Thus, changes in circulating sphingolipids, as evidenced by an increase in bioactive So1P and a reduction in cardio- and neuro-protective omega-9 esterified sphingolipids, may serve as biomarkers for type 1 diabetes and represent novel therapeutic targets.
Department of Pharmacology, Penn State College of Medicine, Milton S. Hershey Medical Center, Hershey, PA, USA.
Todd E
TE
Fox
Maria C
MC
Bewley
Kellee A
KA
Unrath
Michelle M
MM
Pedersen
Robert E
RE
Anderson
Dae Young
DY
Jung
Leonard S
LS
Jefferson
Jason K
JK
Kim
Sarah K
SK
Bronson
John M
JM
Flanagan
Mark
M
Kester
D000483:Alleles; D000818:Animals; D015415:Biomarkers / Q000097:blood / Q000737:chemistry / Q000378:metabolism; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000378:metabolism; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000235:genetics / Q000378:metabolism; D004195:Disease Models, Animal; D005227:Fatty Acids / Q000097:blood; D005260:Female; D007328:Insulin / Q000235:genetics / Q000494:pharmacology; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008246:Lysophospholipids / Q000378:metabolism; D008297:Male; D051379:Mice; D009154:Mutation; D009206:Myocardium / Q000378:metabolism; D051381:Rats; D013107:Sphingolipids / Q000097:blood* / Q000737:chemistry / Q000378:metabolism; D013110:Sphingosine / Q000031:analogs & derivatives / Q000378:metabolism
D015415:Biomarkers; D005227:Fatty Acids; D007328:Insulin; D008246:Lysophospholipids; D013107:Sphingolipids; C060506:sphingosine 1-phosphate; D013110:Sphingosine