Direct adipotropic actions of atorvastatin: differentiation state-dependent induction of apoptosis, modulation of endocrine function, and inhibition of glucose uptake.
Statins exert anti-inflammatory, anti-atherogenic actions. The mechanisms responsible for these effects remain only partially elucidated. Diabetes and obesity are characterized by low-grade inflammation. Metabolic and endocrine adipocyte dysfunction is known to play a crucial role in the development of these disorders and the related cardiovascular complications. Thus, direct modulation of adipocyte function may represent a mechanism of pleiotropic statin actions. We investigated effects of atorvastatin on apoptosis, differentiation, endocrine, and metabolic functions in murine white and brown adipocyte lines. Direct exposure of differentiating preadipocytes to atorvastatin strongly reduced lipid accumulation and diminished protein expression of the differentiation marker CCAAT/enhancer binding protein-beta (CEBP-beta). In fully differentiated adipocytes, however, lipid accumulation remained unchanged after chronic atorvastatin treatment. Furthermore, cell viability was reduced in response to atorvastatin treatment in proliferating and differentiating preadipocytes, but not in differentiated cells. Moreover, atorvastatin induced apoptosis and inhibited protein kinase B (AKT) phosphorylation in proliferating and differentiating preadipocytes, but not in differentiated adipocytes. On the endocrine level, direct atorvastatin treatment of differentiated white adipocytes enhanced expression of the pro-inflammatory adipokine interleukin-6 (IL-6), and downregulated expression of the insulin-mimetic and anti-inflammatory adipokines visfatin and adiponectin. Finally, these direct adipotropic endocrine effects of atorvastatin were paralleled by the acute inhibition of insulin-induced glucose uptake in differentiated white adipocytes, while protein expression of the thermogenic uncoupling protein-1 (UCP-1) in brown adipocytes remained unchanged. Taken together, our data for the first time demonstrate direct differentiation state-dependent effects of atorvastatin including apoptosis, modulation of pro-inflammatory and glucostatic adipokine expression, and insulin resistance in adipose cells. These differential interactions may explain variable clinical observations.
Mäuser
Wanda
W
Department of Internal Medicine I, University of Schleswig-Holstein, Campus Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany.
Perwitz
Nina
N
Meier
Britta
B
Fasshauer
Mathias
M
Klein
Johannes
J
D052437:Adipocytes, Brown / Q000187:drug effects* / Q000378:metabolism; D052438:Adipocytes, White / Q000187:drug effects* / Q000378:metabolism; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D000069059:Atorvastatin; D022782:CCAAT-Enhancer-Binding Protein-beta / Q000187:drug effects / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004703:Endocrine System / Q000187:drug effects; D005786:Gene Expression Regulation; D005947:Glucose / Q000378:metabolism; D006538:Heptanoic Acids / Q000494:pharmacology*; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology*; D015151:Immunoblotting; D018836:Inflammation Mediators / Q000378:metabolism; D007333:Insulin Resistance; D007473:Ion Channels / Q000187:drug effects; D051379:Mice; D024101:Mitochondrial Proteins / Q000187:drug effects; D010766:Phosphorylation; D051057:Proto-Oncogene Proteins c-akt / Q000187:drug effects / Q000378:metabolism; D011758:Pyrroles / Q000494:pharmacology*; D000071256:Uncoupling Protein 1
D022782:CCAAT-Enhancer-Binding Protein-beta; D006538:Heptanoic Acids; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D018836:Inflammation Mediators; D007473:Ion Channels; D024101:Mitochondrial Proteins; D011758:Pyrroles; C000604372:Ucp1 protein, mouse; D000071256:Uncoupling Protein 1; D000069059:Atorvastatin; D051057:Proto-Oncogene Proteins c-akt; D005947:Glucose