Altered mitochondrial function and metabolic inflexibility associated with loss of caveolin-1.
Caveolin-1 is a major structural component of raft structures within the plasma membrane and has been implicated as a regulator of cellular signal transduction with prominent expression in adipocytes. Here, we embarked on a comprehensive characterization of the metabolic pathways dysregulated in caveolin-1 null mice. We found that these mice display decreased circulating levels of total and high molecular weight adiponectin and a reduced ability to change substrate use in response to feeding/fasting conditions. Caveolin-1 null mice are extremely lean but retain muscle mass despite lipodystrophy and massive metabolic dysfunction. Hepatic gluconeogenesis is chronically elevated, while hepatic steatosis is reduced. Our data suggest that the complex phenotype of the caveolin-1 null mouse is caused by altered metabolic and mitochondrial function in adipose tissue with a subsequent compensatory response driven mostly by the liver. This mouse model highlights the central contributions of adipose tissue for system-wide preservation of metabolic flexibility.
Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-8549, USA.
Ingrid Wernstedt
IW
Asterholm
Dorothy I
DI
Mundy
Jian
J
Weng
Richard G W
RG
Anderson
Philipp E
PE
Scherer
D052242:Adiponectin / Q000097:blood; D000273:Adipose Tissue / Q000378:metabolism*; D000818:Animals; D051242:Caveolin 1 / Q000172:deficiency*; D005230:Fatty Acids, Nonesterified / Q000378:metabolism; D005234:Fatty Liver / Q000000981:diagnostic imaging; D005943:Gluconeogenesis / Q000502:physiology; D006652:Histological Techniques; D008099:Liver / Q000378:metabolism*; D053858:Metabolic Networks and Pathways / Q000502:physiology*; D051379:Mice; D008928:Mitochondria / Q000378:metabolism*; D014057:Tomography, X-Ray Computed
D052242:Adiponectin; D051242:Caveolin 1; D005230:Fatty Acids, Nonesterified