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Updated: Sep 29, 2026

Measuring the Rate of Lipolysis in Ex Vivo Murine Adipose Tissue and Primary Preadipocytes Differentiated In Vitro
Published on: March 17, 2023
PPAR alpha is necessary for the lipopenic action of hyperleptinemia on white adipose and liver tissue
Y Lee1, X Yu, F Gonzales
1Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
Abstract:
Adenovirus-induced hyperleptinemia causes rapid disappearance of body fat in normal rats, presumably by up-regulating fatty acid oxidation within white adipocytes. To determine the role of peroxisomal proliferation-activated receptor (PPAR)alpha expression, which was increased during the rapid loss of fat, we infused adenovirus-leptin into PPAR alpha(-/-) and PPAR alpha(+/+) mice. Despite similar degrees of hyperleptinemia and reduction in food intake, epididymal fat pad weight declined 55% in wild-type but only 6% in PPAR alpha(-/-) mice; liver triacylglycerol fell 39% in the wild-type group but was unchanged in PPAR(-/-) mice. Carnitine palmitoyl transferase-1 mRNA rose 52% in the wild-type mice but did not increase in PPAR alpha(-/-) mice. PPAR gamma coactivator-1 alpha rose 3-fold in the fat and 46% in the liver of wild-type mice but was unchanged in PPAR alpha(-/-) mice. Although AMP-activated protein kinase could not be implicated in the lipopenic actions of hyperleptinemia, acetyl CoA carboxylase protein was reduced in the liver of wild-type but not in PPAR alpha(-/-) mice. Thus, in PPAR alpha(-/-) mice, up-regulation of carnitine palmitoyl transferase-1 mRNA in fat, down-regulation of acetyl CoA carboxylase in liver, and up-regulation of PPAR gamma coactivator-1 alpha mRNA in both tissues are abolished, as is the reduction in their triacylglycerol content.
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