Adipose triglyceride lipase activity is inhibited by long-chain acyl-coenzyme A

作者：Nagy Harald M; Paar Margret; Heier Christoph; Moustafa Tarek; Hofer Peter; Haemmerle Guenter; Lass Achim; Zechner Rudolf; Oberer Monika; Zimmermann Robert^*

来源：Biochimica et Biophysica Acta-Molecular and Cell Biology of Lipids, 2014, 1841(4): 588-594.

DOI：10.1016/j.bbalip.2014.01.005

• Adipose triglyceride lipase
• Hormone-sensitive lipase
• Lipolysis
• Regulation
• acyl-CoA

Adipose triglyceride lipase (ATGL) is required for efficient mobilization of triglyceride (TG) stores in adipose tissue and non-adipose tissues. Therefore, ATGL strongly determines the availability of fatty acids for metabolic reactions. ATGL activity is regulated by a complex network of lipolytic and anti-lipolytic hormones. These signals control enzyme expression and the interaction of ATGL with the regulatory proteins CGI-58 and GOS2. Up to date, it was unknown whether ATGL activity is also controlled by lipid intermediates generated during lipolysis. Here we show that ATGL activity is inhibited by long-chain acyl-CoAs in a non-competitive manner, similar as previously shown for hormone-sensitive lipase (HSL), the rate-limiting enzyme for diglyceride breakdown in adipose tissue. ATGL activity is only marginally inhibited by medium-chain acyl-CoAs, diglycerides, monoglycerides, and free fatty acids. Immunoprecipitation assays revealed that acyl-CoAs do not disrupt the protein protein interaction of ATGL and its co-activator CGI-58. Furthermore, inhibition of ATGL is independent of the presence of CGI-58 and occurs directly at the N-terminal patatin-like phospholipase domain of the enzyme. In conclusion, our results suggest that inhibition of the major lipolytic enzymes ATGL and HSL by long-chain acyl-CoAs could represent an effective feedback mechanism controlling lipolysis and protecting cells from lipotoxic concentrations of fatty acids and fatty acid-derived lipid metabolites.

• 出版日期2014-4