BCATm and BCKDH expression in mouse adipose tissue upon different metabolic challenges

Abstract

Branched chain amino acids (BCAA) are also catabolized in adipose tissue. The first two enzymatic steps of this process are catalyzed by the mitochondrial branched‐chain aminotransferase (BCATm) and the branched‐chain ‐keto acid dehydrogenase complex (BCKDC). There is evidence that these enzymes in adipose tissue may play a role during obesity, however, there is scarce knowledge about the regulation of the expression of these enzymes in this tissue. Thus, we have evaluated the expression of BCATm and BCKDH in adipose tissue of mouse after fasting or 4 h feeding a 6, 20 or 50% protein diets. In addition, we studied the expression of BCATm and BCKDH in adipose tissue of mice fed a high fat diet for 2 months, as well as the treatment with pioglitazone for one month, an activator of PPARγ, the master regulator of adipogenesis. Interestingly, BCATm and BCKDH mRNA abundance was significantly increased upon refeeding independently of the amount of dietary protein consumed. Similarly, treatment with pioglitazone, increased the BCATm and BCKDH mRNA abundance. However, BCATm and BCKDH mRNA abundance was significantly reduced upon High‐fat feeding. These data demonstrate that BCATm and BCKDH expression are transcriptionally modulated in mouse adipose tissue, possibly in part mediated via PPARγ (Supported by CONACYT).