Octanoic acid promotes branched-chain amino acid catabolisms via the inhibition of hepatic branched-chain alpha-keto acid dehydrogenase kinase in rats.

Objective: It has been reported that administration of octanoic acid, one of medium-chain fatty acids (MCFAs), promoted leucine oxidation in vitro and in vivo, but it remained unclear how octanoic acid stimulated leucine oxidation. Therefore, the aim of this study was to elucidate the mechanism that octanoic acid facilitates branched-chain amino acid (BCAA) catabolism.

Materials/methods: In in vivo experiments, male rats were orally administered MCFAs as free fatty acids or triacylglycerol (trioctanoin), and then activities of hepatic branched-chain α-ketoacid dehydrogenase (BCKDH) complex (BCKDC) and BCKDH kinase (BDK) and alterations in the concentration of blood components were analyzed.