Medium‐Chain Fatty Acids Attenuate Agonist‐Stimulated Lipolysis, Mimicking the Effects of Starvation

Abstract

Results: Pretreatment of adipocytes with octanoate in vitro increased basal lipolysis but decreased the cellular response for agonists. The same effects were seen in starvation in vivo. Preincubation with octanoate for 48 hours did not affect basal lipase activity, HSL, and perilipin protein levels, but it reduced agonist-stimulated perilipin phosphorylation and HSL translocation toward fat droplets. This was associated with a reduction in basal cellular adenosine triphosphate levels and agonist-stimulated cyclic adenosine monophosphate generation. Starvation and octanoate pretreatment both increased intracellular H 2 O 2 concentrations, which might also contribute to the inhibition on agoniststimulated lipolysis. Discussion: Pretreatment with octanoate seems to induce changes in adipocyte lipolysis in a pattern mimicking the effects of starvation. Such changes could contribute, in part, to weight loss in animals and humans associated with dietary medium-chain FAs.

Regulation of adipogenesis by medium-chain fatty acids in the absence of hormonal cocktail

“…Octanoate was reported to increase basal lipolysis and to facilitate triglyceride hydrolysis in adipocytes [23]. Moreover, triglycerides containing MCFA were shown to be hydrolyzed more rapidly by HSL or LPL than triglycerides containing long-chain fatty acids [24,25], indicating that MCFA treatment of adipocytes might affect the expression of HSL and LPL.…”

Suppression of adipose lipolysis by long-chain fatty acid analogs

“…As MEDICA analogs simulate the characteristics of LCFA in terms of AMPK activation ( 12 ) and in inducing UPR ( 27,28 ), we may assume that the mode of action proposed for MEDICA may account, at least partially, for inhibition of agonist-induced lipolysis by LCFA ( 4,5 ). In light of AMPK activation by metformin or octanoate ( 31,32 ), the proposed transduction pathway may also offer a mode of action for the recently reported activity of metformin ( 31 ) or octanoate ( 32 ) in suppressing isoproterenol-induced lipolysis in primary rat adipocytes or 3T3-L1 adipocytes, respectively.…”

Triglyceride with Medium-Chain Fatty Acids Increases the Activity and Expression of Hormone-Sensitive Lipase in White Adipose Tissue of C57BL/6J Mice

“…31) MCT has been reported to enhance the expression of LPL, which increased basal lipolysis and facilitated triglyceride hydrolysis in adipocytes in post-confluent 3T3-L1 preadipocytes. 32) Triglycerides containing MCFAs have also been shown to be hydrolyzed more rapidly by LPL than triglycerides containing LCFAs, 33) indicating that MCT might have affected the level and/or expression of LPL. Although no significant difference in the levels of LPL in WAT was apparent in this study between the MCT and LCT groups, a decreased level of serum TG was found in C576J/BL mice fed with MCT (Table 7).…”