Fat-specific transgenic expression of resistin in the spontaneously hypertensive rat impairs fatty acid re-esterification

Objective: To investigate the mechanism by which fat-specific transgenic expression of resistin affects fatty acid metabolism in the spontaneously hypertensive rat (SHR). Design: Basal- and adrenaline-stimulated lipolysis, basal- and insulin-stimulated lipogenesis as well as the site (glycerol versus acyl moiety) of glucose incorporated into triglycerides were determined in adipose tissue isolated from SHR-Resistin transgenic and SHR control rats. Results: A moderate expression of transgenic resistin in adipose tissue was associated with significant increase in the FFA/glycerol ratio during adrenaline-stimulated lipolysis in the SHR-Resistin transgenic rats (3.27±0.26) compared to SHR controls (2.11±0.10, P =0.0005). Transgenic SHR also exhibited a significant decrease in FFA re-esterification in adipose tissue (approximately by 23%). Conclusion: These findings raise the possibility that the prodiabetic effects of transgenic resistin may be partly mediated by increased FFA release from adipose tissue due to impaired FFA re-esterification in adipocytes.