Effects of long-term starvation and refeeding on fatty acid metabolism-related gene expressions in the liver of zebrafish, Danio rerio

Abstract

A 70-day starvation was conducted to determine the effects of long-term starvation on whole-body polyunsaturated fatty acid (PUFA) composition and fatty acid metabolism-related gene expression in the liver of zebrafish, Danio rerio. The starvation period was followed by a 15-day refeeding period to test recovery of both PUFA composition and gene expression levels. It was found that n-3 PUFA and arachidonic acid levels increased during starvation and returned to normal values after refeeding (P < 0.05). Expression of seven (elovl5, fads2, cpt1-ß, acox1, acadvl, fabp1a, and fabp7a) of eight total genes downregulated significantly towards the end of the starvation. As a result of refeeding, gene expression of elovl5 and ppar-a returned to the normal levels. Therefore, it was concluded that, in general, mRNA expression of genes involved in fatty acid metabolism was negatively influenced by long-term starvation (70 days); there was no direct relationship between whole-body fatty acid composition and hepatic gene expressions; and 15-day refeeding was insufficient for recovery of starvation-based metabolic losses in zebrafish.