The influence of eicosapentaenoic acid and docosahexaenoic acid on expression of genes connected with metabolism and secretory functions of ageing 3T3-L1 adipocytes

Abstract

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are n-3 long chain polyunsaturated fatty acids. The purpose of our study was to evaluate the influence of EPA and DHA on expression of genes connected with metabolism and secretory functions of ageing adipocytes. Young, mature and old differentiated 3T3-L1 adipocytes were cultured for 48h in the presence of EPA, or DHA. Both fatty acids increased the expression of Pparg, FATP1, FATP4 and ATGL genes, but only in young 3T3-L1 adipocytes. Moreover, in young, mature and old cells DHA elevated the expression of CPT1 gene. In addition, EPA and DHA enhanced the expression of leptin, adiponectin and apelin genes only in young cells. Investigated fatty acids changed mRNA levels of IL6 and MCP1 in young, mature and old cells. EPA increased the expression of these two genes, whereas DHA decreased it. Furthermore, EPA and DHA treatment changed the expression of IRS1 and GLUT4 genes involved in insulin signalling pathway, but their effects were opposite. Expression of these genes was decreased by EPA and increased by DHA in young, mature and old cells. In summary, the investigated fatty acids are able to affect the expression of genes associated with lipid metabolism, secretory functions and insulin resistance in ageing 3T3-L1 adipocytes, but their impact is age-dependant. Young cells seem to be more sensitive to EPA and DHA than mature and old ones. Furthermore, the effect of these two fatty acids is not always identical, and therefore requires further investigation.