Gene expression profile of high-fat diet-fed C57BL/6J mice: in search of potential role of azelaic acid

Abstract

High-fat diet (HFD) elevates circulatory fatty acids and influences glucose and fat metabolism. Azelaic acid (AzA), a naturally occurring α,ω-dicarboxylic acid in wheat, rye, barley, oat seeds and sorghum, has been reported to exert antidiabetic effects in HFD-induced type 2 diabetes mellitus (T2DM) C57BL/6J mice. The present study was undertaken to identify the genes that are differentially modulated by treatment with AzA in HFD-fed mice. Mice were fed HFD for 10 weeks and subjected to intragastric administration of 80 mg/kg body weight (BW) of AzA daily along with HFD from 11 to 15 weeks. Lipid profile, adipokines and cytokines were examined in the plasma/liver of mice. Whole genome profiling was performed in the liver of mice using microarray and validated by qRT-PCR, Western blot and immunohistochemical analyses. HFD intake resulted in significantly elevated lipids (except high-density lipoproteins), resistin, tumour necrosis factor alpha and interleukin-6 with marked reduction in adiponectin. Administration of AzA to HFD-fed mice significantly restored the lipids, adipokines and cytokines to near normal. Transcript profiling revealed that HFD intake activated the genes involved in stress response, cell cycle regulation and apoptosis. Treatment with AzA caused increased expression of genes involved in reactive oxygen species (ROS) scavenging, receptor-mediated signalling, transcription, protein modification and insulin signal transduction. AzA activates insulin signal molecules leading to insulin sensitivity. The ability of AzA to modulate the expression of these genes supports the notion that AzA is a promising drug candidate for the treatment of insulin resistance associated with T2DM.