Abstract: Abstract: Objective To study the effects of berberine (BBR) on the gene mRNA expression of fat-specific protein 27 (FSP27) and PR domain containing 16 (PRDM16) signal pathway in visceral white adipose tissues (VWAT) from type 2 diabetic (T2DM) Chinese hamsters and explore the related mechanisms. Methods The obese insulin-resistant (OIR) hamster models were induced by high-fat diet and T2DM hamster models were created by OIR hamster models injected with low-dose streptozotocin, the control group hamsters were fed with standard laboratory chow. After the induction, the hamsters were randomly divided into control, OIR, obese T2DM and BBR-treated T2DM groups. After nine-week BBR treatment, real-time quantitative PCR was used to measure the gene mRNA expression changes of VWAT FSP27 and PRDM16 signal pathway and their target genes from different groups. Results Compared with control group, the gene mRNA expression of PRDM16, CtBP-1, CtBP-2, C/EBPβ, PPARγ, PGC1α, PGC-1β and brown adipose tissue-specific genes such as UCP-1, Cidea, Elovl3, PPARα, and Acox, Cpt1 and Acadm was decreased and that of FSP27 and white adipose tissue-specific genes including Resistin、MEST and Serpina3k was increased in VWAT from hamsters of OIR and obese T2DM groups. BBR treatment down-regulated FSP27 expression, enhanced PRDM16 signal pathway, and induced the gene mRNA expression of brown adipose tissue-specific genes in VWAT from obese T2DM group to develop browning gene phenotype of visceral white adipose tissues, and then improved fat-induced insulin resistance. Conclusion Decreased VWAT FSP27 expression and increased VWAT PRDM16 expression involved in the molecular mechanisms of browning of visceral white adipose tissues induced by BBR, and contributed to improve abnormal lipids metabolism and fat-induced insulin resistance in VWAT by enhancing consumption of energy as heat to restore VWAT function.

Key words: Key words: berberine, type 2 diabetes, browning of white adipose tissues, insulin resistance, FSP27