Insulin/Snail1 axis ameliorates fatty liver disease by epigenetically suppressing lipogenesis.
Yan LiuLin JiangChengxin SunNicole IrelandYatrik M ShahYong LiuLiangyou RuiPublished in: Nature communications (2018)
Insulin stimulates lipogenesis but insulin resistance is also associated with increased hepatic lipogenesis in obesity. However, the underlying mechanism remains poorly characterized. Here, we show a noncanonical insulin-Snail1 pathway that suppresses lipogenesis. Insulin robustly upregulates zinc-finger protein Snail1 in a PI 3-kinase-dependent manner. In obesity, the hepatic insulin-Snail1 cascade is impaired due to insulin resistance. Hepatocyte-specific deletion of Snail1 enhances insulin-stimulated lipogenesis in hepatocytes, exacerbates dietary NAFLD in mice, and attenuates NAFLD-associated insulin resistance. Liver-specific overexpression of Snail1 has the opposite effect. Mechanistically, Snail1 binds to the fatty acid synthase promoter and recruits HDAC1/2 to induce deacetylation of H3K9 and H3K27, thereby repressing fatty acid synthase promoter activity. Our data suggest that insulin pathways bifurcate into canonical (lipogenic) and noncanonical (anti-lipogenesis by Snail1) two arms. The noncanonical arm counterbalances the canonical arm through Snail1-elicited epigenetic suppression of lipogenic genes. Impairment in the insulin-Snail1 arm may contribute to NAFLD in obesity.
Keyphrases
- high fat diet induced
- type diabetes
- insulin resistance
- epithelial mesenchymal transition
- glycemic control
- metabolic syndrome
- adipose tissue
- high fat diet
- fatty acid
- polycystic ovary syndrome
- dna methylation
- weight loss
- skeletal muscle
- gene expression
- transcription factor
- cell proliferation
- weight gain
- amino acid
- body mass index
- data analysis
- protein kinase
- binding protein