Curcumin interrupts leptin-regulated microRNA-122 in hepatic stellate cells in vitro and in vivo

The purpose of this study was to evaluate the effect of curcumin, an active polyphenol, on the leptin induced lowering of miR-122 in Hepatic stellate cells (HSCs) in vivo and an animal model. Gene expression was evaluated by transfection assay, real-time PCR, or Western blot analysis. The liver fibrosis model of leptin deficient mouse was used for in vivo experiment. As a result, curcumin showed inhibitory effect on leptin induced lowering of the miR-122 in HSCs. Curcumin suppressed leptin induced sonic hedgehog (Shh) expression and blocked leptin induced Shh signaling pathway, which was essential for curcumin inhibition of the negative role of leptin in miR-122 expression in HSCs. The influence of curcumin on the negative effect of leptin on miR-122 level was followed by the attenuation of liver fibrosis caused by leptin in leptin-deficient mouse model. In conclusion, curcumin could reduce the decrease of miR-122 level in HSCs induced by leptin and inhibit liver fibrosis induced by leptin. These data may have potential implications to treat with liver fibrosis by elevating the expression of leptin in humans especially obese patients.

Automated summary

The study aimed to assess the impact of curcumin, an active polyphenol, on the reduction of miR-122 in Hepatic stellate cells (HSCs) caused by leptin in vivo and in an animal model. Gene expression was assessed through transfection assay, real-time PCR, or Western blot analysis. A liver fibrosis model of leptin-deficient mice was used for the in vivo experiment. Curcumin demonstrated inhibition of the leptin-induced reduction of miR-122 in HSCs. It also suppressed the expression of sonic hedgehog (Shh) induced by leptin and blocked the Shh signaling pathway, which was crucial for curcumin's ability to inhibit the negative impact of leptin on miR-122 expression in HSCs. Curcumin's influence on the negative effect of leptin on miR-122 level was followed by the reduction of leptin-induced liver fibrosis in the leptin-deficient mouse model. Overall, curcumin may have potential implications for the treatment of liver fibrosis by increasing leptin expression, especially in obese patients.