Quercetin Improves Glucose and Lipid Metabolism of Diabetic Rats: Involvement of Akt Signaling and SIRT1

Figure 2

Quercetin treatment enhanced hepatic SIRT1 protein expression and deacetylase activity in STZ-induced diabetic rats. The effects of quercetin on hepatic SIRT1 expression levels in the livers of control, diabetes, QU-low, QU-high, and pioglitazone-treated rats were detected through immunohistochemistry. Staining without SIRT1 antibody was used as a negative control. (a and b) Original magnification of 400x, solid arrow indicates nuclear SIRT1, and hollow arrow corresponds to cytoplasmic SIRT1. (c) Western blot. Immunohistochemistry showed SIRT1 (dark brown) was decreased in diabetes compared with control and was partially increased by the quercetin treatment. (d) Hepatic SIRT1 deacetylase activity in rat livers was detected using a fluorometric assay kit. Data are means ± SD, . versus control group and ^# versus diabetic group by ANOVA.

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