Mangiferin ameliorates insulin resistance in a rat model of polycystic ovary syndrome via inhibition of inflammation.

Purpose: To examine the effect of mangiferin on insulin resistance (IR) in a rat polycystic ovary syndrome (PCOS) model. Methods: The rat PCOS model was established via subcutaneous injection of 6 mg/kg of dehydroepiandrosterone (DHEA), and mangiferin was orally administered. Body and ovarian weights were recorded. Serum levels of glucose, insulin, and related inflammatory cytokines were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay, while the expression levels of key proteins were analyzed by western blotting. Results: DHEA significantly increased ovarian weight and the ratio of ovarian weight/body weight (p < 0.001), while mangiferin treatment decreased them (p < 0.001). Mangiferin also lowered DHEA-induced enhancements in serum glucose and insulin levels (p < 0.001). The mRNA and, expression and concentrations of inflammatory cytokines (interleukin-6(IL-6), interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α)) were also significantly reduced by mangiferin treatment (p < 0.001). Furthermore, mangiferin suppressed phosphorylation of nuclear factor-kappa B (NF-kB) but increased the phosphorylation of protein kinase B (AKT, p < 0.001). Conclusion: These results reveal that mangiferin not only decreases inflammatory cytokine levels by regulating NF-kB signaling pathway but also ameliorates IR in a rat PCOS model via regulating AKT signaling pathway. Thus, mangiferin is a potential therapeutic strategy for the management of PCOS. [ABSTRACT FROM AUTHOR]