杨梅黄酮通过Wnt通路改善细胞因子诱导的胰岛β细胞功能障碍的实验研究(英文)

Upregulation of Wnt Signal Pathway by Myricetin Attenuates β-Cell Dysfunction Induced by Cytokines

本文探讨杨梅黄酮对细胞因子诱导的胰岛β细胞功能障碍的影响及Wnt通路在其中的作用.MTT法检测细胞的存活率;放射免疫法检测RIN-m5fβ细胞在基础状态和高糖状态下胰岛素的分泌水平;Western blot法检测Wnt通路相关蛋白的表达情况.肿瘤坏死因子α、白介素1β和γ干扰素联合作用细胞48 h后,与空白对照组相比,细胞的存活率显著下降;基础状态下胰岛素的分泌量增加至空白对照组的2.45倍,而高糖刺激状态下胰岛素的分泌量减少至空白对照组的39.6%.Western blot结果显示,细胞因子处理后使Wnt通路相关蛋白的表达量下降.而杨梅黄酮作用后,与细胞因子组相比,可使细胞存活率上升.另外,20μmol/L杨梅黄酮可逆转细胞因子对胰岛素分泌的影响,使基础状态下胰岛素的分泌减少,高糖刺激状态下胰岛素分泌量显著增加.Western blot结果显示,杨梅黄酮提高了Wnt通路相关蛋白的表达水平.上述结果表明,细胞因子联合作用48 h能诱导RIN-m5f细胞功能障碍,杨梅黄酮干预后能减少这种细胞损伤,保护机制可能与其激活Wnt通路有关.

We examined the effect of myricetin on cell dysfunction in cytokine-induced pancreatic β cells and assessed whether Wnt signal pathway was the target of myricetin.RIN-m5f β cells were exposed to a combination of tumor necrosis factor-α,interleukin-1β,and interferon-γ,with or without myricetin pretreatment for 48 h.The cell viability,basal and glucose-stimulated insulin secretion and Wnt-signaling proteins were evaluated with methyl thiazolyl tetrazolium assay,radio immunoassay and Western blotting,respectively.The 48 h multiple-cytokine treatment decreased cell viability and glucose-stimulated insulin secretion,while increasing basal insulin secretion.Western blot analysis showed that Wnt-signaling proteins were decreased in cytokine-treated RIN-m5f cells.However,myricetin pretreatment protected against cytokine-induced cell death.In addition,myricetin（20 μmol/L） obviously decreased basal insulin secretion and increased glucose-stimulated insulin secretion in cytokine-treated RIN-m5f cells.Western blot analysis showed that Wnt-signaling proteins were increased after myricetin pretreatment.Therefore,myricetin might attenuate cell dysfunction in cytokine-induced RIN-m5F cells via the Wnt signal pathway,and the Wnt signal pathway might be used as a new target for protecting pancreatic β cells against cytokine-induced cell dysfunction and death.