芳香化酶在前脂肪细胞分化过程中的表达变化

摘要

Objective To observe the expression of aromatase during the process of preadipocyte differentiation.Methods Rat preadipocytes were cultured in vitro using collagenase-digesting method.Preadipocytes were induced to differentiate into adipocytes and identified by oil red O staining.Expression levels of aromatase and peroxisome proliferator-activated receptorγ (PPARγ) were detected by immunofluorescence staining and western blotting on the 0th,1st,2nd,3rd,4th and 5th days of differentiation.Results Preadipocytes were successfully cultured and induced to differentiate.Lipid droplets formed on the 3rd day of differentiation;large lipid droplets formed on the 6th day of differentiation;oil red O staining showed red-stained lipid droplets.Immunofluorescence staining showed that the expression level of aromatase gradually decreased during preadipocyte differentiation.Western blotting showed that the expression level of aromatase decreased and PPARγ expression increased during preadipocyte differentiation.Relative absorbance value of aromatase expression on the 2nd,3rd,4th,5th days of differentiation was significantly lower than that on the 0th day of differentiation [(0.518 ± 0.024),(0.263 ± 0.015),(0.327 ± 0.009),(0.164 ± 0.009) vs (0.753 ± 0.022)] (P ＜ 0.05).Relative absorbance value of PPARγexpression on the 2nd,3rd,4th,5th days of differentiation was significantly higher than that on the 0th day of differentiation (P ＜ 0.05).Conclusion Expression of aromatase gradually decreases during preadipocyte differentiation,which may be regulated by PPARγ.%目的 研究芳香化酶在前脂肪细胞分化过程中的表达变化,为高龄女性肥胖研究奠定实验基础.方法 采用胶原酶消化法体外培养大鼠前脂肪细胞,以分化培养基诱导分化,油红○染色进行细胞分化鉴定.分别在分化过程的第0、1、2、3、4、5天进行免疫荧光染色和蛋白免疫印迹实验检测芳香化酶和过氧化物酶体增殖物激活受体γ(PPARγ)的表达变化.结果 成功培养大鼠前脂肪细胞并诱导分化,诱导分化的第3天可见脂滴形成,分化第5天形成大的脂滴,油红○染色可见红染颗粒.免疫荧光染色可见芳香化酶在前脂肪细胞分化的过程中表达逐渐降低.蛋白免疫印迹实验证实前脂肪细胞分化过程中芳香化酶的蛋白表达水平下降,而PPARγ的蛋白表达水平上调.分化第2、3、4、5天芳香化酶蛋白表达相对吸光度值明显低于分化第0天[(0.518±0.024)、(0.263±0.015)、(0.327±0.009)、(0.164±0.009)比(0.753±0.022)],PPARγ蛋白表达相对吸光度值明显高于分化第0天,差异均有统计学意义(均P＜0.05).结论 芳香化酶在前脂肪细胞分化过程中表达逐渐降低,可能是由于分化过程中PPARγ表达上调而导致.