桑叶中对PPARγ有激活作用的组分分离和活性鉴定

Separation and Activity Identification of Mulberry Leaf Ingredients with Activating Ability to PPARγ

过氧化物酶体增殖物激活受体-γ(PPARγ)是调节脂肪细胞基因表达和分化的重要因子,也称作胰岛素增敏剂受体,一些脂肪酸对PPARγ有激活作用。桑叶中含有多种脂肪酸,以其为材料,利用构建的COS-7细胞高通量筛选模型筛选具有PPARγ配体活性的组分及单体。桑叶粉通过正己烷提取和石油醚萃取后,石油醚萃取组分(Fr.P)对PPARγ的激活倍数可达到阴性对照DMSO的3.34倍。经气相色谱-质谱(GC-MS)分析,从桑叶正己烷提取物(Fr.H)和Fr.P组分中共获得19种脂肪酸,其中Fr.H中的亚麻酸质量分数为1.91%,亚油酸为0.94%,十四酸为0.11%。高通量细胞筛选模型分析显示,与阴性对照DMSO比较,100μmol/L十四酸对PPARγ的激活倍数为1.51,50μmol/L十五酸对PPARγ的激活倍数为2.12,150μmol/L亚麻酸对PPARγ的激活倍数为2.48,100μmol/L亚油酸对PPARγ的激活倍数为2.21,而其他脂肪酸均无PPARγ配体活性。通过十四酸、亚麻酸和亚油酸的协同PPARγ激活效应分析,推测桑叶中可能含有非脂肪酸的PPARγ激动剂成分。研究结果提示有望从桑叶中寻找到新的天然胰岛素增敏剂。

Peroxisome proliferator-activated receptor-γ （PPARγ）, also known as insulin-sensitizing agent receptor, is an important factor which regulates the expression and differentiation of adipocyte gene. Some fatty acids can activate PPAR-γ. In present study, mulberry leaves which contain various fatty acids were used as material to screen the fractions and monomers with PPARγ ligand activity by the constructed COS-7 cellular high-throughput screening model. After mul- berry leaves were extracted with n-hexane and petroleum ether, the activation folds of mulberry leaf petroleum ether ex- traction fraction （Fr.P） to PPARγ ere 3.34 times to that of negative control （DMSO） to PPARγ. Altogether 19 kinds of fatty acids including linolenic acid （1.91%）, linoleic acid （0.94%）, and mysistic acid （0. 11%） were obtained from mulberry leaf n-hexane extract （Fr.H） and Fr.P by GC-MS analysis. COS-7 cellular high-throughput screening model analysis showed that the activation folds of 100μmol/L mysistic acid, 50 μmol/L pentadecanoic acid, 150μmol/L linole.