番石榴叶提取物调节白色脂肪组织棕色化作用机制研究

目的:探究番石榴叶提取物调节脂肪细胞分化的作用机制。方法:6周龄雄性SPF级db/db小鼠24只、同龄C57BL/6J正常组小鼠6只,将符合纳入标准的db/db小鼠根据体重、血糖随机分为模型组和番石榴叶提取物高剂量组、番石榴叶提取物中剂量组、番石榴叶提取物低剂量组,并将番石榴叶提取物按高、中、低剂量进行灌胃,于4周后空腹脱臼处死所有小鼠,分别取后腿腓肠肌组织、皮下脂肪组织进行原代成肌细胞、原代脂肪组织SVF细胞的培养、接种和传代。培养48 h后收集细胞并提取蛋白,Western blot法检测各组成肌细胞PGC-1α、FNDC5蛋白和各组脂肪组织SVF细胞Prdm16蛋白的表达。结果:第4周时,与模型组小鼠相比,番石榴叶提取物高剂量组小鼠体重、血糖、低密度脂蛋白降低(均P<0.05)。番石榴叶提取物高剂量组小鼠成肌细胞PGC-1α、FNDC5蛋白表达升高,脂肪组织SVF细胞Prdm16蛋白表达较模型组升高(均P<0.05)。结论:番石榴叶提取物高剂量可通过促进白色脂肪细胞向棕色脂肪细胞分化,提高棕色脂肪水平,从而通过增加机体的能量代谢来调节脂质代谢。

Study on the mechanism of regulating browning of white adipose tissue of guava leaf extract

Objective:To explore the mechanism of guava leaf extractions regulating adipocyte differentiation.Methods:24 male SPF db/db mice of 6-week-old and 6 C57BL/6J mice of the same age were purchased for experimentation.The C57BL/6J mice were as normal group.While,the db/db mice which satisfy the inclusion criteria were randomly and equally divided into four groups according to body weight and blood glucose,namely,model group,high-dose guava leaf extractions group,medium-dose guava leaf extractions group,and low-dose guava leaf extractions group.The mice in the guava leaf extractions groups were intragastrically administered at high,medium and low doses respectively.All mice were killed by fasting dislocation after 4 weeks.Next,Primary myoblasts and primary adipose tissue SVF cells from hind leg gastrocnemius muscle tissue and subcutaneous adipose tissue were cultured,inoculated and passaged.After 48 hours of culture,the cells were collected and the protein was extracted.Western blot was used to detect the expression of PGC-1α,FNDC5 protein in myoblasts and Prdm16 protein in adipose tissue SVF cells.Results:Compared with mice in the model group,the body weight,blood glucose and LDL of mice in the high-dose guava leaf extractions group were reduced(all P<0.05).The protein expression of PGC-1αand FNDC5 in myoblasts of mice in the high-dose guava leaf extract group was increased,and the protein expression of Prdm16 in adipose tissue SVF cells was higher than that of the model group(all P<0.05).Conclusion:High-dose guava leaf extractions can increase the level of brown fat by promoting the differentiation of white fat cells into brown fat cells,thereby regulating lipid metabolism by increasing the body’s energy metabolism.