Objective: To observe the effect of electroacupuncture on sexual development and ovarian estrogen receptor β(ER-β) expression in female adolescent obese rats induced by high-fat diet, so as to explore its underlying mechanisms of improving adolescent obesity.
Methods: Female SD rats (age of 21 days) were randomly divided into control, model and acupuncture groups, with 6 rats in each group. The obese model was established by feeding high-fat diet for 6 weeks. Rats of the acupuncture group received electroacupuncture(2 Hz, 0.5-1.2 mA)stimulation at bilateral "Sanyinjiao"(SP6), "Fenglong"(ST40) and "Zusanli"(ST36) for 30 min, once a day for 14 days. The body mass and abdominal circumference of rats were measured before and after treatment. The contents of serum follicle stimulating hormone (FSH), luteinizing hormone (LH) and estradiol (E2) were detected by ELISA. The number of corpus luteum and follicle were observed by HE staining. The expression levels of ER-β mRNA and protein in ovary were detected by fluorescence quantitative PCR and Western blot, respectively.
Results: Compared with the control group, the body mass and abdominal circumference, the contents of serum FSH and E2, and the expression levels of ER-β mRNA and protein in ovary were significantly increased (P<0.05)in the model group, while the number of mature follicles and corpus luteum increased significantly. Compared with the model group, the body mass and abdominal circumference, the contents of serum FSH and E2, and the expression levels of ER-β mRNA and protein in ovary were significantly decreased (P<0.05) in the acupuncture group, while the number of mature follicles and corpus luteum decreased significantly.
Conclusion: Electroacupuncture can effectively improve the levels of sex hormone and the development of ovary, down-regulate the expression levels of ER-β mRNA and protein in ovary, so as to regulate the process of sexual development of female adolescent obese rats induced by high-fat diet.
目的:观察电针对高脂饮食诱导的雌性生长期肥胖大鼠性发育水平和卵巢雌激素受体β(ER-β)表达的影响, 探讨电针治疗青少年肥胖的部分作用机制。方法:21日龄雌性SD大鼠随机分为对照组、模型组和针刺组, 每组6只。采用高脂饲料喂养6周建立肥胖大鼠模型。针刺组给予双侧“三阴交”“丰隆”“足三里”电针治疗, 连续波, 频率2 Hz, 强度0.5~1.2 mA, 30 min/d, 连续干预14 d。治疗前、后测量大鼠体质量和腹围;ELISA法检测大鼠血清卵泡刺激素(FSH)、黄体生成素(LH)、雌二醇(E2)含量;HE染色法观察大鼠卵巢黄体及卵泡数量;荧光定量PCR法检测大鼠卵巢ER-β mRNA的表达水平;Western blot法检测大鼠卵巢组织ER-β蛋白的表达水平。结果:与对照组比较, 模型组大鼠体质量、腹围明显升高(P<0.05), 血清FSH、E2含量和卵巢ER-β mRNA、蛋白的表达明显升高(P<0.05), 卵巢组织空卵泡及黄体数量明显增加;与模型组比较, 针刺组大鼠体质量、腹围明显降低(P<0.05), 血清FSH、E2含量及卵巢ER-β mRNA、蛋白的表达明显降低(P<0.05), 卵巢组织空卵泡数目及黄体数量降低, 可见不同发育阶段的卵泡。结论:电针可以改善高脂饮食诱导的雌性生长期肥胖大鼠的性激素水平, 改善卵巢组织发育, 调节卵巢ER-β mRNA及蛋白的表达水平, 从而调节雌性生长期肥胖大鼠性发育水平。.
Keywords: Electroacupuncture; Estrogen receptor β; Female rat; High-fat diet; Sexual development.