菟丝子总黄酮对来曲唑致多囊卵巢综合征大鼠模型的影响

目的:探讨菟丝子总黄酮对来曲唑致大鼠多囊卵巢综合征(PCOS)模型的影响。方法:正常组除外,其余大鼠每天灌服来曲唑1 mg·kg~(-1)复制PCOS动物模型,连续21 d。造模第16天,阴道涂片检测动物周期,以阴道上皮细胞持续角化者为PCOS成模大鼠,并随机分为模型组、达英-35组(0. 339 2 mg·kg~(-1))和菟丝子总黄酮高、中、低剂量组(200,100,50 mg·kg~(-1))。依据组别给予相应药物,连续21 d。给药结束后,取材,计算卵巢指数;酶联免疫吸附测定(ELISA)检测血清雌激素(E_2),睾酮(T),促性腺激素释放激素(GnRH),卵泡刺激素(FSH)和促黄体生成素(LH)水平;取大鼠右侧卵巢,苏木素-伊红(HE)染色光镜观察病理改变;免疫组化法检测下丘脑、垂体、左侧卵巢雄激素受体(AR)表达。结果:与正常组比较,模型组大鼠血清T,GnRH,LH水平显著升高,卵巢指数和LH/FSH值显著升高,FSH和E_2水平显著降低(P 0. 05,P 0. 01),卵巢组织闭锁卵泡增多、卵泡膜细胞层增厚明显,下丘脑、垂体和卵巢组织AR表达显著升高(P 0. 01)。与模型组比较,菟丝子总黄酮高、中、低剂量组可显著降低PCOS模型大鼠血清T,GnRH和LH水平,降低卵巢指数和LH/FSH值(P 0. 01);菟丝子总黄酮高、中剂量组可显著升高PCOS模型大鼠血清E_2水平(P 0. 01),明显升高FSH水平(P 0. 05),菟丝子总黄酮低剂量组可明显升高PCOS模型大鼠血清E_2水平(P 0. 05)。菟丝子总黄酮高、中、低剂量组可不同程度改善PCOS模型大鼠卵巢组织皮质增厚胶原化、闭锁卵泡增多、黄体减少等病理改变。免疫组化结果表明,菟丝子总黄酮高、中、低剂量组可显著降低下丘脑、垂体和卵巢AR表达(P 0. 01)。结论:菟丝子总黄酮可能通过调节雌雄激素分泌、影响下丘脑-垂体-卵巢轴途径发挥对PCOS模型大鼠的保护作用。

Effect of Dodder Total Flavone on Polycystic Ovary Syndrome Rat Models Induced by Letrozole

Objective: To investigate the effect of dodder total flavone on polycystic ovary syndrome (PCOS) rat models induced by letrozole. Method: Except the blank group, the other rats were given letrozole 1 mg·kg^-1 for 21 consecutive days to replicate PCOS animal model. On the 16^th day of the modeling, the estrous cycle was detected by vaginal smear, and rat with persistent keratinization of vaginal epithelial cells were selected as the PCOS model rat. The model rats were randomly divided into model group, Dacin-35 group, and high, middle, low-dose dodder total flavonoids groups. The corresponding drugs were given for 21 consecutive days. At the end of the administration, materials were collected to calculate ovary index, and enzyme-linked immunosorbent assay(ELISA) was used to measure estrogen (E₂), testosterone (T), gonadotropin-releasing hormone (GnRH), follicle stimulating hormone (FSH) and luteinizing hormone (LH) levels of serum. The right ovary of rats was stained with haematoxylin-eosin (HE), and the pathological changes were observed by optical microscope. Androgen receptor(AR) expressions in hypothalamus, pituitary and ovary were detected by mmunohistochemistry. Result: Compared with the blank group, serum T, GnRH and LH levels, ovarian index and LH/FSH ratio were significantly increased, while FSH and E₂ levels were significantly decreased (P<0.05,P<0.01). Ovarian tissue follicular atresia increased, and the cell layers of follicular membrane were thickened significantly. AR expressions in hypothalamus, pituitary and ovarian tissues were significantly increased in the model group (P<0.01). Compared with the model group, serum E₂, T, GnRH and LH levels, ovarian index and LH/FSH ratio were significantly decreased in high, middle and low-dose dodder total flavonoids groups (P<0.01); Serum E₂ level was significantly increased (P<0.01), and FSH level was obviously increased (P<0.05) in high and middle-dose dodder total flavonoids group. Serum E₂ level in PCOS model rats was obviously increased in low-dose dodder total flavonoids group (P<0.05). The pathological changes of ovarian tissue of cortical thickening and collagenization, atresia follicle increase and corpus luteum decrease of PCOS model rats were alleviated to different degrees in high, middle and low-dose dodder total flavonoids groups. Immunohistochemical results showed that high, middle and low-dose dodder total flavonoids groups could significantly reduce AR expressions in hypothalamus, pituitary and ovary (P<0.01). Conclusion: Dodder total flavonoids may play a protective role in PCOS model rats by regulating the secretion of estrogen and androgen and affecting the hypothalamic-pituitary-ovary axis pathway.