白藜芦醇对围绝经期抑郁症模型小鼠行为学影响及机制分析

Behavioral Effect and Mechanisms of Resveratrol on Perimenopausal Depression Model in Mice

摘要:

目的：探讨白藜芦醇（RSV）对围绝经期抑郁症模型小鼠行为学影响，并观察其作用机制。方法：清洁级昆明种小鼠随机分为假手术组，围绝经期抑郁症模型组，氟西汀组（3 mg·kg^-1），白藜芦醇低、中、高剂量组（10，20，40 mg·kg^-1），每组10只。采用小鼠双侧卵巢切除（OVX）联合慢性不可预知性温和应激（CUMS）法制备围绝经期抑郁症动物模型。给药组于每日应激前1 h灌胃给药，其余各组给予等体积生理盐水，共计21 d。观察小鼠一般体征，行阴道上皮角化实验检测动情周期变化，采用旷场实验（OFT），强迫游泳实验（FST）及体重测试（BWM）观察行为学变化，尼氏染色观察海马组织神经元形态学变化，酶联免疫吸附法（ELISA）检测脑组织单胺类递质5羟色胺（5-HT），去甲肾上腺素（NE）及多巴胺（DA）含量变化，免疫组织化学法（IHC）检测海马组织雌激素受体α（ER_α），ER_β免疫反应阳性区域蛋白表达。结果：与假手术组比较，阴道上皮角化实验显示，各OVX组小鼠连续7 d内检测未见动情周期变化，证明去势成功；行为学显示，围绝经期抑郁症模型组小鼠有抑郁样行为，表现为体重增加缓慢，OFT自发活动及探索行为减少，FST行为绝望时间增加（P<0.01）；尼氏染色显示海马区神经元损伤、萎缩及丢失，尼氏小体数量减少；ELISA法显示脑组织单胺类递质5-HT，NE及DA含量减少（P<0.01）；IHC法显示海马组织CA3区ER_α及ER_β，DG区ER_β免疫蛋白反应阳性区域积分吸光度IA值减少（P<0.01）。与模型组比较，给予不同剂量白藜芦醇治疗后，均可改善围绝经期抑郁症模型小鼠行为学异常，表现为体重增加迅速，OFT自发活动及探索行为增加，FST行为绝望时间减少（P<0.01）；脑组织5-HT，NE，DA含量增加（P<0.01）；海马组织CA3区ER_α及ER_β，DG区ER_β免疫反应蛋白阳性区域IA值（P<0.01）增加；各剂量组间比较，以中剂量较为明显（P<0.05）。结论：补充植物雌激素白藜芦醇可改善围绝经期抑郁症模型小鼠抑郁样行为，其机制与抑制海马神经元损伤、上调脑组织单胺类递质5-HT，NE，DA含量及增加海马组织CA3区ER_α，CA3及DG区ER_β表达有关。

Abstract:

Objective: To discuss the effects and mechanisms of resveratrol on perimenopausal depression model in mice. Method: Clean-grade Kunming mice were randomly divided into the sham group, the model group, the fluovetine group (3 mg·kg^-1) and resveratrol groups (10, 20, 40 mg·kg^-1), with 10 mice in each group. The mice were gavaged one hour before the daily stress, while the others were gavaged with physiological saline for consecutively 21 days. The perimenopausal depression model in mice was established by Ovariectomy and chronic unpredictable mild stress (CUMS). The general physical signs of the mice were observed, and experience of vaginal epithelial cells was conducted to detect changes in estrus cycle. The depressed behavior of mice was observed by body weight measurement (BWM), open field test (OFT) and foece swimming test (FST). Changes in 5-HT, NE and DA contents in mice brain were detected by ELISA methods. ER_α and ER_β protein expressions in hippocampus were detected by IHC method. Result: Compared with the sham group, the mice in OVX group did not show any change in estrous cycle for seven continuous days, indicating the successful modeling. The mice in model group appeared the behavior of depression, their body weight mice were decreased, the scores of horizontal and vertical motion in OFT were decreased, and the behavioral despair time were extended (P<0.01). Nissl's staining showed hippocampus neuron damage, atrophy and loss, and decrease in the number of Nissl bodies. The results of ELISA test showed that the content of 5-HT, NE and DA in brain tissues were decreased (P<0.01); IHC showed that the protein expressions of ER_α and ER_β in hippocampus CA3 area were decreased, and IA of ER_β in DG area were decreased. Compared with the model group, after administration with different doses of resveratrol, all of mice in the perimenopausal depression model showed relieve in the abnormalities of behavior, which were characterized by rapid body mass increase, increase in spontaneous activities and exploratory behavior of OFT, reduction in the behavioral despair time of FST (P<0.01), increase in the content of the brain tissue 5-HT, NE and DA (P<0.01), and rise in ER_α and ER_β in hippocampus CA3 area and IA of ER_β in DG area (P<0.01). Among each dose group, the medium-dose group was more obvious (P<0.05). Conclusion: Phytoestrogens resveratrol can alleviate perimenopausal depression in mice depressive behavior. Its mechanism is correlated with inhibition in neurons injury, up-regulation in the content of monoamine neurotransmitters 5-HT, NE and DA in brain tissues, and increase in the expression in ER_α and ER_βin hippocampus CA3 area and IA of ER_βin DG area.