腧穴“解郁方”对慢性不可预测轻度应激抑郁大鼠下丘脑-垂体-肾上腺轴及BDNF/TrkB/CREB通路的影响

Effects of Acupuncture"Jieyu Formula"on Hypothalamic-pituitary-adrenal Axis and BDNF/TrkB/CREB Pathway in Rats with Chronic and Unpredictable Mild Stress-induced Depression

目的:观察腧穴“解郁方”对慢性不可预测轻度应激(CUMS)抑郁大鼠下丘脑-垂体-肾上腺(HPA)轴和脑源性神经营养因子(BDNF)/酪氨酸激酶B受体(TrkB)/环磷酸腺苷反应元件结合蛋白(CREB)信号通路的影响。方法:40只无特定病原体(SPF)级Sprague Danley(SD)雄性大鼠随机分为空白组(10只)、模型组(10只)、西药组(10只)、针刺组(10只),除空白组外,其余3组连续28 d构建CUMS抑郁大鼠模型,造模成功后,西药组连续14 d灌胃盐酸帕罗西汀混悬液,每日1次;针刺组针刺百会、太冲、神门,每日1次,每次20 min,连续针刺14 d。苏木素-伊红(HE)染色观察大鼠海马病理变化,酶联免疫吸附法(ELISA)测定血清促肾上腺皮质激素释放激素(CRH)、促肾上腺皮质激素(ACTH)、皮质醇(CORT)水平;免疫组化(IHC)检测海马BDNF、TrkB表达情况,蛋白质免疫印迹法(Western Blot)及实时荧光定量-聚合酶链式反应(PCR)测定海马BDNF、TrkB、CREB蛋白及mRNA的表达。结果:与空白组比较,模型组血清CRH、ACTH和CORT含量上升(P<0.01),海马病理损伤严重,海马BDNF、TrkB平均光密度降低(P<0.01),BDNF、TrkB、CREB蛋白及mRNA明显下降(P<0.05或P<0.01)。与模型组比较,针刺组血清CRH、ACTH、CORT含量下降(P<0.05),海马病理损害明显减轻,BDNF、TrkB平均光密度明显增加(P<0.05),BDNF、CREB、TrkB蛋白及mRNA表达水平上升(P<0.05)。结论:腧穴“解郁方”可能通过调节HPA轴和调控BDNF/TrkB/CREB信号通路,改善CUMS诱导的大鼠抑郁样行为。

Objective:To observe the effects of"Jiyu Formula"on the hypothalamic-pituitary-adrenal(HPA)axis and brain-derived neurotrophic factor(BDNF)/tyrosine kinase B receptor(TrkB)/cyclic adenosine phosphate reaction element binding protein(CREB)signaling pathway on chronic and unpredictable mild stress(CUMS)depressed rats.Methods:Forty specific pathogen free(SPF)grade SD male rats were randomly divided into blank group(10 rats),model group(10 rats),western medicine group(10 rats),and acupuncture group(10 rats).Except for the blank group,the other three groups were continuously used to construct a depression rat model by CUMS for 28 days.After successful modeling,the western medicine group was gavaged Paxil hydrochloride suspension once a day for 14 days.In the acupuncture group,Baihui,Taichong and Shenmen were acupunctured once a day for 20 minutes each time for 14 days.The pathological changes of hippocampus were detected by hematoxylin-eosin(HE)staining,and the levels of serum adrenocorticotropin releasing hormone(CRH),adrenocorticotropin(ACTH)and cortisol(CORT)were detected by enzyme-linked immunosorbent assay(ELISA).The expressions of BDNF and TrkB in hippocampus were detected by immunohistochemistry(IHC),and the expressions of BDNF,TrkB and CREB protein and mRNA in hippocampus were detected by Western Blot and real-time fluorescence quantification and polymerase chain reaction(PCR).Results:Compared with blank group,the contents of serum CRH,ACTH and CORT in the model group significantly increased(P<0.01),the hippocampal pathological injury was serious,the average optical density of BDNF and TrkB in hippocampus significantly decreased(P<0.01).The protein and mRNA levels of BDNF,TrkB,and CREB were significantly decreased(P<0.05 or P<0.01).Compared with model group,the contents of serum CRH,ACTH and CORT in the acupuncture group significantly decreased(P<0.05),the hippocampal pathological injury was significantly alleviated,the average optical density of BDNF and TrkB significantly increased(P<0.05)The protein and mRNA levels of BDNF,TrkB,and CREB were significantly increased(P<0.05).Conclusion:Acupuncture"Jieyu Formula"could improve depression-like behavior induced by CUMS in rats by regulating HPA axis and BDNF/TrkB/CREB signaling pathway.