针刺对慢性束缚应激抑郁模型大鼠海马凋亡相关因子的影响

Acupuncture improved depressive behavior by regulating expression of hippocampal apoptosisrelated factors in psychological stress-induced depression rats

目的:观察针刺对抑郁模型大鼠海马细胞色素C、半胱氨酸天冬氨酸蛋白酶-3(caspase-3)、凋亡诱导因子(AIF)表达的影响,从凋亡途径探讨针刺防治心理应激引起的早期抑郁的机制。方法:SD大鼠随机分成空白组、模型组、针刺组、氟西汀组,每组8只。应用慢性束缚结合孤养方法建立慢性心理应激抑郁大鼠模型。针刺组于每日应激前1h针刺“百会”“印堂”和双侧“三阴交”,每日1次,每次20min,持续28d;氟西汀组于每日应激前1h用盐酸氟西汀混悬液(1mL/100g,0.18mg/mL)灌胃,每日1次,持续28d。以体质量和糖水偏好实验、旷场实验评价抑郁模型大鼠行为学改变情况;用Western blot法检测大鼠海马组织细胞色素C、caspase-3和AIF的蛋白表达水平;用DCFH-DA荧光探针技术检测大鼠海马组织活性氧(ROS)的含量。结果:实验结束后,模型组大鼠体质量、糖水偏好指数、旷场实验水平穿越格数和垂直竖立次数均低于空白组(P<0.01)。与模型组比较,针刺组和氟西汀组大鼠体质量、糖水偏好指数上升,水平穿越格数和垂直竖立次数增加(P<0.01,P<0.05)。与空白组比较,模型组大鼠海马组织ROS、细胞色素C、caspase-3和AIF的表达水平显著升高(P<0.01)。与模型组比较,针刺组和氟西汀组大鼠海马组织ROS、细胞色素C、caspase-3和AIF水平显著降低(P<0.01)。结论:针刺干预能显著降低抑郁模型大鼠海马组织凋亡途径的关键因子细胞色素C、caspase-3和AIF的蛋白表达水平,其机制可能与下调线粒体ROS含量有关,这可能是针刺发挥抗抑郁效应的重要途径之一。

Objective To investigate the effect of acupuncture on behavior changes and the expression of reactive oxygen species(ROS),cytochrome C,cysteine-containing aspartate-specific proteases-3(caspase-3),apoptosis inducing factor(AIF)in the hippocampus of rats exposed to chronic restraint stress(CRS),so as to provide experimental evidence for the prevention and treatment of depression.Methods Thirty two male SD rats were equally randomized into control,model,acupuncture and medication(Fluoxetine)groups according to the random number table.The depression model was established by chronic psychological stress stimulation(fasting,water deprivation,chronic restraint combined with solitary raising for 28 days).Manual acupuncture stimulation(2 circles/s)was applied to"Baihui"(GV20),"Yintang"(GV29)and bilateral"Sanyinjiao"(SP6)for2 min,followed by retaining the needles for 20 min.Rats in the medication group were treated by gavage of Fluoxetine(0.18 mg/mL,1 mL/100 g body weight).The treatment was conducted once daily for 28 days.The depression-like behavior was evaluated by using open-field test,sucrose preference test,and body weight.The content of ROS of the right hippocampus tissue was detected by using dichloro-dihydro-fluorescein diacetate(DCFH-DA)assay,and the expression levels of cytochrome C,caspase-3 and AIF proteins of hippocampus were determined by using Western blot.Results After 28 days’ stress procedure,the depression rats in the model group showed a significant decrease in the numbers of crossing and rearing of open-field test,sucrose preference index and the body weight compared to the control group(P<0.01).The content of ROS and expression levels of cytochrome C,caspase-3 and AIF in the hippocampus of the model group were significantly increased relevant to the control group(all P<0.01).After the intervention and compared with the model group,the decreased levels of the numbers of crossing and rearing,body weight and sucrose preference index,and the up-regulated levels of content of ROS and expression of cytochrome C,caspase-3 and AIF proteins were all reversed in both acupuncture and medication groups(P<0.01,P<0.05),displaying an anti-depressant effect.The effect of acupuncture was significantly superior to that of medication in up-regulating the numbers of crossing and rearing(P<0.01,P<0.05),and in down-regulating the expression of caspase-3(P<0.01).No significant differences were found between the medication and acupuncture groups in increasing the body weight and sucrose preference index,and in down-regulating the expression of cytochrome C and AIF proteins(P>0.05).Conclusion Acupuncture intervention can significantly reduce ROS content and expression level of cytochrome C,caspase-3 and AIF proteins in the hippocampus possibly by inhibiting the chronic psychological stress-hippocampal oxidative stress-mitochondrial apoptotic pathway in psychological stress-induced depression rats,which may contribute to its effect in relieving depression.