针药结合对抑郁症大鼠脑-肠轴功能的影响

Effect of acupuncture plus medication on the brain-gut axis function in depressed rats

摘要:

目的： 观察针药结合治疗对抑郁症大鼠行为学、肠道菌群及5-羟色胺（5-hydroxytryptamine，5-HT）、5-羟色氨酸（5-hydroxytryptophan，5-HTP）分子表达的影响，探讨针药结合治疗抑郁症的可能机制。方法： 将35只雄性SD大鼠随机分成空白组、模型组、电针组、氟西汀组和针药结合组，每组7只。经慢性不可预知温和刺激（chronic unpredictable mild stress，CUMS）制备抑郁症大鼠模型。电针组和针药结合组大鼠选取“腰阳关”及双侧“天枢”“足三里”“大肠俞”穴电针干预，每次30 min，1次/d，连续21 d。氟西汀组、针药结合组用0.2%氟西汀按10 mg/kg灌胃治疗，1次/d，连续21 d。蔗糖偏好实验（sucrose preference test，SPT）、旷场实验（open field test，OFT）和强迫游泳实验（forced swimming test，FST）分析大鼠行为学变化，16S rDNA高通量测序法检测肠道菌群结构多样性，ELISA法检测海马、结肠和血清中5-HT、结肠和血清中5-HTP含量。结果： 与空白组相比，模型组大鼠SPT糖水消耗量和OFT总距离减少，FST不动时间增加，海马中5-HT以及结肠组织和血清中5-HT、5-HTP含量减少（P<0.01），肠道有益菌群种类和相对丰度减少；与模型组相比，各干预组大鼠的SPT糖水消耗量增加，OFT总距离增加，FST不动时间减少，海马中5-HT及血清中5-HT和5-HTP含量增加（P<0.01，P<0.05），肠道有益菌群种类和相对丰度增加；与氟西汀组比较，针药结合组FST不动时间减少，大鼠海马、血清组织中5-HT含量增加（P<0.05），有益菌群升高趋势更明显，有害菌群降低趋势更明显。结论： 针药结合治疗能明显改善CUMS大鼠抑郁样行为，其作用机制可能与提高肠道有益菌群的种类和相对丰度，上调脑-肠轴5-HT、5-HTP等相关分子表达有关。

Abstract:

Objective: To observe the effects of acupuncture plus medication therapy on behavior, intestinal flora, and the expression of 5-hydroxytryptamine (5-HT) and 5-hydroxytryptophan (5-HTP) in depressed rats, and to explore the possible mechanism of acupuncture plus medication in the treatment of depression. Methods: Thirty-five male SD rats were randomly divided into a blank group, a model group, an electroacupuncture (EA) group, a fluoxetine group, and an acupuncture plus medication group, with 7 rats in each group. The depressed rat model was prepared by exposing to chronic unpredictable mild stress (CUMS). In the EA group and the acupuncture plus medication group, the rats were intervened by EA at "Yaoyangguan" , bilateral "Tianshu" , "Zusanli" , and "Changshu" , 30 minutes each time, once a day for 21 days. In the fluoxetine group and the acupuncture plus medication group, the rats received intragastric administration with 0.2% fluoxetine at 10 mg/kg, once a day for 21 days. The sucrose preference test (SPT) , open field test (OFT) , and forced swimming test (FST) were performed to analyze the behavioral changes of rats. The diversity of intestinal flora was detected by 16S rDNA high-throughput sequencing. The levels of 5-HT in hippocampus, colon, and serum, and 5-HTP in colon and serum were detected by enzyme-linked immunosorbent assay (ELISA). Results: Compared with the blank group, in the model group, the sugar water consumption of SPT and the total distance of OPT were significantly decreased, the immobility time of FST was significantly increased, the levels of 5-HT in hippocampus, 5-HT and 5-HTP in colon tissue and serum were significantly decreased (P<0.01) , and the species and relative abundance of intestinal beneficial flora were decreased. Compared with the model group, in each intervention groups, the sugar water consumption of SPT and the total distance of OPT were significantly increased, the immobility time of FST was significantly decreased, the levels of 5-HT in hippocampus, 5-HT and 5-HTP in colon tissue and serum were increased (P<0.01, P<0.05) , and the species and relative abundance of intestinal beneficial flora were increased. Compared with the fluoxetine group, in the acupuncture plus medication, the immobility time of FST was decreased, the levels of 5-HT in hippocampus and serum were increased (P<0.05) , and the increasing trend of beneficial flora and the decreasing trend of harmful flora was more obvious. Conclusion: Acupuncture plus fluoxetine therapy could significantly alleviate the depression-like behavior in CUMS rats. And its mechanism may be related to the increasing the species and relative abundance of intestinal beneficial flora and up-regulating the expression of brain-gut axis 5-HT, 5-HTP and other related molecules.