Effect Of Moxibustion On Anxiety/Depression Like Emotion And Microglia In Striatum Of UC Mice

Background and ObjectivePrevious studies showed that the moxibustion had considerable treatment effects on ulcerative colitis(UC)via anti-inflammatory function.It is suggested that moxibustion may be effective on the mood disorders related to UC.This study aims to clarify whether moxibustion could alleviate anxiety / depression like emotion in UC mice,and to explore potential effects on the activity of striatal microglia,and to find out the possible mechanism of Moxibustion in the treatment of anxiety / depression like emotion via experiment in UC-modeling mice.MethodsUC-modeling mice were established by drinking 2% dextran sulfate sodium(DSS)in Male C57 BL / 6J mice.After successful modeling,the mice were randomly divided into model group and moxibustion group(8 mice/group).The same number of mice were set as control group.The moxibustion started at the fifth day after modeling,"Guanyuan","Zusanli" and "Baihui" acupoints were selected for treatment about 15 minutes per day.The moxibustion stopped on the 9th days.The control and model groups were bound but not treated.The general condition,fecal occult blood,weight change,disease activity index(DAI)of mice in each group were observed and compared.The morphological changes of colon were observed by pathological section,and the effects of moxibustion was evaluated.Elevated plus maze(EPM),open field test(OFT),sugar preference test(SPT)and tail suspension test(TST)were used to observe the changes of anxiety / depression like emotion and behavior in each group,and to evaluate the related effects of moxibustion on alleviating adverse emotions,and the correlation analysis of DAI and behavioral indicators was carried out.Western blot(WB)was used to estimate the expression of IBA1(microglia activity marker)in striatum of mice,and to explore whether moxibustion can improve anxiety /depression like behavior in UC mice.Results1.Moxibustion can improve intestinal inflammation and anxiety / depression like emotion in UC mice:1.1 Effect of moxibustion on intestinal inflammation in UC miceAfter modeling,the general condition of mice in the model group became worse,the color of hair became dark,the feces were bloody or purulent,the weight decreased significantly(P < 0.001),DAI score increased significantly(P < 0.001),there were ulcerative surface,necrotic focus,destruction of gland structure,infiltration of inflammatory cells and tissue proliferation in intestinal mucosa;After moxibustion treatment,the general condition of UC mice was improved,fecal occult blood basically returned to normal,DAI score was significantly lower than that of the model group(P < 0.001),intestinal ulcer focus was significantly reduced,inflammatory cell infiltration and tissue proliferation were improved.Combined with our previous experimental studies,moxibustion can significantly improve the intestinal inflammation of UC mice.1.2 Effect of moxibustion on anxiety / depression like behavior in UC miceThe elevated cross maze test showed that compared with the control group,the percentage of the time and times of entering the open arm(OT% and OE%)in the total time and times of entering the arm in the model group were significantly decreased(P<0.001);Compared with the model group,the OT% of moxibustion group increased(P < 0.01),and OE% values increased(P < 0.05).The results of open field experiment showed that compared with the congrol group,the time ratio(CT%)of mice entering the central area in the model group decreased(P < 0.05),and the time ratio(CT%)of mice entering the central area after moxibustion treatment did not change significantly,and there was no statistical difference between the model group and the model group(P > 0.05).Compared with the control group,the sugar preference index of the model group did not change significantly(P > 0.05).After moxibustion treatment,the sugar preference index of the model group was slightly higher than that of the model group,but the difference was not statistically significant(P > 0.05).The tail suspension experiment showed that compared with the control group,the cumulative immobility time of the model group was significantly increased(P < 0.001),and the cumulative immobility time of the mice after moxibustion treatment was reduced(P < 0.05).Meanwhile,the results of correlation analysis between DAI and behavioral indicators showed that DAI was moderately negatively correlated with EPM-OT%(r =-0.67,P < 0.001),moderately negatively correlated with EPM-OE%(r =-0.65,P < 0.001),slightly negatively correlated with OFT-CT%(r =-0.41,P < 0.05),and moderately positively correlated with TST(r = 0.68,P < 0.001).2.Effect of moxibustion on the expression of Iba1 in striatum of UC miceWB was used to estimate the expression of Iba1 in striatum of UC mice.The results showed that compared with the control group,the content of Iba1 in striatum of model group was increased(P < 0.05);After moxibustion treatment,the content of Iba1 in striatum of mice was lower than that of model group(P < 0.05).Conclusion1.Moxibustion could alleviate the anxiety / depression like emotion of UC mice to some degree.2.Moxibustion alleviates anxiety / depression like emotion in UC mice may be related to its regulation effects on the activity of microglia in striatum.