PDE7抑制剂BRL-50481对小鼠酒精戒断引起的焦虑抑郁样行为的治疗作用及机制OA

OBJECTIVE To find out whether phosphodiesterase 7(PDE7)is involved in alcohol withdrawal-induced anxiety-and depression-like behaviors,and to investigate the therapeutic effects and mechanisms of PDE7 inhibitor BRL-50481 against these abnormal behaviors.METHODS ① Two month-old male C57BL/6J mice were divided into two groups:alcohol-naive control groups and alcohol-withdrawn groups.The alcohol-withdrawn groups were exposed to short-term(4 days)or long-term(14 days)alcohol vapor,followed by 7 or 14 days of withdrawal.During withdrawal,the sucrose preference test(SPT),forced swimming test(FST),tail suspension test(TST)and elevated plus maze test(EPMT)were conducted to evaluate the modeling protocol.Western blotting was performed to detect the protein expression levels of PDE7 in the amygdala.Blood samples were collected from mice 7 and 14 days into alcohol vapor exposure to measure serum alcohol levels.② Mice were randomly divided into the control group,model group,and model+PDE7 inhibitor BRL-50481 treatment group.The control group was housed normally without treatment while the other groups were exposed to alcohol vapor for 14 days,followed by 14 days of withdrawal.Starting from the first day of withdrawal,mice received the PDE7 inhibitor BRL-50481 at 0.2,1.0,or 5.0 mg·kg-1,or saline.Depression-and anxiety-like behaviors were assessed using the SPT starting on the tenth day of withdrawal,the FST and TST on the thir-teenth day of withdrawal,and the EPMT on the fourteenth day of withdrawal.After completing the behavioral tests,mice were euthanized,and amygdala tissues were collected.ELISA was performed to detect the expression levels of cyclic adenosine monophosphate(cAMP)while Western blotting was used to detect the protein expression levels of the exchange protein directly activated by cAMP(EPAC),brain-derived neurotrophic factor(BDNF),and phosphorylation of cAMP response element-binding protein(p-CREB)in the amygdala.RESULTS ① Alcohol vapor exposure kept serum alcohol levels stable in mice.Compared with the control group,the alcohol-withdrawn group exposed to short-term(4 days)alcohol vapor did not show typical depression-and anxiety-like behaviors.Compared with the control group,the alcohol-withdrawn group exposed to long-term(14 days)alcohol vapor showed typical depression-and anxiety-like behaviors,as evidenced by a significant decrease in sucrose preference in the SPT,a significant increase in immobility time in the FST and TST,and a significant decrease in the percentage of entries and time spent in the open arms in the EPMT.Addi-tionally,PDE7A expression levels in the amygdala were significantly increased.② Compared with the control group,the depression-and anxiety-like behaviors were significantly ameliorated in the model+BRL-50481 5.0 mg·kg-1 group in that there was a significant increase in sucrose preference in the SPT,a significant decrease in immobility time in the FST and TST and a significant increase in the percentage of entries and time spent in the open arms in the EPMT.Additionally,PDE7A expression levels in the amygdala were significantly decreased in the model+BRL-50481 1.0 mg·kg-1 group.Com-pared with the control group,the levels of cAMP,EPAC2,BDNF and p-CREB in the amygdala were significantly decreased in the model group.Compared with the model group,the levels of cAMP and EPAC2 in the amygdala were significantly increased in the model+BRL-50481 1.0,5.0 mg·kg-1 groups,the levels of p-CREB in the amygdala were significantly increased in the model+BRL-50481 0.2,1.0 and 5.0 mg·kg-1 groups,and the levels of BDNF in the amygdala were significantly increased in the model+BRL-50481 1.0 mg·kg-1 groups.CONCLUSION Alcohol withdrawal-induced anxiety-and depression-like behaviors can be ameliorated by the PDE7 inhibitor BRL-50481,and the mechanism may be associated with the inhibition of PDE7A and the activation of its downstream cAMP EPAC2 CREB BDNF signaling pathway in the amygdala.