| Objective To observe the relationship between oxidative stress caused by NOX1 and NOX2 and cognitive impairment in aged chronic cerebral hypoperfusion(CCH)rats,and to discuss how electroacupuncture regulating NOX1 and NOX2 to ameliorate the aging CCH rats’ cognitive impairment and the possible mechanism of oxidative stress.Methods 60 healthy clean SD rats(18-20 months)who were selected to divide into the sham operation group(OS),model group(OM),electroacupuncture group(EA),perindopril group(PE)and candesartan group(C A)randomly.OS are only isolated carotid artery while the others were operated by ligation of bilateral carotid artery(2-VO)to copy CCH model.2 hours after the operation,began to cure rats: For EA rats,"Baihui" and "Dazhui" two points were treat with acupuncture needle(0.25mm×25mm)connecting Korean electric acupuncture apparatus for 30 minutes.PE and C A were treated via gavage with perindopril(0.5mg/kg/d)and candesartan(1mg/kg/d),the same conditions(grab the injection of physiological saline)treating to other groups at the same time.These steps were manipulated at a fixed time per day and lasted for 42 days.Observation index:(1)Laser Doppler flowmetry were used to record the region cerebral blood flow(r C BF)at these time points: 10 minutes before operation,10 minutes,1 weeks,2 weeks and 6 weeks after operation;(2)7 days before had been sacrificed,Morris water maze(MWM),which includes navigation experiment and space exploration,was used to experiment learning and memory ability of rats;and utilized open field(OF)test rats’ tension,self and inquiry ability in the new and abnormal environment;(3)After 42 days had passed,all groups were sacrificed.Western blotting(WB)used to record the expression of NOX2,NOX1,SOD1,SOD2 protein,while the level of ROS and MDA in hippocampus tested by enzyme linked immunosorbent assay(Elisa),the distribution of NOX1 and NOX2 in hippocampal CA1 region were observed by immunofluorescence.Results(1)the results of r CBF showed that: compared with OS,rats’ cerebral blood flow in OM,EA,PE and CA were decreased significantly(P<0.05 or P<0.01);r CBF of EA,PE and C A in 1,2 and 6 weeks were increased apparently compared to OM;while there was no marked difference ether EA,PE or C A(P>0.05).(2)About MWM,the positioning navigation experiment showed that the escape latency of OS,EA,PE and C A were obviously shortened than OM(P<0.05 or P<0.01),and there also were no statistically significant between EA,PE and C A(P>0.05).The results of location navigation experiments showed that compared with OM,the stay time of target quadrants in OS,EA,PE and CA was prolonged(P<0.05 or P<0.01),while no significant difference between EA,PE and CA(P>0.05).(3)The results of OP showed that compared with OS,the residence time in peripheral region of OM,EA,PE and CA was significantly shortened(P<0.01),although EA,PE and CA was longer than OM(P<0.01).(4)ELISA results showed that ROS in hippocampus of OM,EA,PE and CA were increased compared with OS,and the difference between OM and OS was significant(P<0.01),when no significant difference existed between EA,PE,CA and OS.But MDA in EA was higher than PE(P<0.05).(5)WB indicated NOX1 and NOX2 expression level increased,while SOD1 and SOD2 decreased in OM,EA,PE and CA(P<0.01);NOX1 and NOX2 were more in EA,PE and CA than OM(P<0.01),while SOD1 and SOD2 increased similarly(P<0.01).Compared with PE and CA,NOX1 and NOX2 in EA increased(P<0.01),while SOD1decreased(P<0.05 or P<0.01).About SOD2,EA had a higher level tha n CA(P<0.05).(6)The results of immunofluorescence made clear that NOX1 and NOX2 were positive in the CA1 region of hippocampal.Conclusion(1)Oxidative stress injury mediated by NOX1 and NOX2 may cause cognitive impairment in aging CCH rats;(2)Electroacupuncture may promote the cerebral blood flow,inhibit the activation of NOX1 and NOX2,reduce the products of oxidative stress,stimulate the levels of antioxidant enzymes,produce antioxidant effect,and reduce neuronal apoptosis to improve CCH rats’ cognitive dysfunction. |
PDF Full Text Request