Diazoxide Mediated Deep Low Temperature And Low Flow Model In Mice Brain Protection Research

PartEffect of diazoxide with different concentrations on braintissue in mice undergoing deep hypothermic low flow.Objective To observe the influence of diazoxide with different concentrations onbrain tissue in mice model of deep hypothermic low flow.Methods The C57BL/6mice (n=240) were randomly and equitably divided into8groups: sham group,model group,diazoxide group (2,5,10mg/kg)andwortmannin+diazoxide (2,5,10mg/kg).Operation group was cerebralischemia-reperfusion(I-R) that bilateral common carotid arteries were occluded for120min at (18.510.5)℃and then reperfused and rewarmed afterwards,while thesham operation group excluded the occlusion.The protein expressions of akt,p-akt1were determined by Western blot at2h,24h and72h after I/R,respectively.Five micetaken from each group at reperfusion2h,24h and72h timepoint respectively wererandomly decapitated and the coronal brain slices were stained withtriphenyltetrazolium chloride(TTC) solution The samples were postfixed and takenpicturesResults The diazoxide group had the characteristic changes of I/R injury.The proteinexpress of p-akt1expression were higher in diazoxide group than those subgroups at24and72hours after reperfusion(P<0.05).The expression of p-akt1were increased at24and72hours after reperfusion in diazoxide(2mg/kg) group than that in thosediazoxide groups(P<0.05). The diazoxide group had less pathological injury thanthose groups at24and72hours after reperfusion(P<0.05).The pathological injurywere decreased at24and72hours after reperfusion in diazoxide(2mg/kg) group than that in those diazoxide groups(P<0.05).Conclusion These results suggested that the neuroprotective effects of diazoxideagainst cerebral I/R injury during deep hypothermia low flow in mice.PI3K/Aktsignal pathway has cerebral protective in mice model undergoing deep hypothermialow flow by increased the expression of p-akt1. PartThe protective effect and mechanism of diazoxide on braintissue underging deep hypothermic low flow model in mice.AbstractObjective To investigate the protective effect and mechanism of diazoxide on braintissue underging deep hypothermic low flow model in mice.Methods The C57BL/6mice(n=270) of3weeks were divided into wild type (wt)group, the akt1gene knockout group, akt2gene knockout group, each group weredivided into control group (sham), model group (model) and the diazoxide group(diazoxide, dz), each group30. Operation group was cerebralischemia-reperfusion(I-R) that bilateral common carotid arteries were occluded for120min at (18.510.5)℃and then reperfused and rewarmed afterwards,while thesham operation group excluded the occlusion. The protein expressions of akt銓akt1銓akt3銓p-akt1銓p-gsk-3βwere determined by Western blot at2h,24h and72h afterI/R,respectively.The mRNA expressions of akt1銓akt2銓akt3were determined by RealTime PCR at2h,24h and72h after I/R,respectively.Five mice taken from eachgroup at reperfusion2h,24h and72h timepoint respectively were randomlydecapitated and the coronal brain slices were stained with triphenyltetrazoliumchloride(TTC) solution The samples were postfixed and taken picturesResult The p-akt1, p-GSK-3beta protein expression in akt1gene knockout groupis lower than the wt group and akt2gene knockout(p <0.05), while the akt2geneknockout group compared with the wt group, there was no statistically significantdifference (p>0.05), dz group is higher than the model group, model group washigher than sham group each genotype (p <0.05). The akt1gene knockout groupcompared with the akt2gene knockout group and wt group, brain damage is aggravating(p <0.05), akt2gene knockout compared with wt group, there was nostatistically significant difference at24and72hours after reperfusion(P<0.05)(p>0.05).The expression of Akt1mRNA and Akt3mRNA in the model group was higherthan sham group, dz group is higher than the model group in different genotypes at2,24and72hours after reperfusion(P<0.05).Conclusion Diazoxide has brain protective effects in mice model undergoing deephypothermic low flow, its function mechanism may be through the activation ofPI3K/Akt signaling pathways, activate the akt1protein, thus regulating GlycogenSynthesis Kinase-3beta. Diazoxide could make Akt1mRNA and Akt3mRNAexpression increased, further regulate p-Akt1and p-GSK-3beta proteinexpression increased.