The Cognitive Function And Expression Of Hydrogen Sulfide At Different Pfases In Diabetic Model Mice

ObjectiveTo observe the changes of Cystathionine-β-synthase(CBS) andhydrogen sulfide(H2S) in brain tissues and cognitive function at differentphases in diabetic model mice.MethodsForty C57BL/6J mice were divided into normal group and model group.Mouse models of diabetes mellitus were established by high fat diet withmedium dose streptozocin(STZ). After the successful establishment of themodel, HFD feeding was continued for an additional4,8,12,16weeks.Mouse models were subdivided into4groups according to different phases.Changes of recognition were tested by Morris water maze. The gas levels ofH2S, activity of CBS and protein expression were detected byimmunohistochemistry and sensitive sulphur electrode, and correlationanalysis was conducted.ResultsCompared with normal group, the latency of memory of mouse modelsstarted increasing at4weeks (P<0.05), while the percentage of total time left in the target quadrant began decreasing at8weeks (P<0.01). The gas levelsof H2S, activity of CBS and protein expression in the cortex weresignificantly lower than that in each normal group at12and16weeks(P<0.05). The gas levels of H2S, activity of CBS and protein expression inthe hippocampus were significantly decreased at8,12and16weeks,compared with each normal group (P<0.01). It was revealed by correlationanalysis that the gas levels of H2S, activity of CBS were positively correlatedwith cognitive function.ConclusionThe gas levels of H2S, activity of CBS and protein expression aredecreased in diabetic mice, and the cognitive function declined. Reductionof endogenous H2S and CBS activity may initiate or exacerbate DMcognitive impairment.