Roles Of CYP1B1 Knockout In Cognitive Impairment Mice With Type 2 Diabetes

PART1:the low dose of streptozotocin combined with high fat and high sugar diet induced the formation of type 2 diabetic miceObjective:CYP1B1(cytochrome P450,family 1,subfamily B,polypeptide 1)knockout mice(KO)were associated with wild-type mice(WT)in high fat and high sucrose diet(HFSD)Low-dose streptozotocin(STZ)in the case of type 2 diabetes mellitus.Methods:20-22 g wild type(WT)and CYP1B1 knockout type(KO)male mice were randomly divided into high fat and high sucrose diet(HFSD)and normal diet group(Normal Chew,NC),WT-NC group,KO-NC group,WT-HFSD group and KO-HFSD group,each group of 7 mice.After 3 weeks of feeding,the mice in the HFSD group were injected intraperitoneally with STZ at a dose of 100 mg/kg body weight,and the corresponding group of NC mice were injected with the corresponding solvent as control.After 3 weeks of feeding,at the end of the 6th week,mice were fasted for 8 hours,and blood glucose was measured with a glucose meter.Mouse type 2 diabetes model standard:fasting blood glucose ≥ 11.1 mmol/L,and the emergence of polydipsia,polyuria,more food,weight gain is not obvious diabetes "more than three" symptoms.Results:Compared with NC group,the mice in HFSD group had higher body weight,and STZ was injected before.Compared with NC group,the body weight of HFSD group was not obvious.The difference was not significant.Before and after STZ injection,KO mice were fed with heat energy per day higher than WT group.After 3 weeks of feeding,the daily intake of KO mice in HFSD group and KO mice increased,NC group difference was not obvious.The fasting blood glucose of KO group was lower than that of WT group,and the fasting blood glucose of KO-NC group and WT-HFSD group was statistically significant(P<0.05)compared with WT-NC group before injection of STZ.After fasting for 3 weeks,the fasting blood glucose of HFSD group was higher than that of NC group,and fasting blood glucose≥11.1 mmol/L,compared with WT-NC group in KO-NC group and WT-HFSD group,And statistically significant(P<0.05).After 6 weeks of high fat and high sugar diet and injection of STZ100mg/kg,HFSD group of mice weight loss,increased heat intake,fasting blood glucose ≥ 11.1mmol/L(P<0.05).In summary,the success of mice with type 2 diabetes,fasting blood glucose ≥11.1mmol/L,and drink,polyuria,more food,weight gain is not obvious.Conclusion:Low-dose streptozotocin combined with high-fat and high-sugar diet induced the formation of type 2 diabetic mice.PART2:The effect of CYP1B1 knockout on cognitive impairment in type 2 diabetes mellitus in miceObjective:To investigate the effects of CYP1B1(cytochrome P450,family 1,subfamily B,polypeptide 1)knockout mice(KO)and wild type mice(WT)on high fat and high sucrose diet(HFSD)The expression of CYP1B1 gene knockout was observed under the model of type 2 diabetes mellitus by using low-dose streptozotocin(STZ).Methods:Wild type(WT)and CYP1B1 knockout type(KO)male mice were randomly divided into high fat and high sucrose diet(HFSD)and normal diet group(Normal chew,NC),WT-HFSD,KO-HFSD,WT-NC and KO-NC groups.After the model of type 2 diabetes mellitus was successfully modeled,the neurological behavior test-Morris water maze test and the avoidance test were used to detect the learning and memory ability of each group of mice.Morris water maze experiment,which includes a five-day placement navigation test(PNT)and the last day of the spatial search test(SPT)to detect the learning and memory abilities of each group of mice.The avoidance test included the training period,the test period and the extinction period,and recorded the latency of the mice before entering the darkroom and the number of times of entry in a certain period of time,which could reflect the memory of the mice.Results:The experimental results showed that the latency of the mice was shortened with the prolongation of training days,which indicated that the spatial learning and memory ability of mice increased with the increase of training times.The latency of HFSD-induced WT mice was significantly higher than that of NC group from day 3 to day 5,indicating that the learning ability was significantly impaired(P<0.05).Compared with WT-NC,the escape latency of KO-NC was significantly shorter and statistically significant(p<0.05).The escape latency of KO mice was shorter,both HFSD and NC.The KO-HFSD mice were significantly longer than those in the WT-HFSD group(P<0.05),indicating that the KO-HFSD group was significantly longer than that in the WT group(P<0.05),indicating that the CYP1B1 Gene knockout can improve the cognitive impairment caused by type 2 diabetes mellitus in mice,and has a protective effect on the learning and memory ability of type 2 diabetic mice.In the darkening experiment,there was no significant difference in the incubation period between the groups during the first day of training.There was a significant difference between the groups in the incubation period and the fifth day of the incubation period.NC group or HFSD group,KO group were higher than WT group,and KO-HFSD was lower than KO-NC,WT-HFSD was lower than WT-NC,but the next day and the fifth day of the regression period,KO-HFSD had a longer latency and was statistically significant(p<0.05)compared with WT-HFSD.In the training period,the test period and the extinction period,the number of training errors WT group was higher than that of KO group,and KO-HFSD was higher than KO-NC,WT-HFSD was higher than WT-NC,the second day of test period and the fifth day(P<0.05).Compared with WT-HFSD,KO-HFSD decreased the number of errors and was statistically significant(p<0.05).Conclusion:CYP1B1 knockout can improve the cognitive impairment induced by type 2 diabetes mellitus in mice,and it can protect the learning and memory ability of type 2 diabetic mice.PART3:Effect of CYP1B1 knockout on neurotrophic factors in low-dose streptozotocin combined with high-fat and high-sugar diet induced type 2 diabetes mellitusObjective:To investigate the effect of CYP1B1(cytochrome P450,family 1,subfamily B,polypeptide 1)knockout mice(KO)and wild-type(WT)mice in combination with low-dose streptozotocin Changes of nerve-related factors in type 2 diabetes mellitus.Methods:After the end of the neurobehavioral experiment,the mice were sacrificed and the mice were sacrificed.The cerebral cortex of each group was extracted.The total RNA was extracted by Trizol and the total RNA was extracted by real-time quantitative PCR(qRT-PCR)Cortical brain-derived neurotrophic factor(BDNF)levels.Results:Brain-derived neurotrophic factor(BDNF)could enhance the synaptic connection and affect the synthesis of neurotrophic factor and neurotransmitter,which was closely related to learning and memory.The level of Brain-derived neurotrophic factor(BDNF)mRNA in cerebral cortex was significantly higher than that in wild mice,and the level of BDNF gene in CYP1B1 knockout mice was significantly higher than that in wild mice The expression of BDNF mRNA in the cortex of the two groups was significantly decreased.Conclusion:CYP1B1 knockout can up-regulate the level of neurotrophic factor and up-regulate the expression of BDNF in normal diet.