Research Papers
SHENG Ke-Yan, CHEN Yu-Yan, GAO Yuan, ZHANG Bao-Wen, ZHANG Meng, WANG Zhi, KOU Xian-Juan
Cognitive dysfunction is one of the serious complications of type 2 diabetes. Exercise intervention has a certain effect on improving diabetes cognition, but the exact process remains ambiguous.This research aims to explore the impact and molecular processes of treadmill exercises in enhancing cognitive impairments in type 2 diabetic mice. Ten m/m 8-week-old male mice were used as the control group. Forty db/db mice, each 8 weeks old and male, were categorized into four distinct groups with each group containing 10 mice, including the db/db group (model group), db+Exe group (exercise group), db+Exe+SB203580 group (exercise combined with the p38 MAPK inhibitor group), db+SB203580 group (p38 MAPK inhibitor group). db+Exe group and db+Exe+SB203580 group were subjected to treadmill running intervention (40min/time, 5 times / week, a total of 8 weeks). db+Exe+SB203580 and db+SB203580 group were intraperitoneally injected with SB203580 (5 mg/kg, 5 times/week, 8 weeks) 2 hours before treadmill exercise. The results of body weights and fasting blood glucose measurement showed that 8-week treadmill exercise could significantly reduce the body mass and fasting blood glucose levels (P<0.01); the results of water maze showed that treadmill exercise improved cognitive dysfunction in diabetic mice (P<0.05). Immunofluorescence staining revealed that treadmill exercise diminished the fluorescence intensity of NLRP3 in hippocampus, and there was a significant difference in CA1 and CA3 regions (P<0.05). Treadmill exercise reduced the fluorescence intensity of PI in the hippocampus, and there was a significant difference in the DG region (P<0.01). The results of qRT-PCR revealed that treadmill exercise decreased IL-1β and IL-18 mRNA levels in hippocampus, with a notable difference in IL-1β mRNA levels(P<0.05). Western blotting analysis revealed that treadmill exercise reduced the concentrations of Caspase3, Caspase9 and Bax in hippocampus (P<0.01), reduced the concentrations of TXNIP, NLRP3, GSDMD-N, IL-1β, IL-18, Cleaved Caspase1 and Caspase1 (P<0.05), decreased the levels of p-RIPK1, RIPK1, p-RIPK3 and RIPK3 (P<0.05). After adding p38 inhibitors, treadmill exercise combined with p38 inhibitor intervention further inhibited the expression of Caspase3, TXNIP, GSDMD-N and IL-18 (P<0.05), and the expression levels of Caspase9, Bax, NLRP3, IL-1β, Cleaved Caspase 1 and Caspase 1 also showed a downward trend. The expression of RIPK1 and p-RIPK3 increased significantly (P<0.05), and the protein expression levels of p-p38, p-RIPK1 and RIPK3 showed an upward trend. In conclusion, treadmill running intervention can effectively improve the cognitive dysfunction in type 2 diabetic mice, and its mechanism is partly through the p38 MAPK signaling pathway to regulate PANoptosis.