ABSTRACT
ObjectiveTo investigate the effects of Lactobacillus rhamnosus GG （LGG）on microglia and Tau phosphorylation in the hippocampus of aged mice induced by anesthesia and surgery. MethodsA total of thirty 18-month-old C57BL/6J mice were randomly divided into three groups： control group， anesthesia surgery group， and anesthesia surgery + LGG group （10 mice/group）. The aged mice were oral administered by NS or LGG 109 CFU 150 μL once a day for 20 days. Then anesthesia surgery group and anesthesia surgery +LGG group received anesthesia with isoflurane and exploratory laparotomy. The activation status of microglia in the hippocampus was detected by immunofluorescence staining 12 hours after surgery. IL-6 concentration changes was detected by ELISA. The expression changes of Tau protein phosphorylation site （Tau-pS202/pT205） and total Tau protein was detected by western blot. ResultsThe microglia in the hippocampus of the control group were in a resting state， and the concentration of inflammatory factor IL-6 was （82.08 ± 12.07） pg/mL in control group. Compared to the control group， the anesthesia surgery group showed microglial cell Microglia were activated， the concentration of inflammatory factors IL-6 increased significantly to （123.7±5.72） pg/mL （P=0.000）， and the expression of phosphorylated Tau-pS202/pT205 increased the hippocampus （P=0.002）. Compared to the anesthesia surgery group， the activated microglia were inhibited， the concentration of IL-6 decreased to （96.68±9.59） pg/mL （P=0.008）， and the expression of phosphorylated Tau-pS202/pT205 reduced significantly in the AS+LGG group （P=0.002）. While there were no significant changes in total Tau protein among 3 groups. ConclusionPreoperative administration of probiotic LGG can alleviate the activation of microglia， increased secretion of inflammatory factors， and increased Tau protein phosphorylation levels in the hippocampus of elderly mice caused by anesthesia surgery.
ABSTRACT
Objective To investigate the effect and mechanisms of pioglitazone on post operative cognitive function induced by surgery in elderly rats.Methods Elderly SD rats,male and weighing 220-250 g,were randomly divided into control group (group Con),surgery group (group S),pioglitazone group (group P)and pioglitazone/surgery group (group PS).The level of glycemia was measured by glucometer after completing the surgical model.The expression of advanced glycation endproducts (AGEs)in hippocampal tissues was detected by western blot and reactive oxy-gen species (ROS)and IL-6 by ELISA 1 2 h after surgery.Morris water maze was used for evaluation of cognitive function 4 days after surgery.Results Compared with group Con,group S showed a sig-nificant increase in the expression of AGEs and IL-6 and the level of ROS (P<0.05);Compared with group S,the expression of AGEs and IL-6 and the level of ROS decreased significantly in group PS (P<0.05).Compared to group Con,the surgery increased the average time of escape latencies on the 8th days and 10th days after surgery and reduced the platform-crossing times in the Morris water maze test (P<0.05).Compared with group S,group PS showed a significant decrease in the average time of escaping latencies on the 10th day after surgery (P<0.05),and an increased platform-cross-ing times in the Morris water maze test (P<0.05).Conclusion These results suggest that pioglita-zone attenuates postoperative cognitive function and its mechanism may be related to the decrease of the expression of AGEs and IL-6 and the level of ROS.