丰富环境对脓毒症相关性小鼠认知功能障碍的影响

Effects of environmental enrichment on cognitive dysfunction in sepsis-related mice

目的:探讨幼年期丰富环境(EE)对脂多糖(LPS)诱导的小鼠认知功能障碍及海马区小胶质细胞活化的影响。方法:36只幼年雌性昆明小鼠随机分为对照组(Control)、脂多糖(LPS)组、丰富环境+脂多糖组(EE+LPS)。给予小鼠单次腹腔注射LPS(O.83 mg/kg)构建脓毒症小鼠模型.EE+LPS组小鼠在注射LPS前给予8周的丰富环境干预。新旧事物识别实验检测小鼠认识功能,免疫组织化学法检测小鼠海马区lba-1的表达,Western Blot检测CD68和IL-1β的表达。结果:与Control组相比,LPS组小鼠新事物辨别指数明显下降;与LPS组相比,EE+LPS组小鼠新事物辨别指数明显增加。LPS可诱导小鼠海马区小胶质细胞活化,表现为Iba-1阳性细胞数目增加,CD68和IL-1β的上调;而丰富环境干预可明显抑制小胶质细胞活化,表现为lba-1阳性细胞数目减少,CD68和IL-1β表达下调。结论:丰富环境可能通过抑制海马区小胶质细胞的激活从而改善LPS诱导的小鼠认知功能障碍。

Objective:To investigate the efeets of environmental enrichment(EE)on cognitive dysfunction in sep-sis-related mice.Methods:Thirty six young female Kunming mice were randomized into three groups:Control group,LPS group and EE+LPS group.The mice of cognitive dysfunction model were injected with LPS(0.83 mg/kg),and.the EE+LPS group was given env ironmental enrichment intervention for 8 weeks before injection.Cognitive function is determined by novelty object recognition lest.The expression of Iba-1 in hippocampus of mice was determined by immu-nohistochemical staining.The expression of CD68 and IL-1βin hippocampus was assayed by Western Blot.Results:Compared with control group,the mice of LPS group showed decreased discrimination ratio in novelty object recognition task.Compared with LPS group,the mice of EE+LPS showed significant increase on the discrimination ratio.The expressions of Ilba-l,CD68 and IL-1βin LPS group were obviously more than those in control group,and environmental enrichment administration significantly decreased LPS-induced Iba-1,CD68 and IL-1βexpressions.Conclusion:Our finding indicates that EE could improve LPS-induced cognitive impaiment in mice by inhibiting microglia activation in the hippocampus.