二十碳五烯酸和二十二碳六烯酸及其组合对斑马鱼阿尔茨海默病模型认知障碍的改善作用和机制

Effect of EPA,DHA and their combination on cognitive impairment in zebrafish AD model and its mechanism

目的omega-3多不饱和脂肪酸二十碳五烯酸(eicosapentaenoic acid,EPA)和二十二碳六烯酸(docosahexaenoic acid,DHA)能够抑制M1型小胶质细胞的过度激活促炎细胞因子的释放和细胞凋亡,而EPA具有抗抑郁的作用。与EPA比较,DHA似对记忆的改善作用更强。由于两者在食物、衰老和疾病中的比值多变,其单一和最佳组合的功效不明,本实验拟利用AD模型比较研究EPA、DHA及最佳组合改善认知障碍及神经炎症的机制。方法Al 3+诱导斑马鱼AD模型,饲予EPA、DHA或EPA+DHA(1∶2),评估新物体识别和T迷宫奖赏的记忆,GC-MS检测躯体PUFAs浓度变化,qPCR检测脑内AChE、Axl、APP、Bace1、IL-6、TNF-α、CD11b、CD206、VDAC1、Caspase-3、Caspase-9和Bax的变化,ELISA试剂盒检测脑内Aβ的浓度。结果与模型组相比,EPA仅明显改善了斑马鱼的新物体识别能力,而DHA与EPA+DHA均恢复了新物体识别和T迷宫中的记忆。给予EPA、DHA和EPA+DHA均明显抑制了Aβ的蛋白浓度变化以及IL-6、CD206、Caspase-3、Caspase-9、Bax和AChE的mRNA表达,EPA和DHA均明显抑制了Bace1、APP和TNF-α的mRNA表达。DHA和EPA+DHA还明显降低了Axl和VDAC1的mRNA表达。结论EPA+DHA的组合对Al 3+诱导斑马鱼AD模型的记忆和认知障碍具有更好的改善作用,其作用机制可能通过抑制脑内细胞凋亡情况来改善记忆和认知障碍。

Aim To use the AD model to compare and study the mechanisms of EPA,DHA,the omega-3 polyunsaturated fatty acids,and their combination in improving cognitive impairment and neuroinflammation.Methods Zebra fish AD model was induced by Al 3+,fed with EPA,DHA or EPA+DHA(1∶2).New object recognition(NOR)and T-maze reward were used to evaluated the memory,GC-MS was used to detect PUFAs concentration changes in body,qPCR was applied to detect the changes of AChE,Axl,APP,Bace1,IL-6,TNF-α,CD11b,CD206,VDAC1,caspase-3,caspase-9 and Bax in brain,ELISA kit was employed to detect brain Aβconcentration.Results Compared with the model group,EPA only significantly improved zebra fish NOR ability,while DHA and EPA+DHA both restored NOR and memory in the T-maze.EPA,DHA and EPA+DHA significantly inhibited Aβprotein concentration change and mRNA expression of IL-6,CD206,caspase-3,caspase-9,Bax,and AChE.EPA and DHA significantly inhibited Bace1,APP,and TNF-αmRNA expression.DHA and EPA+DHA significantly reduced Axl and VDAC1 mRNA expression.Conclusions The combination of EPA and DHA has a better effect on memory and cognitive impairment in zebra fish AD model induced by Al 3+,and its mechanism may be improving memory and cognitive impairment via inhibiting brain cell apoptosis.