脑蛋白水解物通过p38 MAPK信号通路降低阿尔茨海默病小鼠的细胞凋亡、炎症及氧化应激水平

The p38 MAPK signaling pathway mediates the reduction of apoptosis,inflammation and oxidative stress levels in AD mice by cerebroprotein

目的探讨脑蛋白水解物(cerebroprotein hydrolysate for injection I,CH-I)对阿尔茨海默病(Alzheimer's disease,AD)小鼠学习记忆能力、凋亡和氧化应激的影响及机制。方法采用β淀粉样蛋白(β-Amyloid,Aβ1-42)海马内注射建立AD小鼠模型,实验分为对照(control,Con)组、Aβ组、Aβ+CH-I组、CH-I组。以新物体实验和Y迷宫检测小鼠学习记忆能力;酶联免疫吸附试验检测脑组织超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)、过氧化氢酶(catalase,CAT)活力;Tunel染色检测细胞凋亡水平;提取Aβ组和Aβ+CH-I组小鼠海马mRNA进行转录组测序(RNA sequencing,RNA-seq)及生物信息学分析和验证;通过蛋白质免疫印迹(Western blotting,WB)实验检测应激活化蛋白激酶(c-Jun N-terminal kinase,JNK)、丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)、p38 MAPK磷酸化蛋白和总蛋白及炎性反应表达。结果与Con组和Aβ+CH-I组比较,Aβ小鼠组新异臂/物体探索时间百分比显著降低;Aβ组小鼠SOD、GSH-Px活性显著低于Con组和Aβ+CH-I组,差异有统计学意义;RNA-seq测序显示与Aβ组相比,Aβ+CH-I组MAPK信号通路及炎性因子相关基因显著下调;通过WB证实与Aβ组相比,Aβ+CH-I组凋亡水平、p38 MAPK蛋白及炎性反应水平显著下降。结论CH-I可能通过调控p38 MAPK信号通路保护神经元免受氧化应激及凋亡从而介导神经细胞的保护作用。

Objective Our objective was to examine the potential of cerebroprotein hydrolysate for injection I(CH-I)in mitigating oxidative stress,apoptosis,and neuroinflammation in an Alzheimer s disease(AD)model,while also gaining a better understanding of the underlying mechanisms.Methods AD mouse model was established through the intrahippocampal injection of amyloid-β1-42.The experiment consisted of four groups:Control(Con)group,Aβgroup,Aβ+CH-I group,and CH-I group.The learning and memory abilities of the mice were assessed using the new object recognition experiment and Y-maze.Enzyme-linked immunosorbent assay was employed to measure the activity of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),thioredoxin,and catalase(CAT)in brain tissue.Additionally,Tunel staining was utilized to evaluate the levels of cell apoptosis.Aβgroup and Aβ+CH-I group were extracted for RNA-seq and bioinformatics analysis and verification.Western blotting analysis was conducted to detect proteins associated with the pathway[c-Jun N-terminal kinase(JNK),mitogen-activated protein kinase(MAPK),p38 MAPK].Results In comparison to the Con group and the Aβ+CH-I group,the Aβgroup exhibited a significant decrease in the proportion of time allocated to exploring novel arms/objects.Moreover,the Aβgroup displayed significantly lower levels of SOD and GSH-Px activities in mice,in contrast to both the Con group and the Aβ+CH-I group,with statistically significant distinctions.The RNA-seq analysis demonstrated a significant downregulation of the MAPK signaling pathway in the Aβ+CH-I group compared to the Aβgroup.Additionally,the Aβ+CH-I group exhibited noteworthy reductions in apoptosis levels,p38 MAPK protein,and inflammation levels when compared to the Aβgroup.Conclusions CH-I exerts neuroprotective effects through the modulation of the p38 MAPK signaling pathway,thereby conferring neuronal resistance against oxidative stress and apoptosis.