补肾益智方通过调节eIF2α/ATF4信号通路抑制内质网应激改善铝暴露模型斑马鱼认知功能障碍的机制研究OA

Objective:To investigate the pharmacological effect and mechanism of Bushen Yizhi(补肾益智)For-mula(BSYZ)in treating aluminum-induced cognitive impairment in zebrafish.Methods:A total of 170 six-month-old individuals of zebrafish were grouped as follows:control,model(aluminum exposure at 0.01 μg/mL),donepezil hydro-chloride(1 μg/mL),and BSYZ(156 μg/mL and 312 μg/mL)groups.After four weeks of drug intervention,the T-maze test,novel object recognition test,and latency to enter the enriched chamber(EC)were employed to evaluate the spatial memory and learning abilities of zebrafish in each group.Hematoxylin-eosin staining was performed to observe the brain tissue structure,thioflavin S staining to assess the amyloid plaque deposits in the brain tissue,and terminal-deoxy-nucleotidyl transferase-mediated dUTP nick end labeling to assess cell apoptosis.Enzyme-linked immunosorbent assay was employed to determine the levels of inflammatory cytokines including tumor necrosis factor(TNF)-α,interleukin(IL)-1β,and acetylcholinesterase(AChE)in the brain tissue.Immunofluorescence staining was used to detect the ex-pression of C-EBP homologous protein(CHOP)and activating transcription factor 4(ATF4).Western blotting was per-formed to examine the expression levels of apoptosis-related proteins[CHOP,B-cell lymphoma 2(BCL-2),and BCL-2-associated X protein(BAX)]and endoplasmic reticulum stress-related proteins[eukaryotic translation initiation factor 2(eIF2α),phosphorylated eIF2α(p-eIF2α),and ATF4].Results:Compared with the control group,the model group ex-hibited decreased learning and memory abilities,prolonged T-maze latency time(P<0.01),reduced new object recogni-tion index and preference index(P<0.05),structural damage in the brain tissue,increased pathologic plaques and AChE deposition(P<0.01),declined levels of TNF-α and IL-1(P<0.05),down-regulated protein levels of BAX/BCL-2 and ATF4(P<0.05),and up-regulated protein levels of CHOP and p-eIF2(P<0.01).Compared with the model group,the BSYZ(312 μg/mL)group showed improved new object recognition index(P<0.05),shortened T-maze latency time(P<0.01),alleviated the aluminum-induced occurrence of lesions,and reduced amyloid deposition in the brain tissue(P<0.01),lowered levels of TNF-α(P<0.01),IL-1e(P<0.01),and AChE(P<0.01),reduced cell apoptosis(P<0.01),and down-regulated protein levels of BAX/BCL-2(P<0.05),CHOP(P<0.01),p-eIF2p(P<0.01),and ATF4(P<0.05).Conclusion:BSYZ can ameliorate aluminum-induced cognitive impairment,inflammation,AChE accumula-tion,and neuronal apoptosis in the brain tissue of zebrafish by regulating the eIF2α/ATF4 pathway.