Yinchenhao decoction attenuates obstructive jaundice-induced liver injury and hepatocyte apoptosis by suppressing protein kinase RNA-like endoplasmic reticulum kinase-induced pathway

BACKGROUND Chronic biliary obstruction results in ischemia and hypoxia of hepatocytes,and leads to apoptosis.Apoptosis is very important in regulating the homeostasis of the hepatobiliary system.Endoplasmic reticulum(ER)stress is one of the signaling pathways that induce apoptosis.Moreover,the protein kinase RNA-like endoplasmic reticulum kinase(PERK)-induced apoptotic pathway is the main way;but its role in liver injury remains unclear.Yinchenhao decoction(YCHD)is a traditional Chinese medicine formula that alleviates liver injury and apoptosis,yet its mechanism is unknown.We undertook this study to investigate the effects of YCHD on the expression of ER stress proteins and hepatocyte apoptosis in rats with obstructive jaundice(OJ).AIM To investigate whether YCHD can attenuate OJ-induced liver injury and hepatocyte apoptosis by inhibiting the PERK-CCAAT/enhancer-binding protein homologous protein(CHOP)-growth arrest and DNA damage-inducible protein 34(GADD34)pathway and B cell lymphoma/leukemia-2 related X protein(Bax)/B cell lymphoma/leukemia-2(Bcl-2)ratio.METHODS For in vivo experiments,30 rats were divided into three groups:control group,OJ model group,and YCHD-treated group.Blood was collected to detect the indicators of liver function,and liver tissues were used for histological analysis.For in vitro experiments,30 rats were divided into three groups:G1,G2,and G3.The rats in group G1 had their bile duct exposed without ligation,the rats in group G2 underwent total bile duct ligation,and the rats in group G3 were given a gavage of YCHD.According to the serum pharmacology,serum was extracted and centrifuged from the rat blood to cultivate the BRL-3A cells.Terminal deoxynucleotidyl transferase mediated dUTP nick end-labelling(TUNEL)assay was used to detect BRL-3A hepatocyte apoptosis.Alanine aminotransferase(ALT)and aspartate transaminase(AST)levels in the medium were detected.Western blot and quantitative real-time polymerase chain reaction(qRT-PCR)analyses were used to detect protein and gene expression levels of PERK,CHOP,GADD34,Bax,and Bcl-2 in the liver tissues and BRL-3A cells.RESULTS Biochemical assays and haematoxylin and eosin staining suggested severe liver function injury and liver tissue structure damage in the OJ model group.The TUNEL assay showed that massive BRL-3A rat hepatocyte apoptosis was induced by OJ.Elevated ALT and AST levels in the medium also demonstrated that hepatocytes could be destroyed by OJ.Western blot or qRT-PCR analyses showed that the protein and mRNA expression levels of PERK,CHOP,and GADD34 were significantly increased both in the rat liver tissue and BRL-3A rat hepatocytes by OJ.The Bax and Bcl-2 levels were increased,and the Bax/Bcl-2 ratio was also increased.When YCHD was used,the PERK,CHOP,GADD34,and Bax levels quickly decreased,while the Bcl-2 levels increased,and the Bax/Bcl-2 ratio decreased.CONCLUSION OJ-induced liver injury and hepatocyte apoptosis are associated with the activation of the PERK-CHOP-GADD34 pathway and increased Bax/Bcl-2 ratio.YCHD can attenuate these changes.

NF-κB p65介导的前列腺素E2分泌及DNA结合抑制因子2蛋白表达在促进大鼠桡骨骨折早期愈合的作用

目的骨再生过程包含一系列复杂的分子信号途径,通过探讨NF-κB作为骨折愈合过程中"关键性激活点"的可能性,为基因治疗骨折延迟愈合和骨不连提供实验依据。方法取6～7周龄Wistar雄性大鼠33只,体重180～220 g,随机分为4组。对照组(A组,n=3)、单纯NF-κB抑制剂Bay 11-7082处理组(B组,n=6):分别在大鼠右前肢桡骨中下段经皮注射0.3 mL生理盐水或含50μmol/L Bay 11-7082的生理盐水,每天1次,持续至处死。单纯骨折组(C组,n=12)、Bay 11-7082干预骨折组(D组,n=12):制备右侧桡骨中下段骨折模型后,C组不作任何处理,D组处理方法同B组。观察大鼠一般情况,A组于注射后7 d,B、C、D组于注射后3、7 d取标本行ALP活性、前列腺素E2(prostaglandins E2,PGE2)含量检测以及Western blot检测NF-κB p65、BMP-7和DNA结合抑制因子2(inhibitor of DNA binding 2,Id2),并取C、D组14、28 d标本行HE染色观察。结果各组大鼠均存活至实验完成。注射后3、7 d B组ALP活性及PGE2含量与A组比较,差异均无统计学意义(P>0.05);C组较A组增高,D组较A组降低,差异均有统计学意义(P<0.01)。注射后3、7 d,各组骨折端组织中均见NF-κB p65、BMP-7、Id2表达,B组各因子表达水平与A组比较,差异均无统计学意义(P>0.05);C组NF-κB p65和BMP-7蛋白表达水平较A组增高,Id2蛋白表达水平较A组降低,差异均有统计学意义(P<0.01);D组NF-κB p65、BMP-7蛋白表达水平较A组降低,Id2蛋白表达较A组增高,差异均有统计学意义(P<0.01)。组织学观察示,注射后14、28 d C组骨折端组织见大量骨性骨痂,而D组28 d时才见骨性骨痂。结论 NF-κB p65可通过调控PGE2分泌以及BMP-7和Id2蛋白表达促进大鼠桡骨骨折的早期愈合。

预知子提取物对抑郁症大鼠海马神经可塑性相关蛋白BDNF/CREB/Bcl-2的影响研究

探讨预知子提取物对抑郁症大鼠海马神经可塑性相关蛋白BDNF/CREB/Bcl-2的影响。90只SD大鼠,随机选取10只,设为A组(空白对照组),常规饲养;其余80只随机分为2组,B组(模型对照组)和C组(预知子提取物干预组),每组各40只,均予以抑郁大鼠模型制备。C组予以预知子提取物干预,每天灌胃1次,直至B组全部大鼠均达到抑郁模型标准。计算C组预知子提取物干预有效率。A组、B组、C1组、C2组各随机选取6只大鼠,剥离海马组织,常规病理染色,光镜下观察海马的组织形态学变化;同时检测海马BDNF/CREB/Bcl-2蛋白的表达。C组预知子提取物干预有效率为69. 23%。B组大鼠海马神经细胞排列稀疏散乱,细胞间隙增大、数量明显减少,核深染。C1组、C2组大鼠海马神经细胞数量增多,细胞间隙明显缩小,海马损伤明显减轻。与A组比较,B组大鼠海马中BDNF、CREB、Bcl-2相对灰度值均显著降低(P <0. 01);与B组比较,C1组、C2组大鼠海马中BDNF、CREB、Bcl-2相对积分光密度值均不同程度增高(P <0. 05或P <0. 01);C2组大鼠海马中BDNF、CREB、Bcl-2相对积分光密度值均高于C1组相应水平(P <0. 05)。预知子提取物可改善抑郁症大鼠海马神经可塑性相关蛋白BDNF/CREB/Bcl-2的水平,可能对抑郁损伤具有一定的保护作用。