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(...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.展开更多
Objective: To investigate the expression of lipopolysaccharide binding protein (LBP) and its gene in rats with endotoxemia and explore the role of LBP in the response of host to endotoxin. Methods: Thirty Wistar rats ...Objective: To investigate the expression of lipopolysaccharide binding protein (LBP) and its gene in rats with endotoxemia and explore the role of LBP in the response of host to endotoxin. Methods: Thirty Wistar rats were divided randomly into five groups: the normal group and the endotoxemia groups (1, 3, 6, 12 hours after LPS injection, respectively). The level of plasma endotoxin was determined by the Limulus Amebocyte Lysate assay. The expression of LBP mRNA in hepatic tissue was examined by reverse transcription polymerase chain reaction (RT PCR). Plasma levels of LBP, tumor necrosis factor (TNF) α and interleukin (IL) 6 were measured by enzyme linked immunosorbent assay (ELISA). Morphologic changes of hepatic tissue were observed under transmission electron microscope. Results: The level of plasma endotoxin peaked at 1 h after LPS injection, then declined, but was still higher than that of the normal group at 12 h; intrahepatic expression of LBP mRNA and plasma LBP increased with time after LPS stimulation; TNF α and IL 6 in plasma increased with upregulation of LBP expression; there were significant differences between the normal group and endotoxemia groups (P< 0.05 ). Activation of Kupffer cells and injury of hepatocytes could be seen in rats with endotoxemia. Conclusions: LPS can upregulate the intrahepatic expression of LBP mRNA and increase the plasma LBP level. Under certain conditions, LBP may enhance the sensitivity of host to the toxic effects of LPS.展开更多
基金Supported by the National Natural Science Foundation of China,No.81273952
文摘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.
基金theNationalNaturalScienceFoundationofChina (No .39970 71930 170 919)
文摘Objective: To investigate the expression of lipopolysaccharide binding protein (LBP) and its gene in rats with endotoxemia and explore the role of LBP in the response of host to endotoxin. Methods: Thirty Wistar rats were divided randomly into five groups: the normal group and the endotoxemia groups (1, 3, 6, 12 hours after LPS injection, respectively). The level of plasma endotoxin was determined by the Limulus Amebocyte Lysate assay. The expression of LBP mRNA in hepatic tissue was examined by reverse transcription polymerase chain reaction (RT PCR). Plasma levels of LBP, tumor necrosis factor (TNF) α and interleukin (IL) 6 were measured by enzyme linked immunosorbent assay (ELISA). Morphologic changes of hepatic tissue were observed under transmission electron microscope. Results: The level of plasma endotoxin peaked at 1 h after LPS injection, then declined, but was still higher than that of the normal group at 12 h; intrahepatic expression of LBP mRNA and plasma LBP increased with time after LPS stimulation; TNF α and IL 6 in plasma increased with upregulation of LBP expression; there were significant differences between the normal group and endotoxemia groups (P< 0.05 ). Activation of Kupffer cells and injury of hepatocytes could be seen in rats with endotoxemia. Conclusions: LPS can upregulate the intrahepatic expression of LBP mRNA and increase the plasma LBP level. Under certain conditions, LBP may enhance the sensitivity of host to the toxic effects of LPS.
