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.

The mechanism of Yinchenhao decoction in treating obstructivejaundice- induced liver injury based on Nrf2 signaling pathway

BACKGROUND Obstructive jaundice(OJ)is caused by bile excretion disorder after partial or complete bile duct obstruction.It may cause liver injury through various mechanisms.Traditional Chinese medicine(TCM)has a lot of advantages in treating OJ.The recovery of liver function can be accelerated by combining Chinese medicine treatment with existing clinical practice.Yinchenhao decoction(YCHD),a TCM formula,has been used to treat jaundice.Although much progress has been made in recent years in understanding the mechanism of YCHD in treating OJ-induced liver injury,it is still not clear.AIM To investigate chemical components of YCHD that are effective in the treatment of OJ and predict the mechanism of YCHD.METHODS The active components and putative targets of YCHD were predicted using a network pharmacology approach.Gene Ontology biological process and Kyoto Encyclopedia of Genes and Genomes path enrichment analysis were carried out by cluster profile.We predicted the biological processes,possible targets,and associated signaling pathways that YCHD may involve in the treatment of OJ.Thirty male Sprague–Dawley rats were randomly divided into three groups,each consisting of 10 rats:the sham group(Group S),the OJ model group(Group M),and the YCHDtreated group(Group Y).The sham group only received laparotomy.The OJ model was established by ligating the common bile duct twice in Groups M and Y.For 1 wk,rats in Group Y were given a gavage of YCHD(3.6 mL/kg)twice daily,whereas rats in Groups S and M were given the same amount of physiological saline after intragastric administration daily.After 7 d,all rats were killed,and the liver and blood samples were collected for histopathological and biochemical examinations.Total bilirubin(TBIL),direct bilirubin(DBIL),alanine aminotransferase(ALT),and aspartate transaminase(AST)levels in the blood samples were detected.The gene expression levels of inducible nitric oxide synthase(iNOS)and endothelial nitric oxide synthase(eNOS),and the nucleus positive rate of NF-E2 related factor 2(Nrf2)protein were measured.Western blot analyses were used to detect the protein and gene expression levels of Nrf2,Kelchlike ECH-associated protein 1,NAD(P)H quinone dehydrogenase 1(NQO1),and glutathione-Stransferase(GST)in the liver tissues.One-way analysis of variance was used to evaluate the statistical differences using the statistical package for the social sciences 23.0 software.Intergroup comparisons were followed by the least significant difference test and Dunnett’s test.RESULTS The effects of YCHD on OJ involve biological processes such as DNA transcription factor binding,RNA polymerase II specific regulation,DNA binding transcriptional activator activity,and nuclear receptor activity.The protective effects of YCHD against OJ were closely related to 20 pathways,including the hepatitis-B,the mitogen-activated protein kinase,the phosphatidylinositol 3-kinase/protein kinase B,and tumor necrosis factor signaling pathways.YCHD alleviated the swelling and necrosis of hepatocytes.Following YCHD treatment,the serum levels of TBIL(176.39±17.03μmol/L vs 132.23±13.88μmol/L,P<0.01),DBIL(141.41±14.66μmol/L vs 106.43±10.88μmol/L,P<0.01),ALT(332.07±34.34 U/L vs 269.97±24.78 U/L,P<0.05),and AST(411.44±47.64 U/L vs 305.47±29.36 U/L,P<0.01)decreased.YCHD promoted the translocation of Nrf2 into the nucleus(12.78±0.99%vs 60.77±1.90%,P<0.001).After YCHD treatment,we found a decrease in iNOS(0.30±0.02 vs 0.20±0.02,P<0.001)and an increase in eNOS(0.18±0.02 vs 0.32±0.02,P<0.001).Meanwhile,in OJ rats,YCHD increased the expressions of Nrf2(0.57±0.03 vs 1.18±0.10,P<0.001),NQO1(0.13±0.09 vs 1.19±0.07,P<0.001),and GST(0.12±0.02 vs 0.50±0.05,P<0.001),implying that the potential mechanism of YCHD against OJ-induced liver injury was the upregulation of the Nrf2 signaling pathway.CONCLUSION OJ-induced liver injury is associated with the Nrf2 signaling pathway.YCHD can reduce liver injury and oxidative damage by upregulating the Nrf2 pathway.

Pathophysiological consequences and treatment strategy of obstructive jaundice

Obstructive jaundice(OJ)is a common problem in daily clinical practice.However,completely understanding the pathophysiological changes in OJ remains a challenge for planning current and future management.The effects of OJ are widespread,affecting the biliary tree,hepatic cells,liver function,and causing systemic complications.The lack of bile in the intestine,destruction of the intestinal mucosal barrier,and increased absorption of endotoxins can lead to endotoxemia,production of proinflammatory cytokines,and induce systemic inflammatory response syndrome,ultimately leading to multiple organ dysfunction syndrome.Proper management of OJ includes adequate water supply and electrolyte replacement,nutritional support,preventive antibiotics,pain relief,and itching relief.The surgical treatment of OJ depends on the cause,location,and severity of the obstruction.Biliary drainage,surgery,and endoscopic intervention are potential treatment options depending on the patient's condition.In addition to modern medical treatments,Traditional Chinese medicine may offer therapeutic benefits for OJ.A comprehensive search was conducted on PubMed for relevant articles published up to August 1970.This review discusses in detail the pathophysiological changes associated with OJ and presents effective strategies for managing the condition.