Study Of Socs1Gene And Glucocorticoid Treatment In Acute-on-Chronic Hepatitis B Liver Failure

Section ⅠMETHYLATION OF SUPPRESSOR OF CYTOKINE SIGNALING1GENE PROMOTER IS ASSOCIATED WITHACUTE-ON-CHRONIC HEPATITIS B LIVER FAILUREBackgroundHepatitis B virus (HBV) infection is a significant worldwide health problem with higher prevalence and more than400million persons estimated to be chronically infected in Asia. The progression of chronic HBV infection may lead to the condition of liver failure which is defined as acute-on-chronic hepatitis B liver failure (ACHBLF). ACHBLF can eventually cause multiple organ dysfunction syndrome (MODS), accompanied by complications of sepsis, upper gastrointestinal bleeding, ischemia or additional superimposed liver injury with a poor prognosis and high mortality rate. Correspondingly, there is less study about the characteristics and pathogenesis of ACHBLF.Clinical researches have shown that uncontrolled hepatic immunoactivation makes the elevated level of pro-inflammatory cytokines evocable. Those pro-inflammatory cytokines induce apoptosis of hepatocyte and regeneration inhibitory state of hepatic failure. In addition, the activation of lymphocytes by these cytokines could also lead to immunopathological effects and systemic inflammatory response. In a word, cytokines directly involve in the evolution and exacerbation of ACHBLF.Most signal transduction of pro-inflammatory cytokines was through the Janus kinase(JAK)/signal transducer and activator of transcription (STAT) signal transduction pathway which plays an important role in the regeneration of hepatocytes. The intension and duration of cytokine effect are tightly controlled by several mechanisms, including the suppressors of cytokine signaling (SOCS). SOCS1, member of the SOCS protein family, contains a center SH2domain and a unique carboxyl SOCS box. In the pathogenesis of liver failure, SOCS1serves a regulatory mechanism to limit cytokine-mediated inflammation after hepatic ischemia reperfusion injury. SOCSl plays a critical role in negative regulation of inflammatory and immune homeostasis. But the research of SOCSl gene was limited on chronic liver disease, especially on ACHBLF.In the present study, we identified the presence of SOCSl gene methylation changes in ACHBLF. We assessed the level of pro-inflammatory cytokines and expression of SOCSl in CHB and ACHBLF patients. The results obtained were then correlated with the findings from pathological studies to define the clinical significance of aberrant DNA methylation in ACHBLF.ObjectiveThis present study was therefore to identify the potential role of SOCS1and its promoter methylation pattern in the patients with acute-on-chronic hepatitis B liver failure (ACHBLF). Materials and MethodsSixty ACHBLF patients,60chronic hepatitis B (CHB) patients and30healthy controls were investigated in this study. SOCSl mRNA level in peripheral blood mononuclear cells (PBMCs) was determined by quantitative real-time PCR. Plasma levels of interleukin (IL)-6, interferon (IFN)-γ and tumor necrosis factor (TNF)-α were detected by enzyme-linked immunosorbent assay (ELISA). Methylation of SOCSl promoter from PBMCs was determined using methylation-specific polymerase chain reaction (PCR). Furthermore, this methylation status was compared with clinical findings and cytokine levels.ResultsExpression of SOCSl mRNA in CHB and ACHBLF patients was significantly higher than that in healthy controls. The serum level of IL-6, IFN-y and TNF-a was significantly higher in ACHBLF than CHB. Increased serum level of IL-6, IFN-y and TNF-α was correlated with total bilirubin, ALT, PTA and MELD scores in ACHBLF. The degree of methylation of the SOCS1in ACHBLF patients (35.0%,21/60) was significantly higher than that in CHB patients (16.7%,10/60). Furthermore, methylated group showed lower level of SOCS1higher MELD scores and mortality rate when when compared with unmethylated group of ACHBLF.ConclusionsThese results suggested that SOCSl might contribute to immune-related liver damage in ACHBLF and its aberrant methylation may be a key event for the prognosis of ACHBLF.Section IIPROGNOSES OF PATIENTS WITH ACUTE-ON-CHRONIC HEPATITIS B LIVER FAILURE ARE CLOSELY ASSOCIATED WITH ALTERED SOCS1MRNA EXPRESSION AND CYTOKINE PRODUCTION FOLLOWING GLUCOCORTICOID TREATMENTBackgroundThe pathogenesis of ACHBLF was related to immune-mediated liver injury and over enhancement of immunologic function. The immunopathologic damage and microcirculation disturbance could lead to liver cells in ischemia, hypoxia, and edema. Previous studies suggested that the use of corticosteroids was crucial to prevent liver cell necrosis when used in the early stage of severe hepatitis. The adrenal insufficiency in liver diseases makes it reasonable to introduce sufficient doses of corticosteroids in the early stage of liver failure. As an optional therapy for ACHBLF, the corticosteroids treatment has received many attentions. Glucocorticoid suppressed the inflammation by controlling and preventing the immune-correlated damages. The upregulation of SOCS1by corticosteroids has been established both in vivo and vitro, which suggested that cortisol may be playing a key role in suppressing cytokine signaling and the associated inflammatory response through SOCS1. However, the effect of glucocorticoid on SOCS1remains unclear in ACHBLF.ObjectiveIn the present study, we explored the inflammatory cytokine levels and SOCS1gene mRNA expression in peripheral blood mononuclear cells (PBMCs) before and after glucocorticoid treatment in ACHBLF patients. We also investigated the correlation between SOCS1expression, model for end-stage liver disease (MELD) scores and mortality rates. Furthermore, the SOCS1promoter methylation status in different stages of glucocorticoid treatment were more intensively analyzed to verify the potentially role of methylation and effect of corticoids on the prognosis of patients with ACHBLF.Materials and MethodsFourty-seven ACHBLF patients receiving four weeks’ glucocorticoid treatment and30healthy controls were investigated to determine the potential effects of glucocorticoid on the transcriptional level of SOCS1in peripheral blood mononuclear cells (PBMCs). SOCS1mRNA level and IFN-γ-responsive/STAT1-dependent genes expression was determined by quantitative real-time PCR. Plasma levels of interleukin (IL)-6and tumor necrosis factor (TNF)-α were detected by enzyme-linked immunosorbent assay (ELISA). Methylation of SOCSl promoter was determined using methylation-specific polymerase chain reaction (PCR) before and after glucocorticoid treatment. Furthermore, this methylation status was compared with clinical findings and cytokine levels.ResultsOn the3rd and28th day of glucocorticoid treatment, SOCS1expression was negatively correlated with MELD score. IL-6and TNF-α levels were statistically lower while SOCS1transcription level was higher in survivals than non-survivals both in pre-and post-treatment ACHBLF patients. Methylation rate of SOCS1promoter in ACHBLF patients was higher than healthy controls determined by methylation-specific polymerase chain reaction. The mRNA level of SOCS1in methylated ones was significantly lower than that in unmethylated. IFN-y-responsive and STAT1-dependent genes expression was higher in survivals and was dramatically decreased with rising expression of SOCS1after glucocorticoid treatment. The mortality was significantly higher in methylated patients than those without methylation at the end of90-day follow-up. Furthermore, we found5in6survivals got SOCSl demethylated on the28th day after treatment, while the number was3in10non-survivals.ConclusionsIn conclusion, we researched the corticosteroids effect on SOCS1in ACHBLF patient with altered expression of mRNA and disparate methylation status. It revealed the effect of glucocorticoid on down-expression and demethylation of SOCS1in ACHBLF. These findings suggested that ACHBLF patients without SOCSl methylation may have a favorable response to corticosteroid treatment.