Study on the injury effects and mechanisms of circulating histones on the hepatocytes of patients with hepatitis B virus-related liver failure / 中华传染病杂志

ABSTRACT

Objective To investigate the injury effects and mechanisms of circulating histones on the hepatocytes in patients with hepatitis B virus (HBV )-related liver failure (HBV-LF) .Methods Serum samples from patients with HBV-LF were collected . The levels of serum histone H3 , histone H4 , prothrombin activity (PTA ) ,total bilirubin (TBil) ,creatinine (Cr) and international normalized ratio (INR) of the patients were measured .Model for end-stage liver disease (MELD) score was calculated in the patients .The serum levels of histones were compared between patients and the healthy volunteers . The correlation of histones with the MELD score and PTA was analyzed .The human liver cell line L-02 cells were cultured and treated with the serum of patients or L-02 cellular lysate supernatant preincubated with or without anti-histone H3 and H4 antibodies .The cellular morphology and rate of apoptosis were observed .Intracellular calcium ion concentration and Caspase-3 activity were detected in the cultured L-02 cells treated with histones .Mean of two independent samples was compared using t tests .Relationship between histones and the MELD score or PTA was conducted using Spearman correlation analysis .Results The levels of serum histones in the patients with HBV-LF were much higher than those in the healthy volunteers (H3[5 390 .3 ± 1 032 .0] μg/mL vs [42 .7 ± 12 .8] μg/mL , t = 32 .76 , P < 0 .01 ; H4[4 205 .1 ± 662 .3] μg/mL vs [40 .3 ± 14 .6] μg/mL ,t = 39 .74 , P< 0 .01) .In addition ,serum histones (H3/H4) levels in patients were negatively correlated with serum PTA (r= - 0 .325 ,P= 0 .038 and r =- 0 .572 ,P= 0 .028 ,respectively) ,but positively correlated with the MELD score (r= 0 .359 ,P= 0 .021 and r = 0 .568 , P = 0 .007 , respectively ) . Both serum of patients with HBV-LF and L-02 lysate supernatant were toxic to cultured L-02 cells .The injury effect was inhibited by anti-histone antibodies ([9 .3 ± 1 .5]% vs [14 .3 ± 0 .6]% , t = 4 .259 , P= 0 .02) .L-02 cells treated with calf thymus histone were cultured for 4 h . Cellular toxicity of histones resulted in Caspase-3 activation . The effect was inhibited by anti-histone antibodies ([3 .5 ± 0 .5]% vs [5 .2 ± 0 .6]% ,t= 4 .243 ,P= 0 .02) .Conclusion The elevated circulating histones in the patients with HBV-LF may aggravate the liver damage .