LPS诱导的急性炎性肝损伤中HIF-1α的表达

目的观察急性炎性肝损伤组织中缺氧诱导因子-1α(HIF-1α)的表达及其可能机制。方法采用卡介苗(BCG)配合LPS建立小鼠急性炎性肝损伤模型;肝组织石蜡切片HE染色法观察肝脏炎症反应情况;免疫组化染色法检测HIF-1α和VEGF的表达;ELISA检测小鼠血清中TNF-α的水平。结果炎症组小鼠HIF-1α、VEGF和TNF-α的表达均显著增加(均P<0.01)。结论急性炎性肝损伤时高表达HIF-1α及其靶基因VEGF,炎症组织中VEGF表达水平的上调与HIF-1α表达的增加可能相关,而HIF-1α表达的增加可能与TNF-α的水平升高有关。

当归制剂对脂多糖诱导的肝组织炎性损伤的影响及分子机制初探

目的 探讨应用当归制剂对脂多糖诱导的肝组织炎症反应的影响及其分子机制。方法 将ICR小鼠分为用药组、实验对照组及正常对照组 3组 ,采用脂多糖 (LPS)配合卡介苗 (BCG)注射法建立小鼠 (用药组和实验对照组 )肝脏炎性损伤模型 ,经腹腔给用药组小鼠注射当归制剂 ,给实验对照组注射等量生理盐水 ,连续给药 10d后 ,常规组织病理学观察 ,比较小鼠肝组织炎症反应情况。同时用逆转录 -聚合酶链反应 (RT -PCR)检测小鼠脾脏单个核细胞TNF -αmRNA表达的变化。结果 用药组小鼠肝脏的炎症反应明显弱于实验对照组 (P <0 .0 5 ) ;肝脏炎性损伤小鼠脾脏单个核细胞TNF -αmRNA的表达在注射LPS后 4h较正常对照组小鼠明显增加 (P <0 .0 1) ,在注射后 7h时达到峰值 ,而后有所下降 ;在注射LPS后 7h ,用药组小鼠TNF -αmRNA的表达与实验对照组相比 ,无显著差异。结论 当归制剂能显著抑制脂多糖诱导的肝组织炎症反应 ,明显减轻肝组织的炎性损伤 ,然而其主要抑制作用可能并非通过影响炎性介质TNF -αmRNA的表达来实现。

黄独素B诱导小鼠急性肝损伤及其机制

目的:观察黄药子中的二萜内酯类成分diosbulbin B(DB)诱导的急性肝毒性,并进一步探讨其对小鼠血清中炎性细胞因子和肝脏血红素加氧酶1(heme oxygenase-1,HO-1)表达的影响。方法:小鼠一次性灌胃给药DB(0,113,150,200 mg·kg-1),通过检测血清谷丙转氨酶(ALT),天冬氨酸转氨酶(AST),碱性磷酸酶(ALP)的活性来观察DB诱导的急性肝损伤,采用酶联免疫法(ELISA)检测血清中肿瘤坏死因子α(TNF-α),白细胞介素4(IL-4),白细胞介素1β(IL-1β)的含量,采用免疫印迹法(Western blot)观察HO-1的表达。结果:血清ALT,AST,ALP结果显示,DB 113 mg·kg-1灌胃后24 h,DB没有引起肝毒性;在150 mg·kg-1时,DB引起微弱的肝损伤;到200 mg·kg-1时,DB诱导明显的肝损伤。ELISA结果显示,DB能够剂量依赖性的增加血清中TNF-α的含量(P<0.05,P<0.01,P<0.001),DB(200 mg·kg-1)能够降低IL-4的含量(P<0.01),而不同剂量的DB对IL-1β的含量均没有明显影响。Western blot结果显示,DB(200 mg·kg-1)能够明显诱导肝组织中HO-1的表达(P<0.01)。结论:由TNF-α介导的炎性肝损伤以及氧化应激损伤可能是DB所诱导的急性肝毒性的主要原因。

Study progress on mechanism of severe acute pancreatitis complicated with hepatic injury

Study on the action mechanism of inflammatory mediators generated by the severe acute pancreatitis （SAP） in multiple organ injury is a hotspot in the surgical field. In clinical practice, the main complicated organ dysfunctions are shock, respiratory failure, renal failure, encephalopathy, with the rate of hepatic diseases being closely next to them. The hepatic injury caused by SAP cannot only aggravate the state of pancreatitis, but also develop into hepatic failure and cause patient death, lts complicated pathogenic mechanism is an obstacle in clinical treatment. Among many pathogenic factors, the changes of vasoactive substances, participation of inflammatory mediators as well as OFR （oxygen free radical）, endotoxin, etc. may play important roles in its progression.

Role of chemokines and their receptors in viral persistence and liver damage during chronic hepatitis C virus infection

Chemokines produced in the liver during hepatitis C virus(HCV) infection induce migration of activated T cells from the periphery to infected parenchyma.The milieu of chemokines secreted by infected hepatocytes is predominantly associated with the T-helper cell/Tc1 T cell(Th1/Tc1) response.These chemokines consist of CCL3(macrophage inflammatory protein-1α;MIP-1α),CCL4(MIP-1β),CCL5(regulated on activation normal T cell expressed and secreted;RANTES),CXCL10(interferon-γ-inducible protein-10;IP-10),CXCL11(interferon-inducible T-cell α chemoattractant;I-TAC),and CXCL9(monokine induced by interferon γ;Mig) and they recruit T cells expressing either CCR5 or CXCR3 chemokine receptors.Intrahepatic and peripheral blood levels of these chemokines are increased during chronic hepatitis C.The interaction between chemokines and their receptors is essential in recruiting HCV-specific T cells to control the infection.When the adaptive immune response fails in this task,non-specific T cells without the capacity to control the infection are also recruited to the liver,and these are ultimately responsible for the persistent hepatic damage.The modulation of chemokine receptor expression and chemokine secretion could be a viral escape mechanism to avoid specific T cell migration to the liver during the early phase of infection,and to maintain liver viability during the chronic phase,by impairing non-specific T cell migration.Some chemokines and their receptors correlate with liver damage,and CXCL10(IP-10) and CXCR3 levels have shown a clinical utility as predictors of treatment response outcome.The regulation of chemokines and their receptors could be a future potential therapeutic target to decrease liver inflammation and to increase specific T cell migration to the infected liver.

Involvement of autophagy in alcoholic liver injury and hepatitis C pathogenesis

This review describes the principal pathways of macroautophagy (i.e. autophagy), microautophagy and chaperone-mediated autophagy as they are currently known to occur in mammalian cells. Because of its crucial role as an accessory digestive organ, the liver has a particularly robust autophagic activity that is sensitive to changes in plasma and dietary components. Ethanol consumption causes major changes in hepatic protein and lipid metabolism and both are regulated by autophagy, which is significantly affected by hepatic ethanol metabolism. Ethanol exposure enhances autophagosome formation in liver cells, but suppresses lysosome function. Excessive ethanol consumption synergizes with hepatitis C virus (HCV) to exacerbate liver injury, as alcohol-consuming HCV patients frequently have a longer course of infection and more severe manifestations of chronic hepatitis than abstinent HCV patients. Alcohol-elicited exacerbation of HCV infection pathogenesis is related to modulation by ethanol metabolism of HCV replication. Additionally, as part of this mechanism, autophagic proteins have been shown to regulate viral (HCV) replication and their intracel-lular accumulation. Because ethanol induces autophagosome expression, enhanced levels of autophagic proteins may enhance HCV infectivity in liver cells of alcoholics and heavy drinkers.

Association between TRAIL expression on peripheral blood lymphocytes and liver damage in chronic hepatitis B

AIM:To explore a novel mechanism for tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), upregulation of CD4+ and CD8+T lymphocytes participating in the patho-physiological process of chronic hepatitis B (CHB). METHODS: The levels of serum soluble TRAIL (sTRAIL), serum IFN-γ and membrane-bound TRAIL expression on peripheral leucocytes from 58 CHB patients were examined by ELISA and flow cytometry respectively. The levels of TRAIL were compared with the baseline levels of 17 healthy controls, and correlation analysis was performed between ALT, TBIL, PT, morphological change in hepatic tissues, and serum IFN-γ. RESULTS: The results showed that TRAIL levels on membranes of CD4+, CD8+ T cells in CHB patients were much higher than those in healthy controls (P<0.001), and were correlated with serum TBIL (r=0.354, P= 0.008 for CD4+ and r= 0.522, P= 0.000 for CD8+, respectively), ALT (r= 0.393, P= 0.003 for CD8+), PT (r = 0.385, P = 0.004 for CD8+) and serum IFN-y level (r = 0.302, P= 0.011 for CD4+ and r= 0.307, P= 0.009 for CD8+). On the contrary to membrane-bound TRAIL expression, serum level of sTRAIL was not correlated with that of TBIL and PT, though it was higher than that of the normal population and was positively correlated with serum HBeAg expression (r= 0.695, P = 0.001). CONCLUSION: The expression level of TRAIL on the membrane of lymphocytes was upregulated and associated with the liver injury in CHB patients. These findings suggest that upregulation of TRAIL expression may be induced by virus antigen and inflammatory cytokine IFN-γ.

Pancreatic involvement in chronic viral hepatitis

AIM: To elucidate the frequency and characteristics of pancreatic disorders in the course of chronic viral hepatitis. METHODS: We prospectively assessed the serum pancreatic enzyme levels and imaging findings in patients with chronic viral hepatitis and healthy control subjects. RESULTS: Serum amylase (t-Amy), salivary amylase (s-Amy), pancreatic amylase (p-Amy) and serum lipase levels were higher in hepatitis patients in comparison to control subjects. However, in asymptomatic viral carriers, only the serum t-Amy levels were higher than those of the controls. The levels of each enzyme rose with the progression of liver disease in patients with hepatitis B or C; whereas the levels of each enzyme within the same clinical stage of the disease did not differ between patients diagnosed with either hepatitis B or hepatitis C virus. Imaging findings demonstrated chronic pancreatitis in only 1 out of 202 patients (0.5%).CONCLUSION: Our data suggest that serum levels of pancreatic enzymes increase with the progression of liver disease in patients diagnosed with viral hepatitis. Pancreatic disease, asymptomatic in most cases, may represent an extrahepatic manifestation of chronic viral hepatitis.

Acute transient hepatocellular injury in cholelithiasis and cholecystitis without evidence of choledocholithiasis

AIM： To investigate acute transient hepatocellular injury in patients with cholelithiasis and cholecystitis but no evidence of choledocholithiasis.METHODS： The medical records of patients with cholelithiasis who underwent cholecystectomy between July 2003 and June 2007 were retrospectively reviewed. Imaging studies to detect common bile duct （CBD） stones were performed in 186 patients, who constituted the study population. Biochemical liver tests before and after surgery, and with the presence or absence of CBD stones were analyzed.RESULTS： In 96 patients with cholelithiasis and cholecystitis without evidence of CBD stones, 49 （51.0%） had an alanine aminotransferase level elevated to 2-3 times the upper limit of normal, and 40 （41.2%） had an elevated aspartate aminotransferase level. Similar manifestations of hepatocellular injury were, as would be expected, even more obvious in the 90 patients with CBD stones. These markers of hepatocellular injury resolved almost completely within 2 wk to 1 mo after cholecystectomy. Compared to 59 patients with histologically less severe cholecystitisin the group undergoing urgent surgery （total 74 patients）, the 15 patients with a gangrenous gallbladder had a higher mean level of total bilirubin （2.14 ± 1.27 mg/dL vs 2.66 ± 2.97 mg/dL, P 〈 0.001） and white cell count （9480 ± 4681/μL vs 12840 ± 5273/μL, P = 0.018）.CONCLUSION： Acute hepatocellular injury in cholelithiasis and cholecystitis without choledocholithiasis is mild and transient. Hyperbilirubinemia and leukocytosis may predict severe inflammatory changes in the gallbladder.

Study on protecting effects of Baicalin and Octreotide on hepatic injury in rats with severe acute pancreatitis

AIM: To investigate the protective effects and mechanisms of Baicalin and Octreotide on hepatic injury in rats with severe acute pancreatitis (SAP). METHODS: The SAP rat models were prepared and randomly assigned to the model control group, Baicalin treated group, and Octreotide treated group while other healthy rats were assigned to the sham-operated group. Rat mortality, levels of ALT, AST, liver and pancreas pathological changes in all groups were observed at 3, 6 and 12 h after operation. Tissue microarray (TMA) sections of hepatic tissue were prepared to observe expression levels of Bax, Bcl-2 protein and Caspase-3, and changes of apoptotic indexes.RESULTS: Rat survival at 12 h, expression levels of Bax, Caspase-3 protein and apoptotic indexes of liver were all significantly higher in treated groups than in model control group. While the liver and pancreas pathological scores, contents of ALT, AST, and expression levels of Bcl-2 protein were all lower in treated groups than in the model control group. CONCLUSION: Both Baicalin and Octreotide can protect rats with SAP by decreasing the contents of ALT, AST and expression levels of Bcl-2 protein, and improving the expression levels of Bax protein, Caspase-3 protein, and inducing apoptosis.

Expression of macrophage inflammatory protein-1αin Kupffer cells following liver ischemia or reperfusion injury in rats

AIM： To explore the expression of macrophage inflammatory protein-1α （MIP-1α） in Kupffer cells （KCs） following liver ischemia/reperfusion injury IRI in rats. METHODS： Forty male SD rats were divided randomly into five groups. A model of partial warm ischemia/ reperfusion injury in the rat liver was established. KCs were isolated and incubated one hour, six hours, 12 h, and 24 h after the reperfusion. Tumor necrosis factor alpha （TNF-α） and interleukin-lbeta （IL-1β） in the supernatants were measured by ELISA. MIP-1α in KCs was detected by immunocytochemical and RT-PCR. RESULTS： No or few MIP-1α protein and mRNA were expressed in the KCs of the control group. Its expression in the IRI group had a significant increase after the reperfusion （P 〈 0.05）, which was contrary to the control group. CONCLUSION： The active behavior of the MIP-1α gene in KCs following liver ischemia/reperfusion injury is assumed to be one of the major causes for the hepatic ischemia/reperfusion injury.

Mutations in hepatitis B virus core regions correlate with hepatocellular injury in Chinese patients with chronic hepatitis B

AIM: To elucidate the relationship between the frequency of core mutations and the clinical activity of hepatitis B virus (HBV)-related liver disease and to characterize the amino acid changes in the core region of HBV.METHODS: We studied 17 Chinese patients with chronic hepatitis B according to their clinical courses and patterns of the entire core region of HBV.RESULTS: Amino acid changes often appeared in the HBV core region of the HBV gene in patients with high values of alanine aminotransferase (ALT) or with the seroconversion from HbeAg to anti-HBe. The HBV core region with amino acid changes had high frequency sites that corresponded to HLA Ⅰ/Ⅱ restricted recognition epitopes reported by some investigators.CONCLUSION: The core amino acid changes of this study occur due to influence of host immune system. The presence of mutations in the HBV core region seems to be important for predicting the clinical activity of hepatitis B in Chinese patients.

Serum levels of microRNAs can specifically predict liver injury of chronic hepatitis B

AIM： To investigate whether circulating microRNAs （miRNAs） can serve as molecular markers to predict liver injury resulted from chronic hepatitis B （CHB）. METHODS： The profiles of serum miRNA expression were first generated with serum samples collected from 10 patients with CHB and 10 healthy donors （Ctrls） by microarray analysis. The levels of several miRNAs were further quantitated by real-time reverse transcription polymerase chain reaction with serum samples from another 24 CHB patients and 24 Ctrls. Serum samples of 20 patients with nonalcohlic steatohepatitis （NASH） were also included for comparison. The comparison in the levels of miRNAs between groups （CHB, NASH and Ctrl） was analyzed with Mann-Whitney U-test. The cor- relation between miRNAs and clinical pathoparameters was analyzed using Spearman correlation analysis or canonical correlation analysis. The receiver-operator characteristic （ROC） curves were also generated to de- termine the specificity and sensitivity of each individual miRNA in distinguishing patients with CriB from Ctrls. RESULTS： miRNA profile analysis showed that 34 miR- NAs were differentially expressed between CriB and Ctrl subjects, in which 12 were up-regulated and 22 down-regulated in CriB subject （fold change 〉 2.0 and P 〈 0.01）. The median levels of miR-122, -572, -575 and -638 were significantly higher （P 〈 1.00 × 10-5） while miR-744 significantly lower （P 〈 1.0× 10-6） in Crib compared with the Ctrl. The levels of miR-122, -572 and -638 were also higher （P 〈 1.00×10-3） while the level of miR-744 lower in CriB （P 〈 0.05） than in NASH, although the difference between them was not as significant as that between CHB and Ctrl. ROC curve analysis revealed that the levels of miR-122, -572, -575, -638 and -744 in serum were sensitive and specific enough to distinguish CriB, NASH and Ctrl. Multivariate analysis further showed that the levels of these miRNAs were correlated with the liver function parameters. Most significantly, it was the scatter plot of principal component with the levels of these miRNAs, but not the parameters of liver function, which clearly distinguished CriB, NASH and Ctrl subjects. CONCLUSION： Serum levels of miR-122, -572, -575, -638 and -744 are deregulated in patients with CHB or NASH. The levels of these miRNAs may serve as po- tential biomarkers for liver injury caused by CHB and NASH.

Replication of hepatitis B virus in primary duck hepatocytes transfected with linear viral DNA

AIM: To explore the expression and replication of hepatitis B virus (HBV) DNA in primary duck hepatocytes (PDHs).METHODS: Complete HBV genome was transfected into PDHs by electroporation (transfected group, 1.19×1012copies of linear HBV DNA/1×107 PDHs). After 1-5 d of transfection, HBsAg and HBeAg in the supernatant and lysate of PDHs were measured with the IMX System.Meanwhile, replicative intermediates of HBV DNA were analyzed by Southern blotting and Dot blotting. PDHs electroporated were used as control group.RESULTS: HBsAg in the hepatocyte lysates of transfected group was 15.24 (1 d), 14.55 (3 d) and 5.13 (5 d; P/N values, positive≥2.1) respectively. HBeAg was negative (＜2.1). Both HBsAg and HBeAg were negative in the supernatant of transfected group. Dot blotting revealed that HBV DNA was strongly positive in the transfected group and negative in the control group. Southern blot analysis of intracellular total DNA indicated that there were relaxed circular (rc DNA), covalently closed circular (ccc DNA), and single-stranded (ss DNA) HBV DNA replicative intermediates in the transfected group, there was no integrated HBV DNA in the cellular genome. These parameters were negative in control group.CONCLUSION: Expression and replication of HBV genes can occur in hepatocytes from non-mammalian species.HBV replication has no critical species-specificity, and yet hepatic-specific regulating factors in hepatocytes may be essential for viral replication.