Adiponectin,a key adipokine in obesity related liver diseases

Non-alcoholic fatty liver disease (NAFLD) comprising hepatic steatosis,non-alcoholic steatohepatitis (NASH),and progressive liver fibrosis is considered the most common liver disease in western countries.Fatty liver is more prevalent in overweight than normal-weight people and liver fat positively correlates with hepatic insulin resistance.Hepatic steatosis is regarded as a benign stage of NAFLD but may progress to NASH in a subgroup of patients.Besides liver biopsy no diagnostic tools to identify patients with NASH are available,and no effective treatment has been established.Visceral obesity is a main risk factor for NAFLD and inappropriate storage of triglycerides in adipocytes and higher concentrations of free fatty acids may add to increased hepatic lipid storage,insulin resistance,and progressive liver damage.Most of the adipose tissue-derived proteins are elevated in obesity and may contribute to systemic inflammation and liver damage.Adiponectin is highly abundant in human serum but its levels are reduced in obesity and are even lower in patients with hepatic steatosis or NASH.Adiponectin antagonizes excess lipid storage in the liver and protects from inflammation and fibrosis.This review aims to give a short survey on NAFLD and the hepatoprotective effects of adiponectin.

Liver-specific gene expression in mesenchymal stem cells is induced by liver cells

AIM： The origin of putative liver cells from distinct bone marrow stem cells, e.g. hematopoietic stem cells or multipotent adult progenitor cells was found in recent in vitro studies. Cell culture experiments revealed a key role of growth factors for the induction of liver-specific genes in stern cell cultures. We investigated the potential of rat mesenchymal stem cells （MSC） from bone marrow to differentiate into hepatocytic cells in vitro. Furthermore, we assessed the influence of cocultured liver cells on induction of liver-specific gene expression. METHODS： Mesenchymal stem cells were marked with green fluorescent protein （GFP） by retroviral gene transduction. Clonal marked MSC were either cultured under liver stimulating conditions using fibronectin-coated culture dishes and medium supplemented with SCF, HGF, EGF, and FGF-4 alone, or in presence of freshly isolated rat liver cells. Cells in cocultures were harvested and GFP＋ or GFP- cells were separated using fluorescence activated cell sorting. RT-PCR analysis for the stem cell marker Thyl and the hepatocytic markers CK-18, albumin, CK-19, and AFP was performed in the different cell populations. RESULTS： Under the specified culture conditions, rat MSC cocultured with liver cells expressed albumin-, CK-18, CK-19, and AFP-RNA over 3 weeks, whereas MSC cultured alone did not show liver specific gene expression, CONCLUSION： The results indicate that （1） rat MSC from bone marrow can differentiate towards hepatocytic lineage in vitro, and （2） that the microenvironment plays a decisive role for the induction of hepatic differentiation of rMSC.

Primary sclerosing cholangitis, autoimmune hepatitis and overlap syndromes in inflammatory bowel disease

Primary sclerosing cholangitis （PSC） is a chronic progressive disorder of unknown aetiology characterised by chronic inflammation and stricture formation of the biliary tree. Symptoms include itch and lethargy and in advanced cases cholangitis and end-stage liver disease, however increasing numbers of asymptomatic individuals are being identified. The disease is rare in the general population but is strongly associated with inflammatory bowel disease （IBD） affecting up to 5% of patients with Ulcerative Colitis, with a slightly lower prevalence （up to 3.6%） in Crohns disease. The strength of this association means that the vast majority （ 〉 90%） of patients with PSC also have IBD, although many may have only mild gastro-intestinal symptoms. Usually IBD presents before PSC, although vice-versa can occur and the onset of both conditions can be separated in some cases by many years. Mean age of diagnosis of PSC is in the fitch decade of life with a strong male predominance. Risk is increased in those with a family history of PSC, suggesting a genetic predisposition and the disease is almost exclusive to non-smokers. The ulcerative colitis associated with PSC is characteristically mild, runs a quiescent course, is associated with rectal sparing, more severe right sided disease, backwash ilieitis and has a high risk of pouchitis post-colectomy. Most worrisome is the high risk of colorectal malignancy which necessitates routine colonoscopic surveillance. Cholangiocarcinoma is also a frequent complication of PSC with a 10%-15% lifetime risk of developing this condition. Treatment with high dose ursodeoxycholic acid offers some chemoprotective effects against colorectal malignancy and may decrease symptoms, biochemical and histological progression of liver disease. Small duct PSC patients characteristically have normal cholangiography, and liver biopsy is required for diagnosis, it appears to have a more favourable prognosis. Autoimmune Hepatitis （AIH） is also more prevalent in patients with IBD, with up to 16% of patients with Autoimmune Hepatitis also having ulcerative colitis. A small subgroup of patients have a AIH-PSC overlap syndrome and the management of these patients depends on liver histology, serum IgM levels, autoantibodies, degree of biochemical cholestasis and cholangiography as some of these patients may respond to immunosupression.

Fibrinogen-like protein 2 fibroleukin expression and its correlation with disease progression in murine hepatitis virus type 3-induced fulminant hepatitis and in patients with severe viral hepatitis B

AIM： To evaluate the expression of fibrinogenlike protein 2 （fgl2） and its correlation with disease progression in both mice and patients with severe viral hepatitis. METHODS： Balb/cJ or A/J mice were infected intraperitoneally （ip） with 100 PFU of murine hepatitis virus type 3 （MHV-3）, liver and serum were harvested at 24, 48, and 72 h post infection for further use. Liver tissues were obtained from 23 patients with severe acute chronic （AOC） hepatitis B and 13 patients with mild chronic hepatitis B. Fourteen patients with mild chronic hepatitis B with cirrhosis and 4 liver donors served as normal controls. In addition, peripheral blood mononuciear cells （PBMC） were isolated from 30 patients （unpaired） with severe AOC hepatitis B and 10 healthy volunteers as controls. Procoagulant activity representing functional prothrombinase activity in PBMC and white blood cells was also assayed. A polyclonal antibody against fgl2 was used to detect the expression of both mouse and human fgl2 protein in liver samples as well as in PBMC by immunohistochemistry staining in a separate set of studies. Alanine aminotransferase （ALT） and total bilirubin （TBil） in serum were measured to assess the severity of liver injury.RESULTS： Histological changes were found in liver sections 12-24 h post MHV-3 infection in Balb/cJ mice. In association with changes in liver histology, marked elevations in serum ALT and TBil were observed. House fgl2 （mfgl2） protein was detected in the endothelium of intrahepatic veins and hepatic sinusoids within the liver 24 h after MHV-3 infection. Liver tissues from the patients with severe AOC hepatitis B had classical pathological features of acute necroinflammation. Human fgl2 （hfgl2） was detected in 21 of 23 patients （91.30%） with severe AOC hepatitis B, while only 1 of 13 patients （7.69%） with mild chronic hepatitis B and cirrhosis had hfgl2 mRNA or protein expression. Twenty-eight of thirty patients （93.33%） with severe AOC hepatitis B and 1 of 10 with mild chronic hepatitis B had detectable hfgl2 expression in PBMC. No hfgl2 expression was found either in the liver tissue or in the PBMC from normal donors. There was a positive correlation between hfgl2 expression and the severity of the liver disease as indicated by the levels of TBil. PCA significantly increased in PBMC in patients with severe AOC hepatitis B. CONCLUSION： The molecular and cellular results reported here in both mice and patients with severe viral hepatitis suggest that virus-induced hfgl2 prothrombinase/fibroleukin expression and the coagulation activity associated with the encoded fgl2 protein play a pivotal role in initiating severe hepatitis. The measurement of hfgl2/fibroleukin expression in PBMC may serve as a useful marker to monitor the severity of AOC hepatitis B and a target for therapeutic intervention.

Assessment of correlation between serum titers of hepatitis c virus and severity of liver disease

AIM:The significance of hepatitis C virus (HCV) serum titers has been examined in several clinical situations. There is much evidence that patients with a lower viral load have better response rates to anti-viral therapy compared to those with higher levels.Moreover,a direct association has been observed between serum titers of HCV and transmission rates of the virus.The aim of the present study was to determine if there was any correlation between HCV viral load and the severity of liver disease. METHODS:Fifty patients with HCV infection were included in the study.These comprised of 34 subjects with a history of alcohol use and 16 non-alcoholics.Quantitative serum HCV RNA assay was carried out using the branched DNA (bDNA) technique.Linear regression analysis was performed between serum viral titers and liver tests.In addition,for the purpose of comparison,the subjects were divided into two groups:those with low viral liters (≤50 genome mEq/mL) and high titers (>50 mEq/mL). RESULTS:All subjects were men,with a mean±SD age of 47±7.8 years.The mean HCV RNA level in the blood was 76.3×10~5±109.1 genome equivalents/mL.There was no correlation between HCV RNA levels and age of the patients (r=0.181),and the history or amount (g/d) of alcohol consumption (r=0.07).Furthermore,no correlation was observed between serum HCV RNA levels and the severity of liver disease as judged by the values of serum albumin (r=0.175),bilirubin (r=0.217),ALT (r=0.06) and AST (r=0.004) levels.Similarly,no significant difference was observed between patients with low viral titers and high liters with respect to any of the parameters. CONCLUSION:Our results indicate that the severity of liver disease is independent of serum levels of hepatitis C virus.These findings are important since they have a direct impact on the current debate regarding the role of direct cytopathic effect of hepatitis C virus versus immune-mediated injury in the pathogenesis of HCV-related liver damage.

Non invasive fibrosis biomarkers reduce but not substitute the need for liver biopsy

Chronic liver diseases are very common worldwide, particularly those linked to viral hepatitis and to alcoholic and non-alcoholic fatty liver. Their natural history is variable and long-term evolution differs in individual patients. Optimised clinical management of compensated chronic liver diseases requires precise definition of the stage of liver fibrosis, the main determinant of prognosis and of most therapeutic decisions. Liver biopsy is the gold standard for assessment of hepatic fibrosis. However, it is invasive with possible complications, costly and prone to sampling errors. Many non-invasive markers of liver fibrosis have been recently proposed and assessed in the clinical setting as surrogates of liver biopsy. Direct markers are based on biochemical parameters directly linked to fibrogenesis while indirect markers use simple or more sophisticated parameters that correlate with liver fibrosis stages. Non-invasive markers of liver fibrosis have been tested in different forms of chronic liver disease and showed variable diagnostic performance, but accuracy rarely was above 75%-80%. Better results were obtained when markers were combined. On this line, we have recently proposed a set of algorithms that combine sequentially indirect non-invasive markers of liver fibrosis, reaching 90%-95% diagnostic accuracy with significant reduction in the need for liver biopsy. Based on available evidence, it can be anticipated that non-invasive markers of liver fibrosis and their combined use will soon become a most useful tool in the clinical management of many forms of chronic liver disease. However, their implementation is expected to reduce, but not to completely eliminate, the need for liver biopsy.

Biochemical mechanisms in drug-induced liver injury:Certainties and doubts

Drug-induced liver injury is a significant and still unresolved clinical problem. Limitations to knowledge about the mechanisms of toxicity render incomplete the detection of hepatotoxic potential during preclinical development. Several xenobiotics are lipophilic substances and their transformation into hydrophilic compounds by the cytochrome P-450 system results in production of toxic metabolites. Aging, preexisting liver disease, enzyme induction or inhibition, genetic variances, local 02 supply and, above all, the intrinsic molecular properties of the drug may affect this process. Necrotic death follows antioxidant consumption and oxidation of intracellular proteins, which determine increased permeability of mitochondrial membranes, loss of potential, decreased ATP synthesis, inhibition of Ca^2＋-dependent ATPase, reduced capability to sequester Ca^2＋ within mitochondria, and membrane bleb formation. Conversely, activation of nucleases and energetic participation of mitochondria are the main intracellular mechanisms that lead to apoptosis. Non-parenchymal hepatic cells are inducers of hepatocellular injury and targets for damage. Activation of the immune system promotes idiosyncratic reactions that result in hepatic necrosis or cholestasis, in which different HLA genotypes might play a major role. This review focuses on current knowledge of the mechanisms of drug-induced liver injury and recent advances on newly discovered mechanisms of liver damage. Future perspectives including new frontiers for research are discussed.

Role of cytokines and chemokines in non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) includes a variety of histological conditions (ranging from liver steatosis and steatohepatitis, to fibrosis and hepatocarcinoma) that are characterized by an increased fat content within the liver. The accumulation/deposition of fat within the liver is essential for diagnosis of NAFLD and might be associated with alterations in the hepatic and systemic inflammatory state. Although it is still unclear if each histological entity represents a different disease or rather steps of the same disease, inflammatory processes in NAFLD might influence its pathophysiology and prognosis. In particular, non-alcoholic steatohepatitis (the most inflamed condition in NAFLDs, which more frequently evolves towards chronic and serious liver diseases) is characterized by a marked activation of inflammatory cells and the upregulation of several soluble inflammatory mediators. Among several mediators, cytokines and chemokines might play a pivotal active role in NAFLD and are considered as potential therapeutic targets. In this review, we will update evidence from both basic research and clinical studies on the potential role of cytokines and chemokines in the pathophysiology of NAFLD.

Bile acids:Chemistry,physiology,and pathophysiology

The family of bile acids includes a group of molecular species of acidic steroids with very peculiar physical-chemical and biological characteristics.They are synthesized by the liver from cholesterol through several complementary pathways that are controlled by mechanisms involving finetuning by the levels of certain bile acid species.Although their best-known role is their participation in the digestion and absorption of fat,they also play an important role in several other physiological processes.Thus,genetic abnormalities accounting for alterations in their synthesis,biotransformation and/or transport may result in severe alterations,even leading to lethal situations for which the sole therapeutic option may be liver transplantation.Moreover,the increased levels of bile acids reached during cholestatic liver diseases are known to induce oxidative stress and apoptosis,resulting in damage to the liver parenchyma and,eventually,extrahepatic tissues.When this occurs during pregnancy,the outcome of gestation may be challenged.In contrast,the physical-chemical and biological properties of these compounds have been used as the bases for the development of drugs and as pharmaceutical tools for the delivery of active agents.

Emerging role of microRNAs in liver diseases

MicroRNAs are a class of small non-coding RNAs that are found in plants, animals, and some viruses. They modulate the gene function at the post-transcriptional level and act as a fine tuner of various processes, such as development, proliferation, cell signaling, and apopto-sis. They are associated with different types and stages of cancer. Recent studies have shown the involvement of microRNAs in liver diseases caused by various factors, such as Hepatitis C, Hepatitis B, metabolic disorders, and by drug abuse. This review highlights the role of microRNAs in liver diseases and their potential use as therapeutic molecules.

MicroRNA signatures in liver diseases

MicroRNAs (miRNAs) are an emerging class of highly conserved non-coding small RNAs that regulate gene expression at the post-transcriptional level. It is now clear that miRNAs can potentially regulate every aspect of cellular activity, including differentiation and development, metabolism, proliferation, apoptotic cell death, viral infection and tumorigenesis. Recent studies provide clear evidence that miRNAs are abundant in the liver and modulate a diverse spectrum of liver functions. Deregulation of miRNA expression may be a key pathogenetic factor in many liver diseases including viral hepatitis, hepatocellular cancer and polycystic liver diseases. A clearer understanding of the mechanisms involved in miRNA deregulation will offer new diagnostic and therapeutic strategies to treat liver diseases. Moreover, better understanding of miRNA regulation and identification of tissue-specific miRNA targets employing transgenic/knockout models and/or modulating oligonucleotides will improve our knowledge of liver physiology and diseases.

Drug-induced liver injury:Is it somehow foreseeable?

The classic view on the pathogenesis of drug-induced liver injury is that the so-called parent compounds are made hepatotoxic by metabolism (formation of neosubstances that react abnormally), mainly by cytochromes P-450 (CYP), with further pathways, such as mitochondrial dysfunction and apoptosis, also playing a role. Risk factors for drug-induced liver injury include concomitant hepatic diseases, age and genetic polymorphisms of CYP. However, some susceptibility can today be predicted before drug administration, working on the common substrate, by phenotyping and genotyping studies and by taking in consideration patients' health status. Physicians should always think of this adverse effect in the absence of other clear hepatic disease. Ethical and legal problems towards operators in the health care system are always matters to consider.

Chronic liver disease questionnaire:Translation and validation in Thais

AIM:Quality of life (QOL) is a concept that incorporates many aspects of life beyond“health”.The chronic liver disease questionnaire (CLDQ) was developed to evaluate the impact of chronic liver diseases (CLD) on QOL.The objectives of this study were to translate and validate a liver specific questionnaire,the CLDQ. METHODS:The CLDQ was formally translated from the original version to Thai language with permission.The translation process included forward translation,back translation,cross-cultural adaptation and a pretest.Reliability and validity of the translated version was examined in CLD patients.Enrolled subjects included CLD and normal subjects with age- and sex-matched.Collected data were demography, physical findings and biochemical tests.All subjects were asked to complete the translated versions of CLDQ and SF- 36,which was previously validated.Cronbach's alpha and test-retest were performed for reliability analysis.One-way Anova or non-parametric method was used to determine discriminant validity.Speerman's rank correlation was used to assess convergent validity.P-value<0.05 was considered statistically significant. RESULTS:A total of 200 subjects were recruited into the study,with 150 CLD and 50 normal subjects.Mean ages (SD) were 47.3(11.7) and 49.1(8.5) years,respectively.The number of chronic hepatitis:cirrhosis was 76:74,and the ratio of cirrhotic patients classified as Child A:B:C was 37 (50%):26(35%):11(15%).Cronbach's alpha of the overall CLDQ scores was 0.96 and of all domains were higher than 0.93.Item-total correlation was>0.45.Test-retest reliability done at 1 to 4 wk apart was 0.88 for the average CLDQ score and from 0.68 to 0.90 for domain scores.The CLDQ was found to have discriminant validity.The highest scores of CLDQ domains were in the normal group,scores were lower in the compensated group and lowest in the decompensated group.The significant correlation between domains of the CLDQ and SF-36 was found.The average CLDQ score was strongly correlated with the general health domain of SF-36.(P=0.69:P=0.01). CONCLUSION:The translated CLDQ is valid and applicable in Thais with CLD.CLDQ reveals that QOL in these patients is lower than that in normal population.QOL is more impaired in advanced stage of CLD.

Treatment for liver metastases from breast cancer: Results and prognostic factors

AIM: Liver metastases from breast cancer (BCLM) are associated with poor prognosis. Cytotoxic chemotherapy can result in regression of tumor lesions and a decrease in symptoms. Available data, in the literature, also suggest a subgroup of patients may benefit from surgery, but few talked about transcatheter arterial chemoembolization (TACE). We report the results of TACE and systemic chemotherapy for patients with liver metastases from breast cancer and evaluate the prognostic factors. METHODS: Forty-eight patients with liver metastases, from proved breast primary cancer were treated with TACE or systemic chemotherapy between January 1995 and December 2000. Treatment results were assessed according to WHO criteria, along with analysis of prognostic factors for survival using Cox regression model. RESULTS: The median follow-up was 28 mo (1-72 mo). Response rates were calculated for the TACE group and chemotherapy group, being 35.7% and 7.1%, respectively. The difference was significant. The one-, two- and three-year Survival rates for the TACE group were 63.04%, 30.35%, and 13.01%, and those for the systemic chemotherapy group were 33.88%, 11.29%, and 0%. According to univariate analysis, variables significantly associated with survival were the lymph node status of the primary cancer, the clinical stage of liver metastases, the Child-Pugh grade, loss of weight. Other factors such as age, the intervals between the primary to the metastases, the maximal diameter of the liver metastases, the number of liver metastases, extrahepatic metastasis showed no prognostic significances. These factors mentioned above such as the lymph node status of the primary cancer, the clinical stage of liver metastases, the Child-Pugh grade, loss of weight were also independent factors in multivariate analysis. CONCLUSION: TACE treatment of liver metastases from breast cancer may prolong survival in certain patients. This approach offers new promise for the curative treatment of the patients with metastatic breast cancer.

P16 gene hypermethylation and hepatocellular carcinoma:A systematic review and meta-analysis

AIM:To quantitatively investigate the effect of p16 hypermethylation on hepatocellular carcinoma (HCC) and hepatocirrhosis using a meta-analysis of available casecontrol studies.METHODS:Previous studies have primarily evaluated the incidence of p16 hypermethylation in HCC and corresponding control groups,and compared the incidence of p16 hypermethylation in tumor tissues,pericancer liver tissues,normal liver tissues and non-tumor liver tissues with that in other diseases.Data regarding publication information,study characteristics,and incidence of p16 hypermethylation in both groups were collected from these studies and summarized.RESULTS:Fifteen studies,including 744 cases of HCC and 645 non-tumor cases,were identified for meta-analysis.Statistically significant odds ratios (ORs) of p16 hypermethylation were obtained from tumor tissues and non-tumorous liver tissues of HCC patients (OR 7.04,95% CI:3.87%-12.78%,P < 0.0001),tumor tissues of HCC patients and healthy liver tissues of patients with other diseases (OR 12.17,95% CI:6.64%-22.31%,P < 0.0001),tumor tissues of HCC patients and liver tissues of patients with non-tumorous liver diseases (OR 6.82,95% CI:4.31%-10.79%,P < 0.0001),and cirrhotic liver tissues and non-cirrhotic liver tissues (OR 4.96,95% CI:1.45%-16.96%,P=0.01).The pooled analysis showed significantly increased ORs of p16 hypermethylation (OR 6.98,95% CI:4.64%-10.49%,P < 0.001) from HCC tissues and cirrhotic tissues.CONCLUSION:P16 hypermethylation induces the inactivation of p16 gene,plays an important role in hepatocarcinogenesis,and is associated with an increased risk of HCC and liver cirrhosis.

Novel interactions of mitochondria and reactive oxygen/nitrogen species in alcohol mediated liver disease

Mitochondrial dysfunction is known to be a contributing factor to a number of diseases including chronic alcohol induced liver injury. While there is a detailed understanding of the metabolic pathways and proteins of the liver mitochondrion, little is known regarding how changes in the mitochondrial proteome may contribute to the development of hepatic pathologies. Emerging evidence indicates that reactive oxygen and nitrogen species disrupt mitochondrial function through post-translational modifications to the mitochondrial proteome. Indeed, various new affinity labeling reagents are available to test the hypothesis that post-translational modification of proteins by reactive species contributes to mitochondrial dysfunction and alcoholic fatty liver disease. Specialized proteomic techniques are also now available, which allow for identification of defects in the assembly of multi-protein complexes in mitochondria and the resolution of the highly hydrophobic proteins of the inner membrane. In this review knowledge gained from the study of changes to the mitochondrial proteome in alcoholic hepatotoxicity will be described and placed into a mechanistic framework to increase understanding of the role of mitochondrial dysfunction in liver disease.

Role of lipid rafts in liver health and disease

Liver diseases are an increasingly common cause of morbidity and mortality; new approaches for investigation of mechanisms of liver diseases and identification of therapeutic targets are emergent. Lipid rafts (LRs) are specialized domains of cellular membranes that are enriched in saturated lipids; they are small, mobile, and are key components of cellular architecture, protein partition to cellular membranes, and signaling events. LRs have been identified in the membranes of all liver cells, parenchymal and non-parenchymal; more importantly, LRs are active participants in multiple physiological and pathological conditions in individual types of liver cells. This article aims to review experimental-based evidence with regard to LRs in the liver, from the perspective of the liver as a whole organ composed of a multitude of cell types. We have gathered up-to-date information related to the role of LRs in individual types of liver cells, in liver health and diseases, and identified the possibilities of LR-dependent therapeutic targets in liver diseases.

Interleukin-10 and chronic liver disease

Interleukin （IL）-10 is an important immunoregulatory cytokine produced by many cell populations. Numerous investigations suggest that IL-10 plays a major role in chronic liver diseases. IL-10 gene polymorphisms are possibly assodated with liver disease susceptibility or se-verity. Recombinant human IL-10 has been produced and is currently tested in clinical trials. These trials may give new insights into the immunobiology of IL-10 and suggest that the IL-10/IL-10 receptor system may become a new therapeutic target.

Measurement of hepatic functional mass by means of ^(13)C-methacetin and ^(13)C-phenylalanine breath tests in chronic liver disease: Comparison with Child-Pugh score and serum bile acid levels

AIM: To evaluate and compare the clinical usefulness of 13C-phenylalanine and 13C-methacetin breath tests in quantitating functional hepatic mass in patients with chronic liver disease and to further compare these results with those of conventional tests, Child-Pugh score and serum bile acid levels.METHODS: One hundred and forty patients (50 HCV-related chronic hepatitis, 90 liver cirrhosis patients) and 40 matched healthy controls were studied. Both breath test and routine liver test, serum levels of cholic and chenodeoxycholic acid conjugates were evaluated.RESULTS: Methacetin breath test, expressed as 60 min cumulative percent of oxidation, discriminated the hepatic functional capacity not only between controls and liver disease patients, but also between different categories of chronic liver disease patients. Methacetin breath test was correlated with liver function tests and serum bile acids.Furthermore, methacetin breath test, as well as serum bile acids, were highly predictive of Child-Pugh scores. The diagnostic power of phenylalanine breath test was always less than that of methacetin breath test.CONCLUSION: Methacetin breath test represents a safe and accurate diagnostic tool in the evaluation of hepatic functional mass in chronic liver disease patients.

Relationship between serum cytokine levels and histopathological changes of liver in patients with hepatitis B

AIM: To investigate whether there was a relationship between the liver functions and fibrosis scores of hepatitis B patients and their TNF-α, IFN-γ,IL-4, and TGF-β1 serum levels based on the studies of liver biopsies. METHODS: Thirty patients with chronic hepatitis B (CHB) receiving no treatment and 30 healthy individuals with negative hepatitis serology and normal values of liver biochemistry were studied. After serum samples of the patients were collected, liver needle biopsy was performed on each patient. Cytokine levels were studied by ELISA. The biopsy materials were scored based on Knodell's histological activity index. RESULTS: In comparison of cytokine levels between CHB patients and control group, TNF-α,IL-4, and TGPβ1 levels of the patients were higher in CHB patients than in the controls, while IFN-γ level was lower in the patients than in the controls. There were significant differences between the groups in TNF-α, IL-4, TGF-β1, and IFN-γ(P<0.005, 0.03, 0.002, 0.0001,respectively).There was a negative correlation between TGF-β1 and IL-4 and IFN-γ(P<0.05), TNF-α and the other cytokines and IFN-γ and IL-4 were not correlated (P>0.05). TGF-β1 was correlated with fibrosis (P<0.05).Liver necroinflammatory activity and fibrosis and TNF-α, IL-4, and IFN-γ were not correlated (P>0.05). CONCLUSION: In the course of HBV infection and its chronic progress, cytokines play an important role. IL-4 and IFN-γ are effective in the chronic progression, while TGF-β1 is effective in the development of fibrosis. Serum cytokine levels may be effective tools in the estimation of chronic progression and fibrosis development.