Significance of serum tissue inhibitor of metalloproteinases-1 in various liver diseases

Serum liver fibrosis markers predict hepatic decompensation in compensated cirrhosis

BACKGROUND AND AIM

The literature is sparse on the association between serum liver fibrosis markers and the development of hepatic decompensation in patients with compensated cirrhosis. We aimed to assessed whether the serum liver fibrosis markers are predictive of the occurrence of hepatic decompensation.

METHODS

We ascertained 688 cirrhotic patients with varying etiologies, between December 2015 to December 2019. Serum hyaluronic acid (HA), laminin (LN), collagen IV (CIV), and N-terminal propeptide of type III collagen (PIIINP) levels were measured at enrollment. All subjects were followed for at least 6 months for occurrence of hepatic decompensation. Cox proportional hazard regression models were used to estimate the hazard ratios (HRs) of hepatic decompensation during follow-up.

RESULTS

During a median follow-up of 22.0 (13.0-32.0) months, decompensation occurred in 69 (10.0%) patients. Multivariate analysis indicated that higher LN (HR: 1.008, 95% confidence interval [CI]: 1.002-1.014, P = 0.011) and CIV (HR: 1.004, 95% CI: 1.001-1.007, P = 0.003) levels were independently associated with hepatic decompensation. Furthermore, patients in the tertile 2 and tertile 3 groups for CIV levels had HRs of 4.787 (1.419, 16.152) (P = 0.012) and 5.153 (1.508, 17.604) (P = 0.009), respectively, for occurrence of decompensation event compared with those in the tertile 1 group.

CONCLUSION

Serum liver fibrosis markers, particularly in CIV, appeared to be reliable biomarkers of disease progression and liver decompensation in patients with compensated cirrhosis with varying etiologies.

A3907, a systemic ASBT inhibitor, improves cholestasis in mice by multiorgan activity and shows translational relevance to humans

BACKGROUND AND AIMS

Cholestasis is characterized by intrahepatic accumulation of bile constituents, including bile acids (BAs), which promote liver damage. The apical sodium-dependent BA transporter (ASBT) plays an important role in BA reabsorption and signaling in ileum, bile ducts, and kidneys. Our aim was to investigate the pharmacokinetics and pharmacological activity of A3907, an oral and systemically available ASBT inhibitor in experimental mouse models of cholestasis. In addition, the tolerability, pharmacokinetics, and pharmacodynamics of A3907 were examined in healthy humans.

APPROACH AND RESULTS

A3907 was a potent and selective ASBT inhibitor in vitro. In rodents, orally administered A3907 distributed to the ASBT-expressing organs, that is, ileum, liver, and kidneys, and dose dependently increased fecal BA excretion. A3907 improved biochemical, histological, and molecular markers of liver and bile duct injury in Mdr2-/- mice and also had direct protective effects on rat cholangiocytes exposed to cytotoxic BA concentrations in vitro . In bile duct ligated mice, A3907 increased urinary BA elimination, reduced serum BA levels, and prevented body weight loss, while improving markers of liver injury. A3907 was well tolerated and demonstrated target engagement in healthy volunteers. Plasma exposure of A3907 in humans was within the range of systemic concentrations that achieved therapeutic efficacy in mouse.

CONCLUSIONS

The systemic ASBT inhibitor A3907 improved experimental cholestatic disease by targeting ASBT function at the intestinal, liver, and kidney levels, resulting in marked clearance of circulating BAs and liver protection. A3907 is well tolerated in humans, supporting further clinical development for the treatment of cholestatic liver diseases.

A Novel Non-invasive Model Based on GPR for the Prediction of Liver Fibrosis in Patients With Chronic Hepatitis B

Background: Some controversy remains regarding conventional serum indices for the evaluation of liver fibrosis. Therefore, we aimed to combine the existing index with other serum parameters to discriminate liver fibrosis stages in patients with chronic hepatitis B (CHB). Methods: A total of 1,622 treatment-naïve CHB patients were divided into training (n = 1,211) and validation (n = 451) cohorts. Liver histology was assessed according to the Scheuer scoring scheme. All common demographic and clinical parameters were analyzed. Results: By utilizing the results of the logistic regression analysis, we developed a novel index, the product of GPR, international normalized ratio (INR), and type IV collagen (GIVPR), to discriminate liver fibrosis. In the training group, the areas under the ROCs (AUROCs) of GIVPR, APRI, FIB-4, and GPR for significant fibrosis were 0.81, 0.75, 0.72, and 0.77, respectively; the AUROCs of GIVPR, APRI, FIB-4, and GPR for advanced fibrosis were 0.82, 0.74, 0.74, and 0.78, respectively; and the AUROCs of GIVPR, APRI, FIB-4, and GPR for cirrhosis were 0.87, 0.78, 0.78, and 0.83, respectively. Similar results were also obtained in the validation group. Furthermore, the decision curve analysis suggested that GIVPR represented superior clinical benefits in both independent cohorts. Conclusion: The GIVPR constructed on GPR represents a superior predictive model for discriminating liver fibrosis in CHB patients.

Serum liver fibrosis markers discriminate significant liver inflammation in chronic hepatitis B patients with normal or near-normal alanine aminotransferase

Chronic liver inflammation caused by chronic hepatitis B virus (CHB) infection leads to liver cirrhosis and hepatocellular carcinoma. Recently, the role of alanine aminotransferase (ALT) as a predictor of liver inflammation has been questioned. The aim of this study was to investigate the utility of noninvasive fibrosis markers including hyaluronic acid (HA), collagen type IV (CIV), N-terminal propeptide of type III procollagen (PIIINP), and laminin (LN) in identifying significant liver inflammation in patients with CHB, especially in patients with normal or near-normal ALT. A total of 242 CHB patients who underwent liver biopsy were enrolled. The serum levels of ALT, aspartate aminotransferase, HA, CIV, PIIINP, and LN were quantified and the relationship between histological staging and serum markers was systematically analyzed. Serum CIV, PIIINP, HA, and LN levels increased significantly along with the increasing severity of liver inflammation. Multivariate analysis showed that CIV and LN were independently associated with significant inflammation. CIV, PIIINP, HA, and LN levels were found to have high diagnostic values for predicting significant inflammation in patients with CHB (area under the curve, AUC = 0.807, 0.795, 0.767, and 0.703, respectively). The combined index for the identification of significant inflammation, including CIV, PIIINP, HA, and LN levels, significantly improved diagnostic performance (AUC = 0.851). Moreover, the combined index also achieved excellent diagnostic accuracy (AUC = 0.861) in patients with CHB with normal or near-normal ALT. In conclusion, the combined index may be a strong indicator for discriminating significant liver inflammation, especially in patients with CHB with normal or near-normal ALT.

Diagnostic performance of collagen IV and laminin for the prediction of fibrosis and cirrhosis in chronic hepatitis C patients: a multicenter study

BACKGROUND/AIM

To date, liver biopsy has been the gold standard used for the assessment of liver fibrosis in patients with chronic hepatitis C. Our aim was to evaluate the diagnostic performance of a panel of simple blood markers of liver fibrosis and the development a novel score to replace liver biopsy.

PATIENTS AND METHODS

Liver biochemical profile including transaminases, bilirubin, alkaline phosphatase, and albumin, in addition to platelet count, was evaluated using standard methods in 305 chronic hepatitis C patients. Serum type IV collagen and laminin were assayed using the ELISA technique. Liver biopsies were performed. Statistical analyses were carried out by logistic regression and receiver operating characteristic curves to assess and compare the diagnostic accuracy of blood markers. A stepwise combination algorithm was developed and validated in 317 additional patients.

RESULTS

The Fibrosis Discriminant Score (FDS) was developed combining collagen, laminin, aspartate aminotransferase/platelet ratio index, and albumin. FDS produced an area under receiver operating characteristic curve of 0.831 for significant fibrosis, 0.791 for advanced fibrosis, and 0.881 for cirrhosis. The FDS was correctly classified in 82% of patients with significant fibrosis with 79% sensitivity and 88% specificity at cut-off 0.66 or more. Similar results were obtained in a validation study in which, of 317 patients, liver biopsy could have been avoided in 81%.

CONCLUSION

A simple fibrosis index can be useful to select hepatitis C virus-infected patients with a very low risk of significant fibrosis in whom the protocol of liver biopsies may be avoided.

Performance of diagnostic biomarkers in predicting liver fibrosis among hepatitis C virus-infected Egyptian children

The aim of the present study was to identify specific markers that mirror liver fibrosis progression as an alternative to biopsy when biopsy is contraindicated, especially in children. After liver biopsies were performed, serum samples from 30 hepatitis C virus (HCV) paediatric patients (8-14 years) were analysed and compared with samples from 30 healthy subjects. All subjects were tested for the presence of serum anti-HCV antibodies. Direct biomarkers for liver fibrosis, including transforming growth factor-β1, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), hyaluronic acid (HA), procollagen type III amino-terminal peptide (PIIINP) and osteopontin (OPN), were measured. The indirect biomarkers aspartate and alanine aminotransferases, albumin and bilirubin were also tested. The results revealed a significant increase in the serum marker levels in HCV-infected children compared with the healthy group, whereas albumin levels exhibited a significant decrease. Significantly higher levels of PIIINP, TIMP-1, OPN and HA were detected in HCV-infected children with moderate to severe fibrosis compared with children with mild fibrosis (p < 0.05). The diagnostic accuracy of these direct biomarkers, represented by sensitivity, specificity and positive predictive value, emphasises the utility of PIIINP, TIMP-1, OPN and HA as indicators of liver fibrosis among HCV-infected children.

Clinical utility of serum matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-2 concentrations in the assessment of liver fibrosis due to chronic hepatitis B

OBJECTIVE

To explore the relationships between serum concentrations of tissue inhibitor of metalloproteinase-2 (TIMP-2) and matrix metalloproteinase-2 (MMP-2), and severity of liver fibrosis in chronic hepatitis B.

METHODS

A total of 101 patients with hepatitis B and 54 healthy control subjects were consecutively enrolled. Serum MMP-2 and TIMP-2 were quantified by enzyme-linked immunosorbent assay.

RESULTS

Serum MMP-2 concentrations in patients with stage F2 - F4 fibrosis were significantly higher than in patients with stage F0 - F1 fibrosis and control subjects, but no significant difference was found between patients with stage F0 - F1 fibrosis and control subjects. Significant differences in serum TIMP-2 concentrations were found between patients with stages F2 - F4 and F0 - F1 fibrosis, and between stages F0 - F1 fibrosis and healthy control subjects. Areas under the receiver operating characteristic curves of serum TIMP-2 and MMP-2 for predicting clinically significant fibrosis (stage F2 - F4) were 0.899 and 0.770, respectively.

CONCLUSION

Serum TIMP-2 and MMP-2 assessment may represent a valuable noninvasive diagnostic test for liver fibrosis in hepatitis B.

Paediatric cholestatic liver disease: Diagnosis, assessment of disease progression and mechanisms of fibrogenesis

Cholestatic liver disease causes significant morbidity and mortality in children. The diagnosis and management of these diseases can be complicated by an inability to detect early stages of fibrosis and a lack of adequate interventional therapy. There is no single gold standard test that accurately reflects the presence of liver disease, or that can be used to monitor fibrosis progression, particularly in conditions such as cystic fibrosis. This has lead to controversy over how suspected liver disease in children is detected and diagnosed. This review discusses the challenges in using commonly available methods to diagnose hepatic fibrosis and monitor disease progression in children with cholestatic liver disease. In addition, the review examines the mechanisms hypothesised to be involved in the development of hepatic fibrogenesis in paediatric cholestatic liver injury which may ultimately aid in identifying new modalities to assist in both disease detection and therapeutic intervention.

Circulating markers of liver fibrosis progression

INTRODUCTION

Fibrogenesis is a typical reaction of the liver to injury. In the case of overstimulation of fibrogenesis clinically significant fibrosis and, eventually, cirrhosis occur. Treatment of liver cirrhosis is limited, therefore it is important to screen and monitor patients at risk of cirrhosis. Noninvasive parameters are ideal for this purpose due to their risk profile and repeatability.

METHODS

Systematic review of literature.

RESULTS

Among large number of proposed biomarkers, there is a distinct difference between two groups or classes. Class I biomarkers are associated with the process of fibrogenesis, their presence in the serum is the result of the increased turnover of extracellular matrix. Class II biomarkers and their combinations are mostly markers of liver function or structural damage. We have identified 27 Class I and 13 Class II biomarkers that have been proposed in the literature. We have evaluated in detail those which reached limited clinical application.

CONCLUSION

General clinical acceptance of these biomarkers is low because of various drawbacks. Simple and readily available biomarkers have low accuracy in predicting liver fibrosis and more advanced markers have low cost-benefit ratio. Therefore liver biopsy remains the "gold standard" for diagnosis of fibrosis. However potential noninvasive alternatives exist and their implementation could be valuable.

Serum levels of hyaluronic acid and tissue metalloproteinase inhibitor-1 combined with age predict the presence of nonalcoholic steatohepatitis in a pilot cohort of subjects with nonalcoholic fatty liver disease

Hyaluronic acid (HA) and tissue inhibitor of metalloproteinase 1 (TIMP-1) are reliable markers of liver fibrosis and are closely linked to the proinflammatory status. In this pilot cohort study, we attempted to identify a clinical score that would predict the severity of nonalcoholic fatty liver disease (NAFLD) based on clinical variables and serum markers of fibrosis and inflammation. The cohort included 46 patients with histologically confirmed NAFLD (76.1% male; mean age, 43+/-13 years; mean body mass index [BMI], 27.8+/-3.5). Serum transforming growth factor beta (TGF-beta), HA, TIMP, and matrix metalloproteinase (MMP) levels were measured with commercial enzyme-linked immunoassay (ELISA) kits. Demographic features and clinical and laboratory findings were subjected to univariate and multivariate binary logistic regression analysis to construct the mathematical model. Receiver operating characteristic curve (ROC) analysis was used to identify a threshold value for diagnosis of NASH and to assess its sensitivity and specificity. Serum levels of HA and TIMP-1 were statistically different in patients with nonalcoholic steatohepatitis (NASH) (P<0.05). Logistic regression analysis of several clinical variables indicated patient age as the only independent predictor of NASH (odds ratio [OR], 1.129, 95% confidence interval [CI], 1.019-1.251, P=0.020). The mathematical model constructed on the basis of these results included age, TIMP-1, and HA levels. A value of 148.27 or more identified patients with NASH with 85.7% sensitivity, 87.1% specificity, and negative and positive predictive values of 96.4% and 60%, respectively. This model seems to represent a reliable noninvasive tool for excluding the presence of NASH. If validated in larger prospective cohort studies, it might be useful for determining when a liver biopsy is actually warranted in patients with NAFLD.

Inhibitory effect of Hemidesmus indicus and its active principle 2-hydroxy 4-methoxy benzoic acid on ethanol-induced liver injury

The study evaluates the inhibitory activity of ethanolic root extract of Hemidesmus indicus (H. indicus) and its active principle 2-hydroxy 4-methoxy benzoic acid (HMBA) on liver fibrotic markers and characteristics such as collagen content, matrix metalloproteinases (MMPs) 2 and 9 in ethanol-fed rats. Experimental groups were control, H. indicus (500 mg/kg body weight every day during the last 30 days), HMBA (200 microg/kg body weight every day during the last 30 days), alcohol (5 g/kg body weight by intragastric intubation everyday, i.e. throughout the experimental period of 60 days), alcohol plus H. indicus and alcohol plus HMBA. Ethanol administration significantly increased the levels of liver collagen and hydroxy proline content, cross-linked fluorescence, shrinkage temperature and lipid peroxidation and significantly decreased the solubility of liver collagen and the ascorbic acid content when compared with control rats. On treatment with H. indicus and HMBA the ethanol-fed rats showed significantly reduced levels of liver collagen and hydroxyproline content, cross-linked fluorescence, shrinkage temperature and lipid peroxidation and enhanced solubility of liver collagen and ascorbic acid levels when compared with untreated ethanol-fed rats. MMPs were extracted from the liver of control, H. indicus-treated, HMBA-treated, ethanol-administered, ethanol with H. indicus-coadministered and ethanol with HMBA-coadministered rats. The inhibition was analyzed by gelatin zymography and the percentage of expression was determined by a gel documentation system. The activities of MMPs 2 and 9 were significantly increased in ethanol-supplemented rats. Cotreatment of H. indicus/HMBA with ethanol showed significantly decreased activities of these enzymes when compared with those of the untreated rats. H. indicus/HMBA alone treatment showed no such significant alterations. Thus, our present study reveals the strong inhibitory activity of H. indicus and HMBA on the quantitative and qualitative properties of hepatic collagen and also MMPs involved in the extracellular matrix degradation during ethanol intoxication.

Serum markers of hepatic fibrogenesis in cystic fibrosis liver disease

BACKGROUND/AIMS

Hepatic fibrosis contributes to adverse outcome in cystic fibrosis (CF). Early detection of CF liver disease (CFLD) may identify patients at risk of significant complications. To evaluate the utility of serum markers to detect hepatic fibrosis in children with CFLD vs. CF patients without liver disease (CFnoLD) and controls.

METHODS

Sera from 36 CFLD, 30 CFnoLD and 39 controls were assessed for tissue inhibitor of matrix metalloproteinase (MMP) (TIMP)-1, collagen (CL)-IV, MMP-2, hyaluronic acid (HA) and prolyl hydroxylase (PH) by enzyme immunoassay and were correlated with hepatic fibrosis score in CFLD.

RESULTS

TIMP-1, PH and CL-IV were increased in CFLD vs. CFnoLD and controls. Fibrosis score was negatively correlated with TIMP-1 (r=-0.34, P=0.06) and PH (r=-0.48, P=0.008). Receiver-operating characteristics analysis showed CL-IV (AUC 0.785, P<0.0001) and TIMP-1 (AUC 0.765, P<0.0001) differentiated CFLD from CFnoLD and controls, while PH (AUC 0.814, P<0.0001) predicted early fibrogenesis. Diagnostic accuracy improved using logistic regression combining (i) CL-IV, TIMP-1, PH to identify CFLD (AUC 0.831, P<0.0001) and (ii) TIMP-1, PH to identify CFLD patients with no fibrosis (AUC 0.852, P<0.02).

CONCLUSIONS

Elevated TIMP-1, CL-IV, PH may be indicators of hepatic fibrogenesis in CF. Increased TIMP-1, PH may be early markers of CFLD.

Developing strategies for liver fibrosis treatment

Liver fibrosis represents a major worldwide healthcare burden. Current therapy is limited to removing the causal agent. This approach is successful in some diseases; particularly haemochromatosis and chronic viral hepatitis. However, for many patients treatment is not possible, while other patients present to medical attention at an advanced stage of fibrosis. There is therefore a great need for novel therapies for liver fibrosis. The hepatic stellate cell has been recognised to be responsible for most of the excess extracellular matrix observed in chronic liver fibrosis. The detailed understanding of hepatic stellate cell biology has allowed the rational design of novel antifibrotic therapies. This review describes for the general reader the novel emerging therapies for liver fibrosis.

Matrix metalloproteinases and their inhibitors in acute viral hepatitis

Matrix metalloproteases (MMPs) and their inhibitors are effector molecules involved in extracellular matrix remodelling. The serum profile for these proteolytic enzymes and their inhibitors during acute self-limiting viral hepatitis has not been studied. We therefore determined serum concentrations of MMP-1, MMP-3, MMP-2, MMP-9 and their inhibitors (tissue inhibitors of metalloproteinase) TIMP-1, TIMP-2 and alpha2 macroglobulin (AMG) in the serum of patients during the icteric stage of self-limiting acute viral hepatitis. Transforming growth factor-beta (TGF-beta) and interleukin (IL)-10, two cytokines involved in the regulation of MMPs and TIMPs were also assessed. Nineteen patients (12 men, seven women) with a mean age of 29.9 years (range 16-65 years) participated in the study. Fifteen had hepatitis B virus (HBV, two HCV and two HAV infection. The values of patients were compared with those obtained from 15 blood donor controls (eight men, seven women), mean age 36.2 years (range 18-55 years). Serum levels of TGF-beta, IL-10, MMP-1, MMP-3, MMP-2, MMP-9, TIMP-1 and TIMP-2 were assessed by ELISA. MMP-2 and MMP-9 were also measured by a zymogram protease assay. alpha2 macroglobulin (AMG) was measured by nephelometry. Compared with the healthy controls the mean serum concentrations of all MMPs were significantly decreased in the acute hepatitis patients. There was no difference in the serum concentration of TIMP-1 between patients and the controls. Serum levels of TIMP-2 (P < 0001), TGF-beta (P < 0.05), IL-10 (P < 0.001) and AMG (P < 0001) were increased in patients compared to healthy controls. A statistically significant negative correlation by linear regression analysis was found between AMG and MMP-1 (P=0003). The decreased levels of MMPs observed, together with normal and increased levels of TIMP-1 and TIMP-2, may indicate an attempt to limit matrix degradation at this stage of disease resolution. The increased levels of the anti-inflammatory cytokines IL-10 and TGF-beta might be the underlying mechanism responsible for the above effect. AMG inhibition especially for MMP-1 may play an additional important role.

Diagnostic potential of circulating TIMP-1 and MMP-2 as markers of liver fibrosis in patients with chronic hepatitis C

BACKGROUND

Circulating levels of tissue inhibitor of metalloproteinase (TIMP)-1 and matrix metalloproteinase (MMP)-2 are investigated as parameters for the diagnosis of fibrosis in chronic liver disease. We evaluated their diagnostic potential in comparison to hepatic histology, serum hyaluronate and standard liver function tests.

METHODS

Commercially available ELISA assays were used to study circulating values of TIMP-1 and MMP-2 (Bindazyme, Biotrak, Quantikine) in patients with chronic hepatitis C (CAH; n=59), hepatitis C virus-induced cirrhosis (n=19) and 30 healthy controls. Hepatic histology was evaluated using the Hepatitis-Activity-Index according to Ishak et al. [J. Hepatol., 22 (1995) 696-699], quantifying separately inflammatory activity and fibrosis.

RESULTS

Normal ranges for TIMP-1 and MMP-2 values differed for the different assays. Nevertheless, the various assays showed similar diagnostic ability and linear correlation. MMP-2 values were similar in controls and in CAH patients with and without fibrosis, but increased significantly in cirrhosis. TIMP-1 values showed a steady increase from normal to CAH without fibrosis, hepatitis with fibrosis, and cirrhosis. The diagnostic potential of serum MMP-2 to detect fibrosis was low with a sensitivity of 7% in the two assays used and an overall diagnostic efficiency of 56% and 58%. The potential of circulating MMP-2 to detect cirrhosis was higher with sensitivities of 74% and 83% and specificities of 96% and 100%, resulting in a diagnostic efficiency of 92% in the different assays. Plasma TIMP-1 values detect fibrosis with a sensitivity of 52% and 67% and a specificity of 68% and 88% resulting in overall efficiency rates of 68% and 71%, respectively. TIMP-1 values detect cirrhosis with 100% sensitivity but only 56% and 75% specificity. The diagnostic potential of circulating TIMP-1 was similar to that of hyaluronate and better than that of enzymes or albumin values.

CONCLUSION

Plasma values of TIMP-1 and MMP-2 are able to detect cirrhosis with high sensitivity. TIMP-1 values also detect fibrosis with comparable efficiency. Regular determinations of both TIMP-1 and MMP-2 in CAH patients may be used as indicators of increasing fibrosis and the development of cirrhosis.

Matrix metalloproteinase (MMP)-2, MMP-7, and tissue inhibitor of metalloproteinase-1 are closely related to the fibroproliferative process in the liver during chronic hepatitis C

BACKGROUND/AIMS

To study whether expression of matrix metalloproteinases and their inhibitors correlate with ongoing fibrogenesis, we measured hepatic mRNA levels of matrix metalloproteinase (MMP) -2, MMP-7, and MMP-9 as well as tissue inhibitor of metalloproteinase (TIMP) -1, TIMP-2, and TIMP-3 and compared it to histology, procollagen IV alpha-1 chain mRNA levels, and biochemical parameters in patients with chronic active hepatitis C (CAH).

METHODS

Quantitative reverse transcription-polymerase chain reaction/enzyme-linked immunossorbent assay using in vitro transcribed competitor and standard RNA were performed from ten normal livers (N), 29 CAH liver biopsies and seven samples with hepatitis C virus (HCV)-induced end-stage cirrhosis (Ci).

RESULTS

From N to Ci both TIMP and MMP RNA expression increased. However, none of the RNA levels differed significantly between CAH patients with and without fibrosis. Non-parametric correlation analysis and receiver operating characteristics curves show that MMP-2, MMP-7, and TIMP-1 provide the best discrimination between cirrhosis and pre-cirrhotic stages. They also correlate with histologic and biochemical inflammatory activity and with procollagen IV mRNA.

CONCLUSION

Hepatic fibroproliferation is associated with alterations of hepatic TIMP and MMP expression. The relation of hepatic TIMP and MMP mRNA levels to disease stage and inflammatory activity underlines their potential as diagnostic markers in chronic liver disease.

Expression of Matrix Metalloproteinase-2 and -9 and Their Inhibitors in Peripheral Blood Cells of Patients with Chronic Hepatitis C

Background: To clarify whether circulating matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) can be used as serum markers of fibroproliferation in chronic liver diseases, we studied the expression of MMP-2 and MMP-9 in relation to TIMP-1 and TIMP-2 in peripheral blood mononuclear leukocytes (MNLs) and polymorphonuclear leukocytes (PMLs), and compared this expression to circulating concentrations and hepatic histology in patients with chronic active hepatitis C (CAH).

Methods: Quantitative reverse transcription-PCR/ELISA assays were performed for MMP and TIMP RNA, and corresponding circulating protein concentrations were studied by ELISA in 20 healthy controls, 40 patients with CAH, and 20 patients with hepatitis C-induced cirrhosis (Ci).

Results: MMP-2 mRNA was found almost exclusively in the liver, MMP-9 mRNA in leukocytes. TIMP RNA-equivalents were decreased in MNLs of CAH patients, but neither MMP-9 nor TIMP RNA expression showed any correlation to the extent of inflammation and fibrosis. MMP-2 and TIMP-1 protein concentrations were increased in Ci patients and showed a wide overlap in CAH patients and healthy controls. MMP-9 values were lower in CAH and Ci patients than in healthy controls. TIMP-2 values showed a wide overlap in all three groups. The MMP-2/TIMP-1 and MMP-9/TIMP-1 ratios were lower in Ci patients than in healthy controls; the MMP-2/TIMP-2 and MMP-9/TIMP-2 ratios were not different. Circulating TIMP-1 and the MMP-2/TIMP-1 ratio correlated to the inflammatory activity in liver biopsies, but only the circulating MMP-2/TIMP-1 ratio also correlated with the degree of fibrosis.

Conclusions: Peripheral blood cell expression of MMP-2, MMP-9, and TIMP revealed no correlation with the circulating concentrations of these proteins. Only the circulating MMP-2/TIMP-1 ratio correlated to the histological degree of fibrosis in hepatitis C and should be further evaluated as a progression marker in patients with chronic liver disease.

Elevated serum type IV collagen: a sensitive indicator of the presence of cirrhosis in haemochromatosis

BACKGROUND/AIM

Hereditary haemochromatosis can now be diagnosed by genetic testing, although determining the presence or absence of cirrhosis remains crucial to patient management. While many studies have investigated the utility of various serum markers of cirrhosis in chronic liver diseases, few have examined specifically patients with hereditary haemochromatosis. The aim of this study was to assess the utility of serum type IV collagen and serum laminin in diagnosing hepatic fibrosis and cirrhosis in patients with hereditary haemochromatosis.

METHODS

The study group consisted of 42 patients with hereditary haemochromatosis and 19 Caucasian controls. Serum type IV collagen, laminin, matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase (TIMP-1) concentrations were measured by enzyme-linked immunosorbant assay in serum from patients with haemochromatosis and control subjects. Liver biopsies from patients with haemochromatosis were graded for fibrosis and correlated with serum markers of hepatic fibrosis.

RESULTS

Serum type IV collagen concentration was significantly increased in haemochromatosis patients compared to controls (130+/-79 ng/ml vs 81 +/- 17 ng/ml, p<0.05) and was significantly correlated with both the grade of histological fibrosis (r=0.67, p<0.0001) and serum MMP-2 levels (r=0.42, p<0.05). A serum type IV collagen concentration > 115 ng/ml (mean+2 SD of controls) was 100% sensitive and 69% specific in detecting severe (grade 3) fibrosis and cirrhosis. The sensitivity results of serum laminin and TIMP-1 were 11% and 56% respectively.

CONCLUSIONS

Elevated serum type IV collagen is a sensitive indicator of the presence of severe fibrosis and cirrhosis in patients with haemochromatosis. Useful markers of hepatic fibrosis in other chronic liver diseases may not be applicable to haemochromatosis.

Spatial distribution of tissue inhibitor of metalloproteinase-1 mRNA in chronic liver disease

BACKGROUND/AIMS

Tissue inhibitor of metalloproteinase-1, a specific inhibitor of matrix metalloproteinases, plays an important role in the pathogenesis of fibrosis and tumor progression. However, the precise expression of tissue inhibitor of metalloproteinase-1 messenger RNA in human hepatic fibrosis has not yet been defined. We investigated the spatial distribution of tissue inhibitor of metalloproteinase-1 messenger RNA in chronic human liver disease.

METHODS

Northern and in situ hybridization of probes to tissue inhibitor of metalloproteinase-1 messenger RNA were performed in specimens from 16 surgically resected human livers. Immunohistochemical staining of sections for tissue inhibitor of metalloproteinase-1 and immunoelectron microscopy were also performed.

RESULTS

Northern hybridization demonstrated that expression of tissue inhibitor of metalloproteinase-1 messenger RNA was increased 3.9-fold in mild chronic hepatitis, 6.8-fold in moderate chronic hepatitis, and 6.4-fold in cirrhosis, compared with control liver. In situ hybridization showed the expression of tissue inhibitor of metalloproteinase-1 messenger RNA in spindle-shaped cells in the fibrous septa and lobules in chronic hepatitis and cirrhosis; these cells were immunohistochemically positive for a-smooth muscle actin. Immunoelectron microscopy revealed localization of tissue inhibitor of metalloproteinase-1 in between fibers, to the rough endoplasmic reticula of stellate cells located in the lobules and periportal areas, and to fibroblasts in the fibrous septa. These results indicate that tissue inhibitor of metalloproteinase-1 was produced mainly by stellate cells in the specimens of chronic liver diseases.

CONCLUSIONS

Expression of tissue inhibitor of metalloproteinase-1 messenger RNA is increased in hepatic fibrosis and stellate cells are involved primarily in its expression.

Clinical usefulness of serum tissue inhibitor of metalloproteinases (TIMP)-2 assay in patients with chronic liver disease in comparison with serum TIMP-1

Tissue inhibitors of metalloproteinases (TIMPs) are involved in liver fibrosis through impaired matrix degradation. Previous studies showed that the serum level of TIMP-1 was increased in patients with chronic liver disease, reflecting the liver TIMP-1 level, and that it is useful for assessing liver fibrosis. An enzyme immunoassay for TIMP-2 is now available. In this study, we examined the clinical usefulness of this serum TIMP-2 test for liver fibrosis in patients with chronic liver disease, in comparison with the serum TIMP-1 test. The serum TIMP-2 concentration was 61 +/- 13 ng/ml in healthy controls (n = 32), and 18% higher in the group of chronic active hepatitis (CAH) patients (n = 34), 64% higher in the liver cirrhosis (LC) group (n = 33) and 44% higher in the hepatocellular carcinoma (HCC) group (n = 61), and similar to the control level in the chronic persistent hepatitis (CPH) group (n = 23). In contrast, the serum TIMP-1 concentration was 155 +/- 17 ng/ml in the healthy controls, 18% higher in CPH, 35% in CAH, 63% higher in LC and 92% higher in HCC. The serum TIMP-2 level was related to the histological degrees of both periportal necrosis and liver fibrosis, as well as to the serum TIMP-1 level. However, the relationships for TIMP-2 were weaker compared to those of serum TIMP-1. These results suggest that compared to the serum TIMP-1 level, changes in the serum TIMP-2 level in chronic liver disease are less liver-specific, and the serum TIMP-2 level is less useful in the assessment of liver fibrosis in chronic liver disease.