Clinical manifestations of liver inflammation in alcohol-associated liver disease (ALD) can range from asymptomatic to severe alcoholic hepatitis. While biopsy is the gold standard for identifying liver inflammation, it is an invasive procedure with risks of bleeding, visceral damage, and infection. We aim to establish the state of the current literature on non-invasive markers of inflammation in ALD. We searched Ovid MEDLINE, Embase, and the Cochrane Library for original studies on the association between one or more non-invasive biomarker(s) and histological inflammation or hepatitis in ALD patients. Exclusion criteria were lack of histological data, abstract only, non-English-language articles, and animal studies. Two independent reviewers screened abstracts, reviewed full texts, and extracted data from included papers. Our search identified 8051 unique studies. Title and abstract screening resulted in 563 studies, and full-text screening resulted in 31 studies for final inclusion. The majority were single-center observational cohorts with an average sample size of 124. Review of these studies identified 44 unique biomarkers and 8 calculated scores associated with histological inflammation and/or hepatitis, in addition to a metabolomic panel of 468 metabolites. Six studies examined diagnostic accuracy for histological inflammation and/or hepatitis. The highest area under the receiver operating characteristic curve was 0.932 using a model based on four metabolites. This review highlights the available literature on non-invasive markers of inflammation in ALD. There is a dearth of studies that evaluate the diagnostic accuracy of these biomarkers, and larger studies are needed to confirm findings identified in small cohorts.

Recent data have emphasized the role of inflammation and intestinal immunoglobulin A (IgA) responses in the pathogenesis of alcoholic liver disease (ALD). In order to further explore such associations, we compared IgA titers against antigens targeted to ethanol metabolites and tissue transglutaminase with pro- and anti-inflammatory mediators of inflammation, markers of liver status, transferrin protein desialylation and extracellular matrix metabolism in alcohol-dependent patients with or without liver disease and in healthy controls. Serum IgAs against protein adducts with acetaldehyde (HbAch-IgA), the first metabolite of ethanol, and tissue transglutaminase (tTG-IgA), desialylated transferrin (CDT), pro- and anti-inflammatory cytokines, markers of liver status (GT, ALP) and extracellular matrix metabolism (PIIINP, PINP, hyaluronic acid, ICTP and CTx) were measured in alcohol-dependent patients with (n = 83) or without (n = 105) liver disease and 88 healthy controls representing either moderate drinkers or abstainers. In ALD patients, both tTG-IgA and HbAch-IgA titers were significantly higher than those in the alcoholics without liver disease (p < 0.0005 for tTG-IgA, p = 0.006 for Hb-Ach-IgA) or in healthy controls (p < 0.0005 for both comparisons). The HbAch-IgA levels in the alcoholics without liver disease also exceeded those found in healthy controls (p = 0.0008). In ROC analyses, anti-tTG-antibodies showed an excellent discriminative value in differentiating between ALD patients and healthy controls (AUC = 0.95, p < 0.0005). Significant correlations emerged between tTG-IgAs and HbAch-IgAs (rs = 0.462, p < 0.0005), CDT (rs = 0.413, p < 0.0001), GT (rs = 0.487, p < 0.0001), alkaline phosphatase (rs = 0.466, p < 0.0001), serum markers of fibrogenesis: PIIINP (rs = 0.634, p < 0.0001), hyaluronic acid (rs = 0.575, p < 0.0001), ICTP (rs = 0.482, p < 0.0001), pro-inflammatory cytokines IL-6 (rs = 0.581, p < 0.0001), IL-8 (rs = 0.535, p < 0.0001) and TNF-α (rs = 0.591, p < 0.0001), whereas significant inverse correlations were observed with serum TGF-β (rs = -0.366, p < 0.0001) and CTx, a marker of collagen degradation (rs = -0.495, p < 0.0001). The data indicate that the induction of IgA immune responses toward ethanol metabolites and tissue transglutaminaseis a characteristic feature of patients with AUD and coincides with the activation of inflammation, extracellular matrix remodeling and the generation of aberrantly glycosylated proteins. These processes appear to work in concert in the sequence of events leading from heavy drinking to ALD.

Assessing liver fibrosis in patients after liver transplantation is still largely dependent on liver biopsy. Especially in children, noninvasive methods are of utmost importance. We evaluated tissue inhibitor of metalloproteinase 1 (TIMP1) and AST-to-Platelet Ratio Index (APRI) and their potential as serum biomarkers to predict liver allograft fibrosis (LAF) in a pediatric cohort.

In this retrospective, observational study, we analyzed 91 protocol liver biopsy specimens from 73 children after pediatric liver transplantation (PLT) and compared histological stage of liver fibrosis using LAF Score (LAFSc) and Ishak Score (IshakSc) to TIMP1-serum concentration and APRI using ROC analysis.

In our cohort, TIMP1 and APRI reliably predict LAF. Depending on the histological scoring system, cutoff values for TIMP1 were 328 ng/mL (IshakSc ≥ IV) and 351 ng/mL (LAFSc ≥ 5) with AUC of 0.86 and 0.98. The cutoff for APRI was 0.8 with AUC of 0.87 (IshakSc ≥ IV) and 0.94 (LAFSc ≥ 5). Using LAFSc, TIMP1 and APRI showed excellent diagnostic accuracy to detect severe LAF (LAFSc ≥ 5) with PPV of ≥ 90% and NPV of 100%.

TIMP1 and APRI are accurate biomarkers to predict severe LAF in children. The use of TIMP1 and APRI will not replace but complement liver biopsies after PLT to further improve our understanding of each individual patient.

The diagnostic assessment of liver fibrosis is an important step in the management of patients with chronic liver diseases. Liver biopsy is considered the gold standard to assess necroinflammation and fibrosis. However, recent technical advances have introduced numerous serum biomarkers and imaging tools using elastography as noninvasive alternatives to biopsy. Serum markers can be direct or indirect markers of the fibrosis process. The elastography-based studies include transient elastography, acoustic radiation force imaging, supersonic shear wave imaging and magnetic resonance elastography. As accumulation of clinical data shows that noninvasive tests provide prognostic information of clinical relevance, non-invasive diagnostic tools have been incorporated into clinical guidelines and practice. Here, the authors review noninvasive tests for the diagnosis of liver fibrosis.

Chronic liver disease represents a major public health problem, accounting for significant morbidity and mortality worldwide. Their prognosis and management greatly depends on the amount and progression of liver fibrosis with time and the risk of development of cirrhosis. Historically, liver biopsy was considered to be the gold standard for the detection of fibrosis. Nevertheless, liver biopsy is an invasive procedure that has limitations in terms of patient acceptance, risk-benefit ratio, cost-effectiveness, and its availability in various geographic regions. Moreover, it is a questionable gold standard due to significant sampling error and intraobserver and interobserver variability. These limitations have led to the development of noninvasive techniques for assessing the presence and the degree of liver fibrosis. This review aims to revise the most recent data from the literature about noninvasive methods useful in the evaluation of liver fibrosis.

Alcoholic liver disease (ALD) is a significant cause of death and morbidity. Detection of liver fibrosis at an early stage could provide opportunities for more optimal management. Serum markers of liver fibrosis offer an alternative to biopsy. Evidence of the performance of biomarkers in ALD is needed and a systematic review to evaluate available studies was conducted.

Electronic databases were searched. Studies were included if they evaluated paired samples of biopsy and serum, and presented data as sensitivity, specificity, or ROC curves.

15 studies were included- median participant number = 146 (range 44-1034). Studies differed with respect to patient populations. 6 single markers were evaluated (mostly Hyaluronic Acid), and ten combined panels. Biomarkers could discriminate between people with severe fibrosis/cirrhosis with high diagnostic accuracy- HA (median AUROC 0.79 range 0.69-0.93), panels (median AUROC 0.83 range 0.38-0.95). Significant heterogeneity precluded pooling. Performance was poorer for detecting less severe fibrosis.

There are limited numbers of small studies evaluating the accuracy of biomarkers in identifying fibrosis on biopsy in ALD. Some showed promise (both HA alone and some panels) in the identification of cirrhosis/severe fibrosis and could be used to rule it out in heavy drinkers. Biomarkers less accurate with less severe fibrosis.

It is widely recognized that tissue inhibitors of metalloproteinases (TIMPs), especially TIMP-1 and -2, play a key role in the progression of hepatic fibrosis. In the present study, we examined the changes in TIMP-1 and -2 expressions in the early stage of porcine serum (PS)-induced liver fibrosis in Brown Norway (BN) and Wistar rats. The rats were injected intraperitoneally with 0.5 ml/head of PS twice a week for up to 8 weeks and examined at 2, 4 and 8 weeks. Hepatic fibrosis and inflammatory cell infiltration developed at 4 and 8 weeks in BN and Wistar rats, respectively, and formation of pseudolobules was detected at 8 weeks in rats of both strains. The expression of liver TIMP-1 and -2 mRNAs significantly increased at 8 weeks in rats of both strains. At the same time, TIMP-1 and -2 activities were also detected in the liver of both strains. On the other hand, the expression of serum TIMP-1 and -2 proteins increased earlier (at 4 weeks for TIMP-1 and at 2 or 4 weeks for TIMP-2) than that of liver TIMP-1 and -2 mRNAs did. Although there are some reports suggestive of why the elevation of serum TIMP-1 and -2 proteins preceded that of liver TIMP-1 and -2 mRNAs, the exact reason is still obscure. In conclusion, the present study showed for the first time the mode of TIMP-1 and -2 expression and activity in the early stage of PS-induced rat liver fibrosis model.

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.

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.

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).

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

Leptin is recognized as a profibrogenic hormone in the liver, but the mechanisms involved have not been clarified. The tissue inhibitor of metalloproteinase (TIMP)-1, which acts through inhibition of collagen degradation, is synthesized by activated hepatic stellate cells (HSC) in response to fibrogenic substances. The capacity of leptin to induce TIMP-1 and its signaling molecules were investigated in a human HSC cell line, LX-2. Leptin stimulated TIMP-1 protein, mRNA, and promoter activity. JAK1 and -2, as well as STAT3 and -5, were activated. After leptin, there was increased expression of tyrosine 1141-phosphorylated leptin receptor, which may contribute to STAT3 activation. AG 490, a JAK inhibitor, blocked JAK phosphorylation with concomitant inhibition of STAT activation, TIMP-1 mRNA expression, and promoter activity. Leptin also induced an oxidative stress, which was inhibited by AG 490, indicating a JAK mediation process. ERK1/2 MAPK and p38 were activated, which was prevented by catalase, indicating an H2O2-dependent mechanism. Catalase treatment resulted in total suppression of TIMP-1 mRNA expression and promoter activity. SB203580, a p38 inhibitor, prevented p38 activation and reduced TIMP-1 message half-life with down-regulation of TIMP-1 mRNA. These changes were reproduced by overexpression of the dominant negative p38alpha and p38beta mutants. PD098059, an ERK1/2 inhibitor, opposed ERK1/2 activation and TIMP-1 promoter activity, leading to TIMP-1 mRNA down-regulation. Thus, leptin has a direct action on liver fibrogenesis by stimulating TIMP-1 production in activated HSC. This process appears to be mediated by the JAK/STAT pathway via the leptin receptor long form and the H2O2-dependent p38 and ERK1/2 pathways via activated JAK.

To review the medical literature regarding the histopathologic and biochemical liver test abnormalities in chronic asymptomatic or oligosymptomatic alcoholics.

Review of articles in the MEDLINE and LILACS databases regarding serum levels and prevalence of alterations in aspartate-aminotransferase, alanine-aminotransferase, alkaline phosphatase, and total bilirubin, in relation to liver histopathology, with or without discrimination of types of histopathologic alteration.

Global mean prevalence rates of aspartate-aminotransferase and alanine-aminotransferase alterations were 86.3% and 51.1%; in cases with steatosis they were 79.1% and 38.5%; and in cases of hepatitis, 90.1% and 58%. In all studies, prevalence rates of aspartate-aminotransferase alterations were significantly higher with lower variability than those of alanine-aminotransferase. Mean aspartate-aminotransferase levels were higher than 2N (N is the upper normal limit of the method employed) in all cases with hepatitis histopathology, while those of alanine-aminotransferase were 1.48N, in the same cases. Prevalence of alkaline phosphatase and total bilirubin abnormalities were 74.5% and 74.9% globally; in cases of steatosis, they were 70.9% and 67.9%; and in cases of hepatitis, 75.9% and 77.7%. Mean alkaline phosphatase levels were above the upper normal limit in all cases, but those of total bilirubin were above normal in 4 of 7 hepatitis studies.

Prevalence of aspartate-aminotransferase alteration was consistently related to presence of histopathologic abnormalities; an enzyme level higher than 2N suggests the diagnosis of alcoholic hepatitis.

This study was designed to document noninvasively the pathological mechanisms responsible for myocardial fibrosis and to assess the clinical utility of plasma markers of collagen synthesis and degradation as screening tools for the assessment of fibrosis in hypertension. We studied 100 never-treated hypertensive patients and 50 normal subjects. Echocardiographic assessment was made of left ventricular (LV) mass and diastolic filling using measurement of E:A ratio, E wave deceleration time (E dec), and isovolumic relaxation time (IVRT). The presence of diastolic dysfunction was taken as a surrogate marker for the presence of myocardial fibrosis. Plasma carboxy-terminal propeptide of collagen type I (PICP), carboxy-terminal telopeptide of collagen type I (CITP), and tissue inhibitor of matrix metalloproteinases type I (TIMP-1) were measured as markers of collagen synthesis, degradation, and inhibition of degradation, respectively. Plasma TIMP-1 was significantly elevated in the hypertensive cohort (358 ng/mL versus 253 ng/mL, P<0.001) as were CITP (5.2 microg/L versus 2.9 microg/L, P<0.001), and PICP (200 microg/L versus 166 microg/L, P<0.05). TIMP-1 was significantly elevated in patients with diastolic dysfunction (421 ng/mL versus 283 ng/mL P<0.01) and correlated with markers of diastolic filling, namely E:A ratio (r=0.26, P<0.05) and E Dec (r=0.41, P<0.01). A plasma TIMP-1 level of >500 ng/mL had a specificity of 97% and a positive predictive value of 96% in predicting diastolic dysfunction. In patients with untreated hypertension, there is evidence of increased collagen synthesis, degradation, and inhibition of degradation resulting in fibrosis. Our results demonstrate that plasma TIMP-1 correlates with markers of LV diastolic filling, is predictive of LV dysfunction, and is a potential noninvasive marker of fibrosis.

Acute alcohol withdrawal causes changes in hepatic blood flow and metabolism that may result in liver damage. This study aims to assess liver function tests and markers of hepatic fibrogenesis following alcohol withdrawal in alcoholics with clinically compensated liver disease.

Serial liver function tests and clinical assessments were performed on 22 male alcoholics during alcohol withdrawal. Plasma tissue inhibitor of metalloproteinase 1 (TIMP1), an inhibitor of collagen degradation, and plasma amino-terminal procollagen III peptide (PIIINP), a collagen precursor molecule, were measured in these alcoholics and in 11 control subjects.

Transaminase levels did not change significantly over 7 days when all subjects were analyzed together. However, 32% of subjects showed a marked transaminase rise. These subjects did not differ from the others in baseline characteristics or short-term outcome, but had a greater benzodiazepine requirement. Only one subject consumed paracetamol (acetaminophen; 1-2 g/day). He had the largest transaminase rise. By comparing PIIINP assays, intact PIIINP concentration appears to increase following alcohol withdrawal. The TIMP1 levels were elevated in alcoholic subjects, but did not change following withdrawal.

Increasing PIIINP suggests that hepatic fibrogenesis increases, or hepatic clearance falls, during acute alcohol withdrawal. The TIMP1 elevation in these alcoholics suggests that the inhibition of collagen degradation occurs while liver disease is still compensated. The period following alcohol withdrawal may be a time of marked increased susceptibility to paracetamol. The biochemical changes we observed were not associated with adverse short-term outcome, but the cumulative effect after repeated episodes of abrupt withdrawal may be of concern.

It has been suggested that left ventricular fibrosis in spontaneously hypertensive rats (SHR) is the result of both exaggerated collagen synthesis and insufficient collagen degradation. We have shown previously that chronic treatment with the angiotensin II type 1 receptor antagonist losartan results in diminished synthesis of collagen type I molecules and reversal of myocardial fibrosis in SHR. This study was designed to investigate whether losartan also affects the extracellular degradation of collagen type I fibers in the left ventricle of SHR. The study was performed in 30-week-old normotensive Wistar-Kyoto rats (WKY), untreated SHR, and SHR treated with orally administered losartan (20 mg/kg per day) for 14 weeks before they were killed. Ventricular collagenase activity was determined by degradation of [(14)C]collagen with tissue extracts. Ventricular expression of tissue inhibitor of metalloproteinases 1 (TIMP-1) mRNA was analyzed by Northern blot. A histomorphometric study of the left ventricle was performed in all rats. Compared with WKY, SHR exhibited left ventricular hypertrophy, increased (P<0.05) blood pressure, left ventricular collagen volume fraction and TIMP-1 mRNA, and diminished (P<0.05) collagenase activity. After the treatment period, blood pressure was higher (P<0.05) in losartan-treated SHR than in WKY, and no significant differences were noted in the remaining parameters between the 2 strains of rats. Compared with untreated SHR, treated SHR showed no left ventricular hypertrophy, diminished (P<0.05) blood pressure, left ventricular collagen volume fraction and TIMP-1 mRNA, and increased (P<0.05) collagenase activity. These results suggest that the transcription of the TIMP-1 gene is upregulated in the hypertrophied and fibrotic left ventricle of adult SHR. Upregulation of TIMP-1 may account for diminished collagenase activity in the myocardium of those rats. Chronic angiotensin II type 1 receptor blockade with losartan resulted in inhibition of TIMP-1 expression and stimulation of collagenase activity in the left ventricle of SHR. It is proposed that angiotensin II may facilitate myocardial fibrosis in SHR by depressing the collagenase-mediated extracellular degradation of collagen fibers.

Enhanced expression of the type IV collagenases MMP-2 and MMP-9, or lack of their inhibitors TIMP-1 and TIMP-2, has been associated with tumour invasion and metastatic potential in several experimental models. Regulation of enzyme activity is clearly a key step in tumour invasion, and recently a potent activator of MMP-2, the membrane-associated MT1-MMP, has been described and characterized. Using an immunohistochemical approach, this study has examined the expression and distribution of the type IV collagenases, their inhibitors, and the activator MT1-MMP, in a series of 79 infiltrating ductal carcinomas (IDCs), 8 tubular carcinomas, and 27 infiltrating lobular carcinomas (ILCs). MMP-2 and MT1-MMP were expressed in more than 90 per cent of all carcinomas, with predominantly stromal and tumour cell cytoplasmic staining. However, reactivity localized on tumour cell membranes was recorded for MMP-2 in 34 per cent of cases with a monoclonal antibody and 55 per cent of cases with a polyclonal antibody, and for MT1-MMP in 68 per cent of tumours. In each case, this pattern of staining was significantly associated with the presence of lymph node metastasis (p=0.001, p=0. 008, and p=0.1, respectively). Both tumour cell and stromal staining was observed for TIMP-2, but there was no correlation with metastatic status. The 92 kD gelatinase MMP-9 was expressed by 68 per cent of carcinomas, either in the stromal compartment or by tumour cells. There was a highly significant correlation between the expression pattern of MMP-9 and tumour type, with ILCs displaying greater frequency and more homogeneous cytoplasmic staining than IDCs (p=0.0004). Staining for TIMP-1 was seen in the stroma and also in relation to small blood vessels, with more than 90 per cent of tumours showing this staining pattern using a polyclonal antibody. This study indicates distinct patterns of expression for different MMPs and demonstrates the potential importance of the MMP-2/MT1-MMP system in breast tumour progression. The association of MMP-9 with the infiltrating lobular phenotype may reveal novel mechanisms of control for this metalloproteinase.

Elevated plasma levels of homocysteine have been shown to interfere with normal cell function in a variety of tissues and organs, such as the vascular wall and the liver. However, the molecular mechanisms behind homocysteine effects are not completely understood. In order to better characterize the cellular effects of homocysteine, we have searched for changes in gene expression induced by this amino acid. Our results show that homocysteine is able to induce the expression and synthesis of the tissue inhibitor of metalloproteinases-1 (TIMP-1) in a variety of cell types ranging from vascular smooth muscle cells to hepatocytes, HepG2 cells and hepatic stellate cells. In this latter cell type, homocysteine also stimulated alpha 1(I) procollagen mRNA expression. TIMP-1 induction by homocysteine appears to be mediated by its thiol group. Additionally, we demonstrate that homocysteine is able to promote activating protein-1 (AP-1) binding activity, which has been shown to be critical for TIMP-1 induction. Our findings suggest that homocysteine may alter extracellular matrix homeostasis on diverse tissular backgrounds besides the vascular wall. The liver could be considered as another target for such action of homocysteine. Consequently, the elevated plasma levels of this amino acid found in different pathological or nutritional circumstances may cooperate with other agents, such as ethanol, in the onset of liver fibrosis.

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.

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.

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.

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.

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.

A rat model of common bile duct ligation (BDL)-induced hepatic fibrosis was used to assess the expression and activities of collagen-degrading proteinases and their inhibitors during the progression of fibrosis. Expression of four members of the matrix metalloproteinase (MMP) family (MMP-2/gelatinase A, MMP-3, MMP-9/gelatinase B, and MMP-13) and three tissue inhibitors of metalloproteinases-1, -2, and -3 (TIMP-1, TIMP-2, and TIMP-3) were evaluated by Northern blot analysis of RNA from liver tissue isolated at 0, 2, 5, 10, 20, and 30 days after either a BDL or sham operation. In addition, we analyzed free gelatinase and TIMP activities by zymography and reverse zymography, respectively. We found that the proteolytic activities of MMP-2 and MMP-9 increased by 2 days after ligation, reached maximal levels at day 10, and remained high through the study period, whereas the gelatinolytic activities in plasma were unchanged. The increase in gelatinase activities was accompanied by an increase in the TIMP mRNA transcripts. TIMP-1 transcripts appeared at day 2, increased until day 10, and remained elevated throughout the study period. TIMP-2 and TIMP-3 transcripts become detectable on day 10 and remained stable afterwards. No corresponding increase in TIMP protein activity was detected by reverse zymography. This appears to result from the formation of TIMP/MMP complexes. These findings indicate a likely surplus in the BDL model of fibrosis of free gelatinases as compared with the TIMPs. Thus, excessive TIMP production is not a sufficient explanation for the observed extracellular matrix accumulation, but complex changes in the local MMP/TIMP balance may underlie the pathomechanisms of fibrosis.

This study was designed to investigate whether collagen type I degradation is altered in patients with essential hypertension and whether this alteration could be related to disturbances in the serum matrix metalloproteinase pathway of collagen degradation. A second aim of the study was to assess whether some relation exists between serum markers of collagen type I degradation and left ventricular hypertrophy in hypertensive patients.

We measured serum concentrations of carboxy-terminal telopeptide of collagen type I (CITP) as a marker of extracellular collagen type I degradation, of total matrix metalloproteinase-1 (MMP-1), or collagenase, of total tissue inhibitor of metalloproteinases 1 (TIMP-1), and of MMP-1/TIMP-1 complex in 37 patients with never-treated essential hypertension and in 23 normotensive control subjects. Serum concentrations of free MMP-1 and free TIMP-1 were calculated by subtracting the values of MMP-1/TIMP-1 complex from the values of total MMP-1 and total TIMP-1, respectively. Measurements were repeated in 26 hypertensive patients after 1 year of treatment with the ACE inhibitor lisinopril. Baseline free MMP-1 was decreased (P<0.001) and baseline free TIMP-1 was increased (P<0.001) in hypertensives compared with normotensives. No significant differences were observed in the baseline values of CITP between the 2 groups of subjects. Hypertensive patients with baseline left ventricular hypertrophy exhibited lower values of free MMP-1 (P<0.01) and CITP (P<0.05) and higher (P<0.001) values of free TIMP-1 than hypertensive patients without baseline left ventricular hypertrophy. Treated patients attained an increase (P<0.001) in free MMP-1 and a decrease (P<0.05) in free TIMP-1. In addition, serum CITP was increased (P<0.05) in treated hypertensives compared with normotensive subjects.

These findings suggest that systemic extracellular degradation of collagen type I is depressed in patients with essential hypertension and can be normalized by treatment with lisinopril. A depressed degradation of collagen type I may facilitate organ fibrosis in hypertensive patients, namely, in those with left ventricular hypertrophy.

Serum levels of tissue inhibitor of metalloproteinases-2 (TIMP2) and of precursor form of matrix metalloproteinase-2 (proMMP2) were determined in patients with chronic hepatitis and hepatocellular carcinoma by a one-step sandwich enzyme immunoassay. Serum levels of TIMP2 and proMMP2 were significantly higher in patients with chronic liver disease, than in normal controls. Serum levels of TIMP2 showed a weak negative correlation with the serum albumin level and prothrombin time (PT). Serum levels of proMMP2 in patients with chronic hepatitis were strongly correlated with those of type IV collagen and were negatively correlated with PT and serum albumin levels. Serum proMMP2 levels were also significantly correlated with histological stages. These data indicate that serum levels of proMMP2 might be useful in the follow-up of patients with chronic hepatitis.

Tissue inhibitor of metalloproteinase (TIMP)-1 is an important regulator of matrix metalloproteinase activity. To clarify the changes in TIMP-1 in diseased livers, we measured TIMP-1 concentrations in liver tissue samples from patients with chronic liver disease. The relationship between serum and liver levels of TIMP-1 was also examined in some patients.

The subjects were 68 patients who underwent liver biopsy. The liver TIMP-1 concentration was measured using an enzyme immunoassay after the extraction of TIMP-1 with 2 M guanidine.

As compared with the controls (n=10), the liver TIMP-1 level was increased 2.2-fold in the 24 chronic active hepatitis 2A patients, 2.9-fold in the 10 chronic active hepatitis 2B patients and 4.1-fold in the six liver cirrhosis patients, but no significant increase was observed among the 18 chronic persistent hepatitis patients. The liver TIMP-1 levels were closely correlated with the histological degrees of periportal necrosis, portal inflammation, and liver fibrosis. When the localization of TIMP-1 was examined immunohistochemically, TIMP-1 was stained mainly in hepatocytes, and the intensity was stronger in the livers of chronic active hepatitis and liver cirrhosis patients than in those of the chronic persistent hepatitis patients. The serum TIMP-1 and liver TIMP-1 levels were significantly correlated, indicating that serum TIMP-1 could reflect the change of liver TIMP-1 in patients with chronic liver disease.

Liver TIMP-1 concentration increases with progression of the liver disease, when the degradation of extracellular matrix proteins is decreased, resulting in the development of liver fibrosis.

We analyzed blood plasma concentrations of matrix metalloproteinase-1 and -3 (MMP-1; MMP-3), the tissue inhibitor of metalloproteinase-1 (TIMP-1) and the complex MMP-1/TIMP-1, and looked for any correlation with prostate cancer stage. These components were measured by ELISA tests specific for these proteins in healthy male controls (n = 35), and in patients with benign prostatic hyperplasia (BPH; n = 29), with prostate cancer (PCa) without metastasis (T2,3pN0M0; n = 29) and with PCa with metastatic disease (T2,3,4pN1,2M1; n = 18). Mean values of MMP-1 and of the complex MMP-1/TIMP-1 were not different among the 4 groups studied. The mean MMP-3 and especially TIMP-1 concentrations were significantly higher in PCa patients with metastases compared with controls, BPH and PCa patients without metastases. Ten of these 18 patients had TIMP-1 concentrations higher than the upper reference limit. TIMP-1 concentrations were correlated with staging but not with grading. Our results point towards plasma TIMP-1 concentration as a potential marker of malignant progression of PCa.

The imbalance between matrix metalloproteinases (MMPs) and tissue inhibitors of matrix metalloproteinases (TIMPs) is considered to be an important determinant of extracellular matrix deposition and breakdown. We measured serum MMP-1, MMP-2, TIMP-1 and TIMP-2 levels using the respective one-step sandwich enzyme immunoassays in 98 patients with chronic hepatitis C treated with interferon beta to examine their clinical significance for assessment of liver histology and to determine whether they can be useful as predictors of the interferon response.

Serum TIMP-1 levels showed a positive correlation with the degree of fibrosis (r(s)=0.30, p= 0.004). Serum MMP-2 levels revealed positive relationships with the degree of periportal necrosis (r(s)= 0.32, p=0.002), the degree of fibrosis (r(s)=0.26, p= 0.01) and total score of histological activity index (r(s)=0.24, p=0.02). Serum MMP-2 levels were significantly higher in patients with no response than in those with sustained and transient response (p<0.01 and p<0.05, respectively), while serum MMP-1 levels did not differ among the three groups. Compared with the levels in sustained responders, the total amounts of serum TIMP-1 were significantly lower in transient responders and non-responders (p<0.01 and p<0.001, respectively). As for serum TIMP-2 levels, a significant decrease was found in transient responders and non-responders (p<0.01). The ratios of serum MMP-2 to TIMP-1 levels were significantly higher in transient responders and non-responders than in sustained responders (p<0.001, respectively) even when HCV RNA levels were low in patients with HCV genome subtype 1b or when the HCV genome subtype was 2a or 2b. Sustained response was never found in type 1b patients with ratios of serum MMP-2 to TIMP-1 levels of over 6.0. In logistic multivariate regression analysis, the ratios of serum MMP-2 to TIMP-1 level (p=0.0001), HCV genome subtype (p=0.005) and serum TIMP-2 level (p=0.03) were the independent predictors for sustained response, while serum MMP-2 level (p=0.0006) was the only predictor for no response.

Serum MMP-2 and TIMP-1 levels might be useful for estimating the degree of liver fibrosis. The ratio of serum MMP-2 to TIMP-1 levels may serve as a new predictor of interferon response in patients with chronic hepatitis C.

More than 7 percent of all adults in the United States have met diagnostic criteria for alcohol abuse and alcohol dependence. Many of these people and even occasional users of alcohol may exhibit medical complexities, particularly liver disease, that can adversely affect provision of routine dental care. This article highlights some of the important clinical topics associated with alcoholic liver disease as it relates to dental care and provides guidelines on treatment of affected people.

Although various serum markers for the evaluation of hepatic fibrosis have been introduced, it remains unclear which is the best marker to evaluate the hepatic fibrosis observed in alcoholic liver disease (ALD). In this study, we measured serum concentrations of the immunoreactive beta-subunit of prolyl hydroxylase, procollagen type III peptide, the 7S domain (7S-IV) and triple-helix domain (TH-IV) of type IV collagen, laminin, and tissue inhibitor of metalloproteinase (TIMP) in patients with and without ALD (non-ALD), and controls to evaluate the best serum marker reflecting the characteristic histologic features of ALD. After Azan-Mallory and silver-impregnated reticulin staining, histologic specimens were examined; and the degree of hepatic fibrosis was classified as mild, moderate, or severe. Although serum concentrations of all markers, except for TIMP, in patients with each type and stage of liver disease were higher than cut-off values and these concentrations increases with the progression of liver disease, statistical analyses indicate that serum TH-IV concentration is the best marker to distinguish ALD from non-ALD. A good correlation was also found between the hepatic type IV collagen content and serum TH-IV, but not serum 7S-IV concentration. Moreover, after abstinence from alcohol, serum concentrations of TH-IV decreased more quickly than other serum markers. These results clearly suggest that, compared with other markers, serum concentration of TH-IV may more strongly reflect the histologic features of ALD. However, other serum markers, except for TIMP, may be useful in evaluating the degree of hepatic fibrosis.

This study was performed to assess the significance of elevated serum tissue inhibitor of metalloproteinases-1 concentration in various liver diseases.

Tissue inhibitor of metalloproteinases-1 levels were measured in patients with various liver diseases, and were compared with serum type III procollagen-N-peptide (P III P), type IV collagen and laminin P1 levels, as well as with the histology of liver biopsy specimens.

Mean tissue inhibitor of metalloproteinases-1 levels were significantly higher in subjects with acute viral hepatitis, cirrhosis, alcoholic hepatitis, and alcoholic cirrhosis than in the control group (p < 0.05). Serum tissue inhibitor of metalloproteinases-1 levels in the various liver diseases showed positive correlation with serum type IV collagen, P III P, and laminin P1 levels. Regarding the relationship between tissue inhibitor of metalloproteinases-1 and liver histology, serum tissue inhibitor of metalloproteinases-1 levels correlated with the degree of hepatic fibrosis and inflammation, such as focal necrosis and cell infiltration. Furthermore, elevated serum tissue inhibitor of metalloproteinases-1 levels were especially related to the cell infiltration, focal necrosis, portal fibrosis, and serum type IV collagen level.

These findings suggest that the measurement of the serum tissue inhibitor of metalloproteinases-1 level in various liver diseases may be useful to estimate the active hepatic fibrogenesis associated with the active inflammatory stage of the liver injury.

One of the suggested contributory factors to the development of dermal fibrosis is a decrease in collagenase activity, which may be related to levels of serum tissue inhibitors of metalloproteinase-1 (TIMP-1).

The aim of this study was to determine the clinical significance of serum TIMP-1 levels in systemic sclerosis (SSc).

We measured serum TIMP-1 concentration in 62 patients with SSc, 11 patients with systemic lupus erythematosus, 14 patients with rheumatoid arthritis, and 22 members of a normal control group. The clinical features of the patients with SSc and elevated TIMP levels were examined.

The mean TIMP-1 level in the patients with SSc was significantly higher than that in the members of the control group or the patients with systemic lupus erythematosus or rheumatoid arthritis. In 44% of the patients with SSc the serum TIMP-1 level was elevated. The mean serum TIMP-1 level in patients with diffuse cutaneous SSc (dSSc) was significantly higher than that in those with limited cutaneous SSc. The patients with dSSc and elevated serum TIMP-1 levels showed a significantly greater incidence of lung fibrosis and anti-topoisomerase I antibody than those with normal serum TIMP-1 levels. The TIMP-1 level and diffusing capacity for carbon monoxide in the patients with SSc were negatively correlated. Increased mitogenic activity on dermal fibroblasts caused by serum from patients with dSSc was partially blocked by anti-TIMP-1 IgG.

These findings suggest that serum TIMP-1 level is a useful indicator of disease activity in patients with SSc and that TIMP is involved in the pathogenesis of SSc.

Clinical and pathological differences between chronic hepatitis B and chronic hepatitis C have now been established.

To compare hepatic connective tissue metabolism in chronic hepatitis B and C, we determined serum levels of prolyl 4-hydroxylase beta-subunit, procollagen III aminoterminal peptide, type IV collagen 7S domain, the central helix region of type IV collagen, tissue inhibitor of metalloproteinase, and hyaluronan in 55 patients with chronic hepatitis B and 83 patients with chronic hepatitis C.

There were no significant differences in the above markers for connective tissue turnover between the chronic hepatitis B group and the chronic hepatitis C group.

These results suggest that the accelerated connective tissue metabolism observed in chronic viral hepatitis is independent of the causative virus.

Matrix metalloproteinase-II (MMP-II, 72-kd type IV collagenase, or gelatinase) is one of the gene families of zinc enzymes capable of degrading extracellular matrix molecules, and specifically of degrading type IV and V collagens, gelatin, fibronectin, and elastin. In this study, we used both the liver fibrosis model and the reversibility model of experimental cirrhosis to clarify how MMP-II participates in liver fibrosis of rats. To produce fibrosis model, rats received subcutaneous injections of CCl4 twice weekly for 7, 9, or 14 weeks. For the reversibility model, rats were treated with CCl4 three times a week for 8 weeks and killed at 3, 7, 14, 28, or 42 days after discontinuation of treatment. MMP-II gene expression was studied by Northern hybridization technique, and gelatinase activity of MMP-II was examined by zymography using gelatin substrate. At the same time, an immunohistochemical study using anti-type IV collagen antibody was carried out. In liver fibrosis model, nodule formation was established at 14 weeks. Immunodeposit of type IV collagen was increased in wide fibrous septa and was clearly observed along sinusoidal wall. Gene expression of MMP-II increased up to 7 to 12 times compared with that of controls, with the expression rate being maximum at an intermediate stage of fibrosis. Zymography showed the expressions of both 65-kd latent MMP-II, which is confirmed to be activated by adding p-aminophenylmercuric acetate, and 62-kd active MMP-II during fibrosis. The expression of both forms increased 13 to 28 times as the fibrosis progressed.(ABSTRACT TRUNCATED AT 250 WORDS)

This article reviews current concepts on the pathogenesis and treatment of alcoholic liver disease. It has been known that the hepatotoxicity of ethanol results from alcohol dehydrogenase-mediated excessive generation of hepatic nicotinamide adenine dinucleotide, reduced form, and acetaldehyde. It is now recognized that acetaldehyde is also produced by an accessory (but inducible) microsomal pathway that additionally generates oxygen radicals and activates many xenobiotics to toxic metabolites, thereby explaining the increased vulnerability of heavy drinkers to industrial solvents, anesthetics, commonly used drugs, over-the-counter medications, and carcinogens. The contribution of gastric alcohol dehydrogenase to the first-pass metabolism of ethanol and alcohol-drug interactions is discussed. Roles for hepatitis C, cytokines, sex, genetics, and age are now emerging. Alcohol also alters the degradation of key nutrients, thereby promoting deficiencies as well as toxic interactions with vitamin A and beta carotene. Conversely, nutritional deficits may affect the toxicity of ethanol and acetaldehyde, as illustrated by the depletion in glutathione, ameliorated by S-adenosyl-L-methionine. Other "supernutrients" include polyunsaturated lecithin, shown to correct the alcohol-induced hepatic phosphatidylcholine depletion and to prevent alcoholic cirrhosis in nonhuman primates. Thus, a better understanding of the pathology induced by ethanol is now generating improved prospects for therapy.