An inverse relationship between markers of fibrogenesis and collagen degradation in patients with or without alcoholic liver disease

Patterns of IgA Autoantibody Generation, Inflammatory Responses and Extracellular Matrix Metabolism in Patients with Alcohol Use Disorder

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.

Predictive risk markers in alcoholism

The medical disorders of alcoholism rank among the leading public health problems worldwide and the need for predictive and prognostic risk markers for assessing alcohol use disorders (AUD) has been widely acknowledged. Early-phase detection of problem drinking and associated tissue toxicity are important prerequisites for timely initiations of appropriate treatments and improving patient's committing to the objective of reducing drinking. Recent advances in clinical chemistry have provided novel approaches for a specific detection of heavy drinking through assays of unique ethanol metabolites, phosphatidylethanol (PEth) or ethyl glucuronide (EtG). Carbohydrate-deficient transferrin (CDT) measurements can be used to indicate severe alcohol problems. Hazardous drinking frequently manifests as heavy episodic drinking or in combinations with other unfavorable lifestyle factors, such as smoking, physical inactivity, poor diet or adiposity, which aggravate the metabolic consequences of alcohol intake in a supra-additive manner. Such interactions are also reflected in multiple disease outcomes and distinct abnormalities in biomarkers of liver function, inflammation and oxidative stress. Use of predictive biomarkers either alone or as part of specifically designed biological algorithms helps to predict both hepatic and extrahepatic morbidity in individuals with such risk factors. Novel approaches for assessing progression of fibrosis, a major determinant of prognosis in AUD, have also been made available. Predictive algorithms based on the combined use of biomarkers and clinical observations may prove to have a major impact on clinical decisions to detect AUD in early pre-symptomatic stages, stratify patients according to their substantially different disease risks and predict individual responses to treatment.

Patients With Cirrhosis Have Elevated Bone Turnover but Normal Hepatic Production of Osteoprotegerin

CONTEXT

Severe osteodystrophy is common in patients with liver dysfunction. Markers of bone metabolism may help in early diagnosis of osteodystrophy and in understanding underlying pathophysiological mechanisms.

OBJECTIVE

To elucidate changes in bone metabolism associated with cirrhosis and to determine the route of elimination for the markers.

METHODS

Case-control study at a public university hospital. Fifty-nine patients with cirrhosis (47 alcoholic and 12 nonalcoholic cirrhosis) and 20 controls were included. Participants underwent catheterization of the femoral artery, and the hepatic, renal, and femoral veins with collection of blood from all 4 sites. Regional arteriovenous differences in concentrations of bone metabolism markers were determined: procollagen of type I collagen propeptide (PINP), C-terminal cross-linking telopeptide of type I collagen (CTX), osteocalcin, tartrate-resistant acid phosphatase isoform 5b (TRAcP5b), osteoprotegerin (OPG), and sclerostin and correlated with degree of disease (Child-Pugh classification).

RESULTS

PINP concentration was higher (median: 87.9 µg/L) in patients with cirrhosis than in controls (52.6 µg/L) (P = .001), while hepatic extraction was lower (4.3% vs 14.5%) (P < .001). Both CTX and TRAcP5b were higher in patients with cirrhosis (340 ng/L and 3.20 U/L) than in controls (215 ng/L and 1.60 U/L) (P < .001 and P < .0001). Hepatic sclerostin extraction was lower in patients with cirrhosis (14.6%) than in controls (28.7%) (P < .0001). In both groups OPG showed a hepatic release rate (production) of 6%.

CONCLUSION

Patients with cirrhosis have increased bone resorption, but unaltered bone formation. Sclerostin is eliminated through the liver while OPG is produced in the liver. Bone markers may prove useful in evaluating bone turnover in patients with cirrhosis.

Bone turnover markers in gingival crevicular fluid and blood serum of patients with fixed orthodontic appliances

AIM

Bone remodelling can be followed through the bone turnover markers (BTMs). Aim of the present study was to record the fluctuation of an osteoclastic and an osteoblastic BTM [C-terminal telopeptide of type I collagen (CTX) and N-terminal pro-peptide of type I pro-collagen (PINP), respectively] in both the gingival crevicular fluid (GCF) and the serum of orthodontic patients before and after the initial application of orthodontic forces.

MATERIALS AND METHODS

Twenty-one Caucasian patients were prospectively evaluated. GCF and blood samples were collected in order to measure the selected biomarkers by ELISA at three time-points: exactly before, 5 days, and 14 days after bonding of the appliances. Standardized sample handling and patient preparation procedures were adopted in order to reduce pre-analytical variability.

RESULTS

GCF and serum CTX levels were found to be independent of age, although higher in the serum of female subjects. PINP levels were found higher in the serum of patients ≥25 years old, as well as in the GCF of males. A positive correlation between serum and GCF baseline PINP levels was observed.

LIMITATIONS

The effect of orthodontic treatment on bone remodelling might not be absolutely representative of the local bone microenvironment as the levels of the specific BTMs where measured within the GCF of the lower front teeth.

CONCLUSIONS

This is the first time PINP and CTX have been evaluated in the GCF and serum of orthodontic patients with fixed appliances. No statistically significant alterations of CTX and PINP levels in the GCF and the serum of patients were recorded over time during the initial stages of orthodontic treatment.

Bone Turnover Markers and Probable Advanced Nonalcoholic Fatty Liver Disease in Middle-Aged and Elderly Men and Postmenopausal Women With Type 2 Diabetes

Objective: Type 2 diabetic patients have a higher incidence of nonalcoholic steatohepatitis (NASH) and advanced stages of fibrosis, and nonalcoholic fatty liver disease (NAFLD) is associated with impaired bone health. We aimed to investigate whether bone turnover is associated with the probable presence of NASH and fibrosis. Methods: In total, 4,937 diabetic participants from Shanghai, China were enrolled in 2018. Subjects with NAFLD were categorized into simple NAFLD and probable NASH groups based on the presence of a metabolic syndrome. The NAFLD fibrosis score was used to identify patients with a higher likelihood of advanced fibrosis. Results: In postmenopausal women, large N-mid fragment of osteocalcin (N-MID osteocalcin) was negatively associated with probable NASH (P for trend < 0.001). β-C-terminal cross-linked telopeptides of type I collagen (β-CTX) and procollagen type I N-terminal propeptide (P1NP) were positively associated with the probable presence of significant fibrosis in postmenopausal women (P for trend 0.015 and <0.001). However, in men, N-MID osteocalcin and β-CTX were negatively associated with the probable presence of significant fibrosis (P for trend 0.029 and 0.027). Conclusions: Significant associations among N-MID osteocalcin, β-CTX and P1NP, and probable advanced NAFLD were observed. Further prospective and animal studies are warranted to understand the causal relationship and underlying mechanism.

Use of CTX-I and PINP as bone turnover markers: National Bone Health Alliance recommendations to standardize sample handling and patient preparation to reduce pre-analytical variability

The National Bone Health Alliance (NBHA) recommends standardized sample handling and patient preparation for C-terminal telopeptide of type I collagen (CTX-I) and N-terminal propeptide of type I procollagen (PINP) measurements to reduce pre-analytical variability. Controllable and uncontrollable patient-related factors are reviewed to facilitate interpretation and minimize pre-analytical variability.

INTRODUCTION

The IOF and the International Federation of Clinical Chemistry (IFCC) Bone Marker Standards Working Group have identified PINP and CTX-I in blood to be the reference markers of bone turnover for the fracture risk prediction and monitoring of osteoporosis treatment. Although used in clinical research for many years, bone turnover markers (BTM) have not been widely adopted in clinical practice primarily due to their poor within-subject and between-lab reproducibility. The NBHA Bone Turnover Marker Project team aim to reduce pre-analytical variability of CTX-I and PINP measurements through standardized sample handling and patient preparation.

METHODS

Recommendations for sample handling and patient preparations were made based on review of available publications and pragmatic considerations to reduce pre-analytical variability. Controllable and un-controllable patient-related factors were reviewed to facilitate interpretation and sample collection.

RESULTS

Samples for CTX-I must be collected consistently in the morning hours in the fasted state. EDTA plasma is preferred for CTX-I for its greater sample stability. Sample collection conditions for PINP are less critical as PINP has minimal circadian variability and is not affected by food intake. Sample stability limits should be observed. The uncontrollable aspects (age, sex, pregnancy, immobility, recent fracture, co-morbidities, anti-osteoporotic drugs, other medications) should be considered in BTM interpretation.

CONCLUSION

Adopting standardized sample handling and patient preparation procedures will significantly reduce controllable pre-analytical variability. The successful adoption of such recommendations necessitates the close collaboration of various stakeholders at the global stage, including the laboratories, the medical community, the reagent manufacturers and the regulatory agencies.

Biomarker-Based Approaches for Assessing Alcohol Use Disorders

Although alcohol use disorders rank among the leading public health problems worldwide, hazardous drinking practices and associated morbidity continue to remain underdiagnosed. It is postulated here that a more systematic use of biomarkers improves the detection of the specific role of alcohol abuse behind poor health. Interventions should be initiated by obtaining information on the actual amounts of recent alcohol consumption through questionnaires and measurements of ethanol and its specific metabolites, such as ethyl glucuronide. Carbohydrate-deficient transferrin is a valuable tool for assessing chronic heavy drinking. Activities of common liver enzymes can be used for screening ethanol-induced liver dysfunction and to provide information on the risk of co-morbidities including insulin resistance, metabolic syndrome and vascular diseases. Conventional biomarkers supplemented with indices of immune activation and fibrogenesis can help to assess the severity and prognosis of ethanol-induced tissue damage. Many ethanol-sensitive biomarkers respond to the status of oxidative stress, and their levels are modulated by factors of life style, including weight gain, physical exercise or coffee consumption in an age- and gender-dependent manner. Therefore, further attention should be paid to defining safe limits of ethanol intake in various demographic categories and establishing common reference intervals for biomarkers of alcohol use disorders.

Serum soluble urokinase plasminogen activator receptor in alcoholics: relation to liver disease severity, fibrogenesis, and alcohol use

BACKGROUND AND AIM

Heavy alcohol consumption may lead to development of liver disease and the need for non-invasive parameters for detecting those at risk is widely acknowledged.

METHODS

We measured serum soluble urokinase-type plasminogen activator receptor (suPAR) levels from 63 patients with alcoholic liver disease (ALD), 57 heavy drinkers without apparent liver disease, and 39 controls who were either moderate drinkers or abstainers.

RESULTS

The highest serum suPAR concentrations were detected in patients with ALD (P < 0.001) showing high diagnostic accuracy in differentiating ALD patients from heavy drinkers without liver disease (area under curve 0.921, P < 0.001). Levels of suPAR correlated positively with serum markers of fibrogenesis (aminoterminal propeptide of type III procollagen and hyaluronic acid) (P < 0.001), with clinical (combined clinical and laboratory index P < 0.01) and morphological (combined morphological index P < 0.05) indices of liver disease severity and with the stage of fibrosis (P < 0.01). The suPAR concentrations were also elevated in heavy drinkers when compared with healthy controls (P < 0.001).

CONCLUSION

The data indicate that serum suPAR concentrations are increased as a result of heavy alcohol consumption and further with development of ALD, showing a good diagnostic performance in detecting those with liver disease. The association with the histological severity of ALD and correlation with fibrosis indicates potential of serum suPAR also as a prognostic marker in ALD.

Biomarkers of liver fibrosis

Liver fibrosis is the final common pathway for almost all causes of chronic liver injury. Liver fibrosis is now known to be a dynamic process having significant potential for resolution. Therefore, fibrosis prediction is an essential part of the assessment and management of patients with chronic liver disease. As such, there is strong demand for reliable liver biomarkers that provide insight into disease etiology, diagnosis, therapy, and prognosis in lieu of more invasive approaches such as liver biopsy. Current diagnostic strategies range from use of serum biomarkers to more advanced imaging techniques including transient elastography and magnetic resonance imaging. In addition to these modalities, there are other approaches including the use of novel, but yet to be validated, biomarkers. In this chapter, we discuss the biomarkers of liver fibrosis including the use of invasive and noninvasive biomarkers and disease-specific biomarkers in various chronic liver diseases.

Validation of terminal peptide of procollagen III for the detection and assessment of nonalcoholic steatohepatitis in patients with nonalcoholic fatty liver disease

Liver biopsy is the reference standard for the detection of nonalcoholic steatohepatitis (NASH) within nonalcoholic fatty liver disease (NAFLD). The aim of this study was to identify a biomarker of NASH in patients without significant fibrosis. In all, 172 patients from two centers with biopsy-proven NAFLD were included in this study. Eighty-four patients from a single center were included as a derivation cohort and 88 patients from a second center were included as a validation cohort. Serum samples were tested for candidate markers of fibrosis and inflammation alongside hematological and biochemical markers. Among patients without advanced fibrosis, terminal peptide of procollagen III (PIIINP) was the only marker found to be associated with a histological diagnosis of NASH in both cohorts. PIIINP also correlated with the total NAFLD activity score (NAS) and its constituent components (P < 0.001). Area under receiver operating characteristic curve (AUROC) for PIIINP in discriminating between NASH and simple steatosis (SS) was 0.77-0.82 in patients with F0-2 fibrosis and 0.82-0.84 in patients with F0-3 fibrosis. PIIINP was elevated in patients with advanced fibrosis, the overwhelming majority of whom had NASH. When incorporating patients with all degrees of fibrosis from both cohorts, PIIINP was able to discriminate between patients with SS and those with NASH or advanced fibrosis with AUROC 0.85-0.87.

CONCLUSION

PIIINP discriminates between SS and NASH or advanced fibrosis. The use of a single biomarker in this context will be of clinical utility in detecting the minority of patients with NAFLD who have NASH or advanced fibrosis related to NASH.

Acupuncture Combined with Curcumin Attenuates Carbon Tetrachloride-Induced Hepatic Fibrosis in Rats

Background

Increasingly, studies demonstrate the effectiveness of acupuncture therapy against liver fibrosis. Curcumin is a natural product with antifibrotic effects, but has poor pharmacokinetic profiles. This study aimed to evaluate whether acupuncture combined with curcumin could more potently attenuate liver fibrosis in chemical intoxicated rats.

Methods

60 Sprague–Dawley male rats were randomly divided into control, model, sham, acupuncture, curcumin and combination therapy groups. During the establishment of fibrosis using carbon tetrachloride (CCl4), acupuncture at LR3, LR14, BL18 and ST36 and/or curcumin treatment by mouth were performed simultaneously. After treatment, pathological indexes and histology for hepatic injury and fibrogenesis were detected. The expression of extracellular matrix (ECM) components was also determined.

Results

Acupuncture combined with curcumin potently protected the liver from CCl4-induced injury and fibrogenesis, as indicated by reduced levels of serum aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, hyaluronic acid, laminin and procollagen III. Combined use also led to significant liver histological improvements. Furthermore, combined use effectively inhibited ECM expression such as α-smooth muscle actin, fibronectin and α1(1) collagen.

Conclusions

Acupuncture treatment could significantly enhance the antifibrotic efficacy of curcumin on CCl4-induced hepatic fibrosis in rats in vivo, suggesting that a combination of acupuncture with curcumin may be exploited for the prevention of hepatic fibrosis.

Measurement of aminoterminal propeptide of type I procollagen (PINP) in serum

The aminoterminal propeptide of type I procollagen (PINP) in serum is a sensitive indicator of the synthesis of type I collagen. Four assays are available for PINP, two of them (intact PINP assays) measure the intact propeptide and the other two (total PINP assays) also detect a smaller antigen in serum. In many clinical situations, these assays give similar information, but renal insufficiency increases the concentration of the smaller antigen, influencing both the apparent concentration of PINP and assay calibration. Serum PINP is mostly affected by changes in bone metabolism. In infants and children, the concentration is much higher than in adults. Serum PINP (s-PINP) is a useful indicator of disease activity in Paget's disease of bone, in bone metastases of osteoblastic nature, and in the follow-up of treatment of osteoporosis. The IFCC and IOF recently recommended the use of s-PINP as a reference marker for bone formation in studies concerning fracture risk assessment and treatment response.

Recent clinical and experimental advances in atrial fibrillation

Atrial fibrillation (AF) is the most common arrhythmia in clinical settings (Fuster et al., 2001), and it is often associated with congestive heart diseases (Issac et al., 2007). Many studies in both laboratory and clinical settings have sought to analyze the mechanisms of AF, develop treatments based on these mechanisms, and examine atrial remodeling in chronic AF. The aim of this paper is to analyze recent findings regarding the atrial remodeling that occurs in AF. In particular, we will describe the electrical and structural changes that involve atrial myocytes and the extracellular matrix. We will also describe the general classification and basic pathophysiology of AF and its surgical treatments.

Biomarkers of alcohol consumption and related liver disease

Abstract Alcohol abuse is a major cause of abnormal liver function throughout the world. While measurements of liver enzyme activities (GGT, ALT, AST) are important screening tools for detecting liver disease, due to lack of ethanol-specificity and inconsistencies regarding the definitions of significant alcohol consumption, several other blood tests are usually needed to exclude competing and co-existing causes of abnormal liver function. Information on the specific role of ethanol consumption behind hepatotoxicity may be obtained through measurements of blood ethanol and its specific metabolites (ethyl glucuronide, phosphatidylethanol, protein-acetaldehyde condensates and associated autoimmune responses). Recent studies have indicated that being overweight is another increasingly common cause of abnormal liver enzyme levels and adiposity may also increase the impact of ethanol consumption on liver pathology. Interestingly, increased liver enzyme activities in circulation may reflect not only hepatic function but can also serve as indicators of general health and the status of oxidative stress in vivo. ALT and GGT activities predict insulin resistance, metabolic syndrome, mortality from coronary heart diseases and even mortality from all causes. If the upper reference limits for liver enzyme activities were defined based on the data obtained from normal weight abstainers, the clinical value of liver enzyme measurements as screening tools and in patient follow-up could be significantly improved.

Immunologic mechanism in antifibrotic action of Mushu capsule in rats

AIM: To investigate the immunologic mechanism underlying the antifibrotic action of Mushu capsule in rats with hepatic fibrosis.

METHODS: A hepatic fibrosis model was induced by subcutaneous injection of carbon tetrachloride (CCl4). Wister rats were randomly divided into 4 groups: normal control group, model group, Mushu capsule (MC) group and Biejia Ruangan tablet (BRT) group. MC group and BRT group were subdivided into prevention group and treatment group. Liver sections were stained with HE and Masson respectively for pathological examination. Serum interleukin-2, -6, -8 (IL-2, 6, 8) and tumor necrosis factor-α (TNF-α) levels were determined by radioimmunoassay. The levels of CD4 and CD8 cells were measured by flow cytometry.

RESULTS: IL-2 and IL-6 levels were not obviously different between MC group and BRT group, but IL-8 level in MC groups was markedly lower than that in BRT groups (preventing group: 0.4 ± 0.2 mg/L vs 0.6 ± 0.1 mg/L; treatment group: 0.5 ± 0.2 mg/L vs 0.6 ± 0.2 mg/L, both P < 0.05). MC was superior to BRT in preventing serum TNF-α elevation (1.1 ± 0.3 mg/L vs 1.4 ± 0.3 mg/L, P < 0.05). The decreased serum CD4 and CD4/CD8 levels were markedly raised in MC preventing groups and treatment group (CD4: 36.4% ± 7.5%, 34.6% ± 5.0% vs 28.0% ± 5.1%; CD4/CD8: 1.9% ± 0.4%, 1.8% ± 0.3% vs 1.5% ± 0.2%, all P < 0.01) in comparison with those in model group. The decreased serum CD4 level was markedly raised in BRT preventing group (33.4% ± 4.9% vs 28.0% ± 5.1%, P < 0.05), while there was no difference in BRT treatment group. BRT up-regulated the levels of serum CD8 and CD4/CD8 cells without significant differences. The levels of CD4, CD8 and CD4/CD8 cells had no notable difference between MC group and BRT group.

CONCLUSION: Mushu capsule can regulate the humoral immunity in rats with liver fibrosis by elevating serum IL-2 and decreasing serum IL-6, IL-8 and TNF-α. Simultaneously, it can up-regulate the levels of CD4 and CD4/CD8.

Atrial extracellular matrix remodelling in patients with atrial fibrillation

Atrial fibrillation (AF) is the most frequent clinical arrhythmia. Atrial fibrosis is an important factor in initiating and maintaining AF. However, the collagen turnover and its regulation in AF has not been completely elucidated. We tested the hypothesis that the extracellular matrix changes are more severe in patients with permanent AF in comparison with those in patients in sinus rhythm (SR). Intraoperative biopsies from the right atrial appendages (RAA) and free walls (RFW) from 24 patients with AF undergoing a mini-Maze procedure and 24 patients in SR were investigated with qualitative and quantitative immunofluorescent and Western blot analyses. As compared with SR, all patients with AF exhibited dysregulations in collagen type I and type III synthesis/degradation. Tissue inhibitors of metalloproteinases (TIMP2) was significantly enhanced only in RAA-AF. As compared with SR, collagen VI, matrix metalloproteinases MMP2, MMP9 and TIMP1 were significantly increased while TIMP3 and TIMP4 remained unchanged in all AF groups. Reversion-inducing cysteine-rich protein with Kazal motifs (RECK), a newly discovered MMPs inhibitor, was elevated in RFW as compared to RAA-AF (P<0.05) and RFW-SR (P<0.05). The level of transforming growth factor (TGF)-β1 was higher in AF than SR. Smad2 and phosphorylated Smad2 showed an elevation in RFW-AF as compared to RFW-SR, RAA-AF, and RAA-SR groups (P<0.05). Conclusions: Atrial fibrosis in AF is characterized by severe alterations in collagen I and III synthesis/degradation associated with disturbed MMP/TIMP systems and increased levels of RECK. TGF-β1 contributes to atrial fibrosis via TGF-β1-Smad pathway by phospho-rylating Smad2. These processes culminate in accumulations of fibrillar and non-fibrillar collagens leading to excessive atrial fibrosis and maintainance of AF.