Hepatocyte production of modulators of extracellular liver matrix in normal and cirrhotic rat liver

Nobiletin Alleviated Epithelial-Mesenchymal Transition of Hepatocytes in Liver Fibrosis Based on Autophagy-Hippo/YAP Pathway

SCOPE

The current researches indicated that the epithelial-mesenchymal transition (EMT) of hepatocytes plays a crucial role in the development of liver fibrosis. To date, there is a paucity of literature regarding the impact of nobiletin (NOB) on liver fibrosis. This study investigates the inhibitory effect of NOB on EMT in hepatocytes during the progression of liver fibrosis and its underlying mechanism.

METHODS AND RESULTS

The findings demonstrated that NOB significantly suppresses liver fibrosis in carbon tetrachloride (CCl4 )-induced mice by reducing inflammation and fiber deposition in the liver. Moreover, NOB mitigates EMT in hepatocytes, concurrently alleviating inflammatory status and reducing the production of reactive oxygen species (ROS) generation. The comprehensive investigation reveals that the hepatoprotective effect of NOB in liver fibrosis is attributed to autophagy activation, as evidenced by a significant increase in LC3 II expression and p62 degradation upon NOB treatment. Additionally, NOB activates the Hippo/YAP pathway by downregulating YAP and its downstream targets in liver fibrosis, which is regulated by autophagy based on experiments with chloroquine (CQ), 3-methyladenine (3-MA), and siYAP intervention.

CONCLUSION

Therefore, this study provides evidences that NOB can protect hepatocytes from undergoing EMT during liver fibrosis by inducing autophagy and subsequently modulating the Hippo/YAP pathway.

Steatosis regression assessed by cap after Vitamin 'D' supplementation in NAFLD patients with Vitamin 'D' deficiency

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease, and previous studies suggested a relationship between vitamin D deficiency and NAFLD. It is suggested that vitamin D supplementation may have significant beneficial effect on liver biochemistry and histology.

OBJECTIVE

This study aims to assess the degree of possible steatosis regression using controlled attenuation parameter (CAP) in NAFLD patients with vitamin D deficiency after vitamin D supplementation and evaluating its effect on lipid profile and transaminases.

PATIENTS AND METHODS

This study was conducted on 100 NAFLD patients with vitamin D deficiency. They received 10000 IU/week of vitamin D orally for 3 months. CAP was used to assess hepatic steatosis and fibrosis before/after intervention. Transaminases, lipid profile, and vitamin D levels were evaluated before/after treatment.

RESULTS

Serum AST, ALT, cholesterol, TG, LDL and HDL showed a significant reduction posttreatment in patients with both normal and elevated baseline levels ( P < 0.001). The posttreatment mean CAP showed a significant reduction (300.44 ± 37.56 vs. 265 ± 36.19 dB/ml) ( P  < 0.001), and there was a significant improvement in the mean fibrosis values by LSM (5.32 ± 1.53 vs. 4.86 ± 1.28 KPa) ( P  = 0.001). After supplementation, serum vitamin D level was raised significantly in the majority of patients ( P  < 0.001); however, only 13% of them reached sufficient levels (>30 ng/ml), insufficient levels (20-29 ng/ml) was reached in 83% and 5% showed vitamin D deficiency (<20 ng/ml).

CONCLUSION

A significant improvement was detected in hepatic steatosis (by CAP); mean values of LSM, transaminases and lipid profile after three months of oral vitamin D supplementation.

Neuroimmunomodulation of adrenoblockers during liver cirrhosis: modulation of hepatic stellate cell activity

The sympathetic nervous system and the immune system are responsible for producing neurotransmitters and cytokines that interact by binding to receptors; due to this, there is communication between these systems. Liver immune cells and nerve fibres are systematically distributed in the liver, and the partial overlap of both patterns may favour interactions between certain elements. Dendritic cells are attached to fibroblasts, and nerve fibres are connected via the dendritic cell-fibroblast complex. Receptors for most neuroactive substances, such as catecholamines, have been discovered on dendritic cells. The sympathetic nervous system regulates hepatic fibrosis through sympathetic fibres and adrenaline from the adrenal glands through the blood. When there is liver damage, the sympathetic nervous system is activated locally and systemically through proinflammatory cytokines that induce the production of epinephrine and norepinephrine. These neurotransmitters bind to cells through α-adrenergic receptors, triggering a cellular response that secretes inflammatory factors that stimulate and activate hepatic stellate cells. Hepatic stellate cells are key in the fibrotic process. They initiate the overproduction of extracellular matrix components in an active state that progresses from fibrosis to liver cirrhosis. It has also been shown that they can be directly activated by norepinephrine. Alpha and beta adrenoblockers, such as carvedilol, prazosin, and doxazosin, have recently been used to reverse CCl₄-induced liver cirrhosis in rodent and murine models.KEY MESSAGESNeurotransmitters from the sympathetic nervous system activate and increase the proliferation of hepatic stellate cells.Hepatic fibrosis and cirrhosis treatment might depend on neurotransmitter and hepatic nervous system regulation.Strategies to reduce hepatic stellate cell activation and fibrosis are based on experimentation with α-adrenoblockers.

Hematological Abnormalities in Cirrhosis: A Narrative Review

Liver cirrhosis remains a major public health issue. Liver fibrosis leading to cirrhosis is the terminal stage of various chronic liver diseases. Inflammatory cytokines are involved in the pathogenesis. Patients with cirrhosis often have hematological abnormalities, such as anemia and thrombocytopenia, which have multifactorial etiologies. Anemia in cirrhosis could be related to bleeding leading to iron deficiency anemia or other nutritional anemia such as vitamin B12 and folate deficiency. The pathophysiology of thrombocytopenia in liver cirrhosis has been postulated to range from splenic sequestration to bone marrow suppression from toxic agents, such as alcohol. It often complicates management due to the risk of bleeding with severely low platelets. This review aimed to highlight pathogenesis of liver cirrhosis, hematological abnormalities in liver cirrhosis, and their clinical significance.

Low 25 (OH) vitamin D levels are associated with increased prevalence of nonalcoholic fatty liver disease and significant liver fibrosis

AIMS

Evidence on the role of 25-Hydroxyvitamin D (25(OH)D) in the occurrence and progression of nonalcoholic fatty liver disease (NAFLD) is conflicting and population-based data are scarce. Here, we assess the association between 25(OH)D levels, NAFLD and liver fibrosis in the general population.

MATERIALS AND METHODS

This is an analysis of data from the 2017-2018 cycle of the National Health and Nutrition Examination Survey. We included adult participants with available data on vibration-controlled transient elastography (VCTE) and without viral hepatitis and significant alcohol consumption. Steatosis and fibrosis were diagnosed by the median values of controlled attenuation parameter (CAP) and liver stiffness measurement (LSM), respectively. 25(OH)D was measured by high performance liquid chromatography-tandem mass spectrometry.

RESULTS

A total of 3970 participants (1928 men and 2042 women) were included in the study. The prevalence of NAFLD (CAP ≥ 274 dB/m) and significant liver fibrosis (LSM ≥ 8 kPa) were 41.7% (95% CI 39.4-44.0) and 8.4% (95% CI 7.0-9.9), respectively, while 21.1% (95% CI 17.3-25.4) of participants had low 25(OH)D levels (<50 nmol/L). A multivariable logistic regression model adjusted for age, sex, race-ethnicity, body mass index, waist circumference, calendar period, diabetes, chronic kidney disease, and vitamin D supplementation showed that compared with participants with low 25(OH)D, those with optimal levels (≥75 nmol/L) had lower odds of both NAFLD (OR 0.73, 95% CI 0.55-0.98 p = 0.038) and significant liver fibrosis (OR 0.65, 95% CI 0.44-0.96, p = 0.033).

CONCLUSIONS

An inverse relationship was found between 25(OH)D and NAFLD and fibrosis, suggesting a possible role of vitamin D in NAFLD occurrence and progression.

Metabolic Injury of Hepatocytes Promotes Progression of NAFLD and AALD

Nonalcoholic liver disease is a component of metabolic syndrome associated with obesity, insulin resistance, and hyperlipidemia. Excessive alcohol consumption may accelerate the progression of steatosis, steatohepatitis, and fibrosis. While simple steatosis is considered a benign condition, nonalcoholic steatohepatitis with inflammation and fibrosis may progress to cirrhosis, liver failure, and hepatocellular cancer. Studies in rodent experimental models and primary cell cultures have demonstrated several common cellular and molecular mechanisms in the pathogenesis and regression of liver fibrosis. Chronic injury and death of hepatocytes cause the recruitment of myeloid cells, secretion of inflammatory and fibrogenic cytokines, and activation of myofibroblasts, resulting in liver fibrosis. In this review, we discuss the role of metabolically injured hepatocytes in the pathogenesis of nonalcoholic steatohepatitis and alcohol-associated liver disease. Specifically, the role of chemokine production and de novo lipogenesis in the development of steatotic hepatocytes and the pathways of steatosis regulation are discussed.

Multi-omics analyses of early liver injury reveals cell-type-specific transcriptional and epigenomic shift

Background

Liver fibrosis is a wound-healing response to tissue injury and inflammation hallmarked by the extracellular matrix (ECM) protein deposition in the liver parenchyma and tissue remodelling. Different cell types of the liver are known to play distinct roles in liver injury response. Hepatocytes and liver endothelial cells receive molecular signals indicating tissue injury and activate hepatic stellate cells which produce ECM proteins upon their activation. Despite the growing knowledge on the molecular mechanism underlying hepatic fibrosis in general, the cell-type-specific gene regulatory network associated with the initial response to hepatotoxic injury is still poorly characterized.

Results

In this study, we used thioacetamide (TAA) to induce hepatic injury in adult zebrafish. We isolated three major liver cell types - hepatocytes, endothelial cells and hepatic stellate cells - and identified cell-type-specific chromatin accessibility and transcriptional changes in an early stage of liver injury. We found that TAA induced transcriptional shifts in all three cell types hallmarked by significant alterations in the expression of genes related to fatty acid and carbohydrate metabolism, as well as immune response-associated and vascular-specific genes. Interestingly, liver endothelial cells exhibit the most pronounced response to liver injury at the transcriptome and chromatin level, hallmarked by the loss of their angiogenic phenotype.

Conclusion

Our results uncovered cell-type-specific transcriptome and epigenome responses to early stage liver injury, which provide valuable insights into understanding the molecular mechanism implicated in the early response of the liver to pro-fibrotic signals.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-08173-1.

Vitamin D deficiency in patients with chronic hepatitis D viral infection

Aim of the study

Vitamin D deficiency is known to be associated with disease severity, unresponsiveness to treatment, and morbidity among patients with chronic viral hepatitis B and C, autoimmune hepatitis, and alcoholic hepatitis. This study aims to research vitamin D levels in patients suffering from cirrhotic and non-cirrhotic phases of hepatitis D.

Material and methods

170 individuals in total were included in the study in the form of two groups: the first group of 100 patients with chronic hepatitis D (CHD), 30 of whom had cirrhosis, and the second control group of 70 individuals with similar characteristics to those of the first group in terms of age, type, and seasonal sampling. Levels of 25-hydroxy vitamin D [25(OH)D] were measured in the serum collected from patients and the control group.

Results

The lowest 25(OH)D levels were identified in patients with cirrhotic CHD. When these levels were compared with those of the control group, they were found to be significant (15.30 ±6.92 and 18.90 ±8.30 ng/ml, respectively, p = 0.04). 25(OH)D deficiency (< 10 ng/ml) was detected at significantly higher rates in patients with both cirrhotic and non-cirrhotic CHD compared to the healthy controls (30%, 25%, and 8.5%, respectively, p = 0.01). A significant correlation was established between 25(OH)D levels and bilirubin in patients with CHD (r = 0.252, p = 0.012). Multivariate analysis showed that chronic hepatitis D (odds ratio [OR] = 3.608, 95% confidence interval [CI]: 1.31-9.89, p = 0.013) and age (OR = 1.04, 95% CI: 1.00-1.08, p = 0.033) were associated with vitamin D deficiency.

Conclusions

Frequency of 25(OH)D vitamin deficiency is higher in patients with CHD. The identification of vitamin D levels and the replacement of any deficiency may create a positive effect on disease progression, morbidity, and mortality levels.

Differential effects of olive oil, soybean oil, corn oil and lard oil on carbon tetrachloride-induced liver fibrosis in mice

Olive oil could attenuate carbon tetrachloride (CCl₄) induced liver fibrosis (LF) in mouse model. The present study aimed to evaluate the effects of other common oils on CCl₄ induced LF. Healthy male ICR mice were administered with CCl₄ intraperitoneally at 2.5 ml/kg twice a week for total 3 weeks. Mice were pre-treated with olive oil, soybean oil, corn oil or lard oil. After treatment, histopathological changes were observed using Masson trichrome staining, and alanine aminotransferase (ALT), aspartate aminotransferase (AST), malondialdehyde (MDA), hydroxyproline (HYP) and triglyceride (TG) were measured by commercial kits. The expression of LF related genes was detected by quantitative real-time PCR. We found that soybean oil or olive oil significantly reduced ALT and AST levels in serum, and MDA, HYP and TG levels in the liver, compared with corn oil or lard oil. Moreover, Masson trichrome staining and real-time PCR showed that the mice treated with CCl₄ dissolved in soybean oil or olive oil had less fibrosis and apoptosis in the liver comparted to the mice treated with CCl₄ dissolved in corn oil or lard oil. In conclusion, soybean oil but not corn or lard oil exerts protective effects against CCl₄ induced LF in mice, possibly due to its antioxidant activity.

Prophylactical Low Dose Whole-Liver Irradiation Inhibited Colorectal Liver Metastasis by Regulating Hepatic Niche in Mice

Background

The liver is the most common target for metastatic colorectal cancer. Changes of the local hepatic niche due to hepatic diseases such as cirrhosis decrease the incidence of colorectal cancer liver metastasis. Hepatic niche heterogeneity could influence the risk of hepatic metastasis.

Materials and Methods

We simulated changes of the hepatic niche via prophylactical liver irradiation with a safe dose of 6 Gy. GEO dataset and GO analysis revealed a difference in the expression of matrix metalloproteinase 1 (MMP1) in primary colorectal cancer versus liver metastasis, as well as synchronous versus metachronous liver metastasis. Western blotting, Immunofluorescence and qRT-PCR were conducted to measure protein expressions, location and RNA expressions. Colony formation, wound-healing, transwell assays experiments were performed to determine the malignant biological properties of colorectal cancer cells. shRNA transfection was used to conduct stable transfected cell lines.

Results

Tissue inhibitor of metalloproteinases 1 (TIMP1) expression was significantly higher in metastases lesions than primary tumors. In vivo, TIMP1 expression in the hepatic niche increased after a safe dose of 6 Gy irradiation, along with MMP1 decreased, leading to collagen fiber deposition and impairment of hepatic microcirculation. In vitro, irradiated hepatic stellate cells-conditioned media reduced the migration and clone formation ability of colon cancer cells SW480 and HCT116. Low TIMP1 expression in hepatic stellate cells reduced tumor cell invasion and migration.

Conclusion

Prophylactical 6 Gy whole-liver irradiation could inhibit colorectal cancer liver metastasis by regulating TIMP1/MMP1 balance in the hepatic niche before liver metastatic lesion formed.

High dose vitamin D supplementation is associated with an improvement in serum markers of liver function

Limited studies have examined the effects of vitamin D on liver enzymes in patients with liver disease but none has explored its effects in the healthy subjects. The aim of present study was to evaluate the effects of a high dose vitamin D supplementation on measures of liver function. A total of 988 adolescent girls were recruited; all were assessed for liver function tests (LFTs) including alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), gamma-glutamyl transferase (ϒGT), alkaline phosphatase (ALP), total bilirubin, direct bilirubin, albumin, and total protein before and after supplementation with 50,000 IU cholecalciferol perls. Significant reductions were observed for AST, ALT, direct bilirubin, total bilirubin, LDH, and ϒGT at the end of supplementation, only in the group with abnormal reference value. Serum levels of total protein and albumin were higher at the end of follow up in the group with abnormal value. No significant change was obtained for LFTs in the group with normal value. Our findings suggest that vitamin D supplementation may improve markers of liver function in adolescents with abnormal LFTs. More randomized controlled trial with longer follow-up time will be required. © 2019 BioFactors, 45(3):335-342, 2019.

Protective role of arnebin-1 in rats with nonalcoholic fatty liver disease

Objective

To examine the effects of arnebin-1 on nonalcoholic fatty liver disease (NAFLD) induced by a high-fat diet (HFD).

Methods

Male Sprague–Dawley rats were fed an HFD for 10 weeks and then treated with arnebin-1 at a dose of 5, 10 or 20 mg/kg/day by gavage for a further 12 weeks of a 22-week HFD. Peripheral blood and liver tissues were collected for biochemical and histopathological examination. The mechanisms of arnebin-1 on liver fibrosis and insulin resistance (IR) were determined by Western blotting and real-time quantitative polymerase chain reaction.

Results

Arnebin-1 treatment attenuated the increase of total cholesterol, triglycerides, low-density lipoprotein cholesterol, aspartate aminotransferase and alanine aminotransferase in serum and lipid accumulation in the livers of HFD-fed rats. Furthermore, arnebin-1 abrogated HFD-induced liver fibrosis and the increase of fibrotic biomarkers. The HFD-induced decrease of hepatic proliferator-activated receptor γ and pro-matrix-metalloproteinase (MMP)-9 levels and the increase of tissue inhibitor of metalloproteinase-1 (TIMP-1) levels were reversed after arnebin-1. Arnebin-1 attenuated IR through activating the insulin receptor substrate-1/Akt/mTOR signalling pathway.

Conclusion

This study demonstrated that arnebin-1 ameliorates NAFLD, in part, by attenuating hepatic fibrosis and IR, suggesting that arnebin-1 may be a therapeutic agent for NAFLD treatment.

Serum Transaminase Concentrations and the Presence of Irritable Bowel Syndrome Are Associated with Serum 25-Hydroxy Vitamin D Concentrations in Adolescent Girls Who Are Overweight and Obese

Background/Aims: Vitamin D deficiency has become endemic globally and its etiology is complex. Few studies have investigated the determinants of serum 25-hydroxy vitamin D (25-OH D). The aim of this study was to investigate the association between lifestyle patterns, liver functional tests (LFTs), and the presence of irritable bowel syndrome (IBS) with serum 25-OH D in apparently healthy girls. Methods: This cross-sectional study was undertaken in 965 adolescent girls aged 12–18 years. IBS was diagnosed using the Rome III questionnaire. An electrochemiluminescence method was used to measure serum 25-OH D. LFTs were measured using commercial kits and an auto analyzer. Linear regression and univariate analyses were performed to determine the association between continuous and categorical variables with serum 25-OH D respectively. Results: Serum 25-OH D was significantly higher in normal weight subjects compared to either overweight or obese subjects (9.5 ± 7.02 vs. 7.9 ± 5.7 ng/mL, p = 0.03). Physical activity level was positively associated with serum 25-OH D in overweight and obese subjects (β = 0.15, p < 0.05). An inverse relationship was found between the presence of IBS and 25-OH D in both normal (β = –1.95, p < 0.05), overweight and obese subjects (β = –1.83, p < 0.05). Serum alanine transaminase (ALT; β = –0.19, p < 0.05) and aspartate transaminase (β = –0.17, p < 0.05) were inversely associated with serum 25-OH in overweight and obese subjects. Conclusions: Individuals with IBS had significantly lower serum 25-OH D concentrations. In addition, there was an inverse association between serum ALT and 25-OH D. Prospective studies, and perhaps interventional trials, will be required to clarify these associations.

Senescent hepatocyte secretion of matrix metalloproteinases is regulated by nuclear factor-κB signaling

AIMS

Cellular senescence and matrix metalloproteinases (MMPs) play an important role in liver diseases. The source and regulating factors of MMPs in senescent hepatocytes are not known. We investigated whether senescent hepatocytes secreted MMPs and if this was regulated by nuclear factor (NF)-κB.

MATERIALS AND METHODS

The TGF-α transgenic mouse hepatocyte line AML12 was treated with H₂O₂ to induce senescence. NF-κB signaling was examined by Western blotting and luciferase reporter assays. Quantitative reverse transcription polymerase chain reaction was used to evaluated expression of MMP-2, -9 and -13.

KEY FINDINGS

AML12 cells treated with H₂O₂ showed the characteristic morphology of senescence. The activity of NF-κB and expression of MMP-2, -9 and -13 were increased in senescent AML12 cells. The NF-κB inhibitor BAY 11-7082 decreased the levels of MMPs.

SIGNIFICANCE

These results suggest that senescent hepatocytes are involved in the pathology of liver diseases through remodeling the extracellular matrix.

Adenoviral‑bone morphogenetic protein‑7 and/or doxazosin therapies promote the reversion of fibrosis/cirrhosis in a cirrhotic hamster model

Liver fibrosis occurs in the presence of continuous insults, including toxic or biological agents. Novel treatments must focus on ceasing the progression of cellular damage, promoting the regeneration of the parenchyma and inhibition of the fibrotic process. The present study analyzed the effect of bone morphogenetic protein (BMP)-7 gene therapy with or without co-treatment with doxazosin in a model of liver cirrhosis in hamsters. The serum alanine aminotransferase, aspartate aminotransferase and albumin levels were analyzed spectrophotometrically. Tissue hepatic samples were analyzed by hematoxylin and eosin for parenchymal structure and Sirius red for collagen fiber content. BMP-7 and α-smooth muscle actin (SMA)-positive cells were detected by immunohistochemistry. BMP-7 and collagen type I content in hepatic tissue were analyzed by western blotting, and tissue inhibitor of metalloproteinases (TIMP)-2 and matrix metalloproteinase (MMP)-13 expression levels were detected by reverse transcription-quantitative polymerase chain reaction. The present study detected a significant reduction of collagen type I deposits in the group treated with adenoviral-transduction with BMP-7 and doxazosin. In animals with BMP-7 and doxazosin therapy, α-SMA-positive cells were 31.7 and 29% significantly decreased compared with animals with placebo, respectively. Adenoviral-BMP-7 transduction and/or doxazosin treatments actively induced decrement in type I collagen deposition via increased MMP-13 and reduced TIMP-2 expression. In conclusion, the adenovirus-BMP-7 gene therapy and the doxazosin therapy are potential candidates for the diminution of fibrosis in the liver, although combination of both therapies does not improve the individual anti-fibrotic effect once cirrhosis is established.

The neglected avian hepatotropic virus induces acute and chronic hepatitis in ducks: an alternative model for hepatology

Duck Hepatitis A Virus (DHAV) belongs to the Avihepatovirus, which is also classified into Picornaviridae with Hepatovirus, Hepatitis A Virus (HAV). In humans, the pathogenesis of HAV is not well understood because of limited work with animal models. Here, we investigated the progress of duck viral hepatitis caused by DHAV and their potential for dissecting the pathogenesis of HAV. During the course of infection, the duck model had undergone hepatocellular lesions (vacuolation, acidophilic degeneration and steatosis), lymphocytes recruitment (neutrophil granulocytes, heterophilic granulocytes and T cells or plasm cells) and repair (activation of hepatic stellate cells, fibrosis and regeneration). Coincident with liver injury, the serum biomarkers, aspartate aminotransferase and alanine transaminase were significantly increased. Moreover, comparatively lower CD4+ and CD8+ T-cells were recruited to the liver, which might lead to a persistent infection (40 wk). Because DHAV and HAV have similar genomic structure, biological phenotypes and can easily replicate in liver. And half of fibrosis-related genes had high homology between humans and ducks. Considering these similarity in pathological and virological phenotypes, we proposed that the ducks might be an alternatively small animal model that would provide insight into the pathogenesis of viral hepatitis, fibrosis and liver regeneration.

Hepatic SATB1 induces paracrine activation of hepatic stellate cells and is upregulated by HBx

Chronic hepatitis B virus (HBV) infection is a major cause of chronic liver diseases, but its involvement in hepatic fibrogenesis remains unclear. Special AT-rich binding protein 1 (SATB1) has been implicated in reprogramming chromatin organization and transcription profiles in many cancers and non-cancer-related conditions. We found that hepatic SATB1 expression was significantly up-regulated in fibrotic tissues from chronic hepatitis B virus (HBV)-infected patients and HBV transgenic (HBV-Tg) mouse model. Knockdown of SATB1 in the liver significantly alleviated CCl4-induced fibrosis in HBV-Tg mouse model. Moreover, we suggested HBV encoded x protein (HBx) induced SATB1 expression through activation of JNK and ERK pathways. Enforced expression of SATB1 in hepatocytes promoted the activation and proliferation of hepatic stellate cells (HSCs) by secretion of connective tissue growth factor (CTGF), Interleukin-6 (IL-6) and platelet derived growth factor-A (PDGF-AA). Our findings demonstrated that HBx upregulated hepatic SATB1 which exerted pro-fibrotic effects by paracrine activation of stellate cells in HBV-related fibrosis.

Hepatocytes in liver injury: Victim, bystander, or accomplice in progressive fibrosis?

Chronic liver disease causes significant morbidity and mortality through progressive fibrosis, cirrhosis, and liver cancer. The classical theory of fibrogenesis has hepatic stellate cells (HSCs) as the principal and only significant source of abnormal extracellular matrix (ECM). Further, HSCs have the major role in abnormal ECM turnover. It is the death of hepatocytes, as the initial target of injury, that initiates a sequence of events including the recruitment of inflammatory cells and activation of HSCs. Following this initial response, the ongoing insult to hepatocytes is regarded as perpetuating injury, but otherwise, hepatocytes are regarded as "victims" and "bystanders" in progressive fibrosis. Recent developments, however, challenge this view and suggest the concept of the hepatocyte being an active participant in liver injury. It is clear now that hepatocytes undergo phenotypic changes, adapt to injury, and react to the altered microenvironment. In this review, we describe studies showing that hepatocytes contribute to progressive fibrosis by direct manipulation of the surrounding ECM and through signaling to effector cells, particularly HSCs and intrahepatic immune cells. Together, these findings suggest an active "accomplice" role for the hepatocyte in progressive liver fibrosis and highlight novel pathways that could be targeted for development of future anti-fibrotic therapies.

Prediagnostic circulating vitamin D levels and risk of hepatocellular carcinoma in European populations: a nested case-control study

The association between vitamin D status and hepatocellular carcinoma (HCC) has not been well investigated, despite experimental evidence supporting an important role of vitamin D in liver pathophysiology. Our objective was to investigate the association between prediagnostic circulating 25-hydroxyvitamin D [25(OH)D] serum levels and the risk of HCC in a prospective, nested case-control study among 520,000 participants in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Each case (n = 138) diagnosed between 1992 and 2010 was matched to one control by age, sex, study center, date and time of blood collection, and fasting status. Serum baseline levels of 25(OH)D were measured by liquid chromatography/tandem mass spectrometry. Multivariable incident rate ratios (IRRs) of HCC associated with continuous (per 10 nmol/L) or categorical levels (tertiles or a priori-defined categories) of prediagnostic 25(OH)D were calculated using conditional logistic regression. Higher 25(OH)D levels were associated with a 49% reduction in the risk of HCC (highest versus lowest tertile: multivariable IRR = 0.51, 95% confidence interval [CI], 0.26 to 0.99; Ptrend  = 0.04; per 10 nmol/L increase: IRR = 0.80, 95% CI, 0.68-0.94). The finding did not vary substantially by time from enrolment to diagnosis, and did not change after adjustment for biomarkers of preexisting liver damage, nor chronic infection with hepatitis B or C viruses. The findings were not modified by body size or smoking status.

CONCLUSION

In this prospective study on western European populations, serum levels of 25(OH)D were inversely associated with the risk of HCC. Given the rising incidence of this cancer in low-risk developed countries and the strong public health interest surrounding the potentially cancer-protective roles of vitamin D, additional studies in different populations are required.

The association of vitamin D deficiency with non-alcoholic fatty liver disease

OBJECTIVE

Vitamin D deficiency has been related to diabetes, hypertension, hyperlipidemia and peripheral vascular disease. In this study, we aimed to investigate the role of vitamin D status in non-alcoholic fatty liver disease.

METHODS

We included 211 consecutive subjects to examine the presence of non-alcoholic fatty liver disease. Of these subjects, 57 did not have non-alcoholic fatty liver disease and 154 had non-alcoholic fatty liver disease.

RESULTS

The non-alcoholic fatty liver disease group had significantly higher fasting blood glucose (p = 0.005), uric acid (p = 0.001), aspartate aminotransferase (p<0.001), alanine aminotransferase (p<0.001), γ-glutamyltransferase (p<0.0001), alkaline phosphatase (p = 0.028), HbA1c (p<0.001), ferritin (p<0.001), insulin (p = 0.016), C-peptide (p = 0.001), HOMA-IR (p = 0.003), total cholesterol (p = 0.001), triglyceride (p = 0.001) and white blood cell (p = 0.04) levels. In contrast, the non-alcoholic fatty liver disease group had significantly lower 25(OH)D levels (12.3±8.9 ng/dl, p<0.001) compared with those of the control group (20±13.6 ng/dl).

CONCLUSIONS

In this study, we found lower serum 25(OH)D levels in patients with non-alcoholic fatty liver disease than in subjects without non-alcoholic fatty liver disease. To establish causality between vitamin D and non-alcoholic fatty liver disease, further interventional studies with a long-term follow-up are needed.

Hepatocyte produced matrix metalloproteinases are regulated by CD147 in liver fibrogenesis

BACKGROUND

The classical paradigm of liver injury asserts that hepatic stellate cells (HSC) produce, remodel and turnover the abnormal extracellular matrix (ECM) of fibrosis via matrix metalloproteinases (MMPs). In extrahepatic tissues MMP production is regulated by a number of mechanisms including expression of the glycoprotein CD147. Previously, we have shown that CD147 is expressed on hepatocytes but not within the fibrotic septa in cirrhosis [1]. Therefore, we investigated if hepatocytes produce MMPs, regulated by CD147, which are capable of remodelling fibrotic ECM independent of the HSC.

METHODS

Non-diseased, fibrotic and cirrhotic livers were examined for MMP activity and markers of fibrosis in humans and mice. CD147 expression and MMP activity were co-localised by in-situ zymography. The role of CD147 was studied in-vitro with siRNA to CD147 in hepatocytes and in-vivo in mice with CCl4 induced liver injury using ãCD147 antibody intervention.

RESULTS

In liver fibrosis in both human and mouse tissue MMP expression and activity (MMP-2, -9, -13 and -14) increased with progressive injury and localised to hepatocytes. Additionally, as expected, MMPs were abundantly expressed by activated HSC. Further, with progressive fibrosis there was expression of CD147, which localised to hepatocytes but not to HSC. Functionally significant in-vitro regulation of hepatocyte MMP production by CD147 was demonstrated using siRNA to CD147 that decreased hepatocyte MMP-2 and -9 expression/activity. Further, in-vivo α-CD147 antibody intervention decreased liver MMP-2, -9, -13, -14, TGF-β and α-SMA expression in CCl4 treated mice compared to controls.

CONCLUSION

We have shown that hepatocytes produce active MMPs and that the glycoprotein CD147 regulates hepatocyte MMP expression. Targeting CD147 regulates hepatocyte MMP production both in-vitro and in-vivo, with the net result being reduced fibrotic matrix turnover in-vivo. Therefore, CD147 regulation of hepatocyte MMP is a novel pathway that could be targeted by future anti-fibrogenic agents.

Pathogenesis of liver cirrhosis

Liver cirrhosis is the final pathological result of various chronic liver diseases, and fibrosis is the precursor of cirrhosis. Many types of cells, cytokines and miRNAs are involved in the initiation and progression of liver fibrosis and cirrhosis. Activation of hepatic stellate cells (HSCs) is a pivotal event in fibrosis. Defenestration and capillarization of liver sinusoidal endothelial cells are major contributing factors to hepatic dysfunction in liver cirrhosis. Activated Kupffer cells destroy hepatocytes and stimulate the activation of HSCs. Repeated cycles of apoptosis and regeneration of hepatocytes contribute to pathogenesis of cirrhosis. At the molecular level, many cytokines are involved in mediation of signaling pathways that regulate activation of HSCs and fibrogenesis. Recently, miRNAs as a post-transcriptional regulator have been found to play a key role in fibrosis and cirrhosis. Robust animal models of liver fibrosis and cirrhosis, as well as the recently identified critical cellular and molecular factors involved in the development of liver fibrosis and cirrhosis will facilitate the development of more effective therapeutic approaches for these conditions.

Rat model of fractionated (2 Gy/day) 60 Gy irradiation of the liver: long-term effects

The liver is considered a radiosensitive organ. However, in rats, high single-dose irradiation (HDI) showed only mild effects. Consequences of fractionated irradiation (FI) in such an animal model have not been studied so far. Rats were exposed to selective liver FI (total dose 60 Gy, 2 Gy/day) or HDI (25 Gy) and were killed three months after the end of irradiation. To study acute effects, HDI-treated rats were additionally killed at several time points between 1 and 48 h. Three months after irradiation, no differences between FI and HDI treatment were found for macroscopically detectable small "scars" on the liver surface and for an increased number of neutrophil granulocytes distributed in the portal fields and through the liver parenchyma. As well, no changes in HE-stained tissues or clear signs of fibrosis were found around the portal vessels. Differences were seen for the number of bile ducts being increased in FI- but not in HDI-treated livers. Serum levels indicative of liver damage were determined for alkaline phosphatase (AP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (γGT) and lactate dehydrogenase (LDH). A significant increase of AP was detected only after FI while HDI led to the significant increases of AST and LDH serum levels. By performing RT-PCR, we detected up-regulation of matrix metalloproteinases, MMP-2, MMP-9, MMP-14, and of their inhibitors, TIMP-1, TIMP-2 and TIMP-3, shortly after HDI, but not at 3 month after FI or HDI. Overall, we saw punctual differences after FI and HDI, and a diffuse formation of small scars at the liver surface. Lack of "provisional clot"-formation and absence of recruitment of mononuclear phagocytes could be one explanation for scar formation as incomplete repair response to irradiation.

Bone marrow mononuclear cell transplantation increases metalloproteinase-9 and 13 and decreases tissue inhibitors of metalloproteinase-1 and 2 expression in the liver of cholestatic rats

Liver fibrosis results from chronic injury followed by activation of macrophages and fibrogenic cells like myofibroblasts and activated hepatic stellate cells. These fibrogenic cells express α-smooth muscle actin (α-SMA) and produce excessive extracellular matrix (ECM), with disorganization and loss of function of hepatic parenchyma. It is known that increased levels of metalloproteinases (MMPs) in liver fibrosis are associated with reduction of the pathologic ECM and fibrosis resolution. Recently, it has been shown that bone marrow mononuclear cells (BMMNCs) may reduce collagen and α-SMA expression, and ameliorate liver function in cholestatic rats. Therefore, this study aimed to analyze MMP-2, MMP-9 and MMP-13, and tissue inhibitors of MMPs (TIMPs)-1 and TIMP-2 in the liver of cholestatic rats transplanted with BMMNC. Animals were divided into normal rats, cholestatic rats obtained after 14 and 21 days of bile duct ligation (BDL), and rats obtained after 14 days of BDL that received BMMNCs and were killed after 7 days. MMP and TIMP expression was assessed by Western blotting, along with α-SMA, CD68 and CD11b expression by confocal microscopy. Western blotting analysis showed that 14-day BDL animals had significantly reduced amounts of MMP-2 and MMP-13, but increased amounts of MMP-9 compared to normal rats. After 21 days of BDL, overall MMP amounts were decreased and TIMPs were increased. BMMNC transplantation significantly increased MMP-9 and MMP-13, and decreased TIMP expression. Increased MMP activity was confirmed by zymography. MMP-9 and MMP-13 were expressed by macrophages near fibrotic septa, suggesting BMMNC may stimulate MMP production in fibrotic livers, contributing to ECM degradation and hepatic regeneration.

Independent associations of low 25 hydroxy vitamin D and high parathyroid hormonal levels with nonalcoholic fatty liver disease in Asian Indians residing in north India

OBJECTIVE

We analysed the associations of 25 hydroxy vitamin D [25(OH) D] and parathyroid hormone (PTH) levels with clinical, anthropometric, biochemical and body composition parameters in Asian Indians with nonalcoholic fatty liver disease (NAFLD).

METHODS

In this case-control study, 162 cases and 173 age and sex matched controls were recruited. Clinical, anthropometric, biochemical parameters and liver ultrasound were done. Percentage body fat (%BF), lean body mass and bone mineral density (BMD) were assessed by dual energy X-ray absorptiometry (DXA). Fasting insulin levels, value of homeostasis model assessment of insulin resistance (HOMA-IR), serum 25(OH) D, calcium and PTH levels were measured.

RESULTS

Subjects with NAFLD had lower serum 25(OH) D (19.4 ± 8.5 vs. 27.8 ± 9.4 ng/ml, p = 0.0001) and higher serum PTH (54.9 ± 19.5 vs.41.5 ± 18.3 pg/ml, p = 0.0001) levels as compared to controls. We observed significantly high values of systolic blood pressure (p = 0.002), waist circumference (p = 0.05), serum triglycerides (p = 0.002), total cholesterol (p = 0.002), alanine transaminase (p = 0.05), fasting insulin (p = 0.02) and HOMA-IR (p = 0.03) in the lowest 25(OH) D quartile. Multivariable-logistic regression showed that low serum 25(OH) D [OR (95%CI): 4.46 (2.58-7.72), p = 0.0001] and high PTH [OR (95%CI): 2.21 (1.50-3.30), p = 0.0001] level were independently associated with NAFLD.

CONCLUSION

Low serum 25(OH) D and high PTH levels were independently associated with the presence of NAFLD in Asian Indians residing in north India.

Gene network profiling before and after transplantation in alcoholic cirrhosis liver transplant recipients

The main objective of this study was to define a gene network profile network in liver transplant recipients with alcoholic cirrhosis before and after liver transplantation. Genes were selected from data obtained in a previous study of liver transplant recipients with alcoholic cirrhosis. Selected up-regulated genes were further validated by quantitative real-time polymerase chain reaction in different groups of liver transplant recipients with alcoholic cirrhosis (n=5). Selected genes up-regulated before transplantation were: TNFRSF9 (tumor necrosis factor [TNF] receptor superfamily, member 9); IL2RB (interleukin-2 receptor beta); BCL2L2 (BCL2-like 2); NOX5 (NADPH) oxidase, EF-hand calcium binding domain 5); PEX5 (peroxisomal biogenesis factor 5); PPARG (peroxisome proliferator-activated receptor gamma); NIBP (IKK2 binding protein); NKIRAS2 (NFKappaBeta inhibitor interacting Ras-like 2); IL4 (interleukin-4); IL-4R (interleukin 4 receptor); ADH1A (alcohol dehydrogenase 1A, class 1); ALDH1L1 (aldehyde dehydrogenase 1 family, member L1); MPO (myeloperoxidase); NPPA (natriuretic peptide precursor A); BCL2A1 (BCL2-related protein A1); GADD45A (growth arrest and DNA-damage-inducible alpha); TEGT (Bax inhibitor 1); PIK3CA (phosphoinositide-3-kinase, catalytic, alpha polypeptide); IFNGR2 (interferon gamma receptor 2); JAK2 (Janus Kinase 2); FAS (Fas, TNF receptor superfamily, member 6); TANK (TRAF family member-associated NFKB activator); TTRAP (TRAF and TNF receptor-associated protein); and ANXA5 (annexin A5).

Matrix metalloproteinase 3 is a mediator of pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) may be triggered by epithelial injury that results in aberrant production of growth factors, cytokines, and proteinases, leading to proliferation of myofibroblasts, excess deposition of collagen, and destruction of the lung architecture. The precise mechanisms and key signaling mediators responsible for this aberrant repair process remain unclear. We assessed the importance of matrix metalloproteinase-3 (MMP-3) in the pathogenesis of IPF through i) determination of MMP-3 expression in patients with IPF, ii) in vivo experiments examining the relevance of MMP-3 in experimental models of fibrosis, and iii) in vitro experiments to elucidate possible mechanisms of action. Gene expression analysis, quantitative RT-PCR, and Western blot analysis of explanted human lungs revealed enhanced expression of MMP-3 in IPF, compared with control. Transient adenoviral vector-mediated expression of recombinant MMP-3 in rat lung resulted in accumulation of myofibroblasts and pulmonary fibrosis. Conversely, MMP-3-null mice were protected against bleomycin-induced pulmonary fibrosis. In vitro treatment of cultured lung epithelial cells with purified MMP-3 resulted in activation of the β-catenin signaling pathway, via cleavage of E-cadherin, and induction of epithelial-mesenchymal transition. These processes were inhibited in bleomycin-treated MMP-3-null mice, as assessed by cytosolic translocation of β-catenin and cyclin D1 expression. These observations support a novel role for MMP-3 in the pathogenesis of IPF, through activation of β-catenin signaling and induction of epithelial-mesenchymal transition.

MMP-9 activity is increased by adiponectin in primary human hepatocytes but even negatively correlates with serum adiponectin in a rodent model of non-alcoholic steatohepatitis

Adiponectin protects from inflammation and fibrosis in metabolic liver disease. In the present study we analyzed whether this adipokine may directly affect the activity of matrix metalloproteinases (MMPs), central regulators of fibrinolysis, in hepatocytes. Global gene expression analysis indicated upregulation of MMP-9 and tissue inhibitor of metalloproteinases-1 (TIMP-1) expression in primary human hepatocytes (PHH) in response to stimulation with adiponectin, and these results were confirmed by real-time RT-PCR. Furthermore, gelatin zymography revealed that MMP-9 activity was significantly induced in supernatants of adiponectin stimulated PHHs. In a murine model of hepatic steatosis and in human steatotic liver samples hepatic MMP-9 activity was not significantly altered. However, in two different murine models of non-alcoholic steatohepatitis (NASH) MMP-9 activity was significantly elevated compared to chow fed control mice. Of note, MMP-9 activity did not or even negatively, respectively, correlate with adiponectin serum levels in these models. The current data indicate that in NASH hepatic inflammation and fibrosis but not hepatic steatosis induce liver MMP-9 activity, and this induction seems to be related to the anti-inflammatory activity of adiponectin rather than its effect on hepatocellular MMP-9 expression.

Strong association between non alcoholic fatty liver disease (NAFLD) and low 25(OH) vitamin D levels in an adult population with normal serum liver enzymes

BACKGROUND

Hypovitaminosis D has been recently recognized as a worldwide epidemic. Since vitamin D exerts significant metabolic activities, comprising free fatty acids (FFA) flux regulation from the periphery to the liver, its deficiency may promote fat deposition into the hepatocytes. Aim of our study was to test the hypothesis of a direct association between hypovitaminosis D and the presence of NAFLD in subjects with various degree of insulin-resistance and related metabolic disorders.

METHODS

We studied 262 consecutive subjects referred to the Diabetes and Metabolic Diseases clinics for metabolic evaluation. NAFLD (non-alcoholic fatty liver disease) was diagnosed by upper abdomen ultrasonography, metabolic syndrome was identified according to the Third Report of National Cholesterol Education Program/Adult Treatment Panel (NCEP/ATPIII) modified criteria. Insulin-resistance was evaluated by means of HOMA-IR. Fatty-Liver-Index, a recently identified correlate of NAFLD, was also estimated. Serum 25(OH)vitamin D was measured by colorimetric method.

RESULTS

Patients with NAFLD (n=162,61.8%) had reduced serum 25(OH) vitamin D levels compared to subjects without NAFLD (14.8±9.2 vs 20.5±9.7 ng/ml, p<0.001, OR 0.95, IC 95% 0.92-0.98). The relationship between NAFLD and reduced 25(OH)vitamin D levels was independent from age, sex, triglycerides, high density lipoproteins (HDL) and glycaemia (p<0.005) and Fatty Liver Index inversely correlated with low 25(OH) vitamin D regardless sex, age and HOMA-IR (p<0.007).

CONCLUSIONS

Low 25(OH)vitamin D levels are associated with the presence of NAFLD independently from metabolic syndrome, diabetes and insulin-resistance profile.

Loss of matrix metalloproteinase-2 amplifies murine toxin-induced liver fibrosis by upregulating collagen I expression

BACKGROUND AND AIMS

Matrix metalloproteinase-2 (MMP-2), a type IV collagenase secreted by activated hepatic stellate cells (HSCs), is upregulated in chronic liver disease and is considered a profibrotic mediator due to its proliferative effect on cultured HSCs and ability to degrade normal liver matrix. Although associative studies and cell culture findings suggest that MMP-2 promotes hepatic fibrogenesis, no in vivo model has definitively established a pathologic role for MMP-2 in the development and progression of liver fibrosis. We therefore examined the impact of MMP-2 deficiency on liver fibrosis development during chronic CCl(4) liver injury and explored the effect of MMP-2 deficiency and overexpression on collagen I expression.

METHODS

Following chronic CCl(4) administration, liver fibrosis was analyzed using Sirius Red staining with quantitative morphometry and real-time polymerase chain reaction (PCR) in MMP-2-/- mice and age-matched MMP-2+/+ controls. These studies were complemented by analyses of cultured human stellate cells.

RESULTS

MMP-2-/- mice demonstrated an almost twofold increase in fibrosis which was not secondary to significant differences in hepatocellular injury, HSC activation or type I collagenase activity; however, type I collagen messenger RNA (mRNA) expression was increased threefold in the MMP-2-/- group by real-time PCR. Furthermore, targeted reduction of MMP-2 in cultured HSCs using RNA interference significantly increased collagen I mRNA and protein, while overexpression of MMP-2 resulted in decreased collagen I mRNA.

CONCLUSIONS

These findings suggest that increased MMP-2 during the progression of liver fibrosis may be an important mechanism for inhibiting type I collagen synthesis by activated HSCs, thereby providing a protective rather than pathologic role.

Entamoeba histolytica calreticulin: an endoplasmic reticulum protein expressed by trophozoites into experimentally induced amoebic liver abscesses

Entamoeba histolytica calreticulin (EhCRT) is remarkably immunogenic in humans (90-100% of invasive amoebiasis patients). Nevertheless, the study of calreticulin in this protozoan is still in its early stages. The exact location, biological functions, and its role in pathogenesis are yet to be fully understood. The aim of the present work is to determine the location of EhCRT in virulent trophozoites in vivo and the expression of the Ehcrt gene during the development of experimentally induced amoebic liver abscesses (ALA) in hamsters. Antibodies against recombinant EhCRT were used for the immunolocalization of EhCRT in trophozoites through confocal microscopy; immunohistochemical assays were also performed on tissue sections of ALAs at different times after intrahepatic inoculation. The expression of the Ehcrt gene during the development of ALA was estimated through both in situ RT-PCR and real-time RT-PCR. Confocal assays of virulent trophozoites showed a distribution of EhCRT in the cytoplasmic vesicles of different sizes. Apparently, EhCRT is not exported into the hepatic tissue. Real-time RT-PCR demonstrated an over-expression of the Ehcrt gene at 30 min after trophozoite inoculation, reaching a peak at 1-2 h; thereafter, the expression fell sharply to its original levels. These results demonstrate for the first time in an in vivo model of ALA, the expression of Ehcrt gene in E. histolytica trophozoites and add evidence that support CRT as a resident protein of the ER in E. histolytica species. The in vivo experiments suggest that CRT may play an important role during the early stages of the host-parasite relationship, when the parasite is adapting to a new environment, although the protein seems to be constitutively synthesized. Moreover, trophozoites apparently do not export EhCRT into the hepatic tissue in ALA.

Prevalence of vitamin D deficiency in chronic liver disease

Vitamin D deficiency has been associated with cholestatic liver disease such as primary biliary cirrhosis. Some studies have suggested that cirrhosis can predispose patients to development of osteoporosis because of altered calcium and vitamin D homeostasis. The aim of this study was to determine the prevalence of vitamin D deficiency in patients with chronic liver disease.

METHODS

One hundred and eighteen consecutive patients (43 with hepatitis C cirrhosis, 57 with hepatitis C but no cirrhosis, 18 with nonhepatitis C-related cirrhosis) attending the University of Tennessee Hepatology Clinic had their 25-hydroxyvitamin D level measured. Severity of vitamin D deficiency was graded as mild (20-32 ng/ml), moderate (7-19 ng/ml) or severe (<7 ng/ml), normal being >32 ng/ml.

RESULTS

Of patients, 109/118 (92.4%) had some degree of vitamin D deficiency. In the hepatitis C cirrhosis group, 16.3% (7/43) had mild, 48.8% (21/43) had moderate, and 30.2% (13/43) had severe vitamin D deficiency. In the hepatitis C noncirrhotic group, 22.8% (19/57) had mild, 52.6% (30/57) had moderate, and 14% (8/57) had severe vitamin D deficiency. In the nonhepatitis C-related cirrhosis group, 38.9% (7/18) had mild, 27.8% (5/18) had moderate, and 27.8% (5/18) had severe vitamin D deficiency. Severe vitamin D deficiency (<7 ng/ml) was more common among patients with cirrhosis compared with noncirrhotics (29.5% versus 14.1%, P value=0.05). Female gender, African American race, and cirrhosis were independent predictors of severe vitamin D deficiency in chronic liver disease.

CONCLUSION

Vitamin D deficiency is universal (92%) among patients with chronic liver disease, and at least one-third of them suffer from severe vitamin D deficiency. African American females are at highest risk of vitamin D deficiency.

Antifibrotic activity of anisodamine in vivo is associated with changed intrahepatic levels of matrix metalloproteinase-2 and its inhibitor tissue inhibitors of metalloproteinases-2 and transforming growth factor beta1 in rats with carbon tetrachloride-induced liver injury

BACKGROUND AND AIM

To investigate the protective effects and the mechanism of anisodamine on deposition of extracellular matrix in experimental liver fibrosis.

METHODS

Experimental liver fibrosis was produced by carbon tetrachloride (CCL(4)). The preventive group was treated for 10 weeks with anisodamine 7.0 mg/kg per day i.p. injection. Two therapeutic groups were treated for 6 weeks by anisodamine 7.0 or 14.0 mg/kg per day i.p. injection. Studies were made at CCL(4) administration on the 10th weekend. Serum biochemical indices and the contents of malondialdehyde (MDA) and hydroxyproline (HYP) in livers were compared. The expression of transforming growth factor-beta1 (TGF-beta1) was observed by immunohistochemistry. The reverse transcription polymerase chain reaction was used to detect the expressions of matrix metalloproteinase-2 (MMP2) and tissue inhibitor of metalloproteinase-2 (TIMP2) mRNA in livers and the ratio of MMP2 and TIMP2 was measured. The proteins of MMP2 in liver were determined by gelatin zymography.

RESULTS

The serum levels of alanine aminotransferase, aspartate aminotransferase, gamma-glutamyltransferase and hyaluronic acid of liver fibrosis rats improved significantly by treatment with anisodamine. The contents of MDA and HYP in liver decreased and the expressions of TGF-beta1 were inhibited by treatment with anisodamine. The levels of MMP2 and TIMP2 mRNA and the protein of MMP2 in livers were significantly reduced in the anisodamine preventive group and therapeutic groups. The expression ratios of MMP2 and TIMP2 mRNA were adjusted in treated groups.

CONCLUSION

Anisodamine can inhibit hepatic fibrosis.

Vitamin D and parathyroid hormone in outpatients with noncholestatic chronic liver disease

BACKGROUND & AIMS

The liver plays a central role in vitamin D metabolism. Our aim was to determine the prevalence and type of vitamin D-parathyroid hormone (PTH) disturbance in ambulatory patients with noncholestatic chronic liver disease (CLD) and its relationship with disease severity and liver function.

METHODS

We studied 100 consecutive outpatients (63 men, 37 women; mean age, 49.0 +/- 12.1 [SD] y) with noncholestatic CLD caused by alcohol (n = 40), hepatitis C (n = 38), hepatitis B (n = 12), autoimmune hepatitis (n = 4), hemochromatosis (n = 4), and nonalcoholic steatohepatitis (n = 2); 51 patients had cirrhosis. Serum concentrations of 25-hydroxyvitamin D (25[OH]D), PTH, calcium, phosphate, magnesium, creatinine, and liver function tests were determined.

RESULTS

Serum 25(OH)D levels were inadequate in 91 patients: vitamin D deficiency (<50 nmol/L) was found in 68 patients and vitamin D insufficiency (50-80 nmol/L) was found in 23 patients. Secondary hyperparathyroidism (serum PTH, >6.8 pmol/L) was present in 16 patients. The prevalence of vitamin D deficiency was significantly higher in cirrhotic vs noncirrhotic patients (86.3% vs 49.0%; P = .0001). In Child-Pugh class C patients, 25(OH)D levels were significantly lower than in class A patients (22.7 +/- 10.0 nmol/L vs 45.8 +/- 16.8 nmol/L; P < .001). Serum 25(OH)D independently correlated with international normalized ratio (negatively; P = .018) and serum albumin (positively; P = .007). Serum 25(OH)D levels of less than 25 nmol/L predicted coagulopathy, hyperbilirubinemia, hypoalbuminemia, increased alkaline phosphatase, and anemia and thrombocytopenia.

CONCLUSIONS

Vitamin D inadequacy is common in noncholestatic CLD and correlates with disease severity, but secondary hyperparathyroidism is relatively infrequent. Management of CLD should include assessment of vitamin D status in all patients and replacement when necessary.

Loss of MMP 13 attenuates murine hepatic injury and fibrosis during cholestasis

Cholestasis occurs in a variety of clinical settings and often results in liver injury and secondary biliary fibrosis. Several matrix metalloproteinases (MMPs) are upregulated in the liver during cholestasis. The function of the major interstitial collagenase, MMP-13, in the initial phase of liver fibrosis is unknown. The aim of this study was to evaluate the role of MMP-13 during the development of cholestasis-induced liver fibrosis by comparing wild-type and MMP-13-deficient mice. Cholestasis was induced by bile duct ligation (BDL) for 5 days or 3 weeks. Activation and proliferation of hepatic stellate cells (HSCs) were detected by immunohistochemistry. Expression of MMP-13 mRNA increased significantly in BDL livers of WT mice. After BDL for 3 weeks liver fibrosis was suppressed in MMP-13-deficient mice versus WT animals. Activation and proliferation of HSCs were also suppressed in livers of MMP-13-deficient mice after BDL. To clarify the mechanism of this suppression, samples from 5-day BDL mice were used for evaluation of liver injury. Compared with those in WT animals, serum ALT and the number of hepatic neutrophils were reduced in MMP-13-deficient mice. Increased expression of the mRNA of inflammatory mediators such as tumor necrosis factor-alpha (TNF-alpha) was significantly suppressed in livers of MMP-13-deficient mice. Upregulation of fibrogenic markers, for example, transforming growth factor beta1 (TGF-beta1), was also significantly suppressed in livers of MMP-13-deficient mice versus in WT mice. In conclusion, distinct from the known function of interstitial collagenase to reduce liver fibrosis by degrading the extracellular matrix, MMP-13 contributes to accelerating fibrogenesis in cholestatic livers by mediating the initial inflammation of the liver.

Electroporative alpha-MSH gene transfer attenuates thioacetamide-induced murine hepatic fibrosis by MMP and TIMP modulation

Hepatic fibrosis represents a process of healing and scarring in response to chronic liver injury. alpha-Melanocyte-stimulating hormone (alpha-MSH) is a 13-amino-acid peptide with potent anti-inflammatory effects. We have previously demonstrated that alpha-MSH gene therapy protects against thioacetamide (TAA)-induced acute liver failure. Therefore, the aim of this study is to investigate whether alpha-MSH gene therapy possesses antihepatic fibrogenic effect. Liver fibrosis was induced by long-term TAA administration in mice. alpha-Melanocyte-stimulating hormone expression plasmid was delivered via electroporation after liver fibrosis was established. Our results showed that alpha-MSH gene therapy attenuated liver fibrosis in TAA-treated mice. Reverse transcription polymerase chain reaction revealed that alpha-MSH gene therapy attenuated the liver transforming growth factor-beta1, collagen alpha1 and cell adhesion molecule mRNA upregulation. Following gene transfer, the expression of alpha-smooth muscle actin and cyclooxygenase-2 were both significantly attenuated. Further, alpha-MSH significantly increased matrix metalloproteinase (MMP), while tissue inhibitors of matrix metalloproteinase (TIMPs) were inactivated. In summary, alpha-MSH gene therapy reversed established liver fibrosis in mice and prevented the upregulated fibrogenic and pro-inflammatory gene responses after TAA administration. Its collagenolytic effect might be attributed to MMP and TIMP modulation. Hence, alpha-MSH gene therapy may be an effective therapeutic modality against liver fibrosis with potential clinical use.