Co-occurrence of metabolic syndrome and chronic alcohol consumption is increasing worldwide. The present study investigated the effect of the chemical chaperone 4-phenylbutyric acid (PBA)-which has been shown to alleviate dietary steatohepatitis caused by endoplasmic reticulum (ER) stress-on chronic-plus-binge ethanol (EtOH)-induced liver injury in a mouse model of obesity.

Male KK-A^y mice (8 weeks old) were fed a Lieber-DeCarli diet (5% EtOH) for 10 days. Some mice were given PBA intraperitoneally (120 mg/kg body weight, daily) during the experimental period. On day 11, mice were gavaged with a single dose of EtOH (4 g/kg body weight). Control mice were given a dextrin gavage after being pair-fed a control diet. All mice were then serially euthanized before or at 9 hours after gavage.

Chronic-plus-binge EtOH intake induced massive hepatic steatosis along with hepatocyte apoptosis and inflammation, which was reversed by PBA treatment. Administration of PBA also suppressed chronic-plus-binge EtOH-induced up-regulation of ER stress-related genes including binding immunoglobulin protein (Bip), unspliced and spliced forms of X-box-binding protein-1 (uXBP1 and sXBP1, respectively), inositol trisphosphate receptor (IP3R), and C/EBP homologous protein (CHOP). Further, it blocked chronic-plus-binge EtOH-induced expression of the oxidative stress marker heme oxygenase-1 (HO-1) and 4-hydroxynonenal. Chronic EtOH alone (without binge) increased Bip and uXBP1, but it did not affect those of sXBP1, IP3R, CHOP, or HO-1. PBA reversed the prebinge expression of these genes to control levels, but it did not affect chronic EtOH-induced hepatic activity of cytochrome P450 2E1.

Binge EtOH intake after chronic consumption induces massive ER stress-related oxidative stress and liver injury in a mouse model of obesity through dysregulation of the unfolded protein response. PBA ameliorated chronic-plus-binge EtOH-induced liver injury by reducing ER and oxidative stress after an EtOH binge.

Alcoholic liver disease (ALD) is a chronic liver disorder caused by the consumption of large amounts of alcohol. Genome-wide association studies have recently confirmed that polymorphisms in PNPLA3 predispose individuals to ALD and have identified risk loci of MBOAT7 and TM6SF2 in persons of European descent. However, the association with alcoholic liver damage has not been evaluated thus far in a Han Chinese population.

We performed a large case-control multicenter study of 507 ALD patients and 645 ethnically matched healthy controls. Five SNPs were genotyped using matrix-assisted laser desorption/ionization time of flight mass spectrometry, and association analysis was performed using PLINK 1.07 software.

The rs738409 in the PNPLA3 gene was found to be significantly associated with ALD in allele and genotype frequencies (p = 6.25 × 10^-14 and p = 9.05 × 10^-13). The frequencies of the risk allele G in rs738409 were notably higher in ALD compared to controls (odds ratio = 1.93, 95% confidence interval = 1.63-2.28). The current study showed that the genotype frequencies of three genetic models were also statistically significant (p = 1.07 × 10^-13, p = 9.3 × 10^-8, and p = 1.57 × 10^-12). Additionally, the G-allele of rs738409 was associated with a variety of clinical manifestations such as elevated alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyl transpeptidase (GGT), and mean corpuscular volume (MCV) in the patients with ALD.

In a Han Chinese population, the present study confirmed that PNPLA3 polymorphism rs738409 was more likely to influence the susceptibility to ALD. However, no statistically significant differences for the allele and genotype frequencies of rs626283, rs641738 in MBOAT7, rs10401969 in SUGP1 and rs58542926 in TM6SF2 were found between ALD patients and healthy controls.

To evaluate the association of lifestyle with the development of alcoholic liver disease (ALD) or alcoholic pancreatitis (AlcP).

A case-control study was conducted on 80 patients attending a tertiary university hospital, subdivided into three groups: ALD (n = 34), AlcP (n = 21) and a control (CT) group (n = 25) of alcohol abusers without clinical evidence of hepatic or pancreatic disease. Participants were interviewed regarding alcohol consumption, tobacco use and diet. A physical examination was concomitantly performed and we had access to their complementary investigation.

We included 10 females and 70 males (mean age 57 ± 10 years). The pure amount of alcohol consumed by the ALD group was significantly higher than the AlcP group, regarding both daily (grams/day) and lifetime (kilograms) consumptions (p = .018 and p = .009, respectively); no statistically significant differences were seen with the CT group. We found no differences regarding the beverage type or drinking outside meals. Smoking was very common in every study group, with higher consumptions and a significantly higher prevalence of ever smokers in the AlcP group, in comparison with ALD and CT patients (p = .033 and p = .036, respectively). There were significant differences in the patients' eating habits before the onset of disease between groups (p < .001), with ALD subjects reporting a less abundant diet and AlcP a more abundant diet in the past; most of the controls had unchanged habits.

We found differences in lifestyle between ALD and AlcP, not considered sufficient to explain the subjects' susceptibility to one disease or the other.

The present work aimed to investigate the activities and underlying mechanisms of dioscin against alcoholic liver fibrosis (ALF). In vivo liver fibrosis in mice was induced by an alcoholic liquid diet, and in vitro studies were performed on activated HSC-T6 and LX2 cells treated with lipopolysaccharide. Our results showed that dioscin significantly attenuated hepatic stellate cells (HSCs) activation, improved collagen accumulation, and attenuated inflammation through down-regulating the levels of myeloid differentiation factor 88 (MyD88), nuclear factor κB (NF-κB), interleukin (IL)-1, IL-6 and tumour necrosis factor-α by decreasing Toll-like receptor (TLR)4 expression both in vivo and in vitro. TLR4 overexpression was also decreased by dioscin, leading to the markedly down-regulated levels of MyD88, NF-κB, transforming growth factor-β1 (TGF-β1), α-smooth muscle actin (α-SMA) and type I collagen (COL1A1) in cultured HSCs. Suppression of cellular MyD88 by ST2825 or abrogation of NF-κB by pyrrolidine dithiocarbamate eliminated the inhibitory effects of dioscin on the levels of TGF-β1, α-SMA and COL1A1. In a word, dioscin exhibited potent effects against ALF via altering TLR4/MyD88/NF-κB signaling pathway, which provided novel insights into the mechanisms of this compound as an antifibrogenic candidate for the treatment of ALF in the future.

So far, innate immune mechanisms have been recognized as the main responsible for the evolution of both alcoholic steatohepatitis (ASH) and nonalcoholic steatohepatitis (NASH). However, increasing evidence points toward the possible role of adaptive immune responses, as an additional factor in promoting hepatic inflammation in steatohepatitis. In this article, we discuss recent data involving circulating antibodies and lymphocyte-mediated responses in sustaining the progression of ASH and NASH to fibrosis, as well as the possible mechanisms implicated in favoring the onset of adaptive immunity in the setting of steatohepatitis.

Alcohol abuse predisposes individuals to the development of hepatocellular carcinoma (HCC) and synergistically heightens the HCC risk in patients infected with hepatitis C virus (HCV). The mechanisms of this synergism have been elusive until our recent demonstration of the obligatory role of ectopically expressed TLR4 in liver tumorigenesis in alcohol-fed HCV Ns5a or Core transgenic mice. CD133+/CD49f+ tumor-initiating stem cell-like cells (TICs) isolated from these models are tumorigenic in a manner dependent on TLR4 and NANOG. TICs' tumor-initiating activity and chemoresistance are causally associated with inhibition of TGF-β tumor suppressor pathway due to NANOG-mediated expression of IGF2BP3 and YAP1. TLR4/NANOG activation causes p53 degradation via phosphorylation of the protective protein NUMB and its dissociation from p53 by the oncoprotein TBC1D15. Nutrient deprivation reduces overexpressed TBC1D15 in TICs via autophagy-mediated degradation, suggesting a possible role of this oncoprotein in linking metabolic reprogramming and self-renewal.

Oxidative stress is implicated in pathogenesis of alcoholic liver disease (ALD). This study investigated the possible correlation among the erythrocyte indices of oxidative stress, the leukocyte panels of antioxidant proteins (metallothioneins), the serum biochemical parameters and the liver steatosis grade.

A total of 118 cases including 60 alcoholic subjects and 58 controls were enrolled. All the alcoholic subjects were screened for body mass index (BMI), liver steatosis, and blood chemistry and serology. The level of oxidative stress and oxidative stress-related parameters were measured in the blood and correlated with clinical findings.

Alcoholic subjects showed higher BMI, moderate/severe hepatic steatosis, increase in the levels of triglycerides, cholesterol, glucose, γ-glutamyl-transpeptidase (GGT), alanine aminotransferase (ALT), bilirubin, alpha 1 and beta 2 globulins, iron and a decrease in the levels of aspartate aminotransferase (AST) and beta 1 globulin with respect to the reference values. Moreover, alcoholic subjects showed: (i) an increase in Thiobarbituric Acid Reactive Substance (TBARS) content representing a good estimation of global oxidative stress; (ii) a stimulation of the activities of the antioxidant enzymes catalase and SOD; (iii) a modulation of expression of metallothioneins, with a down-regulation of MT-1A and an up-regulation of MT-1E isoforms.

Our data suggest that alcoholism is strongly associated with altered pattern of blood metallothioneins; this parameter combined with the score calculated by an ad hoc implemented algorithm (HePaTest) could offer a non-invasive alternative approach for evaluating alcohol-related damages and could be used in follow-up of alcoholic patients.

Alcohol abuse and obesity are two known risk factors for hepatocellular carcinoma (HCC) that also synergistically promote HBV/HCV-related carcinogenesis. TLR4, the receptor for endotoxin, participates in inflammatory processes such as M1 activation of hepatic macrophages in alcoholic liver disease. However, its role in liver carcinogenesis via ectopic expression and activation has only recently been revealed in alcohol/HCV-associated HCC models. Alcohol feeding to mice expressing the HCV Ns5a in a hepatocyte specific manner aggravates liver inflammation via activation of overexpressed TLR4 in the parenchymal cells. Long-term alcohol feeding produces liver tumors in these transgenic mice in a manner dependent on TLR4. From these mice, CD133+/CD49f+ tumor-initiating stem cell-like cells (TICs) have been isolated. These TICs exhibit self-renewal and tumorigenic activities driven by TLR4-dependent upregulation of the stem cell factor NANOG. A defective TGF-β tumor suppressor pathway is identified in the TICs and mediated by NANOG target genes Igf2bp3 and Yap1. This TGF-β pathway antagonism is responsible in part for the TICs' tumorigenic activity and chemoresistance. Conversely, mice with an attenuated TGF-β pathway due to haploinsufficiency of β2-Spectrin, spontaneously develop liver tumors and alcohol feeding increases tumor incidence in a TLR4-dependent manner. This reciprocal antagonism between TLR4 and TGF-β pathways may serve as a novel therapeutic target for HCC.

Alcohol consumption increases the small intestinal bacterial overgrowth (SIBO) and intestinal permeability of endotoxin. The endotoxin mediated inflammatory signaling plays a major role in alcoholic liver fibrosis. We evaluated the effect of ascorbic acid (AA), silymarin and alcohol abstention on the alcohol induced endotoxemia and NF-κB activation cascade pathway in guinea pigs (Cavia porcellus). Guinea pigs were administered ethanol at a daily dose of 4g/kg b.wt for 90days. After 90days, ethanol administration was stopped. The ethanol treated animals were divided into abstention, silymarin (250mg/kg b.wt) and AA (250mg/kg b.wt) supplemented groups and maintained for 30days. The SIBO, intestinal permeability and endotoxin were significantly increased in the ethanol group. The mRNA expressions of intestinal proteins claudin, occludin and zona occludens-1 were significantly decreased in ethanol group. The mRNA levels of inflammatory receptors, activity of IKKβ and the protein expressions of phospho-IκBα, NF-κB, TNF-α, TGF-β1 and IL-6 were also altered in ethanol group. The expressions of fibrosis markers α-SMA, α1 (I) collagen and sirius red staining in the liver revealed the induction of fibrosis. But the supplementation of AA could induce greater reduction of ethanol induced SIBO, intestinal barrier defects, NF-κB activation and liver fibrosis than silymarin. The possible mechanism may be the inhibitory effect of AA on SIBO, intestinal barrier defect and IKKβ, which decreased the activation of NF-κB and synthesis of cytokines. This might have led to suppression of HSCs activation and liver fibrosis.

Naturally occuring quercetin protects hepatocytes from ethanol-induced oxidative stress, and heme oxygenase-1 (HO-1) induction and carbon monoxide (CO) metabolite may be implicated in the beneficial effect. However, the precise mechanism by which quercetin counteracts CYP2E1-mediated ethanol hepatotoxicity through HO-1 system is still remained unclear. To explore the potential mechanism, herein, ethanol (4.0 g/kg.bw.) was administrated to rats for 90 days. Our data showed that chronic ethanol over-activated CYP2E1 but suppressed HO-1 with concurrent hepatic oxidative damage, which was partially normalized by quercetin (100mg/kg.bw.). Quercetin (100 μM) induced HO-1 and depleted heme pool when incubated to human hepatocytes. Ethanol-stimulated (100mM) CYP2E1 upregulation was suppressed by quercetin but further enhanced by HO-1 inhibition with resultant heme accumulation. CO scavenging blocked the suppression of quercetin only on CYP2E1 activity. CO donor dose-dependently inactivated CYP2E1 of ethanol-incubated microsome, which was mimicked by HO-1 substrate but abolished by CO scavenger. Thus, CYP2E1-mediated ethanol hepatotoxicity was alleviated by quercetin through HO-1 induction. Depleted heme pool and CO releasing limited protein synthesis and inhibited enzymatic activity of CYP2E1, respectively.

Alcohol use disorders affect millions of individuals worldwide. Alcohol consumption is directly associated with liver disease mortality and accounts for elevated social and economic costs. Alcoholic liver disease (ALD) may take the form of acute involvement (alcoholic hepatitis) or chronic liver disease (steatosis, steatohepatitis, fibrosis and cirrhosis). The severity and prognosis of alcohol-induced liver disease depends on the amount, pattern and duration of alcohol consumption, as well as on the presence of liver inflammation, diet, nutritional status and genetic predisposition of an individual. While steatosis is an almost completely benign disease, liver cirrhosis is associated with marked morbidity, mortality and life expectancy shortening. The median survival of patients with advanced cirrhosis is 1-2 years. Severe acute alcoholic hepatitis (AH) is associated with mortality as high as 50%. It has been managed with corticoids, pentoxifylline and enteral nutrition, although evidence based data are still conflicting. Some author suggest that pentoxifylline could be a better first-line treatment in patients with severe AH. Absolute abstinence is a basic condition for any treatment of acute or chronic ALD, the other therapeutical procedure being of a supportive nature and questionable significance. Acamprosate appears to be an effective treatment strategy for supporting continuous abstinence in alcohol dependent patients. Patients with advanced liver cirrhosis who demonstrably abstain can be considered for liver transplantation, which leads to a markedly prolonged life expectancy. The crucial step in ALD prevention is in the prevention of alcohol abuse, whereas the prevention of liver injury in active alcohol abusers is not clinically applicable.

Among the pathogenesis and risk factors of alcoholic liver disease (ALD) are the source of dietary fat, obesity, insulin resistance, adipokines and acetaldehyde. Translocation of Gram-negative bacteria from the gut, the subsequent effects mediated by endotoxin, and the increased production of matricellular proteins, cytokines, chemokines and growth factors, actively participate in the progression of liver injury. In addition, generation of reactive oxygen and nitrogen species and the activation of non-parenchymal cells also contribute to the pathophysiology of ALD. A key event leading to liver damage is the transition of quiescent hepatic stellate cells into activated myofibroblasts, with the consequent deposition of fibrillar collagen I resulting in significant scarring. Thus, it is becoming clearer that matricellular proteins are critical players in the pathophysiology of liver disease; however, additional mechanistic insight is needed to understand the signalling pathways involved in the up-regulation of collagen I protein. At present, systems biology approaches are helping to answer the many unresolved questions in this field and are allowing to more comprehensively identify protein networks regulating pathological collagen I deposition in hopes of determining how to prevent the onset of liver fibrosis and/or to slow disease progression. Thus, this review article provides a snapshot on current efforts for identifying pathological protein regulatory networks in the liver using systems biology tools. These approaches hold great promise for future research in liver disease.

In response to the April 2010 U.S. Food and Drug Administration's (FDA's) revision of warning labeling for over-the-counter (OTC) acetaminophen, or N-acetyl-p-aminophenol (APAP), products, the authors reviewed APAP's potential for liver toxicity.

The authors reviewed the literature in which investigators examined data related to the epidemiology of APAP-related liver toxicity, studies in which the investigators evaluated the risk factors for its occurrence and case reports. They included articles that were used by the FDA as the basis for establishing the new labeling requirements.

Findings from the literature in which investigators have examined the relationship between APAP and liver toxicity indicate several key risk factors. Foremost are the extensive use of one or more APAP-containing compounds (particularly combinations with opioid agents) and the small margin of safety between the therapeutic and toxic doses. Both of these factors lead to unintentional or intentional drug overdose. Concurrent use of alcohol may contribute to hepatotoxicity, but it may be related to behavior rather than biochemical mechanisms involved in liver damage.

The widespread use of APAP has contributed to a substantial increase in the number of cases of acute liver toxicity in the United States. Since APAP is a component of many prescription and OTC medications, unintentional overdose can occur.

APAP has numerous applications in dentistry, but if it is used conjointly for other conditions, the risk of the patient's experiencing an overdose increases. In the context of recent FDA concerns about the increased incidence of APAP-related liver toxicity, the authors provide recommendations for safe prescribing practices for APAP. Practitioners should caution patients to follow recommended dosage instructions and avoid taking multiple APAP-containing products.

Alcohol is a risk factor for chronic disease burden in developed countries. Alcoholic liver disease affects 1% of the North American population and is the second most frequent indication for liver transplantation in the United States. It is a spectrum that ranges from simple hepatic steatosis to alcoholic hepatitis to steatohepatitis and eventually cirrhosis. The clinical spectrum of alcoholic hepatitis is wide and ranges from the asymptomatic patient to overt liver failure and death. Liver biopsy as a means of prognostication in alcoholic hepatitis has mostly been replaced with less invasive scoring systems. The management of alcoholic liver disease is challenging. Abstinence is the cornerstone of therapy and should include rehabilitation with a multidisciplinary approach. No specific treatment is required in mild to moderate alcoholic hepatitis. In patients with severe hepatitis, there appears to be a moderate survival benefit from the use of either corticosteroids or pentoxifylline in the absence of contraindications to their use. Nonresponders should have steroid therapy withdrawn by day 7, as persistence with therapy is not beneficial. Orthotopic liver transplantation remains the definitive therapy for decompensated alcoholic cirrhosis despite alcohol abstinence. More studies are needed to define the optimal timing of orthotopic liver transplantation and patients at risk of alcohol relapse post-transplant. Mt Sinai J Med 76:484-498, 2009. (c) 2009 Mount Sinai School of Medicine.

Chronic ethanol consumption in the Long-Evans (LE) rat has been associated with hepatic p53 activation, and inhibition of the insulin/PI3K/AKT signal transduction cascade due to increased expression of PTEN. We hypothesize that p53 activation and altered insulin signaling may influence the susceptibility of rats to ethanol-induced liver damage. Furthermore, p53 not only activates programmed cell death pathways and suppresses hepatocellular survival signals, but also promotes gluconeogenesis to increase systemic insulin resistance due to a novel metabolic function.

Fischer (F), Sprague-Dawley (SD) and LE rats were fed ethanol-containing or control liquid diet for 8 weeks. Histopathological and biochemical changes were assessed.

Here, we demonstrate that chronic ethanol feeding in rats promotes p53 activation, hepatic steatosis, oxidative stress, PUMA, and PTEN expression, which contribute to hepatocellular death and diminished insulin signaling in the liver. Such changes are pronounced in the LE, less prominent in SD, and virtually absent in the F rat strain. More importantly, there is activation of Tp53-induced glycolysis and apoptosis regulator (TIGAR) in the ethanol-fed LE rat. This event generates low hepatic fructose-2,6-bisphosphate (Fru-2,6-P₂) levels, reduced lactate/pyruvate ratio and may contribute to increased basal glucose turnover and high residual hepatic glucose production during euglycemic hyperinsulinemic clamp.

p53 activation correlates with the susceptibility to ethanol-induced liver damage in different rat strains. p53 not only orchestrates apoptosis and suppresses cell survival, but by activating TIGAR and decreasing hepatic Fru-2,6-P₂) levels it promotes insulin resistance and therefore, contributes to the metabolic abnormalities associated with hepatic steatosis.

Chronic liver diseases (CLDs) represent a major cause of morbidity and mortality worldwide. In all etiologies of CLDs, staging of liver fibrosis is essential for both prognosis and management. Until a few years ago, liver biopsy was the only tool for the diagnosis of liver fibrosis in patients with CLDs. However, liver biopsy is an invasive and costly procedure. More recently, various serum biomarkers and laboratory tests have been proposed as surrogates of liver histology. Due to inadequate diagnostic accuracy or to lack of sufficient validation, guidelines still do not recommend them as a substitute for liver biopsy that is still considered the gold standard for the diagnosis of liver fibrosis. Notably, non-invasive serum biomarkers, when combined, may reduce by 50%-80% the number of liver biopsies needed for correctly classifying hepatic fibrosis. However, liver biopsy cannot be avoided completely, but should be used in those cases in which non-invasive methods show poor accuracy. In this view, serum biomarkers and liver biopsy represent a union between laboratory medicine and hepatology.

A neurotransmitter, norepinephrine (NE), amplifies the mitogenic effect of epidermal growth factor (EGF) in the liver by acting on the alpha(1)-adrenergic receptor coupled with G protein, Galpha(h). However, the molecular mechanism is not well understood. Galpha(h) is known as a transglutaminase 2 (TG2), a cross-linking enzyme implicated in hepatocyte proliferation. We investigated the effect of NE on EGF-induced cell proliferation and TG2 activity using hepatocytes isolated in periportal and perivenous regions of the liver, which differ in proliferative capacity. Periportal hepatocytes (PPH) and perivenous hepatocytes (PVH) were isolated by the digitonin-collagenase perfusion technique. EGF or NE receptor binding was analyzed by Scatchard analysis. Changes in NE-induced DNA synthesis, EGF receptor (EGFR) dimerization and phosphorylation, and TG2 activity were measured. NE enhanced EGF-induced DNA synthesis, EGF-induced EGFR dimerization, and its phosphorylation in PVH but not in PPH. [(3)H]NE binding studies indicated that PVH was found to have a greater affinity and number of receptors than PPH. Furthermore, NE treatment decreased TG2 activity and increased phospholipase C activity in PVH although TG2 level showed no change. These results suggest that NE-induced amplification of EGF-induced DNA synthesis especially in PVH is caused by upregulation of EGFR activation through the switching of function from TG2 to Galpha(h).

Reactive oxygen and nitrogen species (ROS and RNS) are produced by metabolism of normal cells. However, in liver diseases, redox is increased thereby damaging the hepatic tissue; the capability of ethanol to increase both ROS/RNS and peroxidation of lipids, DNA, and proteins was demonstrated in a variety of systems, cells, and species, including humans. ROS/RNS can activate hepatic stellate cells, which are characterized by the enhanced production of extracellular matrix and accelerated proliferation. Cross-talk between parenchymal and nonparenchymal cells is one of the most important events in liver injury and fibrogenesis; ROS play an important role in fibrogenesis throughout increasing platelet-derived growth factor. Most hepatocellular carcinomas occur in cirrhotic livers, and the common mechanism for hepatocarcinogenesis is chronic inflammation associated with severe oxidative stress; other risk factors are dietary aflatoxin B(1) consumption, cigarette smoking, and heavy drinking. Ischemia-reperfusion injury affects directly on hepatocyte viability, particularly during transplantation and hepatic surgery; ischemia activates Kupffer cells which are the main source of ROS during the reperfusion period. The toxic action mechanism of paracetamol is focused on metabolic activation of the drug, depletion of glutathione, and covalent binding of the reactive metabolite N-acetyl-p-benzoquinone imine to cellular proteins as the main cause of hepatic cell death; intracellular steps critical for cell death include mitochondrial dysfunction and, importantly, the formation of ROS and peroxynitrite. Infection with hepatitis C is associated with increased levels of ROS/RNS and decreased antioxidant levels. As a consequence, antioxidants have been proposed as an adjunct therapy for various liver diseases.

We reported previously that oats supplementation prevents gut leakiness and alcoholic steatohepatitis (ASH) in our rat model of alcoholic liver disease. Because oxidative stress is implicated in the pathogenesis of both alcohol-induced gut leakiness and ASH, and because oats have antioxidant properties, we tested the hypothesis that oats protect by preventing alcohol-induced oxidative damage to the intestine. Male Sprague-Dawley rats were gavaged for 12 weeks with alcohol (starting dose of 1 g/kg increasing to 6 g/kg/day over the first 2 weeks) or dextrose, with or without oats supplementation (10 g/kg/day). Oxidative stress and injury were assessed by measuring colonic mucosal inducible nitric-oxide synthase (iNOS) (by immunohistochemistry), nitric oxide (colorimetric assay), and protein carbonylation and nitrotyrosination (immunoblotting). Colonic barrier integrity was determined by assessing the integrity of the actin cytoskeleton (immunohistochemistry) and the integrity of tight junctions (electron microscopy). Oats supplementation prevented alcohol-induced up-regulation of iNOS, nitric oxide overproduction in the colonic mucosa, and increases in protein carbonyl and nitrotyrosine levels. This protection was associated with prevention of ethanol (EtOH)-induced disorganization of the actin cytoskeleton and disruption of tight junctions. We conclude that oats supplementation attenuates EtOH-induced disruption of intestinal barrier integrity, at least in part, by inhibiting EtOH-induced increases in oxidative stress and oxidative tissue damage. This inhibition prevents alcohol-induced disruption of the cytoskeleton and tight junctions. This study suggests that oats may be a useful therapeutic agent--a nutraceutical--for the prevention of alcohol-induced oxidative stress and organ dysfunction.

Because only 30% of alcoholics develop alcoholic liver disease (ALD), a factor other than heavy alcohol consumption must be involved in the development of alcohol-induced liver injury. Animal and human studies suggest that bacterial products, such as endotoxins, are the second key co-factors, and oxidant-mediated gut leakiness is one of the sources of endotoxemia. Probiotics have been used to prevent and treat diseases associated with gut-derived bacterial products and disorders associated with gut leakiness. Indeed, "probiotic"Lactobacillus rhamnosus has been successfully used to treat alcohol-induced liver injury in rats. However, the mechanism of action involved in the potential beneficial effects of L. rhamnosus in alcohol liver injury is not known. We hypothesized that probiotics could preserve normal barrier function in an animal model of ALD by preventing alcohol-induced oxidative stress and thus prevent the development of hyperpermeability and subsequent alcoholic steatohepatitis (ASH). Male Sprague-Dawley rats were gavaged with alcohol twice daily (8 gm/kg) for 10 weeks. In addition, alcoholic rats were also treated with once daily gavage of either 2.5 x 10(7) live L. rhamnosus Gorbach-Goldin (LGG) or vehicle (V). Intestinal permeability (baseline and at 10 weeks) was determined using a sugar bolus and GC analysis of urinary sugars. Intestinal and liver tissues were analyzed for markers of oxidative stress and inflammation. In addition, livers were assessed histologically for severity of ASH and total fat (steatosis). Alcohol+LGG (ALC+LGG)-fed rats had significantly (P< or =.05) less severe ASH than ALC+V-fed rats. L. rhamnosus Gorbach-Goldin also reduced alcohol-induced gut leakiness and significantly blunted alcohol-induced oxidative stress and inflammation in both intestine and the liver. L. rhamnosus Gorbach-Goldin probiotic gavage significantly ameliorated ASH in rats. This improvement was associated with reduced markers of intestinal and liver oxidative stress and inflammation and preserved gut barrier function. Our study provides a scientific rationale to test probiotics for treatment and/or prevention of alcoholic liver disease in man.

Alcoholic liver disease still represents an important cause for death and disability in most well-developed countries and is becoming a leading cause of disease in developing countries. It is now increasingly clear that, besides the formation of acetaldehyde, alcohol effects on the liver include oxidative stress, disturbances in methionine metabolism, endoplasmic reticulum stress, inflammatory/immune responses and adipokine imbalances. This article will discuss the most recent findings on the mechanisms by which alcohol abuse causes hepatic steatosis and steatohepatitis, and now it contributes to the progression of fibrosis. Although still incomplete, these data shed new light on the multifactorial pathogenesis of alcoholic liver disease and open new possibilities in the understanding of how gender and genetic factors can influence disease progression.

One prime feature of alcoholic liver disease (ALD) is iron accumulation in hepatic macrophages/Kupffer cells (KC) associated with enhanced NF-kappaB activation. Our recent work demonstrates a peroxynitrite-mediated transient rise in intracellular labile iron (ILI) as novel signaling for endotoxin-induced IKK and NF-kappaB activation in rodent KC. The present study investigated the mechanism of KC iron accumulation and its effects on ILI response in experimental ALD. We also tested ILI response in human blood monocytes. Chronic alcohol feeding in rats results in increased expression of transferrin (Tf) receptor-1 and hemochromatosis gene (HFE), enhanced iron uptake, an increase in nonheme iron content, and accentuated ILI response for NF-kappaB activation in KC. Ex vivo treatment of these KC with an iron chelator abrogates the increment of iron content, ILI response, and NF-kappaB activation. The ILI response is evident in macrophages derived from human blood monocytes by PMA treatment but not in vehicle-treated monocytes, and this differentiation-associated phenomenon is essential for maximal TNF-alpha release. PMA-induced macrophages load iron dextran and enhance ILI response and TNF-alpha release. These effects are reproduced in KC selectively loaded in vivo with iron dextran in mice and more importantly aggravate experimental ALD. Our results suggest enhanced iron uptake as a mechanism of KC iron loading in ALD and demonstrate the ILI response as a function acquired by differentiated macrophages in humans and as a priming mechanism for ALD.

To update the reader with advances in epidemiology, genetics, detection, pathogenesis and therapy of alcohol-related liver disease.

Ill-health due to alcohol abuse is improving in some nations but deteriorating in others. Oxidative and nitrosative stress are key to the pathogenesis of alcoholic liver disease, and there is now greater emphasis than previously on their development and role of cytochrome P450 2E1, on mitochondrial stress and disruption, (including elucidation of mitochondrial protection mechanisms) disturbance of signaling pathways and involvement of extrahepatic mediators like adiponectin. Treatment of alcoholic liver disease has stagnated, but transplantation is still favored and debated for end-stage cirrhosis.

Basic and clinical research into the mechanisms of alcoholic liver disease is making headway, but has yet to produce safe and effective therapies for alcoholic hepatitis and for reversing cirrhosis.

To investigate the association of alcohol dose, duration of drinking and obesity with abnormal alcohol-related liver injury indicators, the prevalence of alcohol-related liver injury in the island population of China.

Randomized multistage stratified cluster sampling from the island population of China was used in the population-based case-control study. Then interview, physical examination, laboratory assessments and ultrasonography were done.

Daily alcohol intake > or = 20 g, duration of drinking > or = 5 years and obesity were closely related to alcohol-related liver injury (P < 0.05). The odds-ratio (OR) (95% CI) was 1.965 (1.122-3.442), 3.412 (1.789-6.507) and 1.887 (1.261-2.824), respectively. The prevalence rate of alcohol-related liver injury in > or = 20 g daily alcohol intake group and < 20 g daily alcohol intake group was 37.14% and 12.06%, respectively. The prevalence rate of alcohol-related liver injury in > or = 5 years drinking group and < 5 years drinking group was 34.44% and 8.53%, respectively. No significant dose-response relation was found between daily alcohol intake and abnormal alcohol-related liver injury indicators as well as between duration of drinking and abnormal alcohol-related liver injury indicators. There was no significant difference in the prevalence of alcohol-related liver injury between beer drinking group and yellow rice wine drinking group, hard liquor drinking group, multiple drinking group.

The risk threshold of daily alcohol intake is 20 g and duration of drinking inducing alcohol-related liver injury 5 years in the island population of China. Liver injury induced by obesity should be concerned.