interleukin-8 and Liver-Diseases--Alcoholic

The ubiquitin-proteasome system has come to be known as a vital constituent of mammalian cells. The proteasome is a large nonlysosomal enzyme that acts in concert with an 8.5 kDa polypeptide called ubiquitin and a series of conjugating enzymes, known as E1, E2 and E3, that covalently bind multiple ubiquitin moieties in a polyubiquitin chain to protein substrates in a process called ubiquitylation. The latter process targets protein substrates for unfolding and degradation by the 26S proteasome. This enzyme system specifically recognizes and degrades polyubiquitylated proteins, many of which are key proteins involved in cell cycle regulation, apoptosis, signal transduction, and antigen presentation. The 26S proteasome contains a cylinder-shaped 20S catalytic core that, itself, degrades proteins in an ATP- and ubiquitin-independent manner. The 20S form is actually the predominant enzyme form in mammalian cells. Proteolysis by the constitutive 20S proteasome is vital in removing oxidized, misfolded and otherwise modified proteins. Such degradation is critical as a means of cellular detoxification, as intracellular accumulation of damaged and misfolded proteins is potentially lethal. Studies have shown that inhibition of proteasome activity can lead to cell death. Ethanol and its metabolism cause partial inhibition of the proteasome. This leads to a number of pleiotropic effects that can affect a variety of cellular processes. This critical review describes important aspects of ethanol metabolism and its influence on the proteasome. The review will summarize recent findings on: (1) the interactions between the proteasome and the ethanol metabolizing enzyme, CYP2E1; (2) the dynamics of proteasome inhibition by ethanol in animal models and cultured cells; (3) ethanol-elicited suppression of proteasome activity and its effect on signal transduction; (4) The role of proteasome inhibition in cytokine production by liver cells; and (5) ethanol elicited suppression of peptide hydrolysis and the potential effects on antigen presentation. While the principal focus is on alcohol-induced liver injury, the authors foresee that the findings presented in this review will prompt further research on the role of this proteolytic system in other tissues injured by excessive alcohol consumption.

Topics: Animals; Central Nervous System Depressants; Cytochrome P-450 CYP2E1; Ethanol; Histocompatibility Antigens Class I; Humans; Interleukin-8; Liver Diseases, Alcoholic; Proteasome Endopeptidase Complex; STAT3 Transcription Factor; Ubiquitin

Interleukin-8 (IL-8), a cytokine produced by a host of cells including monocytes, macrophages, Kupffer cells and hepatocytes, can activate neutrophils. Peripheral neutrophilia and liver neutrophil infiltration are frequently noted in patients with alcoholic liver disease (ALD). Serum IL-8 levels are markedly elevated in patients with alcoholic hepatitis compared with those in patients with alcoholic cirrhosis, alcoholic fatty liver and non-alcoholic liver disease. The levels are also elevated in patients who die of hepatic failure and correlate with biochemical and histologic parameters and severity of liver injury. Patients with high serum IL-8 had a higher mortality rate than those with lower levels. In liver tissue from patients with ALD, local IL-8 levels also correlated with the degree of neutrophil infiltration. Serum IL-8 levels decreased gradually with abstinence from alcohol. Ethanol can increase plasma endotoxin, a potent inducer of tumor necrosis factor (TNF)-alpha and IL-1. Subsequently, TNF-alpha and IL-1, together with endotoxin, stimulate circulating and local IL-8 in ALD. Activated IL-8 then mediates neutrophil infiltration, a pivotal process in the pathogenesis of ALD. IL-8 levels might reflect the stage and severity of ALD and might serve as a predictor of survival in patients with alcoholic hepatitis. The development of agents with an anti-IL-8 effect is promising for the therapy of ALD.

Topics: Humans; Interleukin-8; Liver Diseases, Alcoholic

Recently, it was reported that there may be an activation of the inflammatory response system in detoxified alcohol-dependent patients without apparent liver disease (AWLD). The aims of the present study were to examine serum zinc (Zn) concentrations, total serum protein (TSP) and patterns obtained in the electrophoretically separated protein fractions in relation to serum interleukin-6 (IL-6) and IL-8 concentrations in detoxified AWLD patients. Zn, TSP, SP electrophoresis, and serum IL-6 and IL-8 concentrations were determined in detoxified AWLD patients and age-matched healthy volunteers. Serum Zn, TSP and the serum concentrations of albumin (Alb) and the beta fraction were significantly lower in detoxified AWLD patients than in healthy volunteers. The percentage of the alpha2 fraction was significantly higher in detoxified AWLD patients. Lower serum Zn in detoxified AWLD patients was attributable to lowered serum Alb. Lower serum Alb was significantly and negatively correlated to increased serum IL-8. The percentage of the alpha1 and alpha2 fractions were significantly and positively related to serum IL-6 and IL-8. The results show that there is an in vivo activation of the inflammatory response system in detoxified AWLD patients and that lower serum Zn may be causally related to lower serum Alb.

Topics: Adult; Alcoholism; Blood Protein Electrophoresis; Cytokines; Female; Humans; Interleukin-6; Interleukin-8; Liver Diseases, Alcoholic; Male; Serum Albumin; Zinc

In the context of gut leakiness and translocation of microbial products in alcohol-associated liver disease (ALD), it is possible that systemic and liver inflammation involve the activation of circulating monocyte through gut-derived factors. We explored the association between monocytes, microbial translocation, systemic inflammation, and ALD.. Patients with alcohol use disorder following a rehabilitation program were compared with healthy controls. We determined the circulating number and proportion of monocyte subsets by FACS. The activation of signaling pathways by gut-derived microbes was analyzed by quantitative PCR in isolated monocytes. Cytokines secretion by monocytes and phagocytosis were assessed in vitro. Serum microbial translocation markers and cytokines were measured by ELISA and multiplex assay, respectively. ALD severity and liver inflammatory responses were analyzed in liver biopsies by various methods.. In patients with alcohol use disorder, the number of blood monocytes increased compared with controls. Monocytes from patients with alcohol use disorder upregulated IL-1β and IL-8 together with toll-like receptor 2 and downstream AP-1, while fungal sensor CARD9 was downregulated. IL-1β and IL-8 were actively secreted upon stimulation in vitro with the toll-like receptor 2 ligand peptidoglycan. Exposure with Escherichia coli confirmed preserved bacterial phagocytic activity. In contrast, Candida albicans stimulation leads to downregulation of IL-1β and TNFα compared with controls. Systemic cytokines and monocyte changes correlated with microbial translocation. Hepatic IL-1β and IL-8 increased with ALD severity together with liver macrophage activation and upregulation of chemokines involved in monocyte attraction.. Our results point to the contribution of activated monocytes to systemic inflammation and ALD. Monocytes likely infiltrate the liver, transform into monocyte-derived macrophages and release IL-1β and IL-8 in response to peptidoglycan and toll-like receptor 2 activation.

Topics: Alcoholism; Cytokines; Humans; Inflammation; Interleukin-8; Liver Diseases, Alcoholic; Monocytes; Peptidoglycan; Toll-Like Receptor 2

(1) Background: Fibrosis in early-stage alcohol-associated liver disease (ALD) is commonly under-diagnosed in routine clinical practice. This study characterized the liver-injury and cell death response in alcohol use disorder (AUD) patients with ALD who also exhibited fibrosis and assessed the efficacy of standard of care (SOC) treatment in the improvement in liver injury. (2) Methods: Forty-eight heavy-drinking AUD patients aged 21−65 yrs. without clinical manifestations of liver injury were grouped by Fibrosis-4 (FIB-4) score, as negative (Gr.1 < 1.45, n = 21) or positive (Gr.2 ≥ 1.45, n = 27). Patients received 2-weeks (2 w) inpatient SOC. Data on demographics, drinking patterns, liver-injury, immune markers, and liver cell death (K18s) markers were analyzed at baseline (BL) and after 2 w SOC. (3) Results: Lifetime drinking (LTDH, yrs.) and acute heavy drinking (Heavy Drinking Days Past 90 Days [HDD90]) markers were significantly higher in Gr.2 vs. Gr.1. BL ALT, AST, AST:ALT and K18M65 were considerably higher in Gr.2. Dysregulated gut dysfunction and elevated immune activity were evident in Gr.2 characterized by TNF-α, IL-8 and LPS levels. After SOC, Gr.2 showed improvement in AST, ALT, AST/ALT ratio; and in the K18M65, K18M30 and K18M65/M30 ratio vs. Gr.1. The true positivity of BL IL-8 response to predict the improvement in K18M65 to normal levels among Gr.2 patients against those who did not have improvement after 2 w SOC was very high (AUROC = 0.830, p = 0.042). (4) Conclusions: Gut dysfunction, elevated cytokine response and necrotic liver cell death were elevated in AUD patients with early-stage ALD. K18 showed promise as a predictive theragnostic factor to differentiate among the AUD patients with early-stage ALD and baseline fibrosis who had improvement in liver injury against those who did not, by the levels of baseline IL-8.

Topics: Adult; Aged; Biomarkers; Humans; Interleukin-8; Liver Cirrhosis, Alcoholic; Liver Diseases, Alcoholic; Middle Aged; Young Adult

Silver (Ag) nanoparticles (NPs) are currently among one of the most widely used nanomaterials. This in turn, implies an increased risk of human and environmental exposure. Alcohol abuse is a global issue with millions of people in the general population affected by the associated adverse effects. The excessive consumption of alcohol is a prominent cause of chronic liver disease which manifest in multiple disorders. In this study, the adverse health effects of Ag NP exposure were investigated in models of alcoholic hepatic disease in vitro and in vivo. The data showed that Ag NP induced hepatic health effects were aggravated in the alcohol pretreated mice in comparison to controls with regards to an organ specific inflammatory response, changes in blood biochemistry, acute phase response and hepatic pathology. In addition, alcoholic disease influenced the organ's ability for recovery post-NP challenge. Additionally, it is demonstrated that the in vivo data correlated well with in vitro findings where ethanol pretreatment of hepatocytes resulted in significantly increased inflammatory response post-Ag NP exposure. To the best of our knowledge this is the first study of its kind to investigate nano-sized material-induced hepatic pathology in models representative of susceptible individuals (those with pre-existing alcohol liver disease) within the population. This is an area of research in the field of nanotoxicology, and in particular with regard to NP risk assessment that is almost entirely overlooked.

Topics: Acute-Phase Reaction; Animals; Antioxidants; Biomarkers; Chemical and Drug Induced Liver Injury; Ethanol; Female; Glutathione; Hep G2 Cells; Humans; Inflammation; Interleukin-8; Liver; Liver Diseases, Alcoholic; Metal Nanoparticles; Mice; Silver

Lipopolysaccharide (LPS) is suspected to trigger primary biliary cirrhosis (PBC) in susceptible individuals, yet the precise mechanism of its effect in PBC remains largely unknown. The aim of this study was to investigate altered responses to LPS ligand for Toll-like receptors (TLRs) in pathogenesis of PBC in vivo and in vitro.. In vivo, we investigated levels of LPS and pro-inflammatory cytokines in sera and expression of LPS receptors in liver tissues from 162 patients with PBC, 325 patients with other liver diseases and 80 healthy controls. In vitro, altered responses to LPS on monocytes and cultured human biliary epithelial cells (BECs) from patients with PBC were determined.. Significantly higher levels of LPS in patients with PBC were detected, compared with patients with other liver diseases and healthy controls. Immunohistochemically, expression of TLR4, CD14, CD68 and NF-κB was significantly enhanced in liver tissues from patients with PBC. Before LPS stimulation, we found significantly higher serum levels of tumor necrosis factor-α, interleukin (IL)-1β, IL-6 and IL-8 in patients with PBC than those in healthy controls. After LPS stimulation, TLR4 expression and pro-inflammatory cytokine production in CD14-positive monocytes and cultured BEC from patients with PBC increased significantly.. These results indicated that patients with PBC were prone to exhibit higher serum LPS level, hypersensitivity of monocytes and BEC to LPS, and enhanced production of pro-inflammatory cytokines. LPS altered expression of TLR4, CD14 and NF-κB on monocytes and BEC, which may be implicated in the pathogenesis and progression of PBC.

Topics: Adult; Alkaline Phosphatase; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Bilirubin; CD83 Antigen; Cells, Cultured; Cross-Sectional Studies; Epithelial Cells; Female; gamma-Glutamyltransferase; Hepatitis B, Chronic; Hepatitis, Autoimmune; Humans; Immunoglobulins; Inflammation; Interleukin-1beta; Interleukin-6; Interleukin-8; Lipopolysaccharide Receptors; Lipopolysaccharides; Liver Cirrhosis, Biliary; Liver Diseases, Alcoholic; Male; Membrane Glycoproteins; Middle Aged; Monocytes; NF-kappa B; Toll-Like Receptor 4; Toll-Like Receptors; Tumor Necrosis Factor-alpha

The influence of the immune system on the development of alcoholic liver disease has recently been the object of attention. However, the connection between alcohol consumption, altered immune response, and development of changes in the liver has not been fully explained. The aim of the present study was to evaluate serum IL-8 concentration in patients with chronic alcoholic liver disease.. 85 patients with different types of ALD and 35 healthy subjects were enrolled in the study. Serum IL-8 concentration was evaluated with the ELISA immunoenzymatic method. IL-8 in liver tissue was measured by the indirect immunofluorescence method.. There was a significant correlation between IL-8 concentration and AST, ALP, GGT, total bilirubin and albumin levels in blood serum. A significantly higher concentration of IL-8 was seen in all the groups of ALD patients. The highest values were found in patients with chronic alcoholic hepatitis, and the lowest in those with fatty liver. Significantly higher values were found in patients with ascites or encephalopathy in comparison to those without any features of portal hypertension and/or insufficiency of the liver cells. A high concentration of the tested cytokine is a disadvantageous prognostic factor in patients with ALD.. IL-8 appears to be an important factor in liver pathology in patients with ALD, especially in the development of the inflammatory process.

Topics: Ascites; Case-Control Studies; Enzyme-Linked Immunosorbent Assay; Fatty Liver, Alcoholic; Female; Fluorescent Antibody Technique, Indirect; Hepatic Encephalopathy; Hepatitis, Alcoholic; Humans; Interleukin-8; Liver; Liver Cirrhosis, Alcoholic; Liver Diseases, Alcoholic; Male; Prognosis

There is increased activity of the proinflammatory cytokine, tumor necrosis factor (TNF) in alcoholic liver disease (ALD). Hepatic neutrophil infiltration is a principal injurious manifestation of ALD. TNF can induce cellular oxidative injury directly, and indirectly by inducing neutrophil chemotactic factor (IL-8) production by hepatocytes. IL-8 activates and chemotactically attracts neutrophils to the liver where they release oxidizing substances. Patients with ALD also have decreased protective factors for cellular oxidative injury. Manganous superoxide dismutase (MnSOD) is an antioxidant protective factor. The objectives of these studies were to investigate mechanisms for induction of an injurious factor (IL-8) and a protective factor (MnSOD) in the HepG2 human hepatoma cell line. In the first set of experiments, IL-8 gene reporter constructs were used to transiently transfect a derivative (MVh2E1-9) of the HepG2 cell line which expresses P-4502E1 and metabolizes ethanol. Inactivation of the NF-kappaB and 3'NF-IL-6 DNA binding sites decreased IL-8 gene transcriptional activation in response to TNF while inactivation of the 5'NF-IL-6 binding site increased IL-8 gene transcriptional activity in response to TNF. This system may be useful to assess the effects of ethanol on TNF-induced hepatocyte IL-8 production. In the second set of experiments, HepG2 cells were cultured in 25 to 100 mmol concentrations of ethanol. Both TNF and ethanol increased HepG2 cell MnSOD activity in short-term (72 hr) cultures with ethanol. However, after long-term (10 weeks) culture with ethanol, there was no induction of MnSOD by ethanol and there was a diminished induction of MnSOD in response to TNF. Further studies are needed to assess the effect of this diminished induction of MnSOD with chronic ethanol culture on HepG2 cell susceptibility to TNF cytotoxicity. We conclude that transfected liver cell lines can be used to evaluate mechanisms for increased injurious factors and decreased protective factors in alcoholic liver injury.

Topics: Animals; Antigens, CD; Cell Line, Transformed; Enzyme Induction; Ethanol; Gene Expression Regulation; Humans; Interleukin-8; Liver Diseases, Alcoholic; Liver Neoplasms, Experimental; Neutrophils; NF-kappa B; Receptors, Interleukin; Receptors, Interleukin-8A; Superoxide Dismutase; Transfection; Tumor Cells, Cultured

Interleukin-8 (IL-8), an inflammatory cytokine that promotes neutrophil accumulation, has been implicated in the pathogenesis of alcoholic liver disease but the mechanism of its production is unknown. The ability of lipid peroxidation products, also implicated in alcoholic liver disease, to stimulate IL-8 production was studied because of their alleged role in alcoholic liver disease. Peroxidized fatty acids (arachidonic and linolenic) as well as microsomal membranes stimulated IL-8 production by peripheral blood monocytes whereas ethanol and acetaldehyde did not. Hydrocortisone (5 microg/ml) prevented the IL-8 stimulation by peroxidized fatty acids. Ethanol-induced lipid peroxidation may secondarily further alcohol-induced liver injury through IL-8 chemotaxis of neutrophils.

Topics: Acetaldehyde; alpha-Linolenic Acid; Arachidonic Acid; Ethanol; Humans; Hydrocortisone; Interleukin-8; Lipid Peroxidation; Lipopolysaccharides; Liver Diseases, Alcoholic; Malondialdehyde; Microsomes; Monocytes

Interleukin-8 (IL-8), a cytokine produced by a host of cells, including monocytes, macrophages, Kupffer cells and hepatocytes, can activate neutrophils. Peripheral neutrophilia and liver neutrophil infiltration are frequently noted in patients with alcoholic liver disease. However, the relationship between IL-8 and different stages of alcoholic liver disease is uncertain. The aim of this study is to determine if a correlation exists between circulating IL-8 levels and biochemical and histological parameters and survival in alcoholic liver disease.. Serum levels of IL-8 were determined with an enzyme-linked immunosorbent assay in 166 subjects, consisting of 30 healthy controls, 26 patients with non-alcoholic fatty liver, 15 with alcoholic fatty liver, 32 with alcoholic hepatitis, 30 with alcoholic cirrhosis, 28 with chronic hepatitis B and 5 with chronic hepatitis C.. Serum IL-8 levels were markedly elevated in patients with alcoholic hepatitis (437 +/- 51 pg/ml) when compared with all other groups (p < 0.05). Levels of IL-8 in patients with alcoholic fatty liver, alcoholic cirrhosis and viral hepatitis were higher than those in controls and in patients with non-alcoholic fatty liver. In addition, IL-8 levels were higher in patients who died (p = 0.007), and correlated with biochemical and histological parameters, and severity of liver injury: serum aspartate aminotransferase, alanine aminotransferase, total bilirubin, prothrombin time, indocyanine green retention ratio, tumor necrosis factor-alpha and peripheral neutrophil count in patients with alcoholic hepatitis. After a 2-year follow up, patients with IL-8 above 479 pg/ml had a higher mortality rate in the alcoholic hepatitis group (p = 0.033).. These findings suggest that IL-8 is activated in alcoholic liver disease, especially in alcoholic hepatitis, and is closely correlated with liver injury. IL-8 levels can reflect the stage and severity of alcoholic liver disease, and may serve as a predictor of survival in patients with alcoholic hepatitis.

Topics: Adult; Enzyme-Linked Immunosorbent Assay; Female; Humans; Interleukin-8; Liver; Liver Diseases, Alcoholic; Male; Middle Aged; Survival Analysis

Chronic alcohol consumption has been associated with suppression of a number of immune parameters. This study was designed to investigate the relationship between chronic alcohol ingestion and cessation with respect to release of interleukin-6 (IL-6) and interleukin-8 (IL-8) using highly specific and sensitive ELISA assays, as well as a functional assay, natural killer cell cytotoxic activity. ELISAs were developed to determine the amount of IL-6 and IL-8 release by peripheral blood mononuclear cells (PBMCs). Two groups of subjects were recruited: young (18-22 years old), nonalcoholic users (controls) and long-term alcoholics (35-55 years old). Blood samples were collected at time 0 from all subjects and from alcoholics 28 days after treatment had begun and alcohol use had ceased. Then mitogen-stimulated release of cytokines by peripheral blood cells was determined. The abstaining controls, and the alcoholics, after 30 days of abstinence, tended to produce lower amounts of IL-6 and IL-8, although these differences were not statistically significant. Natural killer cell activity was not statistically different between the young groups, yet appeared to increase once alcohol use discontinued. Some of the cells from the controls (abstainers) were incubated with ethanol (EtOH). Its content in sealed wells was measured after the time of incubation of PBMCs. When EtOH was serially diluted in plates, some well-well diffusion was noted, but the maximum concentration of EtOH never fell below 0.3% from an initial concentration of 0.5%, and at no time was the EtOH concentration gradient completely lost, even after 66 hr of incubation.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adolescent; Adult; Alcohol Drinking; Alcohol Withdrawal Delirium; Alcoholism; Enzyme-Linked Immunosorbent Assay; Humans; Interleukin-6; Interleukin-8; Killer Cells, Natural; Liver Diseases, Alcoholic; Male; Monocytes

Acute alcoholic hepatitis is characterized by a unique degree of liver neutrophil infiltration, often accompanied by marked peripheral neutrophilia in the absence of demonstrable bacterial or fungal infection. In this study we assayed plasma and tissue levels of a potent neutrophil activator and chemotaxin, interleukin-8, in patients with a spectrum of alcoholic liver diseases and in normal and diseased control subjects. Levels of circulating interleukin-8 were undetectable in normal subjects but highly elevated in patients with alcoholic hepatitis, particularly in those who died (geometric mean = 600 ng/L; confidence interval = 323 to 1,120 vs. geometric mean = 184 ng/L; confidence interval = 114 to 309 in survivors). Levels correlated with biochemical indicators of severe disease (bilirubin: R = 0.38; international prothrombin ratio: R = 0.28; white blood cell count: R = 0.35; creatinine: R = 0.34) and with tumor necrosis factor-alpha (R = 0.43) and soluble tumor necrosis factor receptors (p55; R = 0.59). In contrast, moderate elevations in the levels of circulating interleukin-8 were seen in alcoholic cirrhosis (geometric mean = 93 ng/L; confidence interval = 40 to 213) and in alcoholic patients undergoing alcohol withdrawal (geometric mean = 137 ng/L; confidence interval = 72 to 259). Levels in nonalcoholic inflammatory liver disease were comparatively low (geometric mean = 17 ng/L; confidence interval = 10 to 29).(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Acute Disease; Autoimmune Diseases; Female; Hepatic Encephalopathy; Hepatitis; Hepatitis, Alcoholic; Humans; Immunohistochemistry; Interleukin-8; Liver; Liver Cirrhosis, Alcoholic; Liver Diseases, Alcoholic; Male; Neutrophils; Prospective Studies; Tumor Necrosis Factor-alpha