interleukin-8 and Non-alcoholic-Fatty-Liver-Disease

Oxidative stress and inflammation are involved in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Bayberries contain high levels of polyphenols that possess antioxidative and anti-inflammatory properties in vitro. The purpose of this study was to investigate whether the consumption of bayberry juice beneficially alters the levels of oxidative, inflammatory, and apoptotic biomarkers in young individuals with features of NAFLD.. In this randomized, placebo-controlled, double-blind, crossover study, 44 participants (ages 18-25 y) were given 250 mL of either bayberry juice or placebo twice daily for 4 wk. Several anthropometric characteristics were measured, and fasting blood samples were drawn before and after each intervention period. The levels of plasma glucose, insulin, lipids, and some NAFLD-related biomarkers were determined.. No significant effects on the anthropometric parameters and the homeostasis model assessment for insulin resistance were observed. Compared with placebo, the consumption of bayberry juice significantly decreased the plasma levels of protein carbonyl groups (P = 0.038), tumor necrosis factor-α (P < 0.001), and interleukin-8 (P = 0.022). The apoptosis markers analysis revealed significant differences between the treatment and the placebo in the levels of tissue polypeptide-specific antigen (P < 0.001) and cytokeratin-18 fragment M30 (P < 0.001).. The consumption of bayberry juice for a period of 4 wk can protect against NAFLD in young adults by improving the plasma antioxidant status and inhibiting the inflammatory and apoptotic responses that are involved in this disease.

Topics: Adolescent; Adult; Anthropometry; Antioxidants; Apoptosis; Beverages; Biomarkers; Blood Glucose; Cross-Over Studies; Double-Blind Method; Fatty Liver; Female; Fruit; Humans; Inflammation; Insulin; Insulin Resistance; Interleukin-8; Male; Myrica; Non-alcoholic Fatty Liver Disease; Oxidative Stress; Plant Extracts; Polyphenols; Tumor Necrosis Factor-alpha; Young Adult

We performed this study to examine the metabolic differences arising from higher liver fat accumulation in obese Hispanic adolescents, with a particular focus on circulating levels of adipocytokines and insulin resistance.. Forty-one obese Hispanic adolescents (15.3 ± 1.0 years, body mass index percentile: 97.0 ± 3.9) were assessed for: visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and hepatic fat fraction (HFF) by magnetic resonance imaging; fasting measures of serum glucose, insulin and adipocytokines; homeostasis model assessment of insulin resistance (HOMA-IR); and insulin sensitivity (SI) and the acute insulin response to glucose (AIR) by intravenous glucose tolerance test. Subjects with normal levels of HFF (below 5%; n = 25) were compared to those with HFF > 5% (n = 16).. The two groups differing in HFF were similar for total body fat, VAT and SAT. The group with HFF > 5% had significantly (P < 0.05) higher interleukin-8 (IL-8) (6.1 ± 1.6 vs. 3.2 ± 0.4 pg mL(-1) ), NGF (30.2 ± 9.9 vs. 13.9 ± 1.6 pg mL(-1) ), HOMA-IR (8.8 ± 1.1 vs. 5.5 ± 0.5), AIR (1869 ± 206 vs. 1092 ± 165) and a tendency for lower SI (1.2 ± 0.4 vs. 2.1 ± 0.3; P = 0.06), with no significant differences in any of other factors measured.. These data suggest that elevated liver fat is most closely associated with elevated serum IL-8 and NGF levels as well as increased AIR and HOMA-IR. These elevated factors may play significant roles in the metabolic abnormalities associated with elevated liver fat in obese Hispanics.

Topics: Adipokines; Adolescent; Blood Glucose; Body Composition; California; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Fatty Liver; Female; Glucose Tolerance Test; Hispanic or Latino; Humans; Inflammation; Insulin; Insulin Resistance; Interleukin-8; Male; Nerve Growth Factor; Non-alcoholic Fatty Liver Disease; Obesity; Patient Education as Topic

Nonalcoholic steatohepatitis (NASH) can progress to cirrhosis and even hepatocellular carcinoma (HCC). The incidence of NASH-associated HCC is increasing, posing a serious public health threat. Unfortunately, the underlying pathological mechanisms, including the possible differences between neoplastic and non-neoplastic lesions, remain largely unknown. Previously, we reported a dietary mouse NASH model with a choline-deficient, methionine-lowered, L-amino-acid-defined, high-fat diet containing shortening without trans fatty acids (CDAA-HF-T[-]), which rapidly induces fibrosis and proliferative lesions in the liver. This study aimed to develop a mouse CDAA-HF-T(-) model capable of assessing NASH-associated hepatocarcinogenesis and identifying key signaling factors involved in its underlying mechanisms. Multiple large masses, histopathologically hepatocellular adenomas and carcinomas, and hemangiosarcomas were detected in the liver samples of mice fed CDAA-HF-T(-) for 52 or 63 weeks, along with highly advanced fibrosis and numerous foamy, phagocytic macrophages in the adjacent nontumoral area. Multiple metastatic nodules were found in the lungs of one of the animals, and lymphoid clusters were found in all CDAA-HF-T(-) group mice. In the Ingenuity Pathways Analysis of RNA expression data, the CDAA-HF-T(-) feeding revealed common signal changes in nontumoral and tumoral liver tissues, including increased IL-8 and RhoGTPases signaling and decreased lipid metabolism. Meanwhile, macrophage inflammatory protein 2 (MIP-2) expression levels were upregulated in nontumoral liver tissue from the end of Week 13 of CDAA-HF-T(-) feeding to the end of Week 63. On the other hand, MIP-2 was expressed on macrophages in non-tumor areas and hepatocytes in tumor areas. Therefore, the CDAA-HF-T(-) mouse model is useful for assessing NASH and NASH-associated hepatocarcinogenesis, and IL-8 signaling plays important roles in NASH-associated carcinogenesis and cirrhosis, but it may also play different roles in nontumoral liver tissue and tumorigenesis.

Topics: Amino Acids; Animals; Carcinoma, Hepatocellular; Cell Transformation, Neoplastic; Choline; Choline Deficiency; Diet, High-Fat; Disease Models, Animal; Fibrosis; Interleukin-8; Liver; Liver Cirrhosis; Liver Neoplasms; Methionine; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease

Nonalcoholic steatohepatitis (NASH) is an advanced stage of fatty liver disease characterized by liver damage, inflammation, and fibrosis. Although neutrophil infiltration is consistently observed in the livers of patients with NASH, the precise role of neutrophil-recruiting chemokines and infiltrating neutrophils in NASH pathogenesis remains poorly understood. Here, we aimed to elucidate the role of neutrophil infiltration in the transition from fatty liver to NASH by examining hepatic overexpression of interleukin-8 (IL8), a major chemokine responsible for neutrophil recruitment in humans. Mice fed a high-fat diet (HFD) for 3 months developed fatty liver without concurrent liver damage, inflammation, and fibrosis. Subsequent infection with an adenovirus overexpressing human IL8 for an additional 2 weeks increased IL8 levels, neutrophil infiltration, and liver injury in mice. Mechanistically, IL8-induced liver injury was associated with the upregulation of components of the NADPH oxidase 2 complex, which participate in neutrophil oxidative burst. IL8-driven neutrophil infiltration promoted macrophage aggregate formation and upregulated the expression of chemokines and inflammatory cytokines. Notably, IL8 overexpression amplified factors associated with fibrosis, including collagen deposition and hepatic stellate cell activation, in HFD-fed mice. Collectively, hepatic overexpression of human IL8 promotes neutrophil infiltration and fatty liver progression to NASH in HFD-fed mice.

Topics: Animals; Diet, High-Fat; Disease Models, Animal; Inflammation; Interleukin-8; Liver; Liver Cirrhosis; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease

Individuals carrying the risk variant p.I148M of patatin-like phospholipase domain-containing protein 3 (PNPLA3) have a higher susceptibility to fatty liver diseases and associated complications, including HCC, a cancer closely linked to chronic inflammation. Here, we assessed circulating cytokine profiles for patients with chronic liver diseases genotyped for PNPLA3.. Serum concentrations of 22 cytokines were measured by multiplex sandwich-ELISA. The cohort comprised 123 individuals: 67 patients with NAFLD without cirrhosis (57 steatosis, 10 NASH), 24 patients with NAFLD with cirrhosis, 21 patients with HCC (15 cirrhosis), and 11 healthy controls. Receiver operator characteristic analyses were performed to assess the suitability of the cytokine profiles for the prediction of steatosis, cirrhosis, and HCC.. HGF, IL-6, and IL-8 levels were increased in patients, with ∼2-fold higher levels in patients with cirrhosis versus healthy, while platelet derived growth factor-BB (PDGF-BB) and regulated on activation, normal T cell expressed and secreted (RANTES) showed lower concentrations compared to controls. Migration inhibitory factor and monocyte chemoattractant protein-1 (MCP-1) were found at higher levels in NAFLD samples (maximum: NAFLD-cirrhosis) versus healthy controls and HCC samples. In receiver operator characteristic analyses, migration inhibitory factor, IL-8, IL-6, and monocyte chemoattractant protein-1 yielded high sensitivity scores for predicting noncirrhotic NAFLD (vs. healthy). The top combination to predict cirrhosis was HGF plus PDGF-BB. Migration inhibitory factor performed best to discriminate HCC from NAFLD; the addition of monokine induced gamma (MIG), RANTES, IL-4, macrophage colony-stimulating factor (M-CSF), or IL-17A as second parameters further increased the AUC values (> 0.9). No significant impact of the PNPLA3I148M allele on cytokine levels was observed in this cohort.. Cytokines have biomarker potential in patients with fatty liver, possibly suited for early HCC detection in patients with fatty liver. Patients carrying the PNPLA3 risk allele did not present significantly different levels of circulating cytokines.

Topics: Alleles; Becaplermin; Carcinoma, Hepatocellular; Chemokine CCL2; Cytokines; Humans; Interleukin-6; Interleukin-8; Liver Cirrhosis; Liver Neoplasms; Non-alcoholic Fatty Liver Disease

The aim: To determine the role of selenium and Selenoprotein P in the intensification of inflammation processes, deviations of the functional state of the liver and the progression of changes in its parenchyma in patients with NAFLD and hypertension.. Material and methods: Study included 100 gender and age matched NAFLD patients: 49 (67.3 % women) hypertensive (main group) and 51 (58.8 % women) non-hypertensive NAFLD patients. 20 individuals (55.0 % women) formed control group. Diagnosis of NAFLD and hypertension was made according to respective guidelines. All patients underwent measurement of liver transferases, selenium, Selenoprotein P, IL-8 and IL-10.. Results: In both study groups, ALT and AST levels were significantly predominant in patients with steatohepatitis than steatosis. Increase in IL-8 and IL-10 was found in main study groups but not in subgroup analysis. In hypertensive NAFLD patients with steatosis, ALT correlated with selenium and Selenoprotein P. A direct correlation was between the de Ritis index and IL-8. Selenium correlated with IL-8 but not IL-10. Selenoprotein P correlated inversely with IL-8 and directly with IL-10.. Conclusions: Intensification of inflammation and depletion of antioxidant protection under presence of hypertension deepen redox violations in NAFLD patients. Such changes can be only partially compensated by anti-inflammatory and antioxidative activity. Selenium and Selenoprotein P are important substances in progression of NAFLD and should be assessed regarding diagnosis and treatment of NAFLD patients.

Topics: Antioxidants; Female; Humans; Hypertension; Inflammation; Interleukin-8; Male; Non-alcoholic Fatty Liver Disease; Selenium; Selenoprotein P

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent cause of liver disease in children. Mercury (Hg), a ubiquitous toxic metal, has been proposed as an environmental factor contributing to toxicant-associated fatty liver disease.. We investigated the effect of prenatal exposure to Hg on childhood liver injury by combining epidemiological results from a multicenter mother-child cohort with complementary in vitro experiments on monocyte cells that are known to play a key role in liver immune homeostasis and NAFLD. We used data from 872 mothers and their children (median age, 8.1 years; interquartile range [IQR], 6.5-8.7) from the European Human Early-Life Exposome cohort. We measured Hg concentration in maternal blood during pregnancy (median, 2.0 μg/L; IQR, 1.1-3.6). We also assessed serum levels of alanine aminotransferase (ALT), a common screening tool for pediatric NAFLD, and plasma concentrations of inflammation-related cytokines in children. We found that prenatal Hg exposure was associated with a phenotype in children that was characterized by elevated ALT (≥22.1 U/L for females and ≥25.8 U/L for males) and increased concentrations of circulating IL-1β, IL-6, IL-8, and TNF-α. Consistently, inflammatory monocytes exposed in vitro to a physiologically relevant dose of Hg demonstrated significant up-regulation of genes encoding these four cytokines and increased concentrations of IL-8 and TNF-α in the supernatants.. These findings suggest that developmental exposure to Hg can contribute to inflammation and increased NAFLD risk in early life.

Topics: Adult; Alanine Transaminase; Child; Cohort Studies; Cytokines; Disease Susceptibility; Exposome; Female; Humans; Inflammation; Interleukin-1beta; Interleukin-6; Interleukin-8; Male; Maternal Exposure; Mercury; Non-alcoholic Fatty Liver Disease; Pregnancy; Prenatal Exposure Delayed Effects; Tumor Necrosis Factor-alpha

Neutrophil infiltration is a hallmark of nonalcoholic steatohepatitis (NASH), but how this occurs during the progression from steatosis to NASH remains obscure. Human NASH features hepatic neutrophil infiltration and up-regulation of major neutrophil-recruiting chemokines (e.g., chemokine [C-X-C motif] ligand 1 [CXCL1] and interleukin [IL]-8). However, mice fed a high-fat diet (HFD) only develop fatty liver without significant neutrophil infiltration or elevation of chemokines. The aim of this study was to determine why mice are resistant to NASH development and the involvement of p38 mitogen-activated protein kinase (p38) activated by neutrophil-derived oxidative stress in the pathogenesis of NASH.. Inflamed human hepatocytes attracted neutrophils more effectively than inflamed mouse hepatocytes because of the greater induction of CXCL1 and IL-8 in human hepatocytes. Hepatic overexpression of Cxcl1 and/or IL-8 promoted steatosis-to-NASH progression in HFD-fed mice by inducing liver inflammation, injury, and p38 activation. Pharmacological inhibition of p38α/β or hepatocyte-specific deletion of p38a (a predominant form in the liver) attenuated liver injury and fibrosis in the HFD. Genetic ablation of hepatic p38a increases simple steatosis but ameliorates oxidative stress-driven NASH, indicating that p38α plays distinct roles depending on the disease stages, which may set the stage for investigating p38α as a therapeutic target for the treatment of NASH.

Topics: Animals; Chemokine CXCL1; Diet, High-Fat; Disease Models, Animal; Drug Discovery; Fatty Liver; Gene Deletion; Hepatocytes; Humans; Interleukin-8; Mice; Mitogen-Activated Protein Kinase 14; Neutrophil Infiltration; Non-alcoholic Fatty Liver Disease; Oxidative Stress; Severity of Illness Index

The progression of nonalcoholic fatty liver disease (NAFLD) to nonalcoholic steatohepatitis (NASH) is linked to systemic inflammation. Currently, two of the aspects that need further investigation are diagnosis and treatment of NASH. In this sense, the aim of this study was to assess the relationship between circulating levels of cytokines, hepatic expression of toll-like receptors (TLRs), and degrees of NAFLD, and to investigate whether these levels could serve as noninvasive biomarkers of NASH. The present study assessed plasma levels of cytokines in 29 normal-weight women and 82 women with morbid obesity (MO) (subclassified: normal liver (

Topics: Adipokines; Adult; Bariatric Surgery; Case-Control Studies; Female; Humans; Interleukin-8; Liver; Middle Aged; Non-alcoholic Fatty Liver Disease; Obesity, Morbid; Toll-Like Receptor 2; Toll-Like Receptor 4

Chronic hepatic inflammation is an important pathogenic mediator of nonalcoholic fatty liver disease (NAFLD) that contributes to disease severity. It is commonly suggested that autophagy dysfunction may be an underlying cause of nonalcoholic fatty liver disease. However, the exact role of autophagy in lipid metabolism remains controversial. There has been a growing interest in the role of folate supplementation for the treatment and/or prevention of NAFLD. We aimed in this study to investigate the effects of different doses of folate supplementation on several immune markers and autophagy trying to explore the complex role of IL-22 and autophagy in NAFLD.. Fifty Wistar rats were randomly separated into experimental (n = 40) and control groups (n = 10), which were fed for eight weeks with a high-fat diet (HFD) containing 40% fats or a standard diet, respectively. The experimental group was further subdivided into four subgroups where the first subgroup was left untreated while the other three were treated with different doses of folate (50, 100, and 150 μg/kg of body weight, respectively). At the end of the experimental period, animals from each group were sacrificed for blood and tissue analyses.. NAFLD rats showed decreased IL-22 serum levels and increased LC3B expression as compared to controls. Folate treatment was significantly associated with improvement in disease parameters, reduced presence of the pro-inflammatory cytokines TNF-α and CXCL8 and LC3B expression, and increased IL-22 levels in a dose-dependent manner.. These results highlight the capacity of folate to modulate the production of several pro-inflammatory cytokines and autophagy thereby having a favorable impact disease progression.

Topics: Animals; Autophagy; Diet, High-Fat; Dietary Supplements; Disease Models, Animal; Dose-Response Relationship, Immunologic; Folic Acid; Gene Expression Regulation; Interleukin-22; Interleukin-8; Interleukins; Lipid Metabolism; Liver; Male; Microtubule-Associated Proteins; Non-alcoholic Fatty Liver Disease; Rats; Rats, Wistar; Tumor Necrosis Factor-alpha

Insulin resistance and inflammation are strongly linked to non-alcoholic fatty liver disease (NAFLD) as a feature of the metabolic syndrome. Furthermore, the role of dysregulation of miR-34a, miR-451, and miR-33a in pathogenesis and progression of NAFLD has been identified. trans-Chalcone is a simple chalcone with anti-diabetic and anti-inflammatory activities. However, to the best of our knowledge, miRNA-dependent mechanisms of these protective effects under pathologic conditions are not understood. Thus, this study, for the first time, aimed to evaluate the effects of trans-Chalcone on miR-34a, miR-451, and miR-33a signaling pathways in the liver of high-fat (HF) emulsion-fed rats. To this aim, twenty-one rats were randomly and equally divided into three groups: control, which was gavaged with 10% tween 80; HF, which was gavaged with HF emulsion and 10% tween 80; and HF + trans-Chalcone (HF + TC), which was gavaged with HF emulsion and trans-Chalcone. Then, circulating levels of glucose and insulin were measured and used for the calculation of HOMA-IR. Hepatic expression levels of miR-34a, miR-451, miR-33a, SIRT1, and ABCA1 and also protein levels of ABCA1 and IL-8 were assayed. In this study, trans-chalcone increased hepatic cholesterol efflux and prevented insulin resistance and liver inflammation in HF emulsion-fed rats. These protective effects were modulated through the down-regulation of miR-34a and its associated elevation of SIRT1, the up-regulation of miR-451 which was associated with a reduction in IL-8, and the inhibition of miR-33a which was related to the elevation of ABCA1 in the liver of HF emulsion-fed rats. Therefore, trans-Chalcone exerts its beneficial effects by targeting hepatic miR-34a-, miR-451-, and miR-33a-related pathways.

Topics: Animals; ATP Binding Cassette Transporter 1; Chalcones; Cholesterol; Diet, High-Fat; Humans; Insulin; Insulin Resistance; Interleukin-8; Male; MicroRNAs; Non-alcoholic Fatty Liver Disease; Rats; Rats, Wistar; Sirtuin 1; Triglycerides

To investigate the mechanism and effect of Psoralea corylifolia(PC) in the treatment of NAFLD in juvenal mice. The NAFLD model in juvenal mice was established by feeding high-fat diet. Then PC herbal granules (at low and high dose) were administered for 5 weeks. Blood glucose (FBG, PG-1 h/2 h), blood lipid (TC, TG, HDL-C, LDL-C), fasting insulin, liver function (ALT, AST) were examined. HOMA-IR was calculated. Hepatic histological changes were observed. The content of TG, inflammatory factor (TNF-α, IL-8) and protein expressions of CD44, NF-κB p65, p-NF-κB p65 in hepatic tissues were determined. The ratio of p-NF-κB p65 to NF-κB p65 (p-p65/p65) was calculated. The result showed that compared with the model group, both PC treatment groups showed reduction in hepatic steatosis, inflammatory cell infiltration and fibroplasia in portal area. HOMA-IR, ALT, AST, FBG, PG-2 h, TC, TG, LDL-C concentrations and hepatic TG content were also significantly decreased, with the reduction of TNF-α, IL-8 contents, CD44 expression and p-p65/p65 ratio in hepatic tissues (P<0.01). High-dose PC group had a better effect than low-dose group (P<0.01, P<0.05). In conclusion, PC is effective in treating hepatic injury, glucolipid metabolism disturbances and fibrosis in juvenal NAFLD mice. The mechanism may be related to inhibition of inflammation and down-regulation of the activation of hepatic NF-κB.

Topics: Animals; Diet, High-Fat; Drugs, Chinese Herbal; Interleukin-8; Liver; Mice; Non-alcoholic Fatty Liver Disease; Psoralea; Transcription Factor RelA; Tumor Necrosis Factor-alpha

Several studies explored the association between vitamin D status and nonalcoholic fatty liver disease with contradictory results. We aimed to investigate the association between vitamin D status, inflammatory cytokines and liver fibrosis in nonalcoholic fatty liver disease patients. Two hundred nineteen nonalcoholic fatty liver disease patients and 166 age- and gender- matched healthy controls were recruited for this study. Serum 25(OH)D was measured by radioimmunoassay. Serum interleukin-8 and transforming growth factor-β1 were measured using ELISA. Serum 25(OH)D was only marginally decreased in nonalcoholic fatty liver disease patients. Interestingly, serum 25(OH)D was markedly reduced in nonalcoholic fatty liver disease patients with advanced liver fibrosis compared to nonalcoholic fatty liver disease patients with indeterminate liver fibrosis and no advanced fibrosis. Logistic regression analysis showed that there was an inverse association between serum 25(OH)D and severity of liver fibrosis in nonalcoholic fatty liver disease patients. Further analysis showed that serum interleukin-8 was elevated in nonalcoholic fatty liver disease patients, the highest interleukin-8 in patients with advanced fibrosis. An inverse correlation between serum 25(OH)D and interleukin-8 was observed in nonalcoholic fatty liver disease patients with and without liver fibrosis. Although serum transforming growth factor-β1 was slightly elevated in nonalcoholic fatty liver disease patients, serum transforming growth factor-β1 was reduced in nonalcoholic fatty liver disease patients with advanced fibrosis. Unexpectedly, a positive correlation between serum 25(OH)D and transforming growth factor-β1 was observed in nonalcoholic fatty liver disease patients with advanced fibrosis. In conclusion, low vitamin D status is associated with advanced liver fibrosis in nonalcoholic fatty liver disease patients. Interleukin-8 may be an important mediator for hepatic fibrosis in nonalcoholic fatty liver disease patients with low vitamin D status.

Topics: Adult; Case-Control Studies; Female; Humans; Interleukin-8; Liver Cirrhosis; Male; Middle Aged; Non-alcoholic Fatty Liver Disease; Transforming Growth Factor beta1; Vitamin D; Vitamin D Deficiency

Non-alcoholic fatty liver disease (NAFLD) is a common disorder characterized by excessive hepatic fat accumulation, production of reactive oxygen species (ROS), inflammation and potentially resulting in non-alcoholic steatohepatitis (NASH), cirrhosis and end-stage liver disease. Recently, we have shown that niacin significantly prevented hepatic steatosis and regressed pre-existing steatosis in high-fat fed rat model of NAFLD. To gain further insight into the cellular mechanisms, this study investigated the effect of niacin on human hepatocyte fat accumulation, ROS production, and inflammatory mediator IL-8 secretion.. Human hepatoblastoma cell line HepG2 or human primary hepatocytes were first stimulated with palmitic acid followed by treatment with niacin or control for 24 h.. The data indicated that niacin (at 0.25 and 0.5 mmol/L doses) significantly inhibited palmitic acid-induced fat accumulation in human hepatocytes by 45-62%. This effect was associated with inhibition of diacylglycerol acyltransferase 2 (DGAT2) mRNA expression without affecting the mRNA expression of fatty acid synthase (FAS) and carnitine palmitoyltransferase 1 (CPT1). Niacin attenuated hepatocyte ROS production and it also inhibited NADPH oxidase activity. Niacin reduced palmitic acid-induced IL-8 levels.. These findings suggest that niacin, through inhibiting hepatocyte DGAT2 and NADPH oxidase activity, attenuates hepatic fat accumulation and ROS production respectively. Decreased ROS production, at least in part, may have contributed to the inhibition of pro-inflammatory IL-8 levels. These mechanistic studies may be useful for the clinical development of niacin and niacin-related compounds for the treatment of NAFLD/NASH and its complications.

Topics: Diacylglycerol O-Acyltransferase; Hepatocytes; Humans; Hypolipidemic Agents; Interleukin-8; Lipid Metabolism; Niacin; Non-alcoholic Fatty Liver Disease; Oxidative Stress; Palmitic Acid; Primary Cell Culture; Reactive Oxygen Species

Peroxisome proliferator-activated receptor (PPAR) α/γ may control lipid metabolism and inflammatory response by regulating the downstream target genes, and play a crucial role in the process of non-alcoholic steatohepatitis (NASH) formation, but the difference and interaction between PPARα and PPARγ are poorly understood. The rat model with NASH was established by orally feeding high-fat and high-sucrose emulsion for 6weeks. The results shown that after the model rats were simultaneously treated with PPARα/γ agonists, the total cholesterol (TC), triglyceride (TG) and inflammatory cytokine levels in serum and hepatic tissue, the hepatic steatosis and inflammatory cellular infiltration were decreased, and were consistent with the results of hepatic lipogenic gene and nuclear factor (NF)-κB protein expressions. Conversely, these indexes were increased by PPARα/γ antagonist treatment. Compared with the model group, the serum free fatty acid (FFA) level was increased in the PPARα agonist-treated group, decreased in the PPARγ agonist-treated group, and unchanged in the PPARα/γ agonists-treated group. The hepatic FFA level was low in the PPARα/γ agonists-treated groups, but no significant variation in the PPARα/γ antagonists-treated groups. The increments of hepatic reduced glutathione (GSH) and superoxide dismutase (SOD) contents in the PPARα/γ agonists-treated groups were accompanied by decreased hepatic malondialdehyde (MDA) content. These findings demonstrated that PPARα/γ activation might decrease the hepatic lipid accumulation, oxidative stress and inflammatory cytokine production, and PPARγ could counterbalance the adverse effect of PPARα on circulating FFA. It was concluded that the integrative application of PPARα and PPARγ agonists might exert a synergic inhibitory effect on NASH formation through the modulation of PPARα/γ-mediated lipogenic and inflammatory gene expressions.

Topics: Anilides; Animals; Chemokine CCL2; Cytokines; Disease Models, Animal; Fatty Acids, Nonesterified; Fenofibrate; Gene Expression Regulation; Glutathione; Indoles; Inflammation; Interleukin-6; Interleukin-8; Lipid Metabolism; Liver; Male; Malondialdehyde; NF-kappa B; Non-alcoholic Fatty Liver Disease; Oxidative Stress; PPAR alpha; PPAR gamma; Rats; Rats, Sprague-Dawley; Rosiglitazone; Superoxide Dismutase; Thiazolidinediones; Tumor Necrosis Factor-alpha

Nonalcoholic fatty liver disease (NAFLD) is a clinicopathologic syndrome of which the main feature is diffuse macrovesicular hepatic steatosis caused by deposition of excessive free fatty acid and triglyceride in liver parenchyma.. To observe the efficacy of Tiopronin in treatment of severe nonalcoholic fatty liver disease (NAFLD).. 30 patients with severe NAFLD were treated with Tiopronin for 3 months. 30 healthy people were selected as control. The body mass index (BMI) and plasma levels of endotoxin (ET), leptin, IL-6 and IL-8 were measured before and after treatment.. The serum levels of ET, leptin, IL-6 and IL-8 in severe NAFLD group were significantly higher than those in control group (p < 0.05). After treatment with Tiopronin, these indexes were significantly lower than before (p < 0.05).. The intestinal endotoxemia (IETM) occurs in patients with severe NAFLD. Leptin, IL-6 and IL-8 play important roles in pathogenesis of NAFLD. Tiopronin can reduce the levels of ET, leptin, IL-6 and IL-8 for treatment of NAFLD.

Topics: Adult; Body Mass Index; Endotoxins; Female; Humans; Interleukin-6; Interleukin-8; Leptin; Male; Non-alcoholic Fatty Liver Disease; Tiopronin; Triglycerides

As an inhibitor of the nuclear receptor subfamily 2, group C, member 2 signaling pathway, juxtaposed with another zinc finger gene 1 (JAZF1) has been shown to be involved in gluconeogenesis, lipid metabolism, and insulin sensitivity. However, its role in hepatic lipogenesis and chronic low-grade inflammation leading to nonalcoholic fatty liver disease remains unknown. The aim of this study was to examine whether JAZF1 overexpression in vivo or in vitro can protect against palmitic acid (PA)-induced and high-fat diet (HFD)-induced systemic inflammatory responses, and the potential mechanism of this process. JAZF1 overexpression vector was transfected into PA-treated IAR-20 hepatocytes. The mRNA expression levels of proinflammatory cytokines were measured by real-time quantitative PCR, and stress-activated protein kinase activities were measured by immunoblotting. For in vivo studies, JAZF1 transgenic mice were fed an HFD for 12 weeks. Liver tissue was obtained for histological examination, real-time RT-PCR, and western blot analysis. PA significantly increased the expression levels of tumor necrosis factor-α, monocyte chemotactic protein-1 and interleukin-8 mRNA in IAR-20 hepatocytes in a dose-dependent and time-dependent manner. Treatment with JAZF1 or stress-activated protein kinase inhibitors inhibited PA-induced tumor necrosis factor-α, monocyte chemotactic protein-1 and interleukin-8 expression in these cells. In JAZF1-treated cells, the decreased expression of proinflammatory cytokines was accompanied by decreased p38 mitogen-activated protein kinase and c-Jun N-terminal kinase phosphorylation and increased nuclear factor-κB inhibitor-α protein levels, similarly to the role of signaling inhibitors. In vivo, HFD-induced expression of proinflammatory cytokines was markedly attenuated in JAZF1-Tg mice as compared with controls. This attenuation was accompanied by decreased activation of c-Jun N-terminal kinase, p38 mitogen-activated protein kinase, and nuclear factor-κB. These data provide evidence for the important role of JAZF1 in preventing lipogenesis and systemic inflammation-related disease.

Topics: Animals; Chemokine CCL2; Co-Repressor Proteins; Cytokines; Diet, High-Fat; DNA-Binding Proteins; Fatty Liver; Interleukin-8; Intracellular Signaling Peptides and Proteins; Mice; Mice, Inbred C57BL; Mice, Transgenic; Neoplasm Proteins; Non-alcoholic Fatty Liver Disease; Palmitic Acid; Proteins; Signal Transduction; Tumor Necrosis Factor-alpha

Obesity is associated with chronic low-grade inflammation perpetuated by visceral adipose. Other organs, particularly stomach and intestine, may also overproduce proinflammatory molecules. We examined the gene expression patterns in gastric tissue of morbidly obese patients with nonalcoholic fatty liver disease (NAFLD) and compared the changes in gene expression in different histological forms of NAFLD. Stomach tissue samples from 20 morbidly obese NAFLD patients who were undergoing sleeve gastrectomy were profiled using qPCR for 84 genes encoding inflammatory cytokines, chemokines, their receptors, and other components of inflammatory cascades. Interleukin 8 receptor-beta (IL8RB) gene overexpression in gastric tissue was correlated with the presence of hepatic steatosis, hepatic fibrosis, and histologic diagnosis of nonalcoholic steatohepatitis (NASH). Expression levels of soluble interleukin 1 receptor antagonist (IL1RN) were correlated with the presence of NASH and hepatic fibrosis. mRNA levels of interleukin 8 (IL8), chemokine (C-C motif) ligand 4 (CCL4), and its receptor chemokine (C-C motif) receptor type 5 (CCR5) showed a significant increase in patients with advanced hepatic inflammation and were correlated with the severity of the hepatic inflammation. The results of our study suggest that changes in expression patterns for inflammatory molecule encoding genes within gastric tissue may contribute to the pathogenesis of obesity-related NAFLD.

Topics: Adult; Chemokine CCL4; Chemokines; Cytokines; Fatty Liver; Female; Gastric Mucosa; Humans; Inflammation; Interleukin 1 Receptor Antagonist Protein; Interleukin-8; Liver; Liver Cirrhosis; Male; Middle Aged; Non-alcoholic Fatty Liver Disease; Receptors, CCR5; Receptors, Interleukin-8B; Stomach

Resistin is a cysteine-rich protein, which is abundantly expressed at the site of inflammation, and acts as a regulator of the NF-kB-dependent cytokine cascade. The aim of this study was to evaluate resistin levels in relation to inflammatory mediators, disease phenotype and autoantibody status in a spectrum of pathological conditions of the gastrointestinal tract. Resistin levels were measured with an ELISA in sera originated from 227 patients and 40 healthy controls (HC). Fifty patients diagnosed with non-alcoholic fatty liver disease (NAFLD), 53 ulcerative colitis (UC), 51 Crohn's disease (CD), 46 autoimmune hepatitis (AIH) and 27 primary sclerosing cholangitis (PSC) were included. The sera were analysed with respect to biochemical parameters of systemic inflammation and liver function and to the presence of antibodies to nuclear antigens (ANA), mitochondria (AMA) and smooth muscle (SMA). Compared with HC, resistin levels were raised in AIH (P = 0.017) and PSC (P = 0.03); compared with NAFLD, levels were elevated in CD (P = 0.041), AIH (P < 0.001) and PSC (P < 0.001). Patients with elevated levels of resistin were more often treated with corticosteroids, but no difference was found between active disease and clinical remission. Resistin levels were significantly higher in ANA-positive individuals compared with ANA-negative (P = 0.025). Resistin levels were directly correlated with IL-6 (r = 0.30, P = 0.02) and IL-8 (r = 0.51, P < 0.001). Elevated levels of resistin were prominent in patients with hepatobiliary inflammation and were associated with breach of self-tolerance, i.e. ANA positivity. Thus, we propose that resistin may be an important marker of disease severity in autoantibody-mediated gastrointestinal inflammatory diseases.

Topics: Adult; Aged; Antibodies, Antinuclear; Biomarkers; Cholangitis, Sclerosing; Disease Progression; Fatty Liver; Gene Expression Regulation; Hepatitis; Humans; Immune Tolerance; Inflammation Mediators; Inflammatory Bowel Diseases; Interleukin-6; Interleukin-8; Male; Middle Aged; Non-alcoholic Fatty Liver Disease; Resistin