Possible involvement of cytokine gene polymorphisms in fulminant hepatitis

BACKGROUND AND AIM: Host genetic factors have been reported as influencing the progress to fulminant hepatitis (FH). Our previous data showed the serum level of tumor necrosis factor (TNF)-alpha influenced by gene polymorphisms to be markedly increased. It was investigated whether polymorphisms in the IL-10 gene, in addition to TNF-alpha and -beta gene polymorphisms, might contribute to the pathogenesis of FH. METHODS: We analyzed 42 patients with FH, 78 patients with acute hepatitis (AH), and 149 healthy subjects (control). IL-10 polymorphism sites at promoter regions -1028, -819, -592; TNF-alpha polymorphism sites at promoter regions -1031, -863, -857, -308, -238; and TNF-beta first intron Nco1 sites were studied. IL-10 gene polymorphisms were classified into three groups: low IL-10-producing haplotypes (ATA/ATA), intermediate haplotypes (ATA or CCA/CCA), and high haplotypes (ATA/ATG or CCG). RESULTS: The allelic frequency of B2 in the TNF-beta gene was significantly higher in FH patients compared with the control group. The three groups showed no differences in polymorphisms of positions -1031, -863, -857, -308 and -238 in the TNF-alpha gene. The frequency of low IL-10-producing haplotypes tended to be higher in FH patients compared with control and that of high IL-10-producing haplotype tended to be lower in FH patients compared with control. The carrier rate with both the IL-10 haplotype and the TNF-beta gene B2/B2 was significantly higher than control. CONCLUSION: Variations of cytokine polymorphisms including IL-10 and TNF-beta genes may be attributable to the pathogenesis of FH.     

Tumor necrosis factor gene polymorphisms and clearance or progression of hepatitis B virus infection.

OBJECTIVES: We evaluated the influence of tumor necrosis factor-alpha (TNF-alpha) promoter gene polymorphisms on clearance of hepatitis B virus (HBV) and outcome of HBV chronic hepatitis. METHODS: Four TNF-alpha promoter polymorphisms (T-1031C, C-863A, G-308A, and G-238A) were evaluated by direct sequencing in 184 chronic HBV carriers hepatitis B surface antigen (HBsAg) positive and 96 controls with documented sero-clearance (HBsAg negativity, positivity for anti-HBs and anti-HBc IgG). Frequencies of single-nucleotide polymorphisms (SNPs) and haplotypes in the control group were compared with those of the chronic carrier group and with clinically defined subgroups of the latter: asymptomatic carriers, patients with compensated hepatitis, decompensated cirrhotics, and patients with hepatocellular carcinoma. Furthermore, subgroups of chronic carriers were compared among them. Results: In the chronic carrier group, the -308 G allele was more frequent in those with a family history of HBV infection (96% vs 88% of those with non-familial transmission). The G/G genotype at position -308 was found in all chronic carriers with decompensated cirrhosis but in only 78% of controls (P=0.01) and was more frequent in decompensated cirrhotics than in the other subgroups. The distribution of TNF-alpha gene polymorphisms in the carrier group was not significantly different from that in the sero-clearance control group. TNF-alpha SNPs at positions -1031/-863 and -863/-238 were in linkage disequilibrium. The TCGG haplotype (-T1031, -C863, -G308, -G238) was significantly associated with end-stage liver disease. CONCLUSION: The TNF-alpha promoter polymorphisms do not appear to be determinant of HBV sero-clearance in southern Italians. The genotype -308G/G and haplotype TCGG are associated with an unfavorable prognosis in patients with chronic HBV infection.     

Influence of inducible nitric oxide synthase polymorphisms in Japanese patients with non-alcoholic fatty liver disease

Aim:  Genetic factors as well as environmental factors play an important role in the development of non-alcoholic fatty liver disease (NAFLD). Recently, inducible nitric oxide synthase (iNOS) was significantly higher in the severest form of non-alcoholic steatohepatitis (NASH), and nitric oxide (NO) has been determined to play an important role in the process of fibrosis in NASH. In this study, we investigated iNOS gene polymorphisms for associations with NAFLD.
Methods:  A total of 115 NAFLD patients, consisting of 65 patients with NASH and 50 patients with simple steatosis, in whom a positive diagnosis had been made by liver biopsy, and 435 healthy control subjects, were recruited into this study.
Results:  We investigated 10 single nucleotide polymorphisms (SNP) of the iNOS gene, one of which, rs1060822, had the lowest P -value in the allele frequency model ( P  = 0.00078) with an odds ratio (95% confidence interval) of 0.49 (0.32–0.75). Four SNP, rs2297510, rs2297511, rs2797512 and rs1060822, were significantly associated with NAFLD, even when the most conservative Bonferroni's correction was applied. Linkage disequilibrium analysis revealed that SNP rs1060822 and three other SNP, rs2297510, rs2297511 and rs2797512, were in the same block. We also investigated associations between rs1060822 genotypes and the fibrosis index, and the results of the analysis revealed an additive increase in the fibrosis index and intrahepatic iNOS mRNA expression in the patients with the T allele of rs1060822.
Conclusion:  This is the first study to identify genetic variations in iNOS that may influence the risk of NAFLD and liver fibrosis in NAFLD.     

Predictors reflecting the pathological severity of non-alcoholic fatty liver disease: comprehensive study of clinical and immunohistochemical findings in younger Asian patients

BACKGROUND AND AIMS: The spectrum of non-alcoholic fatty liver disease (NAFLD) ranges from simple steatosis to severe steatohepatitis (NASH). The aim of our study was to identify clinical predictors distinguishing NASH from steatosis and to study the pathogenesis of NASH in a young Korean population. METHODS: Clinical and biochemical variables from 39 biopsied NAFLD patients were retrospectively analyzed. All liver biopsy specimens were immunohistochemically examined for Kupffer cells (CD68, CD14), as well as expression of tumor necrosis factor-alpha (TNF-alpha) and mitochondrial uncoupling protein 2 (UCP-2). RESULTS: There were no significant differences in serum biochemistry between the two groups (15 steatosis vs 24 NASH). There was a significant difference between the body mass index (BMI) values (kg/m(2)) of the NASH (28.4 +/- 3.4 kg/m(2)) and steatosis (25.8 +/- 2.8 kg/m(2)) patients (P < 0.025), with a BMI of 28.9 kg/m(2) representing the best threshold for distinguishing NASH from steatosis patients. BMI was significantly related to the degree of fibrosis (P < 0.01). CD68+ Kupffer cells were more common in the livers of NASH patients (P < 0.05), and TNF-alpha and UCP-2 were expressed in all NASH specimens and were related with the severity of inflammation and fibrosis (P < 0.05). CONCLUSIONS: BMI could be used to distinguish NASH from steatosis in younger Korean patients. A high BMI with a low alanine aminotransferase (ALT) value tended to suggest the presence of severe fibrosis in NASH, while the number of CD68+ Kupffer cells and the staining intensity of TNF-alpha and UCP-2 were correlated with general pathologic severity in patients with NAFLD.     

Serum cytokine and soluble cytokine receptor levels in patients with non-alcoholic steatohepatitis.

BACKGROUND: Although the pathogenesis of non-alcoholic steatohepatitis (NASH) remains poorly understood, proinflammatory cytokines seem to play an important role in the process of NASH. We have undertaken this study in order to elucidate the role of proinflammatory cytokines and their soluble receptors in NASH patients. METHODS: Serum cytokines and soluble cytokine receptors levels were determined using an enzyme-linked immunosorbent assay kit in 23 patients with NASH, 21 patients with simple steatosis, and 18 healthy volunteers. RESULTS: Patients with NASH had significantly higher serum tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) levels than did the simple steatosis patients. Similarly, when compared with simple steatosis, NASH was associated with higher soluble TNF receptor 1 (sTNFR1) and soluble IL-6 receptor (sIL-6R) levels, and a significant positive correlation was seen between the levels of sTNFR1 and aminotranferases in NASH patients. CONCLUSIONS: This study shows that circulating TNF-alpha/sTNFR1 and IL-6/sIL-6R levels are significantly increased in NASH patients as compared with simple steatosis patients and healthy volunteers, and that these increased levels may be implicated in the pathogenesis of NASH.     

Role of tumor necrosis factor-alpha and interleukin-10 promoter gene polymorphisms in leprosy

Single-nucleotide polymorphisms within the genes coding for tumor necrosis factor (TNF)-alpha and interleukin (IL)-10 have been associated with several infectious diseases. To determine whether such polymorphisms are associated with leprosy, genotyping was performed at the -308 and -238 positions of the promoter of the TNF-alpha gene in 210 and 191 patients with multibacillary (MB) leprosy, respectively; 90 and 79 patients with paucibacillary (PB) leprosy; and 92 control subjects. For the -592 and -819 positions within the promoter of the IL-10 gene, 143 patients with MB leprosy, 79 patients with PB leprosy, and 62 control subjects were included in the analysis. TNF2 allele frequency was significantly higher among control subjects than among all patients with leprosy or in the MB group (P<.05 and P<.01). For the IL-10 gene, the frequency of the homozygous -819TT genotype was significantly higher among patients than among control subjects. These data indicate that a relationship exists between TNF-alpha and IL-10 promoter polymorphisms and the development of PB leprosy.     

A polymorphism of the 5' flanking region of tumour necrosis factor alpha gene is associated with thyroid-associated ophthalmopathy in Japanese

OBJECTIVE: We have studied the polymorphism of the 5' flanking region of the tumour necrosis factor (TNF)-alpha gene in order to better understand the genetic background of autoimmune thyroid disorders and thyroid-associated ophthalmopathy. PATIENTS AND METHODS: We studied the polymorphism of the 5' flanking region of the TNF-alpha gene at positions - 1031 (T to C change, termed as - 1031C), - 863 (C to A, - 863 A), - 857 (C to T, - 857T), - 308 (G to A, - 308 A) and - 238 (G to A, - 238 A) in Japanese patients with Graves' disease [n = 173, 62 of whom had associated ophthalmopathy (American Thyroid Association (ATA) class III or greater)] and healthy control subjects (n = 575), using a polymerase chain reaction sequence-specific oligonucleotide probe method. RESULTS: The allele frequency of - 857T in the Graves' disease patients (22. 5% vs. 17.7%, OR = 1.35, P = 0.045, corrected P = 0.23) was slightly greater than in the Japanese healthy subjects, respectively. However, the difference was not statistically significant. In Graves' disease patients with evident ophthalmopathy (ATA class III or greater), the allele frequencies of - 1031C and - 863 A were significantly greater than those with no or mild ophthalmopathy (ATA class 0-II) (31.5% vs. 13.5%, OR =2.94, P < 0.0001, corrected P < 0. 0005; 23.4% vs. 11.7%, OR =2.30, P = 0.0044, corrected P = 0.022, respectively) and in control subjects. The strength of the association of the polymorphism - 1031C increased with the severity of ophthalmopathy, with odds ratios of 2.36 for ATA class III, and 5. 43 for ATA class IV-VI, respectively, compared with Graves' disease with no or mild ophthalmopathy (ATA class 0-II). Although the phenotype frequency of DRB1*0901 was not different among Graves' disease patients with or without ophthalmopathy and control subjects, the phenotype frequency of DRB1*0901(-)/-1031C(+) was significantly increased in Graves' disease patients with ophthalmopathy compared to those with no or mild ophthalmopathy (OR = 4.91, P = 0.0005) or control subjects (OR = 4.59, P < 0.0001). CONCLUSIONS: These results suggest that the - 1031C or - 863 A alleles, or a gene in linkage disequilibrium with the TNF-alpha gene, predispose to the development of ophthalmopathy in Japanese patients with Graves' disease.     

Tumor necrosis factor promoter polymorphisms in patients with rheumatoid arthritis in Taiwan

OBJECTIVE: To investigate the association of tumor necrosis factor (TNF) promoter polymorphisms with rheumatoid arthritis (RA) in Taiwan. METHODS: TNF promoter polymorphisms at positions -238, -244, -308, -376, -857, and -863 were determined in 97 patients with RA and 97 healthy controls using the PCR-RFLP method. RESULTS: The phenotypic frequency of TNF-308A was significantly lower in patients with RA than in healthy controls. This finding can only be found in HLA-DR4 negative patients, not in DR4 positive RA patients and controls. The TNF promoter polymorphisms at positions -238, -244, -308, -376, -857, and -863 were not related to the clinical manifestations of RA patients. CONCLUSION: TNF-308A itself or a neighboring gene may be a protective factor for the development of RA in the HLA-DR4 negative population in Taiwan. TNF promoter polymorphisms were not associated with the clinical manifestations of patients with RA in Taiwan.     

Beyond insulin resistance in NASH: TNF-alpha or adiponectin?

Adiponectin has antilipogenic and anti-inflammatory effects, while tumor necrosis factor alpha (TNF-alpha) reduces insulin sensitivity and has proinflammatory effects. We examined (1) the extent to which hypoadiponectinemia and TNF-alpha activation are features of nonalcoholic steatohepatitis (NASH) and (2) whether serum levels of these markers correlate with the severity of histological changes in 109 subjects with nonalcoholic fatty liver disease (NAFLD), including 80 with NASH and 29 with simple steatosis. By multivariate analysis, subjects with NASH had reduced adiponectin level and increased TNF-alpha and soluble TNF receptor 2 (sTNFR2)-but not leptin levels, compared with controls matched by age, sex, and body mass index; these differences were independent of the increased insulin resistance (by homeostasis model [HOMA-IR]) in NASH. When compared with simple steatosis, NASH was associated with lower adiponectin levels and higher HOMA-IR, but there were no significant differences in the levels of TNF-alpha and sTNFR2. The majority of subjects with steatohepatitis (77%) had adiponectin levels less than 10 microg/mL and HOMA-IR greater than 3 units, but only 33% of those with pure steatosis had these findings. HOMA-IR and low serum adiponectin were also independently associated with increased grades of hepatic necroinflammation. In conclusion, hypoadiponectinemia is a feature of NASH independent of insulin resistance. Reduced adiponectin level is associated with more extensive necroinflammation and may contribute to the development of necroinflammatory forms of NAFLD.     

Serum Ferritin Is a Clinical Biomarker in Japanese Patients with Nonalcoholic Steatohepatitis (NASH) Independent of HFE Gene Mutation

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver injury. The spectrum of NAFLD is broad, extending from simple steatosis through nonalcoholic steatohepatitis (NASH). Iron is regarded as a putative element that interacts with oxygen radicals, and high rates of hyperferritinemia and increased hepatic iron stores have been demonstrated in NASH. We investigated serum ferritin concentrations, HFE gene mutations, and insulin resistance in Japanese NASH patients and the diagnostic utility of serum ferritin concentrations as a means of distinguishing NASH. Serum ferritin concentrations were measured in 86 patients with histopathologically verified NAFLD (24 with steatosis and 62 with NASH) and 20 control subjects, they were tested for HFE gene mutations and their insulin resistance was measured. The serum ferritin concentration was significantly higher in the NASH patients than in the patients with simple steatosis (P = 0.006). There was no significant difference between the groups in HFE gene mutation (C282Y, H63D, and S65C), and the serum ferritin level was related with insulin resistance. The area under the ROC curve was 0.732 for distinguishing NASH from simple steatosis (P = 0.005; 95% CI, 0.596–0.856). In conclusion high serum ferritin concentrations are a distinguishing feature of Japanese NASH patients independent of HFE gene mutations.     

Host TNF-alpha-1031 and -863 promoter single nucleotide polymorphisms determine the risk of benign ulceration after H. pylori infection

OBJECTIVES: This study tested whether host genotypes of the tumor necrosis factor-alpha (TNF-alpha) promoter single nucleotide polymorphism (SNP) could determine clinical and histological outcomes after Helicobacter pylori infection. METHODS: A total of 524 dyspeptic patients, 424 with and 100 without H. pylori infection, were checked for TNF-alpha promoter SNP over the locus on -1031(T/C), -863(C/A), -857(C/T), -806(C/T), and -308(G/A) by sequence-specific oligonucleotide probe. Each patient received panendoscopy to take gastric biopsy to detect H. pylori infection and its related histology using the updated Sydney's system. Gastric TNF-alpha expressions were stained by immunohistochemistry. RESULTS: In H. pylori-infected patients, -1031C or -863A carriers of TNF-alpha promoter had more severe gastric neutrophil infiltration and TNF-alpha gastric staining than individuals with -1031TT or -863CC genotype, respectively (p<0.05). The multivariate logistic regression verified both -1031C and -863A carriers were independent risk factors to have duodenal ulcers and gastric ulcer without IM in the H. pylori-infected hosts (p<0.05). As compared to -863CC and -1031TT genotype combinations, the ulcer risk after H. pylori infection was 2.46 (95% CI: 1.32-4.59, p相似文献   

Tumour necrosis factor‐α promoter region polymorphisms affect the course of spontaneous HBsAg clearance

Background: This study aimed to investigate the roles of tumour necrosis factor‐α (TNF‐α) gene polymorphisms in the spontaneous clearance of HBsAg after a hepatitis B virus (HBV) infection. Methods: Polymorphisms in the TNF‐α (?1031 T to C, ?863 C to A, ?857 C to T, ?308 G to A and ?238 G to A transition) gene were evaluated in 274 chronic HBV‐infected patients and 194 patients with resolved HBV infection. The peripheral blood mononuclear cells (PBMC) isolated from 77 (28%) of the 274 chronic HBV‐infected patients with negative HBeAg and positive antibody to HBeAg were stimulated with HBcAg. Data on TNF‐α genotypes and phenotypes in subjects with/without the A allele at the TNF‐α?863 promoter single nucleotide polymorphism (rs1800630) were compared. Results: The A allele in the ?863 promoter region of the TNF‐α gene was present in 154 (56.2%) chronic HBV‐infected patients and 87 (44.8%) patients who recovered from HBV infection (odds ratio 1.58; P<0.01). The TNF‐α?863 A allele genotype predicted lower TNF‐α production by PBMC after in vitro HBcAg stimulation (P<0.02). Conclusions: The A allele at the ?863 locus of the promoter region of the TNF‐α gene predicts lower HBcAg‐inducible TNF‐α secretion. It is also associated with chronicity of HBV infection.     

Systemic inflammation in nonalcoholic fatty liver disease is characterized by elevated levels of CCL2

BACKGROUND/AIMS: To elucidate the role of systemic inflammation in nonalcoholic fatty liver disease (NAFLD). METHODS: Serum samples in 47 patients with histologically verified NAFLD (22 with simple steatosis and 25 with nonalcoholic steatohepatitis [NASH]), and in 30 age-, sex- and ethnicity-matched healthy controls, were assessed for (i) general markers of inflammation (C-reactive protein [CRP], tumor necrosis factor [TNF]-alpha, and interleukin [IL]-6), (ii) chemokines (CC-chemokine ligand [CCL] 2/monocyte chemoattractant protein [MCP]-1, CCL19 and CCL21), (iii) adipocytokines related to insulin resistance and inflammation (adiponectin and leptin) and (iv) a marker of oxidative stress (8-isoprostane-F2alpha). RESULTS: Serum levels of several inflammatory cytokines were increased in NAFLD as compared to controls, and IL-6 (P=0.017), CCL2/MCP-1 (P=0.008) and CCL19 (P=0.001), but not CRP (P=0.199), remained elevated also after correction for sex, body mass index (BMI) and age. Comparing NASH with simple steatosis, levels of TNF-alpha (P=0.024) and CCL2/MCP-1 (P=0.012) were elevated and adiponectin (in women) (P=0.001) were decreased also after adjustment for sex, BMI and presence of the metabolic syndrome. CONCLUSIONS: Our results indicate that patients with NAFLD are characterized by a low-grade systemic inflammation. The high CCL2/MCP-1 levels in NASH might be of importance for the conversion from simple steatosis to NASH.     

Attitudes of Elderly Patients to Examinations and Treatments of Gastrointestinal Symptoms

Abstract

Objective. We sought to investigate whether serum proteomic pattern analysis obtained using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI TOF-MS) may help to diagnose non-alcoholic steatohepatitis (NASH) in the setting of non-alcoholic fatty liver disease (NAFLD). Material and methods. We enrolled 80 patients with biopsy-proven NAFLD and 19 healthy comparison subjects. Patients with NAFLD were classified according to their liver histology as having definite NASH (n = 48), borderline NASH (n = 22) or simple steatosis (n = 10). Liver ultrasound scanning was performed to assess the degree of steatosis. Mass spectra of serum samples were obtained using a Ultraflex II mass spectrometer. Results. The highest accuracy for NASH diagnostics was reached using 15 peaks. Corresponding sensitivity and specificity values were 73.95% ± 3.38% and 88.71% ± 1.39%, respectively. However, mass spectra did not allow us to distinguish NASH from simple steatosis. Conclusions. We conclude that proteomic analyses of serum samples from NAFLD patients by MALDI TOF-MS do not seem to have a major clinical value for diagnosing NASH. However, the identification of 15 peaks in our study may help to further elucidate the pathophysiology of NASH and merits further investigation.     

Association between the CYBA and NOX4 genes of NADPH oxidase and its relationship with metabolic syndrome in non-alcoholic fatty liver disease in Brazilian population

Background: Oxidative stress has been implicated in the progression of severe forms of non-alcoholic fatty liver disease(NAFLD). NADPH oxidase produces reactive oxygen species. In the present study, we investigated for the first time two single nucleotide polymorphisms(SNPs) in the regulatory region of genes encoding NADPH oxidase 4(NOX4) and p22 phox(CYBA) in NAFLD.Methods: A total of 207 biopsy-proven NAFLD patients [simple steatosis(n = 27); nonalcoholic steatohepatitis(NASH)(n = 180)] were evaluated. Genomic DNA was extracted from peripheral blood cells, and polymorphisms in CYBA(unregistered) and NOX4(rs3017887) were determined by direct sequencing of PCR.Results: Associations of CYBA-675 T/A with high-density lipoprotein(HDL)(TT vs TA vs AA; P 0.01) and triglycerides(TGL)(TT vs XA; P 0.01) were observed only in NASH patients. For polymorphisms in the NOX4 gene, NOX4(rs3017887) CA + AA genotypes was significant associated with alanine aminotransferase(ALT)(CA + AA vs CC; P = 0.02). However, there was no association of SNPs in the CYBA and NOX4 genes encoding the NADPH oxidase system proteins and the presence of NASH. Regarding the clinical results, it was observed that the most advanced degrees of fibrosis occurred in patients diagnosed with type 2 diabetes mellitus(66.9% vs 37.5%, P 0.01) and those who were more obese(32.2 vs 29.0 kg/m2,P 0.01). In addition, serum glucose and insulin levels increased significantly in the presence of NASH.Conclusions: There were associations between the presence of the allele A in the NOX4 SNP and a higher concentration of ALT in the NAFLD population; between the presence of the AA genotype in the polymorphism of the CYBA-675 T/A CYBA gene and a higher level of TGL and lower HDL in NASH patients. The presence of metabolic syndrome was associated with advanced degrees of fibrosis in NAFLD patients.     

Potential role of chitotriosidase gene in nonalcoholic fatty liver disease evolution

BACKGROUND: Nonalcoholic steatohepatitis (NASH) is a liver disease characterized by steatosis and periportal and lobular inflammation. The molecular mechanisms involved in the anomalous behavior of liver cells have only partially been disclosed. Human Chitotriosidase (Chit) is a member of the chitinase family that it is mainly synthesized by activated macrophages. We investigated chitotriosidase gene expression in Kupffer cells to determine the potential implication of this enzyme in the inflammation and in the progression from uncomplicated steatosis to steatohepatitis with progressive fibrosis. METHODS: Seventy-five liver biopsies from 40 subjects with NASH, 20 with simple steatosis, and 15 controls were used to detect CHIT expression, tumor necrosis factor-alpha (TNF-alpha), alpha-smooth muscle actin (alpha-SMA), and lipid peroxidation. RESULTS: CHIT was expressed exclusively by Kupffer cells. The levels of CHIT expression were significantly higher in NASH patients than in simple steatosis patients and in the control group. In addition, we found that CHIT over-expression influenced hepatic stellate cells activation, as demonstrated by the significant correlation between CHIT and alpha-SMA expression in NASH patients. A significant correlation was observed also between CHIT, TNF-alpha and lipid peroxidation in both NASH and simple steatosis. CONCLUSION: These results suggest that CHIT over-produced by Kupffer cells may contribute to the progression of hepatic fibrosis.     

Adiponectin and its receptors in non-alcoholic steatohepatitis

BACKGROUND: Adiponectin, an adipocyte derived polypeptide, has been shown to alleviate steatosis and inflammation in mice with non-alcoholic fatty liver disease. AIM: In the present study, we wished to define liver expression of adiponectin and its receptors in morbidly obese patients undergoing bariatric surgery. Patients with non-alcoholic steatohepatitis (NASH) or simple steatosis were investigated to test whether dysregulation of this system might be involved in these disorders. PATIENTS AND METHODS: Liver mRNA expression of adiponectin and its recently cloned receptors RI and RII (adipoRI and adipoRII) were analysed by fluorescence based real time polymerase chain reaction in 13 patients with NASH and nine with simple steatosis. Adiponectin and adipoRII protein expression were assessed by immunohistochemistry in a subgroup of patients. RESULTS: Adiponectin and adipoRII mRNA expression were significantly reduced in liver biopsies of patients with NASH compared with simple steatosis while no difference was found in adipoRI mRNA expression. In NASH, adipoRII mRNA expression was negatively correlated with serum aspartate aminotransferase levels, serum alanine aminotransferase levels, and grade of fibrosis. Liver adiponectin protein expression was mainly found in endothelial cells of portal vessels and liver sinusoids whereas adipoRII expression was seen in hepatocytes only. Adiponectin and adipoRII staining were lower in biopsies of subjects with NASH compared with simple steatosis. CONCLUSION: Reduced hepatic expression of adiponectin and adipoRII might be of pathophysiological relevance in non-alcoholic fatty liver diseases.     

Clinicopathological significance of oxidative cellular damage in non-alcoholic fatty liver diseases.

Oxidative stress may play an important role in the progression of simple steatosis to non-alcoholic steatohepatitis (NASH). Oxidative stress is generated through multiple sources, including oxidation of free fatty acids, cytochrome P4502E1, iron overload, and necro-inflammatory cytokines including tumor necrosis factor-alpha. Oxidative stress may trigger damage to cellular membranes and nuclear DNA, which results in lipid peroxidation and oxidative DNA damage, respectively. Here, we present our data on intrahepatic localization and clinico-pathological significance of oxidative stress-induced cellular damage in the patients with non-alcoholic fatty liver diseases (NAFLD). Our subjects were 23 patients with non-alcoholic simple fatty liver, 17 with NASH, and 7 with normal liver (control). Hepatic expression of 4-hydroxy-2'-nonenal (HNE) and 8-hydroxydeoxyguanosine (8-OHdG), as reliable markers of lipid peroxidation and oxidative DNA damage, was in situ detected by using commercially available monoclonal antibodies. While no HNE adducts were observed in control livers, they were frequently detected in NAFLD. In NASH, the localization of the HNE adducts was in the cytoplasm of sinusoidal cells and hepatocytes with a predominance in zone 3. The grade of necro-inflammation as well as the stage of fibrosis significantly correlated with the HNE labeling index. With respect to 8-OHdG, although no 8-OHdG expression was observed in normal liver and only a few in non-alcoholic simple fatty liver, 11 of 17 patients with NASH (65%) exhibited nuclear expression of 8-OHdG in hepatocytes and sinusoidal cells in areas of active inflammation. The 8-OHdG index significantly correlated with the grade of necro-inflammation, but not with the stage of fibrosis. Our observations suggest that oxidative cellular damage occurs frequently in livers with NAFLD and may be associated with some clinico-pathological features of NAFLD including liver fibrosis and possibly, hepatocarcinogenesis.