Rifaximin on epigenetics and autophagy in animal model of hepatocellular carcinoma secondary to metabolic-dysfunction associated steatotic liver disease

BACKGROUND Prevalence of hepatocellular carcinoma(HCC)is increasing,especially in patients with metabolic dysfunctionassociated steatotic liver disease(MASLD).AIM To investigate rifaximin(RIF)effects on epigenetic/autophagy markers in animals.METHODS Adult Sprague-Dawley rats were randomly assigned(n=8,each)and treated from 5-16 wk:Control[standard diet,water plus gavage with vehicle(Veh)],HCC[high-fat choline deficient diet(HFCD),diethylnitrosamine(DEN)in drinking water and Veh gavage],and RIF[HFCD,DEN and RIF(50 mg/kg/d)gavage].Gene expression of epigenetic/autophagy markers and circulating miRNAs were obtained.RESULTS All HCC and RIF animals developed metabolic-dysfunction associated steatohepatitis fibrosis,and cirrhosis,but three RIF-group did not develop HCC.Comparing animals who developed HCC with those who did not,miR-122,miR-34a,tubulin alpha-1c(Tuba-1c),metalloproteinases-2(Mmp2),and metalloproteinases-9(Mmp9)were significantly higher in the HCC-group.The opposite occurred with Becn1,coactivator associated arginine methyltransferase-1(Carm1),enhancer of zeste homolog-2(Ezh2),autophagy-related factor LC3A/B(Map1 Lc3b),and p62/sequestosome-1(p62/SQSTM1)-protein.Comparing with controls,Map1 Lc3b,Becn1 and Ezh2 were lower in HCC and RIF-groups(P<0.05).Carm1 was lower in HCC compared to RIF(P<0.05).Hepatic expression of Mmp9 was higher in HCC in relation to the control;the opposite was observed for p62/Sqstm1(P<0.05).Expression of p62/SQSTM1 protein was lower in the RIF-group compared to the control(P=0.024).There was no difference among groups for Tuba-1c,Aldolase-B,alpha-fetoprotein,and Mmp2(P>0.05).miR-122 was higher in HCC,and miR-34a in RIF compared to controls(P<0.05).miR-26b was lower in HCC compared to RIF,and the inverse was observed for miR-224(P<0.05).There was no difference among groups regarding miR-33a,miR-143,miR-155,miR-375 and miR-21(P>0.05).CONCLUSION RIF might have a possible beneficial effect on preventing/delaying liver carcinogenesis through epigenetic modulation in a rat model of MASLD-HCC.

Beneficial effects of adenosine triphosphate-sensitive K^+ channel opener on liver ischemia/reperfusion injury

AIM:To investigate the effect of diazoxide administration on liver ischemia/reperfusion injury.METHODS:Wistar male rats underwent partial liver ischemia performed by clamping the pedicle from the medium and left anterior lateral segments for 1 h under mechanical ventilation.They were divided into 3 groups:Control Group,rats submitted to liver manipulation,Saline Group,rats received saline,and Diazoxide Group,rats received intravenous injection diazoxide(3.5 mg/kg) 15 min before liver reperfusion.4 h and 24 h after reperfusion,blood was collected for determination of aspartate transaminase(AST),alanine transaminase(ALT),tumor necrosis factor(TNF-α),interleukin-6(IL-6),interleukin-10(IL-10),nitrite/nitrate,creatinine and tumor growth factor-β1(TGF-β1).Liver tissues were assembled for mitochondrial oxidation and phosphorylation,malondialdehyde(MDA) content,and histologic analysis.Pulmonary vascular permeability and myeloperoxidase(MPO) were also determined.RESULTS:Four hours after reperfusion the diazoxide group presented with significant reduction of AST(2009 ± 257 U/L vs 3523 ± 424 U/L,P = 0.005); ALT(1794 ± 295 U/L vs 3316 ± 413 U/L,P = 0.005); TNF-α(17 ± 9 pg/mL vs 152 ± 43 pg/mL,P = 0.013; IL-6(62 ± 18 pg/mL vs 281 ± 92 pg/mL); IL-10(40 ± 9 pg/mL vs 78 ± 10 pg/mL P = 0.03),and nitrite/nitrate(3.8 ± 0.9 μmol/L vs 10.2 ± 2.4 μmol/L,P = 0.025) when compared to the saline group.A significant reduction in liver mitochondrial dysfunction was observed in the diazoxide group compared to the saline group(P < 0.05).No differences in liver MDA content,serum creatinine,pulmonary vascular permeability and MPO activity were observed between groups.Twenty four hours after reperfusion the diazoxide group showed a reduction of AST(495 ± 78 U/L vs 978 ± 192 U/L,P = 0.032); ALT(335 ± 59 U/L vs 742 ± 182 U/L,P = 0.048),and TGF-β1(11 ± 1 ng/mL vs 17 ± 0.5 ng/mL,P = 0.004) serum levels when compared to the saline group.The control group did not present alterations when compared to the diazoxide and saline groups.CONCLUSION:Diazoxide maintains liver mitochondrial function,increases liver tolerance to ischemia/reperfusion injury,and reduces the systemic inflammatory response.These effects require further evaluation for using in a clinical setting.

Pentoxifylline 通过 TNF- 合成和 TGF-1 基因表示的下面规定改进肝新生

AIM:To investigate the mechanism of pentoxifylline(PTX)improvement in liver regeneration.RESULTS:Rats were randomized into 4 groups:Control rats;Sham-sham-operation rats;Saline-70% hepatectomy plus saline solution;PTX-70%hepatectomy plus PTX.At 2 and 6 h after hepatectomy,aspartate aminotransferase,alanine aminotransferase,tumor necrosis factor(TNF)-α and interleukin-6(IL-6)serum and hepatic tissue levels were determined.Tumor growth factor(TGF)-β1 gene expression in liver tissue was evaluated 24 h after hepatectomy by quantitative reverse transcriptase polymerase chain reaction analysis.Proliferation was analyzed by mitotic index and proliferating cell nuclear antigen(PCNA)staining 48 h after hepatectomy.RESULTS:TNF-α and IL-6 serum levels increased at 2 and 6 h after hepatectomy.At 2 h after hepatectomy serum PTX was reduced but not hepatic levels of TNF-α and IL-6.A decrease in liver TGF-β1 gene expression and an increase in mitotic index and PCNA after hepatectomy were observed in the PTX treatment group in comparison to the saline group.CONCLUSION:PTX improves liver regeneration by a mechanism related to down regulation of TNF-α production and TGF-β1 gene expression.

Gut dysbiosis and systemic inflammation promote cardiomyocyte abnormalities in an experimental model of steatohepatitis

BACKGROUND Cardiovascular disease is the main cause of death in metabolic-associated fatty liver disease,and gut microbiota dysbiosis is associated with both of them.AIM To assess the relationship between gut dysbiosis and cardiovascular risk(CVR)in an experimental model of steatohepatitis.METHODS Adult male Sprague-Dawley rats were randomized to a control group(n=10)fed a standard diet and an intervention group(n=10)fed a high-fat choline-deficient diet for 16 wk.Biochemical,molecular,hepatic,and cardiac histopathology.Gut microbiota variables were evaluated.RESULTS The intervention group had a significantly higher atherogenic coefficient,Castelli’s risk index(CRI)-I and CRI-II,interleukin-1β,tissue inhibitor of metalloproteinase-1(all P<0.001),monocyte chemoattractant protein-1(P=0.005),and plasminogen activator inhibitor-1(P=0.037)than the control group.Gene expression of miR-33a increased(P=0.001)and miR-126(P<0.001)decreased in the intervention group.Steatohepatitis with fibrosis was seen in the intervention group,and heart computerized histological imaging analysis showed a significant decrease in the percentage of cardiomyocytes with a normal morphometric appearance(P=0.007),reduction in the mean area of cardiomyocytes(P=0.037),and an increase of atrophic cardiomyocytes(P=0.007).There were significant correlations between the cardiomyocyte morphometry markers and those of progression and severity of liver disease and CVR.The intervention group had a lower Shannon diversity index and fewer changes in the structural pattern of gut microbiota(both P<0.001)than controls.Nine microbial families that are involved in lipid metabolism were differentially abundant in intervention group and were significantly correlated with markers of liver injury and CVR.CONCLUSION The study found a link between gut dysbiosis and significant cardiomyocyte abnormalities in animals with steatohepatitis.

Hypolactasia is associated with insulin resistance in nonalcoholic steatohepatitis

AIM To assess lactase gene(LCT)-13910C>T polymorphisms in Brazilian non-alcoholic fatty liver disease(NAFLD) and nonalcoholic steatohepatitis(NASH) patients in comparison with healthy controls.METHODS This was a transverse observational clinical study with NAFLD patients who were followed at the Hepatology Outpatient Unit of the Hospital das Clínicas, S?o Paulo, Brazil. The polymorphism of lactase non-persistence/lactase persistence(LCT-13910C>T) was examined by PCR-restriction fragment length polymorphism technique in 102 liver biopsy-proven NAFLD patients(steatosis in 9 and NASH in 93) and compared to those of 501 unrelated healthy volunteers. Anthropometric, clinical, biochemical and liver histology data were analyzed. Continuous variables were compared using the t or Mann-Whitney tests, and categorical data were compared with the Fisher's exact test. Univariate logistic regression and multivariate logistic regression adjusted for gender and age were performed.RESULTS No differences in the LCT-13910 genotype frequencies were noted between the NAFLD patients(66.67% of the patients with steatosis were CC, 33.33% were CT, and none were TT; 55.91% of the patients with NASH were CC, 39.78% were CT, and 4.3% were TT; P = 0.941) and the healthy controls(59.12% were CC, 35.67% were CT, and 5.21% were TT) or between the steatosis and NASH patients. That is, the distribution of the lactase non-persistence/lactase persistence polymorphism(LCT-13910C>T) in the patients with NAFLD was equal to that in the general population. In the NASH patients, the univariate analysis revealed that the lactase nonpersistence(low lactase activity or hypolactasia) phenotype was associated with higher insulin levels(23.47 ± 15.94 μU/m L vs 15.8 ± 8.33 μU/m L, P = 0.027) and a higher frequency of insulin resistance(91.84% vs 72.22%, P = 0.02) compared with the lactase persistence phenotype. There were no associations between the LCT genotypes and diabetes(P = 0.651), dyslipidaemia(P = 0.328), hypertension(P = 0.507) or liver histology in these patients. Moreover, in the NASH patients, hypolactasia was an independent risk factor for insulin resistance even after adjusting for gender and age [OR = 5.0(95%CI: 1.35-20; P = 0.017)].CONCLUSION The LCT-13910 genotype distribution in Brazilian NAFLD patients was the same as that of the general population, but hypolactasia increased the risk of insulin resistance in the NASH patients.