| 1 | Protective action of glutamine in rats with severe acute liver failure显示文摘BACKGROUND Severe acute liver failure(SALF) is a rare, but high-mortality, rapidly evolving syndrome that leads to hepatocyte degeneration with impaired liver function.Thioacetamide(TAA) is a known xenobiotic, which promotes the increase of the formation of reactive oxygen species. Erythroid 2-related factor 2(Nrf2) activates the antioxidant protection of cells. Studies have evidenced the involvement of inflammatory mediators in conditions of oxidative stress.AIM To evaluate the antioxidant effects of glutamine on Nrf2 activation and NFκBmediated inflammation in rats with TAA-induced IHAG.METHODS Male Wistar rats(n = 28) were divided into four groups: control,control+glutamine, TAA, and TAA + glutamine. Two TAA doses(400 mg/kg)were administered intraperitoneally, 8 h apart. Glutamine(25 mg/kg) was administered at 30 min, 24 h, and 36 h. At 48 h, blood was collected for liver integrity analysis [aspartate aminotransferase(AST), alanine aminotransferase(ALT), and alkaline phosphatase(ALP)]. The liver was harvested for histology and assessment of oxidative stress [thiobarbituric acid-reactive substances(TBARS), catalase(CAT), glutathione peroxidase(GPx), glutathione S-transferase(GST), glutathione(GSH), Nrf2, Kelch-like ECH-associated protein 1(Keap1),NADPH quinone oxidoreductase1(NQO1), superoxide dismutase(SOD)] and inflammatory process.RESULTS TAA caused disruption of the hepatic parenchyma, with inflammatoryinfiltration, massive necrosis, and ballooning degeneration. Glutamine mitigated this tissue damage, with visible regeneration of hepatic parenchyma; decreased TBARS(P < 0.001), GSH(P < 0.01), IL-1β, IL6, and TNFα levels(P <0.01) in hepatic tissue; and decreased blood levels of AST, ALT, and ALP(P <0.05). In addition, CAT, GPx, and GST activities were restored in the glutamine group(P<0.01, P <0.01, and P <0.001, respectively vs TAA alone). Glutamine increased expression of Nrf2(P < 0.05), NQO1, and SOD(P < 0.01), as well as levels of IL-10(P <0.001), while decreasing expression of Keap1, TLR4, NFκB(P < 0.001), COX-2 and iNOS,(P < 0.01), and reducing NO_2 and NO_3 levels(P < 0.05).CONCLUSION In the TAA experimental model of IHAG, glutamine activated the Nrf2 pathway,thus promoting antioxidant protection, and blunted the NFκB-mediated pathway, reducing inflammation. | Elizangela G Schemitt Renata M Hartmann Josieli R Colares Francielli Licks Jéferson O Salvi Cláudio A Marroni Norma P Marroni | 2019 | World Journal of Hepatology2019,11,3: | 5 |
| 4 | Melatonin prevents oxidative stress,inflammatory activity,and DNA damage in cirrhotic rats显示文摘BACKGROUND Cirrhosis is an important health problem characterized by a significant change in liver parenchyma.In animals,this can be reproduced by an experimental model of bile duct ligation(BDL).Melatonin(MLT)is a physiological hormone synthesized from serotonin that has been studied for its beneficial properties,including its antioxidant potential.AIM To evaluate MLT’s effects on oxidative stress,the inflammatory process,and DNA damage in an experimental model of secondary biliary cirrhosis.METHODS Male Wistar rats were divided into 4 groups:Control(CO),CO+MLT,BDL,and BDL+MLT.MLT was administered(20 mg/kg)daily beginning on day 15 after biliary obstruction.On day 29 the animals were killed.Blood samples,liver tissue,and bone marrow were collected for further analysis.RESULTS BDL caused changes in biochemical and histological parameters and markers of inflammatory process.Thiobarbituric acid(0.46±0.01)reactive substance levels,superoxide dismutase activity(2.30±0.07)and nitric oxide levels(2.48±0.36)were significantly lower(P<0.001)n the groups that received MLT.DNA damage was also lower(P<0.001)in MLT-treated groups(171.6±32.9)than the BDL-only group(295.5±34.8).Tissue damage and the expression of nuclear factor kappa B,interleukin-1β,Nrf2,NQO1 and Hsp70 were significantly lower in animals treated with MLT(P<0.001).CONCLUSION When administered to rats with BDL-induced secondary biliary cirrhosis,MLT effectively restored the evaluated parameters. | Josieli R Colares Renata M Hartmann Elizângela G Schemitt Sandielly R B Fonseca Marilda S Brasil Jaqueline N Picada Alexandre S Dias Aline F Bueno Cláudio A Marroni Norma P Marroni | 2022 | World Journal of Gastroenterology2022,28,3: | 1 |