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The extract of B. serrata has active antioxidant substances that exert protective effects in acute experimental colitis.

AIMTo evaluate the effects of melatonin (Mel) on oxidative stress in an experimental model of bile duct ligation (BDL).METHODSMale Wistar rats (n = 32, weight ± 300 g) were allocated across four groups: CO (sham BDL), BDL (BDL surgery), CO + Mel (sham BDL and Mel administration) and BDL + Mel (BDL surgery and Mel administration). Mel was administered intraperitoneally for 2 wk, starting on postoperative day 15, at a dose of 20 mg/kg.RESULTSMel was effective at the different standards, reestablishing normal liver enzyme levels, reducing the hepatosomatic and splenosomatic indices, restoring lipoperoxidation and antioxidant enzyme concentrations, reducing fibrosis and inflammation, and thereby reducing liver tissue injury in the treated animals.CONCLUSIONThe results of this study suggest a protective effect of Mel when administered to rats with secondary biliary cirrhosis induced by BDL.

Ulcerative colitis is an inflammatory disease that involves only the colon and rectum, being characterized by leukocyte infiltrate and superficial ulcers in the intestinal mucosa. To evaluate the anti-inflammatory and antioxidant effects of extract from the Boswellia serrata plant in an experimental rat model of acute ulcerative colitis induced by the administration of acetic acid (AA). An extract of B. serrata (34.2 mg/kg/day) was administered by oral gavage for 2 days before and after the induction of colitis with 4 mL of 4% AA. The anal sphincter pressure in the colitis group showed a significant decrease compared to that of the control groups (p < 0.001). The analysis of the values of lipid peroxidation (LPO) obtained by substances that react with thiobarbituric acid (TBARS) showed a significantly increased LPO in the colitis group compared to the control groups (p < 0.001). The nitric oxide levels and the expression of inducible nitric oxide synthase (iNOS) showed a significant increase in the colitis group compared to control groups (p < 0.01). Both pretreatment and treatment with B. serrata exhibited significantly reduced lipid peroxidation, nitric oxide and iNOS and showed improvements in tissue injury and anal sphincter pressure in animals with ulcerative colitis. The B. serrata extract has protective anti-inflammatory and antioxidant effects that inhibit inflammatory mediators in acute experimental colitis.

Intestinal ischemia and reperfusion (I/R) causes cellular and tissue damage to the intestine and remote organs such as the liver. Increased production of ROS and nitric oxide and dysregulation of cytoprotective enzymes may be involved in intestinal I/R. The aim was to evaluate the protective effects of glutamine on the intestine and liver of rats with intestinal I/R injury. Twenty male Wistar rats (300 g) were divided into four groups: sham-operated (SO), glutamine + SO (G + SO), I/R, and glutamine + I/R (G + I/R). Occlusion of the SMA for 30 min was followed by 15-min reperfusion. Glutamine (25 mg/kg/day) was administered once daily 24 and 48 h before I/R induction. Blood and tissue of were collected for aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, histopathological analysis, immunohistochemistry of IL-1β and TNF-α, thiobarbituric acid reactive substance (TBARS) and nitric oxide, Nrf2/keap1, superoxide dismutase (SOD), NADPH quinone oxidoreductase1 (NQO1), inducible nitric oxide synthase (iNOS), heat shock protein (HSP70), glucose-regulated protein 78 (GRP78), and activating transcription factor 6 (ATF-6) by western blot. Statistic analysis by ANOVA-Student-Newman-Keuls test (mean ± SE) significantly was p < 0.05. Tissue damage, AST, ALT, IL-1β, TNF-α, TBARS, NO, Keap1, iNOS, GRP78, and ATF-6 expression were significantly lower in the G + I/R group as compared to the I/R group. Expression of Nrf2, SOD, NQO1, and HSP70, was significantly higher in the G + I/R group as compared to I/R group. Pre-treatment with glutamine provided protection against oxidative damage in the intestine and liver in an experimental model of intestinal I/R.

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 NFκB-mediated 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 inflammatory infiltration, 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.

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Ulcerative colitis (UC) is an inflammatory disease that affects the bowels. Reactive oxygen species (ROS) are involved in the progress of UC. Objective Evaluate the antioxidant effect of lecithin in an experimental model of acute UC induced by administration of acetic acid (AA) in rats. Methods Lecithin (0.5 mL/kg/day) administered orally 2 days before and after induction of colitis with 4% AA in a volume of 4 mL. Twenty-five male Wistar rats were divided in 5 groups: control (CO); control + lecithin (CO + LE); colitis (CL); colitis + lecithin (CL + LE); lecithin + colitis (LE + CL). Anal sphincter pressure, LPO (TBARS), and antioxidant activity of enzymes superoxide dismutase (SOD) and catalase (CAT) were measured, and a histological analysis with H&E was performed. Results and discussion Anal sphincter pressure was significantly smaller in the CO group, lecithin treatment increased it in pre- and post-treated groups. LPO and SOD activity were increased in the CO group and decreased in the lecithin-treated groups. CAT activity was increased in CO group and decreased in lecithin groups. The histological analysis showed damage to the bowels with destruction of crypts, edema, and inflammatory infiltrate. Use of lecithin preserved the crypts and decreased the edema. Conclusion Ulcerative colitis increased lipid peroxidation, and the use of lecithin was effective reducing damage to the bowels in the model of experimental colitis.