Effects of Fasting and Glutathione Depletors on the GSH-Dependent Enzyme System in the Gastrointestinal Mucosa ofthe Rat

Siegers, C.‐P.; Bartels, Lars Erik; Riemann, Dieter

doi:10.1159/000138529

Cited by 20 publications

(8 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Addressing the regional differences in antioxidant enzymes’ activities in the rat intestine, Moghadasian and Godin (1996) reported that while glutathione levels were significantly higher in the mucosa of the rat small intestine compared to the mucosa of the colon, no differences were found in the levels of GPx and SOD of these segments [ 61 , 62 ]. In contrast, Siegers and coworkers found a gradual decrease in the activity of GPx from the proximal small intestine of the rat towards the colon [ 63 ]. Pig fed GP+ diet produced a higher activity of the three antioxidant enzymes in duodenum, which was significant for SOD.…”

Section: Discussionmentioning

confidence: 99%

Intestinal Absorption and Antioxidant Activity of Grape Pomace Polyphenols

et al. 2018

View full text Add to dashboard Cite

The absorption and antioxidant activity of polyphenols from grape pomace (GP) are important aspects of its valorization as a feed additive in the diet of weaned piglets. This study aimed to evaluate the presence of polyphenols from GP both in vitro in IPEC cells and in vivo in the duodenum and colon of piglets fed with diets containing or not 5% GP and also to compare and correlate the aspects of their in vitro and in vivo absorption. Total polyphenolic content (TPC) and antioxidant status (TAS, CAT, SOD and GPx enzyme activity, and lipid peroxidation-TBARS level) were assessed in duodenum and colon of piglets fed or not a diet with 5% GP. The results of UV-Vis spectroscopy demonstrated that in cellular and extracellular medium the GP polyphenols were oxidized (between λmax = 276 nm and λmax = 627.0 nm) with the formation of o-quinones and dimers. LC-MS analysis indicated a procyanidin trimer possibly C2, and a procyanidin dimer as the major polyphenols identified in GP, 12.8% of the procyanidin trimer and 23% of the procyanidin dimer respectively being also found in the compound feed. Procyanidin trimer C2 is the compound accumulated in duodenum, 73% of it being found in the colon of control piglets, and 62.5% in the colon of GP piglets. Correlations exist between the in vitro and in vivo investigations regarding the qualitative evaluation of GP polyphenols in the cells (λmax at 287.1 nm) and in the gut (λmax at 287.5 nm), as oxidated metabolic products. Beside the presence of polyphenols metabolites this study shows also the presence of the unmetabolized procyanidin trimers in duodenum and colon tissue, an important point in evaluating the benefic actions of these molecules at intestinal level. Moreover the in vivo study shows that a 5% GP in piglet’s diet increased the total antioxidant status (TAS) and decreased lipid peroxidantion (TBARS) in both duodenum and colon, and increased SOD activity in duodenum and CAT and GPx activity in colon. These parameters are modulated by the different polyphenols absorbed, mainly by the procyanidin trimers and catechin on one side and the polyphenols metabolites on the other side.

show abstract

Section: Discussionmentioning

confidence: 99%

Intestinal Absorption and Antioxidant Activity of Grape Pomace Polyphenols

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Sulphyldryl compounds have been shown to protect the gastric mucosa from ethanol‐induced damage both in animals and man (Szelenyi & Brune, 1988; Loguercio et al , 1993). GSH is a major endogenous antioxidant in the organism and it is present in high concentrations in the stomach and bowel of both rodents and man (Boyd et al , 1979; Hoppenkamps et al , 1984; Siegers et al , 1984; 1989). The reduction in tGSH concentration elicited by ethanol in the present study deprives the cell of one of its most important antioxidants and impairs the balance between GSSG and GSH concentrations.…”

Section: Discussionmentioning

confidence: 99%

Suppressive effect of melatonin administration on ethanol‐induced gastroduodenal injury in rats in vivo

Melchiorri

Sewerynek

Reíter

et al. 1997

British J Pharmacology

View full text Add to dashboard Cite

1. Melatonin protection against ethanol-induced gastroduodenal injury was investigated in duodenumligated rats. 2. Melatonin, injected i.p. 30 min before administration of 1 ml of absolute ethanol, given by gavage, significantly decreased ethanol-induced macroscopic, histological and biochemical changes in the gastroduodenal mucosa. 3. Ethanol-induced lesions were detectable as haemorrhagic streaks. Ethanol administration damaged 36% and 25% of the total gastric and duodenal surface, respectively. Melatonin treatment reduced ethanol-induced gastric and duodenal damage to 14% and 8%, respectively. When indomethacin was given together with ethanol, the gastric damaged area was 44% of the total surface, while the duodenal damaged area was 35%; melatonin administration reduced the damage to only 13% of the total gastric surface and to 12% of total duodenal surface. 4. Both stomach and duodenum of ethanol-treated animals showed polymorphonuclear leukocyte (PMN) infiltration. The number of PMN increased more than 600 and 200 times in stomach and duodenum, respectively, following ethanol administration. Melatonin treatment reduced ethanol-induced PMN infiltration by 38% in the stomach and 20% in the duodenum. In indomethacin-ethanol-treated rats, the number of PMN increased by 875% compared to control group in the stomach and by 264% in duodenum. Melatonin administration reduced the indomethacin-ethanol-induced PMN rise by 57% in the stomach and 40% in the duodenum. 5. Gastroduodenal total glutathione (tGSH) concentration and glutathione reductase (GSSG-Rd) activity were significantly reduced following ethanol and indomethacin-ethanol administration. Melatonin ameliorated both the decrease in tGSH concentration as well as the reduction of GSSG-Rd activity elicited by ethanol both in the stomach and duodenum; melatonin was effective against indomethacin-ethanol-induced damage only in the stomach. 6. Ethanol-induced gastroduodenal damage is believed to be mediated by the generation of free radicals. Recently, a number of in vivo and in vitro experiments have shown melatonin to be an effective antioxidant and free radical scavenger; thus, we conclude that the protection by melatonin against ethanol-induced gastroduodenal injury is due, at least in part, to its radical scavenging activity.

show abstract

“…Glutathione is also involved in normal mucosal defense mechanisms. Its levels are high in the Gl system Siegers et al, 1989), and BSO treatment in vivo damages the Gl tract (Martensson et al, 1990;Hirota et al, 1989) and sensitizes it toward the development of hemorrhage (Stein et al, 1990). The effectiveness of mercury as a Gl toxin might be related to its ability to sequester glutathione, but this would not satisfactorily explain why copper salts, which also appear to bind glutathione physiologically in vitro, are much less toxic orally (LD50s between 200 and 1000 mg/kg; NIOSH, 1976).…”

Section: Discussionmentioning

confidence: 99%

Cytotoxicity of heavy metals in the human small intestinal epithelial cell line I‐407: The role of glutathione

Keogh

Steffen

Siegers

1994

Journal of Toxicology and Environmental Health

View full text Add to dashboard Cite

Cytotoxicities of metal salts were determined in the intestinal epithelial cell line I-407 in microwell culture plates over 48 h using the widely utilized and accepted neutral red uptake procedure. Rank order cytotoxicities induced by the metal salts (in terms of LC50 values) were found to be HgCl2 (32 microM) > CdCl2 (53 microM) > CuCl2 (156 microM) > T12SO4 (377 microM) > Pb(NO3)2 (1.99 mM). Combined administration of the two most toxic metals at their LC50's showed that their toxicities were not additive or synergistic. The role of glutathione in determining toxicity induced by the metal salts in these cells was assessed by inhibition of its synthesis. Buthionine sulfoximine pretreatment at 1 mM, which was not toxic to the cells, caused sustained reduction in cellular glutathione content (to 13.8% after 48 h) and increased toxicities induced by HgCl2 (5.7-fold) and CuCl2 (1.44-fold) as shown by reductions in the LC50 values. Toxicity induced by the other metals remained unaffected. Administration of glutathione with either HgCl2 or CdCl2 did not protect the cells against their toxicity, and in the case of cadmium its toxicity was exacerbated. N-Acetylcysteine diminished toxicity induced by mercury but not cadmium.

show abstract

Effects of Fasting and Glutathione Depletors on the GSH-Dependent Enzyme System in the Gastrointestinal Mucosa ofthe Rat

Cited by 20 publications

References 11 publications

Intestinal Absorption and Antioxidant Activity of Grape Pomace Polyphenols

Intestinal Absorption and Antioxidant Activity of Grape Pomace Polyphenols

Suppressive effect of melatonin administration on ethanol‐induced gastroduodenal injury in rats in vivo

Cytotoxicity of heavy metals in the human small intestinal epithelial cell line I‐407: The role of glutathione

Contact Info

Product

Resources

About