Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038358 (gastric ulcer)
 5,179 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The activity of enzymes of the antioxidant system and pO2 in the gastric mucosa (GM) was studied in patients with gastric ulcer. The various enzymes differed in activity. Along with low activity of superoxide dismutase (SOD), glutathione peroxidase (GP), and glutathione reductase (GR), both normal and increased values were encountered. In GM hypoxia the GP activity increased in the peri-ulcerous zone. There was no statistically significant increase of SOD activity and reduction of GR activity.
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PMID:[Enzyme activity of the gastric mucosal antioxidant system during hypoxia]. 229 63

To clarify the role of glutathione (GSH), an antioxidative substance, and its association with the gastric mucosal defense mechanism, we examined the gastric mucosal GSH and GSH-dependent enzymes in gastric ulcer patients. The subjects of this study were 10 patients with active ulcer on the lesser curvature side in the lower part of the gastric body and 11 normal controls. At the time of gastric endoscopy, gastric mucosal specimens were obtained by routine forceps biopsy from a site several millimeters apart from the ulcer margin, and these specimens were used for measurement of GSH, glutathione peroxidase (GSH-Px), glutathione-S transferase (GST) and gamma-glutamyl transpeptidase (gamma-GTP). The GSH level and the GSH-Px and GST activities in the patients with gastric ulcer were lower than those in the control group. The GSH-Px activity at the healed stage after treatment was increased compared with the pre-treatment value, while the GSH level was not markedly increased and the GST and gamma-GTP activities were similar to the pre-treatment value. The GSH level and GSH-Px activity remained decreased in the non-responder group. These results suggest that gastric mucosal GSH and GSH-dependent enzymes are closely related to the etiology and course of gastric ulcer.
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PMID:Changes in glutathione in gastric mucosa of gastric ulcer patients. 767 Aug 48

Usnea longissima, a medicinal lichen of Anatolia (Turkey), is used in the treatment of gastric ulcer in local folk medicine. In this paper, the gastroprotective effect of usnic acid (UA) isolated from Usnea longissima was investigated in the indomethacin-induced gastric ulcers in rats at doses of 25, 50, 100 and 200 mg/kg body weight. The gastric lesions were significantly reduced by all doses of UA as compared with the indomethacin (25 mg/kg body weight) treated group. In the stomach tissues of treated animals, the in vivo antioxidant levels were evaluated. The administration of indomethacin caused a significant decrease in the levels of superoxide dismutase (SOD), glutathione peroxidase (GPx) and reduced glutathione (GSH), and an increase in the lipid peroxidation (LPO) level (p < 0.05). The administration of all doses of UA reversed the trend, inducing a significant increase of SOD, GSH and GPx levels and a reduction in LPO level in tissues. However, catalase (CAT), glutathione reductase (GR) and myeloperoxidase (MPx) activities, increased by indomethacin, were found to be lower in the UA- and ranitidine-treated groups. The gastric mucosal constitutive NO synthase (cNOS) and inducible NO synthase (iNOS) activities were also investigated in tissues of UA- (100 mg/kg), ranitidine- (50 mg/kg) and indomethacin-treated rat groups. The administration of UA and ranitidine increased the cNOS activity and lowered the iNOS activity as compared with indomethacin-treated group. These results suggest that the gastroprotective effect of UA can be attributed to its reducing effect on the oxidative damage and neutrophil infiltration in tissues.
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PMID:Gastroprotective and antioxidant effects of usnic acid on indomethacin-induced gastric ulcer in rats. 1616 75

Mucosal inflammation is a crucial factor for the recurrence of peptic ulcer. In this study, we examined the effect of rebamipide on neutrophils infiltration, lipid peroxidation, and antioxidative enzyme activities in the recurrence of experimental gastric ulcer. Ulcer recurrence was examined at 60, 100, and 140 days after production of acetic acid-induced gastric ulcers in rats. Gastric neutrophil infiltration, lipid peroxidation, and antioxidative enzyme activities were determined by analyses of myeloperoxidase (MPO) activity, thiobarbituric acid reactive substance (TBARS) levels, and glutathione peroxidase (GSHpx) and superoxide dismutase (SOD) activities in the ulcer region, respectively. The effect of rebamipide, an antigastric-ulcer agent, on ulcer recurrence was assessed following oral administration at 60 mg/kg/day from day 20. In the control and rebamipide groups, gastric ulcer indices were reduced on day 100 compared with day 60; however, increases were observed on day 140, indicating ulcer recurrence. In the rebamipide group, the ulcer index was smaller than in the control group at each time point and the effect was significant on day 140. Although marked elevation of MPO activities was observed in the control group during the experiment, no significant elevations were seen in the rebamipide group on days 100 and 140. TBARS levels were significantly elevated in the control group on day 140, but not in the rebamipide group. Rebamipide suppressed the decrease in GSHpx activity on day 60. These results suggest that lipid peroxidation of gastric tissue mediated by free radicals from neutrophils is responsible for the recurrence of acetic acid-induced gastric ulcers in rats, and that the elimination of free radicals by rebamipide may contribute to the reduction of severity in ulcer recurrence.
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PMID:Rebamipide reduces recurrence of experimental gastric ulcers: role of free radicals and neutrophils. 1618 27

It has been believed that overproduction of free radicals and/or deficiency of antioxidant systems, and stress hormones may play a role in etiopathogenesis of many diseases, including gastric ulcer. This study evaluated whether there was an effect of adrenalectomy on lipid peroxidation [malondialdehyde (MDA)] and antioxidant [superoxide dismutase (SOD), glutathione peroxidase (GPX) and glutathione (GSH) levels] systems in gastric tissue and erythrocyte in rats. As well, the impacts of administration of prednisolone and epinephrine on these systems in adrenalectomized rats were investigated. Thirty-three rats were randomly grouped as sham-operated (group I), adrenalectomized (group II), adrenalectomized + prednisolone (group III) and adrenalectomized + epinephrine (group IV). After experimental procedures, blood and gastric tissues samples were taken from each animal in all groups. Colorimetric assays were employed to determine gastric tissue and erythrocyte levels of MDA and GSH, and SOD and GPX activities. Adrenalectomy in group II rats caused a marked decrease of SOD and GPX activities and MDA levels, and an increase of GSH levels in gastric tissue and erythrocyte, when compared to sham-operated rats. However, especially epinephrine injection after adrenalectomy resulted in a significantly increase of measured antioxidant enzyme activities and GSH levels in both gastric tissue and erythrocyte. These results indicate that adrenalectomy appeared to alter the levels of antioxidants and lipid peroxidation product in gastric tissue and erythrocyte. Thus, the present study provides a physiological regulatory role of adrenal gland in the maintenance of oxidant/antioxidant balance in gastric tissue and erythrocyte.
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PMID:The role of prednisolone and epinephrine on gastric tissue and erythrocyte antioxidant status in adrenalectomized rats. 1744 Feb 30

This research was performed in order to determine the potential protective effects of ozonized sunflower oil (OSO) in the injury of rat gastric mucosa induced by absolute ethanol and as well as to elucidate the role of reactive oxygen species (ROS), lipid peroxidation, and some important constituents of antioxidant defense such as superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) in these effects. OSO was administered to rats intragastrically by a cannula and it was applied during four days to animals. The doses of OSO administered daily to each group of rats were 4, 12, and 24 mg/kg, respectively, and one hour after the last treatment, absolute ethanol (1 mL/200 mg body weight) was administered. Our results showed that gastric ulcer index was significantly reduced in rats pretreated with OSO as compared with ethanol-treated controls. However, in rats pretreated with OSO, no significant reduction of TBARS content in gastric mucosa was found as compared to those rats treated with ethanol alone. In contrast, SOD and GSH-Px activities were significantly increased in gastric mucosa of OSO-pretreated rats with respect to those treated with ethanol alone. In summary, our results demonstrate that OSO pretreatment exerts protective effects in ethanol-induced gastric ulcers in rats. Furthermore, these results provide evidence that these protective effects of OSO are mediated at least partially by stimulation of some important antioxidant enzymes such as SOD and GSH-Px, which are scavengers of ROS and therefore prevent gastric injury induced by them.
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PMID:Antioxidant mechanism is involved in the gastroprotective effects of ozonized sunflower oil in ethanol-induced ulcers in rats. 1749 36

Guazuma ulmifolia Lam., a member of the Sterculiaceae family, is used in folk medicine because of its antioxidant, antimicrobial and antihypertensive properties. Most of the research work carried out on this plant has focused on the bark because of its high concentration of antioxidant proanthocyanidins. The flowers and leaves of Guazuma ulmifolia, though less studied, are also used as a remedy for different conditions, such as kidney and gastrointestinal diseases, fever and diabetes. The aim of this study was to assess the gastroprotective effects of an aqueous suspension of the ethanolic extract from leaves and flowers of Guazuma ulmifolia in a model of acute gastric ulcer induced by diclofenac as ulcerogenic agent, using the proton pump inhibitor omeprazole as a protection reference. Therefore, the extract was administered two times orally to three groups of Wistar rats at doses of 500, 250 and 125mg/kg, with a 24-h interval between doses. Diclofenac (100mg/kg) was given 1h after the last administration of the extract. Pretreatment with Guazuma ulmifolia or omeprazole decreased the ulcerated area in a dose-dependent way. Myeloperoxidase activity as a marker of neutrophil infiltration was slightly reduced in vivo, whereas in vitro, anti-inflammatory activity was clearly inhibited in a dose-dependent way. The lowest doses of the extract significantly decreased the levels of lipoperoxides, and superoxide dismuthase activity increased to a similar extent as with omeprazole (P<0.001). Examination of glutathione metabolism reflected a significant rise in glutathione peroxidase activity at the highest dose of Guazuma ulmifolia. Finally, there was a faint elevation in prostaglandin E(2) levels with all doses, though the depletion induced by diclofenac could not be reverted. We conclude that the aerial parts of Guazuma ulmifolia protect gastric mucosa against the injurious effect of NSAIDs mainly by anti-inflammatory and radical-scavenging mechanisms.
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PMID:The aerial parts of Guazuma ulmifolia Lam. protect against NSAID-induced gastric lesions. 1788 15

Ethanol-induced oxidative damage is commonly associated with the generation of reactive oxygen molecules, leading to oxidative stress. Considering that antioxidant activity is an important mechanism of action involved in cytoprotection, the aim of this work was to evaluate the antioxidant properties of the alkaloid indigo (1) (2 mg/kg, P. O.), obtained from the leaves of Indigofera truxillensis Kunth (Fabaceae), on rat gastric mucosa submitted to ethanol-induced (100%, 1 mL, P. O.) gastric ulcer. Enzymatic assays and DNA fragmentation analysis were performed. When ethanol was administered to the control group, the sulfhydryl content (SH) and the glutathione peroxidase (GPx) activity decreased by 41% and 50%, respectively; in contrast, superoxide dismutase (SOD) and glutathione reductase (GR) activities increased by 56% and 67%, respectively. Additionally, myeloperoxidase (MPO) activity, a marker for free radical generation caused by polymorphonuclear neutrophil (PMN) tissue infiltration, also increased 4.5-fold after ethanol treatment. Rat gastric mucosa exposed to ethanol showed DNA fragmentation. Indigo alkaloid pretreatment protected rats from ethanol-induced gastric lesions. This effect was determined by the ulcerative lesion area (ULA), indicating an inhibition of around 80% at 2 mg/kg. This alkaloid also diminished GPx activity, which was higher than that observed with ethanol alone. However, this effect was counterbalanced by increased GR activity. Indigo was unable to restore alterations in SOD activity promoted by ethanol. After indigo pretreatment, SH levels and MPO activity remained normal and gastric mucosa DNA damage caused by ethanol was also partially prevented by indigo. These results suggest that the gastroprotective mechanisms of indigo include non-enzymatic antioxidant effects and the inhibition of PMN infiltration which, in combination, partially protect the gastric mucosa against ethanol-induced DNA damage.
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PMID:Antioxidant activity of indigo and its preventive effect against ethanol-induced DNA damage in rat gastric mucosa. 1797 1

This study investigated the involvement of neutrophil infiltration, disturbances in nitric oxide (NO) generation and oxidative stress in indomethacin-induced gastric ulcer, and the possible gastroprotective potentials of leptin, known for its angiogenic effect. Male Wistar albino rats (180-220 g) were allocated into a normal control group, ulcer control group (received a single dose of indomethacin 40 mg/kg p.o.) and an ulcer group pretreated with leptin (10 microg/kg i.p. 30 min before ulcer induction). The animals were killed 6 h after indomethacin administration and their gastric juice, serum and mucosal tissue were used for gastric injury evaluation. Indomethacin produced multiple lesions in glandular mucosa, evidenced by marked increase in gastric ulcer index (GUI) accompanied by significant increases in gastric juice acidity, tissue myeloperoxidase (MPO) activity, serum NO and tissue conjugated diene (CD), and marked decreases in tissue NO and glutathione (GSH) as well as glutathione reductase (GR) and superoxide dismutase (SOD) activities, while gastric juice mucin and tissue glutathione peroxidase (GPx) were not affected. Leptin exerted significant gastroprotection as evidenced by significantly decreased GUI and attenuated neutrophil infiltration. Leptin significantly increased mucin and tissue NO, restored GR and SOD activities and up-regulated GPx activity. It failed to affect acidity, serum NO, GSH and CD. These results suggest that leptin confers significant gastroprotection against indomethacin-induced injury through interfering with neutrophil infiltration, NO production and oxidative stress.
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PMID:Gastroprotective effect of leptin in indomethacin-induced gastric injury. 1818 Oct 30

Nicotinamide, a precursor of nicotinamide adenine dinucleotide (NAD(+)), is an essential nutrient for cell growth that participates in DNA repair and energy production. Nonsteroidal anti-inflammatory drugs (NSAIDs)-induced gastropathy is an intricate process involving gastric mucus depletion, increased microvascular permeability, nitric oxide imbalance, as well as free radical production. The present study was conducted to test for the possible gastroprotective effect of nicotinamide utilizing an acute indomethacin-induced gastric ulcer model. Sucralfate possesses antiulcer/antioxidant properties; hence it was used as the reference drug. Indomethacin resulted in hemorrhagic mucosal lesions, increased microvascular permeability, and reduced the gastric mucosal contents of nitric oxide and mucus. Moreover, it produced an imbalance in the mucosal redox state as indicated by a decline of glutathione and glutathione peroxidase, which were associated with increased lipid peroxides. Comparable to sucralfate, nicotinamide markedly decreased the severity of indomethacin-induced gastric lesions and restored the levels of altered biochemical parameters. Gastroprotection afforded by nicotinamide is possibly mediated by conservation of gastric mucus, as well as nitric oxide contents, enhanced gastric microvascular permeability, and its antioxidant properties.
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PMID:Nicotinamide alleviates indomethacin-induced gastric ulcers: a novel antiulcer agent. 1985 87


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