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 precise role of insulin-like growth factor (IGF)-1 in gastric ulcer healing is unknown. In experimental rat gastric ulcers, we examined expression of IGF-1 mRNA and protein by reverse transcriptase-polymerase chain reaction or enzyme-linked immunosorbent assay and immunostaining, respectively. In cultured rat gastric epithelial RGM1 cells, we examined effects of exogenous IGF-1 on cell migration, re-epithelialization, and proliferation-essential components of ulcer healing. We also examined whether IGF-1 induces cyclooxygenase (COX)-2 expression and determined the role of phosphatidylinositol 3-kinase and mitogen-activated protein kinase signaling pathways in mediating IGF-1 actions. Gastric ulceration triggered an approximately threefold increase in IGF-1 expression in epithelial cells of the ulcer margins (P < 0.001 versus control), especially in cells re-epithelizing granulation tissue and in mucosa in proximity to the ulcer margin. Treatment of RGM1 cells with IGF-1 caused a dramatic increase in actin polymerization, an eightfold increase in cell migration (P < 0.001), a 195% increase in cell proliferation (P < 0.05), and a sixfold increase in COX-2 expression (P < 0.01). Inhibitor of phosphatidylinositol 3-kinase abolished IGF-1-induced RGM1 cell migration and proliferation, actin polymerization, and COX-2 expression. The up-regulation of IGF-1 in gastric ulcer margin accelerates gastric ulcer healing by promoting cell re-epithelization, proliferation, and COX-2 expression via the phosphatidylinositol 3-kinase pathway.
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PMID:Novel roles of local insulin-like growth factor-1 activation in gastric ulcer healing: promotes actin polymerization, cell proliferation, re-epithelialization, and induces cyclooxygenase-2 in a phosphatidylinositol 3-kinase-dependent manner. 1739 62

We examined the involvement of cyclooxygenase (COX)-1 as well as COX-2 in the healing of gastric ulcers and investigated which prostaglandin (PG) EP receptor subtype is responsible for the healing-promoting action of PGE2. Male SD rats and C57BL/6 mice, including wild-type, COX-1(-/-), and COX-2(-/-), were used. Gastric ulcers were produced by thermocauterization under ether anesthesia. Gastric ulcer healing was significantly delayed in both rats and mice by indomethacin and rofecoxib but not SC-560 given for 14 days after ulceration. The impaired healing was also observed in COX-2(-/-) but not COX-1(-/-) mice. Mucosal PGE2 content increased after ulceration, and this response was significantly suppressed by indomethacin and rofecoxib but not SC-560. The delayed healing in mice caused by indomethacin was significantly reversed by the coadministration of 11-deoxy-PGE1 (EP3/EP4 agonist) but not other prostanoids, including the EP1, EP2, and EP3 agonists. By contrast, CJ-42794 (selective EP(4) antagonist) significantly delayed the ulcer healing in rats and mice. VEGF expression and angiogenesis were both upregulated in the ulcerated mucosa, and these responses were suppressed by indomethacin, rofocoxib, and CJ-42794. The expression of VEGF in primary rat gastric fibroblasts was increased by PGE2 or AE1-329 (EP4 agonist), and these responses were both attenuated by coadministration of CJ-42794. These results confirmed the importance of COX-2/PGE2 in the healing mechanism of gastric ulcers and further suggested that the healing-promoting action of PGE2 is mediated by the activation of EP4 receptors and is associated with VEGF expression.
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PMID:Cyclooxygenase-2/prostaglandin E2 accelerates the healing of gastric ulcers via EP4 receptors. 1767 47

Non-steroidal anti-inflammatory drug (NSAID) has been widely prescribed as a useful antifebrile or painkiller. But, gastrointestinal injury as a side effect of NSAIDs has been a big social probrem. NSAID-induced gastric damage has been shown to be induced by the inhibition of both cyclooxygenase (COX)-1 and 2. Thus, selective COX-2 inhibitors are expected to induce less gastric injury and to be safe as compared to traditional NSAIDs. But in certain situations such as gastric ulcer or H. pylori-induced gastritis, selective COX-2 inhibitors may delay ulcer healing or repair processes. Previous reports have shown that COX-2 inhibitors increase cardiovascular (CV) events as compared with placebo and recent studies further suggest that all NSAIDs might also be involved in increases in CV events. Therefore, any NSAIDs must be carefully used when they are prescribed for patients with CV risks.
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PMID:[The choice of selective COX-2 inhibitors]. 1792 30

NSAIDs compromise gastroduodenal defense mechanism mediated by inhibiting cyclooxygenase and leading to leukocyte infiltration or neutrophil adherence, and cause gastric ulcers. There are a number of mucoprotective drugs in Japan, and they were often used for NSAIDs-induced ulcer treatment. In vitro or in vivo studies, some mucoprotective drugs have been shown to have anti-inflammatory action due to the inhibition of leukocyte infiltration, production of inflammatory cytokines. However, mucoprotective drugs were given a low priority in "the Japanese guideline for the management of gastric ulcer" edited in 2003. Therefore, mucoprotective drugs should be investigated in terms of effects on NSAIDs-induced gastric ulcer patients because there are a few reliable evidences for the treatment of NSAID-induced gastric ulcer in Japan.
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PMID:[The role of mucoprotective drugs in a treatment and prevention for NSAID-induced gastric ulcer]. 1792 35

Celecoxib is a frequently used nonsteroidal anti-inflammatory drug (NSAID) in the treatment of rheumatoid arthritis and osteoarthritis. It selectively inhibits cyclooxygenase II (COX-2) enzyme which is responsible for the production of proinflammatory prostanoids. It has been proposed that since it does not significantly inhibit COX-1, an isoenzyme responsible for the production of cytoprotective prostanoids, celecoxib has fewer side effects in the stomach. Dipyrone which is a drug with potent analgesic activity has no significant inhibitory effect on COX. In this study, the effects of celecoxib and dipyrone on experimentally induced gastric ulcers in rats were compared with respect to different parameters. In the first experiment, in an attempt to identify the best dose for both drugs, a histamine-induced gastric ulcer model was used and each drug was administered at 5, 25 and 100 mg/kg doses, and ulcer index, acidity and mucus secretion were measured in the stomach. The best dose was determined to be 5 mg/kg for both drugs. Celecoxib was found to delay ulcer healing when compared to dipyrone especially when ulcer index was used as measure. In the second experiment, ulcer index, acidity, mucus secretion, and the levels of myeloperoxidase (MPO), lipid peroxide (MDA), non-protein sulfhydryl groups (NP-SH), and prostaglandin E2 (PGE2) were investigated in the stomach of rats with gastric ulcers induced by histamine, stress and diethyldithiocarbamate (DDC). While celecoxib increased the ulcer index in stress-induced ulcer, dipyrone decreased the index in DDC-induced ulcer. Celecoxib also caused a significant increase of gastric mucus secretion in histamine-induced ulcer model. Gastric lipid peroxidation was significantly increased by dipyrone in the control group without gastric ulcer induction, whereas it was significantly increased by celecoxib in the histamine-induced and stress-induced ulcer groups. Dipyrone promoted a decrease in gastric NP-SH levels in the control group with stress-induced ulcer. With respect to gastric MPO activity, dipyrone caused a decrease in the histamine-induced ulcer group but it caused an increase in the stress-induced and DDC-induced ulcer groups. Gastric PGE2 levels in the control group without gastric ulcer induction were not affected by celecoxib while they were increased by dipyrone. In conclusion, celecoxib prompted the formation of experimentally induced gastric ulcers more than did dipyrone. The study was supported by Osmangazi University Research Funds.
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PMID:The effects of some nonsteroidal anti-inflammatory drugs on experimental induced gastric ulcers in rats. 1823 17

We examined the protective effects of sesamol against acute gastric mucosal damage induced in rats by nonsteroidal anti-inflammatory drug diclofenac (DLF). We also measured the ulcer index, nitrite, iNOS, lipid peroxidation, hydroxyl radical, superoxide anion, reduced glutathione levels, prostaglandin E2, mucus, and cyclooxygenase activity in the rat mucosa. Sesamol attenuated gastric ulcer, nitrite, and iNOS in DLF-treated stomachs. Sesamol reduced mucosal lipid peroxidation and hydroxyl radical levels; however, neither DLF nor sesamol affected mucosal superoxide anion production. In addition, sesamol significantly maintained the reduced mucosal glutathione levels in DLF-treated stomachs of rats. Sesamol did not affect mucosal mucus production, but it further decreased DLF-induced mucosal prostaglandin E2 generation and cyclooxygenase activity. Therefore, sesamol might protect gastric mucosa against DLF-induced injury by inhibiting hydroxyl radical-associated lipid peroxidation. In addition, the cyclooxygenase pathway may not be involved in sesamol's gastric mucosal protection.
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PMID:Sesamol attenuates diclofenac-induced acute gastric mucosal injury via its cyclooxygenase-independent antioxidative effect in rats. 1827 48

Basic fibroblast growth factor (bFGF) is essential for gastric ulcer healing, whereas glucocorticoids delay gastric ulcer healing. We found that dexamethasone inhibited bFGF-stimulated rat gastric epithelial RGM-1 cells proliferation and attempted to elucidate the possible mechanistic pathway. Flowcytometry was used to determine cell proliferation. Western blot and RT-PCR were performed to evaluate changes in signaling pathways. Results showed that bFGF significantly increased mRNA expression of FGF receptor (FGFR)1 and FGFR2 at 10 min and increased expression of phosphorylated extracellular signal-regulated kinase (pERK1/pERK2) but not phosphorylated p38 mitogen-activated protein kinase (MAPK) or phosphorylated phosphatidylinositol 3-kinase (PI3K) within 30 min. This was followed by an increase of cyclooxygenase (COX)-2 mRNA and protein expression at 30 and 240 min, respectively. Mitogen-activated protein kinase kinase (MEK) inhibitor-PD98059 (10(-5) M) markedly suppressed bFGF-stimulated COX-2 expression and cell proliferation, but neither p38 MAPK inhibitor-SB203580 nor PI3K inhibitor-Wortmannin had any effect. Dexamethasone (10(-6)M) substantially reduced bFGF-stimulated ERK activation at 10 min, COX-2 mRNA and protein expression at 30 and 240 min, respectively, and prostaglandin E(2) synthesis at 8 h. Dexamethasone (10(-6) M) also significantly decreased mRNA expression of FGFR1 and FGFR2 at basal and bFGF-stimulated conditions at 10 min. This study indicated that bFGF-stimulated gastric epithelial RGM-1 cells proliferation via up-regulating FGFR1 and FGFR2, activating ERK1/ERK2 signal transduction pathway and COX-2 pathway. Dexamethasone significantly suppresses bFGF-stimulated RGM-1 cells proliferation in part via down-regulation of FGFR1/FGFR2, then decreasing bFGF-stimulated activation of ERK1/ERK2, followed by inhibition of COX-2 activation, and finally DNA synthesis.
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PMID:Dexamethasone inhibits basic fibroblast growth factor-stimulated gastric epithelial cell proliferation. 1869 28

Nonsteroidal anti-inflammatory drugs (NSAIDs) are combined with paracetamol (PCM) with a view to enhance analgesic efficacy and reduce gastric toxicity. However, there are reports of enhanced nephrotoxicity with nonselective NSAID with PCM combinations. The present study investigated the analgesic efficacy, gastrotoxicity and nephrotoxicity of nonselective, preferential and selective cyclooxygenase inhibitors and their combination with PCM in rats. Graded doses of ibuprofen, meloxicam and celecoxib alone and their combination with fixed dose of PCM were administered to the rats by gavage for 14 days. The results showed that PCM potentiated the analgesic effect of all three classes of NSAIDs significantly as evidenced by increase in tail-flick latency in radiant heat method. Dose-dependent gastromucosal damage was produced by all the drugs, which was augmented significantly with PCM in the form of decreased total carbohydrate/protein ratio of mucin and increased gastric ulcer index. It was further confirmed by histopathology of rat's stomach. The renal histopathology was conducted to evaluate inflammation, tubular damage, papillary necrosis, and interstitial changes. Increased nephrotoxicity was observed with all NSAIDs in dose-dependent manner and in combination with PCM. Our study revealed the augmented analgesia as well as enhanced gastrotoxicity and nephrotoxicity with all three major NSAIDs classes when combined with PCM. These findings highlighted the need for large pharmacoepidemiological studies to evaluate the magnitude of gastrotoxicity and nephrotoxicity in population who are on long-term treatment with NSAID combinations.
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PMID:Evaluation of analgesic efficacy, gastrotoxicity and nephrotoxicity of fixed-dose combinations of nonselective, preferential and selective cyclooxygenase inhibitors with paracetamol in rats. 1980 Feb 6

In this study, the anti-inflammatory and anti-ulcerative effects of metyrosine, a selective tyrosine hydroxylase enzyme inhibitor, were investigated in rats. For ulcer experiments, indomethacin-induced gastric ulcer tests and ethanol-induced gastric ulcer tests were used. For these experiments, rats were fasted for 24 h. Different doses of metyrosine and 25 mg/kg doses of ranitidine were administered to rats, followed by indomethacin at 25 mg/kg for the indomethacin-induced ulcer test, or 50% ethanol for the ethanol-induced test. Results have shown that at all of the doses used (50, 100 and 200 mg/kg), metyrosine had significant anti-ulcerative effects in both indomethacin and ethanol-induced ulcer tests. Metyrosine doses of 100 and 200 mg/kg (especially the 200 mg/kg dose) also inhibited carrageenan-induced paw inflammation even more effectively than indomethacin. In addition, to characterize the anti-inflammatory mechanism of metyrosine we investigated its effects on cyclooxygenase (COX) activity in inflammatory tissue (rat paw). The results showed that all doses of metyrosine significantly inhibited high COX-2 activity. The degree of COX-2 inhibition correlated with the increase in anti-inflammatory activity. In conclusion, we found that metyrosine has more anti-inflammatory effects than indomethacin and that these effects can be attributed to the selective inhibition of COX-2 enzymes by metyrosine. We also found that adrenalin levels are reduced upon metyrosine treatment, which may be the cause of the observed gastro-protective effects of this compound.
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PMID:Gastric anti-ulcerative and anti-inflammatory activity of metyrosine in rats. 2036 Jun 21

Gastric ulcer is a multifaceted process that involves reactive oxygen species (ROS) generation, extracellular matrix degradation and mitochondrial damage. Mitochondria play a crucial role for homeostasis of ROS and cell survival. In our study, we investigated the efficacy and mechanism of polymeric nanocapsuled quercetin (NQC) over the free quercetin (QC) molecule in prevention of ethanol-induced gastric ulcer in rat. NQC possessed significantly higher efficacy (~20 fold) than free QC while preventing gastric ulcers. Our data show that prior administration of NQC and/or QC significantly blocked synthesis and secretion of matrix metalloproteinase (MMP)-9 as well as infiltration of inflammatory cells and oxidative damage in rat gastric tissues. As compared to free QC, NQC protected much better the mitochondrial integrity and size along with mitochondrial functions by controlling succinate dehydrogenase and NADH oxidase in rat gastric tissues. In addition, both free QC and NQC down regulated PARP-1 as well as apoptosis during protection against ethanol-induced gastric ulcer. Herein, the effect of NQC was greater than QC on expression of enzymes like cyclooxygenase and nitric oxidase synthase (NOS)-2. We conclude that NQC with greater bioavailability offers significantly higher potency in downregulating MMP-9 and NOS-2 as well as oxidative stress in blocking ethanol-induced gastric ulcer.
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PMID:The use of nano-quercetin to arrest mitochondrial damage and MMP-9 upregulation during prevention of gastric inflammation induced by ethanol in rat. 2225 24


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