Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.7.6 (RNA polymerase)
 34,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The antiulcer effect of bisdemethoxycurcumin, a yellow pigment found mainly in rhizomes of Curcuma longa, was compared with curcumin in gastric ulcer model systems to validate its clinical application as a remedy for peptic ulcer. Western blot analysis of mouse macrophage cell line RAW 264.7 activated with lipopolysaccharide showed that bisdemethoxycurcumin inhibited inducible nitric oxide synthase (iNOS) production significantly but had no effect on tumor necrosis factor-alpha (TNF-alpha) production, whereas curcumin showed stronger suppression of iNOS protein production and inhibited TNF-alpha protein production significantly. However, bisdemethoxycurcumin and curcumin possessed similar potency in scavenging nitric oxide generated from mouse macrophage cell line RAW 264.7. Reverse-transcriptase polymerase chain reaction (RT-PCR) analysis showed that both curcuminoids inhibited the induction of iNOS dose-dependently at the transcriptional level and curcumin also appeared to inhibit the induction of TNF-alpha at post-transcriptional level. In an animal model, intraduodenal administration of bisdemethoxycurcumin (5-80 mg/kg body wt.) showed a strong inhibitory effect on gastric acid secretion in pylorus-ligated rats whereas curcumin (5-20 mg/kg body wt.) showed a less inhibitory effect, with maximum potency at a dose of 20mg/kg body wt. Moreover, oral administration of bisdemethoxycurcumin at doses of 20-80 mg/kg body wt. twice daily for 10 days showed a significant curative efficacy in accelerating the healing of acetic acid-induced chronic gastric ulcer and promotion of mucosal regeneration in the ulcerated portion in a dose-related manner with potency equal to curcumin. In contrast, the curative potency of curcumin tended to decrease at doses over 160 mg/kg body wt./day. Western blot analysis in ulcerated gastric mucosa showed that bisdemethoxycurcumin dose-dependently reduced the increased protein expression level of iNOS but not TNF-alpha. These results indicated that bisdemethoxycurcumin directly accelerates gastric ulcer healing with potency equal to curcumin. Its antiulcer effect might be due to its properties of decreasing gastric acid secretion and enhancing the mucosal defensive mechanism through suppression of iNOS-mediated inflammation.
 ...
PMID:Comparative antiulcer effect of bisdemethoxycurcumin and curcumin in a gastric ulcer model system. 1918 55

Zn(II)-curcumin, a mononuclear (1:1) zinc complex of curcumin was synthesized and examined for its antiulcer activities against pylorus-ligature-induced gastric ulcer in rats. The structure of Zn(II)-curcumin was identified by elemental analysis, NMR and TG-DTA analysis. It was found that a zinc atom was coordinated through the keto-enol group of curcumin along with one acetate group and one water molecule. Zn(II)-curcumin (12, 24 and 48 mg/kg) dose-dependently blocked gastric lesions, significantly reduced gastric volume, free acidity, total acidity and pepsin, compared with control group (P<0.001) and curcumin alone (24 mg/kg, P<0.05). Reverse transcriptase polymerase chain reaction (RT-PCR) analysis showed that Zn(II)-curcumin markedly inhibited the induction of nuclear factor-kappa B (NF-kappaB), transforming growth factor beta(1) (TGF-beta(1)) and interleukin-8 (IL-8), compared with control group (P<0.05). These findings suggested that Zn(II)-curcumin prevented pylorus-ligation-induced lesions in rat by inhibiting NF-kappaB activation and the subsequent production of proinflammatory cytokines, indicating a synergistic effect between curcumin and zinc. An acute toxicity study showed that mice treated with SDs of Zn(II)-curcumin (2 g/kg) manifested no abnormal signs.
 ...
PMID:Gastroprotective effects of a new zinc(II)-curcumin complex against pylorus-ligature-induced gastric ulcer in rats. 1958 37