Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.17.3.2 (xanthine oxidase)
 8,383 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present study was examined whether or not 2-bromoethyamine, a semicarbazide-sensitive amine oxidase (SSAO, EC; 1.4.3.6) inhibitor, would increase an active dopaminergic neurotoxin, 1-methyl-4-phenylpyridinium ion (MPP(+))-induced hydroxyl radical ((*)OH) generation in the rat striatum. Rats were anesthetized, and sodium salicylate (0.5 mM or 0.5 nmol/microl/min) was infused through a microdialysis probe to detect the generation of (*)OH as reflected by the non-enzymatic formation of 2,3-dihydroxybenzoic acid (DHBA) in the striatum. Infusion of 2-bromoethylamine (100 microM or 100 pmol/microl/min) into the striatum drastically increased the formation of (*)OH products, trapped as DHBA by the action of MPP(+). Further, I studied the effect of allopurinol, a xanthine oxidase inhibitor, an 2-bromoethylamine and MPP(+)-induced (*)OH generation. Allopurinol (10 microM or 10 pmol/microl/min) significantly suppressed 2-bromoethyamine and MPP(+)-induced (*)OH. These results suggest that a definite mechanism is not clear at the moment, after inhibition of tissue-bound and/or blood plasma SSAO activity, with consequent increases in bioactive amine levels, enhances the formation of (*)OH products of efflux/oxidation due to MPP(+).
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PMID:Allopurinol suppresses 2-bromoethylamine and 1-methyl-4-phenylpyridinium ion (MPP(+))-induced hydroxyl radical generation in rat striatum. 1627 Dec 80

The wrinkle-fruited leaf flower (Phyllanthus urinaria L.) (Euphorbiaceae) is widely used as a traditional folk medicine for inflammatory relief. Geraniin, the hydrolysable tannin, was purified by a series of chromatographic processes from the 70% aqueous acetone extracts of P. urinaria and identified by NMR [1H (500 MHz) and 13C NMR (126 MHz)] spectra and mass spectroscopy. The scavenging activities of geraniin against DPPH radicals (half-inhibition concentration, IC50, were 0.92 and 1.27 microM, respectively, for pH 4.5 and pH 7.9), hydroxyl radicals (IC50 was 0.11 microM by deoxyribose method and 1.44 microM by electron spin resonance method), and superoxide radicals (IC50 were 2.65 microM) were determined in comparison with positive controls. The inhibitory activities against xanthine oxidase (IC50 were 30.49 microM) were measured. Geraniin also showed dose-dependent inhibitory activities against semicarbazide-sensitive amine oxidase (SSAO, IC50 were 6.58 microM) and against angiotensin converting enzyme (ACE, IC50 were 13.22microM). For kinetic property determinations, geraniin showed competitive inhibitions against SSAO (the apparent inhibition constant, Ki, was 0.70microM) and mixed noncompetitive inhibitions against ACE. Spontaneously hypertensive rats (SHR, 10-week age) were orally administered to once (5 mg geraniin/kg SHR), and changes of systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured over 24 h and compared with the positive control of captopril (2 mg/kg SHR). The geraniin showed antihypertensive activity in lowering SBP and DBP and showed a significant difference from the blank (distilled water) at 2, 4, 6, 8, and 24 h. Healthy food products could use geraniin for antioxidant protection and therapeutic effects in the future.
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PMID:Antioxidant, anti-semicarbazide-sensitive amine oxidase, and anti-hypertensive activities of geraniin isolated from Phyllanthus urinaria. 1849 18