RESUMO
The antioxidant effects of natural vitamin B(6) compounds on Schizosaccharomyces pombe cells treated with menadione sodium bisulfite (water-soluble menadione and a generator of superoxide, MSB) and the mechanism underlying the function were examined with the yeast cells treated with pyridoxal 5'-phosphate. Vitamin B(6) compounds showed no ex vivo reactivity toward MBS at pH 5.5 or 7.0. The yeast cells showed no growth in the medium containing 1.0 mM MSB. The coexistence of 1.0 mM of each vitamin B(6) compound supported the growth of the yeast cells. The efficacy order was pyridoxal 5'-phosphate>/=pyridoxamine 5'-phosphate>pyridoxamine>pyridoxal>/=pyridoxine. The first three compounds showed higher antioxidant activity than vitamin C did. Pyridoxal 5'-phosphate prevented the reduction of the glutathione content in the MSB-treated cells and, in turn, suppressed the increases in peroxide and thiobarbituric acid reactive substances in the yeast cells and increased the viability of the yeast cells under oxidative stress. The antioxidant function of pyridoxal 5'-phosphate was not dependent on the phosphorelay pathway, which finally triggers the expression of the catalase gene.
Assuntos
Espécies Reativas de Oxigênio/metabolismo , Schizosaccharomyces/efeitos dos fármacos , Vitamina B 6/análogos & derivados , Vitamina B 6/farmacologia , Vitamina K 3/farmacologia , Antifibrinolíticos/farmacologia , Antioxidantes/química , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Sobrevivência Celular , Glutationa/metabolismo , Estrutura Molecular , Estresse Oxidativo , Peróxidos/metabolismo , Fosfato de Piridoxal/farmacologia , Schizosaccharomyces/citologia , Schizosaccharomyces/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Vitamina B 6/metabolismoRESUMO
A new nonsteroidal anti-inflammatory agent, fentiazac, was used for analgesia after tooth extractions and minor oral surgery in two Japanese dental hospitals. The drug was administered as a single oral dose of either 50 mg or 100 mg. The 50-mg dose provided rapid analgesic effect, but its effect lasted only two to three hours in a number of patients. At a dose of 100 mg, fentiazac proved effective for 85% of 53 patients, usually providing marked reduction of disappearance of pain within one hour or less. Among patients in whom pain reappeared, the mean time for recurrence was four hours, indicating a satisfactory duration of analgesic effect. One side effect--loss of appetite--was reported by one patient in the entire series of 71 subjects. It is concluded that fentiazac is a highly effective analgesic agent with a wide margin of safety for use after dental procedures that produce pain.