절식이 랫트 간의 황함유 아미노산 대사에 미치는 영향

• 영문명: Effects of Fasting on Hepatic Metabolism of Sulfur Amino Acids in Rats
• 발행기관: 대한약학회
• 저자명: 김상겸(Sang Kyum Kim)
• 간행물 정보: 『약학회지』제53권 제2호 (2009년), 74~77쪽, 전체 4쪽
• 주제분류: 의약학 > 기타의약학
• 파일형태: PDF
• 발행일자: 2009.04.30

영문 초록

Food deprivation decreases hepatic glutathione (GSH) levels, which is ascribed to alterations in availability of hepatic cysteine, a rate limiting factor for the GSH synthesis. The present study examines the effects of food deprivation on hepatic metabolism of sulfur amino acid in male rats. In rats fasted for 24 or 48 hours, hepatic GSH levels were decreased from 6.70±0.16 |imol/g liver to 4.02±0.20 or 4.06±0,07 나mol/g liver, respectively. Hepatic S-adenosylmethionine levels were also decreased in fasted rats, but S- adenosylhomocysteine levels were increased. Hepatic methionine levels were not changed by food deprivation for 48 hours. On the other hand, hepatic cysteine or taurine levels were increased from 106.2±4.1 to 130.0±2,7 nmol/g liver or from 2.45±0.43 to 5.07±0.78 |^mol/g liver, respectively, in 48-hour fasted rats. Activity of cystathionine beta-synthase catalyzed homocysteine to cystathionine, was markedly decreased, but activity of betaine homocysteine methyltransferase was increased in fasted rats, indicating that methylation of homocysteine to methionine is activated. Also activity of cysteine dioxygenase, involved in taurine synthesis, was increased. These results suggested that hepatic methionine levels were maintained in rats fasted for 48 hours through increase in homocysteine methylation, and hepatic GSH may serve as a cysteine supplier reservoir in fasting state.

키워드

fasting sulfur amino acid hepatic metabolism transsulfuration