Effect of “mega dose” of vitamin C on polyamine oxidase activity in hepatic tissue or rats

Abstract

EFFECT OF MEGA DOSE OF VITAMIN C ON POLYAMINE OXIDASE ACTIVITY IN HEPATIC TISSUE OR RATS G. Bjelakovi~, G.B. Bjelakovi~ 1, I. Stojanovi~, B.B. Bjelakovi6, T. Jeftovi6 Institute of Biochemistry, Clinic of Hepati-Gastroenterology, Serbia, Yugoslavia. 1Faculty of Medicine, Serbia, Yugoslavia. Polyamine oxidase (PAO) is a key enzyme in the biodegradation of polyamines. Oxidation of spermine and spermidine by PAO results in the generation of reactive aminoialdehydes, hydrogen peroxide and ammonia. L-ascorbic acid serves as effective antioxidant or at the same time pro-oxidant. In the present paper we have examined the polyamine oxidase activity and the amount of malondialdehyde in the hepatic tissue of rats treated with mega of vitamin C. The experimental animals were treated with the L-ascorbic acid in a daily dose of 12,5 mg/kg body weight intra peritonealy through fourteen days. The control animals group received 0.155 mmol/1 NaC1. Our obtained results show that the treatment of rats with ascorbic acid causes the significant decrease of polyamine oxidase activity (2.878 (0.063 U/rag prot. in the control group) and (1.752 (0.056 in the exp. group, P (0.05). The amount of MDA in the liver of animals treated with high dose of vitamin C increases (MDA in the experimental group 0.562 (0.574 nmol/mg prot. and MDA in the control group 0.327 (0.634 nmol/mg prot. P (0.001). The higher amount of malondialdehyde in the experimental group is probably a reflex of vitamin C prooxidant effects at the level of hepatic tissue. I C11/15 I