Abstract
Ascorbic acid (AsA) is known to be required for the syn-thesis of carnitine. The present study was designed to clarify the effect of AsA on the carnitine synthesis and lipid metabolism in guinea pigs. The animals were divided into four groups, and fed AsA-free diets for three weeks. Each group was supplemented with AsA in the following doses; high-AsA group, 100mg AsA/day/animal; control group, 5mg AsA/ day/animal; AsA-deficient group, 0.1mg AsA/day/animal; pair-fed group, 5mg AsA/day/animal. The pair-fed group was restricted to the amount of diet consumed by the AsA-deficient group. Tissue carnitine levels of the AsA-deficient group were significantly lower than not only the control group but the pair-fed group. Total cholesterol and phospholipid levels in plasma of the AsA-deficient group were found to be similar to those of the pair-fed group; however, plasma triglyceride levels were significantly higher than that of the pair-fed group. Furthermore, there was an inverse relationship between tissue AsA and plasma triglyceride levels. We concluded that carnitine synthesis and triglyceride metabolism in guinea pigs may be impaired by the decrease of tissue AsA level rather than by the insufficient food intake. It is suggested that tissue carnitine level altered by tissue AsA content affects plasma triglyceride level.
