The effect of phosphorus manipulation on in vivo glycogenesis and lipogenesis of rats fed a high fructose diet

Abstract

Objective: High phosphorus intake was reported to be associated with the development of metabolic syndrome. This effect is though to be related to its capacity to induce lipogenesis and uric acid production. Fructose is also known to have phosphorus sequestering capacity, but it is not clear whether phosphorus manipulation of the diet would affect fructose metabolism and thus its capacity to induce metabolic syndrome.

Methods: Adult male Sprague-Dawley rats were maintained for four days on high fructose diet with different added quantities of phosphorus (0%, 0.015%, 0.15% and 1.5%). Food intake and body weight were monitored throughout the experiment. At the end of the feeding period, overnight fasted rats were fed a test meal and injected with 3H2O to measure in vivo rates of glycogen and lipid synthesis.

Results: Postprandial lipogenesis of both epididymal fat pad and liver was found to increase with increased phosphorus content of the diet. At the same time, postprandial hepatic glycogenesis increased with increased phosphorus content of the diet. But, plasma uric acid concentration was similar among the groups.

Conclusion: Increased phosphorus content of high fructose diet seems to stimulate the lipogenic capacity of both liver and adipose tissue. This in turn may promote the development of hypertriglyceridemia and thus metabolic syndrome.