The effect of glucose feeding on fatty acid synthesis in human platelets

Platelets were isolated from volunteers who had fasted for 15 hours and again 1 hour after these subjects had ingested glucose. After feeding, incorporation of (C¹⁴) acetate into fatty acids of washed platelets was increased 68 per cent. Ingestion of fructose produced a comparable stimulation of fatty acid synthesis, but ingestion of galactose had no effect. Pre-incubation of the whole blood from fasting donors with glucose prior to incubation of the platelets did not increase the subsequent incorporation of (C¹⁴) acetate by washed cells. Ingestion of glucose did not alter the level of glycogen or of lactate in platelets, nor did it alter their rate of glycogenolysis or of lactate production. Similarly, evolution of ¹⁴CO₂ from [1-¹⁴C] or [6-¹⁴C] glucose or from [1-¹⁴C] acetate was unchanged by feeding. The results suggest that the stimulatory effect of feeding glucose or fructose on fatty acid synthesis in platelets is not due to increased availability of these sugars to the cell. It is conceivable that a humoral factor is released by ingestion of glucose or fructose which stimulates lipogenesis in platelets.