Effects of High Sucrose or Starch-bran Diets on Glucose and Lipid Metabolism of Normal and Diabetic Rats

Abstract

Normal and streptozotocin-diabetic rats were fed a low carbohydrate diet or one of two high carbohydrate diets (sucrose or starch-bran). High carbohydrate diets were associated with slightly higher plasma glucose levels in both control and diabetic rats. However, glucose tolerance tests were not altered by the diets in either the control or diabetic rats. Plasma and liver triglyceride values for control and diabetic rats fed the high sucrose diet were similar to those of rats fed the low carbohydrate diet. The starch-bran diet was associated with lower plasma and liver triglyceride values in both control and diabetic rats. Plasma triglyceride values of diabetic rats fed the high sucrose diet or the low carbohydrate diet were significantly higher than values of control rats fed the same diets. On the other hand, plasma triglyceride values of diabetic rats fed the starch-bran diet were similar to values for control rats fed the same diet. These studies suggest that a high carbohydrate diet containing starch and wheat bran is associated with a reduction in plasma triglyceride values in both normal and diabetic rats. Liver glycolytic enzyme activities were significantly lower in diabetic rats than in control rats in all three dietary groups.

Effect of Soybean Crude Fiber on the Concentrations of Serum Lipids and Apolipoproteins in Hyperlipemic Subjects

“…Plant fiber does influence the absorption and metabolism of triglycer ides and fatty acids and is usually accompa nied by a reduction in total lipid and triglyc eride content of the liver in experimental ani mals [23,24], Since lower postprandial insu lin levels have been reported after a fiber-rich meal including fiber-rich soybean [17,25], a decreased synthesis of fatty acids and triglyc erides would be expected. However, the crude soybean fiber used in this study con tains lipids and proteins other than fiber which may contribute to the reduction in serum triglyceride levels.…”

Minimal chronic hyperglycemia is a critical determinant of impaired insulin secretion after an incomplete pancreatectomy.

“…Although we did not measure how much chow was consumed by the different groups, others have shown using similar systems in normal rats that it is reduced by a third while total calorie intake is 20% higher (14,15), which results in an overall decrease in protein and fat intake while carbohydrate intake is increased. It has been clearly demonstrated that a low protein-hypocaloric diet tends to depress insulin secretion (16,17), but when carbohydrate is added to make up the missing calories, secretory responses are unchanged (18 normal rats (19)(20)(21), but this remains controversial (22)(23)(24). More germane to our results, a recent study failed to find any decrease in glucose-induced insulin secretion assessed with the perfused pancreas when normal rats were given a high sucrose diet for a month (25).…”

Postheparin Lipolytic Activities in Zucker Rats Fed with Sucrose- or Cornstarch-Rich Diets

“…The hypertriglyceridemia of the Zucker rats has also been shown to be highly suscep tible to stimulation by high carbohydrate in take [Ellwood and Michaelis, 1980], and a great increase of triglyceride levels in rats fed ad libitum with a sucrose-rich compared to cornstarch diets has been reported [Hallfrisch et al, 1979;Lin and Anderson, 1977;AlNagdy et al, 1970], Lipoprotein lipase activity (mainly from fat and heart origin) is under hormonal and nutritional control. Recently Basilico et al [1983] have shown that the plasma H-TGL and MGH activities could also be regulated by hormones and diets.…”

“…Sucrose-rich diets as compared to starch diets produce a considerable increase in plasma triglyceride as well as increased insu lin secretion and an abnormal glucose toler ance, both in normal rats and in man [Hallfrisch et al, 1979;Lin and Anderson, 1977;Lombardo et al" 1983;Al-Nagdyel al., 1970;Laube et al, 1978]. Concerning Zucker's fa/fa rats, De H'aard [1978] has shown that the sucrose effect (sucrose versus starch) fur ther enhanced plasma triglyceride levels after 2 weeks of feeding.…”