[Continuous blood glucose monitoring: the acute effect of acarbose on blood glucose variations]

Inhibitory effect and mechanism of acarbose combined with gymnemic acid on maltose absorption in rat intestine

AIM: To compare the combinative and individual effect of acarbose and gymnemic acid (GA) on maltose absorption and hydrolysis in small intestine to determine whether nutrient control in diabetic care can be improved by combination of them.

METHODS: The absorption and hydrolysis of maltose were studied by cyclic perfusion of intestinal loops in situ and motility of the intestine was recorded with the intestinal ring in vitro using Wistar rats.

RESULTS: The total inhibitory rate of maltose absorption was improved by the combination of GA (0.1 g/L-1.0 g/L) and acarbose (0.1 mmol/L-2.0 mmol/L) throughout their effective duration (P < 0.05, U test of Mann-Whitney), although the improvement only could be seen at a low dosage during the first hour. With the combination, inhibitory duration of acarbose on maltose absorption was prolonged to 3 h and the inhibitory effect onset of GA was fastened to 15 min. GA suppressed the intestinal mobility with a good correlation (r = 0.98) to the inhibitory effect of GA on maltose absorption and the inhibitory effect of 2 mmol/L (high dose) acarbose on maltose hydrolysis was dual modulated by 1 g/L GA in vivo indicating that the combined effects involved the functional alteration of intestinal barriers.

CONCLUSION: There are augmented effects of acarbose and GA, which involve pre-cellular and paracellular barriers. Diabetic care can be improved by employing the combination.

Dose-response profile of acarbose in older subjects with type 2 diabetes

OBJECTIVE

To examine the dose-response relationship of acarbose, an alpha-glucosidase inhibitor, in older subjects with type 2 diabetes.

RESEARCH DESIGN

Fourteen subjects with type 2 diabetes who were over 65 years old were studied. Five subjects had been treated with diet alone and 9 were receiving a sulfonylurea. The subjects underwent a meal tolerance test in the presence of varying doses of acarbose (0, 25, 50, and 100 mg) on 4 occasions, each 1 week apart. The test meal was chosen to include food items commonly consumed during breakfast in the United States. The 483-kcal meal consisted of 51% of calories in the form of carbohydrates, 14% protein, and 35% fat. The serum glucose, insulin, and triglyceride levels were measured at 0, 1, and 2 hours after the meal.

RESULTS

The postprandial hyperglycemic response to the test meal was significantly reduced with 25 mg of acarbose compared with baseline values. Increasing doses of acarbose to 50 or 100 mg had no significant additional ameliorating effects on postprandial hyperglycemia. Postprandial insulin or triglyceride levels were not significantly altered with single dose acarbose treatment.

CONCLUSIONS

It is concluded that the acute efficacy of acarbose is near maximal at 25 mg when the meal size does not exceed 483 kcal and contains only 61 gm of carbohydrates.