Inhibitory effect and mechanism of acarbose combined with gymnemic acid on maltose absorption in rat intestine.
OBJECTIVE
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 (0.1g/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 3h 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 1g/L GA in vivo indicating that the combined effects involved the functional alteration of intestinal barriers.


CONCLUSIONS
There are augmented effects of acarbose and GA,which involve pre-cellular and paracellular barriers. Diabetic care can be improved by employing the combination.
Luo
H
H
Department of Physiology, the Institute of Basic Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, 5 Dongdansantiao Beijing 100005, China.
Wang
L F
LF
Imoto
T
T
Hiji
Y
Y
D020909:Acarbose / Q000494:pharmacology*; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D005769:Gastrointestinal Motility / Q000187:drug effects; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D066298:In Vitro Techniques; D007408:Intestinal Absorption / Q000187:drug effects* / Q000502:physiology; D007421:Intestine, Small / Q000187:drug effects / Q000502:physiology; D008297:Male; D008320:Maltose / Q000493:pharmacokinetics*; D051381:Rats; D017208:Rats, Wistar; D012503:Saponins / Q000494:pharmacology*; D014315:Triterpenes / Q000494:pharmacology*
D007004:Hypoglycemic Agents; D012503:Saponins; D014315:Triterpenes; C007898:gymnemic acid; D008320:Maltose; D020909:Acarbose