Original Articles
Copyright ©The Author(s) 2001. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Feb 15, 2001; 7(1): 9-15
Published online Feb 15, 2001. doi: 10.3748/wjg.v7.i1.9
Inhibitory effect and mechanism of acarbose combined with gymnemic acid on maltose absorption in rat intestine
Hong Luo, Le Feng Wang, Toshiaki Imoto, Yasutake Hiji
Hong Luo, Toshiaki Imoto, Yasutake Hiji, Departments of Physiology, Faculty of Medicine, Tottori University, Yonago 683-0826, Japan
Le Feng Wang, Internal Medicine, Faculty of Medicine, Tottori University, Yonago 683-0826, Japan
Author contributions: All authors contributed equally to the work.
Supported by Grant for Promotion of Science from Tottori Bioscience Foundation (1997-1998), Japan and Japanese Government (Ministry of Education, Science and Culture of Japan, MONBUSHO) scholarship No. 933241 (1994-1999), Japan in part. Dr. Luo was supported by the scholarships.
Correspondence to: Dr. Hong Luo, Department of Physiology, the Institute of Basic Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, 5 Dongdansantiao Beijing 100005, China
Telephone: 0086-10-65296463 Fax: 0086-10-67611572
Received: May 12, 2000
Revised: June 16, 2000
Accepted: June 23, 2000
Published online: February 15, 2001
Abstract

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.

Keywords: diabetes mellitus, maltose, gymnemic acid, alpha-glucosidases, intestinal mucosa, rats, nutrition