Tappenden, Kelly A.; Martin, Amy; Layman, Donald K.; Baum, Jamie Ilene
Journal Name- Faseb Journal
Vol. 15
No. 4
March 7, 2001
PP. A301.
Document Type- Meeting
Issn- 0892-6638
Address- University Of Illinois At Urbana-Champaign, 905 S. Goodwin Ave, 430 Bevier Hall, Urbana, Il, 61801, Usa
Conference Date- March 31-April 04, 2001
Conference Title- Annual Meeting Of The Federation Of American Societies For Experimental Biology On Experimental Biology 2001
Language- English Ndn- 199-0109-5993-5
Inhibitors of carbohydrate digestion are thought to blunt glucose uptake and potentially modify glucose homeostasis and weight loss. However, questions remain concerning activity of the inhibitor in vivo and concentrations required to modify starch digestion. To test the durability of amylase inhibitor under conditions of the GI tract, we used an inhibitor (I: approx. MW 49,000) purified from Great Northern beans. Preliminary in vitro dose-response studies indicate that concentrations of the 1 at 0.2 muM produced complete inhibition of purified porcine amylase under conditions of intestinal pH. Further, addition of I to chyme isolated from the upper jejunum of rats also produced complete inhibition of amylase activity. Based on the in vitro dose-response studies, an in vivo study was conducted with rats using a 600 mOsm amino acid solution to simulate enteral feeding and designed to stimulate pancreatic secretion of amylase. The study was conducted as a cross-over design with 3 consecutive infusions spaced 15 min apart. The first infusion was either 3 ml of the AA solution or the AA plus 60 mg of I infused into the stomach, followed by 3 ml of saline, and a third infusion of 3 mls of the matching solution: Intestinal chyme was collected at the proximal end of the jejunum and tested for amylase activity. Infusion of the inhibitor decreased amylase activity by 50 - 75%. These results indicate that amylase inhibitor is effective in reducing amylase activity in vivo and supports the hypothesis that an amylase inhibitor may reduce or delay carbohydrate digestion and glucose absorption.