Researchers have found a way to 'toggle' the intestinal enzymes responsible for processing starchy foods on and off, which could lead to better control of those processes in people with Type 2 diabetes.
This "toggling" was discovered in the lab of Simon Fraser University chemist Mario Pinto, who has designed inhibitors capable of regulating each of the four starch-digesting enzymes known as alpha-glucosidases. Three of those enzymes are responsible for generating glucose from starch, each in different ways. A fourth enzyme breaks down sucrose, also giving glucose. Occasionally one or more of the enzymes is missing, which also affects how glucose is created, Pinto explains.
"We wanted to determine whether we could control the release of glucose when starch is broken down in the body," says Pinto, whose work included characterizing each of the four enzymes. Working with a consortium of scientists co-led by Purdue University's Bruce Hamaker, a professor of food science, Pinto says the inhibitors were found to selectively inhibit the enzymes and control starch breakdown.
That means it could be possible to provide the missing enzymes or develop new starches that will digest properly with the enzymes they do have. "It's all about control and using the molecular information we have to control those enzymes," he says. "Selectively inhibiting the enzymes offers the possibility of regulating and directing the release of glucose."
The scientists approached the problem from multi-disciplinary chemical, structural, molecular and cellular perspectives and the discovery could result in the control of blood glucose for Type 2 diabetes as well as other conditions. When enzymes are missing – a common characteristic of a rare disease known as CSID – Pinto says it may be possible to administer one, and design foods in certain ways that other enzymes can break down.
"This is a powerful piece of knowledge," adds Pinto, noting that in the future it may be possible to control the exact delivery of glucose at different points in the small intestine.
Published in the Journal of Biological Chemistry. Authors: Byung-Hoo Lee, Razieh Eskandari, Kyra Jones, Kongara Ravinder Reddy, Roberto Quezada-Calvill, Buford L. Nichols, David R. Rose, Bruce R. Hamaker and B. Mario Pinto