Inhibitory effect of the plant proteins mixture on the specific sucrase activity in intestine of diabetic mice

摘要

Increased activity of sucrase, one of the intestinal alpha-glucosidase founded in diabetes mellitus. Inhibition of sucrase activity, plays a major role in preventing rise in postprandial glucose level in diabetics. On peer-reviewed literature could be found regarding investigation the effect of mixture plant proteins, Mw 3 – 15 kDa (MPP), isolated from Astragali radix – Astragalus membranaceus Fisch., Foenugraeci semen – Trigonella foenum graecum L., Cichorii radix – Cichorium Intybus L. and Urticae radix and herba – Urtica dioica L. on sucrase activity. This plants are used in traditional medicine of treatment of diabetes mellitus. The aim of this study was to determine activity of sucrase in small intestinal homogenates of NOD diabetic mice on feeding with and without MPP in chow. In mice diabetes was induced by i.v. injection of aloxan- monohydrate (75 mg/kg b.m.) seven days before treatment with MPP. The proteins (Mw 3 – 15 kDa), were isolated from ethanol extract, each plants separately, by gel filtration method on Sephadex G-25 column. Eluted fraction which highest absorbance on 280 nm were pooled, dialyzed, lyophilized and mixed (MPP) and before treatment in mice solvent in sterile PBS. After seven days of treatment diabetic NOD mice with MPP (1, 8 g/d), the small intestine was removed and divided into three segments, from pylorus to duodenum, and two equal lengths of the jejunum and ileum and homogenized in cold 0.14M KCl. Specific sucrase activity was determined using method of Dahlquist et. al., by sucrose as substrate. We confirmed the increased specific sucrase activity in the intestine of diabetic NOD mice. Our results also indicate that MPP have strongly inhibitory potential on intestinal sucrase activity (p0.05) in diabetic mice. Conclusions drawn from this study should be further supported and our future experiments will be focused on determining the amino acid sequence of each protein from MPP.