Complex of zinc and lectins from seeds of <em>Vigna radiata </em>as potential anti-diabetic agent

Abstract

BACKGROUND Proteins and phytohemagglutinins from Vigna species have been known to possess α-amylase inhibitory activity. Therefore, it was thought worthwhile to evaluate the lectins from Vigna radiata for antidiabetic activity. The literature reveals that such studies have not yet been carried out. The principal object of this study  is to evaluate antidiabetic activity of the lectins from V. radiata. Another object of this study  is binding of the zinc with the lectins obtained from V. radiata and evaluation of its antidiabetic activity. RESULTS  The V. radiata seed found contain galactose specific lectin.  The MBL-I (Mung Bean Lectin I ) may be a tetrameric protein with molecular weight 160-180 kDa and may be composed of identical or nearly identical relative subunit of molecular weight of 45-50 kDa.  Amino acid analysis of purified Mung bean lectin by reverse phase HPLC revealed that, it contains Glutamate in highest proportion followed by Aspartate and also contains Histidine, which indicates it has good zinc binding potential Binding of the lectins with zinc improved overall stability and efficacy of the lectins.  The antidiabetic acativity was evaluated in Wistar rats using alloxan induced diabetic model and the studies indicated significant (P<0.001) reduction in elevated sugar levels. It’s probable mechanism of antidiabetic action may be insulinomimetic, since, it was found to bind with insulin antibodies in Western Blotting Analysis     CONCLUSION The lectin obtained from V. radiata seed and zinc lectin complex has good potential to be explored as a safe natural antidiabetic agent acting with controlled reduction in blood glucose levels. These findings indicates that the mungbean lectins and zinc lectins complex have tremendous medicinal potential as a herbal antidiabetic drug which need to be explored.