Antidiabetic effects and mechanisms of action of γ-conglutin from lupin seeds
Mrunmai Tapadia, Stuart Johnson, Ranjeet P. Utikar, Philip Newsholme, Rodrigo Carlessi
Abstract
The glucose modulating properties of lupin have been attributed to its seed protein γ-conglutin. Here we explored the antidiabetic potential of γ-conglutin purified from lupin seeds in-vitro . To mimic the effects of an orally administered supplement, purified γ-conglutin was hydrolysed by gastrointestinal proteolytic enzymes and the resulting peptides evaluated for their antidiabetic effects in pancreatic β-cells and primary human skeletal muscle myotubes. γ-conglutin peptides did not promote insulin secretion in β-cells but elicited a potent insulin-mimetic action by activating insulin signalling pathways responsible for glycogen, protein synthesis , and glucose transport into myotubes. Additionally, the peptides potently suppressed the activity of DPP4 indicating their potential to increase the half-life of incretin hormones in circulation. These results substantiate the health benefits of consuming lupin seeds as part of a healthy diet and can drive the current market for lupins from primarily stockfeed, towards value-added lupin-based food products for human consumption.