Journal of Functional Foods (Apr 2020)
Lectin rich horsegram protein and myricetin activates insulin signaling – A study targeting PTP1β
Abstract
Horsegram, a rich source of myricetin (Myr), exhibits an anti-hyperglycemic effect. We examined the individual and combinational effect of Myr and horsegram protein (HP) on protein tyrosine phosphatase 1β (PTP1β), and its effect on insulin signaling in high-fat-diet (HFD) and a single dose of streptozotocin (STZ) induced diabetic rat model. Myr, HP, and their combination, Myr + HP, were orally administered to diabetic animals for four weeks. Myr, HP, and Myr + HP were effective in reducing elevated blood glucose, HbA1c, fasting insulin, insulin resistance, oxidative stress markers, and proinflammatory cytokines. Myr ameliorated dyslipidemia and significantly reduced PTP1β activity; HP and Myr + HP were not as effective, although they suppressed the expression of PTP1β. Myr and HP treated groups had elevated levels of the phospho-insulin receptor (pIR), phospho-insulin receptor substrate1 (pIRS1), and phospho-Akt (pAkt), whereas, Myr + HP was not effective. Though myricetin and horsegram proteins ameliorate diabetic conditions, dietary intake of their combination reduced individual efficiency.