INS and diabetes mellitus: Investigating the portfolio of other Gymnema species, such as Gymnema montanum (GM) and Gymnema yunnanense (GY), extracts fulfilled some of the properties for having antidiabetic therapeutic potential through being able to (i) preserve β-cell mass via protecting against apoptosis [67] and (ii) reduce blood glucose levels, increase plasma insulin concentrations and maintain beta cell mass in animal model of diabetes in vivo [68,69,70,71,72,73].