INS and type 2 diabetes mellitus: In T2D models, saponins [16], flavonoids [17], and polysaccharides [18] regulate pancreatic β-cell proliferation and insulin-signaling pathways by enhancing the activation of peroxisome proliferator-activated receptor-γ (PPAR-γ), which is a transcription factor belonging to the nuclear receptor family and expressed in a variety of tissues [19].