DPP4 and diabetes mellitus: In diabetic mouse, DM compromises the BM niches by down-regulating adhesion molecule VCAM1, chemokine SDF-1, pro-angiogenic cytokine VEGF, peptidase DPP-4 and et al. The disturbed stem cells niche leads to stem cells dysfunctions, thereby, impairing the mobilization of HSPCs (Orlandi et al., 2010).