Microparticles Carrying Peroxisome Proliferator-Activated Receptor Alpha Restore the Reduced Differentiation and Functionality of Bone Marrow-Derived Cells Induced by High-Fat Diet

Metabolic pathologies such as diabetes and obesity are associated with decreased level of circulating and bone marrow (BM)-derived endothelial progenitor cells (EPCs). It is known that activation of peroxisome proliferator-activated receptor alpha (PPAR) may stimulate cell differentiation. In addition, microparticles (MPs), small membrane vesicles produced by activated and apoptotic cells, are able to reprogram EPCs. Here, we evaluated the role of MPs carrying PPAR on both phenotype and function of progenitor cells from mice fed with a high-fat diet (HFD). HFD reduced circulating EPCs and, after 7 days of culture, BM-derived EPCs and monocytic progenitor cells from HFD-fed mice displayed impaired differentiation. At the same time, we show that MPs bearing PPAR, MPs(PPAR+/+), increased the differentiation of EPCs and monocytic progenitors from HFD-fed mice, whereas MPs taken from PPAR knockout mice (MPs(PPAR-/-)) had no effect on the differentiation of all types of progenitor cells. Furthermore, MPs(PPAR+/+) increased the ability of progenitor cells to promote in vivo angiogenesis in mice fed with HFD. The in vitro and in vivo effects of MPs(PPAR+/+) were abolished in presence of MK886, a specific inhibitor of PPAR. Collectively, these data highlight the ability of MPs carrying PPAR to restore the failed differentiation and functionality of BM-derived cells induced by HFD.