PDGF-D activation by macrophage-derived uPA promotes AngII-induced cardiac remodeling in obese mice

Obesity-induced secretory disorder of adipose tissue-derived factors is important for cardiac damage. However, whether platelet-derived growth factor-D (PDGF-D), a newly identified adipokine, regulates cardiac remodeling in Angiotensin II (AngII)-infused obese mice is unclear. Here, we found obesity induced PDGF-D expression in adipose tissue, as well as more severe cardiac remodeling compared to control lean mice after AngII infusion. Adipocyte-specific PDGF-D knockout attenuated hypertensive cardiac remodeling in obese mice. Consistently, adipocyte-specific PDGF-D overexpression transgenic mice (PA-Tg) showed exacerbated cardiac remodeling after AngII infusion without high-fat diet treatment. Mechanistic studies indicated that AngII-stimulated macrophages produce urokinase plasminogen activator (uPA) that activates PDGF-D by splicing full-length PDGF-D into the active PDGF-DD. Moreover, bone marrow specific uPA knockdown decreased active PDGF-DD level in the heart and improved cardiac remodeling in HFD hypertensive mice. Together, our data provide for the first time a new interaction pattern between macrophage and adipocyte, that macrophage-derived uPA activates adipocyte-secreted PDGF-D, which finally accelerates AngII-induced cardiac remodeling in obese mice. Overall design: mRNA profiles of primary cardiac fibroblasts with or without PDGF-DD treatment.6 samples are analyzed, including 3 replicates of control samples and 3 replicates of PDGF-DD treated samples.