Deficiency In The Novel Small Leucin-Rich Repeat Protein Podocan Promotes Pressure Load-Induced Cardiac Hypertrophy

Background: Extracellular matrix (ECM) molecules have been increasingly implicated in cardiac remodeling, and in particular the myocardial response to pressure overload. Podocan is a novel member of the small leucin-rich-repeat protein family of ECM proteins. We recently have characterized podocan as an inhibitor of the migration and proliferation of vascular smooth muscle cells. Now we are testing if podocan deficiency has an effect on pressure load-induced cardiac hypertrophy. Methods and Results: We induced pressure overload cardiac hypertrophy using aortic banding (AB) in mice (age 10-12 weeks) with podocan-/- (n=6) and wild-type (WT) (n=7) genotype. Four weeks after AB, cardiac anatomy and function were assessed by echocardiography. In addition, histological analysis was used to assess the myocardial response to AB. Podocan-deficient mice showed significantly greater cardiac hypertrophy compared with WT mice after AB, whereas no significant differences were observed when comparing sham-operated anima...