Protective role of Gremlin-1 in myocardial function

Abstract

Background: Gremlin-1 is a cystine knot protein and is expressed in organs developing fibrosis. Transient ischaemia leads to myocardial fibrosis, a major determinant of impaired myocardial function. Materials and methods: Expression of Gremlin-1 was investigated in infarcted myocardium by real-time PCR, Western blot analysis, histological and immunohistochemistry staining. We further elaborated the colocalization of Gremlin-1 and TGF-β proteins by confocal microscopy and co-immunoprecipitation experiments. The interaction between Gremlin-1 and TGF-β was analysed by photon correlation spectroscopy. Gremlin-1 modulation of the TGF-β-dependent collagen I synthesis in fibroblasts was investigated using ELISA and immunohistochemistry experiments. The effect of prolonged administration of recombinant Gremlin-1 on myocardial function following ischaemia/reperfusion was accessed by echocardiography and immunohistochemistry. Results: Gremlin-1 is expressed in myocardial tissue and infiltrating cells after transient myocardial ischaemia (P