Periostin Augments Vascular Smooth Muscle Cell Calcification via ß-Catenin Signaling.

ABSTRACT

Medial vascular calcification is common in chronic kidney disease (CKD) and is closely linked to hyperphosphatemia. Vascular smooth muscle cells (VSMCs) can take up pro-calcific properties and actively augment vascular calcification. Various pro-inflammatory mediators are able to promote VSMC calcification. In this study, we investigated the effects and mechanisms of periostin, a matricellular signaling protein, in calcifying human VSMCs and human serum samples. As a result, periostin induced the mRNA expression of pro-calcific markers in VSMCs. Furthermore, periostin augmented the effects of ß-glycerophosphate on the expression of pro-calcific markers and aggravated the calcification of VSMCs. A periostin treatment was associated with an increased ß-catenin abundance as well as the expression of target genes. The pro-calcific effects of periostin were ameliorated by WNT/ß-catenin pathway inhibitors. Moreover, a co-treatment with an integrin αvß3-blocking antibody blunted the pro-calcific effects of periostin. The silencing of periostin reduced the effects of ß-glycerophosphate on the expression of pro-calcific markers and the calcification of VSMCs. Elevated serum periostin levels were observed in hemodialysis patients compared with healthy controls. These observations identified periostin as an augmentative factor in VSMC calcification. The pro-calcific effects of periostin involve integrin αvß3 and the activation of the WNT/ß-catenin pathway. Thus, the inhibition of periostin may be beneficial to reduce the burden of vascular calcification in CKD patients.