Increased \u03b2-adrenergic stimulation augments vascular smooth muscle cell calcification via PKA/CREB signalling

Barbara Moser,Florian Poetsch,Burkert Pieske,Trang T D Luong,Ioana Alesutan,Jakob Voelkl,Florian Lang,Misael Estepa

doi:10.1007/s00424-021-02621-3

Abstract

In chronic kidney disease (CKD), hyperphosphatemia promotes medial vascular calcification, a process augmented by osteogenic transdifferentiation of vascular smooth muscle cells (VSMCs). VSMC function is regulated by sympathetic innervation, and these cells express α- and β-adrenergic receptors. The present study explored the effects of β2-adrenergic stimulation by isoproterenol on VSMC calcification. Experiments were performed in primary human aortic VSMCs treated with isoproterenol during control or high phosphate conditions. As a result, isoproterenol dose dependently up-regulated the expression of osteogenic markers core-binding factor α-1 (CBFA1) and tissue-nonspecific alkaline phosphatase (ALPL) in VSMCs. Furthermore, prolonged isoproterenol exposure augmented phosphate-induced calcification of VSMCs. Isoproterenol increased the activation of PKA and CREB, while knockdown of the PKA catalytic subunit α (PRKACA) or of CREB1 genes was able to suppress the pro-calcific effects of isoproterenol in VSMCs. β2-adrenergic receptor silencing or inhibition with the selective antagonist ICI 118,551 blocked isoproterenol-induced osteogenic signalling in VSMCs. The present observations imply a pro-calcific effect of β2-adrenergic overstimulation in VSMCs, which is mediated, at least partly, by PKA/CREB signalling. These observations may support a link between sympathetic overactivity in CKD and vascular calcification.

Highlights

Chronic kidney disease (CKD) is associated with high mortality due to cardiovascular disease [23, 71]
A first series of experiments investigated the effects of chronic β-adrenergic stimulation on markers of osteogenic transdifferentiation of vascular smooth muscle cells (VSMCs)
human aortic smooth muscle cells (HAoSMCs) were treated with increasing concentrations of isoproterenol, a nonspecific β-adrenergic receptor agonist, and the expression of osteogenic transcription factor core-binding factor α-1 (CBFA1) and osteogenic enzyme ALPL was determined

Summary

Introduction

Chronic kidney disease (CKD) is associated with high mortality due to cardiovascular disease [23, 71]. Vascular calcification is an active process involving transdifferentiation of vascular smooth muscle cells (VSMCs) into cells with some osteo-/ chondroblast-like properties, characterized by expression of osteogenic transcription factors and enzymes [4, 15, 73]. Core-binding factor α-1 (CBFA1/RUNX2) is an osteogenic transcription factor essential for vascular calcification [60, 62], which induces expression of osteogenic enzymes, including tissue-nonspecific alkaline phosphatase (ALPL) [21, 62], a key effector of vascular mineralization [21, 73]. In CKD, hyperphosphatemia is considered the key pathological factor triggering osteogenic transdifferentiation of VSMCs and vascular calcification [73].

Methods

Results

Conclusion