Zinc-mediated activation of CREB pathway in proliferation of pulmonary artery smooth muscle cells in pulmonary hypertension

Abstract

Plain English summary Transcription factor CREB plays an important role in the development of pulmonary hypertension (PH). However, paradoxical roles have been reported in the pathogenesis of PH, and the regulatory mechanisms of CREB activation in pulmonary artery smooth muscle cells (PASMCs) proliferation remained unknown. In this study, we showed that CRE-containing genes were overrepresented among the differentially expressed genes in experimental PH, which resulted from the sustained activation of CREB pathway. The sustained activation of CREB pathway may be associated with the activation of multiple protein kinases that positively regulate CREB and down-regulation of numerous phosphatases involved in CREB dephosphorylation. Additionally, we found that the proliferation of PAMSCs was dependent on the CREB-mediated transcriptional activity in experimental PH. Moreover, the raised intracellular labile zinc possibly from ZIP12 may be associated with reduced protein phosphatases, increased CREB-mediated transcriptional activity and PASMCs proliferation. Collectively, we found CREB-mediated transcriptional activity in the proliferation of PASMCs in PH, which may be associated with multiple protein kinases and/or reduced phosphatases and elevated intracellular zinc. This study may reveal a critical role of zinc-mediated activation of CREB pathway in the proliferation of PASMCs, thus providing a more comprehensive understanding of CREB pathway in the pathogenesis of PH.

Keywords

• Pulmonary hypertension
• Pulmonary artery smooth muscle cells proliferation
• CREB
• Protein phosphatases
• Intracellular labile zinc