Metabolic alterations in human pulmonary artery smooth muscle cells treated with PDGF-BB.

Background: Metabolic abnormalities are considered to play a key regulatory role in vascular remodeling of pulmonary arterial hypertension. However, to date, there is a paucity of research documenting the changes in metabolome profiles within the supernatants of pulmonary artery smooth muscle cells (PASMC) during their transition from a contractile to a synthetic phenotype.

Methods: CCK-8 and Edu staining assays were used to evaluate the cell viability and proliferation of human PASMCs. IncuCyte ZOOM imaging system was used to continuously and automatically detect the migration of the PASMCs. A targeted metabolomics profiling was performed to quantitatively analyze 121 metabolites in the supernatant. Orthogonal partial least squares discriminant analysis was used to discriminate between PDGF-BB-induced PASMCs and controls. Metabolite set enrichment analysis was adapted to exploit the most disturbed metabolic pathways.

Results: Human PASMCs exhibited a transformation from contractile phenotype to synthetic phenotype after PDGF-BB induction, along with a significant increase in cell viability, proliferation, and migration. Metabolites in the supernatants of PASMCs treated with or without PDGF-BB were well profiled. Eleven metabolites were found to be significantly upregulated, whereas seven metabolites were downregulated in the supernatants of PASMCs induced by PDGF-BB compared to the vehicle-treated cells. Fourteen pathways were involved, and pyruvate metabolism pathway was ranked first with the highest enrichment impact followed by glycolysis/gluconeogenesis and pyrimidine metabolism.

Conclusions: Significant and extensive metabolic abnormalities occurred during the phenotypic transformation of PASMCs. Disturbance of pyruvate metabolism pathway might contribute to pulmonary vascular remodeling.