HIF1A and pulmonary arterial hypertension: Additionally, the transplantation of mesenchymal stem cells into rats with MCT-PAH, followed by stimulation with prostaglandin E1, resulted in increased expression of HIF-1α.413 This upregulation enhanced the migration of mesenchymal stem cells to the injury site by increasing SDF-1α/CXCR4 expression, ultimately alleviating PH.413 These findings suggest that HIF-1α may play varying roles in stem cells, indicating that stem cell therapy could emerge as a promising approach for treating PH and provide a new direction for future research.