Identification of the potential role of <scp>S1PR1</scp> in adult moyamoya disease based on multiple bioinformatics analysis and experimental verification

Moyamoya disease (MMD) is a chronic occlusive cerebrovascular ailment with a progressively rising incidence, yet its precise etiology and pathogenesis remain elusive. Adult MMD-related datasets GSE189993 and GSE157628 were procured from the GEO database for screening of differentially expressed genes (DEGs). Weighted gene co-expression network analysis (WGCNA) was employed to unveil the most significant module associated with MMD. Least absolute shrinkage and selection operator (LASSO) logistic regression was used to identify and validate diagnostic markers for MMD. CIBERSORT and ssGSEA analyses were conducted to estimate immune cell infiltration in MMD vessels. In vitro experiments were performed to validate the biological functions of Sphingosine-1-phosphate receptor 1 (S1PR1) in mouse aortic smooth muscle cells (MOVAS). A total of 436 DEGs were identified from GSE189993, comprising 202 up-regulated genes and 234 down-regulated genes. Within the green-yellow module, 87 genes overlapped with DEGs, and 6 genes were identified by Cytoscape as key factors in the pathophysiology of MMD, namely, platelet endothelial cell adhesion molecule 1 (PECAM1), von Willebrand factor (VWF), intercellular cell adhesion molecule 1 (ICAM1), vascular endothelial growth factor C (VEGFC), tissue-type plasminogen activator (PLAT), and S1PR1. Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses also showed that key genes were mainly involved in endothelial cells and cell adhesion-related biological function. About 13 diagnostic genes were obtained by the LASSO regression algorithm, with S1PR1 emerging as a hub gene demonstrating good diagnostic performance in both the test set and validation set. Finally, we validated that overexpression of S1PR1 spurred viability, proliferation, and cell division in mouse aortic smooth muscle cells (MOVAS) and human cerebral vascular smooth muscle cells (HCVSMC) by activating the PI3K/AKT signaling pathway. S1PR1 has been identified as a hub gene for MMD. S1PR1 overexpression has been linked to enhanced cell division and proliferation in vitro, suggesting its potential as a therapeutic target for adult MMD.