Phosphoglucose isomerase directs the inflammatory response, calcium influx and fibroblast migration in keloids

AIM: Keloids are regarded as an inflammatory skin disease with altered metabolic demands. Calcium ions are known to regulate cell movement. Phosphoglucose isomerase (PGI) not only balances glucose metabolism but also acts as a multifunctional cytokine, as those calcium ions do. Here, for the first time, we aimed to explore the intracellular calcium level controlled by PGI in keloid fibroblasts (KFs) and normal fibroblasts (NFs). In addition, whether PGI regulates the biological functions of KFs via the inflammatory status was investigated. METHODS: The inflammatory status, fibrotic activity, and migration ability of KFs and NFs were evaluated via RT-PCR, western blot analysis, and scratch assay. We inhibited PGI with erythrose 4-phosphate (ER4P) to determine whether PGI regulates KF migration. RESULTS: The upregulation of PGI expression was measured in both KFs and keloid tissues. Suppressing PGI inhibited SMA and type I collagen expression, and cell migration in KFs. Indeed, PGI regulated inflammation and calcium influx in KFs. CONCLUSIONS: Our study is the first to show that PGI regulates the migration of KFs via a calcium influx-dependent inflammatory response and that blocking PGI might be a therapeutic strategy for keloids.