Investigating the effect of Quercetin in the presence of CoCl2 as an inducing hypoxia agent on the biological characteristics of human telomerase reverse transcription-immortalized adipose tissue-derived MSCs

Studying the effect of small chemical molecules on stem cell characteristics under normoxia and hypoxia conditions is crucial to discovering the best conditions for effective biomedical applications. This study aimed to investigate the effect of Quercetin (QC; a flavonoid) in the presence of CoCl₂ as a mimicking hypoxia chemical on the biological features of human telomerase reverse transcription-immortalized mesenchymal stem cell (hTERT-MSC) lines. The effect of CoCl₂, QC, and their combination on the viability, proliferation, and migration of hTERT-MSCs were evaluated by MTT, Trypan-blue staining and cell counting by hemocytometer, and in vitro wound healing assays, respectively. Moreover, the effect of treatments on the reactive oxygen species (ROS) production, cell cycle, and HIF1a, c-MET, H19, and CASP3 gene expression was assessed by NBT, PI-staining and flow-cytometry, and real-time PCR assays, respectively. We found that CoCl₂ and QC have different effects on the viability, proliferation, and migration of hTERT-MSCs in a dose-dependent manner. In addition, CoCl₂ and QC affect ROS levels in cells in a dose- and time-dependent manner. While CoCl₂ up-regulated HIF1a, QC and CoCl₂ down-regulated CASP3 and c-MET in hTERT-MSCs. Moreover, QC reduced HIF1a and lncRNA-H19 expression in cells. Furthermore, in the presence of CoCl₂, QC at low concentrations reduced hTERT-MSC survival, proliferation, and migration at 48 h; however, at high concentrations, it induced cell survival and proliferation. The combination treatment also up-regulated ROS levels and down-regulated the investigated genes in cells. Altogether, we conclude that QC at high concentrations under CoCl₂-mediated hypoxia and short exposure time induces hTERT-MSCs survival and proliferation.