Exposure of Human Endothelial Progenitors to Sevoflurane Improves Their Survival Abilities

Endothelial progenitor cells (EPCs) have prominent roles in vessel and tissue repair; however, their regenerative efficacy is diminished due to the poor survival in the hostile microenvironment of the injured organs. Recent data suggest a promising potential of volatile anesthetics for improving stem cell biology. Thus, we hypothesized that exposure to sevoflurane could stimulate growth and viability of cultured EPCs. Total mononuclear cells were isolated from human umbilical cord blood by gradient centrifugation. After five days in culture, the cells were exposed for one or two hours to sevoflurane 2% or 4% in air/5% CO2, or only to air/5% CO2 (sham control) in a sealed modular chamber. 24 or 48 hours post-exposure, viability, proliferation and apoptosis were assessed using lactate dehydrogenase (LDH) leakage assay, a methyl tetrazolium salt (MTS) assay and FITC-annexin V/ propidium iodide (PI) staining, respectively. LDH leakage was discretely lowered, whereas the levels of formazan were significantly increased (p < 0.05 for 1 h incubation with 4% sevoflurane at 24 hrs post-exposure, and with 2% sevoflurane at 48 h post-exposure) in the preconditioned cultures, proving no cytotoxic effects and increased proliferation in treated cells versus control samples. Early (p < 0.05) and late apoptosis (p < 0.05 only for 2% sevoflurane) were diminished following the procedure. Thus, the commonly used sevoflurane anesthetic has protective effects on viability and proliferation of human early endothelial progenitor cells in vitro, suggesting a promising potential of anesthetic preconditioning for improving the regeneration of ischemic tissues.