Angiogenic and Immunomodulatory effects of embryonic stem cell derived mesenchymal stem cells in a murine model of ischemic hindlimb

In critical limb-threatening ischemia (CLTI), failed revascularization and pharmacotherapy substantially increase amputation and mortality risks. Mesenchymal stem cells (MSCs) are a promising therapeutic option for CLTI. This study evaluated the therapeutic effects of embryonic stem cell-derived MSCs (E-MSCs) on inflammation and angiogenesis under ischemic conditions across different E-MSC doses. Hindlimb ischemia was induced in 85 BALB/c nude mice by cauterizing the femoral and branched arteries. The mice were divided into five groups: non-ischemia (G1); saline-treated ischemia (G2); and ischemia treated with E-MSCs at low, medium, and high doses (G3-G5). Therapeutic effects were assessed using the rotarod test, blood perfusion ratio, and histological and cytokine analyses. G1 exhibited normal blood perfusion and motor function, whereas E-MSC-treated groups (G3-G5) demonstrated improved perfusion compared to G2. Although the medium-dose group (G4) showed numerically greater recovery, differences between G3, G4, and G5 were not statistically significant, suggesting no dose-response. All E-MSC-treated groups exhibited reduced inflammation and increases in motor function and angiogenic factors. Histological analysis revealed enhanced myofiber regeneration, reduced inflammatory infiltration, and diminished collagen deposition in the ischemic muscle of G3-G5. These changes were observed across all dose groups without significant dose-dependent differences. These results suggest E-MSCs enhance blood perfusion and modulate inflammation and angiogenesis in ischemic limbs, regardless of dose. These findings support the therapeutic potential of E-MSCs in CLTI, although further investigation is needed to optimize dosing and elucidate the mechanisms involved.