We have evaluated the safety and efficacy of intracoronary human umbilical cord-derived mesenchymal stem cell (hUCMSC) treatment for very old patients with coronary chronic total occlusion. hUCMSCs could improve in the degree of ischemic myocardium, decrease in the infarct size and rise in left ventricular ejection fraction, but the involved mechanisms remain to be fully identified. We analyzed levels of circulating leukocytes, highsensitivity C-reactive protein (hs-CRP), interleukins (ILs), tumor necrosis factor-a (TNF-a), soluble tumor necrosis factor receptor-1 (sTNFR-1), soluble tumor necrosis factor receptor-2 (sTNFR-2), NT-proBNP, BNP, angiotensin 1-7 (Ang1-7), angiotensin II (Ang II) and aldosterone (Ald) in patients with hUCMSC therapy at baseline, 12, and 24 months. Levels of Ang1-7, IL-10, IL-37 and IL-17 were increased at 12 months and 24 months; leukocytes, hs- CRP, IL-1.