Effectiveness and safety of human umbilical cord-mesenchymal stem cells for treating type 2 diabetes mellitus

BACKGROUND Progressive pancreatic beta-cell dysfunction is a fundamental part of the pathology of type 2 diabetes mellitus (T2DM). Cellular therapies offer novel opportunities for the treatment of T2DM to improve the function of islet beta-cells. AIM To evaluate the effectiveness and safety of human umbilical cord-mesenchymal stem cell (hUC-MSC) infusion in T2DM treatment. METHODS Sixteen patients were enrolled and received 1 x 10(6 )cells/kg per week for 3 wk as intravenous hUC-MSC infusion. The effectiveness was evaluated by assessing fasting blood glucose, C-peptide, normal glycosylated hemoglobin A1c (HbA1c), insulin resistance index (homeostatic model assessment for insulin resistance), and islet beta-cell function (homeostasis model assessment of beta-cell function). The dosage of hypoglycemic agents and safety were evaluated by monitoring the occurrence of any adverse events (AEs). RESULTS During the entire intervention period, the fasting plasma glucose level was significantly reduced [baseline: 9.3400 (8.3575, 11.7725), day 14 +/- 3: 6.5200 (5.2200, 8.6900); P < 0.01]. The HbA1c level was significantly reduced on day 84 +/- 3 [baseline: 7.8000 (7.5250, 8.6750), day 84 +/- 3: 7.150 (6.600, 7.925); P < 0.01]. The patients' islet beta-cell function was significantly improved on day 28 +/- 3 of intervention [baseline: 29.90 (16.43, 37.40), day 28 +/- 3: 40.97 (19.27, 56.36); P < 0.01]. The dosage of hypoglycemic agents was reduced in all patients, of whom 6 (50%) had a decrement of more than 50% and 1 (6.25%) discontinued the hypoglycemic agents. Four patients had transient fever, which occurred within 24 h after the second or third infusion. One patient (2.08%) had asymptomatic nocturnal hypoglycemia after infusion on day 28 +/- 3. No liver damage or other side effects were reported. CONCLUSION The results of this study suggest that hUC-MSC infusion can improve glycemia, restore islet beta-cell function, and reduce the dosage of hypoglycemic agents without serious AEs. Thus, hUC-MSC infusion may be a novel option for the treatment of T2DM.