Secretome of Hypoxia-Preconditioned Mesenchymal Stem Cells Enhance Angiogenesis in Diabetic Rats with Peripheral Artery Disease.

Background: Lower limb peripheral artery disease (PAD) is the main risk of diabetes mellitus which result to high mortality rate. Approximately, 50% of patients who receive several treatments have passed away or lost limbs at a year's follow-up. Secretome of hypoxia mesenchymal stem cells (S-MSCs) contains several active soluble molecules from hypoxia MSCs (H-MSCs) that capable inducing anti-inflammatory and vascular regeneration in PAD.

Objective: In this study, we investigated the therapeutic potential of S-MSCs in improving dynamic function and angiogenesis of PAD diabetic rats.

Methods: The PAD was established by the incision from the groin to the inner thigh and distal ligation of femoral arteries in rats with diabetes. Rats were administered with 200 µL and 400 µL S-MSCs that successfully filtrated using tangential flow filtration (TFF) system based on various molecular weight cut-off categories intravenously. ELISA assay was used to analyze the cytokines and growth factors contained in S-MSCs. Tarlov score were examined at day 1, 3, 5, 7, 10 and 14. The rats were sacrificed at day 14 and muscle tissues were collected for immunohistochemistry (IHC) and gene expression analysis.

Results: ELISA assay showed that S-MSCs provides abundant level of VEGF, PDGF, bFGF, IL-10 and TGFβ. In vivo administration of S-MSCs remarkably enhanced the Tarlov score. S-MSCs improved angiogenesis through enhancing VEGF gene expression and significantly increasing CD31 positive area in muscle tissue of PAD diabetic rats.

Conclusion: Our findings suggest that S-MSCs could improves dynamic function and angiogenesis in PAD diabetic rats.