Effect of Hypoxic Exercise on Redistribution of Circulating Endothelial Progenitor Cell Subsets

• Main Authors: Mei Yi Lee, 李美誼
• Other Authors: J .S. Wang
• Format: Others
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/47850328765529014622

碩士 === 長庚大學 === 物理治療學系 === 98 === Background and Purpose: Bone marrow-derived, circulating endothelial progenitor cells (EPC) is contributing to the maintenance of endothelial function and organ perfusion by mechanisms ranging from endothelial repair to postnatal angiogenesis and vasculogenesis. Although exercise or hypoxia has been observed to modulate EPC number in blood, the effect of exercise combined with hypoxia on the redistribution of circulating EPC subsets remains unclear. This study investigates how hypoxic exercise influences the mobilization of EPC subsets into the peripheral blood compartment. Methods: Forty-one sedentary healthy men were participated in the study, who were randomly distributed to hypoxic exercise group (60%VO2max exercise intensity for 40 min under 15%O2 in air on a bicycle ergometer 5days per week, total training 25 times) or normoxia group (under 21%O2 in air). Acute severity hypoxia exercise testing was performed at pre and post chronic exercise training (60%VO2max exercise intensity for 30 min under 12%O2 in air). At rest and immediately after severity hypoxia exercise, total of stem cells (SC, CD34+ cells) and overall the cell of associated with angiogenesis (CD34+/KDR+ cells), hematopoietic stem cells (HSC, CD34+/KDR+/CD117+ cells), endothelial progenitor cells (EPC, CD34+/KDR+/CD133+ cells), circulation endothelial precursor cells (CEP, CD34+/KDR+/CD133- cells), circulation endothelial cells (CEC, CD34+/KDR+/CD31+ cells), and shedding endothelial cells from vessels (SEC, KDR+/CD31+/phosphotidylserine exposed cells) were measured by three-color flow cytometry. Subsequently, we measured EPCs and subtypes cell proliferation ability by cell culture. Results: Exercise training improved cardiopulmonary fitness in normoxia and hypoxia groups. In blood analysis, acute hypoxia exercise testing could improve lymphocyte, stem cells, CD34 with KDR double positive cells, EPCs and CEPs in the first time. Through five weeks training, normoxia exercise increased the count of EPCs in peripheral blood compartment and hypoxia exercise significantly increased the number of CEP in the blood. Moreover, the amounts of SC, EPC and CEP in blood and EPC proliferation rate were significantly higher followed by normoxia exercise training. Additionally, hypoxia exercise improved more capability of resistance severely hypoxia. Conclusion: Hypoxic exercise markedly induced stem cell differentiation to the functional CEPs into peripheral blood, but that decreased count of EPC colony and proliferation rate by oxidation stress. Clinic Application and Future Research: This study clarify the relationships between hypoxic and normoxia exercise modulated redistribution of hematopoietic progenitor cells. In future, require more research relevant to EPC differentiation and proliferation capacity and improve angiogenesis ability in vivo by physical therapy method. We expect to provide a safe and effective strategy of physical therapy for patients with endothelial dysfunction.