Exercise promotes mobilization of hematopoietic progenitor cells involved in repair of sciatic nerve crush injury

• Main Authors: Jia-ming Li, 李家銘
• Other Authors: Ming-fu Wang
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/18566703275639744497

碩士 === 靜宜大學 === 食品營養研究所 === 99 === Background: Hematopoietic progenitor cells involved in the process of peripheral nerve regeneration occurs mostly through deposits of CD 34+ cells. Treadmill exercise either with various intensity or duration increases axon regeneration and sprouting, but the effect of bone marrow mobilization after treadmill exercise has not been determined. Material and Methods: Peripheral nerve injury was induced in Sprague-Dawley rats by crushing left sciatic nerve using a vessel clamp. The animals were categorized into two groups either with or without treadmill exercise (20 M/min for 60min per day for 7 days). Cytospin and flow cytometry were used to determine bone marrow progenitor cell density and distribution. Neurobehavior, electrophysiological study, and regeneration marker expression were conducted at one and three weeks after exercise. The accumulation of hematopoietic progenitor cells, immune cells and angiogenesis factors in injured nerves were determined. Results: Treadmill exercise significantly promoted nerve regeneration. Increased Schwann cell proliferation, escalated neurofilament, and decreased Schwann cell apoptosis were observed 7 days after treadmill exercise. Elevated expression of S-100 and Luxol fast blue as well as decreased numbers of vacuoles were identified in crushed nerves after exercise. Significantly increased numbers of mononuclear cells, particularly CD34+ cells, were induced in bone marrow after treadmill exercise. Deposits of CD34+ cells in crushed nerves paralleled the elevated expressions of Von-Willebrand, Isolectin B4, and VEGF. Conclusion: Bone marrow hematopoietic progenitor cells especially CD34+ cells can be mobilized by low intensity treadmill exercise and this effect paralleled significant expression of angiogenesis factors and increased motor function.