title: The role of SDF-1α/Rac pathway in the regulation of endothelial progenitor cell polarity; homing and expression of Rac1, Rac2 during endothelial repair.
abstract: The Stromal cell-derived factor-1 (SDF-1)/CXC chemokine receptor 4 (CXCR4) system is considered to be of great importance in diseases involving cardiogenesis and angiogenesis. The SDF-1α-RAC signaling pathway plays a pivotal role in a cell's polarity and serves to activate cell morphology variation and to control the direction of migration. We aimed to study whether the polarity of endothelial progenitor cells (EPCs) is changed by the induction of the SDF-1α-RAC signaling pathway, to investigate the mechanism of the effect of polarity on the homing action of EPCs, and to explore the gene and protein expression of Rac1/2 during endothelial repair. We measured the EPC characteristics of polarity induced by various final concentrations of SDF-1α; our observations included morphology variation, migration direction, and excursion. Of the dynamic variation and cytoskeleton rearrangement of EPCs induced by different final concentrations of SDF-1α, the most obvious variation was exhibited at the SDF-1α concentration of 200 ng/ml. Obvious polarity variations were also found in the EPCs and signal receptors induced by the SDF-1α concentration of 200 ng/ml. The Western blot analysis of Rac1 and Rac2 showed that the addition of AMD 3100 significantly inhibited the expression of Rac. The SDF-1α pathway potentially regulates the expression of Rac1/2. The actual excursion vector and the direction of the migration of EPCs induced by SDF-1α follows polarity, thus indicating the importance of further exploration regarding the homing induction of EPCs.
authors.affiliation: Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai 200032, People's Republic of China.
authors.forename: Li
authors.initials: L
authors.lastname: Shen
authors.forename: Yongxing
authors.initials: Y
authors.lastname: Gao
authors.forename: Juying
authors.initials: J
authors.lastname: Qian
authors.forename: Yizhe
authors.initials: Y
authors.lastname: Wu
authors.forename: Mingming
authors.initials: M
authors.lastname: Zhou
authors.forename: Aijun
authors.initials: A
authors.lastname: Sun
authors.forename: Yunzeng
authors.initials: Y
authors.lastname: Zou
authors.forename: Junbo
authors.initials: J
authors.lastname: Ge
mesh_terms: D001596:Benzylamines; D015815:Cell Adhesion Molecules / Q000378:metabolism; D002465:Cell Movement; D016764:Cell Polarity; D048430:Cell Shape; D002478:Cells, Cultured; D054377:Chemokine CXCL12 / Q000502:physiology*; D000080027:Cyclams; D003599:Cytoskeleton / Q000378:metabolism; D042783:Endothelial Cells / Q000378:metabolism / Q000502:physiology; D005312:Fetal Blood / Q000166:cytology; D005786:Gene Expression Regulation; D006571:Heterocyclic Compounds / Q000494:pharmacology; D006801:Humans; D019707:Receptors, Chemokine / Q000037:antagonists & inhibitors / Q000378:metabolism; D015398:Signal Transduction; D013234:Stem Cells / Q000378:metabolism / Q000502:physiology*; D014158:Transcription, Genetic; D014945:Wound Healing; D020744:rac GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D020830:rac1 GTP-Binding Protein / Q000235:genetics / Q000378:metabolism*; D000097766:RAC2 GTP-Binding Protein
chemical_list: D001596:Benzylamines; D015815:Cell Adhesion Molecules; D054377:Chemokine CXCL12; D000080027:Cyclams; D006571:Heterocyclic Compounds; D019707:Receptors, Chemokine; D020744:rac GTP-Binding Proteins; D020830:rac1 GTP-Binding Protein; D000097766:RAC2 GTP-Binding Protein; C107953:RAC1 protein, human; C088327:plerixafor