Peng Yu1,2,3, Zhifei Zhang1,2,3, Shengjie Li1,2,3, Xiaolong Wen1,2,3, Wei Quan1,2,3, Qilong Tian1,2,3, Jieli Chen4, Jianning Zhang1,2,3, Rongcai Jiang1,2,3. 1. Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, 300052, China. 2. Tianjin Neurological Institute, Tianjin, 300052, China. 3. Key Laboratory of Post-Neurotrauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education and Tianjin City, Tianjin, 300052, China. 4. Department of Neurology, Henry Ford Hospital, Detroit, Michigan, 48202, USA.
Abstract
OBJECTIVES: Progesterone treatment can effectively increase levels of circulating endothelial progenitor cells (EPCs) and improve neurological functional outcome in a traumatic brain injury (TBI) rat model. However, the mechanisms of progesterone's effects on EPC viability remain elusive. The CXCL12/CXCR4 (CXC chemokine ligand 12/CXC chemokine receptor 4) signalling pathway regulates cell proliferation; we hypothesize that it mediates progesterone-induced EPC viability. MATERIALS AND METHODS: EPCs were isolated from bone marrow-derived mononuclear cells (BM-MNCs) and treated with progesterone (5, 10 and 100 nm). MTS assay was used to investigate EPC viability. Protein expression was examined by Western blotting, ELISA assay and flow cytometry. Cell membrane and cytoplasm proteins were extracted with membrane and cytoplasm protein extraction kits. CXCR4 antagonist (AMD3100) and phosphatidylinositol 3-kinases (PI3K) antagonist (LY294002) were used to characterize underlying mechanisms. RESULTS: Progesterone-induced EPC viability was time- and dose-dependent. Administration of progesterone facilitated EPC viability and increased expression of CXCL12 and phosphorylated Akt (also known as protein kinase B, pAkt) activity (P < 0.05). Progesterone did not regulate CXCR4 protein expression in cultured EPC membranes or cytoplasm. However, progesterone-induced EPC viability was significantly attenuated by AMD3100 or LY294002. Inhibition of the signalling pathway with AMD3100 and LY294002 subsequently reduced progesterone-induced CXCL12/CXCR4/PI3K/pAkt signalling activity. CONCLUSIONS: The CXCL12/CXCR4/PI3K/pAkt signalling pathway increased progesterone-induced EPC viability.
OBJECTIVES:Progesterone treatment can effectively increase levels of circulating endothelial progenitor cells (EPCs) and improve neurological functional outcome in a traumatic brain injury (TBI) rat model. However, the mechanisms of progesterone's effects on EPC viability remain elusive. The CXCL12/CXCR4 (CXC chemokine ligand 12/CXC chemokine receptor 4) signalling pathway regulates cell proliferation; we hypothesize that it mediates progesterone-induced EPC viability. MATERIALS AND METHODS: EPCs were isolated from bone marrow-derived mononuclear cells (BM-MNCs) and treated with progesterone (5, 10 and 100 nm). MTS assay was used to investigate EPC viability. Protein expression was examined by Western blotting, ELISA assay and flow cytometry. Cell membrane and cytoplasm proteins were extracted with membrane and cytoplasm protein extraction kits. CXCR4 antagonist (AMD3100) and phosphatidylinositol 3-kinases (PI3K) antagonist (LY294002) were used to characterize underlying mechanisms. RESULTS:Progesterone-induced EPC viability was time- and dose-dependent. Administration of progesterone facilitated EPC viability and increased expression of CXCL12 and phosphorylated Akt (also known as protein kinase B, pAkt) activity (P < 0.05). Progesterone did not regulate CXCR4 protein expression in cultured EPC membranes or cytoplasm. However, progesterone-induced EPC viability was significantly attenuated by AMD3100 or LY294002. Inhibition of the signalling pathway with AMD3100 and LY294002 subsequently reduced progesterone-induced CXCL12/CXCR4/PI3K/pAkt signalling activity. CONCLUSIONS: The CXCL12/CXCR4/PI3K/pAkt signalling pathway increased progesterone-induced EPC viability.
Authors: Akira Orimo; Piyush B Gupta; Dennis C Sgroi; Fernando Arenzana-Seisdedos; Thierry Delaunay; Rizwan Naeem; Vincent J Carey; Andrea L Richardson; Robert A Weinberg Journal: Cell Date: 2005-05-06 Impact factor: 41.582
Authors: Magda Kucia; Kacper Jankowski; Ryan Reca; Marcin Wysoczynski; Laura Bandura; Daniel J Allendorf; Jin Zhang; Janina Ratajczak; Mariusz Z Ratajczak Journal: J Mol Histol Date: 2004-03 Impact factor: 2.611