Effect of acute hypoxia  on CXCR4 gene expression in C57BL/6 mouse bone marrow-derived mesenchymal stem cells

Kadivar, Mehdi; Alijani, Najva; Farahmandfar, Maryam; Rahmati, Saman; Ghahhari, Nastaran Mohammadi; Mahdian, Reza

Effect of acute hypoxia on CXCR4 gene expression in C57BL/6 mouse bone marrow-derived mesenchymal stem cells

Authors

¹ Department of Biochemistry, Pasteur Institute of Iran, Tehran, Iran

² Department of Neuroscience, School of Advanced Medical Technologies, Tehran University of Medical Sciences, Tehran, Iran

³ Department of Molecular Medicine, Pasteur Institute of Iran, Tehran, Iran

Abstract

Background: One of the most important stimuli in stem cell biology is oxygen. Chemokine receptor 4 (CXCR4) plays a crucial role in the migration and homing of stem cells. In this study, mesenchymal stem cells (MSCs) were exposed to 1% oxygen to investigate the effect of acute hypoxia on CXCR4 gene expression.
Materials and Methods: MSCs were isolated from C57BL/6 mouse bone marrow and were identified and expanded in normoxic culture. Cells were incubated at 37°C under 1% hypoxic conditions for periods of 4, 8, 16, 24, and 48 h. After hypoxia preconditioning, the cells were placed in normoxic condition for 8 h to achieve cellular hypoxia-reoxygenation. To assess the level of CXC R4 gene expression, real-time quantitative reverse transcription-polymerase chain reaction was carried out for each group.
Results: Data from statistical analysis illustrated that exposure of MSCs to acute hypoxic condition down-regulates CXCR4 expression with the maximum under-expression observed in 4 h (0.91 ± 0.107) and 8 h (50 ± 2.98) groups. Moreover, the relative gene expression of CXCR4 was decreased after hypoxia-reoxygenation by more than 80% in 4 h (0.136 ± 0.018) and 24 h (12.77 ± 0.707) groups.
Conclusion: The results suggest that CXCR4 expression in MSCs decreases upon acute hypoxic stress. Furthermore, hypoxia-reoxygenated MSCs showed decreased expression of CXCR4, compared to cells subjected to acute hypoxia. This difference could have resulted from the cells being compatible with low oxygen metabolism. In summary, before the therapeutic application of MSCs, it should be regarded as a necessity to optimize the oxygen concentration in these cells, as it is a critical factor in modulating CXCR4 expression.

Keywords

References

1.	Fan J, Varshney RR, Ren L, Cai D, Wang DA. Synovium-derived mesenchymal stem cells: A new cell source for musculoskeletal regeneration. Tissue Eng Part B Rev 2009;15:75-86.
2.	Hung SC, Pochampally RR, Hsu SC, Sanchez C, Chen SC, Spees J, et al. Short-term exposure of multipotent stromal cells to low oxygen increases their expression of CX3CR1 and CXCR4 and their engraftment in vivo. PLoS One 2007;2:e416.
3.	Ohnishi S, Yasuda T, Kitamura S, Nagaya N. Effect of hypoxia on gene expression of bone marrow-derived mesenchymal stem cells and mononuclear cells. Stem Cells 2007;25:1166-77.
4.	Sordi V, Malosio ML, Marchesi F, Mercalli A, Melzi R, Giordano T, et al. Bone marrow mesenchymal stem cells express a restricted set of functionally active chemokine receptors capable of promoting migration to pancreatic islets. Blood 2005;106:419-27.
5.	Bobis S, Jarocha D, Majka M. Mesenchymal stem cells: Characteristics and clinical applications. Folia Histochem Cytobiol 2006;44:215-30.
6.	Kyriakou C, Rabin N, Pizzey A, Nathwani A, Yong K. Factors that influence short-term homing of human bone marrow-derived mesenchymal stem cells in a xenogeneic animal model. Haematologica 2008;93:1457-65.
7.	Potapova IA, Brink PR, Cohen IS, Doronin SV. Culturing of human mesenchymal stem cells as three-dimensional aggregates induces functional expression of CXCR4 that regulates adhesion to endothelial cells. J Biol Chem 2008;283:13100-7.
8.	Ma T, Grayson WL, Fröhlich M, Vunjak-Novakovic G. Hypoxia and stem cell-based engineering of mesenchymal tissues. Biotechnol Prog 2009;25:32-42.
9.	Fehrer C, Brunauer R, Laschober G, Unterluggauer H, Reitinger S, Kloss F, et al. Reduced oxygen tension attenuates differentiation capacity of human mesenchymal stem cells and prolongs their lifespan. Aging Cell 2007;6:745-57.
10.	Fink T, Abildtrup L, Fogd K, Abdallah BM, Kassem M, Ebbesen P,et al. Induction of adipocyte-like phenotype in human mesenchymal stem cells by hypoxia. Stem Cells 2004;22:1346-55.
11.	Nekanti U, Dastidar S, Venugopal P, Totey S, Ta M. Increased proliferation and analysis of differential gene expression in human Wharton's jelly-derived mesenchymal stromal cells under hypoxia. Int J Biol Sci 2010;6:499-512.
12.	Valorani MG, Germani A, Otto WR, Harper L, Biddle A, Khoo CP, et al. Hypoxia increases Sca-1/CD44 co-expression in murine mesenchymal stem cells and enhances their adipogenic differentiation potential. Cell Tissue Res 2010;341:111-20.
13.	Rosová I, Dao M, Capoccia B, Link D, Nolta JA. Hypoxic preconditioning results in increased motility and improved therapeutic potential of human mesenchymal stem cells. Stem Cells 2008;26:2173-82.
14.	Tang YL, Zhu W, Cheng M, Chen L, Zhang J, Sun T, et al. Hypoxic preconditioning enhances the benefit of cardiac progenitor cell therapy for treatment of myocardial infarction by inducing CXCR4 expression. Circ Res 2009;104:1209-16.
15.	Schioppa T, Uranchimeg B, Saccani A, Biswas SK, Doni A, Rapisarda A, et al. Regulation of the chemokine receptor CXCR4 by hypoxia. J Exp Med 2003;198:1391-402.
16.	Povan E, Tosello V, Indraccolo S, Masiero M, Persano L, Esposito G, et al. Differential regulation of hypoxia-induced CXCR4 triggering during B-cell development and lymphomagenesis. Cancer Res 2007;67:8605-14.
17.	Lavrentieva A, Majore I, Kasper C, Hass R. Effects of hypoxic culture conditions on umbilical cord-derived human mesenchymal stem cells. Cell Commun Signal 2010;8:18.
18.	Mylotte LA, Duffy AM, Murphy M, O'Brien T, Samali A, Barry F, et al. Metabolic flexibility permits mesenchymal stem cell survival in an ischemic environment. Stem Cells 2008;26:1325-36.
19.	Kaluz S, Kaluzová M, Stanbridge EJ. Regulation of gene expression by hypoxia: Integration of the HIF-transduced hypoxic signal at the hypoxia-responsive element. Clin Chim Acta 2008;395:6-13.
20.	Berchner-Pfannschmidt U, Frede S, Wotzlaw C, Fandrey J. Imaging of the hypoxia-inducible factor pathway: Insights into oxygen sensing. Eur Respir J 2008;32:210-7.
21.	Ratajczak MZ, Zuba-Surma E, Kucia M, Reca R, Wojakowski W, Ratajczak J. The pleiotropic effects of the SDF-1-CXCR4 axis in organogenesis, regeneration and tumorigenesis. Leukemia 2006;20:1915-24.
22.	Zhang Y, Wittner M, Bouamar H, Jarrier P, Vainchenker W, Louache F. Identification of CXCR4 as a new nitric oxide-regulated gene in human CD34+cells. Stem Cells 2007;25:211-9.
23.	Maroni P, Bendinelli P, Matteucci E, Desiderio MA. HGF induces CXCR4 and CXCL12-mediated tumor invasion through Ets1 and NF-kappaB. Carcinogenesis 2007;28:267-79.

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