Osteoporotic effects observed after osteoporosis induction in the rat by combining ovariectomy (OVX) either with a defined calcium-deficient diet (OVX + Diet) or by administration of a glucocorticoid (dexamethasone) (OVX + Steroid) mimic the skeletal effects observed in humans affected by osteoporosis. In the present investigation rat MSCs have been characterized in vitro after osteoporosis has been induced for twelve weeks in rats by means of OVX + Diet ( ) and OVX + Steroid ( ). Sham-operated animals ( ) served as controls. MSCs were harvested from humerus and iliac crest and were cultured in standard medium and in osteogenic differentiation medium for studying the proliferation, migration, and differentiation capacity of the cells. Expression of CD90, CD105, runx2, osteocalcin (OC), and bone sialoprotein (BSP) was performed by using qrtPCR. Calcium deposits developed in the course of osteogenic differentiation were measured by using Pentra 400 Axon Lab. Taken together, the present results showed that osteoporosis induction leads to MSC in a state of senescence: proliferation and migration rates of the cells were diminished pointing to self-renewal deficiency and impaired motility of rat MSC in contrast to controls. However, the osteogenic differentiation capacity was increased after osteoporosis induction with OVX + Diet and OVX + Steroid. 1. Introduction By definition of the Consensus Development Conference osteoporosis is a disease characterized by low bone mass and microarchitectural deterioration of bone tissue leading to enhanced bone fragility and a consequent increase in fracture risk (European foundation for osteoporosis 1991). As this disease is restricted to humans [1], there is a great need for animal models in order to validate new therapeutic approaches such as drugs or prosthetic devices. The most commonly used animal model for osteoporosis is so far the ovariectomized rat [1–3]. In a previous study we have shown that enhanced osteoporotic effects ( scores below ？2,5, reduced bone mineral density and bone mineral content measured by means of Dual Energy X-ray Absorptiometry, DEXA) could be seen in rats by combining ovariectomy with calcium, phosphorus, vitamin c, and vitamin D2/D3 deficiency over a period of 12 weeks [4]. However, little information is available about mesenchymal stem cells (MSCs) residing in the bone marrow of the “osteoporotic” rats. MSCs are multipotential precursor cells that can differentiate into various cell types such as osteoblasts, chondrocytes, and adipocytes [5]. Due to this differentiation potential
References
[1]
A. S. Turner, “Animal models of osteoporosis—necessity and limitations,” European Cells and Materials, vol. 1, pp. 66–81, 2001.
[2]
H. M. Frost and W. S. S. Jee, “On the rat model of human osteopenias and osteoporoses,” Bone and Mineral, vol. 18, no. 3, pp. 227–236, 1992.
[3]
P. P. Lelovas, T. T. Xanthos, S. E. Thorma, G. P. Lyritis, and I. A. Dontas, “The laboratory rat as an animal model for osteoporosis research,” Comparative Medicine, vol. 58, no. 5, pp. 424–430, 2008.
[4]
C. Heiss, P. Govindarajan, G. Schlewitz, et al., “Induction of osteoporosis with its influence on osteoporotic determinants and their interrelationships in rats by DEXA,” Medical Science Monitor, vol. 18, pp. BR199–BR207, 2012.
[5]
M. Dominici, K. Le Blanc, I. Mueller et al., “Minimal criteria for defining multipotent mesenchymal stromal cells. The International Society for Cellular Therapy position statement,” Cytotherapy, vol. 8, no. 4, pp. 315–317, 2006.
[6]
K. Nohroudi, S. Arnhold, T. Berhorn, K. Addicks, M. Hoehn, and U. Himmelreich, “In vivo MRI stem cell tracking requires balancing of detection limit and cell viability,” Cell Transplantation, vol. 19, no. 4, pp. 431–441, 2010.
[7]
F. Ayaloglu-Butun, E. Terzioglu-Kara, Z. Tokcaer-Keskin, and K. C. Akcali, “The effect of estrogen on bone marrow-derived rat mesenchymal stem cell maintenance: inhibiting apoptosis through the expression of Bcl-xL and Bcl-2,” Stem Cell Reviews and Reports, vol. 8, pp. 393–401, 2012.
[8]
D. Chanda, S. Kumar, and S. Ponnazhagan, “Therapeutic potential of adult bone marrow-derived mesenchymal stem cells in diseases of the skeleton,” Journal of Cellular Biochemistry, vol. 111, no. 2, pp. 249–257, 2010.
[9]
A. Wilson, L. A. Shehadeh, H. Yu, and K. A. Webster, “Age-related molecular genetic changes of murine bone marrow mesenchymal stem cells,” BMC Genomics, vol. 11, no. 1, article 229, 2010.
[10]
J. P. Rodriguez, S. Garat, H. Gajardo, et al., “Abnormal osteogenesis in osteoporotic patients is reflected by altered mesenchymal stem cells dynamics,” Journal of Cellular Biochemistry, vol. 75, pp. 414–423, 1999.
[11]
J. Justesen, K. Stenderup, E. F. Eriksen, and M. Kassem, “Maintenance of osteoblastic and adipocytic differentiation potential with age and osteoporosis in human marrow stromal cell cultures,” Calcified Tissue International, vol. 71, no. 1, pp. 36–44, 2002.
[12]
J. P. Rodriguez, L. Montecinos, S. Rios, et al., “Mesenchymal stem cells from osteoporotic patients produce a type I collagen-deficient extracellular matrix favoring adipogenic differentiation,” Journal of Cellular Biochemistry, vol. 79, pp. 557–565, 2000.
[13]
D. C. Colter, I. Sekiya, and D. J. Prockop, “Identification of a subpopulation of rapidly self-renewing and multipotential adult stem cells in colonies of human marrow stromal cells,” Proceedings of the National Academy of Sciences of the United States of America, vol. 98, no. 14, pp. 7841–7845, 2001.
[14]
R. Tuli, S. Tuli, S. Nandi et al., “Characterization of multipotential mesenchymal progenitor cells derived from human trabecular bone,” Stem Cells, vol. 21, no. 6, pp. 681–693, 2003.
[15]
F. Z. Asumda and P. B. Chase, “Age-related changes in rat bone-marrow mesenchymal stem cell plasticity,” BMC Cell Biology, vol. 12, article 44, 2011.
[16]
M. Bonyadi, S. D. Waldman, D. Liu, J. E. Aubin, M. D. Grynpas, and W. L. Stanford, “Mesenchymal progenitor self-renewal deficiency leads to age-dependent osteoporosis in Sca-1/Ly-6A null mice,” Proceedings of the National Academy of Sciences of the United States of America, vol. 100, no. 10, pp. 5840–5845, 2003.
[17]
L. Moroni and P. M. Fornasari, “Human mesenchymal stem cells: a bank perspective on the isolation, characterization and potential of alternative sources for the regeneration of musculoskeletal tissues,” Journal of Cellular Physiology, vol. 228, pp. 680–687, 2013.
[18]
P. Benisch, T. Schilling, L. Klein-Hitpass, et al., “The transcriptional profile of mesenchymal stem cell populations in primary osteoporosis is distinct and shows overexpression of osteogenic inhibitors,” PLoS One, vol. 7, article e45142, 2012.
