摘要
中长期空间飞行导致机体发生的骨丢失等航天医学问题,已经成为人类向更深、更远、更高的外层空间探索的制约因素之一。目前空间飞行采取的运动锻炼、药物预防和营养补充都不能有效防止骨丢失的发生发展;为了确保航天员在未来长期飞行任务中健康、高效工作,需要在细胞分子水平阐明空间骨丢失的发生机制;发展基于细胞分子本质认识的有效对抗防护措施。这是载人航天发展的迫切和必然要求。
空间骨丢失是航天员在太空易患疾病的首要风险因素,其发生的主要原因是骨形成减少。失重不但影响成骨细胞的分化进程,还影响其分化起始。启动和调控成骨细胞分化的关键转录因子Cbfa1,也是一个力信号传导的靶分子。骨相关细胞因子参与了成骨细胞的增殖、分化调节,包括对Cbfa1活性的调节。失重影响多个骨相关细胞因子的表达和信号传导。因此,阐明失重条件下骨相关细胞因子在骨丢失中的作用,对骨丢失机制的阐明和发展有效对抗防护措施具有重要意义。
前期研究表明失重条件下,骨相关细胞因子对BMSC和前成骨细胞的增殖、分化的促进作用减弱,使成骨细胞数量减少和活性下降,导致骨形成减弱,进而发生骨质丢失。因此,本研究构建了能用报告基因反映Cbfa1活性的成骨细胞模型和IGF-I选择性剪接模型;采用细胞回转、大鼠尾吊和液流剪切等力刺激模型;研究骨相关细胞因子对BMSC增殖、对前成骨细胞Cbfa1活性的影响及可能的机制,观察尾吊大鼠骨骼组织中IGF-I基因表达和调控变化;旨在探讨骨相关细胞因子在失重条件下表达、调控和作用的变化,为阐明空间骨丢失的细胞分子机制提供科学依据。
实验方法:(1)采用基于红细胞裂解的全骨髓培养法分离培养BMSC,通过亚甲基蓝染色和流式细胞仪检测,观察回转对BMSC增殖、细胞周期及对细胞因子促增值效应的影响;采用免疫荧光染色、RT-PCR、Western、基因芯片方法,研究回转对BMSC微丝骨架、ERK1/2活性、成骨向分化、基因表达谱的影响。(2)通过载体构建和稳定转染,构建用报告基因反映成骨细胞Cbfa1活性的模型,通过EGFP的荧光强度半定量分析或Luc酶活性分析,研究不同重力、VD3和BMP2对Cbfa1活性的影响以及回转条件下Cbfa1对VD3和BMP2的响应特征;通过双向CO-IP,观察回转和超重条件下VDR与Cbfa1相互作用的变化;采用微丝骨架破坏剂CB和稳定剂JAS,研究细胞微丝骨架在BMP2诱导Cbfa1活性中的作用。(3)利用细胞回转和大鼠尾吊模型,采用RT-qPCR方法,研究回转和不同尾吊时间对成骨细胞、骨骼组织IGF-I选择性剪接异构体表达的影响;通过PCR扩增和基因亚克隆,构建了4个含IGF-I外显子5及两侧不同长度内含子的选择性剪接载体,分别稳定转染到MC3T3-E1中,建立IGF-I选择性剪接模型;利用流体剪切实验系统;观察1Pa剪切力刺激1小时对IGF-I选择性剪接的影响。
结果发现:(1)回转破坏细胞微丝骨架,并具有时间依赖性;使G1/G0期的细胞数量增加,由86.6%增加到91.4%,从而抑制了BMSC增殖;降低了信号分子ERK1/2活性和细胞因子IGF-I、EGF和bFGF对BMSC的促增殖作用,促增殖效应分别由15.5%、16.3%和26.9%下降到10.5%、10.3%和19.6%;抑制了BMSC的成骨向分化潜能;基因表达谱和功能聚类分析表明与细胞周期、微丝骨架、成骨细胞分化相关基因的表达发生了改变,且表达升高的负调控基因占多数。(2)建立了能用EGFP或Luc报告基因反映Cbfa1活性的成骨细胞模型;发现回转抑制Cbfa1活性,而超重能提高Cbfa1活性;VD3和BMP2均可提高Cbfa1的活性,但回转可降低VD3和BMP2对Cbfa1活性的刺激作用,回转条件下VD3和BMP2诱导的Cbfa1活性增加分别由79%和18%下降到43%和14%,同时VD3受体VDR与Cbfa1之间的相互作用受到抑制;回转可破坏MG63的微丝骨架;低浓度微丝骨架破坏剂CB(0.5nmol/L)降低了BMP2对Cbfa1活性的增强作用,而微丝骨架稳定剂JAS在一定程度上能保护BMP2对Cbfa1活性的刺激作用。(3)大鼠尾吊降低骨骼组织IGF-IEa和MGF的表达,且具有时间依赖性;使血清中IGF-I水平下降。筛选出了4个分别稳定转染含外显子5及两侧不同长度内含子的IGF-I选择性剪接载体的细胞株;1Pa流体力能显著提高稳定转染p5341选择性剪接载体细胞株的MGF-EGFP表达,而对其他细胞株没有影响。
结论:回转抑制了BMSC的增殖和骨向分化潜能,降低其对细胞因子IGF-I、EGF和bFGF的响应性。回转通过削弱VDR与Cbfa1之间的相互作用,降低了VD3对Cbfa1活性的刺激作用;细胞微丝骨架参与BMP2对Cbfa1活性的刺激作用,而回转诱导的微丝骨架解聚可能是Cbfa1对BMP2的响应性下降的重要原因;大鼠尾吊导致骨骼组织IGF-IEa和MGF表达下降和血清IGF-I水平降低;失重可以影响IGF-I选择性剪接。剪切力可通过IGF-I内含子上的元件调控其选择性剪接。这些研究为阐明空间骨丢失的细胞分子机制提供重要的科学依据。
Space medicine problem induced by long-term spaceflight, especially bone loss, has been one of restrictfactors of manexploring to the deeper, further and higher outer space. Exercise, drug and nutritional supplements taken by astronaut at present spaceflight, can’t effectively prevent bone loss occurrence. To assurance the health and effective performance of astronaut during future long-term spaceflight mission, it was required to clarify the mechanism of bone loss in space and develop effective countermeasure against bone loss based on the cellular and molecular intrinsic understanding of bone loss, which are also the urgent and necessary requirement of the developing manned space.
Bone loss in space is primary risk factor of the susceptible disease for astronaut during spaceflight and mainly due to the decreased bone formation. Weightlessness not only affects the differentiation process of osteoblast, also influences the osteogenic initiation from osteogentior cell. Cbfa1 is a key transcription factor for the initiation and regulation of osteoblast differentiation, and a target for mechanic signaling. Bone-related cytokines participate the regulation of osteoblast proliferation and differentiation, including Cbfa1 activity. Moreover, weightlessness affects the expression and signal transduction of bone related cytokine. It is important to clarify the function of bone related cytokines to bone loss in space under weightlessness condition which also have significance for the mechanism clarification and countermeasure development against bone loss in space.
Previous studies suggest that the decreased proliferation and differentiation responsiveness of BMSC and preosteoblast to bone-related cytokines stimulation attenuate the number and activity of osteoblast, which induce bone formation decrease and bone loss ultimately under weightlessness condition. In present study, we constructed osteoblast modeling in which Cbfa1 activity can be reflected by reporter and IGF-I alternative splicing model;Cell clinorotation, rat hindlimb suspension and flow shear stress were used to investigate the effects of bone-related cytokines on BMSC proliferation, Cbfa1 activity of preosteoblast and their mechanism, study the expression and regulation changes of rat bone IGF-I gene after hindlimb suspension. We aim to explore the changed of bone-related cytokine in expression, regulation and function under weightlessness condition. These studies results will provide new science evidence for clarifying the cellular and molecular mechanism of bone loss in space.
Methods: (1) BMSCs were isolated using whole bone marrow culture method based on red cell lysis. The proliferation, cell cycle and promotive effects of cytokines under clinorotation condition were investigated by methylene blue staining and flow cytometry examination. Effects of clinorotation on microfilament cytoskeleton, ERK1/2 activity, osteogenic differentiation and expression profile were studied using immunofluorescence staining, RT-PCR, Western blot, gene chip etc. (2) Osteoblast models were developed by vector construction and stable transfection, in which Cbfa1 activity can be reflected by reporter activity. The effects of different gravity, VD3 and BMP2 on Cbfa1 activity and the responsiveness character of Cbfa1 to VD3 and BMP2 under clinorotation were investigated using these models by semi-quantitative analysis of EGFP fluorescence intensity or luciferase activity. Using bidirectional CO-IP, the interaction change between VDR and Cbfa1 was studied under clinorotation or hypergravity. F-actin inhibitor (CB) or stabilizer (Jas) was used to investigate the function of cytoskeleton on promotive effect of BMP2 to Cbfa1 activity. (3) Real time RT-PCR was used to examined the expression alternation of IGF-I alternative splicing isoforms under clinorotation for osteoblast or hindlimb suspension for bone tissue. We constructed 4 IGF-I alternative splicing vectors by PCR amplification and subclone, which were stably transfected into MC3T3-E1 respectively and IGF-I alternative splicing models were developed. Experiment system of Flow shear were developed to investigate the effects of FSS with 1Pa for 1h on IGF-I alternative splicing.
Results:(1) Clinorotation time-dependently disrupted the microfilament cytoskeleton, made more cells arrest in G1/G0 phase of cell cycle from 86.6% to 91.4%; and inhibited proliferation of BMSC. Clinorotation also decreased the activity of ERK1/2 and the promotive effects of IGF-I, EGF and bFGF to BMSC proliferation, from 15.5%, 16.3%, 26.9% to 10.5%, 10.3%, 19.6% respectively; inhibited the osteogenic differentiation potency of BMSC. Microarray and cluster analysis suggested that the expression of some genes related to the terms of cell cycle, microfilament, osteogenic differentiation were changed, especially more upregulated negative regulation gene. (2) Osteoblast models were developed in which Cbfa1 activity can be reflected by fluorescence intensity of EGFP or Luciferase activity. Clinorotation significantly inhibited the Cbfa1 activity, but hypergravity promoted it. Both VD3 and BMP2 increased the activity of Cbfa1, but clinorotation inhibited the stimulation effects of VD3 and BMP2 to Cbfa1 activity. The increased degree of Cbfa1 activity decreased from 79%, 18% to 43%, 14% respectively. Clinorotation attenuated the interaction between VDR, VD3 receptor, and Cbfa1, also disrupted the F-actin cytoskeleton. Low concentration of cytochalasin B (0.5nmol/L), an inhibitor of F-actin, abolished the promotive effect of BMP2 to Cbfa1 activity. F-actin stabilizer (Jas) can protect, at some extent, the promotive effect of BMP2 to Cbfa1 activity under clinorotation condition. (3) Hindlimb suspension time-dependently decreased IGF-IEa and MGF mRNA level in bone tissue and IGF-I level in serum. Four cell strains which was stably transfected with alternative splicing vectors including different length intron locusing at exon 5 flank were selected and the expression of MGF-EGFP significantly increase in 5341 strain after subjected to 1Pa FSS treatment for 1h, but no changes were observed in other stable transfected cells.
Conclusion: clinorotation significantly inhibits the proliferation and osteogenic differentiation of BMSC, decreases the proliferation responsiveness to cytokine IGF-I, EGF and bFGF. Clinorotation also attenuates the interaction between VDR and Cbfa1 which maybe contribute the decreased responsiveness of Cbfa1 activity to VD3. Microfilament cytoskeleton participates the promotive effect of BMP2 to Cbfa1 activity and disruption of F-actin maybe contributes to the attenuated responsiveness of Cbfa1 activity to BMP2 under clinorotation. Hindlimb suspension affects the IGF-IEa and MGF expression in bone and IGF-I level in serum. Weightlessness can influence the alternative splicing of IGF-I. FSS can regulated the IGF-I alternative splicing via the intron elements. These results provide new scientific evidences for cellular molecular mechanisms of bone loss in space.
引文
1. Aubin JE. Advances in the osteoblast lineage. Biochem Cell Biol. 1998a, 76(6): 899-910.
2. Aubin JE. Bone stem cells. J Cell Biochem.. 1998b, 30-31(Suppl): 73-82.
3. Basso N, Bellows CG and Heersche JN. Effect of simulated weightlessness on osteoprogenitor cell number and proliferation in young and adult rats. Bone. 2005, 36(1): 173-183.
4. Bikle DD, Harris J, Halloran BP and Morey-Holton E. Altered skeletal pattern of gene expression in response to spaceflight and hindlimb elevation. Am J Physiol. 1994a, 267(6 Pt 1): E822-827.
5. Bikle DD, Harris J, Halloran BP and Morey-Holton ER. Skeletal unloading induces resistance to insulin-like growth factor I. J Bone Miner Res. 1994b, 9(11): 1789-1796.
6. Boonstra J. Growth factor-induced signal transduction in adherent mammalian cells is sensitive to gravity. FASEB J. 1999, 13(Suppl): S35-42.
7. Buravkova LB, Gershovich YG and Grigorev AI. Sensitivity of stromal precursor cells of different commitment to simulated microgravity. Dokl Biol Sci. 2010, 432: 237-240.
8. Buravkova LB, Romanov YA, Konstantinova NA, Buravkov SV, Gershovich YG and Grivennikov IA. Cultured stem cells are sensitive to gravity changes. Acta Astronautica. 2008, 63(5-6): 603-608.
9. Burger EH and Klein-Nulend J. Microgravity and bone cell mechanosensitivity. Bone. 1998, 22(5 Suppl): 127S-130S.
10. Burger EH and Klein-Nulend J. Mechanotransduction in bone--role of the lacuno-canalicular network. FASEB J. 1999, 13 Suppl: S101-112.
11. Caillot-Augusseau A, Lafage-Proust MH, Soler C, Pernod J, Dubois F and Alexandre C. Bone formation and resorption biological markers in cosmonauts during and after a 180-day space flight (Euromir 95). Clin Chem. 1998, 44(3): 578-585.
12. Carmeliet G and Bouillon R. The effect of microgravity on morphology and gene expression of osteoblasts in vitro. FASEB J. 1999, 13(Suppl): S129-134.
13. Carmeliet G, Nys G and Bouillon R. Microgravity reduces the differentiation of human osteoblastic MG-63 cells. J Bone Miner Res. 1997, 12(5): 786-794.
14. Carmeliet G, Nys G, Stockmans I and Bouillon R. Gene expression related to the differentiation of osteoblastic cells is altered by microgravity. Bone. 1998, 22(5Suppl): 139S-143S.
15. Cavanagh PR, Licata AA and Rice AJ. Exercise and pharmacological countermeasures for bone loss during long-duration space flight. Gravit Space Biol Bull. 2005, 18(2): 39-58.
16. Chen X, Xu H, Wan C, McCaigue M and Li G. Bioreactor expansion of human adult bone marrow-derived mesenchymal stem cells. Stem Cells. 2006, 24(9): 2052-2059.
17. Coenegrachts L, Stockmans I, Segers I, Bouillon R and Carmeliet G. The effect of microgravity on 1,25-dihydroxyvitamin D3 signalling in osteoblasts. Microgravity SCITEC. 2007, 19(5): 154-158.
18. Collet P, Uebelhart D, Vico L, Moro L, Hartmann D, Roth M and Alexandre C. Effects of 1- and 6-month spaceflight on bone mass and biochemistry in two humans. Bone. 1997, 20(6): 547-551.
19. Colvin GA, Lambert JF, Carlson JE, McAuliffe CI, Abedi M and Quesenberry PJ. Rhythmicity of engraftment and altered cell cycle kinetics of cytokine-cultured murine marrow in simulated microgravity compared with static cultures. In Vitro Cell Dev Biol Anim. 2002, 38(6): 343-351.
20. Cowin SC. On mechanosensation in bone under microgravity. Bone. 1998, 22(5 Suppl): 119S-125S.
21. Dai Z, Li Y, Ding B, Zhang X, Tan Y and Wan Y. Actin microfilaments participate in the regulation of the COL1A1 promoter activity in ROS17/2.8 cells under simulated microgravity. Adv Space Res. 2006, 38(6): 1159-1167.
22. Dai Z, Wu F, Yeung EW and Li Y. IGF-IEc expression, regulation and biological function in different tissues. Growth Horm IGF Res. 2010, 20(4): 275-281.
23. Dai Z, Wang R, Ling S, Wan Y and Li Y. Simulated microgravity inhibits the proliferation and osteogenesis of rat bone marrow mesenchymal stem cells. Cell Prolif. 2007, 40(5): 671-684.
24. Dalsky GP, Stocke KS, Ehsani AA, Slatopolsky E, Lee WC and Birge SJ, Jr. Weight-bearing exercise training and lumbar bone mineral content in postmenopausal women. Ann Intern Med. 1988, 108(6): 824-828.
25. de Groot RP, Rijken PJ, Boonstra J, Verkleij AJ, de Laat SW and Kruijer W. Epidermal growth factor-induced expression of c-fos is influenced by altered gravity conditions. Aviat Space Environ Med. 1991, 62(1): 37-40.
26. Deng M, Zhang B, Wang K, Liu F, Xiao H, Zhao J, Liu P, Li Y, Lin F and Wang Y. Mechano growth factor E peptide promotes osteoblasts proliferation and bone-defect healing in rabbits. Int Orthop. 2010. Nov 6. [Epub ahead of print]
27. Doty SB. Morphologic and histochemical studies of bone cells from SL-3 rats. Physiologist. 1985, 28(6 Suppl): S225-226.
28. Drissi H, Luc Q, Shakoori R, Chuva De Sousa Lopes S, Choi J-Y, Terry A, Hu M, Jones S, Neil JC, Lian JB, Stein JL, Van Wijnen AJ and Stein GS. Transcriptional autoregulation of the bone related CBFA1/RUNX2 gene. J Cell Physiol. 2000, 184(3): 341-350.
29. Drissi H, Pouliot A, Koolloos C, Stein JL, Lian JB, Stein GS and van Wijnen AJ. 1,25-(OH)2-Vitamin D3 Suppresses the Bone-Related Runx2/Cbfa1 Gene Promoter. Exp Cell Res. 2002, 274(2): 323-333.
30. Ducy P and Karsenty G. Two distinct osteoblast-specific cis-acting elements control expression of a mouse osteocalcin gene. Mol Cell Biol. 1995, 15(4): 1858-1869.
31. Ducy P, Zhang R, Geoffroy V, Ridall AL and Karsenty G. Osf2/Cbfa1: a transcriptional activator of osteoblast differentiation. Cell. 1997, 89(5): 747-754.
32. Foldes I, Rapcsak M, Szilagyi T and Oganov VS. Effects of space flight on bone formation and resorption. Acta Physiol Hung. 1990, 75(4): 271-285.
33. Forwood MR. Inducible cyclo-oxygenase (COX-2) mediates the induction of bone formation by mechanical loading in vivo. J Bone Miner Res. 1996, 11(11): 1688-1693.
34. Franceschi RT, Xiao G, Jiang D, Gopalakrishnan R, Yang S and Reith E. Multiple signaling pathways converge on the Cbfa1/Runx2 transcription factor to regulate osteoblast differentiation. Connect Tissue Res. 2003, 44(Suppl 1): 109-116.
35. Frigeri A, Iacobas DA, Iacobas S, Nicchia GP, Desaphy JF, Camerino DC, Svelto M and Spray DC. Effect of microgravity on gene expression in mouse brain. Exp Brain Res. 2008, 191(3): 289-300.
36. Frost H. A determination of bone architecture - the minimum effective strain. clin orthop. 1983, 200(2): 198-225.
37. Frost HM. A determinant of bone architecture. The minimum effective strain. Clin Orthop Relat Res. 1983, (175): 286-292.
38. Frost HM. The mechanostat: a proposed pathogenic mechanism of osteoporoses and the bone mass effects of mechanical and nonmechanical agents. Bone Miner. 1987, 2(2): 73-85.
39. Frost HM. The Utah paradigm of skeletal physiology: an overview of its insights for bone, cartilage and collagenous tissue organs. J Bone Miner Metab. 2000a, 18(6): 305-316.
40. Frost HM. Why the ISMNI and the Utah paradigm? Their role in skeletal and extraskeletal disorders. J Musculoskelet Neuronal Interact. 2000b, 1(1): 5-9.
41. Frost HM and Schonau E. The "muscle-bone unit" in children and adolescents: a 2000 overview. J Pediatr Endocrinol Metab. 2000, 13(6): 571-590.
42. Frost HM, Villanueva AR, Roth H and Stanisavljevic S. Tetracycline bone labeling. J New Drugs. 1961, 1: 206-216.
43. Fujita T, Azuma Y, Fukuyama R, Hattori Y, Yoshida C, Koida M, Ogita K and Komori T. Runx2 induces osteoblast and chondrocyte differentiation and enhances their migration by coupling with PI3K-Akt signaling. J Cell Biol. 2004, 166(1): 85-95.
44. Gaur T, Lengner CJ, Hovhannisyan H, Bhat RA, Bodine PV, Komm BS, Javed A, van Wijnen AJ, Stein JL, Stein GS and Lian JB. Canonical WNT signaling promotes osteogenesis by directly stimulating Runx2 gene expression. J Biol Chem. 2005, 280(39): 33132-33140.
45. Ge C, Xiao G, Jiang D and Franceschi RT. Critical role of the extracellular signal-regulated kinase-MAPK pathway in osteoblast differentiation and skeletal development. J Cell Biol. 2007, 176(5): 709-718.
46. Ge C, Xiao G, Jiang D, Yang Q, Hatch NE, Roca H and Franceschi RT. Identification and functional characterization of ERK/MAPK phosphorylation sites in the Runx2 transcription factor. J Biol Chem. 2009, 284(47): 32533-32543.
47. Gershovich JG and Buravkova LB. Morphofunctional status and osteogenic differentiation potential of human mesenchymal stromal precursor cells during in vitro modeling of microgravity effects. Bull Exp Biol Med. 2007, 144(4): 608-613.
48. Gershovich PM, Gershovich Iu G and Buravkova LB. [Cytoskeleton structures and adhesion properties of human stromal precursors under conditions of simulated microgravity]. Tsitologiia. 2009, 51(11): 896-904. abstract
49. Gronthos S, Chen S, Wang CY, Robey PG and Shi S. Telomerase accelerates osteogenesis of bone marrow stromal stem cells by upregulation of CBFA1, osterix, and osteocalcin. J Bone Miner Res. 2003, 18(4): 716-722.
50. Guignandon A, Lafage-Proust MH, Usson Y, Laroche N, Caillot-Augusseau A, Alexandre C and Vico L. Cell cycling determines integrin-mediated adhesion in osteoblastic ROS 17/2.8 cells exposed to space-related conditions. FASEB J. 2001, 15(11): 2036-2038.
51. Halloran BP, Bikle DD, Wronski TJ, Globus RK, Levens MJ and Morey-Holton E. The role of 1,25-dihydroxyvitamin D in the inhibition of bone formation induced by skeletal unloading. Endocrinology. 1986, 118(3): 948-954.
52. Heer M, Kamps N, Biener C, Korr C, Boerger A, Zittermann A, Stehle P and Drummer C. Calcium metabolism in microgravity. Eur J Med Res. 1999, 4(9): 357-360.
53. Hill TP, Spater D, Taketo MM, Birchmeier W and Hartmann C. Canonical Wnt/beta-catenin signaling prevents osteoblasts from differentiating into chondrocytes. Dev Cell. 2005, 8(5): 727-738.
54. Hinoi E, Fujimori S, Wang L, Hojo H, Uno K and Yoneda Y. Nrf2 negatively regulates osteoblast differentiation via interfering with Runx2-dependent transcriptional activation. J Biol Chem. 2006, 281(26): 18015-18024.
55. Hinton PS, LeCheminant JD, Smith BK, Rector RS and Donnelly JE. Weight loss-induced alterations in serum markers of bone turnover persist during weight maintenance in obese men and women. J Am Coll Nutr. 2009, 28(5): 565-573.
56. Hjelmeland AB, Schilling SH, Guo X, Quarles D and Wang XF. Loss of Smad3-mediated negative regulation of Runx2 activity leads to an alteration in cell fate determination. Mol Cell Biol. 2005, 25(21): 9460-9468.
57. Huang HY, Hu LL, Song TJ, Li X, He Q, Sun X, Li YM, Lu HJ, Yang PY and Tang QQ. Involvement of cytoskeleton-associated proteins in the commitment of C3H10T1/2 pluripotent stem cells to adipocyte lineage induced by BMP2/4. Mol Cell Proteomics. 2011, 10(1): M110 002691.
58. Huang Y, Dai Z, Ling S, Zhang H, Wan Y and Li Y. Gravity, a regulation factor in the differentiation of rat bone marrow mesenchymal stem cells. J Biomed Sci. 2009, 16: 87.
59. Hughes-Fulford M. Altered cell function in microgravity. Exp Gerontol. 1991, 26(2-3): 247-256.
60. Hughes-Fulford M. Function of the cytoskeleton in gravisensing during spaceflight. Adv Space Res. 2003, 32(8): 1585-1593.
61. Hughes-Fulford M and Lewis ML. Effects of microgravity on osteoblast growth activation. Exp Cell Res. 1996, 224(1): 103-109.
62. Hughes-Fulford M, Rodenacker K and Jutting U. Reduction of anabolic signals and alteration of osteoblast nuclear morphology in microgravity. J Cell Biochem. 2006, 99(2): 435-449.
63. Javed A, Guo B, Hiebert S, Choi JY, Green J, Zhao SC, Osborne MA, Stifani S, Stein JL, Lian JB, van Wijnen AJ and Stein GS. Groucho/TLE/R-esp proteins associate with the nuclear matrix and repress RUNX (CBF(alpha)/AML/PEBP2(alpha)) dependent activation of tissue-specific gene transcription. J Cell Sci. 2000, 113(Pt12): 2221-2231.
64. Javed A, Gutierrez S, Montecino M, van Wijnen AJ, Stein JL, Stein GS and Lian JB. Multiple Cbfa/AML sites in the rat osteocalcin promoter are required for basal and vitamin D-responsive transcription and contribute to chromatin organization. Mol Cell Biol. 1999, 19(11): 7491-7500.
65. Jee WS, Wronski TJ, Morey ER and Kimmel DB. Effects of spaceflight on trabecular bone in rats. Am J Physiol. 1983, 244(3): R310-314.
66. Jeon EJ, Lee KY, Choi NS, Lee MH, Kim HN, Jin YH, Ryoo HM, Choi JY, Yoshida M, Nishino N, Oh BC, Lee KS, Lee YH and Bae SC. Bone morphogenetic protein-2 stimulates Runx2 acetylation. J Biol Chem. 2006, 281(24): 16502-16511.
67. Jun JH, Yoon WJ, Seo SB, Woo KM, Kim GS, Ryoo HM and Baek JH. BMP2-activated Erk/MAP kinase stabilizes Runx2 by increasing p300 levels and histone acetyltransferase activity. J Biol Chem. 2010, 285(47): 36410-36419.
68. Kassem M. Mesenchymal stem cells: biological characteristics and potential clinical applications. Cloning Stem Cells. 2004, 6(4): 369-374.
69. Kawarizadeh A, Bourauel C, Gotz W and Jager A. Early responses of periodontal ligament cells to mechanical stimulus in vivo. J Dent Res. 2005, 84(10): 902-906.
70. Kim IS, Song YM, Cho TH, Kim JY, Weber FE and Hwang SJ. Synergistic action of static stretching and BMP-2 stimulation in the osteoblast differentiation of C2C12 myoblasts. J Biomech. 2009, 42(16): 2721-2727.
71. Kobayashi H, Gao Y, Ueta C, Yamaguchi A and Komori T. Multilineage differentiation of Cbfa1-deficient calvarial cells in vitro. Biochem Biophys Res Commun. 2000, 273(2):630-636.
72. Komori T. Runx2, a multifunctional transcription factor in skeletal development. J Cell Biochem. 2002, 87(1): 1-8.
73. Komori T, Yagi H, Nomura S, Yamaguchi A, Sasaki K, Deguchi K, Shimizu Y, Bronson RT, Gao YH, Inada M, Sato M, Okamoto R, Kitamura Y, Yoshiki S and Kishimoto T. Targeted disruption of Cbfa1 results in a complete lack of bone formation owing to maturational arrest of osteoblasts. Cell. 1997, 89(5): 755-764.
74. Kostenuik PJ, Halloran BP, Morey-Holton ER and Bikle DD. Skeletal unloading inhibits the in vitro proliferation and differentiation of rat osteoprogenitor cells. Am J Physiol. 1997, 273(6 Pt 1): E1133-1139.
75. Kumei Y, Nakamura H, Morita S, Akiyama H, Hirano M, Ohya KI, Shinomiya KI and Shimokawa H. Space Flight and Insulin-like Growth Factor-I Signaling in Rat Osteoblasts. Annals of the New York Academy of Sciences. 2002, 973(1): 75-78.
76. Kumei Y, Shimokawa H, Katano H, Akiyama H, Hirano M, Mukai C, Nagaoka S, Whitson PA and Sams CF. Spaceflight modulates insulin-like growth factor binding proteins and glucocorticoid receptor in osteoblasts. J Appl Physiol. 1998, 85(1): 139-147.
77. Kumei Y, Shimokawa H, Katano H, Hara E, Akiyama H, Hirano M, Mukai C, Nagaoka S, Whitson PA and Sams CF. Microgravity induces prostaglandin E2 and interleukin-6 production in normal rat osteoblasts: role in bone demineralization. J Biotechnol. 1996, 47(2-3): 313-324.
78. Kunisada T, Kawai A, Inoue H and Namba M. Effects of simulated microgravity on human osteoblast-like cells in culture. Acta Med Okayama. 1997, 51(3): 135-140.
79. Leach CS, Johnson PC and Cintron NM. The endocrine system in space flight. Acta Astronaut. 1988, 17(2): 161-166.
80. LeBlanc A, Schneider V, Shackelford L, West S, Oganov V, Bakulin A and Voronin L (2000). Bone mineral and lean tissue loss after long duration space flight. J Musculoskelet Neuronal Interact. 1: 157-160.
81. LeBlanc A, Shackelford L and Schneider V. Future human bone research in space. Bone. 1998, 22(5 Suppl): 113S-116S.
82. Lee JH, Kim BG, Ahn JM, Park HJ, Park SK, Yoo JS, Yates JR, 3rd and Cho JY. Role of PI3K on the regulation of BMP2-induced beta-Catenin activation in human bone marrow stem cells. Bone. 2010, 46(6): 1522-1532.
83. Lee MH, Javed A, Kim HJ, Shin HI, Gutierrez S, Choi JY, Rosen V, Stein JL, van Wijnen AJ, Stein GS, Lian JB and Ryoo HM. Transient upregulation of CBFA1 in response to bone morphogenetic protein-2 and transforming growth factor beta1 in C2C12 myogenic cells coincides with suppression of the myogenic phenotype but is not sufficient for osteoblast differentiation. J Cell Biochem. 1999, 73(1): 114-125.
84. Li TF, Dong Y, Ionescu AM, Rosier RN, Zuscik MJ, Schwarz EM, O'Keefe RJ and Drissi H. Parathyroid hormone-related peptide (PTHrP) inhibits Runx2 expression through the PKA signaling pathway. Exp Cell Res. 2004, 299(1): 128-136.
85. Linkhart TA, Mohan S and Baylink DJ. Growth factors for bone growth and repair: IGF, TGFβand BMP. Bone. 1996, 19(1): S1-S12.
86. Machwate M, Zerath E, Holy X, Hott M, Modrowski D, Malouvier A and Marie PJ. Skeletal unloading in rat decreases proliferation of rat bone and marrow-derived osteoblastic cells. Am J Physiol. 1993, 264(5 Pt 1): E790-799.
87. Maehata Y, Takamizawa S, Ozawa S, Kato Y, Sato S, Kubota E and Hata R. Both direct and collagen-mediated signals are required for active vitamin D3-elicited differentiation of human osteoblastic cells: roles of osterix, an osteoblast-related transcription factor. Matrix Biol. 2006, 25(1): 47-58.
88. Mehrotra M, Saegusa M, Voznesensky O and Pilbeam C. Role of Cbfa1/Runx2 in the fluid shear stress induction of COX-2 in osteoblasts. Biochem Biophys Res Commun. 2006, 341(4): 1225-1230.
89. Meng R, Xu HY, Di SM, Shi DY, Qian AR, Wang JF and Shang P. Human mesenchymal stem cells are sensitive to abnormal gravity and exhibit classic apoptotic features. Acta Biochim Biophys Sin. 2011, 43(2): 133-142.
90. Merzlikina NV, Buravkova LB and Romanov YA. The primary effects of clinorotation on cultured human mesenchymal stem cells. J Gravit Physiol. 2004, 11(2): P193-194.
91. Meyers VE, Zayzafoon M, Douglas JT and McDonald JM. RhoA and cytoskeletal disruption mediate reduced osteoblastogenesis and enhanced adipogenesis of human mesenchymal stem cells in modeled microgravity. J Bone Miner Res. 2005, 20(10): 1858-1866.
92. Meyers VE, Zayzafoon M, Gonda SR, Gathings WE and McDonald JM. Modeled microgravity disrupts collagen I/integrin signaling during osteoblastic differentiation of human mesenchymal stem cells. Journal of Cellular Biochemistry. 2004a, 93(4): 697-707.
93. Meyers VE, Zayzafoon M, Gonda SR, Gathings WE and McDonald JM. Modeled microgravity disrupts collagen I/integrin signaling during osteoblastic differentiation of human mesenchymal stem cells. J Cell Biochem. 2004b, 93(4): 697-707.
94. Mikuni-Takagaki Y, Suzuki Y, Kawase T and Saito S. Distinct responses of different populations of bone cells to mechanical stress. Endocrinology. 1996, 137(5): 2028-2035.
95. Monticone M, Liu Y, Pujic N and Cancedda R. Activation of nervous system development genes in bone marrow derived mesenchymal stem cells following spaceflight exposure. J Cell Biochem. 2010, 111(2): 442-452.
96. Morey-Holton ER and Globus RK. Hindlimb unloading of growing rats: a model for predicting skeletal changes during space flight. Bone. 1998, 22(5 Suppl): 83S-88S.
97. Morey-Holton ER and Globus RK. Hindlimb unloading rodent model: technical aspects. J Appl Physiol. 2002, 92(4): 1367-1377.
98. Morey-Holton ER, Schnoes HK, DeLuca HF, Phelps ME, Klein RF, Nissenson RH and Arnaud CD. Vitamin D metabolites and bioactive parathyroid hormone levels during Spacelab 2. Aviat Space Environ Med. 1988, 59(11Pt1): 1038-1041.
99. Morey-Holton ER, Whalen RT, Arnaud SB and Van der Meulen MC. The Skeleton and its Adaptation to Gravity, John Wiley & Sons, Inc.2011. online
100. Morey ER and Baylink DJ. Inhibition of bone formation during space flight. Science. 1978, 201(4361): 1138-1141.
101. Nakasaki M, Yoshioka K, Miyamoto Y, Sasaki T, Yoshikawa H and Itoh K. IGF-I secreted by osteoblasts acts as a potent chemotactic factor for osteoblasts. Bone. 2008, 43(5): 869-879.
102. Narayanan R, Smith CL and Weigel NL. Vector-averaged gravity-induced changes in cell signaling and vitamin d receptor activity in MG-63 cells are reversed by a 1,25-(OH)2D3 analog, EB1089. Bone. 2002, 31(3): 381-388.
103. Oganov VS, Rakhmanov AS, Novikov VE, Zatsepin ST, Rodionova SS and Cann C. The state of human bone tissue during space flight. Acta Astronaut. 1991, 23: 129-133.
104. Ogata N, Chikazu D, Kubota N, Terauchi Y, Tobe K, Azuma Y, Ohta T, Kadowaki T, Nakamura K and Kawaguchi H. Insulin receptor substrate-1 in osteoblast is indispensable for maintaining bone turnover. J Clin Invest. 2000, 105(7): 935-943.
105. Okazaki K, Jingushi S, Ikenoue T, Urabe K, Sakai H and Iwamoto Y. Expression of parathyroid hormone-related peptide and insulin-like growth factor I during rat fracture healing. J Orthop Res. 2003, 21(3): 511-520.
106. Otto F, Thornell AP, Crompton T, Denzel A, Gilmour KC, Rosewell IR, Stamp GW, Beddington RS, Mundlos S, Olsen BR, Selby PB and Owen MJ. Cbfa1, a candidate gene for cleidocranial dysplasia syndrome, is essential for osteoblast differentiation and bone development. Cell. 1997, 89(5): 765-771.
107. Paredes R, Arriagada G, Cruzat F, Villagra A, Olate J, Zaidi K, van Wijnen A, Lian JB, Stein GS, Stein JL and Montecino M. Bone-specific transcription factor Runx2 interacts with the 1alpha,25-dihydroxyvitamin D3 receptor to up-regulate rat osteocalcin gene expression in osteoblastic cells. Mol Cell Biol. 2004, 24(20): 8847-8861.
108. Pei Y, Meng XW, Zhou XY, Xing XP and Xia WB. Expression of core binding factor alpha1 up-regulated by IGF-I, GM-CSF, and EGF through MAPK pathway in MC3T3-E1 and C2C12 cells. Acta Pharmacol Sin. 2003, 24(10): 975-984.
109. Pelletier N, Champagne N, Stifani S and Yang XJ. MOZ and MORF histone acetyltransferases interact with the Runt-domain transcription factor Runx2. Oncogene. 2002, 21(17): 2729-2740.
110. Pittenger MF, Mackay AM, Beck SC, Jaiswal RK, Douglas R, Mosca JD, Moorman MA, Simonetti DW, Craig S and Marshak DR. Multilineage potential of adult human mesenchymal stem cells. Science. 1999, 284(5411): 143-147.
111. Plett PA, Frankovitz SM, Abonour R and Orschell-Traycoff CM. Proliferation of human hematopoietic bone marrow cells in simulated microgravity. In Vitro Cell Dev Biol Anim. 2001, 37(2): 73-78.
112. Qi MC, Zou SJ, Han LC, Zhou HX and Hu J. Expression of bone-related genes in bone marrow MSCs after cyclic mechanical strain: implications for distraction osteogenesis. Int J Oral Sci. 2009, 1(3): 143-150.
113. Qiao M, Shapiro P, Kumar R and Passaniti A. Insulin-like growth factor-1 regulates endogenous RUNX2 activity in endothelial cells through a phosphatidylinositol 3-kinase/ERK-dependent and Akt-independent signaling pathway. J Biol Chem. 2004, 279(41): 42709-42718.
114. Raab-Cullen DM, Thiede MA, Petersen DN, Kimmel DB and Recker RR. Mechanical loading stimulates rapid changes in periosteal gene expression. Calcif Tissue Int. 1994, 55(6): 473-478.
115. Rambaut PC and Johnston RS. Prolonged weightlessness and calcium loss in man. Acta Astronaut. 1979, 6(9): 1113-1122.
116. Rector RS, Loethen J, Ruebel M, Thomas TR and Hinton PS. Serum markers of bone turnover are increased by modest weight loss with or without weight-bearing exercise in overweight premenopausal women. Appl Physiol Nutr Metab. 2009, 34(5): 933-941.
117. Reijnders CMA, Bravenboer N, Tromp AM, Blankenstein MA and Lips P. Effect of mechanical loading on insulin-like growth factor-I gene expression in rat tibia. J Endocrinol. 2007, 192(1): 131-140.
118. Rijken PJ, de Groot RP, Kruijer W, de Laat SW, Verkleij AJ and Boonstra J. Identification of specific gravity sensitive signal transduction pathways in human A431 carcinoma cells. Adv Space Res. 1992, 12(1): 145-152.
119. Rijken PJ, de Groot RP, van Belzen N, de Laat SW, Boonstra J and Verkleij AJ. Inhibition of EGF-induced signal transduction by microgravity is independent of EGF receptor redistribution in the plasma membrane of human A431 cells. Exp Cell Res. 1993, 204(2): 373-377.
120. Roberts W, Mozsary P and Morey E. Suppression of osteoblast differentiation during weightlessness. J Physiologist. 1981, 24: S75-76.
121. Robling AG and Turner CH. Mechanical signaling for bone modeling and remodeling. Crit Rev Eukaryot Gene Expr. 2009, 19(4): 319-338.
122. Rodionova NV, Shevel IM, Oganov VS, Novikov VE and Kabitskaya OE. Bone ultrastructural changes in Bion 11 rhesus monkeys. J Gravit Physiol. 2000, 7(1): S157-161.
123. Russell JE and Simmons DJ. Bone maturation in rats flown on the Spacelab-3 mission. Physiologist. 1985, 28(6 Suppl): S235-236.
124. Sakata T, Halloran BP, Elalieh HZ, Munson SJ, Rudner L, Venton L, Ginzinger D, Rosen CJ and Bikle DD. Skeletal unloading induces resistance to insulin-like growth factor I on bone formation. Bone. 2003, 32(6): 669-680.
125. Sakata T, Wang Y, Halloran BP, Elalieh HZ, Cao J and Bikle DD. Skeletal unloading induces resistance to insulin-like growth factor-I (IGF-I) by inhibiting activation of the IGF-I signaling pathways. J Bone Miner Res. 2004, 19(3): 436-446.
126. Salingcarnboriboon R, Tsuji K, Komori T, Nakashima K, Ezura Y and Noda M. Runx2 Is a Target of Mechanical Unloading to Alter Osteoblastic Activity and Bone Formation in Vivo. Endocrinology. 2006, 147(5): 2296-2305.
127. Sarkar D, Nagaya T, Koga K, Nomura Y, Gruener R and Seo H. Culture in vector-averaged gravity under clinostat rotation results in apoptosis of osteoblastic ROS 17/2.8 cells. J Bone Miner Res. 2000, 15(3): 489-498.
128. Schneider V, Oganov V, LeBlanc A, Rakmonov A, Taggart L, Bakulin A, Huntoon C, Grigoriev A and Varonin L. Bone and body mass changes during space flight. Acta Astronaut. 1995, 36(8-12): 463-466.
129. Schoenau E and Frost H. The muscle strength-bone strength relationship in human. A review. Third international congress on osteoporosis,Xi'an China. 1999: 84-89.
130. Seino Y. Cytokines and growth factors which regulate bone cell function. Acta Astronautica. 1994, 33: 131-136.
131. Sessions ND, Halloran BP, Bikle DD, Wronski TJ, Cone CM and Morey-Holton E. Bone response to normal weight bearing after a period of skeletal unloading. Am J Physiol. 1989, 257(4Pt1): E606-610.
132. Sheyn D, Pelled G, Netanely D, Domany E and Gazit D. The effect of simulated microgravity on human mesenchymal stem cells cultured in an osteogenic differentiation system: a bioinformatics study. Tissue Eng Part A. 2010, 16(11): 3403-3412.
133. Shi D, Meng R, Deng W, Ding W, Zheng Q, Yuan W, Liu L, Zong C, Shang P and Wang J. Effects of microgravity modeled by large gradient high magnetic field on the osteogenic initiation of human mesenchymal stem cells. Stem Cell Rev. 2010, 6(4): 567-578.
134. Shindo K, Kawashima N, Sakamoto K, Yamaguchi A, Umezawa A, Takagi M, Katsube K and Suda H. Osteogenic differentiation of the mesenchymal progenitor cells, Kusa is suppressed by Notch signaling. Exp Cell Res. 2003, 290(2): 370-380.
135. Sierra J, Villagra A, Paredes R, Cruzat F, Gutierrez S, Javed A, Arriagada G, Olate J, Imschenetzky M, Van Wijnen AJ, Lian JB, Stein GS, Stein JL and Montecino M. Regulation of the bone-specific osteocalcin gene by p300 requires Runx2/Cbfa1 and the vitamin D3 receptor but not p300 intrinsic histone acetyltransferase activity. Mol Cell Biol. 2003, 23(9): 3339-3351.
136. Simmons DJ, Russell JE, Winter F, Baron R, Vignery A, Tran VT, Rosenberg GD and Walker W. Bone growth in the rat mandible during space flight. Physiologist. 1980, 23(Suppl 6): S87-90.
137. Sooy K, Sabbagh Y and Demay MB. Osteoblasts lacking the vitamin D receptor display enhanced osteogenic potential in vitro. J Cell Biochem. 2005, 94(1): 81-87.
138. Sumanasinghe RD, Bernacki SH and Loboa EG. Osteogenic differentiation of human mesenchymal stem cells in collagen matrices: effect of uniaxial cyclic tensile strain on bone morphogenetic protein (BMP-2) mRNA expression. Tissue Eng. 2006, 12(12): 3459-3465.
139. Sun L, Gan B, Fan Y, Xie T, Hu Q and Zhuang F. Simulated microgravity alters multipotential differentiation of rat mesenchymal stem cells in association with reduced telomerase activity. Acta Astronautica. 2008, 63(7-10): 968-973.
140. Susperregui AR, Vinals F, Ho PW, Gillespie MT, Martin TJ and Ventura F. BMP-2 regulation of PTHrP and osteoclastogenic factors during osteoblast differentiation of C2C12 cells. J Cell Physiol. 2008, 216(1): 144-152.
141. Tang LL, Qiu M, Li DJ, Jiang FY and Wang YL (2010). The Effects of MGF on the Physiological Behaviors of Osteoblasts. World Congress on Medical Physics and Biomedical Engineering, September 7-12, 2009, Munich, Germany. O D?ssel and WC Schlegel, Springer Berlin Heidelberg. 25/10: 113-115. abstract
142. Tang LL, Xian CY and Wang YL. The MGF expression of osteoblasts in response to mechanical overload. Arch Oral Biol. 2006, 51(12): 1080-1085.
143. Tilton FE, Degioanni JJ and Schneider VS. Long-term follow-up of Skylab bone demineralization. Aviat Space Environ Med. 1980, 51(11): 1209-1213.
144. Tintut Y, Parhami F, Le V, Karsenty G and Demer LL. Inhibition of osteoblast-specific transcription factor Cbfa1 by the cAMP pathway in osteoblastic cells. Ubiquitin/proteasome-dependent regulation. J Biol Chem. 1999, 274(41): 28875-28879.
145. Trudel G, Payne M, Madler B, Ramachandran N, Lecompte M, Wade C, Biolo G, Blanc S, Hughson R, Bear L and Uhthoff HK. Bone marrow fat accumulation after 60 days of bed rest persisted 1 year after activities were resumed along with hemopoietic stimulation: the Women International Space Simulation for Exploration study. J Appl Physiol. 2009, 107(2): 540-548.
146. Turner RT, Evans GL and Wakley GK. Spaceflight results in depressed cancellous bone formation in rat humeri. Aviat Space Environ Med. 1995, 66(8): 770-774.
147. Vico L, Chappard D, Palle S, Bakulin AV, Novikov VE and Alexandre C. Trabecular bone remodeling after seven days of weightlessness exposure (BIOCOSMOS 1667). Am J Physiol. 1988, 255(2Pt2): R243-247.
148. Vico L, Collet P, Guignandon A, Lafage-Proust MH, Thomas T, Rehaillia M and Alexandre C. Effects of long-term microgravity exposure on cancellous and cortical weight-bearing bones of cosmonauts. Lancet. 2000, 355(9215): 1607-1611.
149. Viereck V, Siggelkow H, Tauber S, Raddatz D, Schutze N and Hüfner M. Differential regulation of Cbfa1/Runx2 and osteocalcin gene expression by vitamin-D3, dexamethasone, and local growth factors in primary human osteoblasts. J Cell Biochem. 2002, 86(2): 348-356.
150. Wang W, Wang Y-G, Reginato AM, Glotzer DJ, Fukai N, Plotkina S, Karsenty G and Olsen BR. Groucho homologue Grg5 interacts with the transcription factor Runx2-Cbfa1 and modulates its activity during postnatal growth in mice. Dev Bio. 2004, 270(2): 364-381.
151. Wang YL and Zhang BB. The Effects of MGF and E Peptide on The Differentiation of Osteoblasts. Progress in Biochemistry and Biophysics. 2010, 37(3): 304.
152. Wimalawansa SM and Wimalawansa SJ. A novel pharmacological approach of musculoskeletal losses associated with simulated microgravity. J Musculoskelet Neuronal Interact. 2000, 1(1): 35-41.
153. Wu X, Shi W and Cao X. Multiplicity of BMP signaling in skeletal development. Ann N Y Acad Sci. 2007, 1116: 29-49.
154. Xian C, Wang Y, Zhang B, Tang L, Pan J, Luo Y, Jiang P and Li D. Alternative splicing and expression of the insulin-like growth factor (IGF-1) gene in osteoblasts under mechanical stretch. Chinese Sci Bull. 2006, 51(22): 2731-2736.
155. Xiao G, Jiang D, Gopalakrishnan R and Franceschi RT. Fibroblast growth factor 2 induction of the osteocalcin gene requires MAPK activity and phosphorylation of the osteoblast transcription factor, Cbfa1/Runx2. J Biol Chem. 2002, 277(39): 36181-36187.
156. Xiao G, Jiang D, Thomas P, Benson MD, Guan K, Karsenty G and Franceschi RT. MAPK pathways activate and phosphorylate the osteoblast-specific transcription factor, Cbfa1. J Biol Chem. 2000, 275(6): 4453-4459.
157. Yang S, Alnaqeeb M, Simpson H and Goldspink G. Cloning and characterization of an IGF-1 isoform expressed in skeletal muscle subjected to stretch. J Muscle Res Cell Motil. 1996, 17(4): 487-495.
158. Yang Y, Li X, Cui L, Fu M, Rabie AB and Zhang D. Functional analysis of core binding factor a1 and its relationship with related genes expressed by human periodontal ligament cells exposed to mechanical stress. Eur J Orthod. 2010, 32(6): 698-705.
159. Yeni YN, Dong XN, Zhang B, Gibson GJ and Fyhrie DP. Cancellous bone properties and matrix content of TGF-beta2 and IGF-I in human tibia: a pilot study. Clin Orthop Relat Res. 2009, 467(12): 3079-3086.
160. Yuge L, Kajiume T, Tahara H, Kawahara Y, Umeda C, Yoshimoto R, Wu SL, Yamaoka K, Asashima M, Kataoka K and Ide T. Microgravity potentiates stem cell proliferation while sustaining the capability of differentiation. Stem Cells Dev. 2006, 15(6): 921-929.
161. Zaragoza C, Lopez-Rivera E, Garcia-Rama C, Saura M, Martinez-Ruiz A, Lizarbe TR, Martin-de-Lara F and Lamas S. Cbfa-1 mediates nitric oxide regulation of MMP-13 in osteoblasts. J Cell Sci. 2006, 119(Pt 9): 1896-1902.
162. Zayzafoon M, Gathings WE and McDonald JM. Modeled microgravity inhibits osteogenic differentiation of human mesenchymal stem cells and increases adipogenesis. Endocrinology. 2004, 145(5): 2421-2432.
163. Zerath E, Holy X, Roberts SG, Andre C, Renault S, Hott M and Marie PJ. Spaceflight inhibits bone formation independent of corticosteroid status in growing rats. J Bone Miner Res. 2000, 15(7): 1310-1320.
164. Zhang BB, Xian CY, Luo YF and Wang YL. Expression and subcellular localization of mechano-growth factor in osteoblasts under mechanical stretch. Sci China Ser C. 2009, 52(10): 928-934.
165. Zhang S, Wang B, Cao XS, Yang Z and Sun XQ. The influence of fluid shear stress on the expression of Cbfa1 in MG-63 cells cultured under different gravitational conditions. Adv Space Res. 2008, 42(12): 1980-1985.
166. Zheng Q, Huang G, Yang J, Xu Y, Guo C, Xi Y, Pan Z and Wang J. Could the effect of modeled microgravity on osteogenic differentiation of human mesenchymal stem cells be reversed by regulation of signaling pathways? Biol Chem. 2007, 388(7): 755-763.
167. Ziambaras K, Civitelli R and Papavasiliou SS. Weightlessness and skeleton homeostasis. Hormones (Athens). 2005, 4(1): 18-27.
168. Ziros PG, Gil AP, Georgakopoulos T, Habeos I, Kletsas D, Basdra EK and Papavassiliou AG. The bone-specific transcriptional regulator Cbfa1 is a target of mechanical signals in osteoblastic cells. J Biol Chem. 2002, 277(26): 23934-23941.
169. Zittermann A, Heer M, Caillot-Augusso A, Rettberg P, Scheld K, Drummer C, Alexandre C, Horneck G, Vorobiev D and Stehle P. Microgravity inhibits intestinal calcium absorption as shown by a stable strontium test. Eur J Clin Invest. 2000, 30(12): 1036-1043.
170.崔伟.微重力条件下骨矿盐丢失机理.生理科学进展. 1998, 29(1): 84-86.
171.崔伟,江涛,胡平,郑强,杨光华.模拟失重大鼠骨矿盐变化特点及机理.空间科学学报. 1996a, 16: S42-S46.
172.崔伟,史之祯.模拟失重大鼠颅盖骨、椎骨中氨基多糖与矿盐变化的研究.航天医学与医学工程. 1995, 8(1): 46-48.
173.崔伟,史之祯,付宏伟,郑强,邱连俊.两种骨丢失动物模型骨质、甲状旁腺激素和降钙素的变化比较.中国应用生理学杂志. 1997, 13(1): 5-8.
174.崔伟,史之祯,郑强.不同悬吊时间对大鼠椎骨骨质和生物力学特性的影响.航天医学与医学工程. 1996b, 9(3): 190-194.
175.邓红文,刘耀中(2006).骨生物学前沿.北京,高等教育出版社: 18-31.
176.付强,刘艳辉,徐亚娟,郭玲,吴昌敬.细胞体外流体剪切力加载装置平行平板流室的合理设计与应用.中山大学学报(医学科学版). 2009, 30(3S): 68-71.
177.傅崇建,杨连甲,曹新生,陈希哲,张立藩.模拟失重下大鼠骨和骨髓中人重组骨形成蛋白-2的变化.航天医学与医学工程. 2001, 14(4): 295-297.
178.高书明.防骨质疏松运动比补钙更重要.中国保健营养. 2004, (9): 1.
179.胡蕴玉.现代骨科基础与临床.北京:人民卫生出版社. 2006: 44-46.
180.克莱芒著,陈善广译.航天医学基础.北京,北京宇航出版社.2008.
181.李婵娟,顾海燕,赵德育,刘晓梅,张翔. RNA干扰沉默VDR基因对小鼠成骨细胞Dmp1,Cbfa1及BMP-2 mRNA表达的影响.南京医科大学学报(自然科学版). 2009, 29(05): 669-673.
182.廖保强,邓墨渊,傅亚,王远亮,饶泉珍.力生长因子对免桡骨骨折愈合的作用.中国组织工程研究与临床康复. 2010, 14(2): 4.
183.刘肖珩,尹红梅,陈槐卿,Wang X. Flow chamber流动试验模型.生物数学学报. 2002, 17(4): 416-420.
184.裴育,夏维波,邢小平,周学瀛,孟迅吾. VEGF通过MAPK途径上调MC3T3-E1及C2C12细胞中Cbfa1基因的表达.中华骨质疏松和骨矿盐疾病杂志. 2009, 2(2): 120-126.
185.沈羡云,任维(2007).失重生理学基础与进展.北京,国防工业出版社.
186.沈羡云,薛月英.航天重力生理学与医学.北京,国防工业出版社.2001.
187.孙红梅,李春义,杨福合,赵海平,鲁小平,褚文辉. Cbfa1基因结构与功能分析.特产研究. 2009, 31(1): 5.
188.汪涛,杨光华.模拟失重对大鼠肿瘤坏死因子-α含量和骨髓细胞对粒巨细胞集落剌激因子反应性的影响航天医学与医学工程. 1997, 10(3): 168-171.
189.王冰,曹新生,吴燕红,杨志,张舒.模拟失重对骨形态发生蛋白2(BMP-2)诱导的ROS17/2.8细胞中ERK活性的影响.航天医学与医学工程. 2006, 19(6): 4.
190.王冰,张舒,吴兴裕.模拟失重条件下骨形态发生蛋白-2对大鼠骨肉瘤成骨样细胞基因表达的影响.航天医学与医学工程. 2004, 17(3): 4.
191.王常德,夏亚一.流体剪切力对成骨细胞影响的研究进展.临床骨科杂志. 2009, 12(3): 4.
192.吴燕红,王冰,曹新生,杨志,张舒.模拟失重对流体剪切应力诱导MG-63细胞ERK2激活的影响.航天医学与医学工程. 2007, 20(5): 4.
193.杨志,王冰,孙喜庆,张舒.流体剪切应力对模拟失重条件下MG-63成骨样细胞Cbfα1表达的影响.航天医学与医学工程. 2007, 20(1): 5.
194.张兵兵,王远亮,杨力,潘长江,傅亚,邓墨渊,李玉筱.力生长因子及其E肽对成骨细胞分化的影响.生物化学与生物物理进展. 2010, 37(3): 304-312.
195.张兵兵,鲜成玉,韩莉,李大军,唐丽灵,王远亮.拉伸刺激下力生长因子在成骨细胞中的表达.中华创伤杂志. 2009, 25(2): 4.
196.张舒,吴兴裕,李莹辉,谢力勤.模拟失重对流体剪切应力诱导成骨细胞环氧合酶-2表达的影响.航天医学与医学工程. 2002, 15(1): 5.
197.张舒,吴兴裕,李莹辉,张晓铀.模拟失重对流体剪切应力致大鼠颅骨成骨细胞PGE2分泌的影响.航天医学与医学工程. 2001, 14(4): 5.
198.张晓铀,汪恭质,丁柏,李莹辉,谭映军.模拟失重对成骨样细胞细胞周期变化的影响.中华航空航天医学杂志. 2000, 11(1): 43-45.