Objective To study the effect of microgravity on the bone itself and metabolism.Methods 8-week-old widetype C57 mice were tail-suspended for 0, 2, 4, weeks. Related serum biochemical indices (Ca2+, ALP, BGP) were measured. Microstructure of bone was observed by micro-CT scanning. Three point bending test on the femurs by material testing machine helped to compare the changes of mechanical parameters. All the data were analysed.by SPSS18.0.Results Compared with control group, tail-suspended groups had a higher concentration in calcium in serum,the values of which were (2.134±0.08114) mmol/L, (2.261±0.07913) mmol/L, and (2.388±0.06112) mmol/L; lower levels of serum ALP and BGP, the difference was significant with a longer tail-suspension. The values of ALP was (4.598±0.4783) U/100 ml, (3.447±0.3930) U/100 ml, and (3.142±0.3280) U/100 ml; and the values of BGP were (8.529±0.5233) ng/ml, (8.108±0.3920) ng/ml, and (7.832±0.2821) ng/ml, which had statistically significant difference compared with control group (P<0.05).The scanning of femur showed obviously osteoporosis in tail-suspended mice. Compared with control group, number of bone trabecular reduced, the gap between them widened, thickness decreased simultaneously in the tail-suspended mice. Among which, BV/TV decreased most, the values of tailed-suspension for 2 and 4 weeks were 47.3% and 14.3% in the control group; There was a positive relationship between the osteoporosis and the time of tail-suspension. Mechanical parameters showed that the force decreased as well. Simulated microgravity promoted the loss of calcium in bone, mechanical properties of femurs of suspended-mice decreased, their capability of resistance to force decreasedas well. The forces to bone fracture in tailed-suspension for 0, 2 and 4 weeks were (6.220±0.482)mJ, (4.395±0.301)mJ, and (2.855±0.425)mJ, which had statistically significant difference compared with control group (P<0.05).Conclusions Simulated microgravity promotes the loss of calcium in bone, which can lead to osteoporosis, and the degree of that has a positive relationship to the time.
Key words
microgravity /
tail suspension /
osteoporosis /
mouse
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References
[1] Saxena R, Pan G, McDonald J M. Osteoblast and osteoclast differentiation in modeled microgravity [J]. Ann N Y Acad Sci, 2007,1116:494-498.
[2] 董 松,崔立芹,雷 蕾,等.2型糖尿病并发骨质疏松的相关危险因素[J]. 武警医学,2015,26(8):824-827.
[3] 宫丽娜,牛志燕,苏 巍.糖皮质激素性骨质疏松伴多发脆性骨折[J]. 武警医学,2015,26(7):753-754.
[4] Ohshima H, Mukai C. Bone metabolism in human space flight and bed rest study[J]. Clin Calcium, 2008,18(9): 1245-1253.
[5] 史 晓,王 翔,杜修东,等. 大鼠尾悬吊骨质疏松模型初探[J].中国现代医学杂志2009,19(2): 341-343.
[6] 章晓东,余 震,刘纳新.大鼠体力及精神状态评价的行为学新技术[J].温州医学院学报,2009,13(2):137-140.
[7] 宋 敏,李 晶.大鼠骨质疏松模型的复制方法及意义[J].当代医学,2012,8(6):16-18.
[8] Guo R, Hh M, Sun Z Y, et al. Effects of simulated weightlessness on rats mandible, lumbar vertebra and femur [J]. SpaceM Med Eng, 2005, 18(3):165-169.
[9] Dave V, Lafage P H, Laroche N, et al. Two-week longitud in al survey of bone arch-itecture alteration in the hind limb-unloaded rat model of bone loss:sex differences[J].Am J Physiol Endocrinol Metab,2014,9(3):440-447.
[10] Tsuji H, Cawthorn C, Ecarot B. Abnormal modulation of serum osteocalcin by dietary phosphate and 1,25-dihydroxyvitamin D3 in the hypophosphatemic mouse [J].Bone Miner Res,2013, 11(9): 1234-1240.
[11] 付重建,郁冰冰,杨连甲,等.尾悬吊大鼠骨和骨髓中骨钙素的变化[J].航天医学与医学工程,2005,16(4):260-263.
[12] Wu D D, Boyd R D, Fix T J, et al. Regional patterns of bone loss and altered bone remodeling in response to calcium deprivation in laboratory rabbits [J]. Calcif Tissue Int, 1990, 47(1): 18-23.
[13] 李 昊, 李瑞欣, 张西正, 等. 周期性动态力学载荷对抗骨质疏松的研究[C].北京:军事医学科学院出版社,2013:31-42.
[14] Zhu W, Yang M L, Yang GY, et al. Changes in serum runt-related transcription factor 2 levels after a 6-month treatment with recombinant human parathyroid hormone in patients with osteoporosis [J]. Endocrinol Invest,2012, 35(6): 602-606.
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