Effect of Local Vibration and Passive Exercise on the Hormones and Neurotransmitters of Hypothalamic–Pituitary–Adrenal Axis in Hindlimb Unloading Rats
Astronauts are severely affected by spaceflight-induced bone loss. Mechanical stimulation through exercise inhibits bone resorption and improves bone formation. Exercise and vibration can prevent the degeneration of the musculoskeletal system in tail-suspended rats, and long-term exercise stress will affect endocrine and immune systems that are prone to fatigue. However, the mechanisms through which exercise and vibration affect the endocrine system remain unknown. This study mainly aimed to investigate the changes in the contents of endocrine axis-related hormones and the effects of local vibration and passive exercise on hypothalamic–pituitary–adrenal (HPA) axis-related hormones in tail-suspended rats. A total of 32 Sprague–Dawley rats were randomly distributed into four groups (n = 8 per group): tail suspension (TS), TS + 35Hz vibration, TS + passive exercise, and control. The rats were placed on a passive exercise and local vibration regimen for 21 days. On day 22 of the experiment, the contents of corticotrophin-releasing hormone, adrenocorticotropic hormone, cortisol, and 5-hydroxytryptamine in the rats were quantified with kits in accordance with the manufacturer’s instructions. Histomorphometry was applied to evaluate histological changes in the hypothalamus. Results showed that 35Hz local vibration cannot cause rats to remain in a stressed state and that it might not inhibit the function of the HPA axis. Therefore, we speculate that this local vibration intensity can protect the function of the HPA axis and helps tail-suspended rats to transition from stressed to adaptive state.
KeywordsPassive exercise Vibration Hypothalamic–pituitary–adrenal axis Hormone Hindlimb unloading
This work was funded by grants from Fundamental Research Funds for Central Public Welfare Research Institutes (118009001000160001), China National Key Research and Development Plan Project (No. 2016YFB1101102) and Beijing outstanding young backbone personnel training project (No. 2017000026825G280).
Compliance with Ethical Standards
Conflict of interests
The authors declare that they have no conflict of interest.
All animal treatments were conducted in accordance with the Regulation of Administration of Affairs Concerning Experimental Animals of State Science and Technology Commission of China and were approved by the Animal Care Committee of Beihang University.
- Caren, L.D., Mandel, A.D., Nunes, J.A.: Effect of simulated weightlessness on the immune system in rats. Aviation Space Environ. Med. 51(3), 251–255 (1980)Google Scholar
- del Corral, P., Mahon, A.D., Duncan, G.E., Howe, C.A., Craig, B.W.: The effect of exercise on serum and salivary cortisol in male children. Med. Sci. Sports Exerc. 26(11), 1297–1301 (1994)Google Scholar
- Dudley-Javoroski, S., Petrie, M.A., McHenry, C.L., Amelon, R.E., Saha, P.K., Shields, R.K.: Bone architecture adaptations after spinal cord injury: impact of long-term vibration of a constrained lower limb. Osteoporosis Intern.: J Establ. Result Cooperation Between Eur. Found Osteoporosis Nat. Osteoporosis Found USA 27(3), 1149–1160 (2016). https://doi.org/10.1007/s00198-015-3326-4 CrossRefGoogle Scholar
- Gong, S., Miao, Y.L., Jiao, G.Z., Sun, M.J., Li, H., Lin, J., Luo, M.J., Tan, J.H.: Dynamics and correlation of serum cortisol and corticosterone under different physiological or stressful conditions in mice. Plos ONE 10(2), e0117503 (2015). https://doi.org/10.1371/journal.pone.0117503 CrossRefGoogle Scholar
- Huang, Y., Luan, H., Sun, L., Bi, J., Wang, Y., Fan, Y.: Local vibration enhanced the efficacy of passive exercise on mitigating bone loss in hindlimb unloading rats. Acta Astronautica (2017)Google Scholar
- Ji, H.P., Seo, D.H., Cho, S., Kim, S.H., Eom, S., Han, S.K.: Effects of partial vibration on morphological changes in bone and surrounding muscle of rats under microgravity condition: comparative study by Gender. Micrograv. Sci. Technol. 27(5), 1–8 (2015)Google Scholar
- Lackner, J.R., DiZio, P.: Space adaptation syndrome: multiple etiological factors and individual differences. J. Washington Acad. Sci. Washington DC 81(2), 89–100 (1991)Google Scholar
- Macho L1, K.R., Vigas, M., Nemeth, S., Popova, I., Tigranian, R.A., Noskov, V.B., Serova, L., Grigoriev, I.A.: Effect of space flights on plasma hormone levels in man and in experimental animal. Acta Astronautica (23), 117–121 (1991)Google Scholar
- Macho, L., Kvetnansky, R., Nemeth, S., Fickova, M., Popova, I., Serova, L., Grigoriev, A.I.: Effects of space flight on endocrine system function in experimental animals. Environ. Med.: Ann. Report Res. Inst. Environ. Med. Nagoya Univ. 40(2), 95–111 (1996)Google Scholar
- Martinez, E.M., Yoshida, M.C., Candelario, T.L., Hughes-Fulford, M.: Spaceflight and simulated microgravity cause a significant reduction of key gene expression in early T-cell activation. Amer. J Physiol. Regul. Integ. Comp. Physiol. 308(6), R480–R488 (2015). https://doi.org/10.1152/ajpregu.00449.2014 CrossRefGoogle Scholar
- Musumeci, G.: The use of vibration as physical exercise and therapy 2(2) (2017)Google Scholar
- Musumeci, G., Loreto, C., Leonardi, R., Castorina, S., Giunta, S., Carnazza, M.L., Trovato, F.M., Pichler, K., Weinberg, A.M.: The effects of physical activity on apoptosis and lubricin expression in articular cartilage in rats with glucocorticoid-induced osteoporosis. J Bone Miner. Metab. 31(3), 274–284 (2013)CrossRefGoogle Scholar
- Pichler, K., Loreto, C., Leonardi, R., Reuber, T., Weinberg, A.M., Musumeci, G.: RANKL Is downregulated in bone cells by physical activity (treadmill and vibration stimulation training) in rat with glucocorticoid-induced osteoporosis. Histol. Histopathol. 28(9), 1185 (2013)Google Scholar
- Ritzmann, R., Krause, A., Freyler, K., Gollhofer, A.: Gravity and neuronal adaptation. Neurophysiology of reflexes from hypo- to hypergravity conditions. Micrograv. Sci. Technol., 29 (2017)Google Scholar
- Riviere, D.: Physiological changes in microgravity. Bulletin de l’Academie nationale de medecine 193(7), 1633–1644 (2009)Google Scholar
- Schneider, S., Askew, C.D., Brummer, V., Kleinert, J., Guardiera, S., Abel, T., Struder, H.K.: The effect of parabolic flight on perceived physical, motivational and psychological state in men and women: correlation with neuroendocrine stress parameters and electrocortical activity. Stress (Amsterdam Netherlands) 12(4), 336–349 (2009). https://doi.org/10.1080/10253890802499175 CrossRefGoogle Scholar
- Si, S., Song, S., Hua, N., Han, H., Xu, B., Wang, G., Zhang, C., Wu, W.: [Combined simulated weightlessness and noise affect cell cycles and composition in rat thymocytes]. Xi bao yu fen zi mian yi xue za zhi = Chin. J Cell Molecul. Immunol. 32(3), 304–307 (2016)Google Scholar
- Xie Minhao, Y.Y., Zhang, Y.: Sports Endocrinology. Beijing Sport University Press, Beijing (2008)Google Scholar