Glucocorticoid-induced alterations in titin, nebulin, myosin heavy chain isoform content and viscoelastic properties of rat skeletal muscle


Viscoelastic properties of skeletal muscle are associated with a complex network of cytoskeletal proteins where titin and nebulin play a substantial role. The need for evaluation of muscle viscoelastic properties is widely accepted in clinical use to evaluate the effect of treatment or progression of muscle pathology (atrophy). We tested the hypothesis that the viscoelastic properties (elasticity, tone and stiffness) change in atrophied muscles with concomitant changes in cytoskeletal proteins (titin, nebulin) and contractile protein (myosin heavy chain) proportion. Sixteen 24- week-old male rats of the Wistar strain were randomly allocated to two groups: dexamethasone group treated each day for 10 consecutive days with dexamethasone in order to induce atrophy and control group. Skeletal muscle viscoelastic properties (elasticity, tone and stiffness) were determined using a myotonometer. Titin, nebulin and myosin heavy chain content were quantified using SDS-PAGE electrophoresis. We found that glucocorticoid-induced muscle atrophy is accompanied by reduced elasticity and increased tone and stiffness, with concomitant changes in titin, nebulin and myosin heavy chain con- tent. The elasticity decreased by 10.9% (P < 0.05), tone increased from 26.69 Hz to 37.73 Hz (P < 0.05), and stiffness was significantly lower in dexamethasone group (627.3 N/m vs 758.6 N/m); (P < 0.05). Compared with the control group, the content of titin, nebulin and myosin heavy chain in atrophied muscle was 76.4%, 70.6% and 82.3%, respectively. Our results may lead to a better understanding of the mechanism of muscle atrophy and provide better guidance for rehabilitation practices and help to find rational therapeutic intervention in the future.

Share and Cite:

Aru, M. , Alev, K. , Gapeyeva, H. , Vain, A. , Puhke, R. , Pehme, A. , Kaasik, P. , Selart, A. and Seene, T. (2013) Glucocorticoid-induced alterations in titin, nebulin, myosin heavy chain isoform content and viscoelastic properties of rat skeletal muscle. Advances in Biological Chemistry, 3, 70-75. doi: 10.4236/abc.2013.31009.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] Horowits, R., Kempner, E.S., Bisher, M.E. and Podolsky, R.J. (1986) A physiological role fortitin and nebulin in skeletal muscle. Nature, 323, 160-164. doi:10.1038/323160a0
[2] Wang, K. and Wright, J. (1988) Architecture of the sarcomere matrix of skeletal muscle: Immunoelectron microscopic evidence that suggests a set of parallel inextensible nebulin filaments anchored at the Z line. Journal of Cell Biology, 107, 2199-2212. doi:10.1083/jcb.107.6.2199
[3] Wang, K., McCarter, R., Wright, J., Beverly, J. and Ramirez-Mitchell, R. (1991) Regulation of skeletal muscle stiffness and elasticity by titin isoforms: A test of the segmental extension model of resting tension. Pro ceedings of the National Academy of Sciences of the United States of America, 88, 7101-7105. doi:10.1073/pnas.88.16.7101
[4] Kaasik, P., Seene, T., Umnova, M. and Alev, K. (2000) The mechanism of action of glucocorticoids in the rat skeletal muscle. Baltic Journal of Laboratory Animal Science, 10, 185-193.
[5] Seene, T., Kaasik, P., Pehme, A., Alev, K. and Riso, E.-M. (2003) The effect of glucocorticoids on the myosin heavy chain isoforms’ turnover in skeletal muscle. The Journal of Steroid Biochemistry and Molecular Biology, 86, 201-206. doi:10.1016/j.jsbmb.2003.08.002
[6] Kaasik, P. (2004) Composition and turnover of myo fibrillar proteins in volume—Overtrained and gluco corticoid caused myopathic skeletal muscle. Disserta tiones, Tartu University Press, Tartu.
[7] Kaasik, P., Umnova, M., Pehme, A., Alev, K., Aru, M., Selart, A. and Seene T. (2007) Ageing and dexame thasone associated sarcopenia: Peculiarities of regeneration. The Journal of Steroid Biochemistry and Molecular Biology, 105, 85-90. doi:10.1016/j.jsbmb.2006.11.024
[8] Kasper, C.E. and Xun, L. (2000) Expression of titin in skeletal muscle varies with hind-limb unloading. Bio logical Research for Nursing, 2, 107-115. doi:10.1177/109980040000200204
[9] Toursel, T., Stevens, L., Granzier, H. and Mounier, Y. (2002) Passive tension of rat skeletal soleus muscle fibers: Effects of unloading conditions. Journal of Applied Phy siology, 92, 1465-1472.
[10] Chen, S.P., Sheu, J.R., Lin, A.C., Hsiao, G. and Fong, T.H. (2005) Decline in titin content in rat skeletal muscle after denervation. Muscle and Nerve, 32, 798-807. doi:10.1002/mus.20432
[11] Hunter, R.J., Neagoe, C., J?rvel?inen, H.A., Martin, C.R., Lindros, K.O., Linke, W.A. and Preedy V.R. (2003) Alcohol affects the skeletal muscle proteins, titin and nebulin in male and female rats. The Journal of Nutrition, 133, 1154-1157.
[12] Udaka, J., Ohmori, S., Terui, T., Ohtsuki, I., Ishiwata, S., Kurihara, S. and Fukuda N. (2008) Disuse-induced pre ferential loss of the giant protein titin depresses muscle performance via abnormal sarcomeric organization. Jour nal of General Physiology, 131, 33-41. doi:10.1085/jgp.200709888
[13] Podlubnaia, Z.A., Vikhliantsev, I.M., Mukhina, A.M., Nemirovskaya, T.L. and Shenkman, B.S. (2004) Sar comeric cytoskeletal proteins and myosin phenotype in stretched soleus of hindlimb-suspended rats. Biofizika, 49, 424-429.
[14] Hayashi, K., Tada, O., Higuchi, K. and Ohtsuka, A. (2000) Effects of corticosterone on connectin content and protein breakdown in rat skeletal muscle. Bioscience, Biote chnology, and Biochemistry, 64, 2686-2688. doi:10.1271/bbb.64.2686
[15] Vain, A. (1995) Estimation of the functional state of skeletal muscle. In: Veltnik, P.H. and Boom, H.B.K., Eds., Control of Ambulation Using Functional Neuro muscular Stimulation, University of Twente Press, Ens chede, 51-55.
[16] Bizzini, M. and Mannion, A.F. (2003) Reliability of a new, hand-held device for assessing skeletal muscle stiffness. Clinical Biomechanics, 18, 459-461. doi:10.1016/S0268-0033(03)00042-1
[17] Korhonen, R.K., Vain, A., Vanninen, E., Viir, R. and Jurvelin, J.S. (2005) Can mechanical myotonometry or electromyography be used for the prediction of intra muscular pressure? Physiological Measurement, 26, 951 963. doi:10.1088/0967-3334/26/6/006
[18] Viir, R., Laiho, K., Kramarenko, J. and Mikkelson, M. (2006) Repeatability of trapezius muscle tone assessment by a myometric method. Journal of Mechanics in Medi cine and Biology, 6, 215-228. doi:10.1142/S0219519406001856
[19] Vikhlyantsev, I.M., Podlubnaya, Z.A. and Kozlovskaya, I.B. (2004) New titin isoforms in skeletal muscles of mammals. Doklady Biochemistry and Biophysics, 395, 111-113. doi:10.1023/B:DOBI.0000025559.14249.43
[20] Talmadge, R.J. and Roy, R.R. (1993) Electrophoretic separation of rat skeletal muscle myosin heavy-chain isoforms. Journal of Applied Physiology, 75, 2337-2340.
[21] Kohn, T.A. and Myburgh, K.H. (2006) Electrophoretic separation of human skeletal muscle myosin heavy chain isoforms: The importance of reducing agents. Journal of Physiological Sciences, 56, 355-360. doi:10.2170/physiolsci.RP007706
[22] H?m?l?inen, N. and Pette, D. (1996). Slow-to-fast transitions in myosin expression of ratsoleus muscle by phasic high-frequency stimulation. FEBS Letters, 399, 220 222. doi:10.1016/S0014-5793(96)01325-7
[23] Oakley, B.R., Kirsch, D.R. and Morris, N.R. (1980) A simplified ultrasensitive silver stain for detecting proteins in polyacrylamide gels. Analytical Biochemistry, 105, 361-363. doi:10.1016/0003-2697(80)90470-4
[24] Maruyama, K. (2002) Beta-actinin, cap Z, connectin and titin: What’s in a name? Trends in Biochemical Sciences, 2, 264-266. doi:10.1016/S0968-0004(02)02068-6
[25] Seene, T., Umnova, M. and Kaasik, P. (1999) The exer cise myopathy. In: Lehmann, M., et al., Eds., Overload, Performance Incompetence, and Regeneration in Sport, Kluwer Academic/Plenum Publishers, New York, 119 130. doi:10.1007/978-0-585-34048-7_9

Copyright © 2021 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.