Lasers in Medical Science

, Volume 32, Issue 2, pp 343–349 | Cite as

Effects of different fluences of low-level laser therapy in an experimental model of spinal cord injury in rats

  • Suellen Veronez
  • Lívia AssisEmail author
  • Paula Del Campo
  • Flávia de Oliveira
  • Gláucia de Castro
  • Ana Claudia Muniz Renno
  • Carla Christina Medalha
Original Article


The aim of this study was to evaluate the in vivo response of different fluences of low-level laser therapy (LLLT) on the area of the injury, inflammatory markers, and functional recovery using an experimental model of traumatic spinal cord injury (SCI). Thirty two rats were randomly divided into four experimental groups: control group (CG), laser-treated group 500 J/cm2 (L-500), laser-treated group 750 J/cm2 (L-750), and laser-treated group 1000 J/cm2 (L-1000). SCI was performed by an impactor equipment (between the ninth and tenth thoracic vertebrae), with a pressure of 150 kdyn. Afterwards, the injured region was irradiated daily for seven consecutive sessions, using an 808-nm laser, at the respective fluence of each experimental groups. Motor function and tactile sensitivity were performed on days 1 and 7 post-surgery. Animals were euthanized on the eighth day after injury, and the samples were retrieved for histological and immunohistochemistry analyses. Functional evaluation and tactile sensitivity were improved after LLLT, at the higher fluence. Additionally, LLLT, at 750 and 1000 J/cm2, reduces the lesion volume and modulates the inflammatory process with decrease of CD-68 protein expression. These results suggest that LLLT at higher doses was effective in promoting functional recovery and modulating inflammatory process in the spinal cord of rats after SCI.


Low-level laser therapy Spinal cord injury Neuronal plasticity Wistar 



We would like to acknowledge the contributions of XXXX funding agency XXXX for the financial support of this research.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


There is no funding source.


  1. 1.
    Ando T, Xuan W, Xu T, Dai T, Sharma SK, Kharkwal GB, Huang YY, Wu Q, Whalen MJ, Sato S, Obara M, Hamblin MR (2011) Comparison of therapeutic effects between pulsed and continuous wave 810-nm wavelength laser irradiation for traumatic brain injury in mice. PLoS One 6:e26212. doi: 10.1371/journal.pone.0026212 CrossRefPubMedPubMedCentralGoogle Scholar
  2. 2.
    Prasad A, Sahin M (2012) Can motor volition be extracted from the spinal cord? J Neuroeng Rehabil 9:41. doi: 10.1186/1743-0003-9-41
  3. 3.
    Scivoletto G, Ivanenko Y, Morganti B, Grasso R, Zago M, Lacquaniti F, Ditunno J, Molinari M (2007) Plasticity of spinal centers in spinal cord injury patients: new concepts for gait evaluation and training. Neurorehabil Neural Repair 21:358–365CrossRefPubMedGoogle Scholar
  4. 4.
    Blanes L, Lourenço L, Carmagnani MI, Ferreira LM (2009) Clinical and socio-demographic characteristics of persons with traumatic paraplegia living in São Paulo, Brazil. Arq Neuropsiquiatr 67:388–390CrossRefPubMedGoogle Scholar
  5. 5.
    Lee BB, Cripps RA, Fitzharris M, Wing PC (2014) The global map for traumatic spinal cord injury epidemiology: update 2011, global incidence rate. Spinal Cord 52:110–116. doi: 10.1038/sc.2012.158 CrossRefPubMedGoogle Scholar
  6. 6.
    Nguyen DH, Cho N, Satkunendrarajah K, Austin JW, Wang J, Fehlings MG (2012) Immunoglobulin G (IgG) attenuates neuroinflammation and improves neurobehavioral recovery after cervical spinal cord injury. J Neuroinflammation 21:224. doi: 10.1186/1742-2094-9-224 Google Scholar
  7. 7.
    Min KJ, Jeong HK, Kim B, Hwang DH, Shin HY, Nguyen AT, Kim JH, Jou I, Kim BG, Joe EH (2012) Spatial and temporal correlation in progressive degeneration of neurons and astrocytes in contusion-induced spinal cord injury. J Neuroinflammation 9:100. doi: 10.1186/1742-2094-9-100 CrossRefPubMedPubMedCentralGoogle Scholar
  8. 8.
    Ren Y, Young W (2013) Managing inflammation after spinal cord injury through manipulation of macrophage function. Neural Plast 2013:945034. doi: 10.1155/2013/945034 PubMedPubMedCentralGoogle Scholar
  9. 9.
    Shin T, Ahn M, Moon C, Kim S, Sim KB (2013) Alternatively activated macrophages in spinal cord injury and remission: another mechanism for repair? Mol Neurobiol 47:1011–1019. doi: 10.1007/s12035-013-8398-6 CrossRefPubMedGoogle Scholar
  10. 10.
    Popovich PG, Guan Z, McGaughy V, Fisher L, Hickey WF, Basso DM (2002) The neuropathological and behavioral consequences of intraspinal microglial/macrophage activation. J Neuropathol Exp Neurol 61:623–633CrossRefPubMedGoogle Scholar
  11. 11.
    Pesce JT, Ramalingam TR, Mentink-Kane MM, Wilson MS, El Kasmi KC, Smith AM, Thompson RW, Cheever AW, Murray PJ, Wynn TA (2009) Arginase-1-expressing macrophages suppress Th2 cytokine-driven inflammation and fibrosis. PLoS Pathog 5(4):e1000371. doi: 10.1371/journal.ppat.1000371 CrossRefPubMedPubMedCentralGoogle Scholar
  12. 12.
    Hamblin MR (2010) Introduction to experimental and clinical studies using low-level laser (light) therapy (LLLT). Lasers Surg Med 42:447–449. doi: 10.1002/lsm.20959 CrossRefPubMedPubMedCentralGoogle Scholar
  13. 13.
    Paula AA, Nicolau RA, Lima Mde O, Salgado MA, Cogo JC (2014) Low-intensity laser therapy effect on the recovery of traumatic spinal cord injury. Lasers Med Sci 29:1849–1859. doi: 10.1007/s10103-014-1586-4 CrossRefPubMedGoogle Scholar
  14. 14.
    Piva JA, Abreu EM, Silva Vdos S, Nicolau RA (2011) Effect of low-level laser therapy on the initial stages of tissue repair: basic principles. An Bras Dermatol 86:947–954CrossRefPubMedGoogle Scholar
  15. 15.
    Bossini PS, Rennó AC, Ribeiro DA, Fangel R, Ribeiro AC, Lahoz Mde A, Parizotto NA (2012) Low level laser therapy (830nm) improves bone repair in osteoporotic rats: similar outcomes at two different dosages. Exp Gerontol 47:136–142. doi: 10.1016/j.exger.2011.11.005 CrossRefPubMedGoogle Scholar
  16. 16.
    Wu X, Dmitriev AE, Cardoso MJ, Viers-Costello AG, Borke RC, Streeter J, Anders JJ (2009) 810 nm wavelength light: an effective therapy for transected or contused rat spinal cord. Lasers Surg Med 41:36–41. doi: 10.1002/lsm.20729 CrossRefPubMedGoogle Scholar
  17. 17.
    Byrnes KR, Waynant RW, Ilev IK, Wu X, Barna L, Smith K, Heckert R, Gerst H, Anders JJ (2005) Light promotes regeneration and functional recovery and alters the immune response after spinal cord injury. Lasers Surg Med 36:171–185CrossRefPubMedGoogle Scholar
  18. 18.
    Basso DM (2004) Behavioral testing after spinal cord injury: congruities, complexities, and controversies. J Neurotrauma 21:395–404CrossRefPubMedGoogle Scholar
  19. 19.
    Marsh BC, Astill SL, Utley A, Ichiyama RM (2011) Movement rehabilitation after spinal cord injuries: emerging concepts and future directions. Brain Res Bull 84:327–336. doi: 10.1016/j.brainresbull.2010.07.011 CrossRefPubMedGoogle Scholar
  20. 20.
    Pitcher GM, Ritchie J, Henry JL (1999) Paw withdrawal threshold in the von Frey hair test is influenced by the surface on which the rat stands. J Neurosci Methods 87:185–193CrossRefPubMedGoogle Scholar
  21. 21.
    Cloutier F, Sears-Kraxberger I, Keachie K, Keirstead HS (2013) Immunological demyelination triggers macrophage/microglial cells activation without inducing astrogliosis. Clin Dev Immunol 2013:812456. doi: 10.1155/2013/812456 CrossRefPubMedPubMedCentralGoogle Scholar
  22. 22.
    Byrnes KR, Stoica BA, Fricke S, Di Giovanni S, Faden AI (2007) Cell cycle activation contributes to post-mitotic cell death and secondary damage after spinal cord injury. Brain 130:2977–2992CrossRefPubMedGoogle Scholar
  23. 23.
    Renno AC, McDonnell PA, Parizotto NA, Laakso EL (2007) The effects of laser irradiation on osteoblast and osteosarcoma cell proliferation and differentiation in vitro. Photomed Laser Surg 25:275–280CrossRefPubMedGoogle Scholar
  24. 24.
    Detloff MR, Clark LM, Hutchinson KJ, Kloos AD, Fisher LC, Basso DM (2010) Validity of acute and chronic tactile sensory testing after spinal cord injury in rats. Exp Neurol 225:366–376. doi: 10.1016/j.expneurol.2010.07.009 CrossRefPubMedPubMedCentralGoogle Scholar
  25. 25.
    Giacci MK, Wheeler L, Lovett S, Dishington E, Majda B, Bartlett CA, Thornton E, Harford-Wright E, Leonard A, Vink R, Harvey AR, Provis J, Dunlop SA, Hart NS, Hodgetts S, Natoli R, Van Den Heuvel C, Fitzgerald M (2014) Differential effects of 670 and 830 nm red near infrared irradiation therapy: a comparative study of optic nerve injury, retinal degeneration, traumatic brain and spinal cord injury. PLoS One 9:e104565. doi: 10.1371/journal.pone.0104565 CrossRefPubMedPubMedCentralGoogle Scholar

Copyright information

© Springer-Verlag London 2016

Authors and Affiliations

  • Suellen Veronez
    • 1
  • Lívia Assis
    • 1
    Email author
  • Paula Del Campo
    • 1
  • Flávia de Oliveira
    • 1
  • Gláucia de Castro
    • 1
  • Ana Claudia Muniz Renno
    • 1
  • Carla Christina Medalha
    • 1
  1. 1.Department of BioscienceFederal University of São PauloSantosBrazil

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