Effect of low-level laser treatment on cochlea hair-cell recovery after ototoxic hearing loss

Abstract. The primary cause of hearing loss includes damage to cochlear hair cells. Low-level laser therapy (LLLT) has become a popular treatment for damaged nervous systems. Based on the idea that cochlea hair cells and neural cells are from same developmental origin, the effect of LLLT on hearing loss in animal models is evaluated. Hearing loss animal models were established, and the animals were irradiated by 830-nm diode laser once a day for 10 days. Power density of the laser treatment was 900  mW/cm2, and the fluence was 162 to 194 J. The tympanic membrane was evaluated after LLLT. Thresholds of auditory brainstem responses were evaluated before treatment, after gentamicin, and after 10 days of LLLT. Quantitative scanning electron microscopic (SEM) observations were done by counting remaining hair cells. Tympanic membranes were intact at the end of the experiment. No adverse tissue reaction was found. On SEM images, LLLT significantly increased the number of hair cells in middle and basal turns. Hearing was significantly improved by laser irradiation. After LLLT treatment, both the hearing threshold and hair-cell count significantly improved.

[1]  Ji Eun Lee,et al.  Signaling pathway for apoptosis of vestibular hair cells of Mice due to aminoglycosides , 2004, Acta oto-laryngologica. Supplementum.

[2]  Andrea Martins,et al.  Facial scars after a road accident: Combined treatment with PDL and Q‐switched ND:YAG laser , 2008, Journal of cosmetic and laser therapy : official publication of the European Society for Laser Dermatology.

[3]  R P Franke,et al.  Biostimulatory windows in low-intensity laser activation: lasers, scanners, and NASA's light-emitting diode array system. , 2001, Journal of clinical laser medicine & surgery.

[4]  H. Sohmer,et al.  Development of Inner Ear (Cochlear and Vestibular) Function in the Fetus-Neonate , 1999, Journal of basic and clinical physiology and pharmacology.

[5]  Peter A Jenkins,et al.  How to report low-level laser therapy (LLLT)/photomedicine dose and beam parameters in clinical and laboratory studies. , 2011, Photomedicine and laser surgery.

[6]  Kunio Awazu,et al.  Effects of near-infra-red laser irradiation on adenosine triphosphate and adenosine diphosphate contents of rat brain tissue , 2002, Neuroscience Letters.

[7]  U. Oron,et al.  Ga-As (808 nm) laser irradiation enhances ATP production in human neuronal cells in culture. , 2007, Photomedicine and laser surgery.

[8]  Amir Oron,et al.  Transcranial application of low‐energy laser irradiation improves neurological deficits in rats following acute stroke , 2006, Lasers in surgery and medicine.

[9]  M. Anniko,et al.  Cytodifferentiation of cochlear hair cells. , 1983, American journal of otolaryngology.

[10]  Edwin W Rubel,et al.  Caspase Activation in Hair Cells of the Mouse Utricle Exposed to Neomycin , 2002, The Journal of Neuroscience.

[11]  Jin-Chul Ahn,et al.  Effect of low-level laser treatment on cochlea hair-cell recovery after acute acoustic trauma. , 2012, Journal of biomedical optics.

[12]  Jin-Chul Ahn,et al.  Effect of Low-Level Laser and FM 1-43 on Prevention of Ototoxicity in Postnatal Organotypic Cultures of Rat Utricles , 2011 .

[13]  F. Chi,et al.  Taurine attenuates aminoglycoside ototoxicity by inhibiting inducible nitric oxide synthase expression in the cochlea , 2008, Neuroreport.

[14]  Jieli Chen,et al.  Low-Level Laser Therapy Applied Transcranially to Rats After Induction of Stroke Significantly Reduces Long-Term Neurological Deficits , 2006, Stroke.

[15]  J. Samet,et al.  Food and Drug Administration , 2007, BMJ : British Medical Journal.

[16]  Anita Saltmarche,et al.  Improved cognitive function after transcranial, light-emitting diode treatments in chronic, traumatic brain injury: two case reports. , 2011, Photomedicine and laser surgery.

[17]  Jin-Chul Ahn,et al.  Effect of low-level laser therapy on cochlear hair cell recovery after gentamicin-induced ototoxicity , 2012, Lasers in Medical Science.

[18]  Jin-Chul Ahn,et al.  A Promotive Effect of Low-Level Laser on Hair Cell Regeneration Following Gentamicin Induced Ototoxicity in Postnatal Organotypic Culture of Rat Utricles , 2007 .

[19]  P. Lapchak,et al.  Transcranial near-infrared light therapy improves motor function following embolic strokes in rabbits: An extended therapeutic window study using continuous and pulse frequency delivery modes , 2007, Neuroscience.

[20]  Britton Chance,et al.  Photobiomodulation Directly Benefits Primary Neurons Functionally Inactivated by Toxins , 2005, Journal of Biological Chemistry.

[21]  Michael R. Hamblin,et al.  Biphasic Dose Response in Low Level Light Therapy , 2009, Dose-response : a publication of International Hormesis Society.

[22]  D. Cotanche,et al.  Genetic and pharmacological intervention for treatment/prevention of hearing loss. , 2008, Journal of communication disorders.

[23]  Ihsan F R Mohammed,et al.  Promotion of regenerative processes in injured peripheral nerve induced by low-level laser therapy. , 2007, Photomedicine and laser surgery.

[24]  Edwin W Rubel,et al.  Hair Cell Death in the Avian Basilar Papilla: Characterization of the in vitro Model and Caspase Activation , 2003, Journal of the Association for Research in Otolaryngology.