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Moro C, Valverde A, Dole M, Hoh Kam J, Hamilton C, Liebert A, Bicknell B, Benabid AL, Magistretti P, Mitrofanis J. The effect of photobiomodulation on the brain during wakefulness and sleep. Front Neurosci 2022; 16:942536. [PMID: 35968381 PMCID: PMC9366035 DOI: 10.3389/fnins.2022.942536] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 07/08/2022] [Indexed: 11/26/2022] Open
Abstract
Over the last seventy years or so, many previous studies have shown that photobiomodulation, the use of red to near infrared light on body tissues, can improve central and peripheral neuronal function and survival in both health and in disease. These improvements are thought to arise principally from an impact of photobiomodulation on mitochondrial and non-mitochondrial mechanisms in a range of different cell types, including neurones. This impact has downstream effects on many stimulatory and protective genes. An often-neglected feature of nearly all of these improvements is that they have been induced during the state of wakefulness. Recent studies have shown that when applied during the state of sleep, photobiomodulation can also be of benefit, but in a different way, by improving the flow of cerebrospinal fluid and the clearance of toxic waste-products from the brain. In this review, we consider the potential differential effects of photobiomodulation dependent on the state of arousal. We speculate that the effects of photobiomodulation is on different cells and systems depending on whether it is applied during wakefulness or sleep, that it may follow a circadian rhythm. We speculate further that the arousal-dependent photobiomodulation effects are mediated principally through a biophoton – ultra-weak light emission – network of communication and repair across the brain.
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Affiliation(s)
- Cecile Moro
- FDD and CEA-LETI, Clinatec, Université Grenoble Alpes, Grenoble, France
| | - Audrey Valverde
- FDD and CEA-LETI, Clinatec, Université Grenoble Alpes, Grenoble, France
| | - Marjorie Dole
- FDD and CEA-LETI, Clinatec, Université Grenoble Alpes, Grenoble, France
| | - Jaimie Hoh Kam
- FDD and CEA-LETI, Clinatec, Université Grenoble Alpes, Grenoble, France
| | | | - Ann Liebert
- Governance and Research Department, Sydney Adventist Hospital, Sydney, NSW, Australia
| | - Brian Bicknell
- Faculty of Health Sciences, Australian Catholic University, Sydney, NSW, Australia
| | | | - Pierre Magistretti
- FDD and CEA-LETI, Clinatec, Université Grenoble Alpes, Grenoble, France
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - John Mitrofanis
- FDD and CEA-LETI, Clinatec, Université Grenoble Alpes, Grenoble, France
- Institute of Ophthalmology, University College London, London, United Kingdom
- *Correspondence: John Mitrofanis,
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The Molecular Mechanism of Retina Light Injury Focusing on Damage from Short Wavelength Light. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:8482149. [PMID: 35498134 PMCID: PMC9042598 DOI: 10.1155/2022/8482149] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 03/31/2022] [Indexed: 12/30/2022]
Abstract
Natural visible light is an electromagnetic wave composed of a spectrum of monochromatic wavelengths, each with a characteristic color. Photons are the basic units of light, and their wavelength correlates to the energy of light; short-wavelength photons carry high energy. The retina is a fragile neuronal tissue that senses light and generates visual signals conducted to the brain. However, excessive and intensive light exposure will cause retinal light damage. Within the visible spectrum, short-wavelength light, such as blue light, carries higher energy, and thus the retinal injury, is more significant when exposed to these wavelengths. The damage mechanism triggered by different short-wavelength light varies due to photons carrying different energy and being absorbed by different photosensitive molecules in the retinal neurons. However, photooxidation might be a common molecular step to initiate cell death. Herein, we summarize the historical understanding of light, the key molecular steps related to retinal light injury, and the death pathways of photoreceptors to further decipher the molecular mechanism of retinal light injury and explore potential neuroprotective strategies.
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Ji MH, Kreymerman A, Belle K, Ghiam BK, Muscat SR, Mahajan VB, Enns GM, Mercola M, Wood EH. The Present and Future of Mitochondrial-Based Therapeutics for Eye Disease. Transl Vis Sci Technol 2021; 10:4. [PMID: 34232272 PMCID: PMC8267180 DOI: 10.1167/tvst.10.8.4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Translational Relevance Mitochondria are viable therapeutic targets for a broad spectrum of ocular diseases.
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Affiliation(s)
- Marco H Ji
- Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Alexander Kreymerman
- Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, USA.,Stanford Cardiovascular Institute, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Kinsley Belle
- Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Benjamin K Ghiam
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, OH, USA
| | - Stephanie R Muscat
- Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Vinit B Mahajan
- Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Gregory M Enns
- Department of Pediatrics, Division of Medical Genetics, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Mark Mercola
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Edward H Wood
- Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, USA.,Stanford Cardiovascular Institute, Stanford University School of Medicine, Palo Alto, CA, USA
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Ao J, Chidlow G, Wood JPM, Casson RJ. Safety Profile of Slit-Lamp-Delivered Retinal Laser Photobiomodulation. Transl Vis Sci Technol 2020; 9:22. [PMID: 32818109 PMCID: PMC7396177 DOI: 10.1167/tvst.9.4.22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 01/10/2020] [Indexed: 01/15/2023] Open
Abstract
Purpose Photobiomodulation (PBM) refers to therapeutic irradiation of tissue with low-energy, 630- to 1000-nm wavelength light. An increasing body of evidence supports a beneficial effect of PBM in retinal disorders. To date, most studies have utilized light-emitting diode irradiation sources. Slit-lamp-mounted retinal lasers produce a coherent beam that can be delivered with precisely defined dosages and predetermined target area; however, the use of retinal lasers raises safety concerns that warrant investigation prior to clinical application. In this study, we determined safe dosages of laser-delivered PBM to the retina. Methods A custom-designed, slit-lamp-delivered, 670-nm, red/near-infrared laser was used to administer a range of irradiances to healthy pigmented and non-pigmented rat retinas. The effects of PBM on various functional and structural parameters of the retina were evaluated utilizing a combination of electroretinography, Spectral Domain Optical Coherence (SD-OCT), fluorescein angiography, histology and immunohistochemistry. Results In non-pigmented rats, no adverse events were identified at any irradiances up to 500 mW/cm2. In pigmented rats, no adverse events were identified at irradiances of 25 or 100 mW/cm2; however, approximately one-third of rats that received 500 mW/cm2 displayed very localized photoreceptor damage in the peripapillary region, typically adjacent to the optic nerve head. Conclusions A safety threshold exists for laser-delivered PBM in pigmented retinas and was identified as 500 mW/cm2 irradiance; therefore, caution should be exercised in the dosage of laser-delivered PBM administered to pigmented retinas. Translational Relevance This study provides important data necessary for clinical translation of laser-delivered PBM for retinal diseases.
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Affiliation(s)
- Jack Ao
- Ophthalmic Research Laboratories, Discipline of Ophthalmology and Visual Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - Glyn Chidlow
- Ophthalmic Research Laboratories, Discipline of Ophthalmology and Visual Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - John P M Wood
- Ophthalmic Research Laboratories, Discipline of Ophthalmology and Visual Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - Robert J Casson
- Ophthalmic Research Laboratories, Discipline of Ophthalmology and Visual Sciences, University of Adelaide, Adelaide, South Australia, Australia
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Kent AL, Abdel-Latif ME, Cochrane T, Broom M, Dahlstrom JE, Essex RW, Shadbolt B, Natoli R. A pilot randomised clinical trial of 670 nm red light for reducing retinopathy of prematurity. Pediatr Res 2020; 87:131-136. [PMID: 31430763 DOI: 10.1038/s41390-019-0520-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 07/03/2019] [Accepted: 07/10/2019] [Indexed: 11/09/2022]
Abstract
BACKGROUND Photobiomodulation by 670 nm red light in animal models reduced severity of ROP and improved survival. This pilot randomised controlled trial aimed to provide data on 670 nm red light exposure for prevention of ROP and survival for a larger randomised trial. METHODS Neonates <30 weeks gestation or <1150 g at birth were randomised to receive 670 nm for 15 min (9 J/cm2) daily until 34 weeks corrected age. DATA COLLECTED placental pathology, growth, days of respiratory support and oxygen, bronchopulmonary dysplasia, patent ductus arteriosus, necrotising enterocolitis, sepsis, worst stage of ROP, need for laser treatment, and survival. RESULTS Eighty-six neonates enrolled-45 no red light; 41 red light. There was no difference in severity of ROP (<27 weeks-p = 0.463; ≥27 weeks-p = 0.558) or requirement for laser treatment (<27 weeks-p = 1.00; ≥27 weeks-no laser treatment in either group). Survival in 670 nm red light treatment group was 100% (41/41) vs 89% (40/45) in untreated infants (p = 0.057). CONCLUSION Randomisation to receive 670 nm red light within 24-48 h after birth is feasible. Although no improvement in ROP or survivability was observed, further testing into the dosage and delivery for this potential therapy are required.
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Affiliation(s)
- Alison L Kent
- Division of Neonatology, Golisano Children's Hospital, University of Rochester, Rochester, NY, USA. .,Australian National University Medical School, Canberra, ACT, 2601, Australia.
| | - Mohamed E Abdel-Latif
- Australian National University Medical School, Canberra, ACT, 2601, Australia.,Department of Neonatology, Centenary Hospital for Women and Children, Canberra Hospital, Woden, ACT, 2606, Australia
| | - Timothy Cochrane
- Australian National University Medical School, Canberra, ACT, 2601, Australia.,Department of Neonatology, Centenary Hospital for Women and Children, Canberra Hospital, Woden, ACT, 2606, Australia
| | - Margaret Broom
- Department of Neonatology, Centenary Hospital for Women and Children, Canberra Hospital, Woden, ACT, 2606, Australia
| | - Jane E Dahlstrom
- Australian National University Medical School, Canberra, ACT, 2601, Australia.,Department of Anatomical Pathology, Canberra Hospital, Woden, ACT, 2606, Australia.,John Curtin School of Medical Research, College of Medicine Biology and Environment, ANU, Canberra, ACT, 2601, Australia
| | - Rohan W Essex
- Australian National University Medical School, Canberra, ACT, 2601, Australia.,Department of Ophthalmology, Canberra Hospital, Woden, ACT, 2606, Australia
| | - Bruce Shadbolt
- Australian National University Medical School, Canberra, ACT, 2601, Australia.,Clinical Epidemiology, Canberra Hospital, Woden, ACT, 2606, Australia
| | - Riccardo Natoli
- Australian National University Medical School, Canberra, ACT, 2601, Australia.,John Curtin School of Medical Research, College of Medicine Biology and Environment, ANU, Canberra, ACT, 2601, Australia
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Ashworth BE, Stephens E, Bartlett CA, Serghiou S, Giacci MK, Williams A, Hart NS, Fitzgerald M. Comparative assessment of phototherapy protocols for reduction of oxidative stress in partially transected spinal cord slices undergoing secondary degeneration. BMC Neurosci 2016; 17:21. [PMID: 27194427 PMCID: PMC4872332 DOI: 10.1186/s12868-016-0259-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Accepted: 05/11/2016] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Red/near-infrared light therapy (R/NIR-LT) has been developed as a treatment for a range of conditions, including injury to the central nervous system (CNS). However, clinical trials have reported variable or sub-optimal outcomes, possibly because there are few optimized treatment protocols for the different target tissues. Moreover, the low absolute, and wavelength dependent, transmission of light by tissues overlying the target site make accurate dosing problematic. RESULTS In order to optimize light therapy treatment parameters, we adapted a mouse spinal cord organotypic culture model to the rat, and characterized myelination and oxidative stress following a partial transection injury. The ex vivo model allows a more accurate assessment of the relative effect of different illumination wavelengths (adjusted for equal quantal intensity) on the target tissue. Using this model, we assessed oxidative stress following treatment with four different wavelengths of light: 450 nm (blue); 510 nm (green); 660 nm (red) or 860 nm (infrared) at three different intensities: 1.93 × 10(16) (low); 3.85 × 10(16) (intermediate) and 7.70 × 10(16) (high) photons/cm(2)/s. We demonstrate that the most effective of the tested wavelengths to reduce immunoreactivity of the oxidative stress indicator 3-nitrotyrosine (3NT) was 660 nm. 860 nm also provided beneficial effects at all tested intensities, significantly reducing oxidative stress levels relative to control (p ≤ 0.05). CONCLUSIONS Our results indicate that R/NIR-LT is an effective antioxidant therapy, and indicate that effective wavelengths and ranges of intensities of treatment can be adapted for a variety of CNS injuries and conditions, depending upon the transmission properties of the tissue to be treated.
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Affiliation(s)
- Bethany Eve Ashworth
- />Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, WA Australia
- />Department of Biology and Biochemistry, The University of Bath, Bath, UK
| | - Emma Stephens
- />Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, WA Australia
- />Department of Biology and Biochemistry, The University of Bath, Bath, UK
| | - Carole A. Bartlett
- />Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, WA Australia
| | - Stylianos Serghiou
- />Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, UK
| | - Marcus K. Giacci
- />Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, WA Australia
| | - Anna Williams
- />Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, UK
| | - Nathan S. Hart
- />Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, WA Australia
- />Department of Biological Sciences, Macquarie University, Sydney, NSW 2109 Australia
| | - Melinda Fitzgerald
- />Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, WA Australia
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7
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Eells JT, Gopalakrishnan S, Valter K. Near-Infrared Photobiomodulation in Retinal Injury and Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 854:437-41. [PMID: 26427443 DOI: 10.1007/978-3-319-17121-0_58] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Evidence is growing that exposure of tissue to low energy photon irradiation in the far-red (FR) to near-infrared (NIR) range of the spectrum, collectively termed "photobiomodulation" (PBM) can restore the function of damaged mitochondria, upregulate the production of cytoprotective factors and prevent apoptotic cell death. PBM has been applied clinically in the treatment of soft tissue injuries and acceleration of wound healing for more than 40 years. Recent studies have demonstrated that FR/NIR photons penetrate diseased tissues including the retina. The therapeutic effects of PBM have been hypothesized to result from intracellular signaling pathways triggered when FR/NIR photons are absorbed by the mitochondrial photoacceptor molecule, cytochrome c oxidase, culminating in improved mitochondrial energy metabolism, increased cytoprotective factor production and cell survival. Investigations in rodent models of methanol-induced ocular toxicity, light damage, retinitis pigmentosa and age-related macular degeneration have demonstrated the PBM attenuates photoreceptor cell death, protects retinal function and exerts anti-inflammatory actions.
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Affiliation(s)
- Janis T Eells
- Department of Biomedical Sciences, University of Wisconsin-Milwaukee, 2400 E. Hartford Ave., 53201, Milwaukee, WI, USA.
| | | | - Krisztina Valter
- Divsion of Biomedical Sciences, Research School of Biology, Australian National University, 0200, Acton, Australia.
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8
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Kent AL, Broom M, Parr V, Essex RW, Abdel-Latif ME, Dahlstrom JE, Valter K, Provis J, Natoli R. A safety and feasibility study of the use of 670 nm red light in premature neonates. J Perinatol 2015; 35:493-6. [PMID: 25695843 DOI: 10.1038/jp.2015.5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 01/08/2015] [Accepted: 01/12/2015] [Indexed: 11/09/2022]
Abstract
OBJECTIVE Retinopathy of prematurity (ROP) is a vasoproliferative disorder of the retina affecting extremely preterm or low birth weight infants The aim of this study was to assess the feasibility and safety of 670 nm red light use in a neonatal intensive care unit. STUDY DESIGN Neonates <30 weeks gestation and <1150 g were enrolled within 48 h of birth. Data collected included cause of preterm delivery, Apgar scores and birthweight. 670 nm red light was administered for 15 min per day from a distance of 25 cm, delivering 9 J cm(-)(2), from the time of inclusion in the study until 34 weeks postmenstrual age. Infants were assessed daily for the presence of any skin burns or other adverse signs. RESULT Twenty-eight neonates were enrolled, seven 24 to 26 weeks and twenty-one 27 to 29 weeks gestation. The most common cause for preterm delivery was preterm labor (14/28) with five of these having evidence of chorioamnionitis. There were no skin burns or other documented adverse events. Entry into the study was readily achieved and treatment was well accepted by parents and nursing staff. CONCLUSION 670 nm red light appears to be a safe and feasible treatment for further research in respect to ROP.
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Affiliation(s)
- A L Kent
- 1] Department of Neonatology, Canberra Hospital, Woden, ACT, Australia [2] Australian National University Medical School, Canberra, ACT, Australia
| | - M Broom
- Department of Neonatology, Canberra Hospital, Woden, ACT, Australia
| | - V Parr
- Department of Neonatology, Canberra Hospital, Woden, ACT, Australia
| | - R W Essex
- 1] Australian National University Medical School, Canberra, ACT, Australia [2] Department of Ophthalmology, Canberra Hospital, Woden, ACT, Australia
| | - M E Abdel-Latif
- 1] Department of Neonatology, Canberra Hospital, Woden, ACT, Australia [2] Australian National University Medical School, Canberra, ACT, Australia
| | - J E Dahlstrom
- 1] Australian National University Medical School, Canberra, ACT, Australia [2] Department of Anatomical Pathology, Canberra Hospital, Woden, ACT, Australia
| | - K Valter
- 1] Australian National University Medical School, Canberra, ACT, Australia [2] John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - J Provis
- 1] Australian National University Medical School, Canberra, ACT, Australia [2] John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - R Natoli
- 1] Australian National University Medical School, Canberra, ACT, Australia [2] John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
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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. 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 2014; 9:e104565. [PMID: 25105800 PMCID: PMC4126771 DOI: 10.1371/journal.pone.0104565] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 07/10/2014] [Indexed: 01/23/2023] Open
Abstract
Red/near-infrared irradiation therapy (R/NIR-IT) delivered by laser or light-emitting diode (LED) has improved functional outcomes in a range of CNS injuries. However, translation of R/NIR-IT to the clinic for treatment of neurotrauma has been hampered by lack of comparative information regarding the degree of penetration of the delivered irradiation to the injury site and the optimal treatment parameters for different CNS injuries. We compared the treatment efficacy of R/NIR-IT at 670 nm and 830 nm, provided by narrow-band LED arrays adjusted to produce equal irradiance, in four in vivo rat models of CNS injury: partial optic nerve transection, light-induced retinal degeneration, traumatic brain injury (TBI) and spinal cord injury (SCI). The number of photons of 670 nm or 830 nm light reaching the SCI injury site was 6.6% and 11.3% of emitted light respectively. Treatment of rats with 670 nm R/NIR-IT following partial optic nerve transection significantly increased the number of visual responses at 7 days after injury (P ≤ 0.05); 830 nm R/NIR-IT was partially effective. 670 nm R/NIR-IT also significantly reduced reactive species and both 670 nm and 830 nm R/NIR-IT reduced hydroxynonenal immunoreactivity (P ≤ 0.05) in this model. Pre-treatment of light-induced retinal degeneration with 670 nm R/NIR-IT significantly reduced the number of Tunel+ cells and 8-hydroxyguanosine immunoreactivity (P ≤ 0.05); outcomes in 830 nm R/NIR-IT treated animals were not significantly different to controls. Treatment of fluid-percussion TBI with 670 nm or 830 nm R/NIR-IT did not result in improvements in motor or sensory function or lesion size at 7 days (P>0.05). Similarly, treatment of contusive SCI with 670 nm or 830 nm R/NIR-IT did not result in significant improvements in functional recovery or reduced cyst size at 28 days (P>0.05). Outcomes from this comparative study indicate that it will be necessary to optimise delivery devices, wavelength, intensity and duration of R/NIR-IT individually for different CNS injury types.
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Affiliation(s)
- Marcus K. Giacci
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Australia
- School of Animal Biology, The University of Western Australia, Crawley, Australia
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Australia
| | - Lachlan Wheeler
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Australia
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Australia
| | - Sarah Lovett
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Australia
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Australia
| | - Emma Dishington
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Australia
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Australia
| | - Bernadette Majda
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Australia
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Australia
| | - Carole A. Bartlett
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Australia
- School of Animal Biology, The University of Western Australia, Crawley, Australia
| | - Emma Thornton
- School of Medical Sciences, The University of Adelaide, Adelaide, Australia
| | | | - Anna Leonard
- School of Medical Sciences, The University of Adelaide, Adelaide, Australia
| | - Robert Vink
- School of Medical Sciences, The University of Adelaide, Adelaide, Australia
| | - Alan R. Harvey
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Australia
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Australia
| | - Jan Provis
- ANU Medical School and John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Sarah A. Dunlop
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Australia
- School of Animal Biology, The University of Western Australia, Crawley, Australia
| | - Nathan S. Hart
- School of Animal Biology, The University of Western Australia, Crawley, Australia
- Neuroecology Group, The Oceans Institute, The University of Western Australia, Crawley, Australia
| | - Stuart Hodgetts
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Australia
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Australia
| | - Riccardo Natoli
- ANU Medical School and John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | | | - Melinda Fitzgerald
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Australia
- School of Animal Biology, The University of Western Australia, Crawley, Australia
- * E-mail:
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Tang J, Du Y, Lee CA, Talahalli R, Eells JT, Kern TS. Low-intensity far-red light inhibits early lesions that contribute to diabetic retinopathy: in vivo and in vitro. Invest Ophthalmol Vis Sci 2013; 54:3681-90. [PMID: 23557732 DOI: 10.1167/iovs.12-11018] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
PURPOSE Treatment with light in the far-red to near-infrared region of the spectrum (photobiomodulation [PBM]) has beneficial effects in tissue injury. We investigated the therapeutic efficacy of 670-nm PBM in rodent and cultured cell models of diabetic retinopathy. METHODS Studies were conducted in streptozotocin-induced diabetic rats and in cultured retinal cells. Diabetes-induced retinal abnormalities were assessed functionally, biochemically, and histologically in vivo and in vitro. RESULTS We observed beneficial effects of PBM on the neural and vascular elements of retina. Daily 670-nm PBM treatment (6 J/cm(2)) resulted in significant inhibition in the diabetes-induced death of retinal ganglion cells, as well as a 50% improvement of the ERG amplitude (photopic b wave responses) (both P < 0.01). To explore the mechanism for these beneficial effects, we examined physiologic and molecular changes related to cell survival, oxidative stress, and inflammation. PBM did not alter cytochrome oxidase activity in the retina or in cultured retinal cells. PBM inhibited diabetes-induced superoxide production and preserved MnSOD expression in vivo. Diabetes significantly increased both leukostasis and expression of ICAM-1, and PBM essentially prevented both of these abnormalities. In cultured retinal cells, 30-mM glucose exposure increased superoxide production, inflammatory biomarker expression, and cell death. PBM inhibited all of these abnormalities. CONCLUSIONS PBM ameliorated lesions of diabetic retinopathy in vivo and reduced oxidative stress and cell death in vitro. PBM has been documented to have minimal risk. PBM is noninvasive, inexpensive, and easy to administer. We conclude that PBM is a simple adjunct therapy to attenuate the development of diabetic retinopathy.
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Affiliation(s)
- Johnny Tang
- Case Western Reserve University, Cleveland, OH 44106, USA
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