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Zhu M, Liu Y, Fang D, Li M, Fu T, Yao K, Wang P, Sun X, Xiang Y. Safety of repeated low-level red-light therapy for children with myopia. Photodiagnosis Photodyn Ther 2024; 47:104198. [PMID: 38729232 DOI: 10.1016/j.pdpdt.2024.104198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 05/05/2024] [Accepted: 05/06/2024] [Indexed: 05/12/2024]
Abstract
BACKGROUD To investigate the safety of repetitive low-level red-light therapy (RLRLT) in children with myopia. METHODS Children with myopia were assigned to the RLRL and control groups. Axial length (AL) and spherical equivalent refraction (SER) were followed up at 3-, 6-, and 12-month. To evaluate the safety of RLRLT, at 6 and 12 months in the RLRL group, multifocal electroretinography (mfERG) and contrast sensitivity were recorded. Furthermore, optical coherence tomography was used to measure the relative reflectance of the ellipsoid zone (rEZR), photoreceptor outer segment (rPOSR), and retinal pigment epithelium (rRPER). RESULTS A total of 108 children completed the trial (55 in the RLRL group and 53 in the control group). After 3, 6, and 12 months, AL was shorter and SER less myopic in the RLRL group than in the control group. Regarding the safety of the RLRLT, the response density and amplitude of the P1 wave of the first ring of the mfERG increased significantly at 6 months (P = 0.001 and P = 0.017, respectively). At 6 and 12 months, contrast sensitivity at the high spatial frequency increased. Moreover, the rEZR increased significantly at 6 months (P = 0.029), the rPOSR increased significantly at 6 and 12 months (both P < 0.001), and the increase in rPOSR was greater with greater AL regression. CONCLUSIONS Based on retinal function and structure follow-up, RLRLT was safe within 12 months. However, rEZR and rPOSR increased, the effects of this phenomenon requires further observation.
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Affiliation(s)
- Mengxia Zhu
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong, University of Science and Technology, Wuhan, 430030, China
| | - Ying Liu
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong, University of Science and Technology, Wuhan, 430030, China
| | - Dengqin Fang
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong, University of Science and Technology, Wuhan, 430030, China
| | - Mu Li
- Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong, University of Science and Technology, Wuhan, 430030, China
| | - Ting Fu
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong, University of Science and Technology, Wuhan, 430030, China
| | - KeJun Yao
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong, University of Science and Technology, Wuhan, 430030, China
| | - Ping Wang
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong, University of Science and Technology, Wuhan, 430030, China
| | - Xufang Sun
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong, University of Science and Technology, Wuhan, 430030, China
| | - Yan Xiang
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong, University of Science and Technology, Wuhan, 430030, China.
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Anita L, Choi MJ, Yin GN, Ock J, Kwon MH, Rho BY, Chung DY, Suh JK, Ryu JK. Photobiomodulation as a Potential Therapy for Erectile Function: A Preclinical Study in a Cavernous Nerve Injury Model. World J Mens Health 2024; 42:42.e48. [PMID: 38772533 DOI: 10.5534/wjmh.230187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 11/10/2023] [Accepted: 11/19/2023] [Indexed: 05/23/2024] Open
Abstract
PURPOSE To identify the optimal photobiomodulation (PBM) parameters using molecular, histological, and erectile function analysis in cavernous nerve injury. MATERIALS AND METHODS A cavernous nerve injury was induced in 8-week-old C57BL/6J male mice that were subsequently divided randomly into age-matched control groups. Erectile function tests, penile histology, and Western blotting were performed 2 weeks after surgery and PBM treatment. RESULTS The PBM treatment was administered for five consecutive days with a light-emitted diode (LED) device that delivers 660 nm±3% RED light, and near infra-red 830 nm±2% promptly administered following nerve-crushing surgery and achieved a notable restoration of erectile function approximately 90% of the control values. Subsequent in-vitro and ex-vivo analyses revealed the regeneration of neurovascular connections in both the dorsal root ganglion and major pelvic ganglion, characterized by the sprouting of neurites. Furthermore, the expression levels of neurotrophic, survival, and angiogenic factors exhibited a substantial increase across all groups subjected to PBM treatment. CONCLUSIONS The utilization of PBM employing LED with 660 nm, 830 nm, and combination of both these wavelengths, exhibited significant efficacy to restore erectile function in a murine model of cavernous nerve injury. Thus, the PBM emerges as a potent therapeutic modality with notable advantages such as efficacy, noninvasiveness, and non-pharmacological interventions for erectile dysfunction caused by nerve injury.
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Affiliation(s)
- Limanjaya Anita
- Department of Urology and National Research Center for Sexual Medicine, Inha University College of Medicine, Incheon, Korea
| | - Min-Ji Choi
- Department of Urology and National Research Center for Sexual Medicine, Inha University College of Medicine, Incheon, Korea
| | - Guo Nan Yin
- Department of Urology and National Research Center for Sexual Medicine, Inha University College of Medicine, Incheon, Korea
| | - JiYeon Ock
- Department of Urology and National Research Center for Sexual Medicine, Inha University College of Medicine, Incheon, Korea
| | - Mi-Hye Kwon
- Department of Urology and National Research Center for Sexual Medicine, Inha University College of Medicine, Incheon, Korea
| | - Beom Yong Rho
- Department of Urology and National Research Center for Sexual Medicine, Inha University College of Medicine, Incheon, Korea
| | - Doo Yong Chung
- Department of Urology and National Research Center for Sexual Medicine, Inha University College of Medicine, Incheon, Korea
| | - Jun-Kyu Suh
- Department of Urology and National Research Center for Sexual Medicine, Inha University College of Medicine, Incheon, Korea.
| | - Ji-Kan Ryu
- Department of Urology and National Research Center for Sexual Medicine, Inha University College of Medicine, Incheon, Korea.
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Tu X, Xiong C, Qi H, Ou Y, Rao J, Sun Y, Fan Y, Liu G. Diagnosis and treatment of transnasal endoscopic optic canal decompression for traumatic optic neuropathy. Front Neurosci 2023; 17:1168962. [PMID: 37260841 PMCID: PMC10228362 DOI: 10.3389/fnins.2023.1168962] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Accepted: 04/12/2023] [Indexed: 06/02/2023] Open
Abstract
Objective To investigate the clinical efficacy and prognostic factors of transnasal endoscopic optic decompression in the treatment of traumatic optic neuropathy (TON). Methods A retrospective analysis was performed on 13 TON patients in The Seventh Affiliated Hospital of Sun Yat-sen University and Shenzhen Eye Hospital in Shenzhen City (China) from June 2020 to April 2022. These patients had received transnasal endoscopic optic decompression, and hormonal and neurotrophic drugs were given after surgery. Visual acuity (VA) improvement was used as the criterion to judge clinical efficacy. Results In a total of 13 patients, 13 injured eyes (12 men and 1 woman; mean age, 28.0 ± 11.8 years) received transnasal endoscopic optic decompression. After surgery, nine patients had improved VA, whereas four patients failed to show any improvement, resulting in a total effective rate of 69.2%. Of the six patients with no light perception preoperatively, three had effective results after the operation, giving an effective rate of 50.0%. Of the seven patients with residual light sensation preoperatively, six had effective results after the operation, giving an effective rate of 85.7%. Of the 10 patients operated on within 7 days after injury, seven had effective results, giving an effective rate of 70%. Of the three patients injured and operated on after 7 days, two had effective results, giving an effective rate of 66.7%. Conclusion Transnasal endoscopic optic nerve decompression is an effective treatment method for TON. The presence of residual light perception and the timing of surgery within 7 days are crucial to the prognosis.
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Affiliation(s)
- Xiang Tu
- Department of Otolaryngology, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, China
| | - Cheng Xiong
- The Department of Orbital Disease and Ophthalmic Oncology, Shenzhen Eye Hospital, Shenzhen Eye Institute, Jinan University, Shenzhen, China
| | - Hui Qi
- Department of Otolaryngology, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, China
| | - Yangming Ou
- The Department of Orbital Disease and Ophthalmic Oncology, Shenzhen Eye Hospital, Shenzhen Eye Institute, Jinan University, Shenzhen, China
| | - Jing Rao
- The Department of Orbital Disease and Ophthalmic Oncology, Shenzhen Eye Hospital, Shenzhen Eye Institute, Jinan University, Shenzhen, China
| | - Yueqi Sun
- Department of Otolaryngology, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, China
| | - Yunping Fan
- Department of Otolaryngology, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, China
| | - Guiqin Liu
- The Department of Orbital Disease and Ophthalmic Oncology, Shenzhen Eye Hospital, Shenzhen Eye Institute, Jinan University, Shenzhen, China
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Stevens AR, Hadis M, Milward M, Ahmed Z, Belli A, Palin W, Davies DJ. Photobiomodulation in Acute Traumatic Brain Injury: A Systematic Review and Meta-Analysis. J Neurotrauma 2023; 40:210-227. [PMID: 35698294 DOI: 10.1089/neu.2022.0140] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Photobiomodulation (PBM) is a therapeutic modality that has gained increasing interest in neuroscience applications, including acute traumatic brain injury (TBI). Its proposed mechanisms for therapeutic effect when delivered to the injured brain include antiapoptotic and anti-inflammatory effects. This systematic review summarizes the available evidence for the value of PBM in improving outcomes in acute TBI and presents a meta-analysis of the pre-clinical evidence for neurological severity score (NSS) and lesion size in animal models of TBI. A systematic review of the literature was performed, with searches and data extraction performed independently in duplicate by two authors. Eighteen published articles were identified for inclusion: seventeen pre-clinical studies of in vivo animal models and one clinical study in human patients. The available human study supports safety and feasibility of PBM in acute moderate TBI. For pre-clinical studies, meta-analysis for NSS and lesion size were found to favor intervention versus control. Subgroup analysis based on PBM parameter variables for these outcomes was performed. Favorable parameters were identified as: wavelengths in the region of 665 nm and 810 nm; time to first administration of PBM ≤4 h; total number of daily treatments ≤3. No differences were identified between pulsed and continuous wave modes or energy delivery. Mechanistic substudies within included in vivo studies are presented and were found to support hypotheses of antiapoptotic, anti-inflammatory, and pro-proliferative effects, and a modulation of cellular metabolism. This systematic review provides substantial meta-analysis evidence of the benefits of PBM on functional and histological outcomes of TBI in in vivo mammalian models. Study design and PBM parameters should be closely considered for future human clinical studies.
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Affiliation(s)
- Andrew Robert Stevens
- Department of Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, and University of Birmingham, Edgbaston, Birmingham, United Kingdom.,NIHR Surgical Reconstruction and Microbiology Research Centre, University Hospitals Birmingham, Birmingham, United Kingdom.,Phototherapy Research Group, School of Dentistry, University of Birmingham, Birmingham, United Kingdom
| | - Mohammed Hadis
- Phototherapy Research Group, School of Dentistry, University of Birmingham, Birmingham, United Kingdom
| | - Michael Milward
- Phototherapy Research Group, School of Dentistry, University of Birmingham, Birmingham, United Kingdom
| | - Zubair Ahmed
- Department of Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, and University of Birmingham, Edgbaston, Birmingham, United Kingdom.,NIHR Surgical Reconstruction and Microbiology Research Centre, University Hospitals Birmingham, Birmingham, United Kingdom.,Centre for Trauma Sciences Research, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Antonio Belli
- Department of Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, and University of Birmingham, Edgbaston, Birmingham, United Kingdom.,NIHR Surgical Reconstruction and Microbiology Research Centre, University Hospitals Birmingham, Birmingham, United Kingdom.,Centre for Trauma Sciences Research, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - William Palin
- Phototherapy Research Group, School of Dentistry, University of Birmingham, Birmingham, United Kingdom
| | - David James Davies
- Department of Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, and University of Birmingham, Edgbaston, Birmingham, United Kingdom.,NIHR Surgical Reconstruction and Microbiology Research Centre, University Hospitals Birmingham, Birmingham, United Kingdom.,Phototherapy Research Group, School of Dentistry, University of Birmingham, Birmingham, United Kingdom.,Centre for Trauma Sciences Research, University of Birmingham, Edgbaston, Birmingham, United Kingdom
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Saylan A, Firat T, Yis OM. Effects of photobiomodulation therapy on human sperm function. Rev Int Androl 2023; 21:100340. [PMID: 36610824 DOI: 10.1016/j.androl.2022.04.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 03/17/2022] [Accepted: 04/12/2022] [Indexed: 01/07/2023]
Abstract
INTRODUCTION Sperm motility is a crucial factor in male infertility and it depends on mitochondrial tail movements. Photobiomodulation light therapy allows the cells to produce their energy through activation of the mitochondria. The aim of the present study was to examine the impact of photobiomodulation on sperm motility in astenozoospermic individuals. MATERIALS AND METHODS Following semen analyses of 20 astenozoospermic individuals, collected semen samples were centrifuged. Pellet was obtained and homogenized through mixing with culture media in 1:1 ratio. Each semen samples were divided into 3 groups. In the first group, control samples were not exposed to laser irradiation. The Group 2 and Group 3 were exposed to 650nm wavelength of photobiomodulation from 10cm distance in dark environment via a 36cm2 aperture sizer with 200mW output power for 30 and 60min duration, respectively. Sperm motilities were evaluated and chromatin condensation of sperms was determined. RESULTS Sperm motilities were significantly increased in photobiomodulation groups compared with the controls. Sperm motilities tended to be different between the 30 and 60min red light exposure groups; however, it was not statistically significant. When the motility grades were compared, no significant difference was observed in non-progressive motility sperms. While immotile sperms decreased significantly in the photobiomodulation groups compared to the control group, progressive sperms increased. CONCLUSIONS The results of the present study demonstrated that the photobiomodulation is an efficient method to increase the sperm motility of astenozoospermic individuals independent of the duration of exposure.
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Affiliation(s)
- Aslihan Saylan
- Bolu Abant Izzet Baysal University Medical Faculty, Histology and Embryology Department, Bolu, Turkey.
| | - Tulin Firat
- Bolu Abant Izzet Baysal University Medical Faculty, Histology and Embryology Department, Bolu, Turkey
| | - Ozgur Mehmet Yis
- Bolu Abant Izzet Baysal University Medical Faculty, Biochemistry Department, Bolu, Turkey
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Jha KA, Rasiah PK, Gentry J, Del Mar NA, Kumar R, Adebiyi A, Reiner A, Gangaraju R. Mesenchymal stem cell secretome protects against oxidative stress-induced ocular blast visual pathologies. Exp Eye Res 2022; 215:108930. [PMID: 35016886 DOI: 10.1016/j.exer.2022.108930] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 12/16/2021] [Accepted: 01/04/2022] [Indexed: 12/20/2022]
Abstract
Visual deficits are a common concern among subjects with head trauma. Stem cell therapies have gained recent attention in treating visual deficits following head trauma. Previously, we have shown that adipose-derived stem cell (ASC) concentrated conditioned medium (ASC-CCM), when delivered via an intravitreal route, yielded a significant improvement in vision accompanied by a decrease in retinal neuroinflammation in a focal cranial blast model that indirectly injures the retina. The purpose of the current study is to extend our previous studies to a direct ocular blast injury model to further establish the preclinical efficacy of ASC-CCM. Adult C57BL/6J mice were subjected to repetitive ocular blast injury (rOBI) of 25 psi to the left eye, followed by intravitreal delivery of ASC-CCM (∼200 ng protein/2 μl) or saline within 2-3 h. Visual function and histological changes were measured 4 weeks after injury and treatment. In vitro, Müller cells were used to evaluate the antioxidant effect of ASC-CCM. Visual acuity, contrast sensitivity, and b-wave amplitudes in rOBI mice receiving saline were significantly decreased compared with age-matched sham blast mice. Immunohistological analyses demonstrated a significant increase in glial fibrillary acidic protein (a retinal injury marker) in Müller cell processes, DNA/RNA damage, and nitrotyrosine (indicative of oxidative stress) in the retina, while qPCR analysis revealed a >2-fold increase in pro-inflammatory cytokines (TNF-α, ICAM1, and Ccl2) in the retina, as well as markers for microglia/macrophage activation (IL-1β and CD86). Remarkably, rOBI mice that received ASC-CCM demonstrated a significant improvement in visual function compared to saline-treated rOBI mice, with visual acuity, contrast sensitivity, and b-wave amplitudes that were not different from those in sham mice. This improvement in visual function also was associated with a significant reduction in retinal GFAP, neuroinflammation markers, and oxidative stress compared to saline-treated rOBI mice. In vitro, Müller cells exposed to oxidative stress via increasing doses of hydrogen peroxide demonstrated decreased viability, increased GFAP mRNA expression, and reduced activity for the antioxidant catalase. On the other hand, oxidatively stressed Müller cells pre-incubated with ASC-CCM showed normalized GFAP, viability, and catalase activity. In conclusion, our study demonstrates that a single intravitreal injection of ASC-CCM in the rOBI can significantly rescue retinal injury and provide significant restoration of visual function. Our in vitro studies suggest that the antioxidant catalase may play a major role in the protective effects of ASC-CCM, uncovering yet another aspect of the multifaceted benefits of ASC secretome therapies in neurotrauma.
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Affiliation(s)
- Kumar Abhiram Jha
- Department of Ophthalmology, University of Tennessee Health Science Center, 930 Madison Ave, Suite 769, Memphis, TN, 38163, USA.
| | - Pratheepa Kumari Rasiah
- Department of Ophthalmology, University of Tennessee Health Science Center, 930 Madison Ave, Suite 769, Memphis, TN, 38163, USA.
| | - Jordy Gentry
- Department of Ophthalmology, University of Tennessee Health Science Center, 930 Madison Ave, Suite 769, Memphis, TN, 38163, USA.
| | - Nobel A Del Mar
- Department of Anatomy & Neurobiology, University of Tennessee Health Science Center, 317 Wittenborg Building, 875 Monroe Avenue, Memphis, TN, 38163, USA.
| | - Ravi Kumar
- Department of Physiology, University of Tennessee Health Science Center, 956 Court Avenue, Coleman Building, Suite C211, Memphis, TN, 38163, USA.
| | - Adebowale Adebiyi
- Department of Physiology, University of Tennessee Health Science Center, 956 Court Avenue, Coleman Building, Suite C211, Memphis, TN, 38163, USA.
| | - Anton Reiner
- Department of Anatomy & Neurobiology, University of Tennessee Health Science Center, 522 Wittenborg Building, 875 Monroe Avenue, Memphis, TN, 38163, USA.
| | - Rajashekhar Gangaraju
- Department of Ophthalmology, Anatomy & Neurobiology, Neuroscience Institute, University of Tennessee Health Science Center, 930 Madison Ave, Suite 768, Memphis, TN, 38163, USA.
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Ayar Z, Gholami B, Piri SM, Kaveh M, Baigi V, Ghodsi Z, Hassannejad Z, Rahimi-Movaghar V. The effect of low-level laser therapy on pathophysiology and locomotor recovery after traumatic spinal cord injuries: a systematic review and meta-analysis. Lasers Med Sci 2021; 37:61-75. [PMID: 33791887 DOI: 10.1007/s10103-021-03301-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Accepted: 03/22/2021] [Indexed: 12/30/2022]
Abstract
This study was designed to determine the effective therapeutic parameters and evaluate the regenerative potential of low-level laser therapy (LLLT) after traumatic spinal cord injuries (TSCIs) in animal studies. The EMBASE and MEDLINE databases were searched on October 5, 2019, and followed with an update on January 2, 2021. All animal studies discussing the effect of LLLT on main pathophysiological events after TSCI, including inflammation, axon growth, remyelination, glial scar formation, cavity size, and locomotor recovery, were included. For statistical analysis, we used mean difference with 95% confidence intervals for locomotor recovery. In total, 19 articles were included based on our criteria. The results showed that regardless of laser type, laser beams with a wavelength between 600 and 850 nm significantly suppress inflammation and led inflammatory cells to M2 polarization and wound healing. Also, laser therapy using these wavelengths for more than 2 weeks significantly improved axon regeneration and remyelination. Improvement of locomotor recovery was more efficient using wavelengths less than 700 nm (SMD = 1.21; 95%CI: 0.09, 2.33; p = 0.03), lasers with energy densities less than 100 J/cm2 (SMD = 1.72; 95%CI: 0.84, 2.59; p = 0.0001) and treatment duration between 1 and 2 weeks (SMD = 2.21; 95%CI: 1.24, 3.19; p < 0.00001). The LLLT showed promising potential to modulate pathophysiological events and recovery after TSCI, although there was heterogeneity in study design and reporting methods, which should be considered in future studies.
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Affiliation(s)
- Zahra Ayar
- Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
| | - Bahareh Gholami
- Sina Trauma and Surgery Research Center, Sina Hospital, Tehran University of Medical Sciences, Hassan-Abad Square, Imam Khomeini Ave, Tehran, 11365-3876, Iran
| | - Seyed Mohammad Piri
- Sina Trauma and Surgery Research Center, Sina Hospital, Tehran University of Medical Sciences, Hassan-Abad Square, Imam Khomeini Ave, Tehran, 11365-3876, Iran
| | - Meysam Kaveh
- Sina Trauma and Surgery Research Center, Sina Hospital, Tehran University of Medical Sciences, Hassan-Abad Square, Imam Khomeini Ave, Tehran, 11365-3876, Iran
| | - Vali Baigi
- Sina Trauma and Surgery Research Center, Sina Hospital, Tehran University of Medical Sciences, Hassan-Abad Square, Imam Khomeini Ave, Tehran, 11365-3876, Iran
| | - Zahra Ghodsi
- Sina Trauma and Surgery Research Center, Sina Hospital, Tehran University of Medical Sciences, Hassan-Abad Square, Imam Khomeini Ave, Tehran, 11365-3876, Iran
| | - Zahra Hassannejad
- Pediatric Urology and Regenerative Medicine Research Center, Children's Medical Center, Tehran University of Medical Sciences, No. 62, Dr. Gharib's Street, Keshavarz Boulevard, Tehran, 1419733151, Iran.
| | - Vafa Rahimi-Movaghar
- Sina Trauma and Surgery Research Center, Sina Hospital, Tehran University of Medical Sciences, Hassan-Abad Square, Imam Khomeini Ave, Tehran, 11365-3876, Iran.
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8
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Shah EJ, Hüttemann M, Sanderson TH, Gurdziel K, Ruden DM. Inhibiting Mitochondrial Cytochrome c Oxidase Downregulates Gene Transcription After Traumatic Brain Injury in Drosophila. Front Physiol 2021; 12:628777. [PMID: 33790803 PMCID: PMC8005633 DOI: 10.3389/fphys.2021.628777] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 02/23/2021] [Indexed: 12/13/2022] Open
Abstract
Traumatic brain injuries (TBIs) caused by a sudden impact to the head alter behavior and impair physical and cognitive function. Besides the severity, type and area of the brain affected, the outcome of TBI is also influenced by the patient’s biological sex. Previous studies reporting mitochondrial dysfunction mainly focused on exponential reactive oxygen species (ROS) generation, increased mitochondrial membrane potential, and altered mitochondrial dynamics as a key player in the outcome to brain injury. In this study, we evaluated the effect of a near-infrared (NIR) light exposure on gene expression in a Drosophila TBI model. NIR interacts with cytochrome c oxidase (COX) of the electron transport chain to reduce mitochondrial membrane potential hyperpolarization, attenuate ROS generation, and apoptosis. We subjected w1118 male and female flies to TBI using a high-impact trauma (HIT) device and subsequently exposed the isolated fly brains to a COX-inhibitory wavelength of 750 nm for 2 hours (hr). Genome-wide 3′-mRNA-sequencing of fly brains revealed that injured w1118 females exhibit greater changes in transcription compared to males at 1, 2, and 4 hours (hr) after TBI. Inhibiting COX by exposure to NIR downregulates gene expression in injured females but has minimal effect in injured males. Our results suggest that mitochondrial COX modulation with NIR alters gene expression in Drosophila following TBI and the response to injury and NIR exposure varies by biological sex.
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Affiliation(s)
- Ekta J Shah
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI, United States
| | - Maik Hüttemann
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, United States
| | - Thomas H Sanderson
- Department of Emergency Medicine, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Katherine Gurdziel
- Office of the Vice President of Research, Wayne State University, Detroit, MI, United States
| | - Douglas M Ruden
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI, United States.,Institute of Environmental Health Sciences, Wayne State University, Detroit, MI, United States.,Department of Obstetrics and Gynecology, Wayne State University, Detroit, MI, United States
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9
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Analgesic Effects of Constant and Frequency-Modulated LED-Generated Red Polarized Light. NEUROPHYSIOLOGY+ 2021. [DOI: 10.1007/s11062-021-09882-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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10
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Morse PT, Goebel DJ, Wan J, Tuck S, Hakim L, Hüttemann CL, Malek MH, Lee I, Sanderson TH, Hüttemann M. Cytochrome c oxidase-modulatory near-infrared light penetration into the human brain: Implications for the noninvasive treatment of ischemia/reperfusion injury. IUBMB Life 2020; 73:554-567. [PMID: 33166061 DOI: 10.1002/iub.2405] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 10/05/2020] [Accepted: 10/23/2020] [Indexed: 11/10/2022]
Abstract
Near-infrared light (IRL) has been evaluated as a therapeutic for a variety of pathological conditions, including ischemia/reperfusion injury of the brain, which can be caused by an ischemic stroke or cardiac arrest. Strategies have focused on modulating the activity of mitochondrial electron transport chain (ETC) enzyme cytochrome c oxidase (COX), which has copper centers that broadly absorb IRL between 700 and 1,000 nm. We have recently identified specific COX-inhibitory IRL wavelengths that are profoundly neuroprotective in rodent models of brain ischemia/reperfusion through the following mechanism: COX inhibition by IRL limits mitochondrial membrane potential hyperpolarization during reperfusion, which otherwise causes reactive oxygen species (ROS) production and cell death. Prior to clinical application of IRL on humans, IRL penetration must be tested, which may be wavelength dependent. In the present study, four fresh (unfixed) cadavers and isolated cadaver tissues were used to examine the transmission of infrared light through human biological tissues. We conclude that the transmission of 750 and 940 nm IRL through 4 cm of cadaver head supports the viability of IRL to treat human brain ischemia/reperfusion injury and is similar for skin with different skin pigmentation. We discuss experimental difficulties of working with fresh cadavers and strategies to overcome them as a guide for future studies.
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Affiliation(s)
- Paul T Morse
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, Michigan, USA
| | - Dennis J Goebel
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University, Detroit, Michigan, USA
| | - Junmei Wan
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, Michigan, USA
| | - Samuel Tuck
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, Michigan, USA.,Department of Emergency Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Lara Hakim
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, Michigan, USA
| | - Charlotte L Hüttemann
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, Michigan, USA
| | - Moh H Malek
- Department of Health Care Sciences, Eugene Applebaum College of Pharmacy & Health Sciences, Wayne State University, Detroit, Michigan, USA
| | - Icksoo Lee
- College of Medicine, Dankook University, Cheonan-si, Republic of Korea
| | - Thomas H Sanderson
- Department of Emergency Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Maik Hüttemann
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, Michigan, USA.,Department of Biochemistry, Microbiology and Immunology, Wayne State University, Detroit, Michigan, USA
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Ramezani F, Razmgir M, Tanha K, Nasirinezhad F, Neshastehriz A, Bahrami-Ahmadi A, Hamblin MR, Janzadeh A. Photobiomodulation for spinal cord injury: A systematic review and meta-analysis. Physiol Behav 2020; 224:112977. [DOI: 10.1016/j.physbeh.2020.112977] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 04/05/2020] [Accepted: 05/19/2020] [Indexed: 01/29/2023]
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12
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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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13
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Photobiomodulation Mediates Neuroprotection against Blue Light Induced Retinal Photoreceptor Degeneration. Int J Mol Sci 2020; 21:ijms21072370. [PMID: 32235464 PMCID: PMC7177783 DOI: 10.3390/ijms21072370] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 03/21/2020] [Accepted: 03/27/2020] [Indexed: 12/12/2022] Open
Abstract
Potent neuroprotective effects of photobiomodulation with 670 nm red light (RL) have been demonstrated in several models of retinal disease. RL improves mitochondrial metabolism, reduces retinal inflammation and oxidative cell stress, showing its ability to enhance visual function. However, the current knowledge is limited to the main hypothesis that the respiratory chain complex IV, cytochrome c oxidase, serves as the primary target of RL. Here, we demonstrate a comprehensive cellular, molecular, and functional characterization of neuroprotective effects of 670 nm RL and 810 nm near-infrared light (NIRL) on blue light damaged murine primary photoreceptors. We show that respiratory chain complexes I and II are additional PBM targets, besides complex IV, leading to enhanced mitochondrial energy metabolism. Accordingly, our study identified mitochondria related RL- and NIRL-triggered defense mechanisms promoting photoreceptor neuroprotection. The observed improvement of mitochondrial and extramitochondrial respiration in both inner and outer segments is linked with reduced oxidative stress including its cellular consequences and reduced mitochondria-induced apoptosis. Analysis of regulatory mechanisms using gene expression analysis identified upregulation α-crystallins that indicate enhanced production of proteins with protective functions that point to the rescued mitochondrial function. The results support the hypothesis that energy metabolism is a major target for retinal light therapy.
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Hu D, van Zeyl M, Valter K, Potas JR. Sex, but not skin tone affects penetration of red-light (660 nm) through sites susceptible to sports injury in lean live and cadaveric tissues. JOURNAL OF BIOPHOTONICS 2019; 12:e201900010. [PMID: 30851081 DOI: 10.1002/jbio.201900010] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 02/06/2019] [Accepted: 03/07/2019] [Indexed: 06/09/2023]
Abstract
Red-light treatment is emerging as a novel therapy for promoting tissue recovery but data on red-light penetration through human tissues are lacking. We aimed to: (1) determine the effect of light irradiance, tissue thickness, skin tone, sex and bone/muscle content on 660 nm light penetration through common sites of sports injuries, and (2) establish if cadaver tissues serve as a useful model for predicting red-light penetration in live tissues. Live and cadaver human tissues were exposed to 660 nm light at locations across the skull, spinal cord and upper and lower limbs. Red-light was produced by a light emitting diode array of various irradiances (15-500 mW/cm2 ) and measured by a light-probe positioned on the tissue surface opposite to the light emitting diodes. 100 mW/cm2 successfully penetrated tissue <50 mm thick; a disproportionate irradiance increase was required to achieve deeper penetration. Penetration was unaffected by skin tone, increased with irradiance and relative bone/muscle composition, and decreased with greater tissue thickness and in males. Live and cadaveric tissue penetration did not differ statistically for tissues <50 mm but cadavers required more red-light to penetrate >50 mm. These results assist clinicians and researchers in determining red-light treatment intensities for penetrating human tissues.
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Affiliation(s)
- Di Hu
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Marc van Zeyl
- ANU Medical School, The Australian National University, Canberra, Australia
| | - Krisztina Valter
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
- ANU Medical School, The Australian National University, Canberra, Australia
| | - Jason R Potas
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
- ANU Medical School, The Australian National University, Canberra, Australia
- School of Medical Sciences, UNSW Sydney, Sydney, New South Wales, Australia
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15
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Shuaib A, Bourisly AK. Photobiomodulation Optimization for Spinal Cord Injury Rat Phantom Model. Transl Neurosci 2018; 9:67-71. [PMID: 29967691 PMCID: PMC6024694 DOI: 10.1515/tnsci-2018-0012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 04/24/2018] [Indexed: 12/20/2022] Open
Abstract
Spinal Cord Injury (SCI) causes interruption along the severed axonal tract(s) resulting in complete or partial loss of sensation and motor function. SCI can cause tetraplegia or paraplegia. Both these conditions can have lifelong excessive medical costs, as well as can reduce life expectancy. Preclinical research showed that Photobiomodulation therapy (PBMT), also known as Low-level laser (light) therapy (LLLT), possesses reparative and regenerative capabilities that have the potential to be used as a complimentary or supplementary SCI therapy. Despite the promising effects of PBMT, there are still no standardized irradiation parameters (i.e. different wavelengths, power, fluence, irradiance, beam type, beam diameters, and irradiation time) and there is also a lack of standardized experimental protocol(s), which makes it difficult to compare different studies. It is, nonetheless, essential to standardize such irradiation parameters in order to provide better PBMTs. The aim of this study, therefore, is to evaluate the delivery of light in a 3D voxelated SCI rat model for PBMT using different irradiation parameters (wavelengths: 660, 810, and 980 nm; beam types: Gaussian and Flat beam; and beam diameters: 0.04-1.2 cm) using Monte Carlo simulation. This study also aids in providing standardization for preclinical research for PBMT, which will eventually translate into clinical standardization upon clinical research studies and results.
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Affiliation(s)
- Ali Shuaib
- Biomedical Engineering Unit, Department of Physiology, Faculty of Medicine, Kuwait University, Kuwait city, Kuwait
| | - Ali K Bourisly
- Biomedical Engineering Unit, Department of Physiology, Faculty of Medicine, Kuwait University, Kuwait city, Kuwait
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16
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670nm light treatment following retinal injury modulates Müller cell gliosis: Evidence from in vivo and in vitro stress models. Exp Eye Res 2018; 169:1-12. [PMID: 29355737 DOI: 10.1016/j.exer.2018.01.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 01/04/2018] [Accepted: 01/12/2018] [Indexed: 11/22/2022]
Abstract
Photobiomodulation (PBM) with 670 nm light has been shown to accelerate wound healing in soft tissue injuries, and also to protect neuronal tissues. However, little data exist on its effects on the non-neuronal components of the retina, such as Müller cells (MCs), which are the principal macroglia of the retina that play a role in maintaining retinal homeostasis. The aim of this study was to explore the effects of 670 nm light on activated MCs using in vivo and in vitro stress models. Adult Sprague-Dawley rats were exposed to photo-oxidative damage (PD) for 24 h and treated with 670 nm light at 0, 3 and 14 days after PD. Tissue was collected at 30 days post-PD for analysis. Using the in vitro scratch model with a human MC line (MIO-M1), area coverage and cellular stress were analysed following treatment with 670 nm light. We showed that early treatment with 670 nm light after PD reduced MC activation, lowering the retinal expression of GFAP and FGF-2. 670 nm light treatment mitigated the production of MC-related pro-inflammatory cytokines (including IL-1β), and reduced microglia/macrophage (MG/MΦ) recruitment into the outer retina following PD. This subsequently decreased photoreceptor loss, slowing the progression of retinal degeneration. In vitro, we showed that 670 nm light directly modulated MC activation, reducing rates of area coverage by suppressing cellular proliferation and spreading. This study indicates that 670 nm light treatment post-injury may have therapeutic benefit when administered shortly after retinal damage, and could be useful for retinal degenerations where MC gliosis is a feature of disease progression.
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Sen N. An insight into the vision impairment following traumatic brain injury. Neurochem Int 2017; 111:103-107. [PMID: 28163060 PMCID: PMC5540824 DOI: 10.1016/j.neuint.2017.01.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 01/20/2017] [Accepted: 01/30/2017] [Indexed: 01/08/2023]
Abstract
Traumatic brain injury (TBI) is one of the major cause of morbidity and mortality and it affects more than 1.7 million Americans each year. Depending on its location and severity, TBI leads to structural and functional damage in several parts of the brain such as cranial nerves, optic nerve tract or other circuitry involved in vision, and occipital lobe. As a result, the function associated with vision processing and perception are significantly affected and cause blurred vision, double vision, decreased peripheral vision and blindness. In this mini-review, we will focus the recent progress made to understand the pathology and underlying cellular/molecular mechanisms involved in the impairment of the integrity of visual systems following TBI.
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Affiliation(s)
- Nilkantha Sen
- Department of Neuroscience and Regenerative Medicine, Augusta University, 1120 15th Street, CA 2018, Augusta, GA 30907, USA.
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18
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Lu YZ, Natoli R, Madigan M, Fernando N, Saxena K, Aggio-Bruce R, Jiao H, Provis J, Valter K. Photobiomodulation with 670 nm light ameliorates Müller cell-mediated activation of microglia and macrophages in retinal degeneration. Exp Eye Res 2017; 165:78-89. [PMID: 28888911 DOI: 10.1016/j.exer.2017.09.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 09/03/2017] [Accepted: 09/05/2017] [Indexed: 12/21/2022]
Abstract
Müller cells, the supporting cells of the retina, play a key role in responding to retinal stress by releasing chemokines, including CCL2, to recruit microglia and macrophages (MG/MΦ) into the damaged retina. Photobiomodulation (PBM) with 670 nm light has been shown to reduce inflammation in models of retinal degeneration. In this study, we aimed to investigate whether 670 nm light had an effect on Müller cell-initiated inflammation under retinal photo-oxidative damage (PD) in vivo and in vitro. Sprague-Dawley rats were pre-treated with 670 nm light (9J/cm2) once daily over 5 days prior to PD. The expression of inflammatory genes including CCL2 and IL-1β was analysed in retinas. In vitro, primary Müller cells dissociated from neonatal rat retinas were co-cultured with 661W photoreceptor cells. Co-cultures were exposed to PD, followed by 670 nm light treatment to the Müller cells only, and Müller cell stress and inflammation were assessed. Primary MG/MΦ were incubated with supernatant from the co-cultures, and collected for analysis of inflammatory activation. To further understand the mechanism of 670 nm light, the expression of COX5a and mitochondrial membrane potential (ΔΨm) were measured in Müller cells. Following PD, 670 nm light-treated Müller cells had a reduced inflammatory activation, with lower levels of CCL2, IL-1β and IL-6. Supernatant from 670 nm light-treated co-cultures reduced activation of primary MG/MΦ, and lowered the expression of pro-inflammatory cytokines, compared to untreated PD controls. Additionally, 670 nm light-treated Müller cells had an increased expression of COX5a and an elevated ΔΨm following PD, suggesting that retrograde signaling plays a role in the effects of 670 nm light on Müller cell gene expression. Our data indicates that 670 nm light reduces Müller cell-mediated retinal inflammation, and offers a potential cellular mechanism for 670 nm light therapy in regulating inflammation associated with retinal degenerations.
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Affiliation(s)
- Yen-Zhen Lu
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Riccardo Natoli
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia; ANU Medical School, The Australian National University, Canberra, ACT, Australia
| | - Michele Madigan
- Save Sight Institute, Discipline of Clinical Ophthalmology, The University of Sydney, Sydney, NSW, Australia; School of Optometry and Vision Science, The University of New South Wales, Kensington, NSW, Australia
| | - Nilisha Fernando
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Kartik Saxena
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Riemke Aggio-Bruce
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Haihan Jiao
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Jan Provis
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia; ANU Medical School, The Australian National University, Canberra, ACT, Australia
| | - Krisztina Valter
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia; ANU Medical School, The Australian National University, Canberra, ACT, Australia.
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Beirne K, Rozanowska M, Votruba M. Photostimulation of mitochondria as a treatment for retinal neurodegeneration. Mitochondrion 2017; 36:85-95. [PMID: 28499983 DOI: 10.1016/j.mito.2017.05.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 02/15/2017] [Accepted: 05/08/2017] [Indexed: 01/01/2023]
Abstract
Absorption of photon energy by neuronal mitochondria leads to numerous downstream neuroprotective effects. Red and near infrared (NIR) light are associated with significantly less safety concerns than light of shorter wavelengths and they are therefore, the optimal choice for irradiating the retina. Potent neuroprotective effects have been demonstrated in various models of retinal damage, by red/NIR light, with limited data from human studies showing its ability to improve visual function. Improved neuronal mitochondrial function, increased blood flow to neural tissue, upregulation of cell survival mediators and restoration of normal microglial function have all been proposed as potential underlying mechanisms of red/NIR light.
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Affiliation(s)
- Kathy Beirne
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK; Cardiff Institute for Tissue Engineering and Repair, Cardiff University, Cardiff, UK.
| | - Malgorzata Rozanowska
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK; Cardiff Institute for Tissue Engineering and Repair, Cardiff University, Cardiff, UK.
| | - Marcela Votruba
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK; Cardiff Institute for Tissue Engineering and Repair, Cardiff University, Cardiff, UK; Cardiff Eye Unit, University Hospital of Wales, Cardiff, UK.
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20
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Reinhart F, Massri NE, Torres N, Chabrol C, Molet J, Johnstone DM, Stone J, Benabid AL, Mitrofanis J, Moro C. The behavioural and neuroprotective outcomes when 670 nm and 810 nm near infrared light are applied together in MPTP-treated mice. Neurosci Res 2017; 117:42-47. [DOI: 10.1016/j.neures.2016.11.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 10/13/2016] [Accepted: 11/15/2016] [Indexed: 01/15/2023]
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21
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Effects of different fluences of low-level laser therapy in an experimental model of spinal cord injury in rats. Lasers Med Sci 2016; 32:343-349. [DOI: 10.1007/s10103-016-2120-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 11/22/2016] [Indexed: 01/12/2023]
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22
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Xuan W, Huang L, Hamblin MR. Repeated transcranial low-level laser therapy for traumatic brain injury in mice: biphasic dose response and long-term treatment outcome. JOURNAL OF BIOPHOTONICS 2016; 9:1263-1272. [PMID: 26990361 PMCID: PMC5025344 DOI: 10.1002/jbio.201500336] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 02/10/2016] [Accepted: 02/11/2016] [Indexed: 05/02/2023]
Abstract
We previously showed that near-infrared laser photobiomodulation (PBM) (810 nm, CW, 18 J/cm2 , 25 mW/cm2 ) delivered to the mouse daily for 3-days after a controlled cortical impact traumatic brain injury (TBI) gave a significant improvement in neurological/cognitive function. However the same parameters delivered 14X daily gave significantly less benefit. This biphasic dose response intrigued us, and we decided to follow the mice that received 3X or 14X laser treatments out to 56-days post-TBI. We found the 14X group showed worse neurological function than the no-treatment TBI group at 2-weeks, but started to improve steadily during the next 6-weeks, and by 56-days were significantly better than the no-treatment TBI mice, but still worse than the 3X mice. A marker of activated glial cells (GFAP) was significantly increased in the brain regions (compared to both untreated TBI and 3X groups) at 4-weeks in the 14X group, but the GFAP had fallen to low levels in both 3X and 14X groups by 8-weeks. We conclude that an excessive number of laser-treatments delivered to mice can temporarily inhibit the process of brain repair stimulated by tPBM, but then the inhibitory effect ceases, and brain repair can resume. The mechanism may be temporary induction of reactive gliosis.
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Affiliation(s)
- Weijun Xuan
- Dept of Otorhinolaryngology, Head and Neck Surgery, Ruikang Clinical Medical College, Guangxi University of Chinese Medicine, Nanning, China
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Dermatology, Harvard Medical School, Boston, MA 02115, USA
| | - Liyi Huang
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Dermatology, Harvard Medical School, Boston, MA 02115, USA
| | - Michael R Hamblin
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Dermatology, Harvard Medical School, Boston, MA 02115, USA
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA 02139, USA
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Hu D, Zhu S, Potas JR. Red LED photobiomodulation reduces pain hypersensitivity and improves sensorimotor function following mild T10 hemicontusion spinal cord injury. J Neuroinflammation 2016; 13:200. [PMID: 27561854 PMCID: PMC5000419 DOI: 10.1186/s12974-016-0679-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2016] [Accepted: 08/17/2016] [Indexed: 12/20/2022] Open
Abstract
Background The development of hypersensitivity following spinal cord injury can result in incurable persistent neuropathic pain. Our objective was to examine the effect of red light therapy on the development of hypersensitivity and sensorimotor function, as well as on microglia/macrophage subpopulations following spinal cord injury. Methods Wistar rats were treated (or sham treated) daily for 30 min with an LED red (670 nm) light source (35 mW/cm2), transcutaneously applied to the dorsal surface, following a mild T10 hemicontusion injury (or sham injury). The development of hypersensitivity was assessed and sensorimotor function established using locomotor recovery and electrophysiology of dorsal column pathways. Immunohistochemistry and TUNEL were performed to examine cellular changes in the spinal cord. Results We demonstrate that red light penetrates through the entire rat spinal cord and significantly reduces signs of hypersensitivity following a mild T10 hemicontusion spinal cord injury. This is accompanied with improved dorsal column pathway functional integrity and locomotor recovery. The functional improvements were preceded by a significant reduction of dying (TUNEL+) cells and activated microglia/macrophages (ED1+) in the spinal cord. The remaining activated microglia/macrophages were predominantly of the anti-inflammatory/wound-healing subpopulation (Arginase1+ED1+) which were expressed early, and up to sevenfold greater than that found in sham-treated animals. Conclusions These findings demonstrate that a simple yet inexpensive treatment regime of red light reduces the development of hypersensitivity along with sensorimotor improvements following spinal cord injury and may therefore offer new hope for a currently treatment-resistant pain condition.
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Affiliation(s)
- Di Hu
- The John Curtin School of Medical Research, The Australian National University, Building 131, Garran Rd, Canberra, ACT 2601, Australia
| | - Shuyu Zhu
- The John Curtin School of Medical Research, The Australian National University, Building 131, Garran Rd, Canberra, ACT 2601, Australia
| | - Jason Robert Potas
- The John Curtin School of Medical Research, The Australian National University, Building 131, Garran Rd, Canberra, ACT 2601, Australia. .,ANU Medical School, The Australian National University, Canberra, ACT 2601, Australia.
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Beirne K, Rozanowska M, Votruba M. Red Light Treatment in an Axotomy Model of Neurodegeneration. Photochem Photobiol 2016; 92:624-31. [DOI: 10.1111/php.12606] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 05/09/2016] [Indexed: 12/21/2022]
Affiliation(s)
- Kathy Beirne
- School of Optometry and Vision Sciences; Cardiff University; Cardiff UK
- Cardiff Institute for Tissue Engineering and Repair; Cardiff University; Cardiff UK
| | - Malgorzata Rozanowska
- School of Optometry and Vision Sciences; Cardiff University; Cardiff UK
- Cardiff Institute for Tissue Engineering and Repair; Cardiff University; Cardiff UK
| | - Marcela Votruba
- School of Optometry and Vision Sciences; Cardiff University; Cardiff UK
- Cardiff Institute for Tissue Engineering and Repair; Cardiff University; Cardiff UK
- Cardiff Eye Unit; University Hospital of Wales; Cardiff UK
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25
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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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Yu J, Luan X, Lan S, Yan B, Maier A. Fasudil, a Rho-Associated Protein Kinase Inhibitor, Attenuates Traumatic Retinal Nerve Injury in Rabbits. J Mol Neurosci 2015; 58:74-82. [DOI: 10.1007/s12031-015-0691-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2015] [Accepted: 11/23/2015] [Indexed: 12/17/2022]
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Yang W, Liu TT, Song XB, Zhang Y, Li ZH, Hao Q, Cui ZH, Liu HL, Lei CL, Liu J. Neuregulin-1 protects against acute optic nerve injury in rat model. J Neurol Sci 2015; 357:157-66. [PMID: 26235969 DOI: 10.1016/j.jns.2015.07.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 06/09/2015] [Accepted: 07/14/2015] [Indexed: 01/23/2023]
Abstract
OBJECTIVES In this study, we employed a rat model and examined the expression pattern of neuregulin-1 (NRG-1) in optic nerve and retinal ganglion cells (RGCs) in response to optic nerve injury to understand the role of NRG-1 in conferring protection against acute optic nerve injury. METHOD Forty-eight male rats were randomly divided into two groups, the sham-operation group (n=24) and optic nerve injury group (n=24). Flash visual evoked potentials (FVEP) and fundography images were acquired at different time points following optic nerve injury (2h, 1d, 2d, 7d, 14d and 28d). Semi-quantitative analysis of NGR-1 expression pattern was performed by immunohistochemistry (IHC) staining. In a related experiment, 100 male rats were randomly divided into NGR-1 treatment group (n=60) (treated with increasing dose of NGR-1 at 0.5μg, 1μg and 3μg), normal saline (NS) group (n=20) and negative control group (n=20). Optic nerve injury was induced in all the animals and in situ cell death was measured by detecting the apoptosis rates using TUNEL assay. RESULTS Fundus photography results revealed no detectable differences between the sham-operation group and optic nerve injury group at 2h, 1d, 2d and 7d. However at 2weeks, the optic discs turned pale in all animals in the optic nerve injury group. NRG-1 expression increased significantly at all time points in the optic nerve injury group (P<0.05), compared to the sham-operation group, with NRG-1 expression peaking at 14d and gradually declining by 28d. Statistically significant differences in amplitude and latency of P100 wave were also detected between the optic nerve injury and sham-operation group (P<0.05). In related experiment, compared to NS group, treatment with 1μg and 3μg of recombinant human NRG-1 resulted in statistically significant FVEP-P100 amplitude values (all P<0.05). Further, compared to the NS group, ganglion cell apoptosis was dramatically reduced in the NRG-1 group at all time points and the reduction was statistically significant in 3μg NRG-1 treatment group at 7d, 14d and 28d (all P<0.05). CONCLUSION Our results strongly suggest that NRG-1 is highly effective in preserving normal optic nerve function and is essential for tissue repair following optic nerve injury. Thus, NRG-1 expression confers protection against acute optic nerve injury in a dose-dependent manner.
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Affiliation(s)
- Wei Yang
- Department of Ophthalmology, The First Hospital of Jilin University, Changchun 130021, PR China
| | - Tao-Tao Liu
- Department of Ophthalmology, The First Hospital of Jilin University, Changchun 130021, PR China
| | - Xiao-Bin Song
- Department of Emergency Surgery, Jilin Province People's Hospital, Changchun 130021, PR China
| | - Yan Zhang
- Department of Otorhinolaryngology, Head and Neck Surgery, The First Hospital of Jilin University, Changchun 130021, PR China
| | - Zhao-Hui Li
- Department of Ophthalmology, People's Hospital of Changchun City, Changchun 130021, PR China
| | - Qian Hao
- Department of Ophthalmology, The First Hospital of Jilin University, Changchun 130021, PR China.
| | - Zhi-Hua Cui
- Department of Ophthalmology, The First Hospital of Jilin University, Changchun 130021, PR China.
| | - Hong Lei Liu
- Department of Ophthalmology, The First Hospital of Jilin University, Changchun 130021, PR China
| | - Chun Ling Lei
- Department of Ophthalmology, The First Hospital of Jilin University, Changchun 130021, PR China
| | - Jun Liu
- Department of Ophthalmology, The First Hospital of Jilin University, Changchun 130021, PR China
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Morries LD, Cassano P, Henderson TA. Treatments for traumatic brain injury with emphasis on transcranial near-infrared laser phototherapy. Neuropsychiatr Dis Treat 2015; 11:2159-75. [PMID: 26347062 PMCID: PMC4550182 DOI: 10.2147/ndt.s65809] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Traumatic brain injury (TBI) is a growing health concern affecting civilians and military personnel. In this review, treatments for the chronic TBI patient are discussed, including pharmaceuticals, nutraceuticals, cognitive therapy, and hyperbaric oxygen therapy. All available literature suggests a marginal benefit with prolonged treatment courses. An emerging modality of treatment is near-infrared (NIR) light, which has benefit in animal models of stroke, spinal cord injury, optic nerve injury, and TBI, and in human trials for stroke and TBI. The extant literature is confounded by variable degrees of efficacy and a bewildering array of treatment parameters. Some data indicate that diodes emitting low-level NIR energy often have failed to demonstrate therapeutic efficacy, perhaps due to failing to deliver sufficient radiant energy to the necessary depth. As part of this review, we present a retrospective case series using high-power NIR laser phototherapy with a Class IV laser to treat TBI. We demonstrate greater clinical efficacy with higher fluence, in contrast to the bimodal model of efficacy previously proposed. In ten patients with chronic TBI (average time since injury 9.3 years) given ten treatments over the course of 2 months using a high-power NIR laser (13.2 W/0.89 cm(2) at 810 nm or 9 W/0.89 cm(2) at 810 nm and 980 nm), symptoms of headache, sleep disturbance, cognition, mood dysregulation, anxiety, and irritability improved. Symptoms were monitored by depression scales and a novel patient diary system specifically designed for this study. NIR light in the power range of 10-15 W at 810 nm and 980 nm can safely and effectively treat chronic symptoms of TBI. The clinical benefit and effects of infrared phototherapy on mitochondrial function and secondary molecular events are discussed in the context of adequate radiant energy penetration.
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Affiliation(s)
| | - Paolo Cassano
- Harvard Medical School, Depression Clinical and Research Program, Massachusetts General Hospital, Boston, MA, USA
| | - Theodore A Henderson
- Neuro-Laser Foundation, Lakewood, CO, USA ; The Synaptic Space, Centennial, CO, USA
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Henderson TA, Morries LD. Near-infrared photonic energy penetration: can infrared phototherapy effectively reach the human brain? Neuropsychiatr Dis Treat 2015. [PMID: 26346298 DOI: 10.2147/ndt] [Citation(s) in RCA: 157] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/15/2023] Open
Abstract
Traumatic brain injury (TBI) is a growing health concern effecting civilians and military personnel. Research has yielded a better understanding of the pathophysiology of TBI, but effective treatments have not been forthcoming. Near-infrared light (NIR) has shown promise in animal models of both TBI and stroke. Yet, it remains unclear if sufficient photonic energy can be delivered to the human brain to yield a beneficial effect. This paper reviews the pathophysiology of TBI and elaborates the physiological effects of NIR in the context of this pathophysiology. Pertinent aspects of the physical properties of NIR, particularly in regards to its interactions with tissue, provide the background for understanding this critical issue of light penetration through tissue. Our recent tissue studies demonstrate no penetration of low level NIR energy through 2 mm of skin or 3 cm of skull and brain. However, at 10-15 W, 0.45%-2.90% of 810 nm light penetrated 3 cm of tissue. A 15 W 810 nm device (continuous or non-pulsed) NIR delivered 2.9% of the surface power density. Pulsing at 10 Hz reduced the dose of light delivered to the surface by 50%, but 2.4% of the surface energy reached the depth of 3 cm. Approximately 1.22% of the energy of 980 nm light at 10-15 W penetrated to 3 cm. These data are reviewed in the context of the literature on low-power NIR penetration, wherein less than half of 1% of the surface energy could reach a depth of 1 cm. NIR in the power range of 10-15 W at 810 and 980 nm can provide fluence within the range shown to be biologically beneficial at 3 cm depth. A companion paper reviews the clinical data on the treatment of patients with chronic TBI in the context of the current literature.
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Affiliation(s)
- Theodore A Henderson
- The Synaptic Space, Centennial, CO, USA ; Neuro-Laser Foundation, Lakewood, CO, USA
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Henderson TA, Morries LD. Near-infrared photonic energy penetration: can infrared phototherapy effectively reach the human brain? Neuropsychiatr Dis Treat 2015; 11:2191-208. [PMID: 26346298 PMCID: PMC4552256 DOI: 10.2147/ndt.s78182] [Citation(s) in RCA: 227] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Traumatic brain injury (TBI) is a growing health concern effecting civilians and military personnel. Research has yielded a better understanding of the pathophysiology of TBI, but effective treatments have not been forthcoming. Near-infrared light (NIR) has shown promise in animal models of both TBI and stroke. Yet, it remains unclear if sufficient photonic energy can be delivered to the human brain to yield a beneficial effect. This paper reviews the pathophysiology of TBI and elaborates the physiological effects of NIR in the context of this pathophysiology. Pertinent aspects of the physical properties of NIR, particularly in regards to its interactions with tissue, provide the background for understanding this critical issue of light penetration through tissue. Our recent tissue studies demonstrate no penetration of low level NIR energy through 2 mm of skin or 3 cm of skull and brain. However, at 10-15 W, 0.45%-2.90% of 810 nm light penetrated 3 cm of tissue. A 15 W 810 nm device (continuous or non-pulsed) NIR delivered 2.9% of the surface power density. Pulsing at 10 Hz reduced the dose of light delivered to the surface by 50%, but 2.4% of the surface energy reached the depth of 3 cm. Approximately 1.22% of the energy of 980 nm light at 10-15 W penetrated to 3 cm. These data are reviewed in the context of the literature on low-power NIR penetration, wherein less than half of 1% of the surface energy could reach a depth of 1 cm. NIR in the power range of 10-15 W at 810 and 980 nm can provide fluence within the range shown to be biologically beneficial at 3 cm depth. A companion paper reviews the clinical data on the treatment of patients with chronic TBI in the context of the current literature.
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Affiliation(s)
- Theodore A Henderson
- The Synaptic Space, Centennial, CO, USA ; Neuro-Laser Foundation, Lakewood, CO, USA
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