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Michael R Hamblin - One of the best experts on this subject based on the ideXlab platform.
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effects of low level Light Therapy and no on Light irradiation efficacy of ruthenium phthalocyanine complexes as a function of radical species formation conference presentation
Mechanisms of Photobiomodulation Therapy XIII, 2018Co-Authors: Laisa Negri, Tassia Martins, Roberto Santana Da Silva, Michael R HamblinAbstract:Different kinds of Light irradiation has been used for several decades in clinical Therapy. Among them low level Light Therapy (LLLT) is found to modulate signaling pathways, via production of ROS, ATP, Ca+2 and NO, which could be an important tool in a combination with other kind of Therapy1. We have found some benefits of the combined LLLT and photodynamic Therapy (PDT) using a metal-based compound, as an alternative treatment that combines photosensitizer, reactive oxygen and nitrogen species (RONS) and Light irradiation against cancer2. Two types of ruthenium compounds were used in those studies ([Ru(Pc)], Pc = phthalocyanine) (I) and [RuNO(Pc)NO2] (II). Herein, we present the synthesis, characterization and photobiological properties of both ruthenium complexes. Both complexes present UV-Vis spectral peaks in 650 nm region. Light irradiation on the Q-band using (II) 0,5 µM provokes a decrease in the percentage of viable cells in human melanoma (A431) around 40 % in comparison to (I). We have hypothesized that those results are coming from the synergistic effect between singlet oxygen and nitric oxide. Similar experiment performed with the combination of PDT (660 nm) +LLLT (850 nm) induced more active photocytotoxicity of (I) and (II), which were interpreted as a function of the increase of cell metabolism and consequently increase of the uptake of the ruthenium-phthalocyanine compounds. The use of metal-based photosensitizers and combination of Light Therapy described in this work maybe constitutes in an advance in the field of clinical work related to photodynamic Therapy.
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proposed mechanisms of photobiomodulation or low level Light Therapy
IEEE Journal of Selected Topics in Quantum Electronics, 2016Co-Authors: Lucas Freitas De Freitas, Michael R HamblinAbstract:Photobiomodulation also known as low-level laser (or Light) Therapy (LLLT), has been known for almost 50 years but still has not gained widespread acceptance, largely due to uncertainty about the molecular, cellular, and tissular mechanisms of action. However, in recent years, much knowledge has been gained in this area, which will be summarized in this review. One of the most important chromophores is cytochrome c oxidase (unit IV in the mitochondrial respiratory chain), which contains both heme and copper centers and absorbs Light into the near-infrared region. The leading hypothesis is that the photons dissociate inhibitory nitric oxide from the enzyme, leading to an increase in electron transport, mitochondrial membrane potential, and adenosine triphosphate production. Another hypothesis concerns Light-sensitive ion channels that can be activated allowing calcium (Ca2+) to enter the cell. After the initial photon absorption events, numerous signaling pathways are activated via reactive oxygen species, cyclic AMP, NO, and Ca2+, leading to activation of transcription factors. These transcription factors can lead to increased expression of genes related to protein synthesis, cell migration and proliferation, anti-inflammatory signaling, anti-apoptotic proteins, and antioxidant enzymes. Stem cells and progenitor cells appear to be particularly susceptible to LLLT.
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antimicrobial blue Light Therapy for candida albicans burn infection in mice
Proceedings of SPIE, 2015Co-Authors: Michael R Hamblin, Clinton K. Murray, Yunsong Zhang, Yucheng Wang, Tianhong DaiAbstract:In this preclinical study, we investigated the utility of antimicrobial blue Light Therapy for Candida albicans infection in acutely burned mice. A bioluminescent strain of C. albicans was used. The susceptibilities to blue Light inactivation were compared between C. albicans and human keratinocyte. In vitro serial passaging of C. albicans on blue Light exposure was performed to evaluate the potential development of resistance to blue Light inactivation. A mouse model of acute thermal burn injury infected with the bioluminescent strain of C. albicans was developed. Blue Light (415 nm) was delivered to mouse burns for decolonization of C. albicans. Bioluminescence imaging was used to monitor in real time the extent of fungal infection in mouse burns. Experimental results showed that C. albicans was approximately 42-fold more susceptible to blue Light inactivation in vitro than human keratinocyte (P=0.0022). Serial passaging of C. albicans on blue Light exposure implied a tendency for the fungal susceptibility to blue Light inactivation to decrease with the numbers of passages. Blue Light reduced fungal burden by over 4-log10 (99.99%) in acute mouse burns infected with C. albicans in comparison to infected mouse burns without blue Light Therapy (P=0.015).
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low level laser Light Therapy and photobiomodulation the path forward
Proceedings of SPIE, 2015Co-Authors: Marcelo Victor Pires De Sousa, Michael R Hamblin, Praveen R Arany, James D Carroll, Donald PatthoffAbstract:Low level laser (Light) Therapy (LLLT) also known as photobiomodulation (PBM) Therapy has been practiced for almost fifty years, and hundreds of positive clinical trials and thousands of laboratory studies have been published. Despite these impressive accomplishments LLLT has still not reached the stage of acceptance by mainstream medicine. The reasons for this were discussed at a recent Optical Society of America (OSA) Incubator meeting in Washington DC in 2014. Uncertainty about mechanisms was highLighted, and this paper will describe the current thinking. To drive LLLT towards mainstream medicine, we need better guidelines with standardized protocols and consistent parameters. Studies should be published in higher impact scientific and medical journals. Companies should avoid false promises and deceptive marketing, and physicians should receive a clearly defined return on investment with insurance reimbursement.
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low level Light Therapy potentiates npe6 mediated photodynamic Therapy in a human osteosarcoma cell line via increased atp
Photodiagnosis and Photodynamic Therapy, 2015Co-Authors: Yingying Huang, Michael R Hamblin, Shangru Tsai, Borching SheuAbstract:Abstract Background Low-level Light Therapy (LLLT) is used to stimulate healing, reduce pain and inflammation, and preserve tissue from dying. LLLT has been shown to protect cells in culture from dying after various cytotoxic insults, and LLLT is known to increase the cellular ATP content. Previous studies have demonstrated that maintaining a sufficiently high ATP level is necessary for the efficient induction and execution of apoptosis steps after photodynamic Therapy (PDT). Methods We asked whether LLLT would protect cells from cytotoxicity due to PDT, or conversely whether LLLT would enhance the efficacy of PDT mediated by mono- l -aspartyl chlorin(e6) (NPe6). Increased ATP could lead to enhanced cell uptake of NPe6 by the energy dependent process of endocytosis, and also to more efficient apoptosis. In this study, human osteosarcoma cell line MG-63 was subjected to 1.5 J/cm2 of 810 nm near infrared radiation (NIR) followed by addition of 10 μM NPe6 and after 2 h incubation by 1.5 J/cm2 of 652 nm red Light for PDT. Results PDT combined with LLLT led to higher cell death and increased intracellular reactive oxygen species compared to PDT alone. The uptake of NPe6 was moderately increased by LLLT, and cellular ATP was increased. The mitochondrial respiratory chain inhibitor antimycin A abrogated the LLLT-induced increase in cytotoxicity. Conclusions Taken together, these results demonstrate that LLLT potentiates NPe6-mediated PDT via increased ATP synthesis and is a potentially promising strategy that could be applied in clinical PDT.
Yingying Huang - One of the best experts on this subject based on the ideXlab platform.
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low level laser Light Therapy increases mitochondrial membrane potential and atp synthesis in c2c12 myotubes with a peak response at 3 6 h
Photochemistry and Photobiology, 2015Co-Authors: Cleber Ferraresi, Beatriz Kaippert, Marcelo Victor Pires De Sousa, Pinar Avci, Yingying Huang, Vanderlei Salvador Bagnato, Nivaldo Antonio ParizottoAbstract:Low-level laser (Light) Therapy has been used before exercise to increase muscle performance in both experimental animals and in humans. However, uncertainty exists concerning the optimum time to apply the Light before exercise. The mechanism of action is thought to be stimulation of mitochondrial respiration in muscles, and to increase adenosine triphosphate (ATP) needed to perform exercise. The goal of this study was to investigate the time course of the increases in mitochondrial membrane potential (MMP) and ATP in myotubes formed from C2C12 mouse muscle cells and exposed to Light-emitting diode Therapy (LEDT). LEDT employed a cluster of LEDs with 20 red (630 ± 10 nm, 25 mW) and 20 near-infrared (850 ± 10 nm, 50 mW) delivering 28 mW cm2 for 90 s (2.5 J cm2) with analysis at 5 min, 3 h, 6 h and 24 h post-LEDT. LEDT-6 h had the highest MMP, followed by LEDT-3 h, LEDT-24 h, LEDT-5 min and Control with significant differences. The same order (6 h > 3 h > 24 h > 5 min > Control) was found for ATP with significant differences. A good correlation was found (r = 0.89) between MMP and ATP. These data suggest an optimum time window of 3–6 h for LEDT stimulate muscle cells.
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low level Light Therapy potentiates npe6 mediated photodynamic Therapy in a human osteosarcoma cell line via increased atp
Photodiagnosis and Photodynamic Therapy, 2015Co-Authors: Yingying Huang, Michael R Hamblin, Shangru Tsai, Borching SheuAbstract:Abstract Background Low-level Light Therapy (LLLT) is used to stimulate healing, reduce pain and inflammation, and preserve tissue from dying. LLLT has been shown to protect cells in culture from dying after various cytotoxic insults, and LLLT is known to increase the cellular ATP content. Previous studies have demonstrated that maintaining a sufficiently high ATP level is necessary for the efficient induction and execution of apoptosis steps after photodynamic Therapy (PDT). Methods We asked whether LLLT would protect cells from cytotoxicity due to PDT, or conversely whether LLLT would enhance the efficacy of PDT mediated by mono- l -aspartyl chlorin(e6) (NPe6). Increased ATP could lead to enhanced cell uptake of NPe6 by the energy dependent process of endocytosis, and also to more efficient apoptosis. In this study, human osteosarcoma cell line MG-63 was subjected to 1.5 J/cm2 of 810 nm near infrared radiation (NIR) followed by addition of 10 μM NPe6 and after 2 h incubation by 1.5 J/cm2 of 652 nm red Light for PDT. Results PDT combined with LLLT led to higher cell death and increased intracellular reactive oxygen species compared to PDT alone. The uptake of NPe6 was moderately increased by LLLT, and cellular ATP was increased. The mitochondrial respiratory chain inhibitor antimycin A abrogated the LLLT-induced increase in cytotoxicity. Conclusions Taken together, these results demonstrate that LLLT potentiates NPe6-mediated PDT via increased ATP synthesis and is a potentially promising strategy that could be applied in clinical PDT.
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time response of increases in atp and muscle resistance to fatigue after low level laser Light Therapy lllt in mice
Lasers in Medical Science, 2015Co-Authors: Cleber Ferraresi, Marcelo Victor Pires De Sousa, Yingying Huang, Nivaldo Antonio Parizotto, Vanderlei Salvador Bagnato, Michael R HamblinAbstract:Recently, low-level laser (Light) Therapy has been used to increase muscle performance in intense exercises. However, there is a lack of understanding of the time response of muscles to Light Therapy. The first purpose of this study was to determine the time response for Light-emitting diode Therapy (LEDT)-mediated increase in adenosine triphosphate (ATP) in the soleus and gastrocnemius muscles in mice. Second purpose was to test whether LEDT can increase the resistance of muscles to fatigue during intense exercise. Fifty male Balb/c mice were randomly allocated into two equal groups: LEDT-ATP and LEDT-fatigue. Both groups were subdivided into five equal subgroups: LEDT-sham, LEDT-5 min, LEDT-3 h, LEDT-6 h, and LEDT-24 h. Each subgroup was analyzed for muscle ATP content or fatigue at specified time after LEDT. The fatigue test was performed by mice repeatedly climbing an inclined ladder bearing a load of 150 % of body weight until exhaustion. LEDT used a cluster of LEDs with 20 red (630 ± 10 nm, 25 mW) and 20 infrared (850 ± 20 nm, 50 mW) delivering 80 mW/cm2 for 90 s (7.2 J/cm2) applied to legs, gluteus, and lower back muscles. LEDT-6 h was the subgroup with the highest ATP content in soleus and gastrocnemius compared to all subgroups (P < 0.001). In addition, mice in LEDT-6 h group performed more repetitions in the fatigue test (P < 0.001) compared to all subgroups: LEDT-sham and LEDT-5 min (~600 %), LEDT-3 h (~200 %), and LEDT-24 h (~300 %). A high correlation between the fatigue test repetitions and the ATP content in soleus (r = 0.84) and gastrocnemius (r = 0.94) muscles was observed. LEDT increased ATP content in muscles and fatigue resistance in mice with a peak at 6 h. Although the time response in mice and humans is not the same, athletes might consider applying LEDT at 6 h before competition.
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antimicrobial blue Light Therapy for multidrug resistant acinetobacter baumannii infection in a mouse burn model implications for prophylaxis and treatment of combat related wound infections
The Journal of Infectious Diseases, 2014Co-Authors: Yingying Huang, Asheesh Gupta, Michael R Hamblin, Clinton K. Murray, Yunsong Zhang, David G Baer, Mark S Vrahas, Margaret E SherwoodAbstract:In this study, we investigated the utility of antimicrobial blue Light Therapy for multidrug-resistant Acinetobacter baumannii infection in a mouse burn model. A bioluminescent clinical isolate of multidrug-resistant A. baumannii was obtained. The susceptibility of A. baumannii to blue Light (415 nm)–inactivation was compared in vitro to that of human keratinocytes. Repeated cycles of sublethal inactivation of bacterial by blue Light were performed to investigate the potential resistance development of A. baumannii to blue Light. A mouse model of third degree burn infected with A. baumannii was developed. A single exposure of blue Light was initiated 30 minutes after bacterial inoculation to inactivate A. baumannii in mouse burns. It was found that the multidrug-resistant A. baumannii strain was significantly more susceptible than keratinocytes to blue Light inactivation. Transmission electron microscopy revealed blue Light–induced ultrastructural damage in A. baumannii cells. Fluorescence spectroscopy suggested that endogenous porphyrins exist in A. baumannii cells. Blue Light at an exposure of 55.8 J/cm2 significantly reduced the bacterial burden in mouse burns. No resistance development to blue Light inactivation was observed in A. baumannii after 10 cycles of sublethal inactivation of bacteria. No significant DNA damage was detected in mouse skin by means of a skin TUNEL assay after a blue Light exposure of 195 J/cm2.
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transcranial low level Light Therapy produces neuroprotection neurogenesis and bdnf after tbi in mice
Proceedings of SPIE, 2013Co-Authors: Fatma Vatansever, Yingying Huang, Michael R Hamblin, Weijun XuanAbstract:We have previously shown that transcranial low level Light Therapy (LLLT) can ameliorate brain damage in mice subjected to traumatic brain injury and improve neurological function. We used a 810-nm laser and delivered 18 J/cm2 at an irradiance 25 mW/cm2. LLLT was either delivered once at 4 hours after controlled cortical impact TBI, once a day for 3 days, or once a day for 14 days. One and 3 applications of LLLT had beneficial effects on the mice, with 3 being better than 1, but 14 applications had no beneficial effect. We now report immunofluorescence studies in mouse brain sections that offer some explanation for this intriguing finding. Mice were injected with BrdU for 1 week before sacrifice (a marker for proliferating cells) and antibodies to double cortin (DCX-1,a marker of migrating neurons), Tuj-1 ( a marker of neuroprogenitor cells), BDNF (brain derived neurotrophic factor) and synapsin-1 ( a marker for newly formed synaptic connections between existing neurons). We found increased BrdU incorporation indicating proliferating cells in the dentate gyrus of the hippocampus, the subventricular layer of the lateral ventricle, as well as the brain tissue surrounding the cortical lesion. Interestingly these cells were more abundant at 7 days than at 28 days post TBI. Co-labeling of BrdU with Neu-N was performed indicating that the proliferating cells were in fact neuronal in nature. Mice with 3 laser treatments had much more BrdU incorporation than mice with 14. Upregulation of BDNF was seen at 7 days, and increased expression of DCX-1 and Tuj-1 was seen at 28 days in the lesion region, indication that neuroprogenitor cells may have migrated there from sites of neurogenesis. Increased syapsin-1 was seen in the cortex at 28 days indicating that neural plasticity may be stimulated by LLLT. Taken together these data suggest that transcranial LLLT may have applications beyond TBI in areas such as neurodegenerative disease and psychiatric disorders.
Asheesh Gupta - One of the best experts on this subject based on the ideXlab platform.
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antimicrobial blue Light Therapy for multidrug resistant acinetobacter baumannii infection in a mouse burn model implications for prophylaxis and treatment of combat related wound infections
The Journal of Infectious Diseases, 2014Co-Authors: Yingying Huang, Asheesh Gupta, Michael R Hamblin, Clinton K. Murray, Yunsong Zhang, David G Baer, Mark S Vrahas, Margaret E SherwoodAbstract:In this study, we investigated the utility of antimicrobial blue Light Therapy for multidrug-resistant Acinetobacter baumannii infection in a mouse burn model. A bioluminescent clinical isolate of multidrug-resistant A. baumannii was obtained. The susceptibility of A. baumannii to blue Light (415 nm)–inactivation was compared in vitro to that of human keratinocytes. Repeated cycles of sublethal inactivation of bacterial by blue Light were performed to investigate the potential resistance development of A. baumannii to blue Light. A mouse model of third degree burn infected with A. baumannii was developed. A single exposure of blue Light was initiated 30 minutes after bacterial inoculation to inactivate A. baumannii in mouse burns. It was found that the multidrug-resistant A. baumannii strain was significantly more susceptible than keratinocytes to blue Light inactivation. Transmission electron microscopy revealed blue Light–induced ultrastructural damage in A. baumannii cells. Fluorescence spectroscopy suggested that endogenous porphyrins exist in A. baumannii cells. Blue Light at an exposure of 55.8 J/cm2 significantly reduced the bacterial burden in mouse burns. No resistance development to blue Light inactivation was observed in A. baumannii after 10 cycles of sublethal inactivation of bacteria. No significant DNA damage was detected in mouse skin by means of a skin TUNEL assay after a blue Light exposure of 195 J/cm2.
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effect of red and near infrared wavelengths on low level laser Light Therapy induced healing of partial thickness dermal abrasion in mice
Lasers in Medical Science, 2014Co-Authors: Asheesh Gupta, Michael R HamblinAbstract:Low-level laser (Light) Therapy (LLLT) promotes wound healing, reduces pain and inflammation, and prevents tissue death. Studies have explored the effects of various radiant exposures on the effect of LLLT; however, studies of wavelength dependency in in vivo models are less common. In the present study, the healing effects of LLLT mediated by different wavelengths of Light in the red and near-infrared (NIR) wavelength regions (635, 730, 810, and 980 nm) delivered at constant fluence (4 J/cm2) and fluence rate (10 mW/cm2) were evaluated in a mouse model of partial-thickness dermal abrasion. Wavelengths of 635 and 810 nm were found to be effective in promoting the healing of dermal abrasions. However, treatment using 730- and 980-nm wavelengths showed no sign of stimulated healing. Healing was maximally augmented in mice treated with an 810-nm wavelength, as evidenced by significant wound area reduction (p < 0.05), enhanced collagen accumulation, and complete re-epithelialization as compared to other wavelengths and non-illuminated controls. Significant acceleration of re-epithelialization and cellular proliferation revealed by immunofluorescence staining for cytokeratin-14 and proliferating cell nuclear antigen (p < 0.05) was evident in the 810-nm wavelength compared with other groups. Photobiomodulation mediated by red (635 nm) and NIR (810 nm) Light suggests that the biological response of the wound tissue depends on the wavelength employed. The effectiveness of 810-nm wavelength agrees with previous publications and, together with the partial effectiveness of 635 nm and the ineffectiveness of 730 and 980 nm wavelengths, can be explained by the absorption spectrum of cytochrome c oxidase, the candidate mitochondrial chromophore in LLLT.
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low level laser Light Therapy lllt in skin stimulating healing restoring
Seminars in Cutaneous Medicine and Surgery, 2013Co-Authors: Pinar Avci, Asheesh Gupta, Daniela Vecchio, Magesh Sadasivam, Michael R HamblinAbstract:Low-level laser (Light) Therapy (LLLT) is a fast-growing technology used to treat a multitude of conditions that require stimulation of healing, relief of pain and inflammation, and restoration of function. Although the skin is the organ that is naturally exposed to Light more than any other organ, it still responds well to red and near-infrared wavelengths. The photons are absorbed by mitochondrial chromophores in skin cells. Consequently electron transport, adenosine triphosphate (ATP) nitric oxide release, blood flow, reactive oxygen species increase and diverse signaling pathways get activated. Stem cells can be activated allowing increased tissue repair and healing. In dermatology, LLLT has beneficial effects on wrinkles, acne scars, hypertrophic scars, and healing of burns. LLLT can reduce UV damage both as a treatment and as a prophylaxis. In pigmentary disorders such as vitiligo, LLLT can increase pigmentation by stimulating melanocyte proliferation and reduce depigmentation by inhibiting autoimmunity. Inflammatory diseases such as psoriasis and acne can also benefit. The non-invasive nature and almost complete absence of side-effects encourages further testing in dermatology.
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transcranial low level laser Light Therapy for traumatic brain injury
Journal of Biophotonics, 2012Co-Authors: Yingying Huang, Asheesh Gupta, Michael R Hamblin, Daniela Vecchio, Vida Bil J De Arce, Shihfong Huang, Weijun XuanAbstract:We review the use of transcranial low-level laser (Light) Therapy (LLLT) as a possible treatment for traumatic-brain injury (TBI). The basic mechanisms of LLLT at the cellular and molecular level and its effects on the brain are outlined. Many interacting processes may contribute to the beneficial effects in TBI including neuroprotection, reduction of inflammation and stimulation of neurogenesis. Animal studies and clinical trials of transcranial-LLLT for ischemic stroke are summarized. Several laboratories have shown that LLLT is effective in increasing neurological performance and memory and learning in mouse models of TBI. There have been case report papers that show beneficial effects of transcranial-LLLT in a total of three patients with chronic TBI. Our laboratory has conducted three studies on LLLT and TBI in mice. One looked at pulsed-vs-continuous wave laser-irradiation and found 10 Hz to be superior. The second looked at four different laser-wavelengths (660, 730, 810, and 980 nm); only 660 and 810 nm were effective. The last looked at different treatment repetition regimens (1, 3 and 14-daily laser-treatments).
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transcranial low level laser Light Therapy for traumatic brain injury
Journal of Biophotonics, 2012Co-Authors: Yingying Huang, Asheesh Gupta, Daniela Vecchio, Vida Bil J De Arce, Shihfong Huang, Weijun Xuan, Michael R HamblinAbstract:We review the use of transcranial low-level laser (Light) Therapy (LLLT) as a possible treatment for traumatic-brain injury (TBI). The basic mechanisms of LLLT at the cellular and molecular level and its effects on the brain are outlined. Many interacting processes may contribute to the beneficial effects in TBI including neuroprotection, reduction of inflammation and stimulation of neurogenesis. Animal studies and clinical trials of transcranial-LLLT for ischemic stroke are summarized. Several laboratories have shown that LLLT is effective in increasing neurological performance and memory and learning in mouse models of TBI. There have been case report papers that show beneficial effects of transcranial-LLLT in a total of three patients with chronic TBI. Our laboratory has conducted three studies on LLLT and TBI in mice. One looked at pulsed-vs-continuous wave laser-irradiation and found 10 Hz to be superior. The second looked at four different laser-wavelengths (660, 730, 810, and 980 nm); only 660 and 810 nm were effective. The last looked at different treatment repetition regimens (1, 3 and 14-daily laser-treatments). (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Shihfong Huang - One of the best experts on this subject based on the ideXlab platform.
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transcranial low level laser Light Therapy for traumatic brain injury
Journal of Biophotonics, 2012Co-Authors: Yingying Huang, Asheesh Gupta, Michael R Hamblin, Daniela Vecchio, Vida Bil J De Arce, Shihfong Huang, Weijun XuanAbstract:We review the use of transcranial low-level laser (Light) Therapy (LLLT) as a possible treatment for traumatic-brain injury (TBI). The basic mechanisms of LLLT at the cellular and molecular level and its effects on the brain are outlined. Many interacting processes may contribute to the beneficial effects in TBI including neuroprotection, reduction of inflammation and stimulation of neurogenesis. Animal studies and clinical trials of transcranial-LLLT for ischemic stroke are summarized. Several laboratories have shown that LLLT is effective in increasing neurological performance and memory and learning in mouse models of TBI. There have been case report papers that show beneficial effects of transcranial-LLLT in a total of three patients with chronic TBI. Our laboratory has conducted three studies on LLLT and TBI in mice. One looked at pulsed-vs-continuous wave laser-irradiation and found 10 Hz to be superior. The second looked at four different laser-wavelengths (660, 730, 810, and 980 nm); only 660 and 810 nm were effective. The last looked at different treatment repetition regimens (1, 3 and 14-daily laser-treatments).
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transcranial low level laser Light Therapy for traumatic brain injury
Journal of Biophotonics, 2012Co-Authors: Yingying Huang, Asheesh Gupta, Daniela Vecchio, Vida Bil J De Arce, Shihfong Huang, Weijun Xuan, Michael R HamblinAbstract:We review the use of transcranial low-level laser (Light) Therapy (LLLT) as a possible treatment for traumatic-brain injury (TBI). The basic mechanisms of LLLT at the cellular and molecular level and its effects on the brain are outlined. Many interacting processes may contribute to the beneficial effects in TBI including neuroprotection, reduction of inflammation and stimulation of neurogenesis. Animal studies and clinical trials of transcranial-LLLT for ischemic stroke are summarized. Several laboratories have shown that LLLT is effective in increasing neurological performance and memory and learning in mouse models of TBI. There have been case report papers that show beneficial effects of transcranial-LLLT in a total of three patients with chronic TBI. Our laboratory has conducted three studies on LLLT and TBI in mice. One looked at pulsed-vs-continuous wave laser-irradiation and found 10 Hz to be superior. The second looked at four different laser-wavelengths (660, 730, 810, and 980 nm); only 660 and 810 nm were effective. The last looked at different treatment repetition regimens (1, 3 and 14-daily laser-treatments). (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Michael W Berns - One of the best experts on this subject based on the ideXlab platform.
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combination of low level Light Therapy and nitrosyl cobinamide accelerates wound healing
Journal of Biomedical Optics, 2015Co-Authors: Ryan Spitler, Hsiang Ho, Frederique Norpetlian, Xiangduo Kong, Jingjing Jiang, Kyoko Yokomori, Bogi Andersen, R Gerry M D Boss, Michael W BernsAbstract:Low level Light Therapy (LLLT) has numerous therapeutic benefits, including improving wound healing, but the precise mechanisms involved are not well established; in particular, the underlying role of cytochrome C oxidase (C-ox) as the primary photoacceptor and the associated biochemical mechanisms still require further investigation. We previously showed the nitric oxide (NO) donating drug nitrosyl-cobinamide (NO-Cbi) enhances wound healing through a cGMP/cGMP-dependent protein kinase/ERK1/2 mechanism. Here, we show that the combination of LLLT and NO-Cbi markedly improves wound healing compared to either treatment alone. LLLT-enhanced wound healing proceeded through an electron transport chain-C-ox-dependent mechanism with a reduction of reactive oxygen species and increased adenosine triphosphate production. C-ox was validated as the primary photoacceptor by three observations: increased oxygen consumption, reduced wound healing in the presence of sodium azide, and disassociation of cyanide, a known C-ox ligand, following LLLT. We conclude that LLLT and NO-Cbi accelerate wound healing through two independent mechanisms, the electron transport chain-C-ox pathway and cGMP signaling, respectively, with both resulting in ERK1/2 activation.
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comparison of laser and diode sources for acceleration of in vitro wound healing by low level Light Therapy
Journal of Biomedical Optics, 2014Co-Authors: Ryan Spitler, Michael W BernsAbstract:Low-level Light Therapy has been shown to improve in vitro wound healing. However, well-defined parameters of different Light sources for this Therapy are lacking. The goal of this study was (1) to determine if the wavelengths tested are effective for in vitro wound healing and (2) to compare a laser and a Light-emitting diode (LED) source at similar wavelengths. We show four wavelengths, delivered by either a laser or LED array, improved in vitro wound healing in A549, U2OS, and PtK2 cells. Improved wound healing occurred through increased cell migration demonstrated through scratch wound and transwell assays. Cell proliferation was tested by the (3-(4,5-dimethylthiazol-2-yl)-5-(3-car-boxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) (MTS) assay and was found generally not to be involved in the wound healing process. The laser and LED sources were found to be comparable when equal doses of Light were applied. The biological response measured was similar in most cases. We conclude that the laser at 652 (5.57 mW∕cm 2 , 10.02 J∕cm 2 ) and 806 nm (1.30 mW∕cm 2 , 2.334 J∕cm 2 ) (full bandwidth 5 nm), and LED at 637 (5.57 mW∕cm 2 , 10.02 J∕cm 2 ) and 901 nm (1.30 mW∕cm 2 , 2.334 J∕cm 2 ) (full bandwidth 17 and 69 nm respectively) induce comparable levels of cell migration and wound closure. © 2014 Society of Photo-Optical Instrumentation Engineers (SPIE) (DOI: 10.1117/1.JBO.19.3.038001)