50 Years Of Research. 50 Years Of Discovery.
The efficacy of PhotoBioModulation therapy has been well documented through thousands of studies. Summaries of a few studies can be found here. Talk to us about studies more specific to your areas of interest. There are now over 10,000* studies available.
Source: PBM Foundation
What is today called PhotoBioModulation (or PBM Red Light Therapy) was initially referred to as Low Level Light Therapy (LLLT) or Laser Therapy (due to early Laser light sources). Today, PhotoBioModulation is often referred to as PBM Red Light Therapy, or simply Red Light Therapy –– whether using Lasers as its light source, more modern LED's or next generation HyperPlasma, it's all PhotoBioModulation.
Study Focus
Light Therapy And The Brain
★ Light Therapy Is Safe And Effective For Treatment of TBI
Study shows PBM may benefit patients with moderate traumatic brain injury
★ Potentially Effective Treatment for a Range of Clinical Signs & Symptoms of PD
Improvements were maintained for as long as treatment continued
★ Complete & Fast Recovery from Idiopathic Facial Paralysis
Photobiomodulation is a promising Bell's Palsy treatment option
Light Therapy And Pain
★ An Effective Treatment For Chronic Knee Pain Caused By Knee Osteoarthritis
After end of the treatment regimen a significant improvement was observed .
★ Studies Confirm Positive Effects On Proinflammatory Biomarkers
Studies collected have excellent quality in terms of methodology .
★ Data suggest PBM could be tested in Human patients with Chronic Peripheral Pain
It would be clinically feasible to deliver PBM to the back or head of patients who are about to undergo a painful procedure .
Light Therapy And Wound Healing
★ Wound Healing in Post Chemo And Radiation Cancer Patients
Could enhance patients' quality of life, adherence to the prescribed cancer therapy, and treatment outcomes while reducing the cost of cancer care
★ Accelerated Burn Wound Healing with Photobiomodulation
Significant reduction in scarring and patient discomfort | fewer treatment delays-disruptions
★ PhotoBioModulation in Skin: stimulating, healing, restoring
Treats conditions that require stimulation of healing, relief of pain and inflammation, and restoration of function
RX Specific Research
RX Specific Studies
RX Specific Studies
↓ Contact Us For Copies Of These Studies
1. The RX1 and Its Effect on PRP
★ Growth Factor Release Reached 28 days (versus 10)
Sustained release of growth factors from photoactivated platelet plasma
2. The RX1 & Bone Fracture Treatment
★ Induced Formation of Bone Tissue
Polychromatic light-induced osteogenic activity in 2D and 3D cultures
3. The RX1 and Wounds
★ Enhanced Skin Flap Survival
PhotoBioModulation with polychromatic light increases zone 4 survival of transverse rectus abdominis musculocutaneous flap
4. The RX1 and Eyes
★ Effective and Safe for Corneal Tissue Regeneration
Investigation of healing strategies in a rat corneal opacity model with polychromatic light and stem cells injection
PhotoBioModulation | Research Abstracts
Pain Management
Please note: PhotoBioModulation (PBM) was initially referred to as Low Level Light Therapy (LLLT for short). As the modality has evolved, researchers have assigned many different descriptors –– often relating the process to its original light source (Lasers). Rest assured that whether any individual study used old style Lasers or more modern LED's or Hyper Plasma light sources, these are all examples of PhotoBioModulation at work.
Low Level Laser Therapy for chronic knee joint pain patients
Low Level Laser Therapy for chronic knee joint pain patients
Takashi Nakamura 1, Satoru Ebihara 2, Ikuko Ohkuni 2, Hideaki Izukura 2, Takashi Harada 2, Nobuyuki Ushigome 2, Toshio Ohshiro 3,
Yoshiro Musha 4, Hiroshi Takahashi 1, Kazuaki Tsuchiya 1, Ayako Kubota
Background and aims: Chronic knee joint pain is one of the most frequent complaints which is seen in the outpatient clinic in our medical institute. In previous studies we have reported the benefits of low level laser therapy (LLLT) for chronic pain in the shoulder joints, elbow, hand, finger and the lower back. The present study is a report on the effects of LLLT for chronic knee joint pain.
Materials and methods: Over the past 5 years, 35 subjects visited the outpatient clinic with complaints of chronic knee joint pain
caused by the knee osteoarthritis-induced degenerative meniscal tear. They received low level laser therapy.
A 1000 mW semiconductor laser device was used to deliver 20.1 J/cm(2) per point in continuous wave at
830nm, and four points were irradiated per session (1 treatment) twice a week for 4 weeks.
Results: A visual analogue scale (VAS) was used to determine the effects of LLLT for the chronic pain and after the end of the treatment
regimen a significant improvement was observed (p<0.001). After treatment, no significant differences were observed in the
knee joint range of motion. Discussions with the patients revealed that it was important for them to learn how to avoid postures that would cause them knee pain in everyday life in order to have continuous benefits from the treatment.
Conclusion: The present study demonstrated that 830 nm LLLT was an effective form of treatment for chronic knee pain caused by knee osteoarthritis. Patients were advised to undertake training involving gentle flexion and extension of the knee.
Efficacy of low power laser therapy and exercise on pain and functions in chronic low back pain.
Efficacy of low power laser therapy and exercise on pain and functions in chronic low back pain.
Gur A, Karakoc M, Cevik R, Nas K, Sarac AJ, Karakoc
BACKGROUND AND OBJECTIVES: The aim of this study was to determine whether low power laser therapy (Gallium-Arsenide) is useful or not for the therapy of chronic low back pain (LBP).
STUDY DESIGN/MATERIALS AND METHODS: This study included 75 patients (laser + exercise-25, laser alone-25, and exercise alone-25) with LBP.
Visual analogue scale (VAS), Schober test, flexion and lateral flexion measures, Roland Disability Questionnaire (RDQ) and Modified Oswestry Disability Questionnaire (MODQ) were used in the clinical and functional evaluations pre and post therapeutically. A physician, who was not aware of the therapy undertaken, evaluated the patients.
RESULTS: Significant improvements were noted in all groups with respect to all outcome parameters, except lateral flexion (P < 0.05).
CONCLUSIONS: Low power laser therapy seemed to be an effective method in reducing pain and functional disability in the therapy of chronic LBP.
Lasers Surg Med 2003 32(3) 233-8 7
Does addition of low-level laser therapy (LLLT) in conservative care of knee arthritis successfully postpone the need for joint replacement?
Does addition of low-level laser therapy (LLLT) in conservative care of knee arthritis successfully postpone the need for joint replacement?
Basavaraj M Kajagar 1, Ashok S Godhi, Archit Pandit, S Khatri
The current study evaluates whether the addition of low-level laser therapy into standard conventional physical therapy in elderly with bilateral symptomatic tricompartmental knee arthritis can successfully postpone the need for joint replacement surgery.
A prospective randomized cohort study of 100 consecutive unselected elderly patients with bilateral symptomatic knee arthritis with each knee randomized to receive either treatment protocol A consisting of conventional physical therapy or protocol B which is the same as protocol A with added low-level laser therapy.
The mean follow-up was 6 years. Treatment failure was defined as breakthrough pain which necessitated joint replacement surgery.
Results: After a follow-up of 6 years, patients clearly benefited from treatment with protocol B as only one knee needed joint replacement surgery,
while nine patients treated with protocol A needed surgery (p < 0.05).
Conclusions: We conclude low-level laser therapy should be incorporated into standard conservative treatment protocol for
symptomatic knee arthritis.
Mechanisms and applications of the anti-inflammatory
effects of photobiomodulation
Mechanisms and applications of the anti-inflammatory effects of photobiomodulation
Michael R Hamblin
Background: Photobiomodulation (PBM) also known as low-level level laser therapy is the use of red and near-infrared light to stimulate healing, relieve pain, and reduce inflammation.
The primary chromophores have been identified as cytochrome c oxidase in mitochondria, and calcium ion channels (possibly mediated by light absorption by opsins). Secondary effects of photon absorption include increases in ATP, a brief burst of reactive oxygen species, an increase in
nitric oxide, and modulation of calcium levels. Tertiary effects include activation of a wide range of transcription factors leading to improved cell survival, increased proliferation and migration, and new protein synthesis.
Summary Results: There is a pronounced biphasic dose response whereby low levels of light have stimulating effects, while high levels of light have inhibitory effects. It has been found that PBM can produce ROS in normal cells, but when used in oxidatively stressed cells or in animal models of disease, ROS levels are lowered. PBM is able to up-regulate anti-oxidant defenses and reduce oxidative stress.
It was shown that PBM can activate NF-kB in normal quiescent cells, however in activated inflammatory cells, inflammatory markers were decreased.
One of the most reproducible effects of PBM is an overall reduction in inflammation, which is particularly important for disorders of the joints, traumatic injuries, lung disorders, and in the brain.
PBM has been shown to reduce markers of M1 phenotype in activated macrophages. Many reports have shown reductions in reactive nitrogen species and prostaglandins in various
animal models.
Conclusion: PBM can reduce inflammation in the brain, abdominal fat, wounds, lungs, spinal cord.
Keywords: animal studies; chromophores; clinical trials; inflammation; low-level laser therapy;
photobiomodulation.
PhotoBioModulation | Research Abstracts
Wound Healing
Please note: PhotoBioModulation (PBM) was initially referred to as Low Level Light Therapy (LLLT for short). As the modality has evolved, researchers have assigned many different descriptors –– often relating the process to its original light source (Lasers). Rest assured that whether any individual study used old style Lasers or more modern LED's or Hyper Plasma light sources, these are all examples of PhotoBioModulation at work.
Phototherapy improves healing of chronic venous ulcers
Phototherapy improves healing of chronic venous ulcers
Kelly Steinkopf Caetano 1, Marco Andrey Cipriani Frade, Débora Garbin Minatel, Luisiane Avila, Santana, Chukuka S Enwemeka
Objective: We tested the hypothesis that LED phototherapy with combined 660-nm and 890-nm light will promote healing of venous ulcers that failed to respond to other forms of treatment.
Background data: A variety of dressings, growth factors, and adjunct therapies are used to treat venous ulcers, but none seems to yield satisfactory results.
Materials and methods: We used a randomized placebo-controlled double-blind study to compare a total of 20 patients divided with 32 chronic ulcers into three groups.
In group 1 the ulcers were cleaned, dressed with 1% silver sulfadiazine (SDZ) cream, and treated with placebo phototherapy (<.03 J/cm(-3)) using a Dynatron Solaris 705 phototherapy research device.
In group 2 the ulcers were treated similarly but received real phototherapy (3 J/cm(-2)) instead of placebo.
In group 3 (controls), the ulcers were simply cleaned and dressed with SDZ without phototherapy.
The ulcers were evaluated with digital photography and computer image analysis over 90 d or until full healing was attained.
Results: Ulcers treated with phototherapy healed significantly faster than controls when compared at day 30 (p +/- 0.01), day 60 (p +/- 0.05), and day 90 (p +/- 0.001), and similarly
healed faster than the placebo-treated ulcers at days 30 and 90 (p +/- 0.01), but not at day 60.
The beneficial effect of phototherapy was more pronounced when the confounding effect of small sized ulcers was removed from the analysis. Medium- and large-sized ulcers healed significantly faster with treatment (>or=40% rate of healing per month) than placebo or control ulcers (p +/- 0.05).
Conclusion: Phototherapy promotes healing of chronic venous ulcers, particularly large recalcitrant ulcers that do not respond to conventional treatment.
Auto-Administered Photobiomodulation on Diabetic Leg Ulcers Treatment: A New Way to Manage It?
Auto-Administered Photobiomodulation on Diabetic Leg Ulcers Treatment: A New Way to Manage It?
Elisabetta Merigo 1, Lixin Tan 2, Zengyi Zhao 2 3, Jean-Paul Rocca 1 3, Carlo Fornaini 1 4
Background: Peripheral arterial disease is a dramatic consequence of an uncontrolled diabetic condition causing an increase of morbidity and mortality and its treatment is currently medical or surgical, finally requiring, in the 7-20% of cases, major or minor amputation.
Photobiomodulation therapy (PBM) is a laser treatment used in medicine, thanks to its ability to stimulate the wound healing, the acceleration of inflammatory process, and the modulation of pain. Recently, the self-administration of the treatment has been suggested for different purposes in medicine and dentistry with a great number of advantages and no side effects.
Methods: A 84-year-old woman affected by diabetes type 2 and positive for diabetes complications had diagnosis for an ulcerative lesion of 1 cm diameter on her right leg and started
a treatment of the lesion applying the B-Cure Laser Pro (Erika Carmel, Haifa, Israel) on her own with a fluence per minute of 3.2 J/cm2 for 2 sessions of 15 minutes by cutaneous application.
Results: After a week of treatment, the ulcer dried and crusted, finally providing complete healing after 30 days of treatment.
Conclusion: With this short case report, we think to add a further contribution by suggesting this kind of treatment for successful management of the leg ulcers in diabetic patients.
Copyright © 2020 Elisabetta Merigo et al.
Efficacy of low level laser therapy on wound healing in patients with chronic diabetic foot ulcers.
Efficacy of low level laser therapy on wound healing in patients with chronic diabetic foot ulcers-a randomised control trial
Basavaraj M Kajagar 1, Ashok S Godhi, Archit Pandit, S Khatri
Foot ulcers are serious complications of Diabetes Mellitus (DM) and are known to be resistant to conventional treatment. They may herald severe complications if not treated wisely. Electromagnetic radiations in the form of photons are delivered to the ulcers in laser form to stimulate healing. This study was conducted to evaluate the efficacy of Low Level Laser Therapy (LLLT) in diabetic ulcer healing dynamics. To determine mean percentage reduction of wound area in study and control groups.
Settings: KLES Dr. Prabhakar Kore Hospital and Medical Research Centre, Belgaum.
Study design: Randomized-Control Study.
Methods: A total of 68 patients with Type 2 DM having Meggitt-Wagner Grade I foot ulcers of at least more than 4 weeks duration, less than 6 Å~ 6 cm(2) with negative culture were studied. Patients were randomized into two groups of 34 each. Patients in study group received LLLT with conventional therapy and those in control group were treated with conventional therapy alone. Healing or percentage reduction in ulcer area over a period of 15 days after commencement of treatment was recorded.
Statistical analysis: Unpaired Student T Test and Mann Whitney U test. Mean age of the patients was 50.94 years in control group and 54.35 years in study group (p = 0.065). There was no significant difference between control and study group with respect to mean FBS and HbA1c
levels (p > 0.05), suggesting no biochemical differences between two groups.
Initial ulcer area was 2608.03 mm(2) in study group and 2747.17 mm(2) in control group (p = 0.361). Final ulcer area was 1564.79 mm(2) in study group and 2424.75 mm(2) in control group (p = 0.361). Percentage ulcer area reduction was 40.24 Å} 6.30 mm(2) in study group and 11.87 Å} 4.28 mm(2) in control group (p < 0.001, Z = 7.08).
Low Level Laser Therapy is beneficial as an adjunct to conventional therapy in the treatment of diabetic foot ulcers (DFU).
Keywords: Adjuvant therapies; Diabetic foot ulcers; Low Level Laser Therapy (LLLT); Wound healing.
Phototherapy promotes healing of chronic diabetic leg ulcers that failed to respond to other therapies
Phototherapy promotes healing of chronic diabetic leg ulcers that failed to respond to other therapies
Debora G Minatel, Marco Andrey C Frade, Suzelei C França, Chukuka S Enwemeka
Objective: We tested the hypothesis that combined 660 and 890 nm LED phototherapy will promote healing of diabetic ulcers that failed to respond to other forms of treatment.
Research design and methods: A double-blind randomized placebo controlled design was used to study 23 diabetic leg ulcers in two groups of 14 patients. Group one ulcers were cleaned, dressed with 1% silver sulfadiazine cream and treated with "placebo" phototherapy (<1.0 J cm(-2)) twice per week, using a Dynatron Solaris 705(R) device. Group two ulcers were treated similarly but received 3 J cm(-2) dose.
Results: At each of 15, 30, 45, 60, 75, and 90 days of healing, mean ulcer granulation and healing rates were significantly higher for group two than the "placebo" group (P < 0.02).
While "placebo" treated ulcers worsened during the initial 30 days, group two ulcers healed rapidly; achieving 56% more granulation and 79.2% faster healing by day 30, and maintaining similarly higher rates of granulation and healing over the "placebo" group all through. By day 90, 58.3% of group two ulcers had healed fully and 75% had achieved 90-100% healing. In contrast, only one "placebo" treated ulcer healed fully by day 90; no other ulcer attained > or =90% healing.
Conclusion: Combined 660 and 890 nm light promotes rapid granulation and healing of diabetic ulcers that failed to respond to other forms of treatment.
Copyright 2009 Wiley-Liss, Inc.
PhotoBioModulation | Research Abstracts
Skin
Please note: PhotoBioModulation (PBM) was initially referred to as Low Level Light Therapy (LLLT for short). As the modality has evolved, researchers have assigned many different descriptors –– often relating the process to its original light source (Lasers). Rest assured that whether any individual study used old style Lasers or more modern LED's or Hyper Plasma light sources, these are all examples of PhotoBioModulation at work.
A Controlled Trial to Determine the Efficacy of Red and Near-
Infrared Light Treatment in Patient Satisfaction, Reduction of Fine Lines, Wrinkles, Skin Roughness, and Intradermal Collagen Density Increase
A Controlled Trial to Determine the Efficacy of Red and Near-Infrared Light Treatment in Patient Satisfaction, Reduction of Fine
Lines, Wrinkles, Skin Roughness, and Intradermal Collagen Density Increase
Alexander Wunsch and Karsten Matuschka
Objective: The purpose of this study was to investigate the safety and efficacy of two novel light sources for large area and full body application, providing polychromatic, non-thermal photobiomodulation (PBM) for improving skin feeling and appearance.
Background data: For nonthermal photorejuvenation, laser and LED light sources have been demonstrated to be safe and effective. However, lasers and LEDs may offer some disadvantages because of dot-shaped
(punctiform) emission characteristics and their narrow spectral bandwidths. Because the action spectra
for tissue regeneration and repair consist of more than one wavelength, we investigated if it is
favorable to apply a polychromatic spectrum covering a broader spectral region for skin rejuvenation
and repair. Materials and methods: A total of 136 volunteers participated in this prospective,
randomized, and controlled study. Of these volunteers, 113 subjects randomly assigned into four
treatment groups were treated twice a week with either 611–650 or 570–850 nm polychromatic light
(normalized to ∼9 J/cm in the range of 611–650 nm) and were compared with controls (n=23).
Irradiances and treatment durations varied in all treatment groups. The data collected at baseline and
after 30 sessions included blinded evaluations of clinical photography, ultrasonographic collagen
density measurements, computerized digital profilometry, and an assessment of patient satisfaction.
Results: The treated subjects experienced significantly improved skin complexion and skin feeling,
profilometrically assessed skin roughness, and ultrasonographically measured collagen density. The
blinded clinical evaluation of photographs confirmed significant improvement in the intervention
groups compared with the control.
Conclusions: Broadband polychromatic PBM showed no advantage over the red-light-only spectrum. However, both novel light sources that have not been previously used for PBM have demonstrated efficacy and safety for skin rejuvenation and intradermal collagen increase when compared with controls.
Low-level laser (light) therapy (LLLT) in skin: stimulating,
healing, restoring
Low-level laser (light) therapy (LLLT) in skin: stimulating, healing, restoring
Pinar Avci, MD, Asheesh Gupta, PhD, Magesh Sadasivam, MTech, Daniela Vecchio, PhD,
Zeev Pam, MD, Nadav Pam, MD, and Michael R Hamblin, PhD
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 hasbeneficial 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 noninvasive
nature and almost complete absence of side-effects encourages further testing in dermatology.
Keywords: Acne, Dermatology, Herpes, Laser, LLLT, Low level laser therapy, Phototherapy, Skin
disease, Skin Rejuvenation, Pigmentation, Vitiligo
Efficacy of phototherapy to treat facial ageing when using a red versus an amber LED
A protocol for a randomised contolled trial
Efficacy of phototherapy to treat facial ageing when using a red versus an amber LED: a protocol for a randomised controlled trial
Lidiane Rocha Mota, Lara Jansiski Motta, Ivone da Silva Duarte, Anna Carolina Ratto Tempestini Horliana,
Daniela de Fatima Teixeira da Silva, and Christiane Pavani
Introduction
The skin undergoes morphological and physiological changes with the advancing age of an individual. These changes may be caused by intrinsic and extrinsic factors that contribute to cellular ageing and consequent skin ageing. The term photoageing is used to characterise the ageing of the skin caused by solar radiation.
Clinically, the skin becomes more flaccid, thicker and hyperpigmented, while there is an early appearance of wrinkles and other skin changes, such as skin cancer. Nowadays, there are numerous treatments for ageing skin, and one of them is with the use of phototherapy, which uses lightemitting diodes (LEDs). The objective of this study will be to evaluate the percentages of reduction in the volume of periocular wrinkles when treated with red and amber LEDs.
Methods and analysis
All of the participants will receive photobiomodulation to treat their periocular wrinkles. They will be using red and amber LEDs, with one colour being used on each hemiface. The facial side to be treated with each colour will be randomised. After an interval of 180 days, the participants will receive a cross-treatment. The primary variable of the study is the volume of periocular wrinkles (crow’s feet), which will be measured by a VisioFace equipment.
The secondary variables are elasticity (measured by Cutometer) and hydration (measured by Corneometer). Quality of life and self-assessment of the participants will be measured using the adapted Melasma Quality of Life scale - Brazilian Portuguese adaption (MelasQoL-BP) and Skindex-29 questionnaires. All of the variables will be measured before and after a group of 10 sessions.
Ethics and dissemination
This protocol was approved by the Research Ethics Committee of the Nove de Julho University (acceptance number: 2.550.732). This trial has been registered in the Registro Brasileiro de Ensaios Cl nicos (Brazilian Clinical Trials Registry) (REBEC number: RBR-6YFCBM). This study is not recruiting yet.
Trial registration number: RBR6YFCBM; Pre-results.
Keywords: skin aging, wrinkles, phototherapy, photobiomodulation, photodermatology
PhotoBioModulation | Research Abstracts
Sports Recovery
Please note: PhotoBioModulation (PBM) was initially referred to as Low Level Light Therapy (LLLT for short). As the modality has evolved, researchers have assigned many different descriptors –– often relating the process to its original light source (Lasers). Rest assured that whether any individual study used old style Lasers or more modern LED's or Hyper Plasma light sources, these are all examples of PhotoBioModulation at work.
When is the best moment to apply photobiomodulation
therapy (PBMT) when associated to a treadmill endurance training program?
A randomized, triple-blinded, placebo controlled clinical trial
When is the best moment to apply photobiomodulation therapy (PBMT) when associated to a treadmill endurance-training program?
A randomized, triple-blinded, placebo controlled clinical trial
Eduardo Foschini Miranda, Shaiane Silva Tomazoni Paulo Roberto Vicente de Paiva, Henrique Dantas Pinto, Denis Smith, Larissa Aline Santos, Paulo de Tarso Camillo de Carvalho, Ernesto Cesar Pinto Leal-Junior
Photobiomodulation therapy (PBMT) employing low-level laser therapy (LLLT) and/or light emitting diode therapy (LEDT) has emerged as an electrophysical intervention that could be associated with aerobic training to enhance beneficial effects of aerobic exercise. However, the best moment to perform irradiation with PBMT in aerobic training has not been elucidated.
The aim of this study was to assess the effects of PBMT applied before and/or after each training session and to evaluate outcomes of the
endurance-training program associated with PBMT.
Seventy-seven healthy volunteers completed the treadmill-training protocol performed for 12 weeks, with 3 sessions per week. PBMT was performed before and/or after each training session (17 sites on each lower limb, using a cluster of 12 diodes: 4 905 nm super-pulsed laser diodes, 4 875 nm infrared LEDs, and 4 640 nm red LEDs, dose of 30 J per site).
Volunteers were randomized in four groups according to the treatment they would receive before and after each training session: PBMT before + PBMT after, PBMT before + placebo after, placebo before + PBMT after, and placebo before + placebo after. Assessments were performed before the start of the protocol and after 4, 8, and 12 weeks of training.
Primary outcome was time until exhaustion; secondary outcome measures were oxygen uptake and body fat. PBMT applied before and after aerobic exercise training sessions (PBMT before + PBMT after group) significantly increased (p < 0.05) the percentage of change of time until exhaustion and oxygen uptake compared to the group treated with placebo before and after aerobic exercise training sessions (placebo before + placebo after group) at 4th, 8th, and 12th week. PBMT applied before and after aerobic exercise training sessions (PBMT before + PBMT after group) also significantly improved (p < 0.05) the percentage of change of body fat compared to the group treated with placebo before and after aerobic exercise training sessions (placebo before + placebo after group) at 8th and 12th week.
PBMT applied before and after sessions of aerobic training during 12 weeks can increase the time-to-exhaustion and oxygen uptake and also
decrease the body fat in healthy volunteers when compared to placebo irradiation before and after exercise sessions.
Our outcomes show that PBMT applied before and after endurance-training exercise sessions lead to improvement of endurance three times faster than exercise only.
Is photobiomodulation therapy better than cryotherapy
in muscle recovery after a high-intensity exercise?
A randomized, double-blind, placebo controlled clinical trial
Is photobiomodulation therapy better than cryotherapy in musclerecovery after a high-intensity exercise?
Thiago De Marchi, Vinicius Mazzochi Schmitt, Guilherme Pinheiro Machado, Juliane Souza de Sene, Camila Dallavechia de Col, Olga Tairova, Mirian Salvador, Ernesto Cesar Pinto Leal-Junior
This study aimed to determine the effectiveness of photobiomodulation therapy (PBMT) and cryotherapy, in isolated and combined forms, as muscle recovery techniques after muscle fatigue-inducing protocol.
Forty volunteers were randomly divided into five groups: a placebo group (PG); a PBMT group (PBMT); a cryotherapy group (CG); a cryotherapy-PBMT group (CPG); and a PBMT-cryotherapy group (PCG). All subjects performed four sessions at 24-h intervals, during which they submitted to isometric assessment (MVC) and blood collection in the pre-exercise period, and 5 and 60 min post-exercise, while the muscle fatigue induction protocol occurred after the preexercise collections. In the remaining sessions performed 24, 48, and 72 h later, only blood collections and MVCs were performed. A single treatment with PBMT and/or cryotherapy was applied after only 2 min of completing the post-5-min MVC test at the first session.
In the intragroup comparison, it was found that exercise led to a significant decrease (p < 0.05) in the production of MVC in all groups. Comparing the results of MVCs between groups, we observed significant increases in the MVC capacity of the PBMT, CPG, and PCG volunteers in comparison with both PG and CG (p < 0.05). We observed a significant decrease in the concentrations of the biochemical markers of oxidative damage (TBARS and PC) in all groups and muscle damage (creatine kinase-CK)
in the PBMT, PCG, and CPG compared with the PG (p < 0.01).
The clinical impact of these findings is clear because they demonstrate that the use of phototherapy is more effective than the use of cryotherapy for muscle recovery, additionally cryotherapy decreases PBMT efficacy.
Effects of low-level laser therapy and eccentric exercises
in the treatment of recreational athletes with chronic
achilles tendinopathy
Effects of low-level laser therapy and eccentric exercises in the treatment of recreational athletes with chronic achilles tendinopathy
Apostolos Stergioulas, Marianna Stergioula, Reidar Aarskog, Rodrigo A B Lopes-Martins, Jan
M Bjordal
Background: Eccentric exercises (EEs) are recommended for the treatment of Achilles tendinopathy, but the clinical effect from EE has a slow onset.
Hypothesis: The addition of low-level laser therapy (LLLT) to EE may cause more rapid clinical improvement.
Study design: Randomized controlled trial; Level of evidence, 1.
Methods: A total of 52 recreational athletes with chronic Achilles tendinopathy symptoms were randomized to groups receiving either EE + LLLT or EE + placebo LLLT over 8 weeks in a blinded manner. Low-level laser therapy (lambda = 820 nm) was administered in 12 sessions by irradiating 6 points along the Achilles tendon with a power density of 60 mW/cm(2) and a total dose of 5.4 J per session.
Results: The results of the intention-to-treat analysis for the primary outcome, pain intensity during physical activity on the 100-mm visual analog scale, were significantly lower in the LLLT group than in the placebo LLLT group, with 53.6 mm versus 71.5 mm (P = .0003) at 4 weeks, 37.3 mm versus 62.8 mm (P = .0002) at 8 weeks, and 33.0 mm versus 53.0 mm (P = .007) at 12 weeks after randomization. Secondary outcomes of morning stiffness, active dorsiflexion, palpation tenderness, and crepitation showed the same pattern in favor of the LLLT group.
Conclusion: Low-level laser therapy, with the parameters used in this study, accelerates clinical
recovery from chronic Achilles tendinopathy when added to an EE regimen. For the LLLT
group, the results at 4 weeks were similar to the placebo LLLT group results after 12 weeks.
Effectiveness of Photobiomodulation Therapy Versus
Cryotherapy for Skeletal Muscle Recovery: A Critically Appraised Topic
Effectiveness of Photobiomodulation Therapy Versus Cryotherapy for Skeletal Muscle Recovery: A Critically Appraised Topic
Stephan R Fisher, Justin H Rigby, Joni A Mettler, Kevin W McCurdy
Clinical Scenario: Cryotherapy is one of the most commonly used modalities for postexercise muscle recovery despite inconsistencies in the literature validating its effectiveness. With the need to find a more effective modality, photobiomodulation therapy (PBMT) has gained popularity because of recent research demonstrating its ability to accelerate the muscle recovery process.
Focused Clinical Question: Is PBMT more effective than cryotherapy at reducing recovery time and decreasing delayed onset muscle soreness after strenuous exercise?
Summary of Key Findings: Three moderate - to high-quality double-blinded, randomized, placebo-controlled trials and 2 low - to moderate-quality translational studies performed on rats were included in this critically appraised topic.
All 5 studies supported the use of PBMT over cryotherapy as a treatment for postexercise muscle recovery following exercise. PBMT was superior in reducing creatine kinase, inflammation markers, and blood lactate compared with cryotherapy, following strenuous/high intensity aerobic or strength muscular exercise.
PBMT was also shown to improve postexercise muscle performance and function more than cryotherapy.
Clinical Bottom Line: There is moderate evidence to suggest the use of PBMT over cryotherapy postexercise to enhance muscle recovery in trained and untrained athletes. Shorter recovery times and increased muscle performance can be seen 24 to 96 hours following PBMT application.
Strength of Recommendation: Based on consistent findings from all 5 studies, there is grade B evidence to support the use of PBMT over cryotherapy for more effective postexercise recovery of skeletal muscle performance.
What is the best moment to apply phototherapy
when associated to a strength training program?
A randomized, double-blind, placebo controlled trial
What is the best moment to apply phototherapy when associated to a strength training program?
Adriane Aver Vanin , Eduardo Foschini Miranda, Caroline Santos Monteiro Machado, Paulo Roberto Vicente de Paiva, Gianna M es Albuquerque-Pontes, Heliodora Leo Casalechi, Paulo de Tarso Camillo de Carvalho3, Ernesto Cesar Pinto Leal-Junior
The effects of phototherapy (or photobiomodulation therapy) with low-level laser therapy (LLLT) and/or light-emitting diodes (LEDs) on human performance improvement have been widely studied. Few studies have examined its effect on muscular training and no studies have explored the necessary moment of phototherapy irradiations (i.e., before and/or after training sessions).
The aim of this study was to determine the optimal moment to apply phototherapy irradiation when used in association with strength training.
Forty-eight male volunteers (age between 18 to 35 years old) completed all procedures in this study. Volunteers performed the strength training protocol where either a phototherapy and/or placebo before and/or after each training session was performed using cluster probes with four laser diodes of 905 nm, four LEDs of 875 nm, and four LEDs of 640 nm-manufactured by Multi Radiance Medical™. The training protocol duration was 12 weeks with assessments of peak torque reached in maximum voluntary contraction test (MVC), load in 1-repetition maximum test (1-RM) and thigh circumference (perimetry) at larger cross-sectional area (CSA) at baseline, 4 weeks, 8 weeks, and 12 weeks.
Volunteers from group treated with phototherapy before and placebo after training sessions showed significant (p < 0.05) changes in MVC and 1- RM tests for both exercises (leg extension and leg press) when compared to other groups.
With an apparent lack of side effects and safety due to no thermal damage to the tissue, we conclude that the application of phototherapy yields enhanced strength gains when it is applied before exercise. The application may have additional beneficial value in post-injury rehabilitation where strength improvements are needed.
PhotoBioModulation | Research Abstracts
Stem | Dentistry | Vision
Please note: PhotoBioModulation (PBM) was initially referred to as Low Level Light Therapy (LLLT for short). As the modality has evolved, researchers have assigned many different descriptors –– often relating the process to its original light source (Lasers). Rest assured that whether any individual study used old style Lasers or more modern LED's or Hyper Plasma light sources, these are all examples of PhotoBioModulation at work.
Effect of Photobiomodulation on Mesenchymal Stem Cells
Effect of photobiomodulation (PBM) on mesenchymal stem cells
Basavaraj M Kajagar 1, Ashok S Godhi, Archit Pandit, S Khatri
Objective: The purpose of this study was to review available literature about the effect of photobiomodulation (PBM) on mesenchymal stem cells (MSCs).
Background data: The effects of coherent and noncoherent light sources such as lowl evel lasers and light-emitting diodes (LEDs) on cells and tissues, known as PBM, form the basis of photomedicine. This treatment technique effects cell function, proliferation, and migration, and plays an important role in tissue regeneration. Stem cells have been found to be helpful elements in tissue regeneration, and the combination of stem cell therapy and laser therapy appears to positively affect treatment results.
Materials and methods: An electronic search in PubMed was conducted of publications from the previous 12 years. English language articles related to the subject were found using selected key words. The full texts of potentially suitable articles were assessed according to inclusion and exclusion criteria.
Results: After evaluation, 30 articles were deemed relevant according to the inclusioncriteria. The energy density of the laser was 0.7-9 J/cm2. The power used for visible light was 30-110 mW and that used for infrared light was 50-800 mW. Nearly all studies showed that low-level laser therapy had a positive effect on cell proliferation. Similar outcomes were found for LED; however, some studies suggest that the laser alone is not effective, and should be used as an adjunct tool.
Conclusions: PBM has positive effects on MSCs.
This review concluded that doses of 0.7-4 J/cm2and wavelengths of 600-700 nm are appropriate for light therapy. The results were dependent upon different parameters; therefore, optimization of parameters used in light therapy to obtain favorable results is required to provide more accurate comparison.
Beyond 2D: effects of photobiomodulation in 3D tissue-like systems
Beyond 2D: effects of photobiomodulation in 3D tissue-like systems
Polina Y Bikmulina, Nastasia V Kosheleva, Anastasia I Shpichka, Yuri M Efremov, Vladimir I Yusupov, Peter S Timashev, Yury A Rochev
Significance: Currently, various scaffolds with immobilized cells are widely used in tissue engineering and regenerative medicine. However, the physiological activity and cell viability in such constructs might be impaired due to a lack of oxygen and nutrients. Photobiomodulation (PBM) is a promising method of preconditioning cells to increase their metabolic activity and to activate proliferation or differentiation.
Aim: Investigation of the potential of PBM for stimulation of cell activities in hydrogels.
Approach: Mesenchymal stromal cells (MSCs) isolated from human gingival mucosa were encapsulated in modified fibrin hydrogels with different thicknesses and concentrations. Constructs with cells were subjected to a single-time exposure to red (630 nm) and near-infrared (IR) (840 nm) low-intensity irradiation. After 3 days of cultivation, the viability and physiological activity of the cells were analyzed using confocal microscopy and a set of classical tests for cytotoxicity.
Results: The cell viability in fibrin hydrogels depended both on the thickness of the hydrogels and the concentration of gel-forming proteins. The PBM was able to improve cell viability in hydrogels. The most pronounced effect was achieved with near-IR irradiation at the 840-nm wavelength.
Conclusions: PBM using near-IR light can be applied for stimulation of MSCs metabolism and proliferation in hydrogel-based constructs with thicknesses up to 3 mm.
Keywords: fibrin; hydrogel; mesenchymal stromal cells; photobiomodulation; regenerative medicine; tissue engineering.
Photobiomodulation Therapy Promotes
Expansion of Epithelial Colony Forming Units
Photobiomodulation Therapy Promotes Expansion of Epithelial Colony Forming Units
Imran Khan, Praveen R Arany
Objective: This preliminary study examines the effects of low-dose light therapy, also called Photobiomodulation (PBM) therapy, on epithelial colony forming units (eCFUs) in epithelial cells from skin and mucosa to assess their potential to contribute to tissue regeneration. Also, preliminary comparison of basic PBM parameters such as wavelengths, light sources, and dose were evaluated in promoting eCFUs.
Background data: Regenerative medicine is at the brink of exploiting the tremendous potential offered by advances in stem cell biology. The two distinct aspects for utilization of stem cells, either resident (endogenous) or transplanted (exogenous), rely on cells amenable to expansion and being directed toward mature, functional tissues. Despite major progress in fundamental understanding of stem cell pluripotency, there remain fundamental challenges in applying these insights into clinical practice.
Methods: PBM treatments with various devices, wavelengths, and doses were used on two epithelial cell lines and colony forming assays were performed.
Results: This study noted a dose-dependent effect of 810 nm laser on increasing eCFUs, either in terms of size or numbers. Comparisons of different wavelengths and light sources noted better efficacy of collimated and coherent lasers compared to LEDs and broad-band light.
Conclusions: PBM therapy promotes expansion of eCFUs that represent progenitors and stem cell populations capable of contributing to tissue repair and regeneration. Further exploration of the precise mechanisms would allow optimization of PBM clinical protocols to harness the regenerative potential of stem cells for wound healing and other clinical regenerative applications.
Photobiomodulation-Induced Differentiation of
Immortalized Adipose Stem Cells to Neuronal Cells
Photobiomodulation-Induced Differentiation of Immortalized Adipose Stem Cells to Neuronal Cells
Sajan George, Michael R Hamblin, Heidi Abrahamse
Background and objectives:
Transdermal differentiation of human adipose stem cells (ASCs) to other cell types is still a challenge in regenerative medicine. Studies using primary ASCs are also limited as they may undergo replicative senescence during repeated passages in vitro. However, ASCs immortalized (iASCs) with human telomerase enzyme expressing plasmid exhibits a uniform population suitable for differentiation in vitro. A right combination of biological and physical stimuli may induce transdermal differentiation of iASCs into neurons in vitro.
Study design/materials and methods: iASCs were differentiated to free-floating neural stem cell aggregates (neurospheres) using a combination of growth inducers. Cells in these spheres were induced to differentiate into neurons using low-intensity lasers by a process called photobiomodulation (PBM).
Results: Laser at the near infrared (NIR) wavelength 825 nm and fluences 5, 10, and 15 J/cm2 was capable of increasing the differentiation of neurospheres to neurons. Precisely, there was a statistically significant increase in the early neuronal marker at 5 J/cm2 and a much appreciable increase at 15 J/cm2 in correlation with the biphasic dose response of PBM. However, these differentiated cells failed to express late neuronal markers in vitro. Comparison of these differentiating iASCs with the primary ASCs revealed a sharp distinction between the metabolic processes of the primary ASCs, neurospheres, and newly differentiated neurons.
Conclusion: We found that PBM increased the yield of neurons and effected stem cell differentiation through modulation of cellular metabolism and redox status. Our study also identifies that iASCs are an excellent model for analysis of stem cell biology and for performing transdermal differentiation.
Significance: This study demonstrates that a combination of biological and physical inducers can advance the differentiation of adipose stem cells to neurons. We were able to establish the optimal energy for the neuronal differentiation of iASCs in vitro. Lasers Surg. Med.
© 2020 Wiley Periodicals LLC.
Keywords: adipose stem cells; differentiation; laser; metabolism; neurons; photobiomodulation
PhotoBioModulation | Research Abstracts
BRAIN
Please note: PhotoBioModulation (PBM) was initially referred to as Low Level Light Therapy (LLLT for short). As the modality has evolved, researchers have assigned many different descriptors –– often relating the process to its original light source (Lasers). Rest assured that whether any individual study used old style Lasers or more modern LED's or Hyper Plasma light sources, these are all examples of PhotoBioModulation at work.
MGH-led study shows light therapy is safe, modulates brain repair, and may benefit patients with moderate traumatic brain injury
Key Takeaways
Light therapy is safe and has measurable effects in the brain
Light therapy could become the first widely-accepted treatment for moderate traumatic brain injury
Raj Gupta, MD, PhD
Director, Ultra-high Resolution | Volume CT Lab ❘ Director, Advanced X-ray Imaging Sciences (AXIS) Center ❘ Associate Professor of Radiology, Harvard Medical School
pioneering study by researchers from the Wellman Center for Photomedicine at
Massachusetts General Hospital (MGH). Senior investigators Rajiv Gupta, MD, PhD,
director of the Ultra-High Resolution Volume CT Lab at MGH and Benjamin Vakoc, PhD,
at the Wellman Center led the study, which was supported by a grant from the
Department of Defense (DOD) and published in JAMA Network Open September 14th.
This study is one of the first, if not the first, prospective, randomized, interventional clinical
trials of near-infrared, low-level light therapy (LLLT) in patients who recently suffered a
moderate brain injury. If further trials support these findings, light therapy could become
the first widely-accepted treatment for this type of injury.
TBI is the leading cause of traumatic injury worldwide, and an estimated 69 million people
experience such an injury every year. However, there are no treatments for this condition
yet, largely because the underlying biological mechanisms are not well understood and it
is so challenging to do studies with actual patients in the acute stage of trauma.
“The Gulf War put TBI in the headlines,” says Gupta, “because body armor had been
greatly improved by then. But there were still brain injuries caused by the shock waves
from high powered explosives.” For a variety of reasons, the number of TBIs has
increased around the globe since then, but effective treatments are still sorely needed.
For this study, a special helmet had to be designed specifically to deliver the therapy, an
undertaking that required a mix of medical, engineering and physics expertise. This
multidisciplinary team included Gupta, a neuroradiologist, Vakoc, an applied physicist,
and others specializing in the development and translation of optical instrumentation to
the clinic and biologic laboratories. Both Gupta and Vakoc are also associate professors
at Harvard Medical School.
“For this study, we designed a practical, near-infrared treatment based on Wellman
Center research and working directly with DOD on the vexing problem of TBI, a condition
faced by so many,” says Rox Anderson, MD, the center’s director.
Another challenge was optimizing the wavelength of the near-infrared LLLT. “Nobody
knows how much light you need to get the optimal effect,” explains Lynn Drake, MD, one
of the study co-authors and director of business development at the Wellman Center.
“We tried to optimize the wavelength, dosing, timing of delivery, and length of exposure.”
This was done through a series of pre-clinical experiments led by Anderson. These
included multiple preclinical studies led by Michael Hamblin, PhD. Anderson and Hamblin
are both co-authors on this paper.
Near-infrared LLLT has already been considered for multiple uses, but to date, few if any
studies of this technology have been tested and none in patients with TBI. It has been
studied in stroke patients and Wellman basic laboratory research suggests it is
neuroprotective through a mechanism mediated by specialized intracellular organs called
mitochondria. It took several years of research at Wellman to understand the basic
mechanism prior to the clinical trial.
The randomized clinical trial included 68 patients with moderate traumatic brain injury
who were divided into two groups. One group received LLLT, via the special helmet,
which delivered the light. Patients in the control group wore the helmet for the same
amount of time, but did not receive the treatment. The helmet was designed by Vakoc’s
team at Wellman. During the study, the subjects’ brains were tested for neuroreactivity
using quantitative magnetic resonance imaging (MRI) metrics and the subjects also
underwent neurocognitive function assessment.
MRI was performed in the acute (within 72 hours of the injury), early subacute (2-3
weeks), and late subacute (approximately three months) stages of recovery. Clinical
assessments were performed during each visit and at six months, using the Rivermead
Post-Concussion Questionnaire, with each item assessed on a five-point scale.
Twenty-eight patients completed at least one LLLT session and none reported any
adverse reactions. In addition, the researchers found that they could measure the effects
of transcranial LLLT on the brain. The MRI studies showed statistically significant
differences in the integrity of myelin surrounding the neurons of treated patients versus
the control group. Both these findings support follow-up trials, especially since there are
no other treatments for these patients.
The study also showed the light does impact the cells. While it is well established that
cells have light receptors, “going into this trial, we had several unanswered questions
such as whether the light would go through the scalp and skull, whether the dose was
sufficient, and whether it would be enough to engage the neural substrates responsible
for repair after TBI,” says Gupta.
It’s important to note, he adds, that for this initial study, the researchers focused on
patients with moderate traumatic brain injury. That helped to ensure their study could
have statistically significant findings because patients in this category are more likely to
demonstrate a measurable effect. “It would be much more difficult to see such changes
in patients with mild injuries and it is quite likely that in patients with severe brain injuries
the effect of light therapy would be confounded by other comorbidities of severe trauma,”
says Gupta.
He adds that researchers are still very early in the development of this therapy, and it is
not known if it could be applied to other types of brain injury, such as chronic traumatic
encephalopathy (CTE), which has received a lot of public attention over the last few
years. CTE is a progressive degenerative disease associated with a history of repetitive
brain trauma such as that experienced by certain types of athletes, most notably football
players.
This study opens up many possibilities for broader use of photomedicine. “Transcranial
LED therapy is a promising area of research, with potential to help various brain disorders
where therapies are limited,” says Margaret Naeser, PhD, a prominent researcher in
photomedicine and research professor of Neurology at Boston University School of
Medicine. She was not affiliated with this particular study.
This research was partially supported by grants from Air Force contract FA8650-17-C-
9113; Army USAMRAA Joint Warfighter Medical Research Program, contract W81XWH-
15-C-0052; and Congressionally Directed Medical Research Program W81XWH-13-2-
0067.
About the Massachusetts General Hospital
Massachusetts General Hospital, founded in 1811, is the original and largest teaching
hospital of Harvard Medical School. The MGH Research Institute conducts the largest
hospital-based research program in the nation, with an annual research budget of more
than $1 billion and comprises more than 8,500 researchers working across more than 30
institutes, centers and departments. In August 2020 the MGH was named #6 in the
nation by U.S. News & World Report in its list of "America’s Best Hospitals."
Beyond 2D: effects of photobiomodulation in 3D tissue-like systems
Beyond 2D: effects of photobiomodulation in 3D tissue-like systems
Polina Y Bikmulina, Nastasia V Kosheleva, Anastasia I Shpichka, Yuri M Efremov, Vladimir I Yusupov, Peter S Timashev, Yury A Rochev
Significance: Currently, various scaffolds with immobilized cells are widely used in tissue engineering and regenerative medicine. However, the physiological activity and cell viability in such constructs might be impaired due to a lack of oxygen and nutrients. Photobiomodulation (PBM) is a promising method of preconditioning cells to increase their metabolic activity and to activate proliferation or differentiation.
Aim: Investigation of the potential of PBM for stimulation of cell activities in hydrogels.
Approach: Mesenchymal stromal cells (MSCs) isolated from human gingival mucosa were encapsulated in modified fibrin hydrogels with different thicknesses and concentrations. Constructs with cells were subjected to a single-time exposure to red (630 nm) and near-infrared (IR) (840 nm) low-intensity irradiation. After 3 days of cultivation, the viability and physiological activity of the cells were analyzed using confocal microscopy and a set of classical tests for cytotoxicity.
Results: The cell viability in fibrin hydrogels depended both on the thickness of the hydrogels and the concentration of gel-forming proteins. The PBM was able to improve cell viability in hydrogels. The most pronounced effect was achieved with near-IR irradiation at the 840-nm wavelength.
Conclusions: PBM using near-IR light can be applied for stimulation of MSCs metabolism and proliferation in hydrogel-based constructs with thicknesses up to 3 mm.
Keywords: fibrin; hydrogel; mesenchymal stromal cells; photobiomodulation; regenerative medicine; tissue engineering.
Photobiomodulation Therapy Promotes
Expansion of Epithelial Colony Forming Units
Photobiomodulation Therapy Promotes Expansion of Epithelial Colony Forming Units
Imran Khan, Praveen R Arany
Objective: This preliminary study examines the effects of low-dose light therapy, also called Photobiomodulation (PBM) therapy, on epithelial colony forming units (eCFUs) in epithelial cells from skin and mucosa to assess their potential to contribute to tissue regeneration. Also, preliminary comparison of basic PBM parameters such as wavelengths, light sources, and dose were evaluated in promoting eCFUs.
Background data: Regenerative medicine is at the brink of exploiting the tremendous potential offered by advances in stem cell biology. The two distinct aspects for utilization of stem cells, either resident (endogenous) or transplanted (exogenous), rely on cells amenable to expansion and being directed toward mature, functional tissues. Despite major progress in fundamental understanding of stem cell pluripotency, there remain fundamental challenges in applying these insights into clinical practice.
Methods: PBM treatments with various devices, wavelengths, and doses were used on two epithelial cell lines and colony forming assays were performed.
Results: This study noted a dose-dependent effect of 810 nm laser on increasing eCFUs, either in terms of size or numbers. Comparisons of different wavelengths and light sources noted better efficacy of collimated and coherent lasers compared to LEDs and broad-band light.
Conclusions: PBM therapy promotes expansion of eCFUs that represent progenitors and stem cell populations capable of contributing to tissue repair and regeneration. Further exploration of the precise mechanisms would allow optimization of PBM clinical protocols to harness the regenerative potential of stem cells for wound healing and other clinical regenerative applications.
Photobiomodulation-Induced Differentiation of
Immortalized Adipose Stem Cells to Neuronal Cells
Photobiomodulation-Induced Differentiation of Immortalized Adipose Stem Cells to Neuronal Cells
Sajan George, Michael R Hamblin, Heidi Abrahamse
Background and objectives:
Transdermal differentiation of human adipose stem cells (ASCs) to other cell types is still a challenge in regenerative medicine. Studies using primary ASCs are also limited as they may undergo replicative senescence during repeated passages in vitro. However, ASCs immortalized (iASCs) with human telomerase enzyme expressing plasmid exhibits a uniform population suitable for differentiation in vitro. A right combination of biological and physical stimuli may induce transdermal differentiation of iASCs into neurons in vitro.
Study design/materials and methods: iASCs were differentiated to free-floating neural stem cell aggregates (neurospheres) using a combination of growth inducers. Cells in these spheres were induced to differentiate into neurons using low-intensity lasers by a process called photobiomodulation (PBM).
Results: Laser at the near infrared (NIR) wavelength 825 nm and fluences 5, 10, and 15 J/cm2 was capable of increasing the differentiation of neurospheres to neurons. Precisely, there was a statistically significant increase in the early neuronal marker at 5 J/cm2 and a much appreciable increase at 15 J/cm2 in correlation with the biphasic dose response of PBM. However, these differentiated cells failed to express late neuronal markers in vitro. Comparison of these differentiating iASCs with the primary ASCs revealed a sharp distinction between the metabolic processes of the primary ASCs, neurospheres, and newly differentiated neurons.
Conclusion: We found that PBM increased the yield of neurons and effected stem cell differentiation through modulation of cellular metabolism and redox status. Our study also identifies that iASCs are an excellent model for analysis of stem cell biology and for performing transdermal differentiation.
Significance: This study demonstrates that a combination of biological and physical inducers can advance the differentiation of adipose stem cells to neurons. We were able to establish the optimal energy for the neuronal differentiation of iASCs in vitro. Lasers Surg. Med.
© 2020 Wiley Periodicals LLC.
Keywords: adipose stem cells; differentiation; laser; metabolism; neurons; photobiomodulation