Photobiomodulation in diabetic rats: Effects on morphological, pancreatic parameters, and glucose homeostasis.

Photobiomodulation (PBM) has therapeutic effects on wound healing, diabetic microangiopathy, and retinopathy. However, little is known about the use of PBM for the treatment of diabetes mellitus (DM). In this context, we aimed to evaluate the effects of PBM on pancreas morphology and insulin and glucose tolerance in an experimental model of DM. Thus, DM was induced by streptozotocin (STZ) (60 mg/kg). Subsequently, the rats were treated with PBM (808 nm and 30 J/cm2 ). After euthanasia, morphometric parameters and immunoreactivity for insulin and 8-OHdG were evaluated in the pancreas. The results showed that treated animals had higher values of body mass and higher values in the number of beta cells in the pancreas. In conclusion, PBM resulted in decreased weight loss in STZ-induced diabetic rats and presented a stimulatory effect on the pancreas of the treated animals, highlighting the promising effects of this therapy in the clinical condition of DM.

Red LED light therapy associated with epidermal growth factor on wound repair process in rats.

Epidermal growth factor (EGF) and light-emitting diode (LED) are currently deployed as promissory treatments for skin repair; however, the mechanisms of their association are not yet evidenced. Thus, the present study aimed to evaluate the effects of combined treatment with EGF and red LED on the wound healing processes in rats. Adult Wistar rats were randomized in control group (CG) wounds without treatment; wounds submitted to EGF treatment (EGF); wounds submitted to LED treatment (LED); wounds submitted to EGF associated with LED treatments (EGF/LED). Treatments were performed immediately after the surgical procedure and each 24 h, totaling 8 sessions. Moreover, LED was applied before EGF treatment at a single point in the center of the wound. Morphological characteristics and the immunoexpression of COX-2, VEGF, and TGF-ß were measured. The results demonstrated that EGF/LED group presented a higher wound healing index. Additionally, all experimental groups presented similar findings in the histological evaluation, the degree of inflammation, and the area of dermis-like tissue. However, for EGF-treated animals (with or without LED), neoepithelial length was higher. Furthermore, all the treated groups decreased COX-2 and increased VEGF immunoexpression, and only EGF/LED group enhanced the TGF-ß protein expression when compared to the untreated group. This research shows that EGF and LED modulate inflammatory process and increase the vascularity. In addition, treatment of EGF associated with LED promoted a more evident positive effect for increasing TGF-ß expression and may be promising resources in the clinical treatment of cutaneous wounds.

Influence of photobiomodulation therapy on the treatment of pulmonary inflammatory conditions and its impact on COVID-19.

We are currently facing a pandemic that continuously causes high death rates and has negative economic and psychosocial impacts. Therefore, this period requires a quick search for viable procedures that can allow us to use safe and non-invasive clinical tools as prophylactic or even adjuvant methods in the treatment of COVID-19. Some evidence shows that photobiomodulation therapy (PBMT) can attenuate the inflammatory response and reduce respiratory disorders similar to acute lung injury (ALI), complications associated with infections, such as the one caused by the new Coronavirus (SARS-CoV-2). Hence, the aim of the present study was to evaluate the influence of PBMT (infrared low-level laser therapy) on the treatment of ALI, one of the main critical complications of COVID-19 infection, in an experimental model in rats. Twenty-four male Wistar rats were randomly allocated to three experimental groups (n = 8): control group (CG), controlled ALI (ALI), and acute lung injury and PBM (ALIP). For treatment, a laser equipment was used (808 nm; 30 mw; 1.68 J) applied at three sites (anterior region of the trachea and in the ventral regions of the thorax, bilaterally) in the period of 1 and 24 h after induction of ALI. For treatment evaluation, descriptive histopathological analysis, lung injury score, analysis of the number of inflammatory cells, and expression of interleukin 1 ß (IL-1ß) were performed. In the results, it was possible to observe that the treatment with PBMT reduced inflammatory infiltrates, thickening of the alveolar septum, and lung injury score when compared to the ALI group. In addition, PBMT showed lower immunoexpression of IL-1ß. Therefore, based on the results observed in the present study, it can be concluded that treatment with PBMT (infrared low-level laser therapy) was able to induce an adequate tissue response capable of modulating the signs of inflammatory process in ALI, one of the main complications of COVID-19.

Intense Pulsed Light on skin rejuvenation: a systematic review.

Aged skin is characterized by appearance of wrinkles, vascular lesions, hyperpigmentation, lentignes, texture, rhytides, and pores. These changes occur under the influence of intrinsic and extrinsic factors, as hormone alterations and exposure to ultraviolet light (UV) irradiation, respectively. Skin changes associated with aging have been assuming an important role in nowadays and bring to affect the quality of life. Intense Pulsed Light (ILP) is a noncollimated, polychromatic, and noncoherent non-surgical cosmetic therapy to skin rejuvenation. This is the first systematic review evaluating ILP treatment on skin rejuvenation evaluated by digital photographs and self-reported treatment efficacy. A PRISMA compliant review includes a search of the databases Scopus and PubMed. Sixteen studies treating 637 participants (with Fitzpatrick skin types I to IV and age varying from 21 to 80 years) were included. Patients were treated a mean of 4.29 sessions (range 3-7). The most studies results showed the efficacy of IPL treatment in telangiectasia, wrinkles, pore, erythema, rhytids, texture, lentigines, hiperpigmentation, and photoaging score. Six studies showed IPL-positive effects in association with other treatment and seven studies showed superior effect of other treatment or association to IPL with other treatment related to IPL alone. Nine studies showed low methodological quality. In conclusion, ILP treatment is effective on skin rejuvenation. However, there is no consensus about the parameters and future studies are needed to sample size limitations, made RCTs with low risk of bias, and improve the methodological quality its. Trial registration: Prospero Systematic Review Registration ID: CRD42021237817.

Effects of photobiomodulation and a physical exercise program on the expression of inflammatory and cartilage degradation biomarkers and functional capacity in women with knee osteoarthritis: a randomized blinded study.

BACKGROUND: The knee osteoarthritis (OA) is a joint disease characterized by degradation of articular cartilage that leads to chronic inflammation. Exercise programs and photobiomodulation (PBM) are capable of modulating the inflammatory process of minimizing functional disability related to knee OA. However, their association on the concentration of biomarkers related to OA development has not been studied yet. The aim of the present study is to investigate the effects of PBM (via cluster) with a physical exercise program in functional capacity, serum inflammatory and cartilage degradation biomarkers in patients with knee OA. METHODS: Forty-two patients were randomly allocated in 3 groups: ESP: exercise + sham PBM; EAP: exercise + PBM and CG: control group. Six patients were excluded before finished the experimental period. The analyzed outcomes in baseline and 8-week were: the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) and the evaluation of serum biomarkers concentration (IL-1ß, IL-6, IL-8, IL-10 e TNF-α, and CTX-II). RESULTS: An increase in the functional capacity was observed in the WOMAC total score for both treated groups (p < 0.001) and ESP presents a lower value compared to CG (p < 0.05) the 8-week post-treatment. In addition, there was a significant increase in IL-10 concentration of EAP (p < 0.05) and higher value compared to CG (p < 0.001) the 8-week post-treatment. Moreover, an increase in IL-1ß concentration was observed for CG (p < 0.05). No other difference was observed comparing the other groups. CONCLUSION: Our data suggest that the physical exercise therapy could be a strategy for increasing functional capacity and in association with PBM for increasing IL-10 levels in OA knee individuals. TRIAL REGISTRATION: ReBEC (RBR-7t6nzr).

Bone substitutes and photobiomodulation in bone regeneration: A systematic review in animal experimental studies.

In general, bone fractures are able of healing by itself. However, in critical situations such as large bone defects, poor blood supply or even infections, the biological capacity of repair can be impaired, resulting in a delay of the consolidation process or even in non-union fractures. Thus, technologies able of improving the process of bone regeneration are of high demand. In this context, ceramic biomaterials-based bone substitutes and photobiomodulation (PBM) have been emerging as promising alternatives. Thus, the present study performed a systematic review targeting to analyze studies in the literature which investigated the effects of the association of ceramic based bone substitutes and PBM in the process of bone healing using animal models of bone defects. The search was conducted from March and April of 2019 in PubMed, Web of Science and Scopus databases. After the eligibility analyses, 16 studies were included in this review. The results showed that the most common material used was hydroxyapatite (HA) followed by Biosilicate associated with infrared PBM. Furthermore, 75% of the studies demonstrated positive effects to stimulate bone regeneration from association of ceramic biomaterials and PBM. All studies used low-level laser therapy (LLLT) device and the most studies used LLLT infrared. The evidence synthesis was moderate for all experimental studies for the variable histological analysis demonstrating the efficacy of techniques on the process of bone repair stimulation. In conclusion, this review demonstrates that the association of ceramic biomaterials and PBM presented positive effects for bone repair in experimental models of bone defects.

Association of photobiomodulation therapy (PBMT) and exercises programs in pain and functional capacity of patients with knee osteoarthritis (KOA): a systematic review of randomized trials.

Knee osteoarthritis (KOA) is a common degenerative disease in which several treatments and treatment associations have been investigated. This review analyzed the efficacy of the association of photobiomodulation therapy (PBMT) and exercises for people with KOA in randomized controlled clinical trials. PubMed, Scopus, and EMBASE databases were searched using the following terms: "knee osteoarthritis," "laser," "low-level laser," "photobiomodulation," "phototherapy," and "exercise." Seven RCT studies involving humans that examined PBMT treatment in association with were found. Most studies used mainly near-infrared PBMT irradiation, with a fluence ranging from 610 mJ/cm2 to 200 J/cm2, 23.55 J to 2400 J total energy per knee, and number of treatment sessions from 10 to 24. In addition, all the protocols included exercises to increase lower limb muscle strength that were performed alone or in association with other types of exercises. However, only 2 studies, considered as a high quality, showed the additional effect of PBMT (lower doses) on an exercise program (involving warming-up, motor learning, balance coordination and strengthening exercises, and stretching) for improvement of pain and functional capacity in people with KOA. This review demonstrates that there is a controversy on the effects PBMT associated with exercises for pain and functional capacity improvement for people with KOA, because there is a heterogeneity between studies in related to PBMT parameters, as dose, number of therapy sessions and the type of PBMT (either LLLT and HILT), and the exercise protocols proposed.

Acute Photobiomodulation Effects Through a Cluster Device on Skeletal Muscle Fatigue of Biceps Brachii in Young and Healthy Males: A Randomized Double-Blind Session.

Objective: The aim of this study was to investigate and compare the acute effects of red and infrared photobiomodulation (PBM) using a cluster device on biceps brachii muscle fatigue in young and healthy males. Background: Vigorous physical activity could lead to muscle fatigue, which compromises motor control and muscle strength and consequently impairs performance. The positive effects of PBM in reducing fatigue onset have been highlighted. However, the better wavelength with cluster devices is not yet established. Methods: A randomized double-blind session was used. Thirty-two young and healthy males were randomized into the control group (CG), red PBM group (RPG), and infrared PBM group (IPG). A PBM cluster device [7 visible diodes (630 nm), 7 infrared diodes (850 nm), 100 mW/diode, 2 W/cm2 power density, 91 J/cm2 energy density, 4 J per point, 28 J total energy, and 40 sec] was applied after muscle fatigue. Muscle fatigue was analyzed by surface electromyography (EMG) recorded from the long head of biceps brachii, blood lactate concentration, and evaluation of the rate of perceived exertion (RPE) using the Borg Scale. The fatigue protocol consisted of a maximum voluntary isotonic contraction of elbow flexion-extension with 75% of one-repetition maximum until exhaustion. The Borg Scale was applied before and at the end of the experiment to measure the RPE. The electromyography fatigue index (EMGFI) was calculated by windows of median frequency from EMG data. Results: EMGFI, blood lactate concentration, and RPE showed no intergroup statistical difference, except the EMGFI delta value that showed a difference between IPG and CG, with a greater value in the CG. However, intragroup comparisons showed that EMGFI decreased in the CG and RPE and lactate concentration increased significantly in all groups. Conclusions: There was no difference between red and infrared PBM in reduction of biceps brachii fatigue. However, the EMGFI delta value was greater in the IPG compared with the CG, suggesting that infrared can be more effective in reducing biceps brachii fatigue.

Marine spongin incorporation into Biosilicate® for tissue engineering applications: An in vivo study.

Biomaterials and bone grafts, with the ability of stimulating tissue growth and bone consolidation, have been emerging as very promising strategies to treat bone fractures. Despite its well-known positive effects of biosilicate (BS) on osteogenesis, its use as bone grafts in critical situations such as bone defects of high dimensions or in non-consolidated fractures may not be sufficient to stimulate tissue repair. Consequently, several approaches have been explored to improve the bioactivity of BS. A promising strategy to reach this aim is the inclusion of an organic part, such as collagen, in order to mimic bone structure. Thus, the present study investigated the biological effects of marine spongin (SPG)-enriched BS composites on the process of healing, using a critical experimental model of cranial bone defect in rats. Histopathological and immunohistochemistry analyzes were performed after two and six weeks of implantation to investigate the effects of the material on bone repair (supplemental material-graphical abstract). Histological analysis demonstrated that for both BS and BS/SPG, similar findings were observed, with signs of material degradation, the presence of granulation tissue along the defect area and newly formed bone into the area of the defect. Additionally, histomorphometry showed that the control group presented higher values for Ob.S/BS (%) and for N.Ob/T.Ar (mm2) (six weeks post-surgery) compared to BS/SPG and higher values of N.Ob/T.Ar (mm2) compared to BS (two weeks post-surgery). Moreover, BS showed higher values for OV/TV (%) compared to BS/SPG (six weeks post-surgery). Also, VEGF immunohistochemistry was increased for BS (two weeks post-surgery) and for BS/SPG (six weeks) compared to CG. TGFb immunostaining was higher for BS compared to CG. The results of this study demonstrated that the BS and BS/SPG scaffolds were biocompatible and able to support bone formation in a critical bone defect in rats. Moreover, an increased VEGF immunostaining was observed in BS/SPG.

Level of pain, muscle strength and posture: effects of PBM on an exercise program in women with knee osteoarthritis - a randomized controlled trial.

To evaluate the effectiveness of an exercise program associated to photobiomodulation (PBM) on pain, postural changes, functionally, and muscular strength in women, one of the risk factors, with knee osteoarthritis (OA). A randomized controlled trial, with a blinded assessor and intention-to-treat analysis and placebo control. Sixty-two participants with knee OA (with confirmed radiological diagnosis) were evaluated for this study. However, 34 were considered eligible and were randomized into two groups: EPPG - exercise and PBM placebo group (n = 17) and EPAG - exercise and PBM active group (n = 16), but one participant was excluded of EPAG. The exercise program and PBM (808 nm, 100 mW/point, 4 J/point, 56 J total, 91 J/cm2) were realized twice a week, during 8 weeks. West Ontario and the McMaster University Osteoarthritis Index (WOMAC) and Lequesne questionnaires, 1-repetition maximum test (1-RM) and posture evaluation software (SAPO) were used to analyze the effects of the therapies. In intragroup analysis, a significant improvement in pain WOMAC (p < 0.001), stiffness (p < 0.001), function (p < 0.001), Lequesne (p < 0.001), and 1-RM (all muscle groups) (p < 0.001) were observed. In this study, the exercise program improved pain, function, and muscle strength of all the participants. However, PBM, in the parameters used, did not optimize the effects of the exercise program in women with knee OA.

Low-Level Laser Therapy and Spinal Cord Injury: Effects of 3 Different Fluences in the Intermediate Period of Repair in an Experimental Model in Rats

Abstract The aim of this study was to evaluate the effectiveness of 3 different fluences of low-level laser therapy (LLLT) in intermediate period of spinal cord repair using an experimental model in rats. Thirty two rats were randomly divided into four experimental groups: Control Group (CG); Laser treated group 500 J/cm² (L-500); Laser treated group 750 J/cm² (L-750) and Laser treated group 1000 J/cm² (L-1000). Spinal cord injury (SCI) was performed by an impactor equipment (between 9th and 10th thoracic vertebrae), with a pressure of 150 kdyn. Afterwards, the injured region was irradiated daily for 14 consecutive sessions, using an 808 nm laser, at the respective fluence of each experimental groups. Locomotor function and tactile sensitivity were performed on days 1 and 15 post-surgery. Animals were euthanized 15 days post-surgery and samples were retrieved for histological and immunohistochemistry analysis. Functional behavior and tactile sensitivity were improved after laser irradiation. Moreover, higher fluencies of LLLT reduced the volume of injury. Additionally, LLLT produced a decreased CD-68 expression. These results demonstrated that, for an intermediate period of SCI repair, LLLT at higher fluences, was effective in promoting functional recovery and modulating the inflammatory process in the spinal cord of rats after traumatic SCI.

Bioglass/PLGA associated to photobiomodulation: effects on the healing process in an experimental model of calvarial bone defect.

Bioactive glasses (BG) are known for their ability to bond to bone tissue. However, in critical situations, even the osteogenic properties of BG may be not enough to induce bone consolidation. Thus, the enrichment of BG with polymers such as Poly (D, L-lactic-co-glycolic) acid (PLGA) and associated to photobiomodulation (PBM) may be a promising strategy to promote bone tissue healing. The aim of the present study was to investigate the in vivo performance of PLGA supplemented BG, associated to PBM therapy, using an experimental model of cranial bone defect in rats. Rats were distributed in 4 different groups (Bioglass, Bioglass/PBM, Bioglas/PLGA and BG/PLGA/PBM). After the surgical procedure to induce cranial bone defects, the pre-set samples were implanted and PBM treatment (low-level laser therapy) started (808 nm, 100 mW, 30 J/cm2). After 2 and 6 weeks, animals were euthanized, and the samples were retrieved for the histopathological, histomorphometric, picrosirius red staining and immunohistochemistry analysis. At 2 weeks post-surgery, it was observed granulation tissue and areas of newly formed bone in all experimental groups. At 6 weeks post-surgery, BG/PLGA (with or without PBM) more mature tissue around the biomaterial particles. Furthermore, there was a higher deposition of collagen for BG/PLGA in comparison with BG/PLGA/PBM, at second time-point. Histomorphometric analysis demonstrated higher values of BM.V/TV for BG compared to BG/PLGA (2 weeks post-surgery) and N.Ob/T.Ar for BG/PLGA compared to BG and BG/PBM (6 weeks post-surgery). This current study concluded that the use of BG/PLGA composites, associated or not to PBM, is a promising strategy for bone tissue engineering.

The effect of low-level laser therapy and physical exercise on pain, stiffness, function, and spatiotemporal gait variables in subjects with bilateral knee osteoarthritis: a blind randomized clinical trial.

Objective: To evaluate the effects of individual and combination therapies (low-level laser therapy and physical exercises) on pain, stiffness, function, and spatiotemporal gait variables in subjects with bilateral knee osteoarthritis (OA).Methods: Subjects with knee OA (Grades 1-3) were evaluated and randomized into four groups: Control Group (CG), untreated; Laser Group (LG), treated with laser at 808 nm, 5.6 J; Exercise Group (EG), treated with exercise; and Laser + Exercise Group (LEG), treated with laser and exercises. The treatment was carried out twice a week for 2 months. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire was applied for evaluation and reevaluation; evaluation of spatiotemporal gait variables was performed using GAITRite equipment.Results: The EG showed significant improvement in pain (p = 0.006) and function (p = 0.01) according to WOMAC. Regarding gait variables, in intergroup analysis after 8 weeks all groups receiving intervention showed a significant increase in gait speed: LG versus CG (p = 0.03); EG versus CG (p = 0.04) and LEG versus CG (p = 0.005). Only the group treated with laser + exercise showed a significant increase (p = 0.009) in the cadence and duration of single right limb support (p = 0.04), and only the groups treated with exercise and laser + exercise showed significant decreases in the duration of right limb support (p = 0.035 and p = 0.003, respectively), compared to the CG.Conclusions: The group treated only with exercise showed improvement in WOMAC questionnaire scores. Regarding the gait variables, all groups undergoing the interventions showed increases in the gait speed compared to the CG. The laser and exercise combination therapy provided the best results for the other gait variables (cadence and duration of right limb support and duration of single right limb support).Implications for rehabilitationThere are differences in gait patterns in patients with knee OA, including decreased gait speed, cadence, and step length.The results shown in the present study provide additional information about the physical therapy approaches that should be chosen during clinical practical to improve gait performance in individuals with knee osteoarthritis.The improvement in gait performance is a relevant issue due to the fact that is associated to physical independence and better quality of life.

Low-level laser therapy modulates demyelination in mice.

There are no effective therapies for remyelination. Low-level laser therapy (LLLT) has been found advantageous in neurogenesis promotion, cell death prevention, and modulation of inflammation in central and peripheral nervous system models. The purpose of this study was to analyse LLLT effects on cuprizone-induced demyelination. Mice were randomly distributed into three groups: Control Laser (CTL), Cuprizone (CPZ), and Cuprizone Laser (CPZL). Mice from CPZ and CPZL groups were exposed to a 0.2% cuprizone oral diet for four complete weeks. Six sessions of transcranial laser irradiation were applied on three consecutive days, during the third and fourth weeks, with parameters of 36 J/cm2, 50 mW, 0.028 cm2 spot area, continuous wave, 1 J, 20 s, 1.78 W/cm2 in a single point equidistant between the eyes and ears of CTL and CPZL mice. Motor coordination was assessed by the rotarod test. Twenty-four hours after the last laser session, all animals were euthanized, and brains were extracted. Serum was obtained for lactate dehydrogenase toxicity testing. Histomorphological analyses consisted of Luxol Fast Blue staining and immunohistochemistry. The results showed that laser-treated animals presented motor performance improvement, attenuation of demyelination, increased number of oligodendrocyte precursor cells, modulated microglial and astrocytes activation, and a milder toxicity by cuprizone. Although further studies are required, it is suggested that LLLT represents a feasible therapy for demyelinating diseases.

Interleukin-10 and collagen type II immunoexpression are modulated by photobiomodulation associated to aerobic and aquatic exercises in an experimental model of osteoarthritis.

The aim of this study was to compare the effects of photobiomodulation (PBM) associated with an aerobic and an aquatic exercise training on the degenerative process related to osteoarthritis (OA) in the articular cartilage in rats. Fifty male Wistar rats were randomly divided into 5 groups: OA control group (CG), OA plus aerobic training group (AET), OA plus aquatic training group (AQT), OA plus aerobic training associated with PBM group (AETL), OA plus aquatic training associated with PBM group (AQTL). The aerobic training (treadmill; 16 m/min; 50 min/day) and the aquatic training (water jumping; 50-80% of their body mass) started 4 weeks after the surgery and they were performed 3 days/week for 8 weeks. Moreover, PBM was performed after the physical exercise trainings on the left joint. Morphological characteristics and immunoexpression of IL-10, TGF-ß, and collagen type I (Col I) and II (Col II) of the articular cartilage were evaluated. The results showed that all the treated groups (exercise and PBM) presented less intense signs of degradation (measured by histopathological analysis and OARSI grade system). Additionally, aerobic and aquatic exercise training rats (associated or not with PBM) showed increased IL-10 (AET p = 0.0452; AETL p = 0.03; AQTL p = 0.0193) and Col II (AET p = 0.012; AQT p = 0.0437; AETL p = 0.0001; AQTL p = 0.0001) protein expression compared to CG. Furthermore, a statistically higher TGF-ß expression was observed in AET (p = 0.0084) and AETL (p = 0.0076) compared to CG. These results suggest that PBM associated with aerobic and aquatic exercise training were effective in mediating chondroprotective effects and maintaining the integrity of the articular tissue in the knees of OA rats.

Photobiomodulation (PBM) therapy at 904 nm mitigates effects of exercise-induced skeletal muscle fatigue in young women.

Muscle fatigue is a process influenced by several mechanisms such as concentration of metabolic substrates, changes in blood flow, and increases in reactive oxygen species that impair contractile muscle function. In this context, photobiomodulation has been investigated for preventing muscle fatigue, with reports of positive effects on muscle performance. This study aimed to investigate the effects of 904-nm LASER photobiomodulation on rectus femoris muscle performance in young women. Eighteen young women participated in a randomized, participant and assessor-blinded crossover trial with placebo control. Active LASER (904 nm, 60 mW, 250 Hz, 3.6 J per diode, total dose of 129.6 J) intervention was applied prior to an isokinetic fatigue protocol consisting of a set of 60 concentric quadricep contractions at a constant dynamometer angular velocity of 180°/s. Compared to placebo, LASER photobiomodulation significantly reduced muscle fatigue across a range of indicators including reduced ratings of perceived exertion (P = 0.0139), and increased electromyographic fatigue index (EFI) (P = 0.005). The isokinetic dynamometer performance analysis demonstrated that LASER photobiomodulation increased peak torque (P = 0.04), time to peak torque (P = 0.042), total work (P = 0.032), average power (P = 0.0007), and average peak torque (P = 0.019) between both experimental conditions. No significant difference was observed for work fatigue index (P = 0.29) or for lactate concentration (P > 0.05). Photobiomodulation at 904 nm was effective in reducing fatigue levels and increasing muscle performance in young active women but had no effect on lactate levels.

Chondroitin sulfate and glucosamine sulfate associated to photobiomodulation prevents degenerative morphological changes in an experimental model of osteoarthritis in rats.

The aim of this study was to compare the effects of combined treatment with chondroitin sulfate and glucosamine sulfate (CS/Gl) and photobiomodulation (PBM) on the degenerative process related to osteoarthritis (OA) in the articular cartilage in rats. Forty male Wistar rats were randomly divided into four groups: OA control group (CG); OA animals submitted to PBM treatment (PBM); OA animals submitted to CS/Gl treatment (CS/Gl); OA submitted to CS/GS associated with PBM treatments (GS/Gl + PBM). The CS/Gl started 48 h after the surgery, and they were performed for 29 consecutive days. Moreover, PBM was performed after the CS/Gl administration on the left joint. Morphological characteristics and immunoexpression of interleukin 10 (IL-10) and 1 beta (IL-1ß) and collagen type II (Col II) of the articular cartilage were evaluated. The results showed that all treated groups (CS/Gl and PBM) presented attenuation signs of degenerative process (measured by histopathological analysis) and lower density chondrocytes [PBM (p = 0.0017); CS/Gl (p = 0.0153) and CS/Gl + PBM (p = 0.002)]. Additionally, CS/Gl [associated (p = 0.0089) or not with PBM (p = 0.0059)] showed significative lower values for OARSI grade evaluation. Furthermore, CS/GS + PBM decreased IL-1ß protein expression (p = 0.0359) and increased IL-10 (p = 0.028) and Col II imunoexpression (p = 0.0204) compared to CG. This study showed that CS/Gl associated with PBM was effective in modulating inflammatory process and preventing the articular tissue degradation in the knees OA rats.

Efeito agudo do laser de baixa potência na fadiga do bíceps braquial de atletas de voleibol / Acute effect of low-power laser in fatigue of biceps brachii of volleyball athletes / Efecto agudo del láser de baja potencia en la fatiga del bíceps braquial de atletas de voleibol

RESUMO Introdução: A laserterapia de baixa potência tem entre seus propósitos auxiliar a recuperação de tecidos biológicos, atenuando os efeitos da fadiga muscular e contribuindo com a melhora do desempenho em atletas. Aspectos metodológicos ainda limitam as conclusões do efeito agudo da laserterapia sobre o desempenho muscular. Objetivo: Verificar o efeito agudo do laser terapêutico de baixa potência na fadiga induzida do bíceps braquial de atletas de voleibol. Métodos: Este foi um estudo randomizado e duplo-cego, aprovado pelo Comitê de Ética da UNESP de Marília. Participaram do estudo 19 atletas de voleibol de ambos os sexos. Realizou-se coleta de dados eletromiográficos do músculo bíceps braquial no exercício isométrico de flexão de cotovelo antes e após a aplicação do laser terapêutico. Um haltere com 75% do pico de força, obtido por uma célula de carga, foi utilizado para o protocolo de fadiga. Em seguida, os voluntários foram submetidos à aplicação do laser (ativo ou placebo) em seis pontos do músculo bíceps braquial. Os dados eletromiográficos foram analisados no domínio da frequência, utilizando-se o software Myosystem®. Verificou-se a distribuição de normalidade dos dados pelo teste de Shapiro-Wilk, e utilizou-se Anova (split plot) de medidas repetidas a fim de testar a interação entre tempo e grupo. Resultados: Para nenhuma das variáveis analisadas foi observada interação significativa entre grupo e tempo, indicando que o grupo irradiado não apresentou vantagens com relação ao grupo placebo. Conclusão: Após o protocolo de fadiga proposto, uma única aplicação de laser de baixa potência não foi suficiente para produzir efeitos positivos no desempenho de força e no sinal eletromiográfico do músculo bíceps braquial de atletas de voleibol.

ABSTRACT Introduction: Low-power laser therapy has among its aims to aid the recovery of biological tissues, attenuating the effects of muscle fatigue and contributing to the improvement of performance in athletes. Methodological aspects still limit the conclusions of the acute effect of laser therapy on muscular performance. Objective: To verify the acute effect of low-power therapeutic laser in the induced fatigue in biceps brachii of volleyball athletes. Methods: This was a randomized double-blind study, approved by Institutional Review Board of UNESP, Marília. Nineteen volleyball athletes of both sexes participated in this study. Electromyographic data were collected from the biceps brachii muscle in isometric exercise of the elbow flexion before and after the application of the therapeutic laser. A dumbbell with 75% of the force peak, obtained by a load cell, was used for the fatigue protocol. The volunteers then underwent laser (active or placebo) application on six points of the biceps brachii muscle. The EMG data were analyzed in the frequency domain using the Myosystem ® software. The distribution of normality was verified by the Shapiro-Wilk test, and repeated measures ANOVA (split plot) was used to test the interaction between time and group. Results: No significant interaction between group and time was observed for any analyzes variables, indicating that the irradiated group did not show advantages over the placebo group. Conclusion: After the proposed fatigue protocol, a single low-power laser application was not sufficient to produce positive effects on strength performance and on the electromyographic signal of the biceps brachii muscle of volleyball athletes.

RESUMEN Introducción: La láserterapia de baja potencia tiene entre sus propósitos auxiliar la recuperación de los tejidos biológicos, atenuando los efectos de la fatiga muscular y contribuyendo con la mejora del desempeño en atletas. Los aspectos metodológicos todavía limitan las conclusiones del efecto agudo de la láserterapia sobre el rendimiento muscular. Objetivo: Verificar el efecto agudo del láser terapéutico de baja potencia en la fatiga inducida del bíceps braquial de atletas de voleibol. Métodos: Fue un estudio aleatorizado y doble ciego, aprobado por el Comité de Ética de la UNESP de Marília. Participaron del estudio 19 atletas de voleibol de ambos sexos. Se realizó la recolección de datos electromiográficos del músculo bíceps braquial en ejercicio isométrico de flexión de codo antes y después de la aplicación del láser terapéutico. Se utilizó una mancuerna con un 75% del pico de fuerza, obtenido por una célula de carga para el protocolo de fatiga. A continuación, los voluntarios fueron sometidos a la aplicación del láser (activo o placebo) en seis puntos del músculo bíceps braquial. Los datos electromiográficos se analizaron en el ámbito de la frecuencia, utilizando el software Myosystem ® . Se verificó la distribución de la normalidad de los datos por la prueba de Shapiro-Wilk, y se utilizó Anova (split plot) de medidas repetidas para probar la interacción entre tiempo y grupo. Resultados: Para ninguna de las variables analizadas se observó interacción significativa entre grupo y tiempo, indicando que el grupo irradiado no presentó ventajas con relación al grupo placebo. Conclusión: Después del protocolo de fatiga propuesto, una única aplicación láser de baja potencia no fue suficiente para producir efectos positivos en el desempeño de fuerza y en las señales electromiográficas del músculo bíceps braquial de atletas de voleibol.

Non-ablative radiofrequency associated or not with low-level laser therapy on the treatment of facial wrinkles in adult women: A randomized single-blind clinical trial.

OBJECTIVES: The objective of this study was to evaluate the effects of Non-ablative Radiofrequency (RF) associated or not with low-level laser therapy (LLLT) on aspect of facial wrinkles among adult women. METHODS: Forty-six participants were randomized into three groups: Control Group (CG, n = 15), RF Group (RG, n = 16), and RF and LLLT Group (RLG, n = 15). Every participant was evaluated on baseline (T0), after eight weeks (T8) and eight weeks after the completion of treatment (follow-up). They were photographed in order to classify nasolabial folds and periorbital wrinkles (Modified Fitzpatrick Wrinkle Scale and Fitzpatrick Wrinkle Classification System, respectively) and improvement on appearance (Global Aesthetic Improvement Scale). Photograph analyses were performed by 3 blinded evaluators. RESULTS: Classification of nasolabial and periorbital wrinkles did not show any significant difference between groups. Aesthetic appearance indicated a significant improvement for nasolabial folds on the right side of face immediately after treatment (p = 0.018) and follow-up (p = 0.029) comparison. RG presented better results than CG on T8 (p = 0.041, ES = -0.49) and on follow-up (p = 0.041, ES = -0.49) and better than RLG on T8 (p = 0.041, ES = -0.49). RLG presented better results than CG on follow-up (p = 0.007, ES = -0.37). CONCLUSION: Nasolabial folds and periorbital wrinkles did not change throughout the study; however, some aesthetic improvement was observed. LLLT did not potentiate RF treatment.

Effects of different fluences of low-level laser therapy in an experimental model of spinal cord injury in rats.

The aim of this study was to evaluate the in vivo response of different fluences of low-level laser therapy (LLLT) on the area of the injury, inflammatory markers, and functional recovery using an experimental model of traumatic spinal cord injury (SCI). Thirty two rats were randomly divided into four experimental groups: control group (CG), laser-treated group 500 J/cm2 (L-500), laser-treated group 750 J/cm2 (L-750), and laser-treated group 1000 J/cm2 (L-1000). SCI was performed by an impactor equipment (between the ninth and tenth thoracic vertebrae), with a pressure of 150 kdyn. Afterwards, the injured region was irradiated daily for seven consecutive sessions, using an 808-nm laser, at the respective fluence of each experimental groups. Motor function and tactile sensitivity were performed on days 1 and 7 post-surgery. Animals were euthanized on the eighth day after injury, and the samples were retrieved for histological and immunohistochemistry analyses. Functional evaluation and tactile sensitivity were improved after LLLT, at the higher fluence. Additionally, LLLT, at 750 and 1000 J/cm2, reduces the lesion volume and modulates the inflammatory process with decrease of CD-68 protein expression. These results suggest that LLLT at higher doses was effective in promoting functional recovery and modulating inflammatory process in the spinal cord of rats after SCI.