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Made available in DSpace on 2020-12-10T20:04:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-06-26 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Background:Photobiomodulation therapy (PBMT) and creatine (Cr) intake have been used in conjunction with heavy training, but little is known about their possible effects during a long-term training program. Objective:We assessed long-term use of PBMT and Cr in an exercise training program. Methods:Twenty-five male Wistar rats weighing similar to 300 g were randomly allocated to one of five groups: a nontraining control group, a training group, a training group receiving Cr, a training group receiving PBMT, and a training group receiving both PBMT and Cr. The training program consisted of 12 weeks of daily swimming training. PBMT was delivered in six points with a laser device (808 nm, 100 mW, 30 s per point of irradiation, 3 J, 75 J/cm(2)). Results:All training groups showed significantly higher peak force and longer time to 50% decay of force, and lower creatine kinase (CK) levels than the nontraining control group, thus confirming the benefit of the training program. In all outcomes related to muscle performance, the groups receiving PBMT with or without Cr supplement performed significantly better (p < 0.05) peak force and time of force decay during an electrical stimulation protocol than all the other groups. In addition, CK levels were also significantly lower for the PBMT groups than for the other groups. Conclusions:We conclude that PBMT alone or in conjunction with Cr supplement during a 12-week training program resulted in significantly better muscle performance and lower levels of CK, a biochemical marker of muscle damage. Sao Paulo State Univ UNESP, Postgrad Program Movement Sci, Lab Physiol & Sport Performance LAFIDE, Dept Phys Educ, Ave Eng Luiz Edmundo Carrijo Coube, BR-17033360 Bauru, SP, Brazil Univ Brasil, Postgrad Program Biomed Engn, Sao Paulo, SP, Brazil UNESP, Med Sch, Postgrad Program Pathophysiol, Med Clin, Botucatu, SP, Brazil Univ Bergen, Dept Global Publ Hlth & Primary Care, Physiotherapy Res Grp, Bergen, Norway Univ Vale Paraiba UNIVAP, Lab Biophoton & Expt Therapeut, Inst Res & Dev, Sao Jose Dos Campos, SP, Brazil UNINOVE Appl Biophoton Hlth Sci, Sao Paulo, SP, Brazil Sao Paulo State Univ UNESP, Postgrad Program Movement Sci, Lab Physiol & Sport Performance LAFIDE, Dept Phys Educ, Ave Eng Luiz Edmundo Carrijo Coube, BR-17033360 Bauru, SP, Brazil UNESP, Med Sch, Postgrad Program Pathophysiol, Med Clin, Botucatu, SP, Brazil FAPESP: 2017/21724-8 FAPESP: 2019/17445-1

Background: Adipose tissue is the main energy storage tissue in the body. Its catabolic and anabolic responses depend on several factors, such as nutritional status, metabolic profile, and hormonal...

Tendinopathy is characterized by pain, edema, and structural changes in tendon tissue.In this animal study we decided to compare the short- and medium-term effects of low-level laser therapy (LLLT), dexamethasone, and diclofenac on inflammation and tendon tissue repair in collagenase-induced tendinitis.Two hundred five female Wistar rats were randomly divided into five groups. Animals in the control group were given a saline injection and the experimental groups received a collagenase injection (100 μg/tendon) in the peritendinous Achilles and received no treatment, LLLT (3 J, 810 nm, 100 mW), diclofenac (1.1 mg/kg), or dexamethasone (0.02 mg/kg). Histological analyses were performed at 10 time points up to 60 days (n = 5/group each time point), and included an assessment of the severity of inflammation, collagen fiber content, and organization.Collagenase injection induced a severe inflammatory reaction with significant reduction in collagen content for 48 h, and disorientation of collagen fibers lasting between 14 and 21 days. Diclofenac and dexamethasone reduced inflammatory signs during the first 2 days, although there was prolongation of the inflammatory phase and slower normalization of tendon quality, particularly in the dexamethasone group. LLLT prevented hemorrhage, reduced inflammation severity, and preserved tendon morphology compared with the other groups.LLLT showed a significant superiority over commonly used anti-inflammatory pharmaceutical agents in acute collagenase-induced tendinitis.

Low-level laser therapy (LLLT) and cryotherapy are widely used treatments in the acute phase of tendon injury. The aim of this study was to investigate the interaction of these two treatments on tendon inflammation and mechanical properties.Six groups of six Wistar rats were used in this study. The Achilles tendons of the healthy control group were not subjected to injury or treatment. The tendons of the injured nontreated group (ING) were injured, but not treated. The remaining four groups were injured and subjected to LLLT, cryotherapy, LLLT first/cryotherapy, or cryotherapy first/LLLT. All treatments were performed at 1 h post-trauma. Inflammatory mediators, tendon histology, and biomechanical properties were assessed at 24 h post-trauma by comparing the treatment groups with the ING.In all treatment groups, the inflammatory process shifted in an anti-inflammatory direction compared with the ING. Significant alterations in cytokine expression were found in only the LLLT group (↓IL-1β) and the combined intervention groups (↓IL-1β, ↓TNF-α, ↑IL-6). It was also found that cryotherapy followed by LLLT was the only treatment that significantly (p 0.05) improved the biomechanical parameters of force (N) and displacement (mm) at the tendon rupture and corresponded with the best histological scores of all of the treatment groups.Our results demonstrate that cryotherapy in combination with LLLT can produce an anti-inflammatory "add-on" effect. The order of therapy administration seems essential, as superior histology and biomechanical results were found in the cryotherapy first/LLLT group.

Objective: The aim of present study was to evaluate whether low-level laser therapy (LLLT) can reverse the impaired wound healing process in diabetic rats. Background data: Impaired wound healing in diabetic patients represents a major health problem. Recent studies have indicated that LLLT may improve wound healing in diabetic rats, but the optimal treatment parameters are still unknown. Materials and methods: Male Sprague–Dawley rats (n=21) were randomly divided into three groups: a healthy control group, a diabetic sham-treated group, and a diabetic LLLT-treated group. Diabetes mellitus was then induced by streptozotocin administration to the two diabetic groups. One 4 cm long full thickness skin incision and one full thickness circular excision (diameter=4 mm) were performed on the back of each rat. An infrared 810 nm laser with an output of 30 mW, a power density of 30 mW/cm2, and a spot size of 1 cm2 was used to irradiate each wound for 30 sec (daily dose of 0.9 J/cm2/wound/day). Results: In diabetic rats, the histology of LLLT-treated excisions revealed a similar healing response to that in nondiabetic controls, with significantly more mature granulation tissue than in the sham-treated diabetic control group. LLLT reduced the loss of tensile strength, and increased the incision wound stiffness significantly compared with sham-irradiated rats, but this did not achieve the same level as in the nondiabetic controls. Conclusions: Our study demonstrates that infrared LLLT can improve wound healing in diabetic rats. Nevertheless, further research needs to be performed to evaluate the exact underlying mechanism and to further optimize LLLT parameters for clinical use.

The objective of this review was to systematically identify experimental studies of non-ablative laser irradiation (LI) on peripheral nerve morphology, physiology, and function. The findings were then evaluated with special reference to the neurophysiology of pain and implications for the analgesic effects of low-level laser therapy (LLLT).LLLT is used in the treatment of pain, and laser-induced neural inhibition has been proposed as a mechanism. To date, no study has systematically evaluated the effects of LI on peripheral nerve, other than those related to nerve repair, despite the fact that experimental studies of LI on nerves have been conducted over the past 25 years.We searched computerized databases and reference lists for studies of LI effects on animal and human nerves using a priori inclusion and exclusion criteria.We identified 44 studies suitable for inclusion. In 13 of 18 human studies, pulsed or continuous wave visible and continuous wave infrared (IR) LI slowed conduction velocity (CV) and/or reduced the amplitude of compound action potentials (CAPs). In 26 animal experiments, IR LI suppressed electrically and noxiously evoked action potentials including pro-inflammatory mediators. Disruption of microtubule arrays and fast axonal flow may underpin neural inhibition.This review has identified a range of laser-induced inhibitory effects in diverse peripheral nerve models, which may reduce acute pain by direct inhibition of peripheral nociceptors. In chronic pain, spinal cord changes induced by LI may result in long-term depression of pain. Incomplete reporting of parameters limited aggregation of data.

This study was designed to study the effect of an infrared low-level laser (GaAs lambda = 904 nm, 4 mW) on inflammatory cell migration in lipopolysaccharide (LPS)-induced peritonitis in mice.It has been suggested that red wavelengths of low-level laser therapy (LLLT) can exert anti-inflammatory effects, but little is known about the anti-inflammatory effects of infrared lasers. Peritonitis is a potentially life-threatening inflammatory condition that may be suitable for studying anti-inflammatory effects of infrared lasers.Sixty male mice were randomly divided into five groups, and one group was given an intraperitoneal sterile saline injection. In the remaining four groups, peritonitis was induced by an intraperitoneal LPS injection. Animals in three of the LPS groups were irradiated at a single point over the peritoneum with doses of 3 J/cm(2), 7.5 J/cm(2), and 15 J/cm(2), respectively. The fourth group injected with LPS was an LPS-control group.At 6 hours after injection the groups irradiated with doses of 3 J/cm(2) and 7.5 J/cm(2) had a reduced number of neutrophil cells in the peritoneal cavity compared with the LPS-control group, and there were significant differences between the number of neutrophils in the peritoneal cavity between the LPS-control group and groups irradiated with doses of 3 J/cm(2) (-42%) and 7.5 J/cm(2) (-70%). In the group irradiated with 15 J/cm(2), neutrophil cell counts were lower than, but not significantly different from, LPS controls (-38%; p = 0.07). At 24 hours after injection, both neutrophil and total leukocyte cell counts were lower in all the irradiated groups than in the LPS controls. The 3-J/cm(2) exposure group showed the best results at 24 hours, with reductions of 77% in neutrophil and 49% in leukocyte counts.Low-level laser therapy (904 nm) can reduce inflammatory cell migration in mice with LPS-induced peritonitis in a dose-dependent manner.

We designed an animal pleurisy study to assess if the anti-inflammatory effect of photoradiation could be affected by concomitant use of the cortisol antagonist mifepristone.Although interactions between photoradiation and pharmacological agents are largely unknown, parallel use of steroids and photoradiation is common in the treatment of inflammatory disorders such as arthritis and tendinitis.Forty BALB/c male mice were randomly divided in five groups. Inflammation was induced by carrageenan administered by intrathoracic injections. Four groups received carrageenan, and one control group received injections of sterile saline solution. At 1, 2, and 3 h after injections, photoradiation irradiation was performed with a dose of 7.5 J/cm(2). Two of the carrageenan-injected groups were pre-treated with orally administered mifepristone.Total leukocyte cell counts revealed that in carrageenan-induced pleurisy, photoradiation significantly reduced the number of leukocyte cells (p0.0001, mean 34.5 [95% CI: 32.8-36.2] versus 87.7 [95% CI: 81.0-94.4]), and that the effect of photoradiation could be totally blocked by adding the cortisol antagonist mifepristone (p0.0001, mean 34.5 [95% CI: 32.1-36.9] versus 82.9 [95%CI: 70.5-95.3]).The steroid receptor antagonist mifepristone significantly inhibited the anti-inflammatory effect of photoradiation. Commonly used glucocorticoids are also known to down-regulate steroid receptors, and further clinical studies are necessary to elucidate how this interaction may decrease the effect size of photoradiation over time. For this reason, we also suggest that, until further clinical data can be provided, clinical photoradiation trials should exclude patients who have received steroid therapy within 6 months before recruitment.

The aim of this study was to review the biological and clinical short-term effects of photoradiation in acute pain from soft-tissue injury.It is unclear if and how photoradiation can reduce acute pain.Literature search of (i) controlled laboratory trials investigating potential biological mechanisms for pain relief and (ii) randomized placebo-controlled clinical trials which measure outcomes within the first 7 days after acute soft-tissue injury.There is strong evidence from 19 out of 22 controlled laboratory studies that photoradiation can modulate inflammatory pain by reducing levels of biochemical markers (PGE(2), mRNA Cox 2, IL-1beta, TNFalpha), neutrophil cell influx, oxidative stress, and formation of edema and hemorrhage in a dose-dependent manner (median dose 7.5 J/cm(2), range 0.3-19 J/cm(2)). Four comparisons with non-steroidal anti-inflammatory drugs (NSAIDs) in animal studies found optimal doses of photoradiation and NSAIDs to be equally effective. Seven randomized placebo-controlled trials found no significant results after irradiating only a single point on the skin overlying the site of injury, or after using a total energy dose below 5 Joules. Nine randomized placebo-controlled trials (n = 609) were of acceptable methodological quality, and irradiated three or more points and/or more than 2.5 cm(2) at site of injury or surgical incision, with a total energy of 5.0-19.5 Joules. Results in these nine trials were significantly in favor of photoradiation groups over placebo groups in 15 out of 18 outcome comparisons. Poor and heterogeneous data presentation hampered statistical pooling of continuous data. Categorical data of subjective improvement were homogeneous (Q-value = 7.1) and could be calculated from four trials (n = 379) giving a significant relative risk for improvement of 2.7 (95% confidence interval [CI], 1.8-3.9) in a fixed effects model.photoradiation can modulate inflammatory processes in a dose-dependent manner and can be titrated to significantly reduce acute inflammatory pain in clinical settings. Further clinical trials with adequate photoradiation doses are needed to precisely estimate the effect size for photoradiation in acute pain.

The aim of this study was to investigate if low-level laser therapy (LLLT) can modulate acute inflammation and tumor necrosis factor (TNFalpha) levels.Drug therapy with TNFalpha-inhibitors has become standard treatment for rheumatoid arthritis, but it is unknown if LLLT can reduce or modulate TNFalpha levels in inflammatory disorders.Two controlled animal studies were undertaken, with 35 male Wistar rats randomly divided into five groups each. Rabbit antiserum to ovalbumin was instilled intrabronchially in one of the lobes, followed by the intravenous injection of 10 mg of ovalbumin in 0.5 mL to induce acute lung injury. The first study served to define the time profile of TNFalpha activity for the first 4 h, while the second study compared three different LLLT doses to a control group and a chlorpromazine group at a timepoint where TNFalpha activity was increased. The rats in LLLT groups were irradiated within 5 min at the site of injury by a 650-nm Ga-Al-As laser.There was a time-lag before TNFalpha activity increased after BSA injection. TNFalpha levels increased fromor =6.9 (95% confidence interval [CI], 5.6-8.2) units/mL in the first 3 h to 62.1 (95% CI, 60.8-63.4) units/mL (p0.001) at 4 h. An LLLT dose of 0.11 Joules administered with a power density of 31.3 mW/cm(2) in 42 sec significantly reduced TNFalpha level to 50.2 (95% CI, 49.4-51.0), p0.01 units/mL versus control. Chlorpromazine reduced TNFalpha level to 45.3 (95% CI, 44.0-46.6) units/mL, p0.001 versus control.LLLT can reduce TNFalpha expression after acute immunocomplex lung injury in rats, but LLLT dose appears to be critical for reducing TNFalpha release.

The aim of this study was to test if a conclusion in a systematic review of low-level laser therapy (LLLT) for osteoarthritis from the Cochrane Library was valid and robust.Health policy decisions often rely on conclusions from the Cochrane Database of Systematic Reviews for approval of new therapies, although their validity for controversial non-pharmacological treatment has been questioned.Validity was tested against a nine-item checklist for systematic reviews. Review selections were analyzed for possible discrepancies between trial and review reports, and omissions of relevant trials and data. Alternative data from discrepancies and omissions were then imputed in a sensitivity analysis, to test if review conclusions were robust.Only clinicians who had performed LLLT trials with negative results were invited into the review group. Review quality was sound in areas of literature search and methodological assessments, and some of the limitations were mentioned. The statistical analysis held 18 questionable selections such as omissions of trials, data, and subgroup analyses. These selections systematically favored the negative review conclusion. Without altering the review protocol, the sensitivity analysis of combined results changed to significantly positive for continuous and categorical data when data from all included trials were combined. Further sensitivity analyses with inclusion of valid non-included trials, performance of missing follow-up, and subgroup analyses revealed consistent and highly significant results in favor of active LLLT.In this example, the Cochrane review conclusion was neither robust nor valid. Representation of experts and different views on efficacy in the review group and extensive use of sensitivity analyses could probably improve quality control of reviews in areas of controversy.

Our aim was to investigate the effect of low-level laser therapy (LLLT), 650-nm wavelength, on acute inflammatory pleurisy.There is only scattered evidence of anti-inflammatory effects from LLLT and dosage characteristics, and the effect on pleurisy inflammation has yet to be investigated.A classical experimental model of pleurisy was used in a sample of 40 Balb male mice, randomly divided into five groups. Inflammation was induced by carrageenan (0.5 mg/cavity) administered by intrathoracic injections. Four groups received the inflammatory agent, and one received injections of sterile saline solution. At 1, 2, and 3 h after injections, LLLT irradiation was performed, with the same power (2.5 mW), but different irradiation times. The energy densities at each of the three treatment sessions were 0 J/cm(2) (placebo), 3 J/cm(2), 7.5 J/cm(2), and 15 J/cm(2), respectively.Total and differential cell analysis at 4 h after induction of pleurisy showed a significant reduction of inflammatory cell migration for all groups treated with active laser. However, at 4 h after injection, the most significant (p0.001) reduction of leukocyte cell migration was seen in the 7.5 J/cm(2) group, at 2.7 (95% CI: 2.5-2.9) x 10(6), versus 7.9 (95% CI: 6.7-9.1) x 10(6) in the placebo control group. The greatest reduction of inflammatory cells was registered for neutrophils.LLLT administered at 1-3 h after the induction of inflammatory pleurisy significantly reduces the inflammatory cell migration measured. Under these conditions and at 2.5 mW, 7.5 J/cm(2) was more effective than 3 J/cm(2) and 15 J/cm(2).

Some conclusions from the Cochrane Database of Systematic Reviews (CDSR) seem volatile in areas of controversy and have recently changed conclusions. With this perspective in mind we decided to test the validity and sensitivity of negative conclusions in a systematic review of low-level laser therapy (LLLT) for osteoarthritis (OA) from the Cochrane Library was valid and robust.None as this was a systematic review of literature.Validity was tested against a 9-item checklist for systematic reviews. Review selections were analyzed for possible discrepancies between trial and review reports and omissions of relevant trials and data. Data from discrepancies and omissions were then entered into sensitivity and subgroup analyses.Continuous and dichotomous data for painPatients with osteoarthritis.LLLT.Only clinicians who had performed LLLT trials, and had negative results were invited into the review group. The review was oblivious to findings published after 1993 about physiologic mechanisms and dose response patterns for LLLT. We found 18 questionable selections that favored a negative review conclusion in 17 of 18 cases. These were largely omissions of relevant positive data and selective inclusion of negative data from trials with small, ineffective doses. When existing and omitted data from relevant trials were combined, results changed from negative to significantly positive for continuous and categorical data. Subgrouping trials by location and recommended doses taken from current guidelines, revealed a highly significant effect of LLLT for treating knee OA.The results of this CDSR was not robust and seems to be colored by questionable selections or omissions. For alternative pain therapies, it should be considered if lack of expertise on therapy mechanisms, or conflicts of interests with competing pain drug manufacturers, may bias conclusions. Review groups should recruit a balanced mix of current views and expertise and expand the use of sensitivity analyses to improve quality of CDSRs in areas of controversy.