Effect of photobiomodulation in the balance between effector and regulatory T cells in an experimental model of COPD.

Introduction: Currently, Chronic Obstructive Pulmonary Disease (COPD) has a high impact on morbidity and mortality worldwide. The increase of CD4+, CD8+ cells expressing NF-κB, STAT4, IFN-γ and perforin are related to smoking habit, smoking history, airflow rate, obstruction and pulmonary emphysema. Furthermore, a deficiency in CD4+CD25+Foxp3+ regulatory T cells (Tregs) may impair the normal function of the immune system and lead to respiratory immune disease. On the other hand, the anti-inflammatory cytokine IL-10, produced by Treg cells and macrophages, inhibits the synthesis of several pro-inflammatory cytokines that are expressed in COPD. Therefore, immunotherapeutic strategies, such as Photobiomodulation (PBM), aim to regulate the levels of cytokines, chemokines and transcription factors in COPD. Consequently, the objective of this study was to evaluate CD4+STAT4 and CD4+CD25+Foxp3+ cells as well as the production of CD4+IFN- γ and CD4+CD25+IL-10 in the lung after PBM therapy in a COPD mice model. Methods: We induced COPD in C57BL/6 mice through an orotracheal application of cigarette smoke extract. PMB treatment was applied for the entire 7 weeks and Bronchoalveolar lavage (BAL) and lungs were collected to study production of IFN- γ and IL-10 in the lung. After the last administration with cigarette smoke extract (end of 7 weeks), 24 h later, the animals were euthanized. One-way ANOVA followed by NewmanKeuls test were used for statistical analysis with significance levels adjusted to 5% (p < 0.05). Results: This result showed that PBM improves COPD symptomatology, reducing the number of inflammatory cells (macrophages, neutrophils and lymphocytes), the levels of IFN-γ among others, and increased IL-10. We also observed a decrease of collagen, mucus, bronchoconstriction index, alveolar enlargement, CD4+, CD8+, CD4+STAT4+, and CD4+IFN-γ+ cells. In addition, in the treated group, we found an increase in CD4+CD25+Foxp3+ and CD4+IL-10+ T cells. Conclusion: This study suggests that PBM treatment could be applied as an immunotherapeutic strategy for COPD.

Photobiomodulation mitigates Bothrops jararacussu venom-induced damage in myoblast cells by enhancing myogenic factors and reducing cytokine production.

BACKGROUND: Photobiomodulation has exhibited promise in mitigating the local effects induced by Bothrops snakebite envenoming; however, the mechanisms underlying this protection are not yet fully understood. Herein, the effectiveness of photobiomodulation effects on regenerative response of C2C12 myoblast cells following exposure to Bothrops jararacussu venom (BjsuV), as well as the mechanisms involved was investigated. METHODOLOGY/PRINCIPAL FINDINGS: C2C12 myoblast cells were exposed to BjsuV (12.5 µg/mL) and irradiated once for 10 seconds with laser light of 660 nm (14.08 mW; 0.04 cm2; 352 mW/cm2) or 780 nm (17.6 mW; 0.04 cm2; 440 mW/ cm2) to provide energy densities of 3.52 and 4.4 J/cm2, and total energies of 0.1408 and 0.176 J, respectively. Cell migration was assessed through a wound-healing assay. The expression of MAPK p38-α, NF-Кß, Myf5, Pax-7, MyoD, and myogenin proteins were assessed by western blotting analysis. In addition, interleukin IL1-ß, IL-6, TNF-alfa and IL-10 levels were measured in the supernatant by ELISA. The PBM applied to C2C12 cells exposed to BjsuV promoted cell migration, increase the expression of myogenic factors (Pax7, MyF5, MyoD and myogenin), reduced the levels of proinflammatory cytokines, IL1-ß, IL-6, TNF-alfa, and increased the levels of anti-inflammatory cytokine IL-10. In addition, PBM downregulates the expression of NF-kB, and had no effect on p38 MAKP. CONCLUSION/SIGNIFICANCE: These data demonstrated that protection of the muscle cell by PBM seems to be related to the increase of myogenic factors as well as the modulation of inflammatory mediators. PBM therapy may offer a new therapeutic strategy to address the local effects of snakebite envenoming by promoting muscle regeneration and reducing the inflammatory process.

Photobiomodulation in promoting increased Skin Flap Viability: a systematic review of animal studies.

Necrosis is common in skin flap surgeries. Photobiomodulation, a noninvasive and effective technique, holds the potential to enhance microcirculation and neovascularization. As such, it has emerged as a viable approach for mitigating the occurrence of skin flap necrosis. The aim of this systematic review was to examine the scientific literature considering the use of photobiomodulation to increase skin-flap viability. The preferred reporting items for systematic reviews and meta-analyses (PRISMA), was used to conducted systematic literature search in the databases PubMed, SCOPUS, Elsevier and, Scielo on June 2023. Included studies investigated skin-flap necrosis employing PBMT irradiation as a treatment and, at least one quantitative measure of skin-flap necrosis in any animal model. Twenty-five studies were selected from 54 original articles that addressed PBMT with low-level laser (LLL) or light-emitting diode (LED) in agreement with the qualifying requirements. Laser parameters varied markedly across studies. In the selected studies, the low-level laser in the visible red spectrum was the most frequently utilized PBMT, although the LED PBMT showed a similar improvement in skin-flap necrosis. Ninety percent of the studies assessing the outcomes of the effects of PBMT reported smaller areas of necrosis in skin flap. Studies have consistently demonstrated the ability of PBMT to improve skin flap viability in animal models. Evidence suggests that PBMT, through enhancing angiogenesis, vascular density, mast cells, and VEGF, is an effective therapy for decrease necrotic tissue in skin flap surgery.

Photobiomodulation therapy on local effects induced by juvenile and adult venoms of Bothrops alternatus.

Bothrops snake envenomation is characterized by severe local manifestations such as pain, edema, inflammation, hemorrhage, and myonecrosis. Furthermore, it is described that venom from juvenile and adult snakes may have differences in their composition that can lead to differences in the evolution of the clinical manifestation of the victim. Photobiomodulation (PBM) has been shown to be an effective adjuvant therapy to serum therapy to reduce the local effects induced by bothropic snake venom. This study evaluated the effect of PBM on the local reaction, after Bothrops alternatus snake venom (BaV) injection, in its juvenile (BaJV) and adult (BaAV) stages. Balb/C mice were injected with the juvenile or adult venoms of BaV or saline solution (control group). PBM at a wavelength of 660 nm, 100 mW, 0.33 W/cm2, 40 s, and a 0.028 cm2 beam was applied transcutaneous to a single point with a radiant exposure of 4 J/cm2, 30 min after venom injection. Edema, inflammatory infiltrate, hyperalgesia, and myonecrosis were analyzed. Both venoms induced significant edema and myonecrosis in the gastrocnemius muscle. Hyperalgesia in the mice paw and a prominent leukocyte infiltrate into the peritoneum were also observed. PBM significantly reduced all evaluated parameters. In conclusion, PBM treatment was effective in reducing the local effects induced by B. alternatus venom at different stages of snake development and could be a useful tool as an adjuvant treatment for bothropic envenomation.

Analysis of the Potential of Blood Transvascular Sublingual with Light-Emitting Diode Irradiation in COVID-19 Patients: A Pilot Clinical Study.

Background: Due to the high morbidity and mortality rates of this century, the COVID-19 pandemic has had a devastating impact on the health of the global population. Objective: The aim was to evaluate the disturbing impact of in-hospital stay length and the appeal of severe problems for supplemental oxygen for our patients with COVID-19 in moderate stage who were undergoing transvascular blood irradiation onto sublingual vessels. The demand for supplemental oxygen and the serum oxygen levels were measured, and the impact on the length of hospital stay was assessed. Methods: This randomized, prospective, clinical pilot study evaluated the diagnosis of COVID-19 patients admitted to the ventilatory care unit and undergoing treatment protocol usage of light-emitting diode (LED) irradiation by transvascular application onto the sublingual vessels daily. Patients were selected and enrolled into two groups: the Placebo group (n = 7) that received conventional treatment by the device off (LED-off), and the photobiomodulation therapy (PBMT) group (n = 7) that also received the same therapy plus LED irradiation. Results: There was a statistically significant clinical improvement, such as a reduction in serum creatinine, and oxygen usage per few days less in the PBMT group compared with the Placebo group. All patients in the PBMT group had normalized SatO2, while a quarter of patients in the Placebo group required longer O2 supplementation until hospital discharge. Conclusions: The surveillance of clinical improvement in moderate stage indicated that the daily PBMT was able to diminish oxygen supplementation within a short time, besides reducing the hospital stay length in the PBMT group, particularly, when compared with the Placebo group. Clinical Trial Registration number: The study was reviewed by the Ethics Committee in UNINOVE research under number 42325020.6.0000.5511 and approved through number 5,090,119.

Local envenomation caused by a bioactive peptide fraction of Bothrops jararaca snake venom induces leukocyte influx in the lung and changes in pulmonary mechanics.

The crude venom of the Bothrops jararaca snake (Bj-CV) is a complex mixture of biologically active proteins that includes a variety of peptides in the low molecular weight fraction (Bj-PF). We investigated how an intramuscular injection of Bj-CV (1.2 mg kg-1) and Bj-PF (0.24 mg kg-1) influenced lung mechanics and lung and muscle inflammation in male Swiss mice 15 min, 1, 6, and 24 h after inoculation. Pressure dissipation against lung resistive components (ΔP1) rose significantly from 1 to 24 h after Bj-CV and 6-24 h after Bj-PF inoculation. Both Bj-CV and Bj-PF increased the total pressure variation of the lung (ΔPtot) 24 h after injection. Lung static elastance increased significantly after injection in all time periods investigated by Bj-CV and from 6 to 24 h by Bj-PF. Lung static elastance increased significantly after injection in all time periods investigated by Bj-CV and from 6 to 24 h by Bj-PF. Furthermore, intramuscular inoculation of Bj-CV and Bj-PF resulted in an increase in muscle and pulmonary inflammation, as evidenced by an increase in leukocyte influx when compared to the control group. Finally, both Bj-CV and Bj-PF cause acute lung injury, as shown by pulmonary inflammation and decreased lung mechanics. Furthermore, the fact that Bj-PF produces mechanical alterations in the lungs and muscular inflammation implies that non-enzymatic compounds can cause inflammation.

Efeito da fotobiomodulação na modulação da interleucina-10: revisão narrativa de estudos clínicos / Effect of photobiomodulation on interleukin-10 modulation: narrative review of clinical studies

O sistema imune envolve diversos mecanismos de resposta imunológica que são fundamentais para o organismo se manter em equilíbrio e protegido. Dentre estes mecanismos, há a expressão de citocinas anti-inflamatórias e imunomoduladoras, como a interleucina-10 (IL-10). Esta citocina anti-inflamatória tem um papel crucial no sistema imune, uma vez que desempenha inúmeras funções biológicas. Estudos têm demonstrado que a terapia de fotobiomodulação (TFBM) tem sido eficaz na modulação da citocina IL-10, aumentando sua expressão, em várias doenças de caráter inflamatório. Apesar do mecanismo de ação da TFBM ainda não ser totalmente compreendido, esta vem se mostrando uma terapia promissora para estas doenças. Diante disso, o objetivo deste trabalho foi revisar estudos clínicos em que avaliaram a liberação/expressão da citocina IL-10 em diversas patologias em resposta à TFBM, e discutir as evidências atuais e potenciais da fotobiomodulação.

The immune system involves several immune response mechanisms that are essential for the body to remain in balance and protected. Among these mechanisms, there is the expression of anti-inflammatory and immunomodulatory cytokines, such as interleukin-10 (IL-10). This anti-inflammatory cytokine plays a crucial role in the immune system, since it performs numerous biological functions. Studies have shown that photobiomodulation therapy (PBMT) has been effective in modulating the cytokine IL-10, increasing its expression, in various diseases of an inflammatory character. Although the mechanism of action of PBMT is not yet fully understood, it has been shown to be a promising therapy for these diseases. Therefore, the objective of this work was to review clinical studies in which they evaluated the release / expression of the cytokine IL-10 in several pathologies in response to PBMT, and to discuss the current and potential evidences of photobiomodulation.

Light emitting diode (LED) photobiomodulation therapy on murine macrophage exposed to Bothropstoxin-I and Bothropstoxin-II myotoxins.

The light-emitting diode (LED) is considered a therapeutic tool due to its anti-inflammatory, analgesic, and wound-healing effects, which occur through angiogenesis, decrease in IL-1ß and IL-6 secretion, and acceleration of the cicatricial process. Snakebites are an important public health problem in tropical regions of the world. LED treatment is a therapeutic tool associated with serum therapy used to minimize the local effects of snakebites, including decrease in creatine kinase (CK) and lactate dehydrogenase (LDH) concentrations, myonecrosis, and inflammatory and haemorrhagic responses. In this study, we analysed the photobiomodulation effect of LED on the activation of murine macrophages induced by BthTX-I or BthTX-II isolated from Bothrops jararacussu venom. Photobiomodulation caused an increase in mitochondrial metabolism and a considerable decrease in cytotoxicity in murine macrophages. Moreover, it induced a decrease in reactive oxygen species and nitrogen liberation. However, photobiomodulation caused an increase in macrophage phagocytic capacity and lipid droplet formation. The results of this study corroborated with those of others in an unprecedented way and provide a better understanding of the mechanism of action of photobiomodulation, besides offering a coadjuvant action treatment for the local effects of snakebites, not achieved with serum therapy alone.

Light emitting diode (LED) therapy reduces local pathological changes induced by Bothrops asper snake venom.

The therapeutic effect of the Light Emitting Diode (LED) treatment in two wavelengths (635 or 945 nm) was evaluated in the local pathological alterations induced by Bothrops asper snake venom. Mice received irradiation of infrared LED (120 mW, 945 nm) or red LED (110 mW, 635 nm) applied immediately, 1 and 2 h after venom injection. LED treatment reduced edema formation in the plantar region and gastrocnemius muscle and significantly reduced neutrophil migration and hyperalgesia after the venom injection. Also, both infrared LED and red LED treatment significantly reduced myonecrosis, as revealed by muscle CK and plasma CK levels. Histological analysis corroborated the reduction in the extent of venom-induced myonecrosis. In conclusion, our data demonstrates that PBM with LED light in both red and infrared wavelengths, when applied after envenomation in mice, reduces the extent of myotoxicity, edema, inflammatory infiltrate and hyperalgesia, suggesting that photobiomodulation is a potential therapeutic approach that should be further investigated for the treatment of local effects of Bothrops snakebite.

Photobiomodulation therapy on bothrops snake venom-induced local pathological effects: A systematic review.

Bothrops snakebite treatment is antivenom therapy, which is ineffective in neutralizing the severe local effects caused by these envenomations. There are evidence that photobiomodulation therapy (PBMT) has emerged as a promising tool to counteract the venom-induced local effects. The purpose was to write a narrative review of the literature about PBMT as a treatment for Bothrops snakebites. We reviewed articles indexed in PubMed, SCOPUS and Scientif Direct database with filter application. Included studies had to investigate local effects induced by Bothrops snake venom in any animal model using any type of photobiomodulation irradiation and at least one quantitative measure of local effects of Bothrops envenomation. Sixteen studies were selected from 54 original articles targeted PBMT (low-level laser or light emitting diode) as a complementary tool for local effects treatment induced by snakebites, and all its assessments. Articles were critically assessed by two independent raters with a structured tool for rating the research quality. PBMT demonstrate to be a promising tool for local treatment effects caused by snakebite by reducing local edema, hyperalgesia, leukocyte influx and myonecrosis and accelerating tissue regeneration related to myotoxicity. However, the mechanism is not well understood and additional studies are needed.

Analgesic Effect of Photobiomodulation on Bothrops Moojeni Venom-Induced Hyperalgesia: A Mechanism Dependent on Neuronal Inhibition, Cytokines and Kinin Receptors Modulation.

BACKGROUND: Envenoming induced by Bothrops snakebites is characterized by drastic local tissue damage that involves an intense inflammatory reaction and local hyperalgesia which are not neutralized by conventional antivenom treatment. Herein, the effectiveness of photobiomodulation to reduce inflammatory hyperalgesia induced by Bothrops moojeni venom (Bmv), as well as the mechanisms involved was investigated. METHODOLOGY/PRINCIPAL FINDINGS: Bmv (1 µg) was injected through the intraplantar route in the right hind paw of mice. Mechanical hyperalgesia and allodynia were evaluated by von Frey filaments at different time points after venom injection. Low level laser therapy (LLLT) was applied at the site of Bmv injection at wavelength of red 685 nm with energy density of 2.2 J/cm2 at 30 min and 3 h after venom inoculation. Neuronal activation in the dorsal horn spinal cord was determined by immunohistochemistry of Fos protein and the mRNA expression of IL-6, TNF-α, IL-10, B1 and B2 kinin receptors were evaluated by Real time-PCR 6 h after venom injection. Photobiomodulation reversed Bmv-induced mechanical hyperalgesia and allodynia and decreased Fos expression, induced by Bmv as well as the mRNA levels of IL-6, TNF-α and B1 and B2 kinin receptors. Finally, an increase on IL-10, was observed following LLLT. CONCLUSION/SIGNIFICANCE: These data demonstrate that LLLT interferes with mechanisms involved in nociception and hyperalgesia and modulates Bmv-induced nociceptive signal. The use of photobiomodulation in reducing local pain induced by Bothropic venoms should be considered as a novel therapeutic tool for the treatment of local symptoms induced after bothropic snakebites.

Human bronchial epithelial cells injury and cytokine production induced by Tityus serrulatus scorpion venom: An in vitro study.

Tityus serrulatus is the scorpion specie responsible for the majority of scorpion sting accidents in Brazil. Symptoms of envenomation by Tityus serrulatus range from local pain to severe systemic reactions such as cardiac dysfunction and pulmonary edema. Thus, this study has evaluated the participation of bronchial epithelial cells in the pulmonary effects of Tityus serrulatus scorpion venom (Tsv). Human bronchial epithelial cell line BEAS-2B were utilized as a model target and were incubated with Tsv (10 or 50 µg/mL) for 1, 3, 6 and 24 h. Effects on cellular response of venom-induce cytotoxicity were examined including cell viability, cell integrity, cell morphology, apoptosis/necrosis as well as cell activation through the release of pro-inflammatory cytokines IL-1ß, IL-6 and IL-8. Tsv caused a decrease in cell viability at 10 and 50 µg/mL, which was confirmed by lactate dehydrogenase (LDH) measurement. Flow cytometry analyses revealed necrosis as the main cell death pathway caused by Tsv. Furthermore, Tsv induced the release of IL-1ß, IL-6 and IL-8. Altogether, these results demonstrate that Tsv induces cytotoxic effects on bronchial epithelial cells, involving necrosis and release of pro-inflammatory cytokines, suggesting that bronchial epithelial cells may play a role in the pulmonary injury caused by Tsv.

Effect of photobiomodulation on endothelial cell exposed to Bothrops jararaca venom.

Bleeding is a common feature in envenoming caused by Bothrops snake venom due to extensive damage to capillaries and venules, producing alterations in capillary endothelial cell morphology. It has been demonstrated, in vivo, that photobiomodulation (PBM) decreases hemorrhage after venom inoculation; however, the mechanism is unknown. Thus, the objective was to investigate the effects of PBM on a murine endothelial cell line (tEnd) exposed to Bothrops jararaca venom (BjV). Cells were exposed to BjV and irradiated once with either 660- or 780-nm wavelength laser light at energy densities of 4 and 5 J/cm(2), respectively, and irradiation time of 10 s. Cell integrity was analyzed by crystal violet and cell viability/mitochondrial metabolism by MTT assay. The release of lactic dehydrogenase (LDH) was quantified as a measure of cell damage. In addition, cytokine IL1-ß levels were measured in the supernatant. PBM at 660 and 780 nm wavelength was able to increase cellular viability and decrease the release of LDH and the loss of cellular integrity. In addition, the concentration of pro-inflammatory cytokine IL1-ß was reduced after PBM by both wavelengths. The data reported herein indicates that irradiation with red or near-infrared laser resulted in protection on endothelial cells after exposure to Bothrops venom and could be, at least in part, a reasonable explanation by the beneficial effects of PBM inhibiting the local effects induced by Bothrops venoms, in vivo.

Photobiomodulation Protects and Promotes Differentiation of C2C12 Myoblast Cells Exposed to Snake Venom.

BACKGROUND: Snakebites is a neglected disease and in Brazil is considered a serious health problem, with the majority of the snakebites caused by the genus Bothrops. Antivenom therapy and other first-aid treatments do not reverse local myonecrose which is the main sequel caused by the envenomation. Several studies have shown the effectiveness of low level laser (LLL) therapy in reducing local myonecrosis induced by Bothropic venoms, however the mechanism involved in this effect is unknown. In this in vitro study, we aimed to analyze the effect of LLL irradiation against cytotoxicity induced by Bothrops jararacussu venom on myoblast C2C12 cells. METHODOLOGY: C2C12 were utilized as a model target and were incubated with B. jararacussu venom (12.5 µg/mL) and immediately irradiated with LLL at wavelength of red 685 nm or infrared 830 nm with energy density of 2.0, 4.6 and 7.0 J/cm2. Effects of LLL on cellular responses of venom-induced cytotoxicity were examined, including cell viability, measurement of cell damage and intra and extracellular ATP levels, expression of myogenic regulatory factors, as well as cellular differentiation. RESULTS: In non-irradiated cells, the venom caused a decrease in cell viability and a massive release of LDH and CK levels indicating myonecrosis. Infrared and red laser at all energy densities were able to considerably decrease venom-induced cytotoxicity. Laser irradiation induced myoblasts to differentiate into myotubes and this effect was accompanied by up regulation of MyoD and specially myogenin. Moreover, LLL was able to reduce the extracellular while increased the intracellular ATP content after venom exposure. In addition, no difference in the intensity of cytotoxicity was shown by non-irradiated and irradiated venom. CONCLUSION: LLL irradiation caused a protective effect on C2C12 cells against the cytotoxicity caused by B. jararacussu venom and promotes differentiation of these cells by up regulation of myogenic factors. A modulatory effect of ATP synthesis may be suggested as a possible mechanism mediating cytoprotection observed under laser irradiation.

Photobiostimulation reduces edema formation induced in mice by Lys-49 phospholipases A2 isolated from Bothrops moojeni venom.

The prominent local myotoxic effects induced by Bothrops snake venom are due, in part, to myotoxins. This effect is not neutralized by antivenom, which is the main therapy for victims of snakebite. Two basic myotoxins named MjTX-I and MjTX-II were isolated from Bothrops moojeni venom. Both myotoxins have a Lys-49 phospholipase A2 structure devoid of enzymatic activity, but are highly myonecrotic and edema-inducing. In this study, we analyzed the effect of a low-level laser (LLL) at 685 nm, an energy density of 2.2 J cm(-2), and the irradiation time of 15 s, and a light emitting diode (LED) at 635 or 945 nm at energy densities of 4 and 3.8 J cm(-2), and irradiation times of 41 and 38 s, respectively, applied 30 min and 3 h after edema formation in mice caused by MjTX-I or MjTX-II. MjTX-I or MjTX-II caused a significant edema formation in envenomed paws. LLL and LED irradiation significantly reduced the edema formation by both myotoxins from 1 up to 6 hours after the injection. Both LLL and LEDs were similar in reducing the edema formation induced by myotoxins. The combined photobiostimulation with antivenom had the same effect in reducing edema as treatment with the LLL or LEDs alone. In conclusion, the results of this study indicate that photobiostimulation could be used in association with antivenom therapy for treatment of local effects of Bothrops species venom.

Protective effect of low-level laser therapy (LLLT) on acute zymosan-induced arthritis.

The aim of this study was to evaluate the effect of low-level laser therapy on acute zymosan-induced arthritis, with respect to the laser action on inflammatory cells influx, release of pro-inflammatory mediators, metalloproteinases activity into the joint cavity and the cartilage repair process. Arthritis was induced in male Wistar rats (250-280 g) by intra-articular injection of zymosan (1 mg dissolved in 50 µl of a sterile saline solution) into one rear knee joint. Animals were irradiated immediately, 1 and 2 h after zymosan administration with a semiconductor laser InGaAIP (660 nm, 10 mW, 2.5 J/cm(2), 10 s). In the positive control group, animals were injected with the anti-inflammatory drug dexamethasone 1 h prior to the zymosan administration. Treatment with laser significantly inhibited leukocytes influx, the release of IL-1 and IL-6 and also the activity of metalloproteinase-2 and 9, into the joint cavity. In conclusion, laser therapy was effective in reducing inflammation to sites of injury and inhibit activation of proteases (gelatinase) suggesting less degradation of collagen tissue in experimental model of acute arthritis.

Efeito da terapia LED (Light Emitting Diode) na mionecrose e edema induzidos pelo veneno a serpente Bothrops jararaca, no músculo gastrocnêmio / Effect of LED (Light Emission Diode) therapy on edema formation and myonecrosis induced by Bothrops jararaca snake venom, on gatrocnemius muscle

Introdução: O envenenamento causado pela serpente Bothrops jararaca induz, de modo geral, um quadro fisiopatológico caracterizado por reações locais imediatas, com hemorragia, mionecrose, edema e dor, que não é revertido pelo tratamento com o antiveneno. Objetivo: Neste trabalho avaliou-se a capacidade da terapia LED (Light EmitionDiode) para diminuir o edema e a mionecrose causada pelo veneno de B. jararaca. Método: Foram utilizados camundongos wiss machos injetados com veneno de B. jararaca (2 mg/kg) no músculo gastrocnêmio. O edema foi avaliado nos tempos 3 e 24 h após a injeção do veneno ou salina. O aumento do edema foi expresso como a diferença do volume do peso úmido e peso seco, dos músculos tratados com o veneno, comparado com o volume do músculo contralateral (controle). A mionecrose foi avaliada através da quantificação da enzima creatino quinase no tempo de 3 h e da análise histológica dos músculos 3 e 24 h após a injeção do veneno. Os animais foram tratados com os LEDs (LED infravermelho, potência de 120 mW, À 945 nm, densidade de energia de 4 J/cm2, tempo de irradiação de 38 s e área of 1,2 cm2; LED vermelho potência de 110 mW, À 635 nm, densidade de energia de 4 J/cm2, tempo de irradiação de 41 s e área de 1,2 cm2) nos tempos: imediatamente e 2 horas após a injeção do veneno. Resultados: O edema muscular causado pelo veneno de B. jararaca foi significativamente reduzido pelos dois tratamentos utilizados: LED vermelho 20 e 11% e LED infravermelho: 29 e 19%, às 3 e 24 h respectivamente, quando comparado com os animais tratados com o veneno. O tratamento com o LED não modificou a mionecrose causada pelo veneno. Conclusões: A terapia LED foi eficaz em reduzir o edema muscular, no entanto, a mionecrose não foi afetada pelo tratamento com os LEDs. Desta maneira, a terapia com o LED pode contribuir, ao menos em parte, como uma alternativa ao tratamento atual, adicionado a terapia disponível com antivenenos, não efetiva contra os efeitos locais.

Introduction: Envenoming caused by Bothrops jararaca venom induces, in general, a physiopatologic reaction characterized by immediate local reactions, with hemorrhage, mionecrosis, edema and pain, which are not reverted by thetreatment with antivenenom. Objetive: In this work, it was evaluated the capacity of LED (Light Emition Diode) therapy to diminish the edema formation and mionecrosis, caused by Bothrops jararaca venom. Methods: Swiss mice had been injected with B. jararaca venom (2 mg/kg) in the gastrocnemius muscle. Edema was evaluated at 3 and 24 after the injection of the venom or saline. The increase on edema formation was expressed as the difference betweethe humid and dry weight, of the muscles injected with the poison, compared with the volume of the contralateral muscle (control). Mionecrosis was evaluated through the quantification of the creatine kinase enzyme at 3 h and by histologic analysis of the muscle, 3 and 24 h after the injection of the venom. The animais had been treated with the LE(infra-red: power of 120 mW, li 945 nm, density of energy of 4 J/cm2, time of irradiation of 38 s and area of 1,2 cm2; Red LED: power of 110 mW, li 635 nm, density of energy of 4 J/cm 2, time of irradiation of 41 s and area of 1,2 cm 2) applied: immediately and 2 h after the venom injection. Results: Muscular edema caused by the B. jararaca venom was significantly reduced by the two treatments: Red LED: 20 and 11% and infrared LED: 29 and 19%, to 3 and 24 t;respectively, when compared with the animais treated with venom. The treatment with the LED did not modify the mionecrosis caused by the venom. Conclusion: LED therapy was efficient in reducing muscular edema, however, mionecrosis was not affected by these treatment. In this way, the LED therapy can contribute, at least in part, as an alternative added to the available therapy with antivenoms, which are not effective against the local effect.

Anti-inflammatory effect of low-level laser and light-emitting diode in zymosan-induced arthritis.

OBJECTIVE: The aim of this work was to investigate the effect of low-level laser therapy (LLLT) and light-emitting diode (LED) on formation of edema, increase in vascular permeability, and articular joint hyperalgesia in zymosan-induced arthritis. BACKGROUND DATA: It has been suggested that low-level laser and LED irradiation can modulate inflammatory processes. MATERIAL AND METHODS: Arthritis was induced in male Wistar rats (250-280 g) by intra-articular injection of zymosan (1 mg in 50 microL of a sterile saline solution) into one rear knee joint. Animals were irradiated immediately, 1 h, and 2 h after zymosan administration with a semiconductor laser (685 nm and 830 nm) and an LED at 628 nm, with the same dose (2.5 J/cm(2)) for laser and LED. In the positive control group, animals were injected with the anti-inflammatory drug dexamethasone 1 h prior to the zymosan administration. Edema was measured by the wet/dry weight difference of the articular tissue, the increase in vascular permeability was assessed by the extravasation of Evans blue dye, and joint hyperalgesia was measured using the rat knee-joint articular incapacitation test. RESULTS: Irradiation with 685 nm and 830 nm laser wavelengths significantly inhibited edema formation, vascular permeability, and hyperalgesia. Laser irradiation, averaged over the two wavelengths, reduced the vascular permeability by 24%, edema formation by 23%, and articular incapacitation by 59%. Treatment with LED (628 nm), with the same fluence as the laser, had no effect in zymosan-induced arthritis. CONCLUSION: LLLT reduces inflammatory signs more effectively than LED irradiation with similar irradiation times (100 sec), average outputs (20 mW), and energy doses (2 J) in an animal model of zymosan-induced arthritis. The anti-inflammatory effects of LLLT appear to be a class effect, which is not wavelength specific in the red and infrared parts of the optical spectrum.

Effect of low-level laser therapy in the myonecrosis induced by Bothrops jararacussu snake venom.

OBJECTIVE: The aim of this work was to investigate the capacity of low-level laser therapy (LLLT) alone or in combination with antivenom (AV) to reduce myonecrosis induced by Bothrops jararacussu snake venom. BACKGROUND DATA: Myonecrosis is the most pronounced local effect caused by B. jararacussu venom. AV therapy and other first-aid treatments do not reverse these local effects. MATERIAL AND METHODS: Male Swiss mice were used. Myonecrosis was induced by injection of 0.6 mg/kg of B. jararacussu venom in the right gastrocnemius muscle and was evaluated at 3 or 24 h after venom injection. The site of venom administration was irradiated for 29 s with a low power semiconductor laser (685 nm) at a dose of 4.2 J/cm(2). Intravenous AV therapy (0.5 mL dose) was administered at different times: 30 min before venom injection or 0, 1, or 3 h afterward. Both AV therapy and LLLT treatments were duplicated in mice groups killed at 3 or 24 h. RESULTS: B. jararacussu venom caused a significant myonecrotic effect 3 and 24 h after venom injection. LLLT significantly reduced myonecrosis by 83.5% at 24 h (p < 0.05) but not at 3 h, and AV therapy alone was ineffective for reducing myonecrosis at 3 and 24 h. CONCLUSION: Only LLLT significantly reduced myonecrosis of the envenomed muscle, suggesting that LLLT is a potentially therapeutic approach for treating the local effects of B. jararacussu venom.