Laser Photobiomodulation in the acute inflammatory response of the calcaneal tendon injury in rats exposed to cigarette smoke

La nicotina retarda el proceso de cicatrización y eleva los niveles de la enzima mieloperoxidasa (MPO), que tiene un papel fundamental en la producción de especies reactivas de oxígeno durante el proceso inflamatorio. La fotobiomodulación con láser (FBM) es uno de los agentes electrofísicos más utilizados en el tratamiento del tendón calcáneo, sin embargo sus efectos sobre la actividad de la MPO carecen de mayor elucidación. Este estudio objetivó evaluar los efectos de la FBM sobre la actividad de la MPO después de lesión del tendón calcáneo en ratones expuestos al humo de cigarrillo. Se utilizaron 34 ratones Wistar, machos, con 90 días de vida. Después de 14 días de exposición al humo de cigarrillo, los animales fueron divididos en tres grupos experimentales: grupo de control (GC, n=12), no sometido a la lesión o tratamiento; grupo sham (GSh, n=10), sometido a la lesión parcial del tendón calcáneo y a la simulación de la FBM láser; y el grupo FBM láser (GFBM, n=12), sometido a la lesión parcial del tendón calcáneo y tratado con FBM láser, en el primer minuto después de la lesión. La FBM disminuyó los niveles de actividad de MPO en el GFBM en comparación con el GSh (GC: 1,38±0,69 pg/ml; GSh: 3,78±1,09pg/ml; GFBM: 2,58±0,93pg/ml, p<0,005). Se concluye que la FBM láser aplicada inmediatamente después de la lesión del tendón calcáneo atenúa la actividad inflamatoria aguda en ratones expuestos al humo de cigarrillo.A nicotina retarda o processo de cicatrização e eleva os níveis da enzima mieloperoxidase (MPO), a qual possui um papel fundamental na produção de espécies reativas de oxigênio durante o processo inflamatório. A fotobiomodulação laser (FBM) é um dos agentes eletrofísicos mais utilizados no tratamento do tendão calcâneo, no entanto, os seus efeitos sobre a atividade da MPO carecem de maior elucidação. Este estudo objetivou avaliar os efeitos da FBM sobre a atividade da MPO, após lesão do tendão calcâneo em ratos expostos à fumaça de cigarro. Foram utilizados 34 ratos Wistar, machos, com 90 dias de vida. Após 14 dias de exposição à fumaça de cigarro, os animais foram divididos em três grupos experimentais: grupo controle (GC, n=12), não submetido à lesão ou tratamento; grupo sham (GSh, n=10), submetido à lesão parcial do tendão calcâneo e a simulação da FBM laser; grupo FBM laser (GFBM, n=12), submetido à lesão parcial do tendão calcâneo e tratados com FBM laser, no primeiro minuto após a lesão. A FBM diminuiu os níveis de atividade da MPO no GFBM em comparação ao GSh (GC: 1,38±0,69 pg/ml; GSh: 3,78±1,09pg/ml; GFBM: 2,58±0,93pg/ml; p<0,005). Conclui-se que a FBM laser aplicada imediatamente após lesão do tendão calcâneo, atenua a atividade inflamatória aguda em ratos expostos à fumaça de cigarro.Nicotine delays the healing process and increases the levels of myeloperoxidase (MPO), an enzyme that plays a key role in the production of reactive oxygen species during the inflammatory process. Laser Photobiomodulation (PBM) is one of the most used electrophysical agents in the treatment of the calcaneal tendon, however, its effects on MPO activity need to be further elucidated. This study aimed to evaluate the effects of laser PBM on MPO activity after inflicting an injury to the calcaneal tendon of rats exposed to cigarette smoke. Thirty-four male Wistar rats with 90 days of age were used. After 14 days of exposure to cigarette smoke, the animals were divided into three experimental groups: control group (CG, n=12), not submitted to injury or treatment; sham group (ShG, n=10), submitted to partial calcaneal tendon injury and laser PBM simulation; and laser PBM group (PBMG, n=12), submitted to partial calcaneal tendon lesion and treated with laser PBM within the first minute after injury. PBM decreased MPO activity levels in PBMG compared to ShG (CG: 1.38±0.69pg/ml; ShG: 3.78±1.09pg/ml; PBMG: 2.58±0.93pg/ml; p<0.005). In conclusion, applying laser PBM immediately after inflicting damage to the calcaneal tendon attenuates acute inflammatory activity in rats exposed to cigarette smoke

<b>Trans-resveratrol reduces cardiac oxidative stress in rats exposed to cigarette smoke

Differences between reactive oxygen species and antioxidant defense system unbalance the redox status. The exposure to cigarette smoke can increase this imbalance. Trans-resveratrol is a polyphenol with great antioxidant action that reduces the oxidative stress. This study investigated the effect of the trans-resveratrol supplementation on the cardiac oxidative stress in rats exposed to cigarette smoke. Male Wistar rats were randomized into four groups: Control Group (CG), Exposure to Smoke Group (ESG), Antioxidant Group (AG) and Exposure to Smoke plus Antioxidant Group (ESAG). Animals were exposed to cigarette smoke and supplemented with trans-resveratrol (6.0 mg kg-1) for two months. The lipid peroxidation (TBARS) and the enzymatic activity of catalase (CAT) were measured in the cardiac muscle. The ESG presented the highest lipid peroxidation level compared with CG (p < 0.001), AG (p < 0.001) and ESAG (p < 0.006). The CAT activity was higher in the AG (p < 0.001) and ESAG (p < 0.001) compared with CG. The ESG presented lower CAT activity compared with the ESAG (p < 0.001). The supplementation of Trans-resveratrol attenuated the cardiac oxidative stress and increased the activity of catalase. Our findings evidenced the cardioprotective effect of trans-resveratrol in rats exposed to cigarette smoke