Effect of physical training on the adipose tissue of diet-induced obesity mice: interaction between reactive oxygen species and lipolysis.

It is well known that high-fat diets (HFDs) induce obesity and result in an increase in oxidative stress in adipose tissue, which leads to an impairment of fat mobilization by a downregulation of the lipases, such as hormone-sensitive lipase (HSL) and adipose triglyceride lipase (ATGL). On the other hand, exercise training leads to a reduction in adipose tissue and an improvement of antioxidant status and the lipolytic pathway. Our aim was to examine the influence of exercise and moderate intensity training on oxidative stress parameters and the relationship between the proteins involved in the lipolysis of animals subjected to a high-fat fed diet. Twenty-four mice were used and divided into 4 groups (n=6): standard diet (SD); standard diet plus exercise (SD+Ex); high-fat diet (HFD); and high-fat diet plus exercise (HFD+Ex). The animals received HFD for 90 days and submitted to a daily training protocol in swinging. The animals were euthanized 48 h after the last session of exercise. White adipose tissue epididymal fat was excised for the measurement of oxidative stress parameters and protein levels of lipolytic enzymes by Western blotting. The results show an increase in body weight after 90 days of HFD, and exercise training prevented great gain. In adipose tissue, lipid peroxidation and protein carbonylation increased after HFD and decreased significantly after exercise training. The protein level of CGI-58 was reduced, and FAS was increased in the HFD than in SD, whereas ATGL exhibited an increase (p<0.05) in HFD than in SD. The exercise plays a significant role in reducing oxidative damage, along with the regulation of proteins that are involved in the lipolysis of animals exposed to HFD.

Physical training prevents depressive symptoms and a decrease in brain-derived neurotrophic factor in Parkinson's disease.

Depression is a neuropsychiatric disorder that is commonly found in patients with Parkinson's disease (PD). Many studies have suggested that physical exercise can have an antidepressant effect by increasing the levels of brain-derived neurotrophic factor (BDNF), and may also prevent neurodegenerative disease. However, different forms of training may promote different changes in the brain. The aim of this study was to investigate the effects of two types of physical training on depressive-like behavior, and on the levels of proBDNF, BDNF, and its receptor, TrkB, in a mouse model of PD. C57BL/6 mice were subjected to 60 days of exercise: either running on a treadmill or performing a strength exercise. PD was induced by striatal administration of 6-OHDA 24h after the last physical exercise session. Seven days after 6-OHDA injection, depressive-like behavior and apomorphine-induced rotational behavior were evaluated. The levels of proBDNF, BDNF, and TRKB were measured in the striatum and the hippocampus of mice by immunoblotting assay. The 6-OHDA-treated animals showed a significant increase in immobility time and rotational behavior compared with the control group. In addition, significant decreases in the levels of proBDNF, BDNF, and its receptor, TrkB were observed in the 6-OHDA group. Both types of physical exercise prevented depressive-like behavior and restored the levels of proBDNF, BDNF, and TrkB in the striatum and hippocampus of mice administered 6-OHDA. Our results demonstrate that exercise training was effective for neuroprotection in the striatum and the hippocampus in an experimental model of PD.

Effect of eccentric training on mitochondrial function and oxidative stress in the skeletal muscle of rats.

The objective of the present study was to investigate the effects of eccentric training on the activity of mitochondrial respiratory chain enzymes, oxidative stress, muscle damage, and inflammation of skeletal muscle. Eighteen male mice (CF1) weighing 30-35 g were randomly divided into 3 groups (N = 6): untrained, trained eccentric running (16°; TER), and trained running (0°) (TR), and were submitted to an 8-week training program. TER increased muscle oxidative capacity (succinate dehydrogenase and complexes I and II) in a manner similar to TR, and TER did not decrease oxidative damage (xylenol and creatine phosphate) but increased antioxidant enzyme activity (superoxide dismutase and catalase) similar to TR. Muscle damage (creatine kinase) and inflammation (myeloperoxidase) were not reduced by TER. In conclusion, we suggest that TER improves mitochondrial function but does not reduce oxidative stress, muscle damage, or inflammation induced by eccentric contractions.

Physical training exerts neuroprotective effects in the regulation of neurochemical factors in an animal model of Parkinson's disease.

The effect of physical training on the neurochemical and oxidative stress markers were evaluated in the striatum of rats with Parkinson's disease (PD). Untrained+sham-operated (USO), untrained+PD (UPD), trained+sham-operated (TSO), and trained+PD (TPD) were submitted to training on the treadmill. The PD was induced and 7 days after the lesion, the animals underwent a rotational test and euthanasia by decapitation. The striatum was homogenized for Western Blot with anti-tyrosine hydroxylase (TH), anti-brain-derived neurotrophic factor (BDNF), anti-α-synuclein, anti-sarcoplasmic reticulum Ca(2+)-ATPase (SERCA II), anti-superoxide dismutase (SOD), anti-catalase (CAT), anti-glutathione peroxidase (GPX), and specific buffer for oxidative damage (TBARS and carbonyl content). The UPD and TPD groups showed a clear rotational asymmetry, apart from a significant reduction in the level of TH, BDNF, α-synuclein, SOD, CAT, and GPX as well as an increase in the TBARS and carbonyl content, as observed in the UPD group. The TH level was not significantly altered but the TPD group increased the levels of BNDF, SERCA II, SOD, and CAT and decreased the oxidative damage in lipids and protein. The effects of exercise on PD indicate the possibility that exercise, to a certain extent, modulates neurochemical status in the striatum of rats, possibly by improving the oxidative stress parameters.

Effect of eccentric training on mitochondrial function and oxidative stress in the skeletal muscle of rats

The objective of the present study was to investigate the effects of eccentric training on the activity of mitochondrial respiratory chain enzymes, oxidative stress, muscle damage, and inflammation of skeletal muscle. Eighteen male mice (CF1) weighing 30-35 g were randomly divided into 3 groups (N = 6): untrained, trained eccentric running (16°; TER), and trained running (0°) (TR), and were submitted to an 8-week training program. TER increased muscle oxidative capacity (succinate dehydrogenase and complexes I and II) in a manner similar to TR, and TER did not decrease oxidative damage (xylenol and creatine phosphate) but increased antioxidant enzyme activity (superoxide dismutase and catalase) similar to TR. Muscle damage (creatine kinase) and inflammation (myeloperoxidase) were not reduced by TER. In conclusion, we suggest that TER improves mitochondrial function but does not reduce oxidative stress, muscle damage, or inflammation induced by eccentric contractions.

Efeitos da laserterapia de baixa potência na reposta oxidativa epidérmica induzida pela cicatrização de feridas / Effects of low-level laser therapy on epidermal oxidative response induced by wound healing

INTRODUÇÃO: O uso terapêutico do laser de baixa potência na fisioterapia tem aumentado significativamente. OBJETIVO: Avaliar os efeitos da laserterapia de baixa potência nos parâmetros oxidativos na cicatrização de feridas em ratos. MÉTODOS: Dezoito ratos Wistar foram divididos randomicamente em 3 grupos (controle 5 dias, n=6; 5 dias/2 J/cm², n=6; 5 dias/4 J/cm², n=6). Uma única ferida circular medindo 8 X 8 mm foi cirurgicamente realizada no dorso do rato. Trinta minutos após a última irradiação, os ratos foram submetidos à eutanásia, e o tecido irradiado foi removido cirurgicamente e armazenado a -70ºC. Foi determinada a atividade das enzimas da cadeia respiratória: DCIP oxirredutase (complexo II) e succinato desidrogenase solúvel (SDH), atividade do citocromo c oxidase (complexo IV), produção de ânion superóxido, atividade da superóxido dismutase (SOD) e catalase (CAT). A lipoperoxidação foi avaliada pela técnica de TBARS. RESULTADOS: Os resultados mostram uma diminuição na atividade do complexo II nos grupos irradiados por 5 dias com 2 e 4 J/cm², enquanto a produção de ânion superóxido mostrou uma diminuição significativa no grupo irradiado por 5 dias com 4 J/cm² em relação ao grupo controle. Além disso, um aumento significativo na atividade da catalase foi observado no grupo irradiado por 5 dias com 2 J/cm², como também uma diminuição da peroxidação lipídica nos dois grupos irradiados. CONCLUSÕES: Os resultados do presente estudo indicam que o laser estimula a atividade antioxidante e protege a célula contra danos oxidativos durante o processo de cicatrização de feridas cutâneas em ratos.

BACKGROUND: Therapeutic use of low-level laser in physical therapy has increased significantly. OBJECTIVE: To assess the effects of low-level laser therapy on the oxidative parameters of wound healing in rats. METHODS: Eighteen Wistar rats were randomly divided into three groups (control, 5 days, n=6; 2 J/cm², 5 days, n=6; 4 J/cm², 5 days, n=6). A single circular wound measuring 8 x 8 mm was surgically created on the rats' backs. Thirty minutes after the last irradiation, the rats were euthanized and the irradiated tissue was surgically removed and stored at -70°C. We determined the activity of the respiratory chain enzymes DCIP oxidoreductase (complex II) and soluble succinate dehydrogenase (SDH); the activity of cytochrome c oxidase (complex IV); the production of superoxide anion; and the activity of superoxide dismutase (SOD) and catalase (CAT). Lipid peroxidation was assessed by means of the TBARS assay. RESULTS: There was a decrease in the complex II activity in the groups irradiated for 5 days with 2 and 4 J/cm², while superoxide anion production decreased significantly in the group irradiated for 5 days with 4 J/cm² when compared with the control group. There was also a significant increase in CAT activity in the group irradiated for 5 days with 2 J/cm² as well as a decrease in lipid peroxidation activity in the two irradiated groups. CONCLUSIONS: The results of the present study indicate that laser stimulates antioxidant activity and protects cells against oxidative damage during the wound healing process in rats.