Ricardo A. Pinho

Imbalance in SOD/CAT activities in rat skeletal muscles submitted to treadmill training exercise

The association between physical exercise and oxidative damage in the skeletal musculature has been the focus of many studies in literature, but the balance between superoxide dismutase and catalase activities and its relation to oxidative damage is not well established. Thus, the aim of the present study was to investigate the association between regular treadmill physical exercise, oxidative damage and antioxidant defenses in skeletal muscle of rats. Fifteen male Wistar rats (8–12 months) were randomly separated into two groups (trained n = 9 and untrained n = 6). Trained rats were treadmill‐trained for 12 weeks in progressive exercise (velocity, time, and inclination). Training program consisted in a progressive exercise (10 m/min without inclination for 10 min/day). After 1 week the speed, time and inclination were gradually increased until 17 m/min at 10% for 50 min/day. After the training period animals were killed, and gastrocnemius and quadriceps were surgically removed to the determination of biochemical parameters. Lipid peroxidation, protein oxidative damage, catalase, superoxide dismutase and citrate synthase activities, and muscular glycogen content were measured in the isolated muscles. We demonstrated that there is a different modulation of CAT and SOD in skeletal muscle in trained rats when compared to untrained rats (increased SOD/CAT ratio). TBARS levels were significantly decreased and, in contrast, a significant increase in protein carbonylation was observed. These results suggest a non‐described adaptation of skeletal muscle against exercise‐induced oxidative stress.

The effects of physical exercise on the cigarette smoke-induced pulmonary oxidative response

Studies have shown that the oxidative power of cigarettes is related to the pathogenesis of several pulmonary diseases and that regular physical exercise contributes significantly to reducing the deleterious effects of cigarettes. The objective of the present study was to investigate the therapeutic effects of physical exercise on histological and oxidative stress markers in animals exposed to cigarette smoke. Thirty-six male, eight-week-old C57BL-6 mice were divided into four groups (n = 9 for each group): control, exercise, cigarette smoke, and cigarette smoke plus exercise. The cigarette smoke (CS) groups were exposed to cigarette smoke 3 times/day (4 cigarettes/session) for 60 consecutive days. The exercise groups were submitted to swimming physical training 5 days/week for eight weeks. Forty-eight hours after the last exercise and cigarette exposure, the animals were sacrificed using cervical traction. The right lung was removed, processed, and stored for future analysis. In addition to the analysis of collagen content (hydroxyproline), oxidant production (anion superoxide), antioxidant enzyme activity (SOD and CAT), and lipid and protein oxidative damage (TBARS and Carbonylation), histological and morphological studies were performed. The results revealed that the animals exposed to cigarette smoke showed enlargement and destruction of the alveolar septum and increases in the numbers of macrophages and neutrophils, as well as in the amount of collagen. Our results also showed a decrease in the volume density of elastic fibers and an increase in the volume density of airspaces. However, physical exercise partially improved these markers. Additionally, physical exercise decreased oxidant production and increased the activity of the enzymatic antioxidant defense system, but did not reverse lipid and protein oxidative damage induced by cigarette smoke. These results suggest that physical training partially improves histological and oxidative stress parameters in the lungs of animals chronically exposed to cigarette smoke and that other therapies can contribute to potentiate these effects.

Short-term inhibition of SREBP-1c expression reverses diet-induced non-alcoholic fatty liver disease in mice.

Abstract Objective. The present study investigates the level of Sterol-regulatory element-binding proteins (SREBP-1c) and related proteins in obese mice (DIO) treated with SREBP-1c antisense oligonucleotide (ASO) to observe a reversal of steatosis. Materials and methods. Swiss mice were fed on chow containing 61 kJ% saturated fat for 8 weeks to develop obesity. After this period, one group of animals was used to assess the molecular effects of SREBP-1c antisense oligonucleotide treatment by immunoblot analysis in a dose-response curve (0; 1.0; 2.0; 3.0; 4.0 nmol/day). After the dose (3.0 nmol/day) was determined, another group was treated for 14 days. After a period of 24 h following the last injection mice were killed and plasma and hepatic tissue were obtained to evaluate plasma triglycerides and total liver fat. Western blot was performed to evaluate SREBP-1c, FAS, SCD-1, PPARγ and CPT1 expression and AMPK[Thr172] and ACC[Ser79] phosphorylation. Livers were stained using the hematoxylin and eosin method for histological analysis. Results. Body weight, epididymal fat and glucose levels were not affected by one daily dose of ASO. However, total plasma triglycerides and total liver fat were significantly reduced. Also, this treatment inhibited SREBP-1c and reduced protein levels of a series of proteins involved in lipogenesis, including ACC, FAS and SCD-1. Moreover, mice treated with ASO presented a significant reduction in macroscopic and microscopic features of hepatic steatosis. Conclusion. Our results demonstrate that the inhibition of SREBP-1c decreased the expression of lipogenic enzymes, reducing the accumulation of triglycerides and, finally, reversing hepatic steatosis in mice.

Effect of different models of physical exercise on oxidative stress markers in mouse liver

The aim of this study was to investigate the effect of different protocols of physical exercise on oxidative stress markers in mouse liver. Twenty-eight male CF1 mice (30-35 g) were distributed into 4 groups (n = 7) - untrained (UT), continuous running (CR), downhill running (D-HR), and intermittent running (IR) - and underwent an 8-week training program. Forty-eight hours after the last training session, the animals were killed, and their livers were removed. Blood lactate, creatine kinase, citrate synthase, thiobarbituric acid reactive species, carbonyl, superoxide dismutase (SOD), and catalase (CAT) activities were assayed. Results show a decrease in the level of lipoperoxidation and protein carbonylation in the CR and D-HR groups. SOD activity was significantly increased and CAT activity was reduced in the CR and D-HR groups. Our findings indicate that CR and D-HR may be important for decreasing oxidative damage and in the regulation of antioxidant enzymes (SOD and CAT) in the livers of trained mice.

Effects of moderate exercise on cigarette smoke exposure-induced hippocampal oxidative stress values and neurological behaviors in mice

The objective of the present study was to investigate the effects of exercise training on behavior and neurochemical parameters in mice exposed to cigarette smoke. To this aim, mice (C57 BL6) male (30-35 g) were exposed to cigarette smoke 60 consecutive days three times a day and they were subjected to treadmill training 8 weeks for 5 days/week. For behavior assessment, mice were tested in the open-field and forced to a swim test. The superoxide anion, thiobarbituric acid reactive substances and protein carbonyl formation were measured as markers of oxidative stress in hippocampus of mice. In addition, the brain-derived neurotrophic factor (BDNF) levels were measured in the hippocampus samples. Cigarette smoke group and cigarette smoke plus exercise group, increased immobility time in forced swimming test in rats compared to the control group, without affecting spontaneous locomotor activity. There was an increase in the levels of superoxide, TBARS and of protein carbonyl and a decreased in BDNF levels in the hippocampus of rats exposed to cigarette smoke and cigarette smoke plus exercise. Exercise alone did not change any of the parameters evaluated in this study. In conclusion, we observed that physical training improves the oxidative stress parameters, but does not alter depressive-like behavior neither prevent the decreases in BDNF levels in hippocampus induced by cigarette smoke.

Pulsed ultrasound associated with gold nanoparticle gel reduces oxidative stress parameters and expression of pro-inflammatory molecules in an animal model of muscle injury

BackgroundNanogold has been investigated in a wide variety of biomedical applications because of the anti-inflammatory properties. The purpose of this study was to evaluate the effects of TPU (Therapeutic Pulsed Ultrasound) with gold nanoparticles (GNP) on oxidative stress parameters and the expression of pro-inflammatory molecules after traumatic muscle injury.Materials and methodsAnimals were divided in nine groups: sham (uninjured muscle); muscle injury without treatment; muscle injury + DMSO; muscle injury + GNP; muscle injury + DMSO + GNP; muscle injury + TPU; muscle injury + TPU + DMSO; muscle injury + TPU + GNP; muscle injury + TPU + DMSO + GNP. The ROS production was determined by concentration of superoxide anion, modulation of antioxidant defenses was determined by the activity of superoxide dismutase, catalase and glutathione peroxidase enzymes, oxidative damage determined by formation of thiobarbituric acid-reactive substance and protein carbonyls. The levels of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) were measured as inflammatory parameters.ResultsCompared to muscle injury without treatment group, the muscle injury + TPU + DMSO + GNP gel group promoted a significant decrease in superoxide anion production and lipid peroxidation levels (p < 0.050). It also showed a significant decrease in TNF-α and IL-1β levels (p < 0.050) when compared to muscle injury without treatment group.ConclusionsOur results suggest that TPU + DMSO + GNP gel presents beneficial effects on the muscular healing process, inducing a reduction in the production of ROS and also the expression of pro-inflammatory molecules.

Oxidative Stress and Inflammatory Parameters After an Ironman Race

Objective: The aim of the present study was to investigate oxidative stress markers and inflammatory response in triathletes after an Ironman race (IR). Design: Descriptive research. Participants: Eighteen well-trained male triathletes (mean age, 34.7 ± 2.15 years; weight, 69.3 ± 1.9 kg; height, 1.81 ± 0.58 cm) participated in the study. Setting: Ironman Triathlon (3.8-km swim, 180-km cycle, 42.2-km run). Mean environmental conditions ranged from 20 to 25°C and from 79% to 85% relative humidity. Interventions: None. Main Outcome Measures: Before the race and up to 20 minutes after completing the full race, the weights and heights of volunteers were measured and a 10 mL blood sample was drawn from an antecubital vein. Aliquots of washed/lysed red blood cells and plasma/serum samples were stored at −80°C. Lipid peroxidation, protein carbonylation, superoxide dismutase and catalase activities, and cytokines levels [tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, IL-10, and IL-1ra] were determined. Results: After the IR, the results showed a significant increase in TBARS levels (prerace = 1.15 ± 0.11; postrace = 1.98 ± 0.27), lipid hydroperoxide content (prerace = 0.75 ± 0.03; postrace = 1.46 ± 0.18), protein carbonylation (prerace = 0.67 ± 0.12; postrace = 2 0.15 ± 0.60), superoxide dismutase (prerace = 2.67 ± 0.62; postrace = 3.97 ± 1.48), and catalase (prerace = 1.48 ± 0.18; postrace = 2.84 ± 0.39). TNF-α, IL-6, and IL-10 were not detected at basal conditions, but all markers were significantly increased after the IR (TNF-α: prerace = ND and postrace = 67.47 ± 10.34; IL-6: prerace = ND and postrace = 55.41 ± 3.45; IL-10: prerace = ND and postrace = 122.53 ± 9.69; IL-1ra: prerace = 127.79 ± 25.65 and postrace = 259.51 ± 32.9). Conclusions: An Ironman race provokes significant alterations in oxidative stress and inflammatory parameters. Thus, more studies with other markers and different designs are needed to elucidate the cellular alterations induced by an IR.

Effects of Therapeutic Pulsed Ultrasound and Dimethylsulfoxide (DMSO) Phonophoresis on Parameters of Oxidative Stress in Traumatized Muscle

Many studies have demonstrated an increase in reactive oxygen species (ROS) and oxidative damage markers after muscle damage. Phonophoresis aims to achieve therapeutically relevant concentrations of the transdermally introduced drug in the tissues subjected to the procedure by the use ultrasound waves. The aim of the study was to evaluate the effects on the therapeutic pulsed ultrasound (TPU) together with gel-dimethylsulfoxide (DMSO) in the parameters of muscular damage and oxidative stress. Male Wistar rats were divided randomly into six groups (n=6): sham (uninjured muscle); muscle injury without treatment; muscle injury and treatment with gel-saline (0.9%); muscle injury and treatment with gel-DMSO (15mg/kg); muscle injury and TPU plus gel-saline; and muscle injury and TPU plus gel-DMSO. Gastrocnemius injury was induced by a single impact blunt trauma. TPU (6min duration, frequency of 1.0MHz, intensity of 0.8W/cm(2)) was used 2, 12, 24, 48, 72, 96 and 120h after muscle trauma. The CK and acid phosphatase activity in serum was used as an indicator of skeletal muscle injury. Superoxide anion, TBARS, protein carbonyls, superoxide dismutase (SOD) and catalase (CAT) activity was used as indicators of stress oxidative. Results showed that TPU and gel-DMSO improved muscle healing. Moreover, superoxide anion production, TBARS level and protein carbonyls levels, superoxide dismutase (SOD) and catalase (CAT) activity were all decreased in the group TPU plus gel-DMSO. Our results show that DMSO is effective in the reduction of the muscular lesion and in the oxidative stress after mechanical trauma only when used with TPU. (E-mail: silveira_paulo2004@yahoo.com.br).

Physical Exercise Prevents the Exacerbation of Oxidative Stress Parameters in Chronic Kidney Disease

OBJECTIVE Reactive oxygen species play an important role in the pathogenesis of chronic kidney disease (CKD). Physical exercise was suggested as a useful approach to diminish impaired oxidative defense mechanisms. This study sought to observe the effects of physical training before the induction of renal lesions on oxidative stress parameters in animals induced for CKD. METHODS Twenty-four male Wistar rats were divided into four groups (n = 6): sham, sham plus exercise, CKD, and CKD plus exercise. Exercise groups performed physical training on a treadmill for 8 weeks (up to 1 km/h for 50 min/day, 5 days/week). Forty-eight hours after the final exercise session, a surgical reduction of renal mass was performed (5/6 nephrectomized). Thirty days later, blood samples were collected to determine serum creatinine and urea concentrations, and the right kidney was surgically removed and stored at -70 degrees C for later analysis of superoxide production, antioxidant enzymes (superoxide dismutase and catalase), and oxidative damage of lipids (thiobarbituric acid reactive susbstances level) and proteins (carbonyl groups and sulfhydryl content). RESULTS A significant increase occurred in creatinine and urea levels, superoxide production, antioxidant enzymes, and oxidative damage in the CKD group, compared with sham-treated animals (P < .05). Physical training prevented superoxide production, and decreased the oxidative damage in the CKD group (P < .05), but did not increase the effect of antioxidants. CONCLUSION Physical training before induction of a renal lesion is capable of improving oxidative damage parameters and oxidant production, without altering renal function and the antioxidant defense system.

Effects of Mikania glomerata Spreng. and Mikania laevigata Schultz Bip. ex Baker (Asteraceae) Extracts on Pulmonary Inflammation and Oxidative Stress Caused by Acute Coal Dust Exposure

Several studies have reported biological effects of Mikania glomerata and Mikania laevigata, used in Brazilian folk medicine for respiratory diseases. Pneumoconiosis is characterized by pulmonary inflammation caused by coal dust exposure. In this work, we evaluated the effect of pretreatment with M. glomerata and M. laevigata extracts (MGE and MLE, respectively) (100 mg/kg, s.c.) on inflammatory and oxidative stress parameters in lung of rats subjected to a single coal dust intratracheal instillation. Rats were pretreated for 2 weeks with saline solution, MGE, or MLE. On day 15, the animals were anesthetized, and gross mineral coal dust or saline solutions were administered directly in the lung by intratracheal instillation. Fifteen days after coal dust instillation, the animals were killed. Bronchoalveolar lavage (BAL) was obtained; total cell count and lactate dehydrogenase (LDH) activity were determined. In the lung, myeloperoxidase activity, thiobarbituric acid-reactive substances (TBARS) level, and protein carbonyl and sulfhydryl contents were evaluated. In BAL of treated animals, we verified an increased total cell count and LDH activity. MGE and MLE prevented the increase in cell count, but only MLE prevented the increase in LDH. Myeloperoxidase and TBARS levels were not affected, protein carbonylation was increased, and the protein thiol levels were decreased by acute coal dust intratracheal administration. The findings also suggest that both extracts present an important protective effect on the oxidation of thiol groups. Moreover, pretreatment with MGE and MLE also diminished lung inflammatory infiltration induced by coal dust, as assessed by histopathologic analyses. The present study indicates that M. glomerata and M. laevigata might become good candidates for the prevention of lung oxidative injury caused by coal dust exposure.