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OBJECTIVE To evaluate the antiinflammatory and analgesic effects of sepiapterin reductase (SPR) inhibition in a mouse model of inflammatory joint disease, and to determine whether urinary sepiapterin levels, as measured in mice and healthy human volunteers, could be useful as a noninvasive, translational biomarker of SPR inhibition/target engagement. METHODS The collagen antibody-induced arthritis (CAIA) model was used to induce joint inflammation in mice. The effects of pharmacologic inhibition of SPR on thresholds of heat-, cold-, and mechanical-evoked pain sensitivity and on signs of inflammation were tested in mice with CAIA. In addition, mice and healthy human volunteers were treated with SPR inhibitors, and changes in urinary sepiapterin levels were analyzed by high-performance liquid chromatography. RESULTS CAIA in mice was characterized by 2 phases: in the acute inflammation (early) phase, joint inflammation and heat-, mechanical-, and cold-induced pain hypersensitivity were present, while in the postinflammation (late) phase, no joint inflammation was observed but heat- and mechanical-induced hypersensitivity, but not cold hypersensitivity, were present. Inhibition of SPR in mice with CAIA significantly attenuated the heat-induced hyperalgesia in both phases, and the mechanical allodynia in the late phase. Signs of inflammation were unaffected by SPR inhibition. Urinary tetrahydrobiopterin levels, as a marker of inflammatory pain, were increased during inflammation in mice with CAIA (2-fold increase over controls; P < 0.05) and significantly reduced by SPR inhibition (P < 0.05 versus vehicle-treated mice). Increased urinary sepiapterin levels in the presence of SPR inhibition in both mice and healthy human volunteers were associated with high sensitivity (70-85%) and high specificity (82-88%) for the prediction of SPR inhibition/target engagement. CONCLUSION SPR inhibition reduces the pain associated with joint inflammation, thus showing its potential utility as an analgesic strategy for inflammatory joint pain. In addition, SPR inhibition increases urinary sepiapterin levels, indicating the potential of this measurement as a noninvasive biomarker of target engagement of SPR inhibitors, such as sulfasalazine, a disease-modifying antirheumatic drug that is currently used as a first-line treatment for rheumatoid arthritis.

Our objective was to investigate whether the pulp and paper mill industry effluent could affect the testis and Sertoli cells in a fast exposure period. For this, the present study was carried out in immature rats at 10-day-old. Testis treated in vitro with 4% effluent for 1 h presented changes in energy metabolism in terms of a decrease in lactate content and glucose uptake. Elevation in GSH content, as an antioxidant defense mechanism, was also detected. Sertoli cells treated with 4% effluent for 1 hour showed alterations in the mitochondrial metabolism that favor the decoupling of oxidative phosphorylation and the generation of oxygen reactive species and also a time and concentration-dependent delay secretion of acidic vesicles. Our results showed that pollutants present in the pulp and paper mill effluents, in a short time of exposure, are capable of inducing alterations in important metabolic functions in the testis and in Sertoli cells that are crucial for the correct progression of spermatogenesis and fertility.

1α,25-Dihydroxyvitamin D3 (1,25-D3) is critical for the maintenance of normal male reproduction since reduced fertility is observed in vitamin D-deficient rats. Gamma-glutamyl transpeptidase (GGT) is a membrane-bound enzyme that is localized on Sertoli cells and catalyses the transfer of the gamma-glutamyl residues to an amino acid or peptide acceptor. Sertoli cells are also responsible for providing nutrients, as lactate, to the development of germ cells. The aim of this study was to investigate the effect and the mechanism of action of 1,25-D3 on GGT on Sertoli cell functions from 30-day-old immature rat testis. Results demonstrated that 1,25-D3 stimulates GGT activity at Sertoli cells plasma membrane through a PKA-dependent mechanism of action, which was not dependent of active de novo protein synthesis. The hormone increases glucose uptake, as well as lactate production and release by Sertoli cells without altering the reactive oxygen species (ROS) generation. In addition, 1,25-D3 did not change reduced glutathione (GSH) amount or oxygen consumption, and diminished Sertoli cell death. These findings demonstrate that 1,25-D3 stimulatory effect on GGT activity, glucose uptake, LDH activity and lactate production seem to be an important contribution of Sertoli cells for germ cells nutrition and for a full and active ongoing spermatogenesis.

Stroke is a major cause of disability and death worldwide. Oxygen and glucose deprivation (OGD) in brain tissue preparations can reproduce several pathological features induced by stroke providing a valuable ex vivo protocol for studying the mechanism of action of neuroprotective agents. Guanosine, an endogenous guanine nucleoside, promotes neuroprotection in vivo and in vitro models of neurotoxicity. We previously showed that guanosine protective effect was mimicked by inhibition of nitric oxide synthases (NOS) activity. This study was designed to investigate the involvement of nitric oxide (NO) in the mechanisms related to the protective role of guanosine in rat hippocampal slices subjected to OGD followed by reoxygenation (OGD/R). Guanosine (100 μM) and the pan-NOS inhibitor, l-NAME (1 mM) afforded protection to hippocampal slices subjected to OGD/R. The presence of NO donors, DETA-NO (800 μM) or SNP (5 μM) increased reactive species production, and abolished the protective effect of guanosine or l-NAME against OGD/R. Guanosine or l-NAME treatment prevented the impaired ATP production, lactate release, and glutamate uptake following OGD/R. The presence of a NO donor also abolished the beneficial effects of guanosine or l-NAME on bioenergetics and glutamate uptake. These results showed, for the first time, that guanosine may regulate cellular bioenergetics in hippocampal slices subjected to OGD/R injury by a mechanism that involves the modulation of NO levels.

Benefits of exercise have been documented for many diseases with a chronic progression, including obesity, diabetes mellitus, cardiovascular diseases, neurodegenerative diseases, certain types of cancers, and overall mortality. Low-grade systemic inflammation is a key component of these pathologies and it has been demonstrated that can be prevented by performing regularly physical exercise. The aim of this study was to examine the effect of lipopolysaccharide (LPS)-induced inflammation on glucose and insulin tolerance, exercise performance, production of urinary neopterin and striatal neurotransmitters levels in adult male C57BL/6 mice. Increased blood glucose clearance and insulin sensitivity were observed after a single administration of glucose (2 g/kg, p.o.) or insulin (0.5 U/kg, i.p.). However, the repeated injection of LPS (0.33 mg/kg/day, i.p.) decreased glucose tolerance and increase urinary neopterin levels, pointing to systemic inflammation. In parallel to the urinary-increased neopterin, it was observed a significant reduction in the striatal dopamine levels and an increase in the serotonin/dopamine ratio. While a single LPS injection (0.33 mg/kg, i.p.) showed impaired performance in the incremental loading test (10 m/min, with 2 m/min increment every 3 min, at 9% grade), a moderate physical exercise protocol (treadmill for three weeks; 5 sessions/week; up to 50 min/day) prevented the exacerbation of immune system activation and preserved mitochondrial activity in skeletal muscle from mice with continuous LPS infusion (infusion pumps: 0.83 mg/kg/day, i.p.). In conclusion, the peripheral-induced inflammation elicited metabolic alterations that provoked impairment in striatal dopamine metabolism. The moderate exercise prevented the increase of urinary neopterin and preserved mitochondrial activity under LPS-induced inflammatory conditions.

The aim of this study was to evaluate the effects of therapeutic pulsed ultrasound with gold nanoparticles on oxidative stress parameters after traumatic muscle injury in Wistar rats. The animals were randomly divided into nine groups (n = 6 each): sham (uninjured muscle); muscle injury without treatment; muscle injury and treatment with dimethyl sulfoxide (15 mg/kg); muscle injury and treatment with gold nanoparticles (27 µg); muscle injury and treatment with dimethyl sulfoxide + gold nanoparticles (Plus); muscle injury and therapeutic pulsed ultrasound; muscle injury and therapeutic pulsed ultrasound + dimethyl sulfoxide; muscle injury and therapeutic pulsed ultrasound + gold nanoparticles; and muscle injury and therapeutic pulsed ultrasound + Plus. Gastrocnemius injury was induced by a single-impact blunt trauma. Therapeutic pulsed ultrasound (6-min application, frequency 1.0 MHz, intensity 0.8 W/cm(2)) was used 2, 12, 24, and 48 h after trauma. Mitochondrial superoxide generation, lipid peroxidation, and protein carbonylation, and the activities of superoxide dismutase, glutathione peroxidase, and catalase were evaluated. The increase in the superoxide production and TBARS and carbonyl levels observed in the control group after muscle damage were reduced in animals exposed to therapeutic pulsed ultrasound plus nanoparticles. Similarly, antioxidants enzymes showed a decreased activity with the same treatment. Our work suggest that therapeutic pulsed ultrasound + dimethyl sulfoxide + gold nanoparticles has beneficial effects on the muscle healing process by inducing a decrease in oxidative stress parameters and most likely decreasing the deleterious effects of the inflammatory response.

The purpose of the present investigation was to identify muscle damage, inflammatory response and oxidative stress blood markers in athletes undertaking the ultra-endurance MultiSport Brazil race. Eleven well-trained male athletes (34.3 ± 3.1 years, 74.0 ± 7.6 kg; 172.2 ± 5.1 cm) participated in the study and performed the race, which consisted of about 90 km of alternating off-road running, mountain biking and kayaking. Twelve hours before and up to 15 minutes after the race a 10 mL blood sample was drawn in order to measure the following parameters: lactate dehydrogenase and creatine kinase activities, lipid peroxidation, catalase activity, protein carbonylation, respiratory chain complexes I, II and IV activities, oxygen consumption and neopterin concentrations. After the race, plasma lactate dehydrogenase and creatine kinase activities were significantly increased. Erythrocyte TBA-RS levels and plasma protein carbonylation were markedly augmented in post-race samples. Additionally, mitochondrial complex II activity and oxygen consumption in post-race platelet-rich plasma were also increased. These altered biochemical parameters were accompanied by increased plasma neopterin levels. The ultra-endurance event provoked systemic inflammation (increased neopterin) accompanied by marked oxidative stress, likely by increasing oxidative metabolism (increased oxidative mitochondrial function). This might be advantageous during prolonged exercise, mainly for efficient substrate oxidation at the mitochondrial level, even when tissue damage is induced.

Introduction The aim of the study was to evaluate the effects of TPU together with DMSO on oxidative stress parameters after eccentric exercise. Methods Thirty and six animals were divided in control; eccentric exercise (EE); EE + saline gel 0.9%; EE + TPU 0.8 W/cm 2 ; EE + DMSO gel; EE + TPU + DMSO gel and submitted to one 90-min downhill run (1.0 km h −1 ). TPU was used 2, 12, 24, 46 h after exercise session and 48 h after the animals were killed and the gastrocnemius muscles were surgically removed. Production of superoxide anion, creatine kinase (CK) levels, lipoperoxidation, carbonylation, and antioxidants enzymes were analyzed. Results Showed that TPU and gel-DMSO improved muscle healing. Moreover, superoxide anion production, TBARS level and protein carbonyls levels, superoxide dismutase and catalase activity were all decreased in the group TPU plus gel-DMSO. Discussion Our results show that DMSO is effective in the reduction of the muscular lesion and in the oxidative stress after eccentric exercise only when used with TPU.

Infrequent exercise, typically involving eccentric actions, has been shown to cause oxidative stress and to damage muscle tissue. High taurine levels are present in skeletal muscle and may play a role in cellular defences against free radical-mediated damage. This study investigates the effects of taurine supplementation on oxidative stress biomarkers after eccentric exercise (EE). Twenty-four male rats were divided into the following groups (n = 6): control; EE; EE plus taurine (EE + Taurine); EE plus saline (EE + Saline). Taurine was administered as a 1-ml 300 mg kg−1 per body weight (BW) day−1 solution in water by gavage, for 15 consecutive days. Starting on the 14th day of supplementation, the animals were submitted to one 90-min downhill run session and constant velocity of 1·0 km h−1. Forty-eight hours after the exercise session, the animals were killed and the quadriceps muscles were surgically removed. Production of superoxide anion, creatine kinase (CK) levels, lipoperoxidation, carbonylation, total thiol content and antioxidant enzyme were analysed. Taurine supplementation was found to decrease superoxide radical production, CK, lipoperoxidation and carbonylation levels and increased total thiol content in skeletal muscle, but it did not affect antioxidant enzyme activity after EE. The present study suggests that taurine affects skeletal muscle contraction by decreasing oxidative stress, in association with decreased superoxide radical production. Copyright © 2010 John Wiley & Sons, Ltd.

Several studies have investigated the biochemical response changes that take place in Ironman triathletes, but there are few data on oxidative stress changes. The objective of this study was to investigate oxidative stress parameters in triathletes after an Ironman event. The sample consisted of eighteen male triathletes, with a mean age of 34.5 ± 2.15 years, weight 69.3 ± 1.9 kg, and height 1.71 ± 0.18 m. The Ironman triathlon consists of a 3.8-km swim, a 180-km bicycle ride, and a 42.2-km (marathon) run. Before the competition and immediately after its conclusion, 10-mL blood samples were collected, centrifuged and frozen at -80oC for subsequent analysis. Total antioxidant capacity, lipid peroxidation, protein carbonylation, and total thiol content were measured. The results showed a significant increase in all markers after the event (p

To investigate the effects physical training exerts on markers of oxidative stress in rats with chronic kidney disease (CKD).Twenty-four male Wistar rats were divided into four groups (n=6): sham, CKD, exercise-sham and exercise-CKD. Surgical reduction of the renal mass was performed (5/6 nephrectomized) and exercise was conducted on a treadmill (50 min/day up to 1 km/h for, 5 days/week for eight weeks). Forty-eight hours after the last exercise session, blood (1 mL) was collected from the abdominal aorta and animals were decapitated. The left kidney was surgically removed and stored at -70 °C for subsequent analysis.An increase was observed in creatinine and urea levels, superoxide production, antioxidant enzymes, and oxidative damage in the CKD group, as compared to sham animals (p0.05). Physical training made superoxide production and oxidative damage decrease in the CKD group (p0.05), increasing SOD and GPX activity, though it did not increase the antioxidant effects of CAT, and renal parameters.Even without altering renal function in animals induced to CKD model, the results show that physical training is an important component in the treatment of CKD, because it exerted a positive influence on oxidative stress parameters, especially on the reduction in superoxide production and oxidative damage, as well as an improvement in the antioxidant defense system, like SOD and GPX.

It has been demonstrated that reactive oxygen species (ROS) formation and oxidative damage markers are increased after muscle damage. Recent studies have demonstrated that low-level laser therapy (LLLT) modulates many biochemical processes mainly those related to reduction of muscular injures, increment of mitochondrial respiration and ATP synthesis, as well as acceleration of the healing process. The objective of the present investigation was to verify the influence of LLLT in some parameters of muscular injury, oxidative damage, antioxidant activity, and synthesis of collagen after traumatic muscular injury. Adult male Wistar rats were divided randomly into three groups (n = 6), namely, sham (uninjured muscle), muscle injury without treatment, and muscle injury with LLLT (GaAs, 904 nm). Each treated point received 5 J/cm(2) or 0.5 J of energy density (12.5 s) and 2.5 J per treatment (five regions). LLLT was administered 2, 12, 24, 48, 72, 96, and 120 h after muscle trauma. The serum creatine kinase activity was used as an index of skeletal muscle injury. Superoxide anion, thiobarbituric acid reactive substance (TBARS) measurement, and superoxide dismutase (SOD) activity were used as indicators of oxidative stress. In order to assess the synthesis of collagen, levels of hydroxyproline were measured. Our results have shown that the model of traumatic injury induces a significant increase in serum creatine kinase activity, hydroxyproline content, superoxide anion production, TBARS level, and activity of SOD compared to control. LLLT accelerated the muscular healing by significantly decreasing superoxide anion production, TBARS levels, the activity of SOD, and hydroxyproline content. The data strongly indicate that increased ROS production and augmented collagen synthesis are elicited by traumatic muscular injury, effects that were significantly decreased by LLLT.

This study investigated the acute effect of two swimming sessions on oxidative stress markers in trained individuals. Twelve male volunteers, students from UNESC (Universidade do Extremo Sul Catarinense, Criciuma, Santa Catarina, Brazil), with a mean age of 28 ± 7 years, initial weight of 72.9 ± 9 kg and height of 1.75 ± 0.08 cm, participated in the study. Blood samples were collected 24 hours before the sessions, immediately after the first and second session, and 24 hours after the end of the sessions. Aliquots were washed, red blood cells were lysed and plasma samples were stored at -80 oC until the time of the biochemical assays. Creatine kinase (CK) activity, lipid peroxidation level, protein carbonylation, thiol content and catalase activity were determined. The results showed a significant increase in CK, lipoperoxidation and protein carbonylation and a decrease in thiol content after the second swimming session (p