Early life neuroimmune challenge protects the brain after sepsis in adult rats.

Evidences has suggested that in the early life the innate immune system presents plasticity and the time and dose-adequate stimuli in this phase may program long-lasting immunological responses that persist until adulthood. We aimed to evaluate whether LPS challenge in early childhood period may modulate brain alterations after sepsis in adult life. Experiments were performed to evaluate the LPS challenge in early childhood or adult period on acute and long-term brain alterations after model of sepsis by cecal ligation and perforation (CLP) in adult life. Wistar rats were divided in saline+sham, LPS+sham, saline+CLP and LPS+CLP groups to determine cytokine levels and nitrite/nitrate concentration in cerebrospinal fluid (CSF); oxidative damage, activity of antioxidant enzymes (superoxide dismutase-SOD and catalase-CAT); blood brain barrier (BBB) permeability; myeloperoxidase (MPO) and epigenetic enzymes activities in the hippocampus and prefrontal cortex (at 24 h after CLP) and cognitive function, survival and brain-derived neurotrophic factor (BDNF) level (at ten days after CLP). LPS-preconditioning in early life could lead to decreased levels of TNF-α and IL-6 and oxidative damage parameters in the brain after CLP in adult rats. In addition, LPS-preconditioning in early life increase CAT activity, attenuates the BBB permeability and epigenetic enzymes alterations and in long term, improves the memory, BDNF levels and survival. In conclusion, rats submitted to CLP in adulthood displayed acute neuroinflammation, neurochemical and epigenetic alteration improvement accompanied in long term by an increase in survival, neurotrophin level and memory performance when preconditioned with LPS in the early life.

Fish oil-rich lipid emulsion modulates neuroinflammation and prevents long-term cognitive dysfunction after sepsis.

OBJECTIVES: Sepsis is a severe organic dysfunction caused by an infection that affects the normal regulation of several organ systems, including the central nervous system. Inflammation and oxidative stress play crucial roles in the development of brain dysfunction in sepsis. The aim of this study was to determine the effect of a fish oil (FO)-55-enriched lipid emulsion as an important anti-inflammatory compound on brain dysfunction in septic rats. METHODS: Wistar rats were subjected to sepsis by cecal ligation and perforation (CLP) or sham (control) and treated orally with FO (600 µL/kg after CLP) or vehicle (saline; sal). Animals were divided into sham+sal, sham+FO, CLP+sal and CLP+FO groups. At 24 h and 10 d after surgery, the hippocampus, prefrontal cortex, and total cortex were obtained and assayed for levels of interleukin (IL)-1ß and IL-10, blood-brain barrier permeability, nitrite/nitrate concentration, myeloperoxidase activity, thiobarbituric acid reactive species formation, protein carbonyls, superoxide dismutase and catalase activity, and brain-derived neurotrophic factor levels. Behavioral tasks were performed 10 d after surgery. RESULTS: FO reduced BBB permeability in the prefrontal cortex and total cortex of septic rats, decreased IL-1ß levels and protein carbonylation in all brain structures, and diminished myeloperoxidase activity in the hippocampus and prefrontal cortex. FO enhanced brain-derived neurotrophic factor levels in the hippocampus and prefrontal cortex and prevented cognitive impairment. CONCLUSIONS: FO diminishes the negative effect of polymicrobial sepsis in the rat brain by reducing inflammatory and oxidative stress markers.

Manual Therapy Reduces Pain Behavior and Oxidative Stress in a Murine Model of Complex Regional Pain Syndrome Type I.

Complex regional pain syndrome type I (CRPS-I) is a chronic painful condition. We investigated whether manual therapy (MT), in a chronic post-ischemia pain (CPIP) model, is capable of reducing pain behavior and oxidative stress. Male Swiss mice were subjected to ischemia-reperfusion (IR) to mimic CRPS-I. Animals received ankle joint mobilization 48h after the IR procedure, and response to mechanical stimuli was evaluated. For biochemical analyses, mitochondrial function as well as oxidative stress thiobarbituric acid reactive substances (TBARS), protein carbonyls, antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) levels were determined. IR induced mechanical hyperalgesia which was subsequently reduced by acute MT treatment. The concentrations of oxidative stress parameters were increased following IR with MT treatment preventing these increases in malondialdehyde (MDA) and carbonyls protein. IR diminished the levels of SOD and CAT activity and MT treatment prevented this decrease in CAT but not in SOD activity. IR also diminished mitochondrial complex activity, and MT treatment was ineffective in preventing this decrease. In conclusion, repeated sessions of MT resulted in antihyperalgesic effects mediated, at least partially, through the prevention of an increase of MDA and protein carbonyls levels and an improvement in the antioxidant defense system.

Antioxidant Effect of Far Infrared Radiation Produced by Bioceramics in Individuals with Intermittent Claudication: A Randomized, Controlled Pilot Study.

BACKGROUND: Biomedical research has recently incorporated bioceramics applications into new health care approaches. OBJECTIVE: This study evaluated the effect of far infrared-emitting bioceramics wraps in the treatment of intermittent claudication. METHODS: This is a randomized double-blind placebo-controlled pilot study. Thirty-five patients met the criteria and were randomized into either control (placebo wraps) or bioceramics group (far infrared emitting-ceramics wraps) and assessed over a 90-day period for the following outcomes: six-minute walk test (6MWT), ankle-brachial index (ABI), Flow-mediated arterial dilation (FMD), quality of life and claudication. Oxidative stress and inflammatory biomarkers were measured in plasma of patients. RESULTS: Intervention induced a decrease in oxidative stress, with significant lower levels of reactive substances to thiobarbituric acid (TBARS), as well as increase in superoxide dismutase and catalase enzyme activities. There was an increase in the environment subscale of the quality of life questionnaire. No statistically significant differences were found in the inflammatory cytokines, 6MWT, ABI and FMV evaluations. CONCLUSIONS: In Sum, FIR treatment improved oxidative stress profile and quality-of-life of patients with intermittent claudication. The study was registered into the ensaiosclinicos.gov.br (Registro Brasileiro de Ensaios Clínicos [ReBEC]) (RBR-7nr6sy register number).

Dimethyl Fumarate Limits Neuroinflammation and Oxidative Stress and Improves Cognitive Impairment After Polymicrobial Sepsis.

Sepsis is caused by a dysregulated host response to infection, often associated with acute central nervous system (CNS) dysfunction, which results in long-term cognitive impairment. Dimethyl fumarate (DMF) is an important agent against inflammatory response and reactive species in CNS disorders. Evaluate the effect of DMF on acute and long-term brain dysfunction after experimental sepsis in rats. Male Wistar rats were submitted to the cecal ligation and puncture (CLP) model. The groups were divided into sham (control) + vehicle, sham + NAC, sham + DMF, CLP + vehicle, CLP + NAC, and CLP + DMF. The animals were treated with DMF (15 mg/kg at 0 and 12 h after CLP, per gavage) and the administration of n-acetylcysteine (NAC) (20 mg/kg; 3, 6, and 12 h after CLP, subcutaneously) was used as positive control. Twenty-four hours after CLP, cytokines, myeloperoxidase (MPO), nitrite/nitrate (N/N), oxidative damage to lipids and proteins, and antioxidant enzymes were evaluated in the hippocampus, total cortex, and prefrontal cortex. At 10 days after sepsis induction, behavioral tests were performed to assess cognitive damage. We observed an increase in cytokine levels, MPO activity, N/N concentration, and oxidative damage, a reduction in SOD and GPx activity in the brain structures, and cognitive damage in CLP rats. DMF treatment was effective in reversing these parameters. DMF reduces sepsis-induced neuroinflammation, oxidative stress, and cognitive impairment in rats subjected to the CLP model.

Maternal immune activation induced by lipopolysaccharide triggers immune response in pregnant mother and fetus, and induces behavioral impairment in adult rats.

Evidence suggest that prenatal immune system disturbance contributes largely to the pathophysiology of neuropsychiatric disorders. We investigated if maternal immune activation (MIA) could induce inflammatory alterations in fetal brain and pregnant rats. Adult rats subjected to MIA also were investigated to evaluate if ketamine potentiates the effects of infection. On gestational day 15, Wistar pregnant rats received lipopolysaccharide (LPS) to induce MIA. After 6, 12 and 24 h, fetus brain, placenta, and amniotic fluid were collected to evaluate early effects of LPS. MIA increased oxidative stress and expression of metalloproteinase in the amniotic fluid and fetal brain. The blood brain barrier (BBB) integrity in the hippocampus and cortex as well integrity of placental barrier (PB) in the placenta and fetus brain were dysregulated after LPS induction. We observed elevated pro- and anti-inflammatory cytokines after LPS in fetal brain. Other group of rats from postnatal day (PND) 54 after LPS received injection of ketamine at the doses of 5, 15, and 25 mg/kg. On PND 60 rats were subjected to the memories tests, spontaneous locomotor activity, and pre-pulse inhibition test (PPI). Rats that receive MIA plus ketamine had memory impairment and a deficit in the PPI. Neurotrophins were increased in the hippocampus and reduced in the prefrontal cortex in the LPS plus ketamine group. MIA induced oxidative stress and inflammatory changes that could be, at least in part, related to the dysfunction in the BBB and PB permeability of pregnant rats and offspring. Besides, this also generates behavioral deficits in the rat adulthood's that are potentiated by ketamine.

Vitamin B6 Reduces Neurochemical and Long-Term Cognitive Alterations After Polymicrobial Sepsis: Involvement of the Kynurenine Pathway Modulation.

Neurological dysfunction as a result of neuroinflammation has been reported in sepsis and cause high mortality. High levels of cytokines stimulate the formation of neurotoxic metabolites by kynurenine (KYN) pathway. Vitamin B6 (vit B6) has anti-inflammatory and antioxidant properties and also acts as a cofactor for enzymes of the KYN pathway. Thus, by using a relevant animal model of polymicrobial sepsis, we studied the effect of vit B6 on the KYN pathway, acute neurochemical and neuroinflammatory parameters, and cognitive dysfunction in rats. Male Wistar rats (250-300 g) were submitted to cecal ligation and perforation (CLP) and divided into sham + saline, sham + vit B6, CLP + saline, and CLP + vit B6 (600 mg/kg, s.c.) groups. Twenty-four hours later, the prefrontal cortex and hippocampus were removed for neurochemical and neuroinflammatory analyses. Animals were followed for 10 days to determine survival rate, when cognitive function was assessed by behavioral tests. Vitamin B6 interfered in the activation of kynurenine pathway, which led to an improvement in neurochemical and neuroinflammatory parameters and, consequently, in the cognitive functions of septic animals. Thus, the results indicate that vit B6 exerts neuroprotective effects in acute and late consequences after sepsis.

Alpha-lipoic acid attenuates acute neuroinflammation and long-term cognitive impairment after polymicrobial sepsis.

Sepsis is a complication of an infection which imbalance the normal regulation of several organ systems, including the central nervous system (CNS). Evidence points towards inflammation and oxidative stress as major steps associated with brain dysfunction in sepsis. Thus, we investigated the α-lipoic acid (ALA) effect as an important antioxidant compound on brain dysfunction in rats. Wistar rats were subjected to sepsis by cecal ligation and perforation (CLP) or sham (control) and treated orally with ALA (200 mg/kg after CLP) or vehicle. Animals were divided into sham + saline, sham + ALA, CLP + saline and CLP + ALA groups. Twelve, 24 h and 10 days after surgery, the hippocampus, prefrontal cortex and cortex were obtained and assayed for levels of TNF-α and IL-1ß, blood brain barrier (BBB) permeability, nitrite/nitrate concentration, myeloperoxidase (MPO) activity, thiobarbituric acid reactive species (TBARS) formation, protein carbonyls, superoxide dismutase (SOD) and catalase (CAT) activity and neurotrophins levels. Behavioral tasks were performed 10 days after surgery. ALA reduced BBB permeability and TNF-α levels in hippocampus in 24 h and IL-1ß levels and MPO activity in hippocampus and prefrontal cortex in 24 h. ALA reduced nitrite/nitrate concentration and lipid peroxidation in 24 h in all structures and protein carbonylation in 12 and 24 h in hippocampus and cortex. CAT activity increased in the hippocampus and cortex in all times. ALA enhanced NGF levels in hippocampus and cortex and prevented cognitive impairment. Our data demonstrates that ALA reduces the consequences of polymicrobial sepsis in rats by decreasing inflammatory and oxidative stress parameters in the brain.

Temporal changes of oxidative stress markers in Escherichia coli K1-induced experimental meningitis in a neonatal rat model.

Despite advances in antimicrobial therapy and advanced critical care neonatal bacterial meningitis has a mortality rate of over 10% and induces neurological sequelae in 20-50% of cases. Escherichia coli K1 (E. coli K1) is the most common gram-negative organism causing neonatal meningitis and is the second most common cause behind group B streptococcus. We previously reported that an E. coli K1 experimental meningitis infection in neonatal rats resulted in habituation and aversive memory impairment and a significant increase in cytokine levels in adulthood. In this present study, we investigated the oxidative stress profile including malondialdehyde (MDA) levels, carbonyl protein formation, myeloperoxidase activity (MPO) activity, superoxide dismutase (SOD) activity and catalase (CAT) activity 6, 12, 24, 48, 72 and 96h after E. coli K1 experimental meningitis infection. In addition, sulfhydryl groups, nitrite and nitrate levels and activity of the mitochondrial respiratory chain enzymes were also measured in the frontal cortex and hippocampus of neonatal rats. The results from this study demonstrated a significant increase in MDA, protein carbonyls and MPO activity and a simultaneous decrease in SOD activity in the hippocampus of the neonatal meningitis survivors but the same was not observed in frontal cortex. In addition, we also observed a significant increase in complex IV activity in the hippocampus and frontal cortex of meningitis survivor rats. Thus, the results from this study reaffirmed the possible role of oxidative stress, nitric oxide and its related compounds in the complex pathophysiology of E. coli K1-induced bacterial meningitis.

Healing effect of Dillenia indica fruit extracts standardized to betulinic acid on ultraviolet radiation-induced psoriasis-like wounds in rats.

CONTEXT: Dillenia indica Linn. (Dilleniaceae) is traditionally used to treat skin inflammation. OBJECTIVE: This study evaluated the healing effect of Dillenia indica fruit extracts on induced psoriasis-like wounds in Wistar rats. MATERIALS AND METHODS: Extracts were standardized to betulinic acid, including an aqueous ethanolic extract (AEE), ethyl acetate extract (EAE) and petroleum ether extract. Effects against lipid peroxidation were assessed in vitro. Wounds were created at rat tails (n = 12). Topical treatments were applied once daily for 7 days (1 mL of AEE or EAE at 5 or 50 mg/mL). Maximal dose was defined by the extract solubility. A 10-fold lower dose was also tested. Positive and negative controls were treated with clobetasol (0.5 mg/mL) or excipient. Half of each group was euthanized for histology. The remaining animals were observed for 20 days for wound measurements. RESULTS: Yields of AEE and EAE were 4.3 and 0.7%, respectively. Betulinic acid concentrations in AEE and EAE were 4.6 and 107.6 mg/g. Extracts neutralized lipid peroxidation in vitro at 0.02 µg/mL, accelerating healing at 50 mg/mL. Complete healing in mice treated with AEE occurred 16 days after wound induction. This time was 14 and 12 days in mice treated with EAE and clobetasol. Compared to orthokeratosis, parakeratosis was reduced by AEE (25%), EAE (45%) and clobetasol (55%). EAE caused superior protection against biomolecules oxidation of skin compared to AEE. DISCUSSION AND CONCLUSION: EAE exhibited activity closer to that of clobetasol. Betulinic acid may be an active constituent, which should be assessed in future studies.

Obesity Exacerbates Sepsis-Induced Oxidative Damage in Organs.

Sepsis progression is linked to the imbalance between reactive oxygen species and antioxidant enzymes. Sepsis affects multiple organs, but when associated with a chronic inflammatory disease, such as obesity, it may be exacerbated. We hypothesized that obesity could aggravate the oxidative damage to peripheral organs of rats submitted to an animal model of sepsis. Male Wistar rats aged 8 weeks received hypercaloric nutrition for 2 months to induce obesity. Sepsis was induced by cecal ligation and puncture (CLP) procedure, and sham-operated rats were considered as control group. The experimental groups were divided into sham + eutrophic, sham + obese, CLP + eutrophic, and CLP + obese. Twelve and 24 h after surgery, oxidative damage to lipids and proteins and superoxide dismutase (SOD) and catalase (CAT) activities were evaluated in the liver, lung, kidney, and heart. The data indicate that obese rats subjected to sepsis present oxidative stress mainly in the lung and liver. This alteration reflected an oxidative damage to lipids and proteins and an imbalance of SOD and CAT levels, especially 24 h after sepsis. It follows that obesity due to its pro-inflammatory phenotype can aggravate sepsis-induced damage in peripheral organs.

Preoperative vitamin C supplementation improves colorectal anastomotic healing and biochemical parameters in malnourished rats.

PURPOSES: The objective of this study was to evaluate the effect of supplementation with vitamin C on intestinal anastomosis healing in malnourished rats. METHODS: Male Wistar rats were divided into three groups: (1) sham, well-nourished rats that received vehicle; (2) FR+Veh, rats that were subjected to food restriction and received vehicle; and (3) FR+VC, rats that were subjected to food restriction and received vitamin C. Four days before surgery, the animals received vitamin C (100 mg/kg/day) via gavage and underwent colon resection with anastomosis in a single plane. The survival rate of rats was monitored until day 7 after surgery. Regarding anastomosis tissues, we examined intra-abdominal adhesion index, hydroxyproline content, collagen density, inflammatory parameters, and oxidative damage to proteins and lipids. RESULTS: Malnutrition decreases body weight and increases mortality; the survival rate was 90 % in group 1, 60 % in group 2, and 80 % in group 3. Vitamin C was able to increase hydroxyproline concentration and density of collagen and decrease the intra-abdominal adhesion index, as well as the infiltration of neutrophils and oxidative damage to proteins in malnourished rats compared to group treated with vehicle. CONCLUSIONS: Preoperative vitamin C supplementation can improve the intestinal anastomosis healing, biochemical alterations, and prolong survival in rats subjected to food restriction.

Diphenyl diselenide attenuates oxidative stress and inflammatory parameters in ulcerative colitis: A comparison with ebselen.

OBJETIVE: The aim of this study was to evaluate the effects of diphenyl diselenide (PhSe)2 and ebselen (EB) in ulcerative colitis (UC) induced by dextran sulfate sodium (DSS) in rats. METHODS: The effects of (PhSe)2 and EB in rats submitted to DSS-induced colitis were determined by measurement of oxidative stress parameters, inflammatory response and bowel histopathological alterations. RESULTS: Animals developed moderate to severe neutrophil infiltration in histopathology assay in DSS rats and (PhSe)2 improved this response. Moreover, the treatment with (PhSe)2 decreased the oxidative damage in lipids and proteins, as well as reversed the superoxide dismutase (SOD) and catalase (CAT) levels in rats treated with DSS. EB was able only to reverse damage in lipids and the low levels of SOD in this animal model. CONCLUSIONS: The organoselenium compounds tested demonstrated an anti-inflammatory and antioxidant activity reducing the colon damage, being (PhSe)2 more effective than EB.

Anti-inflammatory and antioxidant activities of aqueous extract of Cecropia glaziovii leaves.

ETHNOPHARMACOLOGICAL RELEVANCE: Cecropia glaziovii Sneth leaves extract is widely used as a traditional folk medicine in Brazil, especially for the treatment of diabetes, and as an antihypertensive and antiinflammatory agent. AIM OF THE STUDY: To investigate the anti-inflammatory and antioxidant properties of crude aqueous extract (CAE) of C. glaziovii leaves. MATERIALS AND METHODS: The in vivo anti-inflammatory and antioxidant effect of the CAE (10-300mg/kg, intragastrically) was investigated in the animal model of pleurisy. The cell migration, proinflammatory cytokines (TNF-α, IL-1ß and IL-6), nitrite/nitrate concentration, myeloperoxidase (MPO) activity, oxidative damage in lipids and proteins, lactate dehydrogenase (LDH) activity and total protein content were also analyzed. Furthermore, the in vitro antioxidant activity of CAE was evaluated by the inhibition of formation of thiobarbituric acid reactive substances (TBARS), induced by free radical generators (H2O2, FeSO4 and AAPH) on a lipid-rich substrate. Hence, the chemical characterizarion of CAE by HPLC was therefore performed. The results showed that the inflammatory process caused by the administration of carragenin (Cg) into the pleural cavity resulted in a substantial increase in inflammatory parameters and oxidative damage. These levels seems to be reversed after CAE treatment in animals with similar results to Dexamethasone (Dex) treatment. Further, the CAE was effective in reducing proinflammatory cytokines, cell infiltrate, MPO activity, nitrite/nitrate concentration, LDH activity, and total protein levels with concomitant attenuation of all parameters associated with oxidative damage induced by Cg. Finally, the CAE presented in vitro antioxidant activity induced by free radical generators at all the concentrations investigated. HPLC analysis confirmed the presence of chlorogenic acid and C-glycosylflavonoids (isoorientin and isovitexin) as the major compounds of the CAE. CONCLUSION: CAE of C. glaziovii exerts significant antiinflammatory and antioxidant activities and this effect can be attributed, at least in part, to the presence of chlorogenic acid and the C-glycosylflavonoids.

Alpha-Lipoic Acid Attenuates Oxidative Damage in Organs After Sepsis.

Sepsis progression is linked with the imbalance between reactive oxygen species and antioxidant enzymes. Thus, the aim of this study was to evaluate the effect of alpha-lipoic acid (ALA), a powerful antioxidant, in organs of rats submitted to sepsis. Male Wistar rats were subjected to sepsis by cecal ligation puncture (CLP) and treated with ALA or vehicle. After CLP (12 and 24 h), the myeloperoxidase (MPO) activity, protein and lipid oxidative damage, and antioxidant enzymes in the liver, kidney, heart, and lung were evaluated. ALA was effective in reducing MPO activity, lipid peroxidation in the liver, and protein carbonylation only in the kidney in 12 h after CLP. In 12 h, SOD activity increased in the kidney and CAT activity in the liver and kidney with ALA treatment. Thus, ALA was able to reduce the inflammation and oxidative stress in the liver and kidney after sepsis in rats.

Antioxidant treatment ameliorates experimental diabetes-induced depressive-like behaviour and reduces oxidative stress in brain and pancreas.

Studies have shown a relationship between diabetes mellitus (DM) and the development of major depressive disorder. Alterations in oxidative stress are associated with the pathophysiology of both diabetes mellitus and major depressive disorder. This study aimed to evaluate the effects of antioxidants N-acetylcysteine and deferoxamine on behaviour and oxidative stress parameters in diabetic rats. To this aim, after induction of diabetes by a single dose of alloxan, Wistar rats were treated with N-acetylcysteine or deferoxamine for 14 days, and then depressive-like behaviour was evaluated. Oxidative stress parameters were assessed in the prefrontal cortex, hippocampus, amygdala, nucleus accumbens and pancreas. Diabetic rats displayed depressive-like behaviour, and treatment with N-acetylcysteine reversed this alteration. Carbonyl protein levels were increased in the prefrontal cortex, hippocampus and pancreas of diabetic rats, and both N-acetylcysteine and deferoxamine reversed these alterations. Lipid damage was increased in the prefrontal cortex, hippocampus, amygdala and pancreas; however, treatment with N-acetylcysteine or deferoxamine reversed lipid damage only in the hippocampus and pancreas. Superoxide dismutase activity was decreased in the amygdala, nucleus accumbens and pancreas of diabetic rats. In diabetic rats, there was a decrease in catalase enzyme activity in the prefrontal cortex, amygdala, nucleus accumbens and pancreas, but an increase in the hippocampus. Treatment with antioxidants did not have an effect on the activity of antioxidant enzymes. In conclusion, animal model of diabetes produced depressive-like behaviour and oxidative stress in the brain and periphery. Treatment with antioxidants could be a viable alternative to treat behavioural and biochemical alterations induced by diabetes.

Effect of subchronic administration of agomelatine on brain energy metabolism and oxidative stress parameters in rats.

AIMS: The aim of this study was to investigate the effect of subchronic administration of agomelatine on energy metabolism, oxidative stress markers and antioxidant defense in the brains of rats. METHODS: The animals received daily intraperitoneal injections of agomelatine (10, 30 or 50 mg/kg) or saline for 14 days. The prefrontal cortex, cerebellum, hippocampus, striatum and posterior cortex were analyzed. RESULTS: The findings showed that complex I was activated in the prefrontal cortex, cerebellum and striatum and inhibited in the posterior cortex at the 10-mg/kg dose, and inhibited in all brain areas analyzed at the 30-mg/kg and 50-mg/kg doses. Complex II was activated in the posterior cortex at the 50-mg/kg dose. Complex IV was inhibited in the striatum and posterior cortex at the 10-mg/kg dose, inhibited in the striatum at the 30-mg/kg dose and activated in the hippocampus at the 50-mg/kg dose. Creatine kinase activity was inhibited in the striatum at the 10-mg/kg and 30-mg/kg doses. Lipid peroxidation and protein carbonylation levels were not changed after the administration of agomelatine. Superoxide dismutase activity was increased in the striatum at the 10-mg/kg dose, and catalase activity was inhibited in the cerebellum at the 10-mg/kg dose and increased in the posterior cortex at the 30-mg/kg dose. CONCLUSIONS: Our results are consistent with other studies showing that some antidepressants may influence brain energy metabolism and oxidative stress parameters and expand knowledge about the effects of agomelatine in biochemical parameters in the brains of rats.

A single dose of S-ketamine induces long-term antidepressant effects and decreases oxidative stress in adulthood rats following maternal deprivation.

Ketamine, an antagonist of N-methyl-d-aspartate receptors, has produced rapid antidepressant effects in patients with depression, as well as in animal models. However, the extent and duration of the antidepressant effect over longer periods of time has not been considered. This study evaluated the effects of single dose of ketamine on behavior and oxidative stress, which is related to depression, in the brains of adult rats subjected to maternal deprivation. Deprived and nondeprived Wistar rats were divided into four groups nondeprived+saline; nondeprived+S-ketamine (15 mg/kg); deprived+saline; deprived+S-ketamine (15 mg/kg). A single dose of ketamine or saline was administrated during the adult phase, and 14 days later depressive-like behavior was assessed. In addition, lipid damage, protein damage, and antioxidant enzyme activities were evaluated in the rat brain. Maternal deprivation induces a depressive-like behavior, as verified by an increase in immobility and anhedonic behavior. However, a single dose of ketamine was able to reverse these alterations, showing long-term antidepressant effects. The brains of maternally deprived rats had an increase in protein oxidative damage and lipid peroxidation, but administration of a single dose of ketamine reversed this damage. The activities of antioxidant enzymes superoxide dismutase and catalase were reduced in the deprived rat brains. However, ketamine was also able to reverse these changes. In conclusion, these findings indicate that a single dose of ketamine is able to induce long-term antidepressant effects and protect against neural damage caused by oxidative stress in adulthood rats following maternal deprivation.

CD40-CD40 Ligand Pathway is a Major Component of Acute Neuroinflammation and Contributes to Long-term Cognitive Dysfunction after Sepsis.

Sepsis-associated encephalopathy (SAE) is associated with an increased rate of morbidity and mortality. It is not understood what the exact mechanism is for the brain dysfunction that occurs in septic patients, but brain inflammation and oxidative stress are a possible theory. Such events can occur through the alteration of molecules that perpetuate the inflammatory response. Thus, it is possible to postulate that CD40 may be involved in this process. The aim of this work is to evaluate the role of CD40-CD40L pathway activation in brain dysfunction associated with sepsis in an animal model. Microglia activation induces the upregulation of CD40-CD40L, both in vitro and in vivo. The inhibition of microglia activation decreases levels of CD40-CD40L in the brain and decreases brain inflammation, oxidative damage and blood brain barrier dysfunction. Despite this, anti-CD40 treatment does not improve mortality in this model. However, it is able to improve long-term cognitive impairment in sepsis survivors. In conclusion, there is a major involvement of the CD40-CD40L signaling pathway in long-term brain dysfunction in an animal model of sepsis.