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The present study aimed to investigate the effects of paradoxical sleep deprivation (PSD) on behavioral and oxidative stress parameters in the brain and serum of mice submitted to the animal model of hyperglycemia induced by alloxan, mimicking the main symptom of diabetes mellitus (DM). Adults C57BL/6 male and female mice received an injection of alloxan, and ten days later, the animals were submitted to the PSD for 36 h. The animals' behavioral parameters were evaluated in the open-field test. Oxidative stress parameters [Diacetyldichlorofluorescein (DCF), Thiobarbituric acid reactive substances (TBARS), Superoxide dismutase (SOD), and Glutathione] were assessed in the frontal cortex, hippocampus, striatum, and serum. The PSD increased the male and female mice locomotion, but the alloxan's pre-administration prevented the PSD-induced hyperactivity. In addition, the male mice receiving alloxan and submitted to the PSD had elevated latency time in the first quadrant and the number of fecal boli, demonstrating increased anxiety-like behavior. The HPA-axis was hyperactivating in male and female mice pre-administered alloxan and/or PSD-submitted animals. The oxidative stress parameters were also increased in the serum of the animals administered alloxan and/or sleep-deprived mice. Despite alloxan or PSD leading to behavioral or biochemical alterations, the one did not potentiate the other in mice. However, more studies are necessary to identify the link between sleep and hyperglycemia., Competing Interests: Competing Interests JQ received clinical research support from LivaNova; has speaker bureau membership with Myriad Neuroscience, Janssen Pharmaceuticals, and Abbvie; is consultant for Eurofarma; is stockholder at Instituto de Neurociencias Dr. Joao Quevedo; and receives copyrights from Artmed Editora, Artmed Panamericana, and Elsevier/Academic Press. All other authors have no conflicts of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The present study aims to evaluate the effects of haloperidol, an important first-generation antipsychotic, on the antioxidant system parameters in the brain of animals subjected to a model of schizophrenia induced by ketamine. Adult rats intraperitoneally received saline (1 mL/kg) or ketamine (25 mg/kg body weight) for 15 days, and saline or haloperidol (0.1 mg/kg body weight) via gavage once a day, between the 9th and 14th days. In the frontal cortex, hippocampus, and striatum, assessments of lipid (4-hydroxy-2-nonenal and 8-isoprostane levels) and protein (protein carbonyl content) oxidative damage were conducted. It was also measured the glutathione peroxidase and glutathione reductase activities in the same cerebral structures. Increases in the 4-hydroxy-2-nonenal and 8-isoprostane levels were detected in rats receiving haloperidol and ketamine. An increase in the carbonyl content was also observed in animals receiving ketamine, haloperidol, or a combination thereof. In animals receiving the antipsychotic, there was a decrease in the activity of the enzymes. Therefore, both ketamine and haloperidol induced oxidative damage. A possible energy dysfunction or a haloperidol effect targeting the glutathione enzymes, and then disrupting the redox homeostasis in neurons, could not be ruled out, although further studies are required to confirm or refute a direct interaction., (Copyright © 2021. Published by Elsevier Inc.)

Studies have suggested the involvement of oxidative stress in the physiopathology of bipolar disorder. Preclinical data have shown that PKC inhibitors may act as mood-stabilizing agents and protect the brain in animal models of mania. The present study aimed to evaluate the effects of Lithium (Li) or tamoxifen (TMX) on behavioral changes and oxidative stress parameters in an animal model of mania induced by ouabain (OUA). Wistar rats received a single intracerebroventricular (ICV) injection of OUA or artificial cerebrospinal fluid (ACSF). From the day following ICV injection, the rats were treated for seven days with intraperitoneal injections of saline, Li or TMX twice a day. On the 7th day after OUA injection, locomotor activity was measured using the open-field test, and the oxidative stress parameters were evaluated in the hippocampus and frontal cortex of rats. The results showed that OUA induced hyperactivity in rats, which is considered a manic-like behavior. Also, OUA increased lipid peroxidation and oxidative damage to proteins, as well as causing alterations to antioxidant enzymes in the frontal cortex and hippocampus of rats. The Li or TMX treatment reversed the manic-like behavior induced by OUA. Besides, Li, but not TMX, reversed the oxidative damage caused by OUA. These results suggest that the manic-like effects induced by OUA and the antimanic effects of TMX seem not to be related to the oxidative stress., (Copyright © 2019. Published by Elsevier Ltd.)

The present study aimed to evaluate the effects of resveratrol on behavior and oxidative stress parameters in the brain of rats submitted to the animal model of mania induced by m-AMPH. In the first model (reversal treatment), rats received intraperitoneal (i.p.) injection of saline or m-AMPH (1 mg/kg body weight) once a day for 14 days, and from the 8th to the 14th day, they were orally treated with water or resveratrol (15 mg/kg), once a day. In the second model (maintenance treatment), rats were orally pretreated with water or resveratrol (15 mg/kg) once a day, and from the 8th to the 14th day, they received saline or m-AMPH i.p., once a day. Locomotor and exploratory activities were assessed in the open-field test. Oxidative and nitrosative damage parameters to lipid and proteins were evaluated by TBARS, 4-HNE, carbonyl, and 3-nitrotyrosine in the brain submitted to the experimental models. m-AMPH administration increased the locomotor and exploratory activities; resveratrol was not able to reverse or prevent these manic-like behaviors. Additionally, m-AMPH increased the lipid and protein oxidation and nitrosylation in the frontal cortex, hippocampus, and striatum of rats. However, resveratrol prevented and reversed the oxidative and nitrosative damage to proteins and lipids in all cerebral areas assessed. Since oxidative stress plays an important role in BD pathophysiology, supplementation of resveratrol in BD patients could be regarded as a possible adjunctive treatment with mood stabilizers.

Background: Bipolar disorder (BD) and substance use disorders share common symptoms, such as behavioral sensitization. Amphetamine-induced behavioral sensitization can serve as an animal model of BD. Neurotrophic factors have an important role in BD pathophysiology. This study evaluated the effects of amphetamine sensitization on behavior and neurotrophic factor levels in the brains of rats., Methods: Wistar rats received daily intraperitoneal (i.p) injections of dextroamphetamine (d-AMPH) 2 mg/kg or saline for 14 days. After seven days of withdrawal, the animals were challenged with d-AMPH (0.5 mg/kg, i.p) and locomotor behavior was assessed. In a second protocol, rats were similarly treated with d-AMPH (2 mg/kg, i.p) for 14 days. After withdrawal, without d-AMPH challenge, depressive- and anxiety-like behaviors were evaluated through forced swimming test and elevated plus maze. Levels of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), neurotrophin 3 (NT-3), neurotrophin 4/5 (NT-4/5) and glial-derived neurotrophic factor (GDNF) were evaluated in the frontal cortex, hippocampus, and striatum., Results: D-AMPH for 14 days augmented locomotor sensitization to a lower dose of d-AMPH (0.5 mg/kg) after the withdrawal. d-AMPH withdrawal induced depressive- and anxious-like behaviors. BDNF, NGF, and GDNF levels were decreased, while NT-3 and NT-4 levels were increased in brains after d-AMPH sensitization., Limitations: Although d-AMPH induces manic-like behavior, the mechanisms underlying these effects can also be related to phenotypes of drug abuse., Conclusions: Together, vulnerability to mania-like behavior following d-AMPH challenge and extensive neurotrophic alterations, suggest amphetamine-induced behavioral sensitization is a good model of BD pathophysiology., (Copyright © 2018. Published by Elsevier B.V.)

Background: A periodontal lesion is a consequence of chronic inflammatory processes, itself triggered by a bacterial infection of the pulpal and endodontic microenvironment. Evidence suggests that periodontal lesion induction could alter inflammatory cytokines leading to behavior changes. These effects in the context of anxiety and depressive behavior have been not full investigated. We aimed to observe anxiety- and depressive-like behavioral in rodent subjected to periapical dental lesions., Methods: Pro-inflammatory cytokines levels also were investigated in the frontal cortex and hippocampus. Parameters related to hypothalamic-pituitary-adrenal (HPA) axis activation also were evaluated. Wistar rats were divided in groups: control/saline; control/imipramine; periapical lesion/saline; and periapical lesion/imipramine. Three weeks after induction of the periapical dental lesion, they were subjected to behavioral tests., Results: In the periapical lesion group was demonstrated anhedonic behavior and depressive-like behavior. In the elevated plus-maze test the periapical lesion group had an increase in the number of entries and spent more time in the closed arms. Imipramine treatment was able to reverse depressive- and anxiety-like behaviors. In the hippocampus and frontal cortex tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, and serum adrenocorticotropic hormone (ACTH) levels were higher in the periapical lesion group. However, rats treated with imipramine had lower IL-1β and ACTH levels., Conclusions: Our results revealed depressive- and anxiety-like behaviors following induction of a specific dental lesion. These effects could be associated to higher levels of brain pro-inflammatory cytokines and HPA axis changes. Antidepressants treatments could be an alternative to treat comorbidities associated to periodontal lesions., (Copyright © 2018 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier B.V. All rights reserved.)

Studies have suggested the involvement of inflammatory processes in the physiopathology of bipolar disorder. Preclinical evidences have shown that histone deacetylase inhibitors may act as mood-stabilizing agents and protect the brain in models of mania and depression. The aim of the present study was to evaluate the effects of sodium butyrate (SB) and valproate (VPA) on behavioral changes, histone deacetylase activity, and the levels of cytokines in an animal model of mania induced by dextroamphetamine (d-AMPH). Wistar rats were first given d-AMPH or saline (Sal) for a period of 14 days, and then, between the 8th and 14th days, the rats were treated with SB, VPA, or Sal. The activity of histone deacetylase and the levels of cytokines (interleukin (IL) IL-4, IL-6, and IL-10 and tumor necrosis factor-alpha (TNF-α)) were evaluated in the frontal cortex and striatum of the rats. The administration of d-AMPH increased the activity of histone deacetylase in the frontal cortex. Administration of SB or VPA decreased the levels of histone deacetylase activity in the frontal cortex and striatum of rats. SB per se increased the levels of cytokines in both of the brain structures evaluated. AMPH increased the levels of cytokines in both of the brain structures evaluated, and VPA reversed this alteration. The effects of SB on d-AMPH-induced cytokine alterations were dependent on the brain structure and the cytokine evaluated. Despite VPA and SB having a similar mechanism of action, both being histone deacetylase inhibitors, they showed different effects on the levels of cytokines. The present study reinforces the need for more research into histone deacetylase inhibitors being used as a possible target for new medications in the treatment of bipolar disorder.

Lithium (Li) is a mood-stabilizing drug used in the treatment of bipolar disorder (BD). Recently, preclinical studies have demonstrated the potential of tamoxifen (TMX) in the treatment of acute episodes of BD. However, the prolonged use of TMX for mood disorders treatment is controversial. In this study, we evaluated the effects of TMX or Li on cognitive behavior, as well as the levels of neurotrophic factors in the brain of male and female rats. Male and female Wistar rats received administrations of water (control group), TMX or Li via gavage for a period of 28days; the rats were then subjected to the open-field test (to evaluate spontaneous locomotion), and the novel object recognition and step-down inhibitory avoidance tests (to evaluate cognition). The levels of NGF, BDNF and GDNF were evaluated in the hippocampus and frontal cortex of the subject rats. No significant differences were observed in the open-field and inhibitory avoidance tests after drug administration in either the male or female rats. The administration of TMX, but not Li, decreased the recognition index of both the male and female rats in the object recognition test. The chronic administration of TMX decreased, whereas Li increased the levels of BDNF in the hippocampus of both the male and female rats. Tamoxifen decreased the levels of NGF in the hippocampus of female rats. In conclusion, it can be suggested that long-term treatments with TMX can lead to significant cognitive impairments by reducing the levels of neurotrophic factors in the brain of rats., (Copyright © 2017. Published by Elsevier Inc.)

Tyrosinemia type II is an inborn error of metabolism caused by a mutation in a gene encoding the enzyme tyrosine aminotransferase leading to an accumulation of tyrosine in the body, and is associated with neurologic and development difficulties in numerous patients. Because the accumulation of tyrosine promotes oxidative stress and DNA damage, the main aim of this study was to investigate the possible antioxidant and neuroprotective effects of omega-3 treatment in a chemically-induced model of Tyrosinemia type II in hippocampus, striatum and cerebral cortex of rats. Our results showed chronic administration of L-tyrosine increased the frequency and the index of DNA damage, as well as the 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels in the hippocampus, striatum and cerebral cortex. Moreover, omega-3 fatty acid treatment totally prevented increased DNA damage in the striatum and hippocampus, and partially prevented in the cerebral cortex, whereas the increase in 8-OHdG levels was totally prevented by omega-3 fatty acid treatment in hippocampus, striatum and cerebral cortex. In conclusion, the present study demonstrated that the main accumulating metabolite in Tyrosinemia type II induce DNA damage in hippocampus, striatum and cerebral cortex, possibly mediated by free radical production, and the supplementation with omega-3 fatty acids was able to prevent this damage, suggesting that could be involved in the prevention of oxidative damage to DNA in this disease. Thus, omega-3 fatty acids supplementation to Tyrosinemia type II patients may represent a new therapeutic approach and a possible adjuvant to the curren t treatment of this disease.

Objectives: The goal of the present study was to investigate the effects of lithium administration on behavior, oxidative stress parameters and cytokine levels in the periphery and brain of mice subjected to an animal model of mania induced by paradoxical sleep deprivation (PSD)., Methods: Male C57 mice were treated with saline or lithium for 7 days. The sleep deprivation protocol started on the 5th day during for the last 36 hours of the treatment period. Immediately after the sleep deprivation protocol, animals locomotor activity was evaluated and serum and brain samples was extracted to evaluation of corticosterone and adrenocorticotropic hormone circulating levels, oxidative stress parameters and citokynes levels., Results: The results showed that PSD induced hyperactivity in mice, which is considered a mania-like behavior. PSD increased lipid peroxidation and oxidative damage to DNA, as well as causing alterations to antioxidant enzymes in the frontal cortex, hippocampus and serum of mice. In addition, PSD increased the levels of cytokines in the brains of mice. Treatment with lithium prevented the mania-like behavior, oxidative damage and cytokine alterations induced by PSD., Conclusions: Improving our understanding of oxidative damage in biomolecules, antioxidant mechanisms and the inflammatory system - alterations presented in the animal models of mania - is important in helping us to improve our knowledge concerning the pathophysiology of BD, and the mechanisms of action employed by mood stabilizers., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Pneumococcal meningitis is a life-threatening infection of the central nervous system (CNS) with a high mortality rate. In addition to causing severe neurological sequelae infectious diseases of the CNS can play a significant role in the pathogenesis of neuropsychiatric disorders. In this study infant Wistar rats, postnatal day 11, received intracerebroventricular (i.c.v.) either artificial cerebrospinal fluid (CSF) or a Streptococcus pneumoniae suspension to a concentration of 1 × 10 6 colony-forming units (CFU). 18 h later animals received antibiotic treatment as usual during 7 days. On postnatal day 46, the animals received imipramine intraperitoneal (i.p.) or sterile NaCl during 14 days (postnatal days 46-60). Then, on postnatal days 59-60 we evaluated the consumption of sweet food (an index of anhedonia). On postnatal day 60 the animals were submitted to the forced swimming task. 60 min after this task the animals were decapitated and the blood was collected to evaluate adrenocorticotropic hormone (ACTH) and corticosterone. Immediately after blood collection the hippocampus was removed to evaluate brain-derived neurotropic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF). The meningitis group exhibited depressive-like behavior as evidenced by decreased sucrose intake and increased immobility time in the forced swimming task, and BDNF and GDNF decrease in the hippocampus. ACTH levels were increased in the blood. Imipramine treatment reversed depressive-like behaviors, re-established hippocampal BDNF and GDNF expression, and normalized ACTH levels in the blood. Here we demonstrate that meningitis during early life period can trigger depressive-like behavior in adult life of rats.

The current pathophysiological understanding of mechanisms leading to onset and progression of bipolar manic episodes remains limited. At the same time, available animal models for mania have limited face, construct, and predictive validities. Additionally, these models fail to encompass recent pathophysiological frameworks of bipolar disorder (BD), e.g. neuroprogression. Therefore, there is a need to search for novel preclinical models for mania that could comprehensively address these limitations. Herein we review the history, validity, and caveats of currently available animal models for mania. We also review new genetic models for mania, namely knockout mice for genes involved in neurotransmission, synapse formation, and intracellular signaling pathways. Furthermore, we review recent trends in preclinical models for mania that may aid in the comprehension of mechanisms underlying the neuroprogressive and recurring nature of BD. In conclusion, the validity of animal models for mania remains limited. Nevertheless, novel (e.g. genetic) animal models as well as adaptation of existing paradigms hold promise., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Several studies have suggested that alterations in brain-derived neurotrophic factor (BDNF) and increased oxidative stress have a central role in bipolar disorder (BD). Intracerebroventricular (ICV) injection of ouabain (OUA) in rats alters oxidative stress parameters and decreases BDNF levels in the brain. In this context, the present study aims to investigate the effects of BDNF ICV administration on BDNF levels and oxidative stress parameters in brains of rats submitted to animal model of mania induced by OUA. Wistar rats received an ICV injection of OUA, artificial cerebrospinal fluid (ACSF), OUA plus BDNF, or ACSF plus BDNF. Locomotor activity and risk-taking behavior in the rats were measured using the open-field test. In addition, we analyzed the BDNF levels and oxidative stress parameters (TBARS, Carbonyl, CAT, SOD, GR, and GPx) in the frontal cortex and hippocampus of rats. The BDNF was unable to reverse the ouabain-induced hyperactivity and risk-taking behavior. Nevertheless, BDNF treatment increased BDNF levels, modulated the antioxidant enzymes, and protected the OUA-induced oxidative damage in the brain of rats. These results suggest that BDNF alteration observed in BD patients may be associated with oxidative damage, both seen in this disorder.

Objectives: Several recent studies have suggested that the physiopathology of bipolar disorder (BD) is related to immune system alterations and inflammation. Lithium (Li) is a mood stabilizer that is considered the first-line treatment for this mood disorder. The goal of the present study was to investigate the effects of Li administration on behavior and cytokine levels [interleukin (IL)-1β, IL-4, IL-6, IL-10, and tumor necrosis factor-alpha (TNF-α)] in the periphery and brains of rats subjected to an animal model of mania induced by amphetamine (d-AMPH)., Methods: Male Wistar rats were treated with d-AMPH or saline (Sal) for 14 days; on Day 8 of treatment, the rats were administered Li or Sal for the final seven days. Cytokine (IL-1β, IL-4, IL-6, IL-10, and TNF-α) levels were evaluated in the cerebrospinal fluid (CSF), serum, frontal cortex, striatum, and hippocampus., Results: The present study showed that d-AMPH induced hyperactivity in rats (p < 0.001), and Li treatment reversed this behavioral alteration (p < 0.001). In addition, d-AMPH increased the levels of IL-4, IL-6, IL-10, and TNF-α in the frontal cortex (p < 0.001), striatum (p < 0.001), and serum (p < 0.001), and treatment with Li reversed these cytokine alterations (p < 0.001)., Conclusions: Li modulates peripheral and cerebral cytokine production in an animal model of mania induced by d-AMPH, suggesting that its action on the inflammatory system may contribute to its therapeutic efficacy., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The consumption of palatable high-fat and high-sugar foods have increased dramatically over the past years. Overconsumption of calorically dense food contributes to increasing rates of overweight and obesity that are associated with psychiatry disorders, in particular mood and anxiety disorders. This study evaluated the impact of palatable cafeteria diet (CAF) intake on cognitive and noncognitive behaviors, as well as identified factors related to these behaviors through an evaluation of brain neurotrophic factor (BDNF, NGF, and GDNF) levels in hippocampus of mice. Male Swiss mice received two different diets during 13 weeks: standard chow (STA) and highly CAF. Posteriorly, forced swimming test (FST), tail suspension test (TST), plus-maze test (PMT), open-field tests (OFT), and object recognition task (ORT) were utilized as behavioral tests. In addition, brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), and nerve growth factor (NGF) neurotrophins' levels were evaluated in hippocampus of mice. The results demonstrated that mice from the CAF group showed a decrease in the immobility time in the FST and TST. Besides, mice in the CAF group spent more time in the open arms of the PMT. No significant differences were observed in the cognitive behaviors, which were evaluated in the OFT and ORT. In addition, the CAF group showed that BDNF and NGF protein levels increased in the hippocampus of mice. In conclusion, our data suggest that the consumption of palatable high-fat and high-sugar foods induces antidepressant- and anxiolytic-like behaviors, which can be related with BDNF and NGF expression increases in hippocampus of mice in the CAF group.

Fenproporex is the second most commonly amphetamine-based anorectic consumed worldwide; this drug is rapidly converted into amphetamine, in vivo, and acts by increasing dopamine levels in the synaptic cleft. Considering that fenproporex effects on the central nervous system are still poorly known and that acetylcholinesterase is a regulatory enzyme which is involved in cholinergic synapses and may indirectly modulate the release of dopamine, the present study investigated the effects of acute administration of fenproporex on acetylcholinesterase activity in brain of young rats. Young male Wistar rats received a single injection of fenproporex (6.25, 12.5 or 25mg/kg i.p.) or vehicle (2% Tween 80). Two hours after the injection, the rats were killed by decapitation and the brain was removed for evaluation of acetylcholinesterase activity. Results showed that fenproporex administration increased acetylcholinesterase activity in the hippocampus and posterior cortex, whereas in the prefrontal cortex, striatum and cerebellum the enzyme activity was not altered. In conclusion, in the present study we demonstrated that acute administration of fenproporex exerts an effect in the cholinergic system causing an increase in the activity of acetylcholinesterase in a dose-dependent manner in the hippocampus and posterior cortex. Thus, we suggest that the imbalance in cholinergic homeostasis could be considered as an important pathophysiological mechanism underlying the brain damage observed in patients who use amphetamines such as fenproporex.

Bipolar disorder (BD) is a severe psychiatric disorder associated with social and functional impairment. Some studies have strongly suggested the involvement of oxidative stress in the pathophysiology of BD. Paradoxal sleep deprivation (PSD) in mice has been considered a good animal model of mania because it induces similar manic-like behavior, as well as producing the neurochemical alterations which have been observed in bipolar patients. Thus, the objective of the present study was to evaluate the effects of the antioxidant agent's n-acetylcysteine (Nac) and/or deferoxamine (DFX) on behavior and the oxidative stress parameters in the brains of mice submitted to the animal model of mania induced by PSD. The mice were treated for a period of seven days with saline solution (SAL), Nac, DFX or Nac plus DFX. The animals were subject to the PSD protocol for 36 h. Locomotor activity was then evaluated using the open-field test, and the oxidative stress parameters were subsequently evaluated in the hippocampus and frontal cortex of mice. The results showed PSD induced hyperactivity in mice, which is considered a manic-like behavior. In addition to this, PSD increased lipid peroxidation and oxidative damage to proteins, as well as causing alterations to antioxidant enzymes in the frontal cortex and hippocampus of mice. The Nac plus DFX adjunctive treatment prevented both the manic-like behavior and oxidative damage induced by PSD. Improving our understanding relating to oxidative damage in biomolecules, and the antioxidant mechanisms presented in the animal models of mania are important in helping to improve our knowledge concerning the pathophysiology and development of new therapeutical treatments for BD., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Studies have revealed alterations in mitochondrial complexes in the brains of bipolar patients. However, few studies have examined changes in the enzymes of the tricarboxylic acid cycle. Several preclinical studies have suggested that histone deacetylase inhibitors may have antimanic effects. The present study aims to investigate the effects of lithium, valproate and sodium butyrate, a histone deacetylase inhibitor, on the activity of tricarboxylic acid cycle enzymes in the brains of rats subjected to an animal model of mania induced by ouabain. Wistar rats received a single intracerebroventricular injection of ouabain or cerebrospinal fluid. Starting on the day following the intracerebroventricular injection, the rats were treated for 7days with intraperitoneal injections of saline, lithium, valproate or sodium butyrate. Risk-taking behavior, locomotor and exploratory activities were measured using the open-field test. Citrate synthase, succinate dehydrogenase, and malate dehydrogenase were examined in the frontal cortex and hippocampus. All treatments reversed ouabain-related risk-taking behavior and hyperactivity in the open-field test. Ouabain inhibited tricarboxylic acid cycle enzymes in the brain, and valproate and sodium butyrate but not lithium reversed this ouabain-induced dysfunction. Thus, protecting the tricarboxylic acid cycle may contribute to the therapeutic effects of histone deacetylase inhibitors., (Copyright © 2014 Elsevier Inc. All rights reserved.)

The neurobiological basis of bipolar disorder (BD) remains unknown; nevertheless, mitochondrial dysfunction has been identified in this disorder. Inactivation of any step in the tricarboxylic acid (TCA) cycle can impair mitochondrial ATP production. There is recent evidence indicating that PKC is an important therapeutic target for bipolar disorder. Therefore, we evaluated the effects of tamoxifen (TMX--a PKC inhibitor) on the activities of enzymes in the TCA cycle of rat brains subjected to an animal model of mania induced by amphetamine. In the reversal treatment, Wistar rats were first treated with d-AMPH or saliratsne (Sal) for 14 days. Thereafter, between days 8 and 14, the rats were administered TMX or Sal. The citrate synthase, succinate dehydrogenase, and malate dehydrogenase were evaluated in the frontal cortex, hippocampus, and striatum. The d-AMPH administration inhibited TCA cycle enzymes activity in all analyzed structures, and TMX reversed d-AMPH-induced dysfunction. In addition, we observed a negative correlation between d-AMPH-induced hyperactivity and the activity of these enzymes in the rat's brain. These findings suggested that TCA cycle enzymes inhibition can be an important link for the mitochondrial dysfunction seen in BD, and TMX exert protective effects against the d-AMPH-induced TCA cycle enzymes dysfunction., (© 2013 Published by Elsevier Ireland Ltd.)

Objective: Cognitive deficits in schizophrenia play a crucial role in its clinical manifestation and seem to be related to changes in the cholinergic system, specifically the action of acetylcholinesterase (AChE). Considering this context, the aim of this study was to evaluate the chronic effects of ketamine in the activity of AChE, as well as in behavioural parameters involving learning and memory., Methods: The ketamine was administered for 7 days. A duration of 24 h after the last injection, the animals were submitted to behavioural tests. The activity of AChE in prefrontal cortex, hippocampus and striatum was measured at different times after the last injection (1, 3, 6 and 24 h)., Results: The results indicate that ketamine did not affect locomotor activity and stereotypical movements. However, a cognitive deficit was observed in these animals by examining their behaviour in inhibitory avoidance. In addition, an increase in AChE activity was observed in all structures analysed 1, 3 and 6 h after the last injection. Differently, serum activity of AChE was similar between groups., Conclusion: Chronic administration of ketamine in an animal model of schizophrenia generates increased AChE levels in different brain tissues of rats that lead to cognitive deficits. Therefore, further studies are needed to elucidate the complex mechanisms associated with schizophrenia.

The effects of modafinil (MD) on behavioral and oxidative damage to protein and lipid in the brain of rats were evaluated. Wistar rats were given a single administration by gavage of water or MD (75, 150, or 300 mg/kg). Behavioral parameters were evaluated in open-field apparatus 1, 2, and 3 h after drug administration. Thiobarbituric acid reactive substances (TBARS) and protein carbonyl formation were measured in the brain. MD increased locomotor activity at the highest dose 1 and 3 h after administration. MD administration at the dose of 300 mg/kg increased visits to the center of open-field 1 h after administration; however, 3 h after administration, all administered doses of MD increased visits to the open-field center. MD 300 mg/kg increased lipid damage in the amygdala, hippocampus, and striatum. Besides, MD increased protein damage in the prefrontal cortex, amygdala, and hippocampus; however, this effect varies depending on the dose administered. In contrast, the administration of MD 75 and 300 mg/kg decreased the protein damage in the striatum. This study demonstrated that the MD administration induces behavioral changes, which was depending on the dose used. In addition, the effects of MD on oxidative damage parameters seemed to be in specific brain region and doses.

There is increasing interest in the possibility that mitochondrial impairment may play an important role in bipolar disorder (BD). The Krebs cycle is the central point of oxidative metabolism, providing carbon for biosynthesis and reducing agents for generation of ATP. Recently, studies have suggested that histone deacetylase (HDAC) inhibitors may have antimanic effects. The present study aims to investigate the effects of sodium butyrate (SB), a HDAC inhibitor, on Krebs cycle enzymes activity in the brain of rats subjected to an animal model of mania induced by D-amphetamine (D-AMPH). Wistar rats were first given D-AMPH or saline (Sal) for 14 days, and then, between days 8 and 14, rats were treated with SB or Sal. The citrate synthase (CS), succinate dehydrogenase (SDH), and malate dehydrogenase (MDH) were evaluated in the prefrontal cortex, hippocampus, and striatum of rats. The D-AMPH administration inhibited Krebs cycle enzymes activity in all analyzed brain structures and SB reversed D-AMPH-induced dysfunction analyzed in all brain regions. These findings suggest that Krebs cycle enzymes' inhibition can be an important link for the mitochondrial dysfunction seen in BD and SB exerts protective effects against the D-AMPH-induced Krebs cycle enzymes' dysfunction.

Objective: To investigate the effects of cannabidiol (CBD) on mitochondrial complex and creatine kinase (CK) activity in the rat brain using spectrophotometry., Method: Male adult Wistar rats were given intraperitoneal injections of vehicle or CBD (15, 30, or 60 mg/kg) in an acute (single dose) or chronic (once daily for 14 consecutive days) regimen. The activities of mitochondrial complexes and CK were measured in the hippocampus, striatum, and prefrontal cortex., Results: Both acute and chronic injection of CBD increased the activity of the mitochondrial complexes (I, II, II-III, and IV) and CK in the rat brain., Conclusions: Considering that metabolism impairment is certainly involved in the pathophysiology of mood disorders, the modulation of energy metabolism (e.g., by increased mitochondrial complex and CK activity) by CBD could be an important mechanism implicated in the action of CBD.

The present study aims to investigate the effects of mood stabilizers, lithium (Li) and valproate (VPA), on acetylcholinesterase (AChE) activity in the brains of rats subjected to an animal model of mania induced by D-amphetamine (D-AMPH). In the reversal treatment, Wistar rats were first given D-AMPH or saline (Sal) for 14 days. Between days 8 and 14, the rats were treated with Li, VPA, or Sal. In the prevention treatment, rats were pretreated with Li, VPA, or Sal. AChE activity was measured in the brain structures (prefrontal cortex, hippocampus, and striatum). Li, alone in reversion and prevention treatments, increased AChE activity in the brains of rats. VPA, alone in prevention treatment, increased AChE activity in all brain regions evaluated; in the reversion, only in the prefrontal. However, D-AMPH decreased activity of AChE in the striatum of rats in both the reversion and prevention treatments. VPA was able to revert and prevent this AChE activity alteration in the rat striatum. Our findings further support the notion that the mechanisms of mood stabilizers also involve changes in AChE activity, thus reinforcing the need for more studies to better characterize the role of acetylcholine in bipolar disorder., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Fenproporex is an amphetamine-based anorectic and it is rapidly converted in vivo into amphetamine. It elevates the levels of extracellular dopamine in the brain. Acetylcholinesterase is a regulatory enzyme which is involved in cholinergic synapses and may indirectly modulate the release of dopamine. Thus, we investigated whether the effects of chronic administration of fenproporex in adult rats alters acquisition and retention of avoidance memory and acetylcholinesterase activity. Adult male Wistar rats received repeated (14 days) intraperitoneal injection of vehicle or fenproporex (6.25, 12.5 or 25 mg/kg i.p.). For behavioral assessment, animals were submitted to inhibitory avoidance (IA) tasks and continuous multiple trials step-down inhibitory avoidance (CMIA). Acetylcholinesterase activity was measured in the prefrontal cortex, hippocampus, hypothalamus and striatum. The administration of fenproporex (6.25, 12.5 and 25 mg/kg) did not induce impairment in short and long-term IA or CMIA retention memory in rats. In addition, longer periods of exposure to fenproporex administration decreased acetylcholinesterase activity in prefrontal cortex and striatum of rats, but no alteration was verified in the hippocampus and hypothalamus. In conclusion, the present study showed that chronic fenproporex administration decreased acetylcholinesterase activity in the rat brain. However, longer periods of exposure to fenproporex did not produce impairment in short and long-term IA or CMIA retention memory in rats.

Studies have demonstrated that AMPHs produce long-term damage to the brain dopaminergic, serotoninergic and glutamatergic regions. Prefrontal cortex, amygdala, hippocampus and striatum appear to be involved in the toxicity and behavioral changes induced by AMPHs. A single dose of AMPH causes mitochondrial dysfunction and oxidative stress in rat brain. The goal of the present study was thus to investigate the potency of two amphetamines, dextroamphetamine (d-AMPH) and methamphetamine (m-AMPH), on the behavior and energetic dysfunction in the brain of rats. d-AMPH and m-AMPH increased the crossing and rearing behaviors. The numbers of visits to the center were increased by d-AMPH and m-AMPH only at 2mg/kg. Likewise, at a high dose (2 mg/kg), the injection of m-AMPH increased the amount of sniffing. The AMPHs significantly decreased the activities of Krebs cycle enzymes (citrate synthase and succinate dehydrogenase) and mitochondrial respiratory chain complexes (I-IV); nevertheless, this effect varied depending on the brain region evaluated. In summary, this study demonstrated that at high doses, m-AMPH, increased stereotyped (sniffing) behavior in rats, but d-AMPH did not. However, this study shows that d-AMPH and m-AMPH seem to have similar effects on the brains energetic metabolism., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

In this study methamphetamine (m-AMPH) and dextroamphetamine (d-AMPH) were compared to determine the potency of the two drugs on behavior and oxidative damage in brain of rats. Male adult Wistar rats were given single (acute administration) or repeated (chronic administration, 14 days) intraperitoneal injections of saline (0.9% NaCl), d-AMPH (2 mg/kg) or m-AMPH (0.25, 0.5, 1 or 2 mg/kg). Locomotor activity was evaluated in open-field apparatus 2 h after the last drug injection. Additionally, thiobarbituric acid reactive substances (TBARS) and protein carbonyl formation were measured in the prefrontal cortex, amygdala, hippocampus and striatum. In both experiments, d-AMPH and m-AMPH (all doses administered) increased the locomotor activity of animals, meantime, no significant difference between d-AMPH and m-AMPH was observed. d-AMPH and m-AMPH increased lipid and protein damage, but m-AMPH was more potent than d-AMPH, however, this effect varies depending on the brain region and the experimental protocol. The results of this study show that d-AMPH and m-AMPH have similar behavioral effects, which previous studies had already reported. On the other hand, this study demonstrated that the m-AMPH induces oxidative damage greater than d-AMPH, showing neurochemical differences previously unknown.

Obesity is a chronic disease of multiple etiologies, including genetic, metabolic, environmental, social, and other factors. Pharmaceutical strategies in the treatment of obesity include drugs that regulate food intake, thermo genesis, fat absorption, and fat metabolism. Fenproporex is the second most commonly consumed amphetamine-based anorectic worldwide; this drug is rapidly converted in vivo into amphetamine. Studies suggest that amphetamine induces neurotoxicity through generation of free radicals and mitochondrial apoptotic pathway by cytochrome c release, accompanied by a decrease of mitochondrial membrane potential. Mitochondria are intracellular organelles that play a crucial role in ATP production. Thus, in the present study we evaluated the activities of some enzymes of Krebs cycle, mitochondrial respiratory chain complexes and creatine kinase in the brain of young rats submitted to acute and chronic administration of fenproporex. In the acute administration, the animals received a single injection of fenproporex (6.25, 12.5 or 25 mg/kg i.p.) or tween. In the chronic administration, the animals received a single injection daily for 14 days of fenproporex (6.25, 12.5 or 25 mg/Kg i.p.). Two hours after the last injection, the rats were sacrificed by decapitation and the brain was removed for evaluation of biochemical parameters. Our results showed that the activities of citrate synthase, malate dehydrogenase and succinate dehydrogenase were increased by acute and chronic administration of fenproporex. Complexes I, II, II-III and IV and creatine kinase activities were also increased after acute and chronic administration of the drug. Our results are consistent with others reports that showed that some psychostimulant drugs increased brain energy metabolism in young rats., (Copyright © 2011 ISDN. Published by Elsevier Ltd. All rights reserved.)

The present study investigated the effect of the histone deacetylase inhibitor, sodium butyrate (SB), on locomotor behavior and on mitochondrial respiratory-chain complexes activity in the brain of rats subjected to an animal model of mania induced by d-amphetamine (d-AMPH). In the reversal treatment, Wistar rats were first treated with d-AMPH or saline (Sal) for 14 days. Thereafter, between days 8 and 14, rats were administered SB or Sal. In the prevention treatment, rats were treated with SB or Sal for 14 days and received d-AMPH or Sal between days 8 and 14. The d-AMPH treatment increased locomotor behavior in Sal-treated rats under reversion and prevention treatment, and SB reversed and prevented d-AMPH-related hyperactivity. Moreover, d-AMPH decreased the activity of mitochondrial respiratory-chain complexes in Sal-treated rats in the prefrontal cortex, hippocampus, striatum, and amygdala in both experiments, and SB was able to reverse and prevent this impairment. The present study suggests that the mechanism of action of SB involves induction of mitochondrial function in parallel with behavioral changes, reinforcing the need for more studies on histone deacetylase inhibitors as a possible target for new medications for bipolar disorder treatment.

Bipolar disorder (BD) is a devastating major mental illness associated with high rates of suicide and work loss. There is an emerging body of data suggesting that bipolar disorder is associated with mitochondrial dysfunction. In this context, the present study aims to investigate the effects of mood stabilizers lithium (Li) and valproate (VPT) on mitochondrial respiratory chain activity in brain of rats undergoing treatment with the pro-manic agent d-AMPH d-amphetamine (d-AMPH). In the reversal treatment, Wistar rats were first given d-AMPH or saline for 14 days, and then, between days 8 and 14, rats were treated with Li, VPA or saline (Sal). In the prevention treatment, rats were pretreated with Li, VPA or Sal. Locomotor behavior was assessed using the open-field task and mitochondrial chain activity complexes I, II, III and IV were measured in brain structures (hippocampus, striatum and prefrontal). Li and VPA reversed and prevented d-AMPH-induced hyperactivity. In both experiments, d-AMPH inhibited mitochondrial respiratory chain activity in all analyzed structures. In the reversal treatment, VPA reversed d-AMPH-induced dysfunction in all brain regions analyzed. In the prevention experiment, the effects of Li and VPA on d-AMPH-induced mitochondrial dysfunction were dependent on the brain region analyzed. These findings suggested that dopamine can be an important link for the mitochondrial dysfunction seen in BD and, Li and VPA exert protective effects against this d-AMPH-induced mitochondrial dysfunction, but this effect varies depending on the brain region and the treatment regimen., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Step-down inhibitory avoidance is usually acquired in one single trial, which makes it ideal for studying processes initiated by training, uncontaminated by prior or further trials, rehearsals, or retrievals. Neuronal calcium sensor 1 (NCS-1) is a dopamine receptor interacting protein that has been associated with associative learning and memory. We evaluated whether inhibitory avoidance can alter NCS-1 levels in rat brain. We focused our analysis on the striatum, entorhinal cortex, hippocampus and prefrontal cortex. Protein levels were measured using immunoblotting normalized by actin levels. Our results indicate that NCS-1 levels are not altered after step-down inhibitory avoidance in rat striatum, entorhinal cortex, hippocampus and prefrontal cortex. The link between protein interactions and the varied physiological roles of NCS-1 still remains to be fully established. Furthermore, other experiments are needed to shed more light on the role of NCS-1 and other mechanisms linked to signaling pathways related to inhibitory avoidance task., (Copyright 2010 Elsevier Inc. All rights reserved.)

Intracerebroventricular (ICV) injection of ouabain (a potent Na(+)/K(+)-ATPase inhibitor) in rats resulted in manic-like effects. There is an emerging body of data indicating that major neuropsychiatric disorders, such as bipolar disorder and schizophrenia, are associated with increased oxidative stress. In this study, we investigated the effects of ICV ouabain injection on oxidative stress parameters in total tissue of rat brain. Our findings demonstrated that ICV injection increased thiobarbituric acid reactive species levels and protein carbonyl generation in the prefrontal cortex and hippocampus of rats. Moreover, the activity of the antioxidants enzymes catalase and superoxide dismutase was altered in several areas of the rat brain and cerebrospinal fluid of ICV ouabain-subjected rats. These results showed that Na(+)/K(+)-ATPase inhibition can lead to oxidative stress in the brain of rats.

Previous studies have suggested that bipolar disorder may be associated with oxidative stress. Administration of D: -amphetamine (AMPH) has been put forward as an animal model of mania, and has shown to increase oxidative stress parameters in the rat brain. Thus, we have used the gastrin-releasing peptide receptor antagonist [D-Tpi(6)Leu(13)psi (CH(2)NH)-Leu(14)] bombesin (RC-3095) as a pharmacological tool to investigate the role of bombesin-like peptides in the redox balance in the hippocampus and cortex of rats treated with AMPH. Rats were given a single 10 ml/kg intraperitoneal (i.p.) injection of saline (SAL) or RC-3095 (0.1, 1.0 or 10.0 mg/kg) followed by an i.p. injection of SAL or amphetamine (AMPH 2.0 mg/kg) 30 min later. Locomotor activity was evaluated 2 h after the last drug injection. The thiobarbituric acid reactive substances (TBARS), protein carbonyl formation, superoxide dismutase and catalase (CAT) activity were measured in hippocampus, striatum and cortex as markers of oxidative stress. The results show that RC-3095 blocks AMPH-induced hyperlocomotion. Moreover, specific doses of RC-3095 alone increased the levels of oxidative stress in the dorsal hippocampus and cortex. However, when AMPH was subsequently administrated, RC-3095 decreased TBARS and protein carbonyls formation and increased the superoxide dismutase and CAT activity in the hippocampus, striatum and cortex. The effects of GRPR antagonist seemed to be region and dose specific. In conclusion, the results suggest that GRPR antagonists might display antioxidant properties in the brain.

The prescription of methylphenidate (MPH) has dramatically increased in this decade for attention deficit hyperactivity disorder (ADHD) treatment. The action mechanism of MPH is not completely understood and studies have been demonstrated that MPH can lead to neurochemical adaptations. Superoxide radical anion is not very reactive per se. However, severe species derived from superoxide radical anion mediate most of its toxicity. In this study, the superoxide level in submitochondrial particles was evaluated in response to treatment with MPH in the age-dependent manner in rats. MPH was administrated acutely or chronically at doses of 1, 2 or 10 mg/kg i.p. The results showed that the acute administration of MPH in all doses in young rats increased the production of superoxide in the cerebellum and only in the high dose (10mg/kg) in the hippocampus, while chronic treatment had no effect. However, acute treatment in adult rats had no effect on production of superoxide, but chronic treatment decreased the production of superoxide in the cerebellum at the lower doses. Our data suggest that the MPH treatment can influence on production of superoxide in some brain areas, but this effect depends on age of animals and treatment regime with MPH.

Objective: Clinical findings suggest that ketamine may be used for the treatment of major depression. The present study aimed to compare behavioral effects and brain Creatine kinase activity in specific brain regions after administration of ketamine and imipramine in rats., Method: Rats were acutely given ketamine or imipramine and antidepressant-like activity was assessed by the forced swimming test; Creatine kinase activity was measured in different regions of the brain., Results: The results showed that ketamine (10 and 15mg/kg) and imipramine (20 and 30mg/kg) reduced immobility time when compared to saline group. We also observed that ketamine (10 and 15mg/kg) and imipramine (20 and 30mg/kg) increased Creatine kinase activity in striatum and cerebral cortex. Ketamine at the highest dose (15mg/kg) and imipramine (20 and 30mg/kg) increased Creatine kinase activity in cerebellum and prefrontal cortex. On the other hand, hippocampus was not affected., Conclusion: Considering that metabolism impairment is probably involved in the pathophysiology of depressive disorders, the modulation of energy metabolism (like increase in Creatine kinase activity) by antidepressants could be an important mechanism of action of these drugs.

Major depression is a common, serious and recurrent disorder, characterized by symptoms at the psychological, behavioral and physiological levels. Recent studies have suggested that reactive oxygen species (ROS) may play a role in the pathophysiology of bipolar disorder. The chronic mild stress (CMS) rat model has been used as an animal model of depression, since it induces some symptoms of a major depressive episode in humans (i.e. anhedonia). We investigated behavioral, physiological and neurochemical aspects of rats exposed for 40 days to CMS. Sweet food consumption, locomotor activity and body weight were assessed in stressed and control rats. We also investigated the potential involvement of ROS in the CMS model. Superoxide generation in submitochondrial particles from the rat hippocampus, prefrontal cortex and cortex was measured through superoxide-dependent oxidation of epinephrine to adrenochrome in a submitochondrial extract. We report that sweet food intake was reduced in rats subjected to CMS compared to controls. Further, CMS animals failed to gain body weight compared with non-stressed rats. Locomotor activity was not affected in stressed rats. An increase in superoxide production was detected in all brain structures analyzed. However, thiobarbituric acid reactive substances were increased only in cortex. In conclusion, these observations support the view that the CMS model of depression mimics alterations observed in depressed patients. The model affords a useful system in which to test the hypothesis that altered brain energy metabolism is associated with neuropsychiatric disorders.

Major depression is characterized for symptoms at the psychological, behavioral and physiological levels. The chronic mild stress model has been used as an animal model of depression. The consumption of sweet food, locomotor activity, body weight, lipid and protein oxidation levels and superoxide dismutase and catalase activities in the rat hippocampus, prefrontal cortex and cortex were assessed in rats exposed to chronic mild stress. Our findings demonstrated a decrease on sweet food intake, no effect on locomotor activity, lack of body weight gain, increase in protein (prefrontal, hippocampus, striatum and cortex) and lipidic peroxidation (cerebellum and striatum), and an increase in catalase (cerebellum, hippocampus, striatum, cortex) and a decrease in superoxide dismutase activity (prefrontal, hippocampus, striatum and cortex) in stressed rats. In conclusion, our results support the idea that stress produces oxidants and an imbalance between superoxide dismutase and catalase activities that contributes to stress-related diseases, such as depression.

Dopamine may alter the phosphorylation state of DARPP-32 that plays a central role in the dopaminergic neurons biology. Studies have shown that DARPP-32/protein phosphatase 1 cascade is a major target for psychostimulants drugs. Methylphenidate is a psychostimulant that acts blocking the dopamine transporter has been used as an effective treatment for Attention Deficit Hyperactivity Disorder. We investigated if methylphenidate could alter DARPP-32 expression in five brain regions (striatum, hippocampus, prefrontal cortex, cortex and cerebellum) in young and adult rats. Our results showed that methylphenidate treatment is able to alter DARPP-32 expression in rat brain. Acute methylphenidate treatment has reduced hippocampal DARPP-32 protein levels in old rats, while chronic methylphenidate treatment has decreased them in old rat hippocampus and young rat cerebellum. It was found an increased cortical expression after chronic methylphenidate administration in old rats. Our results provide the first experimental demonstration that methylphenidate induces changes in total DARPP-32 expression that are posology- and age-related in some rat brain areas, although further studies are needed to shed more light on the mechanisms behind these findings.

There is evidence pointing to dysfunction at the mitochondrial level as an important target for the understanding of the pathophysiology of bipolar disorder (BD). We assessed creatine kinase (CK) activity in rats submitted to an animal model of mania which included the use of lithium and valproate. In the acute treatment, amphetamine (AMPH) or saline was administered to rats for 14 days, and between day 8 and 14, rats were treated with either lithium, valproate or saline. In the maintenance treatment, rats were pretreated with lithium, valproate or saline, and between day 8 and 14, AMPH or saline were administered. In both experiments, locomotor activity was assessed by open-field test and CK activity was evaluated in hippocampus, striatum, cerebellum, whole cortex and prefrontal cortex. Our results showed that mood stabilizers reversed AMPH-induced behavioral effects. Moreover, AMPH (acute treatment) inhibited CK activity in hippocampus, striatum and cortex, but not in cerebellum and prefrontal cortex, and administration of lithium or valproate did not reverse the enzyme inhibition. In the maintenance treatment, AMPH decreased CK activity in saline-pretreated rats in hippocampus, striatum and cortex, but not in cerebellum and prefrontal cortex. AMPH administration in lithium- or valproate-pretreated animals decreased CK activity in hippocampus, striatum and cortex. Our results showed that AMPH inhibited CK activity and that mood stabilizers were not able to reverse and/or prevent the enzyme inhibition. These findings reinforce the hypothesis that mitochondrial dysfunction plays an important role in the pathophysiology of BD.

Background: Methylphenidate (MPH) is a widely prescribed psychostimulant for the treatment of attention-deficit hyperactivity disorder (ADHD). Recently, some studies have addressed the genotoxic potential of the MPH, but the results have been contradictory. Hence, the present study aimed to investigate the index of cerebral and peripheral DNA damage in young and adult rats after acute and chronic MPH exposure., Methods: We used (1) single cell gel electrophoresis (Comet assay) to measure early DNA damage in hippocampus, striatum and total blood, and (2) micronucleus test in total blood samples., Results: Our results showed that MPH increased the peripheral index of early DNA damage in young and adult rats, which was more pronounced with chronic treatment and in the striatum compared to the hippocampus. Neither acute nor chronic MPH treatment increased micronucleus frequency in young or in adult rats. Peripheral DNA damage was positively correlated with striatal DNA damage., Conclusion: These results suggest that MPH may induce central and peripheral early DNA damage, but this early damage may be repaired.

Freitas TP, Rezin GT, Fraga DB, Moretti M, Vieira JS, Gomes LM, Borges LS, Valvassori SS, Quevedo J, Streck EL. Mitochondrial respiratory chain activity in an animal model of mania induced by ouabain. Bipolar disorder (BD) is a mental illness associated with higher rates of suicide. The present study aims to investigate the brain mitochondrial respiratory chain activity in an animal model of mania induced by ouabain. Adult male Wistar rats received a single intracerebroventricular administration of ouabain (10 and 10 M) or vehicle. Locomotor activity was measured using the open field test. Mitochondrial respiratory chain activity was measured in the brain of rats 1 h and 7 days after ouabain administration. Our results showed that spontaneous locomotion was increased 1 h and 7 days after ouabain administration. Complexes I, III and IV activities were increased in the prefrontal cortex, hippocampus and striatum immediately after the administration of ouabain, at the concentration of 10 and 10 M. Moreover, complex II activity was increased only in the prefrontal cortex at the concentration of 10 M. On the other hand, no significant alterations were observed in complex I activity 7 days after ouabain administration. However, an increase in complexes II, III and IV activities was observed only in the prefrontal cortex at the concentration of 10 M. Our findings suggest an increase in the activities of mitochondrial respiratory chain in this model of mania. A possible explanation is that these findings occur as a rebound effect trying to compensate for a decrease of ATP deprivation in BD. The present findings suggest that this model may present good face validity and a limitation in construct validity. [ABSTRACT FROM AUTHOR]