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Introduction: Obesity is defined as an excess of accumulation of fat that can be harmful to health. Storage of excess fat in the adipose tissue triggers an inflammatory process, which makes obesity a low-grade chronic inflammatory disease. Obesity is considered a complex and multifactorial disease; hence, no intervention strategy appears to be an ideal treatment for all individuals. Therefore, new therapeutic alternatives are often studied for the treatment of this disease. Currently, herbal medicines are gaining ground in the treatment of obesity and its comorbidities. In this context, much attention is being paid to Cannabis sativa derivatives, and their therapeutic functions are being widely studied, including in treating obesity. Objective: Highlight the pharmacological properties of Δ9-tetrahydrocannabivarin (THCV), Δ9-tetrahydrocannabidinol (THC), and cannabidiol (CBD), the predominant isolated components of Cannabis sativa, as well as its therapeutic potential in the treatment of obesity. Methods: This is a narrative review that shows the existing scientific evidence on the clinical application of Cannabis sativa as a possible treatment for obesity. Data collection was performed in the PubMed electronic database. The following word combinations were used: Cannabis and obesity, Cannabis sativa and obesity, THCV and obesity, THC and obesity, CBD and obesity, and Cannabis sativa and inflammation. Results: Evidence shows that Cannabis sativa derivatives have therapeutic potential due to their anti-inflammatory properties. In addition, people who use cannabis have a lower body mass index than those who do not, making the plant an option to reduce and reverse inflammation and comorbidities in obesity. Conclusion: It is concluded that phytocannabinoids derived from Cannabis sativa have therapeutic potential due to its anti-inflammatory, antioxidant, and neuroprotective properties, making the plant a study option to reduce and reverse inflammation and comorbidities associated with obesity.

This study evaluated the effects of omega-3 polyunsaturated fatty acids (PUFAs) on oxidative stress and energy metabolism parameters in the visceral fat of a high-fat-diet induced obesity model. Energy intake, body mass, and visceral fat mass were also evaluated. Male Swiss mice received either a control diet (control group) or a high-fat diet (obese group) for 6 weeks. After this period, the groups were divided into control + saline, control + omega-3, obese + saline, and obese + omega-3, and to these groups 400 mg·(kg body mass)−1·day−1of fish oil (or saline) was administered orally, for 4 weeks. Energy intake and body mass were monitored throughout the experiment. In the 10th week, the animals were euthanized and the visceral fat (mesenteric) was removed. Treatment with omega-3 PUFAs did not affect energy intake or body mass, but it did reduced visceral fat mass. In visceral fat, omega-3 PUFAs reduced oxidative damage and alleviated changes to the antioxidant defense system and the Krebs cycle. The mitochondrial respiratory chain was neither altered by obesity nor by omega-3 PUFAs. In conclusion, omega-3 PUFAs have beneficial effects on the visceral fat of obese mice because they mitigate changes caused by the consumption of a high-fat diet.

Postoperative cognitive dysfunction (POCD) is defined by cognitive impairment determined by neuropsychological tests from before to after surgery. Several mechanisms have been proposed in this bidirectional communication between the immune system and the brain after surgery. We aimed at understanding the mechanisms underlying POCD elderly rats in an experimental tibial fracture model. Elderly male Wistar rats were subjected to tibial fracture (TF) model. Control (sham) and fracture (TF) groups were followed to determine nitrite/nitrate concentration; oxidative damage to lipids and proteins; the activity of antioxidant enzymes (superoxide dismutase-SOD and catalase-CAT), mitochondrial respiratory chain enzymes, and creatine kinase (CK); and BDNF levels in the hippocampus and prefrontal cortex (at 24 h and at seven days) and cognitive function through habituation to the open field task and novel object recognition task (only at seven days). TF group presented increased concentration of nitrite/nitrate, hippocampal lipid peroxidation at seven days, protein oxidative damage in the prefrontal cortex and hippocampus at 24 h, decreased antioxidant activity in both structures on the first postoperative day and compromised function of the mitochondrial respiratory chain complexes as well as the CK enzyme. In addition, the levels of BDNF were reduced and memory function was impaired in the TF group. In conclusion, elderly rats submitted to an experimental model of tibial fracture displayed memory impairment accompanied by an increase in oxidative stress, mitochondrial dysfunction and reduced neurotrophin level.

At the end of 2019, a new disease with pandemic potential appeared in China. It was a novel coronavirus called coronavirus disease 2019 (COVID-19). Later, in the first quarter of 2020, the World Health Organization declared the outbreak of this disease a pandemic. Elderly people, people with comorbidities, and health care professionals are more vulnerable to COVID-19. Obesity has been growing exponentially worldwide, affecting several age groups. It is a morbidity that is associated with genetic, epigenetic, environment factors and/or interaction between them. Obesity is associated with the development of several diseases including diabetes mellitus, mainly type 2. Diabetes affects a significant portion of the global population. Obesity and diabetes are among the main risk factors for the development of severe symptoms of COVID-19, and individuals with these conditions constitute a risk group. Based on a literature review on obesity in people with diabetes in the framework of the COVID-19 pandemic, this study presents updated important considerations and care to be taken with this population.

Sepsis-associated encephalopathy is a serious consequence of sepsis, triggered by the host response against an infectious agent, that can lead to brain damage and cognitive impairment. Several mechanisms have been proposed in this bidirectional communication between the immune system and the brain after sepsis as neuroinflammation, oxidative stress, and mitochondrial dysfunction. Stanniocalcin-1 (STC-1), an endogen neuroprotective protein, acts as an anti-inflammatory and suppresses superoxide generation through induction of uncoupling proteins (UCPs) in the mitochondria. Here, we demonstrated a protective role of STC-1 on inflammatory responses in vitro, in activated microglia stimulated with LPS, and on neuroinflammation, oxidative stress, and mitochondrial function in the hippocampus of rats subjected to an animal model of sepsis by cecal ligation and puncture (CLP), as well the consequences on long-term memory. Recombinant human STC-1 (rhSTC1) suppressed the pro-inflammatory cytokine production in LPS-stimulated microglia without changing the UCP-2 expression. Besides, rhSTC1 injected into the cisterna magna decreased acute hippocampal inflammation and oxidative stress and increased the activity of complex I and II activity of mitochondrial respiratory chain and creatine kinase at 24 h after sepsis. rhSTC1 was effective in preventing long-term cognitive impairment after CLP. In conclusion, rhSTC1 confers significant neuroprotection by inhibiting the inflammatory response in microglia and protecting against sepsis-associated encephalopathy in rats.

Sepsis survivors present acute and long-term cognitive impairment and the pathophysiology of neurological dysfunction in sepsis involves microglial activation. Recently, the involvement of cytosolic receptors capable of forming protein complexes called inflammasomes have been demonstrated to perpetuate neuroinflammation. Thus, we investigated the involvement of the NLRP3 inflammasome activation on early and late brain changes in experimental sepsis. Two-month-old male Wistar rats were submitted to the sepsis model by cecal ligation and perforation (CLP group) or laparotomy only (sham group). Immediately after surgery, the animals received saline or NLRP3 inflammasome formation inhibitor (MCC950, 140 ng/kg) intracerebroventricularly. Prefrontal cortex and hippocampus were isolated for cytokine analysis, microglial and astrocyte activation, oxidative stress measurements, nitric oxide formation, and mitochondrial respiratory chain activity at 24 h after CLP. A subset of animals was followed for 10 days for survival assessment, and then behavioral tests were performed. The administration of MCC950 restored the elevation of IL-1β, TNF-α, IL-6, and IL-10 cytokine levels in the hippocampus. NLRP3 receptor levels increased in the prefrontal cortex and hippocampus at 24 h after sepsis, associated with microglial, but not astrocyte, activation. MCC950 reduced oxidative damage to lipids and proteins as well as preserved the activity of the enzyme SOD in the hippocampus. Mitochondrial respiratory chain activity presented variations in both structures studied. MCC950 reduced microglial activation, decreased acute neurochemical and behavioral alteration, and increased survival after experimental sepsis.

Obesity is characterized by chronic inflammation of low grade. The cholinergic anti-inflammatory pathway favors the reduction of the inflammatory response. In this work the effect of stimulation of the cholinergic anti-inflammatory pathway on SHIRPA behavioral test and mitochondrial respiratory chain activity in obese mice was evaluated. The animals were paired in four groups: saline + control diet; donepezil + control diet; saline + high-fat diet and donepezil + high-fat diet. 5 mg/kg/day orally of donepezil or saline were given 7 days before the beginning of the diet until completing 11 weeks of the experiment. Food intake and body weight were measured. At the end of the experiment the animals were submitted to the SHIRPA behavioral test, soon after they were killed by decapitation, the open abdominal cavity and the mesenteric fat were removed. The hypothalamus, hippocampus, prefrontal cortex, and striatum were removed for evaluation of the mitochondrial respiratory chain. It can be observed that donepezil prevented weight gain and food consumption, as well as a tendency to prevent the accumulation of mesenteric fat in obese animals. There was no behavioral change in obese animals, nor did the influence of donepezil on these parameters. On the other hand, donepezil did not prevent inhibition of complex I activity, prevented the inhibition of complex II, and showed a tendency to prevent IV complex activity inhibited in obesity. With these results it can be concluded that the activation of the cholinergic anti-inflammatory pathway is promising for the alterations found in obesity.

Herein, we report the effect of gold nanoparticles (AuNP) and n-acetylcysteine (NAC) isolated or in association as important anti-inflammatory and antioxidant compounds on brain dysfunction in septic rats. Male Wistar rats after sham operation or caecal ligation and perforation (CLP) were treated with subcutaneously injection of AuNP (50 mg/kg) and/or NAC (20 mg/kg) or saline immediately and 12 h after surgery. Twenty-four hours after CLP, hippocampus and prefrontal cortex were obtained and assayed for myeloperoxidase (MPO) activity, cytokines, lipid peroxidation, protein carbonyls formation, mitochondrial respiratory chain, and CK activity. AuNP + NAC association decreased MPO activity and pro-inflammatory cytokines production, being more effective than NAC or AuNP isolated treatment. AuNP + NAC association and NAC isolated treatment decreased oxidative stress to lipids in both brain structures, while protein oxidation decreased only in the hippocampus of AuNP + NAC association-treated animals. Complex I activity was increased with AuNP + NAC association and NAC isolated in the hippocampus. Regarding CK activity, AuNP and AuNP + NAC association increased this marker in both brain structures after CLP. Our data provide the first experimental demonstration that AuNP and NAC association was able to reduce sepsis-induced brain dysfunction in rats by decreasing neuroinflammation, oxidative stress parameters, mitochondrial dysfunction and CK activity.

This study evaluated the effects of omega-3 on inflammation, oxidative stress, and energy metabolism parameters in the brain of mice subjected to high-fat diet-induced obesity model. Body weight and visceral fat weight were evaluated as well. Male Swiss mice were divided into control (purified low-fat diet) and obese (purified high-fat diet). After 6 weeks, the groups were divided into control + saline, control + omega-3, obese + saline, and obese + OMEGA-3. Fish oil (400 mg/kg/day) or saline solution was administrated orally, during 4 weeks. When the experiment completed 10 weeks, the animals were euthanized and the brain and visceral fat were removed. The brain structures (hypothalamus, hippocampus, prefrontal cortex, and striatum) were isolated. Treatment with omega-3 had no effect on body weight, but reduced the visceral fat. Obese animals showed increased inflammation, increased oxidative damage, decreased antioxidant enzymes activity and levels, changes in the Krebs cycle enzyme activities, and inhibition of mitochondrial respiratory chain complexes in the brain structures. Omega-3 treatment partially reversed the changes in the inflammatory and in the oxidative damage parameters and attenuated the alterations in the antioxidant defense and in the energy metabolism (Krebs cycle and mitochondrial respiratory chain). Omega-3 had a beneficial effect on the brain of obese animals, as it partially reversed the changes caused by the consumption of a high-fat diet and consequent obesity. Our results support studies that indicate omega-3 may contribute to obesity treatment.

The current paradigms of prevention and treatment are unable to curb obesity rates, which indicates the need to explore alternative therapeutic approaches. Obesity leads to several damages to the body and is an important risk factor for a number of other chronic diseases. Furthermore, despite the first alterations in obesity being observed and reported in peripheral tissues, studies indicate that obesity can also cause brain damage. Obesity leads to a chronic low-grade inflammatory state, and the therapeutic manipulation of inflammation can be explored. In this context, the use of n-3 PUFA (especially in the form of fish oil, rich in EPA and DHA) may be an interesting strategy, as this substance is known by its anti-inflammatory effect and numerous benefits to the body, such as reduction of TAG, cardiac arrhythmias, blood pressure and platelet aggregation, and has shown potential to help treat obesity. Thereby, the aim of this narrative review was to summarise the literature related to n-3 PUFA use in obesity treatment. First, the review provides a brief description of the obesity pathophysiology, including alterations that occur in peripheral tissues and at the central nervous system. In the sequence, we describe what are n-3 PUFA, their sources and their general effects. Finally, we explore the main topic linking obesity and n-3 PUFA. Animal and human studies were included and alterations on the whole organism were described (peripheral tissues and brain).

Obesity leads to various changes in the body. Among them, the existing inflammatory process may lead to an increase in the production of reactive oxygen species (ROS) and cause oxidative stress. Oxidative stress, in turn, can trigger mitochondrial changes, which is called mitochondrial dysfunction. Moreover, excess nutrients supply (as it commonly is the case with obesity) can overwhelm the Krebs cycle and the mitochondrial respiratory chain, causing a mitochondrial dysfunction, and lead to a higher ROS formation. This increase in ROS production by the respiratory chain may also cause oxidative stress, which may exacerbate the inflammatory process in obesity. All these intracellular changes can lead to cellular apoptosis. These processes have been described in obesity as occurring mainly in peripheral tissues. However, some studies have already shown that obesity is also associated with changes in the central nervous system (CNS), with alterations in the blood-brain barrier (BBB) and in cerebral structures such as hypothalamus and hippocampus. In this sense, this review presents a general view about mitochondrial dysfunction in obesity, including related alterations, such as inflammation, oxidative stress, and apoptosis, and focusing on the whole organism, covering alterations in peripheral tissues, BBB, and CNS.

The present study investigated stress oxidative parameters and activities of enzymes of the energy metabolism in various brain structures. Rats were subjected to acute and long-term administration of gold nanoparticles (GNPs) with mean diameters of 10nm and 30nm. Adult (60days old) male Wistar rats received a single intraperitoneal injection (acute administration; 70μg·kg-1) or repeated injections once daily for 28days (long-term administration; 70μg·kg-1) of saline solution or GNPs (10nm or 30nm). Twenty-four hours after administration of the final dose, the animals were killed and the cerebral structures were isolated for enzyme analysis. In this study, we observed that the thiobarbituric acid-reactive species and carbonyl protein levels were decreased after acute administration of GNPs, whereas the superoxide dismutase activity was increased after acute and long-term of GNPs. The catalase activity was affected by the administration of GNPs. Furthermore, we have not found change in the citrate synthase activity. The succinate dehydrogenase, malate dehydrogenase, complexes I, II, II-III and IV, and creatine kinase activities were altered. These results indicate that inhibition energy metabolism can be caused by oxidative stress.

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.

Neurodegenerative diseases are a growing health concern. The increasing incidences of these disorders have a great impact on the patients' quality of life. Although the mechanisms of neurodegenerative diseases are still far from being clarified, several studies look for new discoveries about their pathophysiology and prevention. Furthermore, evidence has shown a strong correlation between obesity and the development of Alzheimer's disease (AD) and Parkinson's disease (PD). Metabolic changes caused by overweight are related to damage to the central nervous system (CNS), which can lead to neural death, either by apoptosis or cell necrosis, as well as alter the synaptic plasticity of the neuron. This review aims to show the association between neurodegenerative diseases, focusing on AD and PD, and metabolic alterations.

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.

Liraglutide is a human glucagon-like peptide-1 (GLP-1) analogue that was recently approved to treat obesity in some countries. Considering that liraglutide effects on brain energy metabolism are little known, we evaluated the effects of liraglutide on the energy metabolism. Animals received a single or daily injection of saline or liraglutide during 7 days (25, 50, 100, or 300 μg/kg i.p.). Twenty-four hours after the single or last injection, the rats were euthanized and the hypothalamus, prefrontal cortex, cerebellum, hippocampus, striatum, and posterior cortex were isolated. Our results demonstrated that a single dose of liraglutide in young rats increased the activity of complexes and inhibited creatine kinase activity. Repeated administrations of liraglutide in young rats reduced the activity of complexes and activated creatine kinase activity. In adult rats, a single dose of liraglutide reduced the activity of complex I and creatine kinase and increased the activity of complexes II and IV. Repeated administrations of liraglutide in adult rats increased the activity of complexes I and IV and reduced the activity of complex II and creatine kinase. We concluded that liraglutide may interfere in energy metabolism, because analysis of different times of administrations, concentrations, and level of brain development leads to divergent results.

Epidemiological data from the last decades point to an exponential growth in the number of obese people. Different behavioral factors, mainly associated with food consumption, appear to contribute significantly to its development. Concomitant with increased obesity rates, an increase in the consumption of fructose has been observed; therefore, fructose consumption has been implicated as an important obesogenic factor. However, changes in brain activity due to fructose consumption are possible, especially in relation to hypothalamic satiety mechanisms. In addition, the obese state may provide an environment of chronic inflammation and further contribute to the discontinuation of satiety mechanisms in the hypothalamus. We briefly review the intrinsic alterations to the increased adipose tissue, its connections with the hypothalamus in the control of energy signaling mechanisms and, consequently, the participation of fructose as a co-adjuvant or trigger. Presenting the current context with clinical trials involving human and animal studies, we seek to contribute to a better understanding of the role of fructose in the progression of obesity.

In this study, we performed two experiments. In the first experiment, the objective was to link gold nanoparticles (GNPs) with sodium diclofenac and/or soy lecithin and to determine their concentration in tissues and their toxicity using hepatic and renal analyzes in mice to evaluate their safety as therapeutic agents in the subsequent treatment of obesity. In the second experiment, we evaluated the effect of GNPs on inflammatory and biochemical parameters in obese mice. In the first experiment, we synthesized and characterized 18 nm GNPs that were administered intraperitoneally in isolation or in association with sodium diclofenac and/or soy lecithin in mice once daily for 1 or 14 days. Twenty-four hours after the single or final administration, the animals were euthanized, following which the tissues were removed for evaluating the concentration of GNPs, and serum samples were collected for hepatic and renal analysis. Hepatic damage was evaluated based on the levels of alanine aminotransferase (ALT), whereas renal damage was evaluated based on creatinine levels. A higher concentration of GNPs was detected in the tissues upon administration for 14 days, and there were no signs of hepatic or renal damage. In the second experiment, the mice were used as animal models of obesity and were fed a high-fat diet (obese group) and control diet (control group). After eight weeks of high-fat diet administration, the mice were treated with saline or with GNPs (average size of 18 nm) at a concentration of 70 mg/L (70 mg/kg) once a day, for 14 days, for 10 weeks. Body weight and food intake were measured frequently. After the experiment ended, the animals were euthanized, serum samples were collected for glucose and lipid profile analysis, the mesenteric fat content was weighed, and the brains were removed for inflammatory and biochemical analysis. In obese mice, although GNP administration did not reduce body and mesenteric fat weight, it reduced food intake. The glucose levels were reversed upon administration of GNPs, whereas the lipid profile was not altered in any of the groups. GNPs exerted a beneficial effect on inflammation and oxidative stress parameters, without reverting mitochondrial dysfunction. Our results indicate that the intraperitoneal administration of GNPs for 14 days results in a significant GNP concentration in adipose tissues, which could be an interesting finding for the treatment of inflammation associated with obesity. Based on the efficacy of GNPs in reducing dietary intake, inflammation, and oxidative stress, they can be considered potential alternative agents for the treatment of obesity.

Bipolar disorder (BD) is a chronic psychiatric illness characterized by severe and biphasic changes in mood. Several pathophysiological mechanisms have been hypothesized to underpin the neurobiology of BD, including the presence of mitochondrial dysfunction. A confluence of evidence points to an underlying dysfunction of mitochondria, including decreases in mitochondrial respiration, high-energy phosphates and pH; changes in mitochondrial morphology; increases in mitochondrial DNA polymorphisms; and downregulation of nuclear mRNA molecules and proteins involved in mitochondrial respiration. Mitochondria play a pivotal role in neuronal cell survival or death as regulators of both energy metabolism and cell survival and death pathways. Thus, in this review, we discuss the genetic and physiological components of mitochondria and the evidence for mitochondrial abnormalities in BD. The final part of this review discusses mitochondria as a potential target of therapeutic interventions in BD.

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.

This study evaluated the parameters of oxidative stress and energy metabolism after the acute and long-term administration of gold nanoparticles (GNPs, 10 and 30 nm in diameter) in different organs of rats. Adult male Wistar rats received a single intraperitoneal injection or repeated injections (once daily for 28 days) of saline solution, GNPs-10 or GNPs-30. Twenty-four hours after the last administration, the animals were killed, and the liver, kidney, and heart were isolated for biochemical analysis. We demonstrated that acute administration of GNPs-30 increased the TBARS levels, and that GNPs-10 increased the carbonyl protein levels. The long-term administration of GNPs-10 increased the TBARS levels, and the carbonyl protein levels were increased by GNPs-30. Acute administration of GNPs-10 and GNPs-30 increased SOD activity. Long-term administration of GNPs-30 increased SOD activity. Acute administration of GNPs-10 decreased the activity of CAT, whereas long-term administration of GNP-10 and GNP-30 altered CAT activity randomly. Our results also demonstrated that acute GNPs-30 administration decreased energy metabolism, especially in the liver and heart. Long-term GNPs-10 administration increased energy metabolism in the liver and decreased energy metabolism in the kidney and heart, whereas long-term GNPs-30 administration increased energy metabolism in the heart. The results of our study are consistent with other studies conducted in our research group and reinforce the fact that GNPs can lead to oxidative damage, which is responsible for DNA damage and alterations in energy metabolism.

Currently, obesity and its associated complications are considered major public health problems worldwide. Because the causes are multifactorial and complex, different treatment methods are used, which include diet and exercise, as well as the use of drugs, although they can have adverse side effects. A new target for the treatment of obesity may be the incretin system, which consists of hormones that seem to contribute to weight loss. In this sense, some studies have shown a relationship between weight loss and drugs related to incretin system, including glucagon-like peptide-1 (GLP-1) agonists and dipeptidyl peptidase-4 (DPP-4) inhibitors. The objective of this review is to summarize the association between the incretin system and obesity treatment.

The aim of this study was to assess inflammatory parameters, oxidative stress and energy metabolism in the hypothalamus of diet-induced obese mice. Male Swiss mice were divided into two study groups: control group and obese group. The animals in the control group were fed a diet with adequate amounts of macronutrients (normal-lipid diet), whereas the animals in the obese group were fed a high-fat diet to induce obesity. Obesity induction lasted 10 weeks, at the end of this period the disease model was validated in animals. The animals in the obese group had higher calorie consumption, higher body weight and higher weight of mesenteric fat compared to control group. Obesity showed an increase in levels of interleukin 1β and decreased levels of interleukin 10 in the hypothalamus. Furthermore, increased lipid peroxidation and protein carbonylation, and decreased level of glutathione in the hypothalamus of obese animals. However, there was no statistically significant difference in the activity of antioxidant enzymes, superoxide dismutase and catalase. The obese group had lower activity of complex I, II and IV of the mitochondrial respiratory chain, as well as lower activity of creatine kinase in the hypothalamus as compared to the control group. Thus, the results from this study showed changes in inflammatory markers, and dysregulation of metabolic enzymes in the pathophysiology of obesity.

Objective: Several studies support the hypothesis that metabolism impairment is involved in the pathophysiology of depression and that some antidepressants act by modulating brain energy metabolism. Thus, we evaluated the activity of Krebs cycle enzymes, the mitochondrial respiratory chain, and creatine kinase in the brain of rats subjected to prolonged administration of fluvoxamine. Methods: Wistar rats received daily administration of fluvoxamine in saline (10, 30, and 60 mg/kg) for 14 days. Twelve hours after the last administration, rats were killed by decapitation and the prefrontal cortex, cerebral cortex, hippocampus, striatum, and cerebellum were rapidly isolated. Results: The activities of citrate synthase, malate dehydrogenase, and complexes I, II-III, and IV were decreased after prolonged administration of fluvoxamine in rats. However, the activities of complex II, succinate dehydrogenase, and creatine kinase were increased. Conclusions: Alterations in activity of energy metabolism enzymes were observed in most brain areas analyzed. Thus, we suggest that the decrease in citrate synthase, malate dehydrogenase, and complexes I, II-III, and IV can be related to adverse effects of pharmacotherapy, but long-term molecular adaptations cannot be ruled out. In addition, we demonstrated that these changes varied according to brain structure or biochemical analysis and were not dose-dependent.

Studies have consistently reported the participation of oxidative stress, energetic metabolism impairment, and creatine kinase (CK) activity alterations in rat brain in early times in an animal model of sepsis and persist for up to 10 days. We have assessed the antioxidant effects of administration of Ebselen (Eb) e diphenyl diselenide (PhSe)2 two organoselenium compounds on brain oxidative stress, energetic metabolism, and CK activity 12, 24 h, and 10 days after sepsis by cecal ligation and perforation (CLP) in rats. Male Wistar rats underwent either sham operation or CLP and were treated with oral injection of Eb (50 mg/kg) or (PhSe)2 (50 mg/kg) or vehicle. 12, 24 h, and 10 days after CLP, the rats were sacrificed, and samples from brain (hippocampus, striatum, cerebellum, prefrontal cortex, and cortex) were obtained and assayed for thiobarbituric acid reactive species and protein carbonyls formation, mitochondrial respiratory chain, and CK activity. We observed in the results a reduction of oxidative damage to lipids and proteins in the different cerebral structures studied and times with the administration of (PhSe)2; however, Eb seems to exert the same effect. Such changes are reflected in the assessment of mitochondrial respiratory chain complexes by reversing the decreased activity of the complex caused by the model of CLP and CK activity. Our data provide the first experimental demonstration that (PhSe)2 was able to reduce the brain dysfunction associated with CLP-induced sepsis in rats, by decreasing oxidative stress parameters mitochondrial dysfunction and CK activity in early times and in late time.

We evaluated the effects green and mate teas on oxidative and DNA damages in rats exposed to ultraviolet radiation. Were utilized 70 adult male Wistar rats that received daily oral or topic green or mate tea treatment during exposed to radiation by seven days. After, animals were killed by decapitation. Thiobarbituric acid-reactive species levels, protein oxidative damage were evaluated in skin and DNA damage in blood. Our results show that the rats exposed to ultraviolet radiation presented DNA damage in blood and increased protein carbonylation and lipid peroxidation in skin. Oral and topic treatment with green tea and mate tea prevented lipid peroxidation, both treatments with mate tea also prevented DNA damage. However, only topic treatment with green tea and mate tea prevented increases in protein carbonylation. Our findings contribute to elucidate the beneficial effects of green tea and mate tea, here in demonstrated by the antioxidant and antigenotoxic properties presented by these teas.

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.

Objectives: Fenproporex is an amphetamine-based anorectic which is rapidly converted into amphetamine in vivo. Na+, K+-ATPase is a membrane-bound enzyme necessary to maintain neuronal excitability. Considering that the effects of fenproporex on brain metabolism are poorly known and that Na+, K+-ATPase is essential for normal brain function, this study sought to evaluate the effect of this drug on Na+, K+-ATPase activity in the hippocampus, hypothalamus, prefrontal cortex, and striatum of young rats. Methods: Young male Wistar rats received a single injection of fenproporex (6.25, 12.5, or 25 mg/kg intraperitoneally) or polysorbate 80 (control group). Two hours after the last injection, the rats were killed by decapitation and the brain was removed for evaluation of Na+, K+-ATPase activity. Results: Fenproporex decreased Na+, K+-ATPase activity in the striatum of young rats at doses of 6.25, 12.5, and 25 mg/kg and increased enzyme activity in the hypothalamus at the same doses. Na+, K+-ATPase activity was not affected in the hippocampus or prefrontal cortex. Conclusion: Fenproporex administration decreased Na+, K+-ATPase activity in the striatum even in low doses. However, in the hypothalamus, Na+, K+-ATPase activity was increased. Changes in this enzyme might be the result of the effects of fenproporex on neuronal excitability.

BackgroundThe World Health Organization estimates that major depression affects about 350 million people all over the world and reports this disorder as the major contributor to the global burden of diseases. Despite the well-defined symptomatology, major depression is a heterogeneous psychiatric disorder whose pathophysiology is not clearly established. Although several treatments are available, most depressed patients do not achieve the complete remission of symptoms. Factors linked to the persistence of the disorder have been investigated, particularly those related to the way of life. Moreover, it has been suggested that nutritional aspects may influence its development. Among them, a diet rich in ω-3 has been associated with a reduced risk of major depression, although its deficiency is associated with depressive disorders.MethodsThis review provides a general view about evidences of the use of ω-3 in major depression cases.ResultsSeveral studies have demonstrated beneficial effects of ω-3 in the prevention and treatment of major depression. However, not all the results have shown significant statistical benefits.ConclusionsMore studies are necessary to clarify detailed mechanisms of the antidepressant effects of ω-3 and may explain the source of contradictions in results published until the moment.

Evidence suggests that mitochondrial dysfunction is involved in the pathophysiology of psychiatric disorders such as schizophrenia (SZ) and bipolar disorder (BD). However, the exact mechanisms underlying this dysfunction are not well understood. Impaired activity of electron transport chain (ETC) complexes has been described in these disorders and may reflect changes in mitochondrial metabolism and oxidative stress markers. The objective of this study was to compare ETC complex activity and protein and lipid oxidation markers in 12 euthymic patients with BD type I, in 18 patients with stable chronic SZ, and in 30 matched healthy volunteers. Activity of complexes I, II, and III was determined by enzyme kinetics of mitochondria isolated from peripheral blood mononuclear cells (PBMCs). Protein oxidation was evaluated using the protein carbonyl content (PCC) method, and lipid peroxidation, the thiobarbituric acid reactive substances (TBARS) assay kit. A significant decrease in complex I activity was observed (p = 0.02), as well as an increase in plasma levels of TBARS (p = 0.00617) in patients with SZ when compared to matched controls. Conversely, no significant differences were found in complex I activity (p = 0.17) or in plasma TBARS levels (p = 0.26) in patients with BD vs. matched controls. Our results suggest that mitochondrial complex I dysfunction and oxidative stress play important roles in the pathophysiology of SZ and may be used in potential novel adjunctive therapy for SZ, focusing primarily on cognitive impairment and disorder progression.

Traumatic brain injury (TBI) induces glutamatergic excitotoxicity through N-methyl-D-aspartate (NMDA) receptors, affecting the integrity of the mitochondrial membrane. Studies have pointed to mitochondria as the master organelle in the preconditioning-triggered endogenous neuroprotective response. The present study is aimed at understanding energy metabolism in the brains of mice after preconditioning with NMDA and TBI. For this purpose, male albino CF-1 mice were pre-treated with NMDA (75 mg/kg) and subjected to brain trauma. Mitochondrial respiratory chain and creatine kinase activities were assessed at 6 or 24 h after trauma. The mice preconditioned and subjected to TBI exhibited augmented activities of complexes II and IV in the cerebral cortex and/or cerebellum. Creatine kinase activity was also augmented in the cerebral cortex after 24 h. We suggest that even though NMDA preconditioning and TBI have similar effects on enzyme activities, each manage their response via opposite mechanisms because the protective effects of preconditioning are unambiguous. In conclusion, NMDA preconditioning induces protection via an increase of enzymes in the mitochondria.

Obesity is a chronic and multifactorial disease, whose prevalence is increasing in many countries. Pharmaceutical strategies for the treatment of obesity include drugs that regulate food intake, thermogenesis, 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, which is associated with neurotoxicity. In this context, the present study evaluated DNA damage parameters in the peripheral blood of young and adult rats submitted to an acute administration and chronic administration of fenproporex. In the acute administration, both young and adult rats received a single injection of fenproporex (6.25, 12.5 or 25 mg/kg i.p.) or vehicle. In the chronic administration, both young and adult rats received one daily injection of fenproporex (6.25, 12.5, or 25 mg/kg i.p.) or Tween for 14 days. 2 h after the last injection, the rats were killed by decapitation and their peripheral blood removed for evaluation of DNA damage parameters by alkaline comet assay. Our study showed that acute administration of fenproporex in young and adult rats presented higher levels of damage index and frequency in the DNA. However, chronic administration of fenproporex in young and adult rats did not alter the levels of DNA damage in both parameters of comet assay. The present findings showed that acute administration of fenproporex promoted damage in DNA, in both young and adult rats. Our results are consistent with other reports which showed that other amphetamine-derived drugs also caused DNA damage. We suggest that the activation of an efficient DNA repair mechanism may occur after chronic exposition to fenproporex. Our results are consistent with other reports that showed some amphetamine-derived drugs also caused DNA damage.

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.

Objectives: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.Methods:Adult male Wistar rats received a single intracerebroventricular administration of ouabain (10−3and 10−2M) 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.Results: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 10−3and 10−2M. Moreover, complex II activity was increased only in the prefrontal cortex at the concentration of 10−2M. 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 10−2M.Conclusion: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.

Objectives:Based on the hypothesis that energy impairment may be involved in the pathophysiology of depression, we evaluated the activities of citrate synthase, malate dehydrogenase, succinate dehydrogenase (SDH), mitochondrial respiratory chain complexes I, II, II-III, IV and creatine kinase (CK) in the brain of rats submitted to chronic administration of bupropion.Methods:Animals received daily administration of bupropion dissolved in saline (10 mg/kg, intraperitoneal) at 1.0 ml/kg body weight. The rats received injections once a day for 14 days; control rats received an equivalent volume of saline. Twelve hours after the last administration, the rats were killed by decapitation and brain was rapidly removed and kept on an ice plate. The activities of the enzymes were measured in different brain areas.Results:We observed that the activities of citrate synthase and malate dehydrogenase, mithocondrial respiratory chain complexes I, II-III and IV and CK were not altered after chronic administration of bupropion. However, SDH activity was increased in the prefrontal cortex and cerebellum. In the hippocampus, cerebellum and striatum the activity of complex II was increased after chronic administration of bupropion.Conclusions:Our results demonstrated that bupropion increased some enzymes of brain energy metabolism. These findings are in accordance with other studies which showed that some antidepressants may improve energy metabolism. The present results reinforce the hypothesis that antidepressants modulate brain energy metabolism.

Objective:Considering that mitochondria may be drug targets and some characteristics of drug–mitochondria interactions may still be misjudged because of the difficulty in foreseeing and understanding all possible implications of the complex pathophysiology of mitochondria, our study aimed to investigate the effect of escitalopram on the activity of enzymes of mitochondrial energy metabolism.Methods:Animals received daily administration of escitalopram dissolved in saline [10 mg/kg, intraperitoneal (IP)] at 1.0 ml/kg volume for 14 days. Control rats received an equivalent volume of saline, 1.0 ml/kg (IP), for the same treatment period. Twelve hours after last injection, rats were killed by decapitation and brain areas were rapidly isolated. The samples were homogenised and the activities of mitochondrial respiratory chain complexes, some enzymes of Krebs cycle (citrate synthase, malate dehydrogenase and succinate dehydrogenase) and creatine kinase were measured.Results:We verified that chronic administration of escitalopram decreased the activities of complexes I and II–III in cerebellum, hippocampus, striatum and posterior cortex whereas prefrontal cortex was not affected. Complex II activity was decreased only in striatum without affecting prefrontal cortex, hippocampus, cerebellum and posterior cortex. However, chronic administration of escitalopram did not affect complex IV and enzymes of Krebs cycle activities as well as creatine kinase.Conclusion:In this study we showed a decrease in the activities of complexes I and II–III in most of the brain structures analysed and complex II activity was decreased only in striatum. However, it remains to be determined if mitochondrial dysfunction is rather a causal or a consequential event of abnormal signalling.

Problem statement: In bacterial meningitis, the Streptococcus pneumoniae can modify the cerebro-spinal fluid (CSF) homeostasis and initiation of the host inflammatory response with presence cytokine and leukocyte migration into the subarachnoidal space. Despite the availability of highly effective antibiotics, the disease is often fatal or causes long-term neurological problems in affected patients. Approach: The aim of this study was to evaluate the effect of this new compound P0801 in the oxidative stress, mitochondrial respiratory chain and brain Creatine Kinase activity (CK) in adult rats after meningitis by S.pneumoniae. Results: In our study, the group of animals with pneumococcal meningitis that received P0801, with or without antibiotic therapy at 24 h after induction decreased protein carbonyls in cerebral cortex and in the hippocampus at 48 h after induction, being that the same time decreased lipid peroxidation. In the animals that received antibiotic therapy and or treatment with P0801 at 24 h after induction of meningitis, there were increased by the activity of complex I, II, IV and enzyme succinate dehydrogenase in cerebral cortex, being that at 48 h in the group that received antibiotic therapy and or P0801, there were increased by the activity of complex I, II and succinate dehydrogenase in the cerebral cortex and or hippocampus. In our study, the CK activity was increased in hippocampus and cerebral cortex at 24 h after induction meningitis in the group that received antioxidant treatment and only in cerebral cortex in the group that received antibiotic therapy with antioxidant treatment. Conclusion/Recommendations: The study with new compound is an attempt to coadjuvant treatment with the antibiotic to minimize the oxidative damage and energy metabolism during illness. New studies are needed to clarify the action of this new compound as coadjuvant, evaluating side effects and their formulation, since it might look promising in the development of novel therapeutic agents in further studies.

Obesity is a multifactorial disease that comes from an imbalance between food intake and energy expenditure. Moreover, studies have shown a relationship between mitochondrial dysfunction and obesity. In the present study, we investigated the effect of acerola juices (unripe, ripe, and industrial) and its main pharmacologically active components (vitamin C and rutin) on the activity of enzymes of energy metabolism in the brain of mice fed a palatable cafeteria diet. Two groups of male Swiss mice were fed on a standard diet (STA) or a cafeteria diet (CAF) for 13 weeks. Afterwards, the CAF-fed animals were divided into six subgroups, each of which received a different supplement for one further month (water, unripe, ripe or industrial acerola juices, vitamin C, or rutin) by gavage. Our results demonstrated that CAF diet inhibited the activity of citrate synthase in the prefrontal cortex, hippocampus, and hypothalamus. Moreover, CAF diet decreased the complex I activity in the hypothalamus, complex II in the prefrontal cortex, complex II-III in the hypothalamus, and complex IV in the posterior cortex and striatum. The activity of succinate dehydrogenase and creatine kinase was not altered by the CAF diet. However, unripe acerola juice reversed the inhibition of the citrate synthase activity in the prefrontal cortex and hypothalamus. Ripe acerola juice reversed the inhibition of citrate synthase in the hypothalamus. The industrial acerola juice reversed the inhibition of complex I activity in the hypothalamus. The other changes were not reversed by any of the tested substances. In conclusion, we suggest that alterations in energy metabolism caused by obesity can be partially reversed by ripe, unripe, and industrial acerola juice.

Several studies have appointed for a role of glutamatergic system and/or mitochondrial function in major depression. In the present study, we evaluated the creatine kinase and mitochondrial respiratory chain activities after acute and chronic treatments with memantine (N-methyl-D: -aspartate receptor antagonist) and imipramine (tricyclic antidepressant) in rats. To this aim, rats were acutely or chronically treated for 14 days once a day with saline, memantine (5, 10 and 20 mg/kg) and imipramine (10, 20 and 30 mg/kg). After acute or chronic treatments, we evaluated mitochondrial respiratory chain complexes (I, II, II-III and IV) and creatine kinase activities in prefrontal cortex, hippocampus and striatum. Our results showed that both acute and chronic treatments with memantine or imipramine altered respiratory chain complexes and creatine kinase activities in rat brain; however, these alterations were different with relation to protocols (acute or chronic), complex, dose and brain area. Finally, these findings further support the hypothesis that the effects of imipramine and memantine could be involve mitochondrial function modulation.

The pathophysiology of gastritis involves an imbalance between gastric acid attack and mucosal defence. In addition, the gastric mucosal injury results in adenosine triphosphate (ATP) depletion leading to mitochondrial dysfunction. Several studies have shown the association of mitochondrial disorders with gastrointestinal dysfunction. In the present study, we investigated the activity of mitochondrial respiratory chain complexes activity in the stomach of rats with gastritis induced by indomethacin (IDM) and treated with omeprazole (OM), N-acetylcysteine (NAC) and the gastrin-releasing peptide receptor (GRPR) antagonist RC-3095. Adult male Wistar rats were pre-treated for 7 days with OM, NAC, RC-3095, combination of OM plus RC-3095, OM plus NAC and water (control). The animals were then submitted to fasting for 24 hr; IDM was administered. The rats were killed 6 hr later, and the stomachs were used for evaluation of macroscopic damage and respiratory chain activity. Our results showed that complex I and IV activities were not affected by administration of IDM. On the other hand, complex II and III activities were inhibited. In addition, OM plus RC-3095 and OM plus NAC did not reverse complex II activity inhibition. However, the complex III activity inhibition was reversed only with the combined use of OM plus RC-3095 and OM plus NAC. Our results are in agreement with previous studies indicating mitochondrial dysfunction in the pathophysiology of gastrointestinal tract disease and we suggest that GRPR antagonism might be a novel therapeutic strategy in gastritis.

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.

The brain is highly dependent on ATP and most cell energy is obtained through oxidative phosphorylation, a process requiring the action of various respiratory enzyme complexes located in a special structure of the inner mitochondrial membrane. Bacterial meningitis due to Streptococcus pneumoniae is associated with a significant mortality rate and persisting neurologic sequelae including sensory-motor deficits, seizures, and impairments of learning and memory. In this context, we evaluated the activities of mitochondrial respiratory chain complexes in the brain of rats submitted to meningitis by S. pneumoniae inoculation into the cisterna magna. Our results demonstrated that complex I activity was not altered in cerebral cortex after meningitis; complexes II, III and IV were increased 24 and 48 h after meningitis. We have also verified that complex I was inhibited in prefrontal cortex 48 h after meningitis; complexes II, III and IV were not altered. Our results also demonstrated that complex I activity was inhibited in striatum, hippocampus and cerebellum 24 h after meningitis. Moreover, complex II activity was increased in hippocampus and striatum 24 and 48 h after meningitis; complexes III and IV activity were increased in striatum, hippocampus and cerebellum 48 h after meningitis. Taking together previous reports and our present findings, we speculate that oxidative stress and metabolism impairment might contribute, at least in part, for the pathogenesis of pneumococcal meningitis.

Evidence from the literature has shown that the wound healing process is enhanced by ultrasound therapy. In the present study, we measured thiobarbituric acid-reactive substances (TBARS; index of lipoperoxidation) and hydroxyproline (index of collagen synthesis) levels in wounds after therapeutic pulsed ultrasound (TPU) treatment. Male Wistar rats were submitted to skin ulceration, and three doses of TPU (0.4, 0.6, and 0.8W/cm(2)) were used. A circular area of skin was removed with a punch biopsy from the medial dorsal region. After TPU for 10 days, TBARS (Draper and Hadley [21]) and hydroxyproline (Woessner [22]) levels were measured in the tissue around the wound. Results showed that TPU improved wound healing, since the wound size was significantly smaller 5 and 10 days after ulceration in groups submitted to this treatment. Moreover, TBARS levels were decreased in the 0.4, 0.6, and 0.8W/cm(2) TPU groups, and hydroxyproline levels were increased in the 0.6 and 0.8W/cm(2) TPU groups. These findings indicate that TPU presents beneficial effects on the wound healing process, probably by speeding up the inflammatory phase and inducing collagen synthesis.

Several works report brain impairment of metabolism as a mechanism underlying depression. Citrate synthase and succinate dehydrogenase are enzymes localized within cells in the mitochondrial matrix and are important steps of Krebs cycle. In addition, citrate synthase has been used as a quantitative enzyme marker for the presence of intact mitochondria. Thus, we investigated citrate synthase and succinate dehydrogenase activities from rat brain after chronic administration of paroxetine, nortriptiline and venlafaxine. Adult male Wistar rats received daily injections of paroxetine (10 mg/kg), nortriptiline (15 mg/kg), venlafaxine (10 mg/kg) or saline in 1.0 mL/kg volume for 15 days. Twelve hours after the last administration, the rats were killed by decapitation, the hippocampus, striatum and prefrontal cortex were immediately removed, and activities of citrate synthase and succinate dehydrogenase were measured. We verified that chronic administration of paroxetine increased citrate synthase activity in the prefrontal cortex, hippocampus, striatum and cerebral cortex of adult rats; cerebellum was not affected. Chronic administration of nortriptiline and venlafaxine did not affect the enzyme activity in these brain areas. Succinate dehydrogenase activity was increased by chronic administration of paroxetine and nortriptiline in the prefrontal cortex, hippocampus, striatum and cerebral cortex of adult rats; cerebellum was not affected either. Chronic administration of venlafaxine increased succinate dehydrogenase activity in prefrontal cortex, but did not affect the enzyme activity in cerebellum, hippocampus, striatum and cerebral cortex. Considering that metabolism impairment is probably involved in the pathophysiology of depressive disorders, an increase in these enzymes by antidepressants may be an important mechanism of action of these drugs.