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

BACKGROUND

Biomedical research has recently incorporated bioceramics applications into new health care approaches.

OBJECTIVE

This study evaluated the effect of far infrared-emitting bioceramics wraps in the treatment of intermittent claudication.

METHODS

This is a randomized double-blind placebo-controlled pilot study. Thirty-five patients met the criteria and were randomized into either control (placebo wraps) or bioceramics group (far infrared emitting-ceramics wraps) and assessed over a 90-day period for the following outcomes: six-minute walk test (6MWT), ankle-brachial index (ABI), Flow-mediated arterial dilation (FMD), quality of life and claudication. Oxidative stress and inflammatory biomarkers were measured in plasma of patients.

RESULTS

Intervention induced a decrease in oxidative stress, with significant lower levels of reactive substances to thiobarbituric acid (TBARS), as well as increase in superoxide dismutase and catalase enzyme activities. There was an increase in the environment subscale of the quality of life questionnaire. No statistically significant differences were found in the inflammatory cytokines, 6MWT, ABI and FMV evaluations.

CONCLUSIONS

In Sum, FIR treatment improved oxidative stress profile and quality-of-life of patients with intermittent claudication. The study was registered into the ensaiosclinicos.gov.br (Registro Brasileiro de Ensaios Clínicos [ReBEC]) (RBR-7nr6sy register number).

Gold nanoparticles potentiates N-acetylcysteine effects on neurochemicals alterations in rats after polymicrobial sepsis

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.

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

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

PET imaging of TSPO in a rat model of sepsis induced by peritoneal polymicrobial infection

Background

Sepsis is a life-threatening acute organ dysfunction secondary to infection that affects more than 30 million people worldwide. In the USA, 1.5 million people develop sepsis, and at least 250,000 Americans die from sepsis each year. After hospitalization, patients suffer from long-term impairments in memory, attention, verbal fluency, and executive functioning. The translocator protein (TSPO), marker of activated microglia astrocytes cells, can be measured in vivo using positron emission tomography (PET). Our working hypothesis is that systemic inflammation associated with sepsis activate microglia cells, which will later lead to further long-term cognitive impairment in sepsis survivors.

Methods

To test this hypothesis, adult male Wistar rats were subjected to a gold standard sepsis model induced by cecal ligation and perforation (CLP) surgery to induce peritoneal poly microbial sepsis or sham surgery as a control group. At 24 hour after the surgery the animals were subjected to translocator protein (TSPO) microPET imaging with [11C]PBR28. Following the imaging, TSPO, cytochrome C, cytokines/chemokines, microglia (Iba-1) and astrocyte marker (GFAP) were measured in the prefrontal cortex and hippocampus of the septic animals.

Results

septic animals presented and increased uptake of [11C]PBR28-microglia activation in the whole brain compared to control at 24 after the CLP surgery. The expression of IL-1α, IL-1β, IL-6, IL-18, TNF-α, IFN-γ and Iba-1 increased in the hippocampus of septic rat.

Conclusion

The upregulation of TSPO expression in the hippocampus of septic rat brain is a possible mechanism associated with long-term cognitive impairment in sepsis survivors.

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

OBJECTIVES

Sepsis is a severe organic dysfunction caused by an infection that affects the normal regulation of several organ systems, including the central nervous system. Inflammation and oxidative stress play crucial roles in the development of brain dysfunction in sepsis. The aim of this study was to determine the effect of a fish oil (FO)-55-enriched lipid emulsion as an important anti-inflammatory compound on brain dysfunction in septic rats.

METHODS

Wistar rats were subjected to sepsis by cecal ligation and perforation (CLP) or sham (control) and treated orally with FO (600 µL/kg after CLP) or vehicle (saline; sal). Animals were divided into sham+sal, sham+FO, CLP+sal and CLP+FO groups. At 24 h and 10 d after surgery, the hippocampus, prefrontal cortex, and total cortex were obtained and assayed for levels of interleukin (IL)-1β and IL-10, blood-brain barrier permeability, nitrite/nitrate concentration, myeloperoxidase activity, thiobarbituric acid reactive species formation, protein carbonyls, superoxide dismutase and catalase activity, and brain-derived neurotrophic factor levels. Behavioral tasks were performed 10 d after surgery.

RESULTS

FO reduced BBB permeability in the prefrontal cortex and total cortex of septic rats, decreased IL-1β levels and protein carbonylation in all brain structures, and diminished myeloperoxidase activity in the hippocampus and prefrontal cortex. FO enhanced brain-derived neurotrophic factor levels in the hippocampus and prefrontal cortex and prevented cognitive impairment.

CONCLUSIONS

FO diminishes the negative effect of polymicrobial sepsis in the rat brain by reducing inflammatory and oxidative stress markers.

Oxidative stress and mitochondrial dysfunction contributes to postoperative cognitive dysfunction in elderly rats

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.

Maternal immune activation induced by lipopolysaccharide triggers response inflammatory, oxidative damage and damage to blood brain barrier integrity and placental barrier in Wistar rats pregnant and fetus

Evidence suggest that prenatal immune system disturbance contributes largely to the pathophysiology of neuropsychiatric disorders. A bacterial infection animal model widely accepted is administration of lipopolysaccharide (LPS). We investigated if maternal immune activation (MIA) could induce inflammatory alterations, oxidative damage and damage to blood brain barrier integrity (BBB) and placental barrier (PB) in fetal brain and pregnant Wistar rats. On gestational day 15, Wistar pregnant rats received LPS (0.25 mg/kg) to induce MIA. After 6, 12 and 24 h, fetus brain, placenta, and amniotic fluid were collected to evaluate early effects of LPS. Other group of rats from postnatal day (PND) 54 received injection of ketamine at the doses of 5, 15, and 25 mg/kg. On PND 60 rats were subjected to the spontaneous locomotor activity and pre-pulse inhibition test (PPI). MIA increased oxidative stress in the amniotic fluid and fetal brain. The BBB integrity in the hippocampus and cerebral cortex as well integrity of PB in the placenta and fetus brain were dysregulated after LPS induction. We also found elevated levels of cytokines such as interleukin (IL)-1β, IL-2, IL-4, IL-5, interferon (IFN)-γ, macrophage colony stimulating factor (M-CSF), IL-6, IL-10, IL-18, macrophage inflammatory protein (MIP)-3a, tumor necrosis factor (TNF)-α-, IL-7, MIP-1a and erythropoietin. Rats that receive MIA plus ketamine had locomotor activity impairment and a deficit in the PPI. In the present study, it was concluded that MIA increased the permeability of BBB and PB, the circulation of inflammatory mediators in fetal brains. This immune response in the prenatal period may be responsible for the behavioral changes in the adult life of offspring induced by MIA.

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

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

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

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

Long-Term Cognitive Outcomes After Sepsis: a Translational Systematic Review

Sepsis is systemic inflammatory response syndrome with a life-threatening organ dysfunction that is caused by an unbalanced host immune response in an attempt to eliminate invasive microorganisms. We posed questions, "Does sepsis survivor patients have increased risk of neuropsychiatric manifestations?" and "What is the mechanism by which sepsis induces long-term neurological sequelae, particularly substantial cognitive function decline in survivor patients and in pre-clinical sepsis models?" The studies were identified by searching PubMed/MEDLINE (National Library of Medicine), PsycINFO, EMBASE (Ovid), LILACS (Latin American and Caribbean Health Sciences Literature), IBECS (Bibliographical Index in Spanish in Health Sciences), and Web of Science databases for peer-reviewed journals that were published until January 2018. A total of 3555 papers were included in the primary screening. After that, 130 articles were selected for the study. A number of pre-clinical studies have shown an auto amplification of pro-inflammatory cytokines such as tumor necrosis factor alpha (TNF-α), interleukin (IL)-1β, and IL-6 in the first few hours after sepsis induction, also increased blood-brain barrier permeability, elevated levels of matrix metalloproteinases, increased levels of damage-associated molecular patterns were demonstrated. In addition, the rodents presented long-term cognitive impairment in different behavioral tasks that were prevented by blocking the mechanism of action of these inflammatory mediators. Clinical studies have showed that sepsis survivors presented increased bodily symptoms such as fatigue, pain, visual disturbances, gastrointestinal problems, and neuropsychiatric problems compared to before sepsis. Sepsis leaves the survivors with an aftermath of physiological, neuropsychiatric, and functional impairment. Systematic review registration: CRD42017071755.

The inhibition of the kynurenine pathway prevents behavioral disturbances and oxidative stress in the brain of adult rats subjected to an animal model of schizophrenia

Evidence has shown that the kynurenine pathway (KP) plays a role in the onset of oxidative stress and also in the pathophysiology of schizophrenia. The aim of this study was to use a pharmacological animal model of schizophrenia induced by ketamine to investigate if KP inhibitors could protect the brains of Wistar rats against oxidative stress and behavioral changes. Ketamine, injected at the dose of 25mg/kg, increased spontaneous locomotor activity. However, the inhibitors of tryptophan 2,3-dioxygenase (TDO), indoleamine 2,3-dioxygenase (IDO) and kynurenine-3-monooxygenase (KMO) were able to reverse these changes. In addition, the IDO inhibitor prevented lipid peroxidation, and decreased the levels of protein carbonyl in the prefrontal cortex (PFC), hippocampus and striatum. It also increased the activity of superoxide dismutase (SOD) in the hippocampus, as well as increasing the levels of catalase activity in the PFC and hippocampus. The TDO inhibitor prevented lipid damage in the striatum and reduced the levels of protein carbonyl in the hippocampus and striatum. Also, the TDO inhibitor increased the levels of SOD activity in the striatum and CAT activity in the hippocampus of ketamine-induced pro-oxidant effects. Lipid damage was not reversed by the KMO inhibitor. The KMO inhibitor increased the levels of SOD activity in the hippocampus, and reduced the levels of protein carbonyl while elevating the levels of CAT activity in the striatum of rats that had been injected with ketamine. Our findings revealed that the KP pathway could be a potential mechanism by which a schizophrenia animal model induced by ketamine could cause interference by producing behavioral disturbance and inducing oxidative stress in the brain, suggesting that the inhibition of the KP pathway could be a potential target in treating schizophrenia.

Acute and chronic treatment with quetiapine induces antidepressant-like behavior and exerts antioxidant effects in the rat brain

Many studies note that changes in oxidative balance are involved in the pathogenesis of major depressive disorder (MDD) and in the success of some antidepressants. Quetiapine exerts a therapeutic response and induces changes in physiological mechanisms that appear to underlie MDD. The objective of this study was to evaluate the antidepressant and antioxidant effects of quetiapine (20 mg /kg) in adult animals. Sixty minutes after an acute treatment or the last administration of chronic treatment (14 days) with quetiapine, animals were subjected to the forced swimming test (FST) to evaluate mobility parameters. Then, the hippocampus, prefrontal cortex (CPF), amygdala and nucleus accumbens (NAc) were removed for the assessment of oxidative stress parameters. Both acute and chronic treatments exerted antidepressant-like effects. Myeloperoxidase (MPO) activity was reduced in the amygdala after acute treatment and in the hippocampus, PFC and amygdala after chronic treatment. In addition, after chronic treatment, the levels of thiobarbituric reactive species (TBARS) were reduced in the amygdala and NAc, and the protein carbonyl content was reduced in the CPF. Superoxide dismutase (SOD) activity increased in the NAc after acute and chronic treatments. Catalase (CAT) activity increased in the PFC after acute treatment and in the NAc after acute and chronic treatments. The concentration of nitrite/nitrate was lower in the CPF after chronic treatment. These results corroborate the antidepressant effect of quetiapine and indicate that quetiapine exhibits an antioxidant profile, a physiological mechanism that appears be involved in the therapeutic function of quetiapine in individuals resistant to classical antidepressant treatments.

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

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

Mechanism of synergistic action on behavior, oxidative stress and inflammation following co-treatment with ketamine and different antidepressant classes

BACKGROUND

Major depressive disorder (MDD) affects many people in the world. However, around 40% of patients do not respond to any pharmacological drugs. An alternative is to use a combination of different pharmacological groups or the combination of a classical antidepressant with a substance that can potentiate its effect. Thus, this study aimed to investigate the synergistic interactions between different antidepressants, including fluoxetine, quetiapine and lamotrigine in combination with ketamine, a N-methyl-d-aspartate (NMDA) receptor antagonist.

METHODS

Wistar rats were acutely treated with fluoxetine (1.25mg/kg), quetiapine (5mg/kg), and lamotrigine (5.0mg/kg) alone or in combination with ketamine (5.0mg/kg), and then subjected to behavioral tests. In addition, oxidative damage and antioxidant capacity were assessed in the rat brain, and pro-inflammatory cytokines levels were evaluated in the serum.

RESULTS

It was observed a synergistic effect of ketamine in combination with fluoxetine on the immobility time in the forced swimming test, indicating an antidepressant effect. Other antidepressant did not show effects when administrated alone or joint to ketamine. The combination of ketamine with other antidepressants, particularly quetiapine, in some brain regions induced an increase in damage to lipids and proteins. However, the combination of ketamine with fluoxetine increased the antioxidant activity of superoxide dismutase, and decreased oxidative damage, thus suggesting a neuroprotective effect of the combination of these drugs. The combination of ketamine with fluoxetine or lamotrigine reduced pro-inflammatory cytokines levels.

CONCLUSION

In conclusion, ketamine induced antioxidant or pro-antioxidant effects dependent of antidepressant classes or brain area.

RAGE antagonist decreases β-amyloid, HMGB-1, RAGE expression in the brain, and prevented long-term cognitive impairment in experimental bacterial meningitis

Bacterial meningitis is a serious infection of the central nervous system that causes learning and memory impairment. Our central hypothesis is that during meningitis, the inflammation increases the synthesis of amyloid-beta (Aβ1-42) and up regulates receptor for advanced glycation end products (RAGE). Then the Aβ-RAGE-axis triggers long-term cognitive impairment in meningitis survivors. To test this, we evaluated Aβ1-42 deposition, RAGE, and high mobility group box-1 (HMGB-1) expression in the rat brain. We evaluated the behavioural response by treating the rats with RAGE-antagonist, N-benzyl-4-chloro-N-cyclohexylbenzamide (FPS-ZM1). The animals were separated into four groups: control/saline, control/FPS-ZM1, meningitis/saline, and meningitis/FPS-ZM1 (n=10). Experimental design: male 60-day-old Wistar rats received an intracisternal injection of 10 μL of artificial cerebrospinal fluid as a placebo or an equivalent volume of Streptococcus pneumoniae suspension at concentration of 5×109 CFU/mL. Eighteen hours after meningitis induction, all animals received ceftriaxone. Ten days after inoculation all blood cultures performed were negative showing that the animals were free from infection. At 10 day after meningitis induction the results from western-blot showed increased expression of Aβ, RAGE, and HMGB-1 in the hippocampus and prefrontal cortex of meningitis group. The FPS-ZM1 adjuvant treatment prevented the Aβ1-42, RAGE, and HMGB-1 expression in both brain structures and prevented long-term memory impairment in the meningitis group. The bacterial meningitis may trigger cognitive impairment through up-regulating Aβ-RAGE axis and RAGE-antagonist prevented cognitive impairment.

Evidence of oxidative stress in brain and liver of young rats submitted to experimental galactosemia

Galactosemia is a disorder of galactose metabolism, leading to the accumulation of this carbohydrate. Galactosemic patients present brain and liver damage. For evaluated oxidative stress, 30-day-old males Wistar rats were divided into two groups: galactose group, that received a single injection of this carbohydrate (5 μmol/g), and control group, that received saline 0.9 % in the same conditions. One, twelve or twenty-four hours after the administration, animals were euthanized and cerebral cortex, cerebellum, and liver were isolated. After one hour, it was found a significant increase in TBA-RS levels, nitrate and nitrite and protein carbonyl contents in cerebral cortex, as well as protein carbonyl content in the cerebellum and in hepatic level of TBA-RS, and a significant decrease in nitrate and nitrite contents in cerebellum. TBA-RS levels were also found increased in all studied tissues, as well as nitrate and nitrite contents in cerebral cortex and cerebellum, that also present increased protein carbonyl content and impairments in the activity of antioxidant enzymes of rats euthanized at twelve hours. Finally, animals euthanized after twenty-four hours present an increase of TBA-RS levels in studied tissues, as well as the protein carbonyl content in cerebellum and liver. These animals also present an increased nitrate and nitrite content and impairment of antioxidant enzymes activities. Taken together, our data suggest that acute galactose administration impairs redox homeostasis in brain and liver of rats.

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

ETHNOPHARMACOLOGICAL RELEVANCE

Cecropia glaziovii Sneth leaves extract is widely used as a traditional folk medicine in Brazil, especially for the treatment of diabetes, and as an antihypertensive and antiinflammatory agent.

AIM OF THE STUDY

To investigate the anti-inflammatory and antioxidant properties of crude aqueous extract (CAE) of C. glaziovii leaves.

MATERIALS AND METHODS

The in vivo anti-inflammatory and antioxidant effect of the CAE (10-300mg/kg, intragastrically) was investigated in the animal model of pleurisy. The cell migration, proinflammatory cytokines (TNF-α, IL-1β and IL-6), nitrite/nitrate concentration, myeloperoxidase (MPO) activity, oxidative damage in lipids and proteins, lactate dehydrogenase (LDH) activity and total protein content were also analyzed. Furthermore, the in vitro antioxidant activity of CAE was evaluated by the inhibition of formation of thiobarbituric acid reactive substances (TBARS), induced by free radical generators (H2O2, FeSO4 and AAPH) on a lipid-rich substrate. Hence, the chemical characterizarion of CAE by HPLC was therefore performed. The results showed that the inflammatory process caused by the administration of carragenin (Cg) into the pleural cavity resulted in a substantial increase in inflammatory parameters and oxidative damage. These levels seems to be reversed after CAE treatment in animals with similar results to Dexamethasone (Dex) treatment. Further, the CAE was effective in reducing proinflammatory cytokines, cell infiltrate, MPO activity, nitrite/nitrate concentration, LDH activity, and total protein levels with concomitant attenuation of all parameters associated with oxidative damage induced by Cg. Finally, the CAE presented in vitro antioxidant activity induced by free radical generators at all the concentrations investigated. HPLC analysis confirmed the presence of chlorogenic acid and C-glycosylflavonoids (isoorientin and isovitexin) as the major compounds of the CAE.

CONCLUSION

CAE of C. glaziovii exerts significant antiinflammatory and antioxidant activities and this effect can be attributed, at least in part, to the presence of chlorogenic acid and the C-glycosylflavonoids.