Juliano Ferreira

Universidade Federal de Santa Maria, Santa Maria da Boca do Monte, Rio Grande do Sul, Brazil

Are you Juliano Ferreira?

Claim your profile

Publications (121)397.24 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Vitamin E (vit-E) is a lipophilic antioxidant, and its anti-inflammatory activity is still not full characterized. Thus, our goal was to investigate the anti-inflammatory effect of repeated vit-E treatment in the arthritis induced by the intraplantar injection of complete Freund's adjuvant (CFA). We observed an increase in arthritis scores, interleukin-1β and H2O2 levels, neutrophil and macrophage infiltration, thermal hyperalgesia, mechanical allodynia, and loss of function induced by intraplantar CFA injection. These effects were unaltered after 1 day, partially reversed after 3 days, and inhibited after 9 days after vit-E treatment. Furthermore, the concentration of vit-E was reduced and that of tumor necrosis factor-alpha was increased in the CFA-injected paw. Both effects were reversed from 1 to 9 days after vit-E treatment. However, vit-E treatment did not alter CFA-induced edema at any time. Thus, vit-E treatment produced an anti-inflammatory effect of slow onset in CFA, which demonstrates a disease-modifying drug profile.
    Inflammation 08/2014; · 2.46 Impact Factor
  • Source
  • [Show abstract] [Hide abstract]
    ABSTRACT: Neuropathic pain is a severe painful pathology that is difficult to treat. One option for its management is the continuous intrathecal (i.t.) infusion of ziconotide (the Conus magnus peptide ω-conotoxin MVIIA), which, in addition to being effective, produces serious adverse effects at analgesic doses. Single i.t. administration of Phα1β, a peptide purified from the venom of the spider Phoneutria nigriventer, has antinociceptive effects with a greater therapeutic window than ziconotide in rodents. To further evaluate its analgesic potential, we investigated the antinociceptive and toxic effects of Phα1β after single or continuous i.t. infusion in a rat model of neuropathic pain.
    Anesthesia and analgesia. 05/2014;
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Acute gout attacks produce severe joint pain and inflammation associated with monosodium urate (MSU) crystals leading to oxidative stress production. The transient potential receptor ankyrin 1 (TRPA1) is expressed by a subpopulation of peptidergic nociceptors and via its activation by endogenous reactive oxygen species, including hydrogen peroxide (H2O2), contributes to pain and neurogenic inflammation. The aim of the present study was to investigate the role of TRPA1 in hyperalgesia and inflammation in a model of acute gout attack in rodents. Inflammatory parameters and mechanical hyperalgesia were measured in male Wistar rats, wild-type (Trpa1(+/+)) or TRPA1-deficient (Trpa1(-/-)) male mice. Animals received intra-articular (i.a., ankle) injection of MSU. The role of TRPA1 was assessed by receptor antagonism, gene deletion or expression, sensory fiber defunctionalization, and calcitonin gene-related peptide (CGRP) release. We found that nociceptor defunctionalization, TRPA1 antagonist treatment (via i.a. or oral administration), and TRPA1 gene ablation abated hyperalgesia and inflammatory responses (edema, H2O2 generation, interleukin-1β release, and neutrophil infiltration) induced by i.a. MSU injection. In addition, we showed that MSU evoked generation of H2O2 in synovial tissue which stimulating TRPA1 producing CGRP release and plasma protein extravasation. The MSU-elicited responses were also reduced by the H2O2-detoxifying enzyme catalase and the reducing agent dithiothreitol. TRPA1 activation by MSU challenge-generated H2O2 mediates the entire inflammatory response in an acute gout attack rodent model, thus strengthening the role of the TRPA1 receptor and the H2O2 production as potential targets for treatment of acute gout attacks.
    Free Radical Biology & Medicine 04/2014; · 5.27 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Antipsychotics may cause tardive dyskinesia in humans and orofacial dyskinesia in rodents. Although the dopaminergic system has been implicated in these movement disorders, which involve the basal ganglia, their underlying pathomechanisms remain unclear. CB1 cannabinoid receptors are highly expressed in the basal ganglia, and a potential role for endocannabinoids in the control of basal ganglia-related movement disorders has been proposed. Therefore, this study investigated whether CB1 receptors are involved in haloperidol-induced orofacial dyskinesia in rats. Adult male rats were treated for four weeks with haloperidol decanoate (38mg/kg, intramuscularly - i.m.). The effect of anandamide (6nmol, intracerebroventricularly - i.c.v.) and/or the CB1 receptor antagonist SR141716A (30μg, i.c.v.) on haloperidol-induced vacuous chewing movements (VCMs) was assessed 28days after the start of the haloperidol treatment. Anandamide reversed haloperidol-induced VCMs; SR141716A (30μg, i.c.v.) did not alter haloperidol-induced VCM per se but prevented the effect of anandamide on VCM in rats. These results suggest that CB1 receptors may prevent haloperidol-induced VCMs in rats, implicating CB1 receptor-mediated cannabinoid signaling in orofacial dyskinesia.
    Progress in Neuro-Psychopharmacology and Biological Psychiatry 04/2014; · 3.55 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The transient receptor potential ankyrin 1 (TRPA1) has been identified as a relevant target for the development of novel analgesics. Gallic acid (GA) is a polyphenolic compound commonly found in green tea and various berries and possesses a wide range of biological activities. The goal of this study was to identify GA as a TRPA1 antagonist and observe its antinociceptive effects in different pain models. First, we evaluated the ability of GA to affect cinnamaldehyde-induced calcium influx. Then, we observed the antinociceptive and antiedematogenic effects of GA (3-100 mg/kg) oral administration after the intraplantar (i.pl.) injection of TRPA1 agonists (allyl isothiocyanate, cinnamaldehyde, or hydrogen peroxide-H2O2) in either an inflammatory pain model (carrageenan i.pl. injection) or a neuropathic pain model (chronic constriction injury) in male Swiss mice (25-35 g). GA reduced the calcium influx mediated by TRPA1 activation. Moreover, the oral administration of GA decreased the spontaneous nociception triggered by allyl isothiocyanate, cinnamaldehyde, and H2O2. Carrageenan-induced allodynia and edema were largely reduced by the pretreatment with GA. Moreover, the administration of GA was also capable of decreasing cold and mechanical allodynia in a neuropathic pain model. Finally, GA was absorbed after oral administration and did not produce any detectable side effects. In conclusion, we found that GA is a TRPA1 antagonist with antinociceptive properties in relevant models of clinical pain without detectable side effects, which makes it a good candidate for the treatment of painful conditions.
    Archiv für Experimentelle Pathologie und Pharmakologie 04/2014; · 2.15 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Ultraviolet B (UVB) irradiation mainly affects biological tissues by inducing an increase in reactive oxygen species (ROS) production which leads to deleterious outcomes for the skin, including pain and inflammation. As a protective strategy, many studies have focused on the use of natural products. The aim of this study was to investigate the effects of Aloe saponaria on nociceptive, inflammatory, and oxidative parameters in a model of UVB-induced sunburn in adult male Wistar rats. Sunburned animals were topically treated with vehicle (base cream), 1% silver sulfadiazine (positive control) or A. saponaria (10%) once a day for 6days. UVB-induced nociception (allodynia and hyperalgesia), inflammation (edema and leukocyte infiltration) and oxidative stress (increases in H2O2, protein carbonyl levels and lipid peroxidation and a decrease in non protein thiol content) were reduced by both A. saponaria and sulfadiazine topical treatment. Furthermore, A. saponaria or its constituents aloin and rutin reduced the oxidative stress induced by H2O2 in skin homogenates in vitro. Our results demonstrate that topical A. saponaria treatment displayed anti-nociceptive and anti-inflammatory effects in a UVB-induced sunburn model, and these effects seem to be related to its antioxidant components.
    Journal of photochemistry and photobiology. B, Biology 03/2014; 133C:47-54. · 3.11 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Opioids are standard therapy for the treatment of pain; however, adverse effects limit their use. Voltage-gated calcium channel (VGCC) blockers may be used to increase opioid analgesia, but their effect on opioid-induced side effects is little known. Thus, the goal of this study was to evaluate the action of the peptide Phα1β, a VGCC blocker, on the antinociceptive and adverse effects produced by morphine in mice. A single administration of morphine (3-10 mg/kg) was able to reduce heat nociception as well as decrease gastrointestinal transit. The antinociception caused by a single injection of morphine was slightly increased by an intrathecal injection (i.t.) of Phα1β (30 pmol/site). Repeated treatment with morphine caused tolerance, hyperalgesia, withdrawal syndrome and constipation and the Phα1β (0.1-30 pmol/site, i.t.) was able to reverse these effects. Finally, the effects produced by the native form of Phα1β were fully mimicked by a recombinant version of this peptide. Taken together, these data show that Phα1β was effective in potentiating the analgesia caused by a single dose of morphine as well as in reducing tolerance and the adverse effects induced by repeated administration of morphine, indicating its potential use as an adjuvant drug in combination with opioids. This article presents pre-clinical evidences for an useful adjuvant drug in opioid treatment. Phα1β, a peptide calcium channel blocker, could be used not only to potentate morphine analgesia, but also to reduce the adverse effects caused by repeated administration of morphine.
    The journal of pain: official journal of the American Pain Society 03/2014; · 3.78 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: This study investigated the effects of Phα1β, pregabalin and diclofenac using an animal model of fibromyalgia (FM). Repeated administration of reserpine (0.25 mg/kg sc) once daily for three consecutive days significantly decreased thermal hyperalgesia, mechanical allodynia, and dopamine and serotonin content in the brain on the 4th day. Phα1β and pregabalin treatment completely reverted the mechanical allodynia and thermal hyperalgesia induced by reserpine treatment on the 4th day, but diclofenac was ineffective. Reserpine treatment significantly increased the immobility time in the forced swim test, which is indicative of depression in the animals. Phα1β, but not pregabalin, reduced the immobility time (56%), suggesting that Phα1β may control persistent pathological pain in FM.
    Toxicon 01/2014; · 2.92 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Abstract Background: Interest in pecan (Carya illinoensis) nut shells, a by-product of the nut industry, has increased due to its anti-inflammatory and antioxidant activities. The goal of this study was to evaluate the antinociceptive and antiedematogenic activity and the mechanisms of the pecan shell aqueous extract (AE). Methods: First, we performed fingerprinting of C. illinoensis AE. The antinociceptive and antiedematogenic effects of AE intragastric (i.g.) administration in mice (male Swiss mice 20-30 g) were evaluated using the acetic acid test or after subcutaneous (s.c.) paw injection of diverse transient receptor potential ankyrin 1 (TRPA1) agonists, including hydrogen peroxide (H2O2), allyl isothiocyanate, or cinnamaldehyde. We also observed AE antinociceptive and antiedematogenic effects after carrageenan s.c. paw injection and measured H2O2 production. Moreover, we observed the development of adverse effects after AE i.g. treatment. Results: The high-performance liquid chromatography fingerprinting of AE showed the presence of rutin. AE or rutin i.g. treatment produced antinociception in the acetic acid test and reduced the nociception and edema mediated by H2O2 s.c. hind paw injection or nociception induced by other TRPA1 agonists. Moreover, AE or rutin reduced the hyperalgesia, edema, and H2O2 production induced by carrageenan s.c. paw injection. No motor, gastric, or toxicological alterations were observed after AE administration. Conclusions: Collectively, the present results show that AE and its constituent rutin produced antinociceptive and antiedematogenic action in models of acute and persistent inflammatory nociception and it seems to be related to the inhibition of TRPA1 receptor activation.
    Journal of basic and clinical physiology and pharmacology. 01/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Opioids are standard therapy for the treatment of pain; however, adverse effects limit their use. Voltage-gated calcium channel (VGCC) blockers may be used to increase opioid analgesia, but their effect on opioid-induced side effects is little known. Thus, the goal of this study was to evaluate the action of the peptide Phα1β, a VGCC blocker, on the antinociceptive and adverse effects produced by morphine in mice. A single administration of morphine (3-10 mg/kg) was able to reduce heat nociception as well as decrease gastrointestinal transit. The antinociception caused by a single injection of morphine was slightly increased by an intrathecal injection (i.t.) of Phα1β (30 pmol/site). Repeated treatment with morphine caused tolerance, hyperalgesia, withdrawal syndrome and constipation and the Phα1β (0.1-30 pmol/site, i.t.) was able to reverse these effects. Finally, the effects produced by the native form of Phα1β were fully mimicked by a recombinant version of this peptide. Taken together, these data show that Phα1β was effective in potentiating the analgesia caused by a single dose of morphine as well as in reducing tolerance and the adverse effects induced by repeated administration of morphine, indicating its potential use as an adjuvant drug in combination with opioids. Perspective This article presents pre-clinical evidences for an useful adjuvant drug in opioid treatment. Phα1β, a peptide calcium channel blocker, could be used not only to potentate morphine analgesia, but also to reduce the adverse effects caused by repeated administration of morphine.
    The Journal of Pain. 01/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Pain is the most common complaint in the medical field and the identification of novel compounds that can effectively treat painful states without causing side effects remains a major challenge in biomedical research. The aim of the present study is to investigate the antinociceptive effect of 3-(4-fluorophenyl)-5-trifluoromethyl-1H-1-tosylpyrazole (FTosPz) in models of pathological pain in mice and compare these effects with those produced by the Celecoxib. FTosPz (100-500μmol/kg) or Celecoxib (26-260μmol/kg) were administrated orally. The administration of either FTosPz or Celecoxib reduced the hyperalgesia but not the edema or leukocyte infiltration that was caused by Complete Freund's Adjuvant (CFA), used as an arthritis model. Oral administration of both FTosPz and Celecoxib also attenuated the postoperative hyperalgesia as well as the hyperalgesia caused by partial sciatic nerve ligation, used as a neuropathic pain model. FTosPz and Celecoxib produced antinociceptive effects without altering the locomotor activity of animals. Furthermore, FTosPz neither altered AST/ALT enzyme activity nor the urea/creatinine levels. Still, the FTosPz did not alter the COX-1 and COX-2 enzyme activities. Thus, FTosPz is an interesting prototype for the development of novel analgesic drugs.
    Pharmacology Biochemistry and Behavior 01/2014; · 2.61 Impact Factor
  • Advances in Free Radical Biology & Medicine 01/2014; 72:200–209.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Antipsychotics may cause tardive dyskinesia in humans and orofacial dyskinesia in rodents. Although the dopaminergic system has been implicated in these movement disorders, which involve the basal ganglia, their underlying pathomechanisms remain unclear. CB1 cannabinoid receptors are highly expressed in the basal ganglia, and a potential role for endocannabinoids in the control of basal ganglia-related movement disorders has been proposed. Therefore, this study investigated whether CB1 receptors are involved in haloperidol-induced orofacial dyskinesia in rats. Adult male rats were treated for four weeks with haloperidol decanoate (38 mg/kg, intramuscularly – i.m.). The effect of anandamide (6 nmol, intracerebroventricularly - i.c.v.) and/or the CB1 receptor antagonist SR141716A (30 μg, i.c.v.) on haloperidol-induced vacuous chewing movements (VCMs) was assessed 28 days after the start of the haloperidol treatment. Anandamide reversed haloperidol-induced VCMs; SR141716A (30 μg, i.c.v.) did not alter haloperidol-induced VCM per se but prevented the effect of anandamide on VCM in rats. These results suggest that CB1 receptors may prevent haloperidol-induced VCMs in rats, implicating CB1 receptor-mediated cannabinoid signaling in orofacial dyskinesia.
    Progress in Neuro-Psychopharmacology and Biological Psychiatry 01/2014; · 3.55 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: There are evidences indicating the role of kinins in pathophysiology of traumatic brain injury, but little is known about their action on memory deficits. Our aim was to establish the role of bradykinin receptors B1 (B1R) and B2 (B2R) on the behavioral, biochemical, and histologic features elicited by moderate lateral fluid percussion injury (mLFPI) in mice. The role of kinin B1 and B2 receptors in brain damage, neuromotor, and cognitive deficits induced by mLFPI, was evaluated by means of subcutaneous injection of B2R antagonist (HOE-140; 1 or 10 nmol/kg) or B1R antagonist (des-Arg9-[Leu8]-bradykinin (DAL-Bk; 1 or 10 nmol/kg) 30 min and 24 h after brain injury. Brain damage was evaluated in the cortex, being considered as lesion volume, inflammatory, and oxidative damage. The open field and elevated plus maze tests were performed to exclude the nonspecific effects on object recognition memory test. Our data revealed that HOE-140 (10 nmol/kg) protected against memory impairment. This treatment attenuated the brain edema, interleukin-1β, tumor necrosis factor-α, and nitric oxide metabolites content elicited by mLFPI. Accordingly, HOE-140 administration protected against the increase of nicotinamide adenine dinucleotide phosphate oxidase activity, thiobarbituric-acid-reactive species, protein carbonylation generation, and Na(+) K(+) ATPase inhibition induced by trauma. Histologic analysis showed that HOE-140 reduced lesion volume when analyzed 7 days after brain injury. This study suggests the involvement of the B2 receptor in memory deficits and brain damage caused by mLFPI in mice.
    Psychopharmacology 11/2013; · 4.06 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objective Gout is a common cause of inflammatory arthritis and is provoked by the accumulation of monosodium urate (MSU) crystals. However, the underlying mechanisms of the pain associated with acute attacks of gout are poorly understood. The aim of this study was to evaluate the role of transient receptor potential ankyrin 1 (TRPA-1) and TRPA-1 stimulants, such as H2O2, in a rodent model of MSU-induced inflammation. MethodsMSU or H2O2 was injected into the hind paws of rodents or applied in cultured sensory neurons, and the intracellular calcium response was measured in vitro. Inflammatory or nociceptive responses in vivo were evaluated using pharmacologic, genetic, or biochemical tools and methods. ResultsTRPA-1 antagonism, TRPA-1 gene deletion, or pretreatment of peptidergic TRP-expressing primary sensory neurons with capsaicin markedly decreased MSU-induced nociception and edema. In addition to these neurogenic effects, MSU increased H2O2 levels in the injected tissue, an effect that was abolished by the H2O2-detoxifying enzyme catalase. H2O2, but not MSU, directly stimulated sensory neurons through the activation of TRPA-1. The nociceptive responses evoked by MSU or H2O2 injection were attenuated by the reducing agent dithiothreitol. In addition, MSU injection increased the expression of TRPA-1 and TRP vanilloid channel 1 (TRPV-1) and also enhanced cellular infiltration and interleukin-1β levels, and these effects were blocked by TRPA-1 antagonism. Conclusion Our results suggest that MSU injection increases tissue H2O2, thereby stimulating TRPA-1 on sensory nerve endings to produce inflammation and nociception. TRPV-1, by a previously unknown mechanism, also contributes to these responses.
    Arthritis & Rheumatology 11/2013; 65(11). · 7.48 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objective. The aim of the present study was to investigate the participation of TRPV1 in an acute gout attack model.Methods. Experiments were conducted to evaluate the participation of TRPV1 in the nociceptive and inflammatory responses (oedema, plasma extravasation, leucocyte infiltration and also IL-1β production) triggered by IA (ankle) administration of monosodium urate (MSU) in rats using selective antagonist TRPV1 receptor, defunctionalization of sensory fibres and increased immunoreactivity. We have also analysed the inflammatory response. The participation of mast cells in the MSU-induced nociception and inflammation was evaluated using a mast cell stabilizer and a mast cell degranulator compound.Results. We observed that MSU (1.25 mg/site) injected into the rat ankle joint elicited ongoing pain-like behaviour, hyperalgesia, allodynia and articular oedema as well as plasma extravasation, leucocyte infiltration and IL-1β production in lavage fluid. All of these events were inhibited by the co-administration of the selective TRPV1 receptor antagonist SB366791 (10 nmol/site). MSU crystals also increased the immunoreactivity of the TRPV1 receptor in the articular tissue of injected animals. Furthermore, the defunctionalization of TRPV1-positive sensory neurons also significantly reduced MSU-induced ongoing pain-like behaviour, hyperalgesia and oedema.Conclusion. Thus we demonstrate that TRPV1 acts on sensory neurons and plays a relevant role in the nociception and inflammation induced by IA MSU, indicating it as a potential target to treat acute gout attacks.
    Rheumatology (Oxford, England) 10/2013; · 4.24 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The treatment with the chemotherapeutic agent paclitaxel produces a painful peripheral neuropathy, and is associated with an acute pain syndrome in a clinically significant number of patients. However, no standard therapy has been established to manage the acute pain or the chronic neuropathic pain related to paclitaxel. In the present study, we evaluated the analgesic potential of two N-type voltage-gated calcium channel (VGCC) blockers, ω-conotoxin MVIIA and Phα1β, on acute and chronic pain induced by paclitaxel. Adult male rats were treated with four intraperitoneal injections of paclitaxel (1+1+1+1mg/kg, in alternate days) and the development of mechanical hyperalgesia was evaluated 24hours (acute painful stage) or 15days (chronic painful stage) after the first paclitaxel injection. Not all animals showed mechanical hyperalgesia 24h after the first paclitaxel injection, but those that showed developed a more intense mechanical hyperalgesia at the chronic painful stage. Intrathecal administration (i.t.) of ω-conotoxin MVIIA (3-300 pmol/site) or Phα1β (10-300 pmol/site) reduced the mechanical hyperalgesia either at the acute or at the chronic painful stage induced by paclitaxel. When administered at the acute painful stage, ω-conotoxin MVIIA (300 pmol/site, i.t.) and Phα1β (300 pmol/site, i.t.) prevented the worsening of chronic mechanical hyperalgesia. Furthermore, Phα1β (30-300 pmol/site, i.t.) elicited less adverse effects than ω-conotoxin MVIIA (10-300 pmol/site, i.t.). Taken together, our data evidence the involvement of N-type VGCC in pain sensitization induced by paclitaxel and point out the potential of Phα1β as a safer alternative than ω-conotoxin MVIIA to treat the pain related to paclitaxel.
    Pharmacology Biochemistry and Behavior 10/2013; · 2.61 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Traumatic brain injury (TBI) is a devastating disease that commonly causes persistent mental disturbances and cognitive deficits. Although studies have indicated that overproduction of free radicals, especially superoxide (O2(-)) derived from Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is a common underlying mechanism of pathophysiology of TBI, little information is available regarding the role of apocynin, an NADPH oxidase inhibitor, in neurological consequences of TBI. Therefore, the present study evaluated the therapeutic potential of apocynin for treatment of inflammatory and oxidative damage, in addition to determining its action on neuromotor and memory impairments caused by moderate fluid percussion injury in mice (mLFPI). Statistical analysis revealed that apocynin (5 mg/kg), when injected subcutaneously (s.c.) 30 min and 24 h after injury, had no effect on neuromotor deficit and brain edema, however it provided protection against mLFPI-induced object recognition memory impairment 7 days after neuronal injury. The same treatment protected against mLFPI-induced IL-1β, TNF-α, nitric oxide metabolite content (NOx) 3 and 24 hours after neuronal injury. Moreover, apocynin treatment reduced oxidative damage (protein carbonyl, lipoperoxidation) and was effective against mLFPI-induced Na(+)K(+)-ATPase activity inhibition. The present results were accompanied by effective reduction in lesion volume when analyzed 7 days after neuronal injury. These data suggest that superoxide (O2(-)) derived from NADPH oxidase can contribute significantly to cognitive impairment, and that the post injury treatment with specific NADPH oxidase inhibitors, such as apocynin, may provide a new therapeutic approach to the control of neurological disabilities induced by TBI.
    Neurochemistry International 09/2013; · 2.66 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Alzheimer's disease (AD) is biochemically characterized by the occurrence of extracellular deposits of amyloid beta peptide (Aβ) and intracellular deposits of the hyperphosphorylated tau protein, which are causally related to the pathological hallmarks senile plaques and neurofibrillary tangles. Monoamine oxidase B (MAO-B) activity, involved in the oxidation of biogenic monoamines, is particularly high around the senile plaques and increased in AD patients in middle to late clinical stages of the disease. Selegiline is a selective and irreversible MAO-B inhibitor and, although clinical trials already shown the beneficial effect of selegiline on cognition of AD patients, its mechanism of action remains to be elucidated. Therefore, we first investigated whether selegiline reverses the impairment of object recognition memory induced by Aβ25-35 in mice, an established model of AD. In addition, we investigated whether selegiline alters MAO-B and MAO-A activities in the hippocampus, perirhinal and remaining cerebral cortices of Aβ25-35-injected male mice. Acute (1 and 10 mg/kg, p.o., immediately post-training) and subchronic (10 mg/kg, p.o., seven days after Aβ25-35 injection and immediately post-training) administration of selegiline reversed the cognitive impairment induced by Aβ25-35 (3 nmol, i.c.v.). Acute administration of selegiline (1 mg/kg, p.o.) in combination with Aβ25-35 (3 nmol) decreased MAO-B activity in the perirhinal and remaining cerebral cortices. Acute administration of selegiline (10 mg/kg, p.o.) decreased MAO-B activity in hippocampus, perirhinal and remaining cerebral cortices, regardless of Aβ25-35 or Aβ35-25 treatment. MAO-A activity was not altered by selegiline or Aβ25-35. In summary, the current findings further support a role for cortical monoaminergic transmission in the cognitive deficits observed in AD.
    Neurochemical Research 09/2013; · 2.13 Impact Factor

Publication Stats

1k Citations
397.24 Total Impact Points

Institutions

  • 2006–2014
    • Universidade Federal de Santa Maria
      • • Centre of Natural and Exact Sciences (CCNE)
      • • Department of Chemistry
      • • Department of Chemical Engineering (DEQ)
      • • Department of Methods and Sports Techniques (DMTD)
      Santa Maria da Boca do Monte, Rio Grande do Sul, Brazil
  • 2013
    • Santa Casa de Belo Horizonte
      Cidade de Minas, Minas Gerais, Brazil
    • Universidade Federal de Sergipe
      Aracaju, Sergipe, Brazil
    • Federal Technological University of Parana
      Curityba, Paraná, Brazil
  • 2008–2013
    • Federal University of Minas Gerais
      • • Faculdade de Medicina
      • • Departamento de Farmacologia
      Cidade de Minas, Minas Gerais, Brazil
    • Universidade Federal do Rio Grande do Sul
      Pôrto de São Francisco dos Casaes, Rio Grande do Sul, Brazil
  • 1999–2008
    • Federal University of Santa Catarina
      • • Centro de Ciências Biológicas (CCB)
      • • Departamento de Farmacologia
      Florianópolis, Estado de Santa Catarina, Brazil