Anticonvulsant Effects of Fractions Isolated from Dinoponera quadriceps (Kempt) Ant Venom (Formicidae: Ponerinae)

Natural products, sources of new pharmacological substances, have large chemical diversity and architectural complexity. In this context, some toxins obtained from invertebrate venoms have anticonvulsant effects. Epilepsy is a neurological disorder that affects about 65 million people worldwide, and approximately 30% of cases are resistant to pharmacological treatment. Previous studies from our group show that the denatured venom of the ant Dinoponera quadriceps (Kempt) protects mice against bicuculline (BIC)-induced seizures and death. The aim of this study was to investigate the anticonvulsant activity of compounds isolated from D. quadriceps venom against seizures induced by BIC in mice. Crude venom was fractionated by high-performance liquid chromatography (HPLC) resulting in six fractions referred to as DqTx1-DqTx6. A liquid chromatography-mass spectrometry (LC/MS) analysis revealed a major 431 Da compound in fractions DqTx1 and DqTx2. Fractions DqTx3 and DqTx4 showed a compound of 2451 Da and DqTx5 revealed a 2436 Da compound. Furthermore, the DqTx6 fraction exhibited a major component with a molecular weight of 13,196 Da. Each fraction (1 mg/mL) was microinjected into the lateral ventricle of mice, and the animals were observed in an open field. We did not observe behavioral alterations when the fractions were given alone. Conversely, when the fractions were microinjected 20 min prior to the administration of BIC (21.6 nM), DqTx1, DqTx4, and DqTx6 fractions increased the latency for onset of tonic-clonic seizures. Moreover, all fractions, except DqTx5, increased latency to death. The more relevant result was obtained with the DqTx6 fraction, which protected 62.5% of the animals against tonic-clonic seizures. Furthermore, this fraction protected 100% of the animals from seizure episodes followed by death. Taken together, these findings indicate that compounds from ant venom might be a potential source of new anticonvulsants molecules.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Pró-reitoria de Pesquisa da Universidade Federal do Rio Grande do Norte (PROPESQ/UFRN)Fundaçao de Apoio à Pesquisa do Estado do Rio Grande do Norte (FAPERN)Univ Fed Rio Grande do Norte, Dept Physiol, BR-59078970 Natal, RN, BrazilUniv Sao Paulo, Dept Biol, BR-14040901 Ribeirao Preto, SP, BrazilUniv Fed Sao Paulo, Dept Biophys, BR-04023062 Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Dept Pharmacol, BR-04023062 Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Dept Biosci, BR-11015020 Sao Paulo, SP, BrazilBiophysics Department, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP 04023-062, BrazilPharmacology Department, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP 04023-062, BrazilBiosciences Department, Universidade Federal de São Paulo (UNIFESP), Santos, SP 11015-020, BrazilWeb of Scienc

Passiflora cincinnata

Passiflora cincinnata Masters is a Brazilian native species of passionflower. This genus is known in the American continent folk medicine for its diuretic and analgesic properties. Nevertheless, few studies investigated possible biological effects of P. cincinnata extracts. Further, evidence of antioxidant actions encourages the investigation of possible neuroprotective effects in animal models of neurodegenerative diseases. This study investigates the effect of the P. cincinnata ethanolic extract (PAS) on mice submitted to a progressive model of Parkinson’s disease (PD) induced by reserpine. Male (6-month-old) mice received reserpine (0.1 mg/kg, s.c.), every other day, for 40 days, with or without a concomitant treatment with daily injections of PAS (25 mg/kg, i.p.). Catalepsy, open field, oral movements, and plus-maze discriminative avoidance evaluations were performed across treatment, and immunohistochemistry for tyrosine hydroxylase was conducted at the end. The results showed that PAS treatment delayed the onset of motor impairments and prevented the occurrence of increased catalepsy behavior in the premotor phase. However, PAS administration did not modify reserpine-induced cognitive impairments. Moreover, PAS prevented the decrease in tyrosine hydroxylase immunostaining in the substantia nigra pars compacta (SNpc) induced by reserpine. Taken together, our results suggested that PAS exerted a neuroprotective effect in a progressive model of PD

Effects of regular meditative practice on psychological measures of healthy subjects

Introduction: Meditation is described as a method for improving attention and promoting psychological and emotional stability, presenting favorable results on cognitive functions and stress tolerance as well. Recently, studies have shown differences on psychological measurements between meditators and non-meditators. The aim of this study was to investigate the influence of regular practice of meditation on psychological measures of healthy participants in basal conditions or after experimental stress-induction. Methods: Forty-four healthy participants (20 meditators and 24 non-meditators) were evaluated by inventories of life quality, anxiety, mood, sleep quality, depression, and stress. Furthermore, all participants were submitted to working memory tasks (Hanoy tower and Digit Spam) before and after two stress-induction procedures: Stroop Color-word and Serial Subtraction tests. The research protocol was approved by the institutional ethics committee (204/09 - CEP/UFRN, CAAE 0221.0.051.000-09). Results: Our results showed that meditators presented better inventories scores when compared with non-meditators in parameters such as life quality (score 15.6 versus 14.9, p = 0.04), mood (score 6.0 versus 22.5, p = 0.02), and depression (score 2.5 versus 7.0, p = 0.01). Regarding stress levels, 10 % of meditators (against 37.5% of non-meditators) presented low levels of stress (p = 0.04). Moreover, there was an improvement in performance of meditators (23.3 ± 0.8) in relation to non-meditators (19.0 ± 1.0) on digit span task and in Hanoi tower of meditators (165.2 ± 6.1 ) in relation to non-meditation (224.1 ± 13.1) after stress induction. Conclusion: These findings corroborate other studies showing that meditation can provide an improvement in general quality of life as well as the performance of practitioners in memory tasks

A anticonvulsive fraction from Scaptocosa raptoria (Araneae : Lycosidae) spider venom

Several spider neurotoxins are known to show highly selective effects on nervous tissues. Intracerebral injection into rats of spider venom from Scaptocosa raptoria, prevents seizures induced by convulsant agents. Injection of phenytoin (390 pmol/200 nl), muscimol (90 pmol/200 nl), baclofen (500 pmol/200 nl) into the substantia nigra (SN) pars reticulata, protected rats from convulsions evoked by unilateral focal injection of bicuculline into the area tempestas by 50, 80, and 100%, respectively. Denatured S. raptoria crude venom (4.6 mug, 2.3 mug, and 920 ng/200 nl), when administered into the SN, prevented seizures elicited by bicuculline in the area tempestas by 100, 100, and 87.5%, respectively. the injection into the SN of 160 ng/200 nl of fraction SrTx1 isolated from S. raptoria venom, reduced the magnitude of seizures. This fraction was rechromatographed affording fractions SrTx1.1, SrTx1.2 and SrTx1.3, and they were administered into the SN at doses of 100, 200, and 400 ng/200 nl respectively. Fraction SrTx1.3 protected 50, 85.7, and 100% of the animals against the seizures elicited by bicuculline injected into the area tempestas. This suggests that S. raptoria venom as well as its SrTx1.3 fraction, might be potential sources of new anticonvulsant drugs. (C) 2004 Elsevier Ireland Ltd. All rights reserved.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Univ São Paulo, Fac Philosophy Sci & Literature Ribeirao Preto, Dept Biol, Neurobiol & Venoms Lab, BR-14040901 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biophys, São Paulo, BrazilUniv São Paulo, Fac Pharmaceut Sci Ribeirao Preto, Dept Phys & Chem, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biophys, São Paulo, BrazilCNPq: 141790/00-8Web of Scienc

Influência da prática do yoga sobre os sintomas do climatério

Introdução: Yoga vem sendo praticado há mais de três mil anos e atualmente seu conjunto de técnicas de controle do corpo e da mente tem sido adotado por milhares de pessoas em todo o mundo. Um número crescente de estudos têm atribuído ao yoga benefícios significativos para a reabilitação da saúde do indivíduo. Na mulher, o processo de envelhecimento é marcado pela suspensão da atividade folicular ovariana (menopausa) durante o período do climatério, este caracterizado por uma série de alterações fisiológicas e neuroendócrinas que podem ser acompanhadas por sintomas desconfortáveis e muitas vezes debilitantes. Objetivo: o objetivo deste estudo é investigar os efeitos psicofisiológicos da prática regular do yoga em mulheres que apresentam sintomas do climatério. Método: Noventa mulheres na faixa etária entre 45 e 65 anos, já em menopausa há pelo menos um ano foram divididas em três grupos: Grupo Controle (não participaram das atividades, n = 19), Grupo ginástica suave (2 vezes por semana, n = 31) e Grupo yoga (2 vezes por semana, n = 40). Todas as participantes foram avaliadas antes e ao final do período da intervenção (12 semanas) através dos inventários de síndrome climatérica (MRS: Menopause Rating Scale), depressão (Inventário de Depressão de Beck), estresse (Inventário de Sintomas de Stress para Adultos de Lipp) e medidas de cortisol salivar. O protocolo de pesquisa foi aprovado pelo comitê de ética (582/11/CEP/HUOL, CAAE 09930.000.294-11). Resultados: Nossos resultados mostraram que as voluntárias que praticaram yoga apresentaram redução do índice referente aos sintomas climatéricos após 12 semanas de prática (8,65 ± 1,05) em relação as voluntárias que praticaram ginástica suave (15,13 ± 1,24) e ao grupo controle que não praticou nenhuma atividade (18,58 ± 2,59), esta redução indica uma melhora nos sintomas. Além disso, os grupos ginástica suave (11,65 ± 0,95) e yoga (9,85 ± 1,17) apresentaram uma melhora significativa com relação aos níveis de depressão quando comparados ao grupo controle (18,95 ± 2,66). Após 12 semanas de pratica, os níveis de estresse também foram reduzidos no grupo yoga (0,55 ± 0,14) com relação ao controle (1,74 ± 0,31) e grupo ginástica suave (1,35 ±  0,19). Conclusões: Nossos resultados mostram que a prática deyogapode ser eficazna redução dos sintomas do climatério, além de diminuir os níveis de estresse dessas mulheres, podendo ser considerado como terapia alternativa para o manejo dos sintomas da menopausa

Differential Cortical c-Fos and Zif-268 Expression after Object and Spatial Memory Processing in a Standard or Episodic-Like Object Recognition Task

Episodic memory reflects the capacity to recollect what, where, and when a specific event happened in an integrative manner. Animal studies have suggested that the medial temporal lobe and the medial pre-frontal cortex are important for episodic-like memory (ELM) formation. The goal of present study was to evaluate whether there are different patterns of expression of the immediate early genes c-Fos and Zif-268 in these cortical areas after rats are exposed to object recognition (OR) tasks with different cognitive demands. Male rats were randomly assigned to five groups: home cage control, empty open field (CTR-OF), open field with one object (CTR-OF + Obj), novel OR task, and ELM task and were killed 1 h after the last behavioral procedure. Rats were able to discriminate the objects in the OR task. In the ELM task, rats showed spatial (but not temporal) discrimination of the objects. We found an increase in the c-Fos expression in the dorsal dentate gyrus (DG) and in the perirhinal cortex (PRh) in the OR and ELM groups. The OR group also presented an increase of c-Fos expression in the medial prefrontal cortex (mPFC). Additionally, the OR and ELM groups had increased expression of Zif-268 in the mPFC. Moreover, Zif-268 was increased in the dorsal CA1 and PRh only in the ELM group. In conclusion, the pattern of activation was different in tasks with different cognitive demands. Accordingly, correlation tests suggest the engagement of different neural networks in the tasks used. Specifically, perirhinal-DG co-activation was detected after the what-where memory retrieval, but not after the novel OR task. Both regions correlated with the respective behavioral outcome. These findings can be helpful in the understanding of the neural networks underlying memory tasks with different cognitive demands

Cerebellar Insulin/IGF-1 signaling in diabetic rats: Effects of exercise training

The Diabetes Mellitus (DM) is a chronic disease associated with loss of brain regions such as the cerebellum, increasing the risk of developing neurodegenerative diseases such as Parkinson's disease (PD). In the brain of diabetic and PD organisms the insulin/IGF-1 signaling is altered. Exercise training is an effective intervention for the prevention of neurodegerative diseases since it release neurotrophic factors and regulating insulin/IGF-1 signaling in the brain. This study aimed to evaluate the proteins involved in the insulin/IGF-1 pathway in the cerebellum of diabetic rats subjected to exercise training protocol. Wistar rats were distributed in four groups: sedentary control (SC), trained control (TC), sedentary diabetic (SD) and trained diabetic (TD). Diabetes was induced by Alloxan (ALX) (32 mg/kg b.w.). The training program consisted in swimming 5 days/week, 1 h/day, during 6 weeks, supporting an overload corresponding to 90% of the anaerobic threshold. At the end, cerebellum was extracted to determinate the protein expression of GSK-3 beta, IR beta and IGF-1R and the phosphorylation of beta-amyloid, Tau, ERK1 + ERK2 by Western Blot analysis. All dependent variables were analyzed by one-way analysis of variance with significance level of 5%. Diabetes causes hyperglycemia in both diabetic groupshowever, in TD, there was a reduction in hyperglycemia compared to SD. Diabetes increased Tau and beta-amyloid phosphorylation in both SD and TD groups. Furthermore, aerobic exercise increased ERK1 + ERK2 expression in TC. The data showed that in cerebellum of diabetic rats induced by alloxan there are some proteins expression like Parkinson cerebellum increased, and the exercise training was not able to modulate the expression of these proteins. (C) 2016 Elsevier Ireland Ltd. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Sao Paulo Fed Univ UNIFESP, Dept Biosci, Silva Jardim St 136, Santos, SP, BrazilUniv Estadual Campinas, UNICAMP, Sport Sci Course, Limeira, SP, BrazilSao Paulo State Univ UNESP, Dept Phys Educ, Rio Claro, SP, BrazilCatholic Univ, Ctr Unisalesiano, Dept Phys Educ, Lins, SP, BrazilUniv Ctr Patos De Minas, Dept Phys Educ, Patos De Minas, MG, BrazilSao Paulo Fed Univ UNIFESP, Dept Biosci, Silva Jardim St 136, Santos, SP, BrazilFAPESP: 2010/18257-0CNPq: 142587/2007-9Web of Scienc

Estrogen levels modify scopolamine-induced amnesia in gonadally intact rats

Previous studies suggested that estrogen plays a role in cognitive function by modulating the cholinergic transmission. However, most of the studies dealing with this subject have been conducted using ovariectomized rats. In the present study we evaluated the effects of physiological and supra-physiological variation of estrogen levels on scopolamine-induced amnesia in gonadally intact female rats. We used the plus-maze discriminative avoidance task (PMDAT) in order to evaluate anxiety levels and motor activity concomitantly to the memory performance. In experiment 1, female Wistar rats in each estrous cycle phase received scopolamine (1 mg/kg) or saline i.p. 20 min before the training session in the PMDAT. In experiment 2, rats in diestrus received estradiol valerate (1 mg/kg) or sesame oil i.m., and scopolamine (1 mg/kg) or saline i.p., 45 min and 20 min before the training, respectively. In experiment 3, rats in diestrus received scopolamine (1 mg/kg) or saline i.p. 20 min before the training, and estradiol valerate (1 mg/kg) or sesame oil i.m. immediately after the training session. In all experiments, a test session was performed 24 h later. The main results showed that: (1) scopolamine impaired retrieval and induced anxiolytic and hyperlocomotor effects in all experiments; (2) this cholinergic antagonist impaired acquisition only in animals in diestrus; (3) acute administration of estradiol valerate prevented the learning impairment induced by scopolamine and (4) interfered with memory consolidation process. The results suggest that endogenous variations in estrogen levels across the estrous cycle modulate some aspects of memory mediated by the cholinergic system. Indeed, specifically in diestrus, a stage with low estrogen levels, the impairment produced by scopolamine on the acquisition was counteracted by exogenous administration of the hormone, whereas the posttraining treatment potentiated the negative effects of scopolamine during the consolidation phase of memory