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Renin-Angiotensin System (RAS) is a peptidergic system, canonically known for its role in blood pressure regulation. Furthermore, a non-canonical RAS regulates pathophysiological phenomena, such as inflammation since it consists of two main axes: the pro-inflammatory renin/(pro)renin receptor ((P)RR) axis, and the anti-inflammatory angiotensin-converting enzyme 2 (ACE2)/Angiotensin-(1-7) (Ang-(1-7))/Mas Receptor (MasR) axis. Few phytochemicals have shown to exert angiotensinergic and anti-inflammatory effects through some of these axes; nevertheless, anti-inflammatory drugs, such as phytocannabinoids have not been studied regarding this subject. Among phytocannabinoids, ß-Caryophyllene stands out as a dietary phytocannabinoid with antiphlogistic activity that possess a unique sesquiterpenoid structure. Although its cannabinergic effect has been studied, its angiotensinergic effect reminds underexplored. This study aims to explore the angiotensinergic effect of ß-Caryophyllene on inflammation and stress at a systemic level. After intranasal Lipopolysaccharide (LPS) installation and oral treatment with ß-Caryophyllene, the concentration and activity of key RAS elements in the serum, such as Renin, ACE2 and Ang-(1-7), along with the stress hormone corticosterone and pro/anti-inflammatory cytokines, were measured in mice serum. The results show that ß-Caryophyllene treatment modified RAS levels by increasing Renin and Ang-(1-7), alongside the reduction of pro-inflammatory cytokines and corticosterone levels. These results indicate that ß-Caryophyllene exhibits angiotensinergic activity in favor of anti-inflammation.
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Angiotensina I , Inflamação , Lipopolissacarídeos , Sesquiterpenos Policíclicos , Sistema Renina-Angiotensina , Animais , Sesquiterpenos Policíclicos/farmacologia , Inflamação/metabolismo , Inflamação/tratamento farmacológico , Masculino , Camundongos , Sistema Renina-Angiotensina/efeitos dos fármacos , Angiotensina I/metabolismo , Sesquiterpenos/farmacologia , Anti-Inflamatórios/farmacologia , Fragmentos de Peptídeos/metabolismoRESUMO
Vascular endothelial growth factor (VEGF) exerts neuroprotective or proinflammatory effects, depending on what VEGF forms (A-E), receptor types (VEGFR1-3), and intracellular signaling pathways are involved. Neonatal monosodium glutamate (MSG) treatment triggers neuronal death by excitotoxicity, which is commonly involved in different neurological disorders, including neurodegenerative diseases. This study was designed to evaluate the effects of VEGFR-2 inhibition on neuronal damage triggered by excitotoxicity in the cerebral motor cortex (CMC) and hippocampus (Hp) after neonatal MSG treatment. MSG was administered at a dose of 4 g/kg of body weight (b.w.) subcutaneously on postnatal days (PD) 1, 3, 5, and 7, whereas the VEGFR-2 inhibitor SU5416 was administered at a dose of 10 mg/kg b.w. subcutaneously on PD 5 and 7, 30 min before the MSG treatment. Neuronal damage was assessed using hematoxylin and eosin staining, fluoro-Jade staining, and TUNEL assay. Additionally, western blot assays for some proteins of the VEGF-A/VEGFR-2 signaling pathway (VEGF-A, VEGFR-2, PI3K, Akt, and iNOS) were carried out. All assays were performed on PD 6, 8, 10, and 14. Inhibition of VEGFR-2 signaling by SU5416 increases the neuronal damage induced by neonatal MSG treatment in both the CMC and Hp. Moreover, neonatal MSG treatment increased the expression levels of the studied VEGF-A/VEGFR-2 signaling pathway proteins, particularly in the CMC. We conclude that VEGF-A/VEGFR-2 signaling pathway activation could be part of the neuroprotective mechanisms that attempt to compensate for neuronal damage induced by neonatal MSG treatment and possibly also in other conditions involving excitotoxicity.
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Hipocampo , Córtex Motor , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Hipocampo/efeitos dos fármacos , Córtex Motor/efeitos dos fármacos , Glutamato de Sódio/toxicidade , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , AnimaisRESUMO
Spatial learning and memory enables individuals to orientate themselves in an external environment. Synaptic stimulation of dendritic spines on hippocampal place cells underlies adaptive cognitive performance, inducing plastic changes such as spinogenesis, pruning and structural interconversion. Such plastic changes are driven by complex molecular machinery that relies on several actin cytoskeleton-associated proteins (ACAP's), these interacting with actin filaments in the postsynaptic density to guide the conformational changes to spines in accordance with the synaptic information they receive. However, the specific dynamics of the plastic changes in spines driven by ACAP's are poorly understood. Adult rats exhibit efficient allocentric reference memory 30 days after training in a spatial learning paradigm in the Morris water maze. A Golgi study revealed this behavior to be associated with a reduction in both spine density and in mushroom spines, as well as a concomitant increase in thin spines. These changes were accompanied by the overexpression of mRNA encoding ß-actin, Spinophilin and Cortactin, whilst the expression of Profilin, α-actinin, Drebrin, Synaptopodin and Myosin decreased. By contrast, no changes were evident in Cofilin, Gelsolin and Arp2/3 mRNA. From this analysis, it appears that neither spinogenesis nor new mushroom spines are necessary for long-term spatial information retrieval, while thin spines could be potentiated to retrieve pre-learned spatial information. Further studies that focus on the signaling pathways and their related molecules may shed further light on the molecular dynamics of the plastic changes to dendritic spines that underlie cognitive performance, both under normal and pathological conditions.
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Região CA1 Hipocampal/fisiologia , Proteínas do Citoesqueleto/fisiologia , Espinhas Dendríticas/fisiologia , Memória de Longo Prazo/fisiologia , Plasticidade Neuronal , Animais , Masculino , Ratos Sprague-Dawley , Aprendizagem Espacial/fisiologia , Memória Espacial/fisiologiaRESUMO
BACKGROUND: The correlations of genotypic and phenotypic tests with treatment, clinical history and the significance of mutations in viruses of HIV-infected patients are used to establish resistance mutations to protease inhibitors (PIs). Emerging mutations in human immunodeficiency virus type 1 (HIV-1) protease confer resistance to PIs by inducing structural changes at the ligand interaction site. The aim of this study was to establish an in silico structural relationship between natural HIV-1 polymorphisms and unusual HIV-1 mutations that confer resistance to PIs. RESULTS: Protease sequences isolated from 151 Mexican HIV-1 patients that were naïve to, or subjected to antiretroviral therapy, were examined. We identified 41 unrelated resistance mutations with a prevalence greater than 1%. Among these mutations, nine exhibited positive selection, three were natural polymorphisms (L63S/V/H) in a codon associated with drug resistance, and six were unusual mutations (L5F, D29V, L63R/G, P79L and T91V). The D29V mutation, with a prevalence of 1.32% in the studied population, was only found in patients treated with antiretroviral drugs. Using in silico modelling, we observed that D29V formed unstable protease complexes when were docked with lopinavir, saquinavir, darunavir, tipranavir, indinavir and atazanavir. CONCLUSIONS: The structural correlation of natural polymorphisms and unusual mutations with drug resistance is useful for the identification of HIV-1 variants with potential resistance to PIs. The D29V mutation likely confers a selection advantage in viruses; however, in silico, presence of this mutation results in unstable enzyme/PI complexes, that possibly induce resistance to PIs.
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Farmacorresistência Viral/genética , Inibidores da Protease de HIV/farmacologia , Protease de HIV/genética , HIV-1/enzimologia , HIV-1/genética , Sulfato de Atazanavir , Sequência de Bases , Darunavir , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Protease de HIV/química , Inibidores da Protease de HIV/uso terapêutico , HIV-1/efeitos dos fármacos , Humanos , Masculino , Simulação de Acoplamento Molecular , Dados de Sequência Molecular , Mutação , Oligopeptídeos/farmacologia , Oligopeptídeos/uso terapêutico , Fenótipo , Polimorfismo Genético , Piridinas/farmacologia , Piridinas/uso terapêutico , Pironas/farmacologia , Pironas/uso terapêutico , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêuticoRESUMO
High-content screening led to the identification of the N-isobutylamide guineensine from Piper nigrum as novel nanomolar inhibitor (EC50=290nM) of cellular uptake of the endocannabinoid anandamide (AEA). Noteworthy, guineensine did not inhibit endocannabinoid degrading enzymes fatty acid amide hydrolase (FAAH) or monoacylglycerol lipase (MAGL) nor interact with cannabinoid receptors or fatty acid binding protein 5 (FABP5), a major cytoplasmic AEA carrier. Activity-based protein profiling showed no inhibition of serine hydrolases. Guineensine also inhibited the cellular uptake of 2-arachidonoylglycerol (2-AG). Preliminary structure-activity relationships between natural guineensine analogs indicate the importance of the alkyl chain length interconnecting the pharmacophoric isobutylamide and benzodioxol moieties for AEA cellular uptake inhibition. Guineensine dose-dependently induced cannabimimetic effects in BALB/c mice shown by strong catalepsy, hypothermia, reduced locomotion and analgesia. The catalepsy and analgesia were blocked by the CB1 receptor antagonist rimonabant (SR141716A). Guineensine is a novel plant natural product which specifically inhibits endocannabinoid uptake in different cell lines independent of FAAH. Its scaffold may be useful to identify yet unknown targets involved in endocannabinoid transport.
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Alcenos/farmacologia , Analgésicos/farmacologia , Ácidos Araquidônicos/metabolismo , Endocanabinoides/metabolismo , Compostos Heterocíclicos com 2 Anéis/farmacologia , Alcamidas Poli-Insaturadas/metabolismo , Alcenos/administração & dosagem , Alcenos/química , Amidoidrolases/metabolismo , Analgésicos/administração & dosagem , Animais , Transporte Biológico/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Encéfalo/metabolismo , Antagonistas de Receptores de Canabinoides/farmacologia , Catalepsia/induzido quimicamente , Relação Dose-Resposta a Droga , Proteínas de Ligação a Ácido Graxo , Glicerídeos/metabolismo , Compostos Heterocíclicos com 2 Anéis/administração & dosagem , Compostos Heterocíclicos com 2 Anéis/química , Humanos , Hipotermia/induzido quimicamente , Locomoção/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Monoacilglicerol Lipases/metabolismo , Proteínas de Neoplasias , Piper/química , Piperidinas/farmacologia , Pirazóis/farmacologia , Receptores de Canabinoides/metabolismo , Rimonabanto , Serina Endopeptidases , Relação Estrutura-Atividade , Células U937RESUMO
Over time, several studies have been conducted to demonstrate the functions of the neurotransmitter 5-hydroxytryptamine (5-HT), better known as serotonin. This neurotransmitter is associated with the modulation of various social and physiological behaviors, and its dysregulation has consequences at the behavioral level, leading to various neurophysiological disorders. Disorders such as anxiety, depression, schizophrenia, epilepsy, sexual disorders, and eating disorders, have been closely linked to variations in 5-HT concentrations and modifications in brain structures, including the raphe nuclei (RN), prefrontal cortex, basal ganglia, hippocampus, and hypothalamus, among others. The involvement of ß-arrestin proteins has been implicated in the modulation of the serotonergic receptor response, as well as the activation of different signaling pathways related to the serotonergic system, this is particularly relevant in depressive disorders. This review will cover the implications of alterations in 5-HT receptor expression in depressive disorders in one hand and how ß-arrestin proteins modulate the response mediated by these receptors in the other hand.
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Receptores de Serotonina , beta-Arrestinas , Humanos , beta-Arrestinas/metabolismo , Receptores de Serotonina/metabolismo , Serotonina/metabolismo , Transdução de Sinais/fisiologia , Transtorno Depressivo/metabolismo , Transtorno Depressivo/fisiopatologia , Encéfalo/metabolismo , Depressão/metabolismoRESUMO
Parkinson's disease (PD) is a neurodegenerative disorder characterized by alterations in motor capacity resulting from a decrease in the neurotransmitter dopamine due to the selective death of dopaminergic neurons of the nigrostriatal pathway. Unfortunately, conventional pharmacological treatments fail to halt disease progression; therefore, new therapeutic strategies are needed, and currently, some are being investigated. The endocannabinoid system (ECS), highly expressed in the basal ganglia (BG) circuit, undergoes alterations in response to dopaminergic depletion, potentially contributing to motor symptoms and the etiopathogenesis of PD. Substantial evidence supports the neuroprotective role of the ECS through various mechanisms, including anti-inflammatory, antioxidative, and antiapoptotic effects. Therefore, the ECS emerges as a promising target for PD treatment. This review provides a comprehensive summary of current clinical and preclinical evidence concerning ECS alterations in PD, along with potential pharmacological targets that may exert the protection of dopaminergic neurons.
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Obsessive-compulsive disorder (OCD) is a mental affliction characterized by compulsive behaviors often manifested in intrusive thoughts and repetitive actions. The quinpirole model has been used with rats to replicate compulsive behaviors and study the neurophysiological processes associated with this pathology. Several changes in the dendritic spines of the medial prefrontal cortex (mPFC) and dorsolateral striatum (DLS) have been related to the occurrence of compulsive behaviors. Dendritic spines regulate excitatory synaptic contacts, and their morphology is associated with various brain pathologies. The present study was designed to correlate the occurrence of compulsive behaviors (generated by administering the drug quinpirole) with the morphology of the different types of dendritic spines in the mPFC and DLS. A total of 18 male rats were used. Half were assigned to the experimental group, the other half to the control group. The former received injections of quinpirole, while the latter rats were injected with physiological saline solution, for 10 days in both cases. After the experimental treatment, the quinpirole rats exhibited all the parameters indicative of compulsive behavior and a significant correlation with the density of stubby and wide neckless spines in both the mPFC and DLS. Dendritic spines from both mPFC and DLS neurons showed plastic changes correlatively with the expression of compulsive behavior induced by quinpirole. Further studies are suggested to evaluate the involvement of glutamatergic neurotransmission in the neurobiology of OCD.
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Background: Cardiorenal syndrome (CRS) type 4 is prevalent among the chronic kidney disease (CKD) population, with many patients dying from cardiovascular complications. However, limited data regarding cardiac transcriptional changes induced early by CKD is available. Methods: We used a murine unilateral ureteral obstruction (UUO) model to evaluate renal damage, cardiac remodeling, and transcriptional regulation at 21 days post-surgery through histological analysis, RT-qPCR, RNA-seq, and bioinformatics. Results: UUO leads to significant kidney injury, low uremia, and pathological cardiac remodeling, evidenced by increased collagen deposition and smooth muscle alpha-actin 2 expression. RNA-seq analysis identified 76 differentially expressed genes (DEGs) in UUO hearts. Upregulated DEGs were significantly enriched in cell cycle and cell division pathways, immune responses, cardiac repair, inflammation, proliferation, oxidative stress, and apoptosis. Gene Set Enrichment Analysis further revealed mitochondrial oxidative bioenergetic pathways, autophagy, and peroxisomal pathways are downregulated in UUO hearts. Vimentin was also identified as an UUO-upregulated transcript. Conclusions: Our results emphasize the relevance of extensive transcriptional changes, mitochondrial dysfunction, homeostasis deregulation, fatty-acid metabolism alterations, and vimentin upregulation in CRS type 4 development.
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Leachate from municipal solid waste is a mixture of xenobiotics capable of contaminating bodies of water and causing damage to the health of living beings that inhabit or consume contaminated water. A previous study revealed the presence of heavy metals in Urban Solid Waste Transfer Station (USWTS) leachate above the permissible national and international limits. In the present study, we demonstrate that subchronic oral administration (5 and 25 % v/v) of leachate to male Wistar rats caused changes in the immunoreactivity of the glial markers: GFAP and Iba-1, accompanied by an increase in the expression of caspase-3, and a decrease in the expression of the NeuN protein. Results indicate that the heavy metals present in the leachate induced neuronal loss in the prefrontal cortex, suggesting that these contaminants can cause neurological problems in mammals that consume surface water with xenobiotics, since the leachate could contaminate water bodies and underground water.
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Decreased Choline Acetyltransferase (ChAT) brain level is one of the main biochemical disorders in Alzheimer's Disease (AD). In rodents, recent data show that the CHAT gene can be regulated by a neural restrictive silencer factor (NRSF). The aim of the present work was to evaluate the gene and protein expression of CHAT and NRSF in frontal, temporal, entorhinal and parietal cortices of AD patient brains. Four brains from patients with AD and four brains from subjects without dementia were studied. Cerebral tissues were obtained and processed by the guanidine isothiocyanate method for RNA extraction. CHAT and NRSF gene and protein expression were determined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. CHAT gene expression levels were 39% lower in AD patients as compared to the control group (p < 0.05, U test). ChAT protein levels were reduced by 17% (p = 0.02, U test). NRSF gene expression levels were 86% higher in the AD group (p = 0.001, U test) as compared to the control group. In the AD subjects, the NRSF protein levels were 57% higher (p > 0.05, U test) than in the control subjects. These findings suggest for the first time that in the brain of AD patients high NRSF protein levels are related to low CHAT gene expression levels.
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Sexual experience improves copulatory performance in male rats. Copulatory performance has been associated with dendritic spines density in the medial prefrontal cortex (mPFC) and nucleus accumbens (NAcc), structures involved in the processing of sexual stimuli and the manifestation of sexual behavior. Dendritic spines modulate excitatory synaptic contacts, and their morphology is associated with the ability to learn from experience. This study was designed to determine the effect of sexual experience on the density of different types or shapes of dendritic spines in the mPFC and NAcc of male rats. A total of 16 male rats were used, half of them were sexually experienced while the other half were sexually inexperienced. After three sessions of sexual interaction to ejaculation, the sexually-experienced males presented shorter mount, intromission, and ejaculation latencies. Those rats presented a higher total dendritic density in the mPFC, and a higher numerical density of thin, mushroom, stubby, and wide spines. Sexual experience also increased the numerical density of mushroom spines in the NAcc. In both the mPFC and NAcc of the sexually experienced rats, there was a lower proportional density of thin spines and a higher proportional density of mushroom spines. Results show that the improvement in copulatory efficiency resulting from prior sexual experience in male rats is associated with changes in the proportional density of thin and mushroom dendritic spines in the mPFC and NAcc. This could represent the consolidation of afferent synaptic information in these brain regions, derived from the stimulus-sexual reward association.
Assuntos
Agaricales , Núcleo Accumbens , Ratos , Masculino , Animais , Comportamento Sexual Animal , Copulação , Córtex Pré-Frontal , Espinhas DendríticasRESUMO
INTRODUCTION: Parkinson's disease represents a neurodegenerative condition characterized by the progressive loss of dopaminergic neurons within the Substantia Nigra pars compacta (SNpc), resulting in diminished dopamine levels in the striatum (STR) and chronic neuroinflammation. Recent investigations have proposed the neuroprotective potential of the endocannabinoid system in neurodegenerative disorders. ß-caryophyllene (BCP) is recognized for its antioxidant and anti-inflammatory properties, attributed to its activation of the type 2 cannabinoid receptor. This study aimed to assess the neuroprotective impact of BCP on dopaminergic neurons, with a particular focus on inhibiting the NLRP3 inflammasome. METHODS: A model of hemiparkinsonism, induced by 6-hydroxydopamine (6-OHDA), served as the experimental framework. Motor function was evaluated using the cylinder test, and inflammasome inhibition was determined by assessing the expression of NLRP3, caspase-1, and the pro-inflammatory cytokine IL-1ß in both the SNpc and STR through ELISA analysis. Furthermore, the evaluation of oxidative stress was facilitated by quantifying malondialdehyde (MDA) levels in the same regions. RESULTS: BCP treatment demonstrated significant improvements in motor dysfunction, as assessed by the cylinder test (p=0.0011) and exhibited a neuroprotective effect on dopaminergic neurons within the SNpc (p=0.0017), as well as nerve fibers in the STR (p=0.0399). In terms of its ability to inhibit the inflammasome, BCP led to decreased expression levels of NLRP3 (p=0.0401 in STR and p = 0.0139 in SNpc), caspase-1 (p=0.0004 in STR), and MDA (p=0.0085 in STR and p=0.0414 in SNpc). CONCLUSION: These results point to BCP's potential in mitigating the motor deficit, inhibiting NLRP3 inflammasome activation, and attenuating lipid peroxidation induced by 6-OHDA.
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Doenças Neuroinflamatórias , Fármacos Neuroprotetores , Humanos , Caspases/metabolismo , Caspases/farmacologia , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo , Inflamassomos/metabolismo , Camundongos Endogâmicos C57BL , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/metabolismo , Neuroproteção , Fármacos Neuroprotetores/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR , Oxidopamina , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Camundongos , AnimaisRESUMO
It has recently been shown that the administration of probiotics can modulate the microbiota-gut-brain axis and may have favorable effects in models of Parkinson's disease. In this study, we used a hemiparkinsonism model induced by the neurotoxin 6-OHDA to evaluate the efficacy of the administration of a four-week administration of a mixture containing the microorganisms Lactobacillus fermentum LH01, Lactobacillus reuteri LH03, and Lactobacillus plantarum LH05. The hemiparkinsonism model induced an increase in rotations in the apomorphine test, along with a decrease in the latency time to fall in the rotarod test on days 14 and 21 after surgery, respectively. The administration of probiotics was sufficient to improve this condition. The model also showed a decrease in tyrosine hydroxylase immunoreactivity in the striatum and the number of labeled cells in the substantia nigra, both of which were counteracted by the administration of probiotics. The permeability of the blood-brain barrier was increased in the model, but this effect was reversed by the probiotics for both brain regions. The gut barrier was permeated with the model, and this effect was reversed and dropped to lower levels than the control group after the administration of probiotics. Finally, lipid peroxidation showed a pattern of differences similar to that of permeabilities. The inhibition of the permeability of the blood-brain and gut barriers mediated by the administration of probiotics will likely provide protection by downregulating oxidative stress, thus affecting the rotarod test performance.
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Lactobacillus , Transtornos Parkinsonianos , Humanos , Barreira Hematoencefálica , Administração Oral , PermeabilidadeRESUMO
Lesions to the corticospinal tract result in several neurological symptoms and several rehabilitation protocols have proven useful in attempts to direct underlying plastic phenomena. However, the effects that such protocols may exert on the dendritic spines of motoneurons to enhance accuracy during rehabilitation are unknown. Thirty three female Sprague-Dawley adult rats were injected stereotaxically at the primary motor cerebral cortex (Fr1) with saline (CTL), or kainic acid (INJ), or kainic acid and further rehabilitation on a treadmill 16 days after lesion (INJ+RB). Motor performance was evaluated with the the Basso, Beatie and Bresnahan (BBB) locomotion scale and in the Rotarod. Spine density was quantified in a primary dendrite of motoneurons in Lamina IX in the ventral horn of the thoracolumbar spinal cord as well as spine morphology. AMPA, BDNF, PSD-95 and synaptophysin expression was evaluated by Western blot. INJ+RB group showed higher scores in motor performance. Animals from the INJ+RB group showed more thin, mushroom, stubby and wide spines than the CTL group, while the content of AMPA, BDNF, PSD-95 and Synaptophysin was not different between the groups INJ+RB and CTL. AMPA and synaptophysin content was greater in INJ group than in CTL and INJ+RB groups. The increase in the proportion of each type of spine observed in INJ+RB group suggest spinogenesis and a greater capability to integrate the afferent information to motoneurons under relatively stable molecular conditions at the synaptic level.
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Córtex Motor , Animais , Feminino , Ratos , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Espinhas Dendríticas/fisiologia , Ácido Caínico , Córtex Motor/metabolismo , Neurônios Motores/metabolismo , Ratos Sprague-DawleyRESUMO
Early life stress induced by maternal separation (MS) causes neuroendocrine, behavioral, and metabolic alterations that are related to gut dysbiosis. MS also increases microglial activation and decreases neurogenesis. Whether these long-term alterations are maintained or worsened in the absence of gut microbiota remains unknown. Hence, this study evaluated the effect of MS symptomatology after antibiotic-induced microbiota depletion (AIMD) in adult rats. Control and maternally separated (3 h per day from postnatal day one to 14, MS180) rats were subjected to AIMD for one month, then assessed for behavioral, metabolic, and neuroendocrine responses. Effects of MS180 and AIMD on gut microbiota were confirmed by qPCR. The data indicate that MS180 caused a passive coping strategy in the forced swimming test and decreased hippocampal neurogenesis. In addition, fasting glucose, cholesterol, and corticosterone levels increased, which correlated with a decrease in Lactobacillus spp counts in the caecum. AIMD also increased immobility in the forced swimming test, decreased hippocampal neurogenesis, and augmented corticosterone levels. However, it had no effects on glucose homeostasis or plasma lipid levels. Furthermore, the MS180-induced long-term effects on behavior and neurogenesis were not affected by microbiota depletion. Meanwhile, the metabolic imbalance was partially reversed in MS180 + AIMD rats. These results show that AIMD mimics the behavioral consequences of MS180 but may prevent metabolic imbalance, suggesting that gut dysbiosis could be part of the mechanisms involved in the maintenance of the long-term consequences of early life stress.
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Microbiota , Estresse Psicológico , Animais , Ratos , Antibacterianos/farmacologia , Comportamento Animal/fisiologia , Corticosterona , Disbiose , Glucose/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Privação Materna , Sistema Hipófise-Suprarrenal/metabolismoRESUMO
The lesions induced by Ibotenic acid (IA) emulate some of the symptoms associated with schizophrenia, such as impaired working memory that is predominantly organized by the medial prefrontal cortex (mPFC), or difficulties in social interactions that aremainly organized by the amygdala (AMG). The plastic capacity of dendritic spines in neurons of the mPFC and AMG is modulated by molecules that participate in the known deterioration of working memory, although the influence of these on the socialization of schizophrenic patients is unknown. Here, the effect of a neonatal IA induced lesion on social behavior and working memory was evaluated in adult rats, along with the changes in cytoarchitecture of dendritic spines and their protein content, specifically the postsynaptic density protein 95 (PSD-95), Synaptophysin (Syn), AMPA receptors, and brain-derived neurotrophic factor (BDNF). Both working memory and social behavior were impaired, and the density of the spines, as well as their PSD-95, Syn, AMPA receptor and BDNF content was lower in IA lesioned animals. The proportional density of thin, mushroom, stubby and wide spines resulted in plastic changes that suggest the activation of compensatory processes in the face of the adverse effects of the lesion. In addition, the reduction in the levels of the modulating factors also suggests that the signaling pathways in which such factors are implicated would be altered in the brains of patients with schizophrenia. Accordingly, the experimental study of such signaling pathways is likely to aid the development of more effective pharmacological strategies for the treatment of schizophrenia.
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Tonsila do Cerebelo/patologia , Comportamento Animal , Espinhas Dendríticas/patologia , Plasticidade Neuronal , Córtex Pré-Frontal/patologia , Esquizofrenia/patologia , Psicologia do Esquizofrênico , Tonsila do Cerebelo/metabolismo , Tonsila do Cerebelo/fisiopatologia , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Espinhas Dendríticas/metabolismo , Modelos Animais de Doenças , Proteína 4 Homóloga a Disks-Large/metabolismo , Ácido Ibotênico , Masculino , Aprendizagem em Labirinto , Memória de Curto Prazo , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/fisiopatologia , Ratos Sprague-Dawley , Receptores de AMPA/metabolismo , Esquizofrenia/induzido quimicamente , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatologia , Comportamento Social , Sinaptofisina/metabolismoRESUMO
Landfill leachate is a complex mixture of organic and inorganic molecules, as well as environmental pollutants that can cause harm to ecosystems and living beings. The micronucleus test in peripheral blood erythrocytes was used to evaluate the genotoxic and cytotoxic effects of exposure to a landfill leachate from an outdoor solid waste storage system on Wistar strain rats at different developmental stages, pre-adolescents and young adults, and the heavy metal content of the leachate was determined by atomic absorption spectrometry. Contents of arsenic, cadmium, chromium, mercury, and lead in the landfill leachate were outside the allowable international standards, and the exposure to the landfill leachate caused genotoxic and cytotoxic effects on Wistar rats, where the pre-adolescent animals were more susceptible to the toxics contained in the landfill leachate than young adults. Heavy metals contained in landfill leachate, individually or synergically with other molecules can be responsible for clastogenic and cytotoxic effects that can be harmful to humans and ecosystems.
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Eliminação de Resíduos , Poluentes Químicos da Água , Animais , Dano ao DNA , Ecossistema , Ratos , Ratos Wistar , Resíduos Sólidos/análise , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidadeRESUMO
Epilepsy is a chronic neurobehavioral disorder whereby an imbalance between neurochemical excitation and inhibition at the synaptic level provokes seizures. Various experimental models have been used to study epilepsy, including that based on acute or chronic administration of Pentylenetetrazol (PTZ). In this study, a single PTZ dose (60 mg/kg) was administered to adult male rats and 30 min later, various neurobiological parameters were studied related to the transmission and modulation of excitatory impulses in pyramidal neurons of the hippocampal CA1 field. Rats experienced generalized seizures 1-3 min after PTZ administration, accompanied by elevated levels of Synaptophysin and Glutaminase. This response suggests presynaptic glutamate release is exacerbated to toxic levels, which eventually provokes neuronal death as witnessed by the higher levels of Caspase-3, TUNEL and GFAP. Similarly, the increase in PSD-95 suggests that viable dendritic spines are functional. Indeed, the increase in stubby and wide spines is likely related to de novo spinogenesis, and the regulation of neuronal excitability, which could represent a plastic response to the synaptic over-excitation. Furthermore, the increase in mushroom spines could be associated with the storage of cognitive information and the potentiation of thin spines until they are transformed into mushroom spines. However, the reduction in BDNF suggests that the activity of these spines would be down-regulated, may in part be responsible for the cognitive decline related to hippocampal function in patients with epilepsy.
Assuntos
Fator Neurotrófico Derivado do Encéfalo/efeitos dos fármacos , Região CA1 Hipocampal/efeitos dos fármacos , Espinhas Dendríticas/efeitos dos fármacos , Epilepsia/induzido quimicamente , Epilepsia/metabolismo , Antagonistas GABAérgicos/farmacologia , Plasticidade Neuronal/efeitos dos fármacos , Pentilenotetrazol/farmacologia , Células Piramidais/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Antagonistas GABAérgicos/administração & dosagem , Masculino , Pentilenotetrazol/administração & dosagem , Ratos , Ratos Sprague-DawleyRESUMO
Aging is associated with detrimental cellular and cognitive changes, making it an important public health concern; yet, many of these changes may be influenced by nutritional interventions. The natural sesquiterpene ß-caryophyllene (BCP) has anti-inflammatory and antioxidant effects that are mediated by cannabinoid type-2 receptor activation, and these actions promote neuroprotection in different animal models that involve a cognitive damage. Consequently, whether chronic administration of BCP might prevent the age-related cellular and cognitive damage in a model of aging induced by chronic d-galactose (GAL) consumption was assessed here. Male BALB/c mice were administered BCP (10 mg/kg, oral), GAL (300 mg/kg, intraperitoneal), or GAL+BCP, and long-term memory and cognitive flexibility were evaluated in the normal and the reverse phases of Morris water maze test. In addition, immunohistochemistry was performed on prefrontal and hippocampal brain slices to detect glial acidic fibrillary protein and DNA oxidation. Although GAL administration reduced cognitive flexibility (P = .0308), this functional damage was not reversed by administering BCP. However, GAL administration also elevated the total number of astrocytes and their interactions in the hippocampus, and increasing DNA oxidation in the prefrontal cortex. BCP administration impeded the rise in the total number of astrocytes (P = .0286) and the DNA oxidation (P = .0286) in mice that received GAL. Hence, although BCP did not improve cognitive flexibility, it did produce a neuroprotective effect at the molecular and cellular level in the GAL model of aging.