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1.
Nutr Cancer ; 74(8): 3035-3050, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35129016

RESUMO

Cancer patients, including breast cancer patients, live in a hypercoagulable state. Chemo- and hormone- therapy used in the treatment of breast cancer increases the risk of thrombosis. Due to differences in health care services between developed and developing countries, the survival rate of women with breast cancer in developing countries is low. Consequently, ethnomedicines are used and their efficacy as potential alternatives are being scientifically explored. The seed oils of Kigelia africana, Ximenia caffra and Mimusops zeyheri have anti-proliferative effects on hormone-dependent (MCF-7) and cytotoxic effects on hormone-independent (MDA-MB-231) breast cancer cells. In this study, we determined if these seed oils reduce the thrombogenic ability of breast cancer cells by measuring the platelet surface expression of the activation-specific antigens CD62P and CD63. MDA-MB-231 and MCF-7 cells were pretreated with the seed oils before being exposed to whole blood of human female volunteers. An increase in CD62P and CD63 expression following whole blood exposure to untreated breast cancer cells was observed. Treated MDA-MB-231 cells reduced CD62P and CD63 expression while treated MCF-7 cells increased CD62P and decreased CD63 expression. Kigelia africana, Ximenia caffra and Mimusops zeyheri seed oils are able to reduce the thrombogenic ability of MDA-MB-231 breast cancer cells.


Assuntos
Neoplasias da Mama , Mimusops , Olacaceae , Óleos de Plantas , Antígenos CD/metabolismo , Biomarcadores , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Feminino , Hormônios , Humanos , Mimusops/química , Olacaceae/química , Selectina-P/metabolismo , Óleos de Plantas/farmacologia , Ativação Plaquetária , Sementes/química , Tetraspanina 30/metabolismo
2.
Oxid Med Cell Longev ; 2020: 1941480, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32273939

RESUMO

Nonmotor symptoms (NMS) such as anxiety, depression, and cognitive deficits are frequently observed in Parkinson's disease (PD) and precede the onset of motor symptoms by years. We have recently explored the short-term effects of Fluvoxamine, a selective serotonin reuptake inhibitor (SSRI) on dopaminergic neurons in a parkinsonian rat model. Here, we report the long-term effects of Fluvoxamine, on early-life stress-induced changes in the brain and behavior. We specifically evaluated the effects of Fluvoxamine on brain mechanisms that contribute to NMS associated with PD in a unilateral 6-hydroxydopamine-lesioned rat model. A 14-day early postnatal maternal separation protocol was applied to model early-life stress followed by unilateral intracerebral infusion of 6-hydroxydopamine (6-OHDA) to model aspects of parkinsonism in rats. The anxiolytic, antidepressant, and cognitive effects of Fluvoxamine were confirmed using the elevated plus-maze (EPM) test, sucrose preference test (SPT), and Morris water maze (MWM) test. Further to that, our results showed that animals exposed to early-life stress displayed increased plasma corticosterone and malondialdehyde (MDA) levels which were attenuated by Fluvoxamine treatment. A 6-OHDA lesion effect was evidenced by impairment in the limb-use asymmetry test as well as decreased dopamine (DA) and serotonin levels in the striatum, prefrontal cortex, and hippocampus. These effects were surprisingly attenuated by Fluvoxamine treatment in all treated rats. This study is the first to suggest that early and long-term treatment of neuropsychological diseases with Fluvoxamine may decrease the vulnerability of dopaminergic neurons that degenerate in the course of PD.


Assuntos
Fluvoxamina/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Estresse Psicológico/tratamento farmacológico , Animais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley , Inibidores Seletivos de Recaptação de Serotonina/farmacologia
3.
Oxid Med Cell Longev ; 2020: 5756382, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32148652

RESUMO

Alzheimer's disease is a complex debilitating neurodegenerative disease for which there is no cure. The lack of reliable biomarkers for Alzheimer's disease has made the evaluation of the efficacy of new treatments difficult and reliant on only clinical symptoms. In an aged population where cognitive function may be deteriorating for other reasons, the dependence on clinical symptoms is also unreliable. However, it is well established that infusion of ß-amyloid into the dorsal hippocampus of rats leads to cognitive impairment in a rat model of Alzheimer's disease. Moreover, the blood plasma of ß-amyloid-lesioned rats exhibits a distinct variation of the dielectric constant and conductivity when compared to that of normal rats in a time-dependent manner. These two electric parameters of blood plasma may therefore act as potential biomarkers for dementia due to Alzheimer's disease. This review is aimed at highlighting evidences that support blood plasma electrical properties, e.g., dielectric constant and conductivity as possible novel biomarkers for the early development and progression of dementia due to Alzheimer's disease.


Assuntos
Doença de Alzheimer/sangue , Biomarcadores/sangue , Plasma/química , Feminino , Humanos , Masculino
4.
Neuroreport ; 30(17): 1157-1165, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31568187

RESUMO

Here, we explored the hypothesis that parental cocaine exposure could alter epigenetic machinery in their drug-naive offspring while early postnatal fostering may further modify the accompanied neurochemical and functional components. Variant drug-naive pups were produced from cocaine-exposed or unexposed C57BL/6 female mice that were matched with their male counterparts for mating. Within 3 days of birth, half of the pups were cross-fostered and nurtured by non-biological lactating dams. The pups were initially examined for locomotor activity and memory performance and subsequently for changes in DNA methylation in promoter regions of cAMP response element modulator (Crem) and Fosb in the prefrontal cortex at 48 days postnatum. The impact of postnatal fostering on these parameters was also investigated. Our results showed that cocaine exposure significantly decreased both Crem and Fosb methylation in the prefrontal cortex of progenitor mice, while similar patterns of methylation were replicated in the brains of drug-naive non-fostered offspring mice but reversed by postnatal fostering. Furthermore, offspring raised by cocaine-exposed dams were impaired in discriminative learning and exhibited memory decline, whereas locomotor activity remains unaltered in all groups of mice. Our data provide some evidence that indirect exposure to cocaine may cause marked epigenetic changes within the cortical networks of drug-naive descendants and that mediation by Crem/Fosb signalling in this brain region may be beneficial, while early postnatal fostering may further engineer molecular switching that may predispose the individual to future risky behaviours as well as accumulative potential to developing cognitive impairment later in life.


Assuntos
Cocaína/toxicidade , Metilação de DNA/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Animais , Comportamento Animal/efeitos dos fármacos , Transtornos Relacionados ao Uso de Cocaína , Modulador de Elemento de Resposta do AMP Cíclico/genética , Feminino , Masculino , Camundongos Endogâmicos C57BL , Córtex Pré-Frontal/efeitos dos fármacos , Gravidez , Proteínas Proto-Oncogênicas c-fos/genética
5.
J Chem Neuroanat ; 94: 86-92, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30336207

RESUMO

The use of combination antiretroviral therapy (cART) has been successful in suppressing HIV-1 replication and restoring peripheral immune functioning in HIV-infected individuals. Despite these advances in the management of HIV, neurocognitive impairments continue to be diagnosed in HIV-infected patients on treatment, even when the viral load is low. Of interest is the observation that deficiencies in brain function in these individuals are marked by a persistent presence of neuroinflammation. Therefore, in this study we investigated whether long-term exposure to ART could contribute to neuroinflammation. Mice were subsequently administered a daily single dose of either Tenofovir disoproxil fumarate or Nevirapine orally for 8 weeks. After treatment, hippocampal tissue was collected from the brains of drug-treated and control mice and the levels of interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α) and brain-derived neurotrophic factor (BDNF) determined. Our results showed that administration of Tenofovir disoproxil fumarate and Nevirapine induced astrogliosis and up-regulated IL-1ß and TNF-α. In addition, we found that Nevirapine reduced the expression of BDNF. Together these results suggest that Nevirapine promotes inflammatory and reduces neuroprotective processes in the hippocampus of mice. Our findings therefore highlight the potential of ART to be harmful to the brain and as such these drugs may contribute to the development of HIV-associated neurocognitive disorder (HAND).


Assuntos
Antirretrovirais/administração & dosagem , Encefalite/induzido quimicamente , Hipocampo/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Nevirapina/administração & dosagem , Tenofovir/administração & dosagem , Animais , Antirretrovirais/efeitos adversos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Encefalite/metabolismo , Encefalite/patologia , Hipocampo/metabolismo , Hipocampo/patologia , Interleucina-1beta/metabolismo , Camundongos , Nevirapina/efeitos adversos , Tenofovir/efeitos adversos , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima/efeitos dos fármacos
6.
Metab Brain Dis ; 33(5): 1743-1753, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29987524

RESUMO

Human immunodeficiency virus type 1 (HIV-1) affects the central nervous system (CNS) that may lead to the development of HIV-associated neuropathologies. Tat protein is one of the viral proteins that have been linked to the neurotoxic effects of HIV. Since many individuals living with HIV often experience significant adverse circumstances, the present study investigated whether exposure to stressful conditions would exacerbate harmful effects of tat protein on brain function. Tat protein (10 µg/10 µl) was injected bilaterally into the dorsal hippocampus of the animal using stereotaxic techniques. The control group received an injection of saline (10 µl). Some control and tat protein-treated animals were subjected to restrain stress for 6 h per day for 28 days and compared to a non-stress group. All animals underwent two behavioural tests, the open field test (OFT) and the novel object recognition test (NORT) to assess their mood state and cognitive function respectively. The release of pro-inflammatory cytokines (TNF-α and IL-1ß) and the expression of mineralocorticoid (MR) and glucocorticoid (GR) receptors were also measured to see whether the impact of the repetitive stress on Tat protein-induced behavioural effects was mediated by elements of the immune system and the HPA axis. Rats treated with tat protein showed the following behavioural changes when compared to control animals: there was a significant decrease in time spent in the center of the open field during the OFT, a significant reduction in time spent with the novel object during the NORT, but no change in locomotor activity. Real-time PCR data showed that the expression levels of GR and MR mRNA were significantly reduced, while Western blot analysis showed that the protein expression levels of TNF-α and IL-1ß were significantly increased. The present findings indicated that injection of tat protein into the hippocampus of rats not subjected to stress may lead to anxiety-like behaviour and deficits in learning and memory. Tat-treated animals subjected to stress evoked only a modest effect on their behaviour and neurochemistry, while stress alone led to behavioural and neurochemical changes similar to tat protein.


Assuntos
Produtos do Gene tat/farmacologia , HIV , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Interleucina-1beta/metabolismo , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Virais/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Produtos do Gene tat/administração & dosagem , Masculino , Memória/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Restrição Física/fisiologia , Restrição Física/psicologia , Técnicas Estereotáxicas , Estresse Psicológico/metabolismo , Proteínas Virais/administração & dosagem
7.
Behav Brain Res ; 353: 203-209, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30029998

RESUMO

Human immunodeficiency virus type 1 (HIV) has infected more than 40 million people worldwide and is associated with central nervous system (CNS) disruption in at least 30% of these persons. The use of highly active antiretroviral therapy (HAART) has significantly reduced the systemic immunopathology associated with HIV, but the occurrence of neurological disorders continues to be reported in notable numbers. The present study evaluated the potential of rosmarinic acid to reverse the detrimental effects of an intracerebral injection of the viral protein tat. Control and tat-injected rats were also subjected to repetitive restrain stress (RRS) for 28 days, 6 h per day, to investigate whether subsequent stress exposure would worsen the effects of tat. 14 days after the initiation of RRS, animals were treated with rosmarinic acid (10 mg/kg given intraperitoneally) daily until the end of the stress exposure period. We assessed locomotor activity and anxiety-like behavioral changes. We also measured plasma corticosterone levels and quantified the expression of mineralocorticoid receptors (MR), glucocorticoid receptors (GR) and brain-derived neurotrophic factor (BDNF) in the hippocampus. Rosmarinic acid attenuated anxiety-like behavior induced by tat and stress, reduced plasma corticosterone levels and increased the expression of hippocampal GR, MR and BDNF when compared to controls. These results suggest that rosmarinic acid may reverse the anxiogenic effect of HIV-1 viral protein tat and related stress through modulation of the hypothalamic-pituitary-adrenal axis and hippocampal neurotrophic factor levels.


Assuntos
Ansiolíticos/farmacologia , Ansiedade/tratamento farmacológico , Cinamatos/farmacologia , Depsídeos/farmacologia , Produtos do Gene tat/toxicidade , Fármacos Neuroprotetores/farmacologia , Estresse Psicológico/tratamento farmacológico , Animais , Ansiedade/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Corticosterona/sangue , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Atividade Motora/efeitos dos fármacos , Distribuição Aleatória , Ratos Sprague-Dawley , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/metabolismo , Estresse Psicológico/metabolismo , Ácido Rosmarínico
8.
Metab Brain Dis ; 33(2): 411-420, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28963688

RESUMO

Alterations in gene expression within the neural networks of prefrontal cortex (PFC) and hippocampus (HPC) are known to contribute to behavioural phenotypes associated with drug intake. However, the functional consequences of regulated expression patterns of Fosb and Crem (cAMP response element modulator) in both brain regions in response to volitional intake of cocaine in social environment is yet to be explored. Here, we first exposed young adult mice to cocaine (300 mg/L) and water concurrently for 30 days in the IntelliCage to investigate consumption preference, and subsequently for 28 days during which persistent motivated drug seeking behaviours were examined. Thereafter, locomotor activity and memory performance of the mice were assessed. DNA methylation status in the promoters of Fosb and Crem genes were also evaluated. We show that mice that had extended access to cocaine exhibited motivational deficit and demonstrated decreased locomotor activity and intact recognition memory. These changes were accompanied by hypomethylation or hypermethylation in the promoters of Fosb and Crem genes in the PFC and HPC of the cocaine-experienced mice, respectively. Together, these findings correlate the molecular changes to behavioural effects of the treatment and further suggests a possible activation of prefrontal cortical networks by social interaction episodes in the IntelliCage which possibly enhanced behavioural control that dampens mice sensitivity to cocaine rewards. Furthermore, our data delineate the molecular response of Crem and Fosb to oral cocaine in group-housed mice and demonstrates differential regulation of activities within the substrate brain regions studied.


Assuntos
Comportamento Animal/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Animais , Cocaína , Feminino , Hipocampo/metabolismo , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Recompensa
9.
Metab Brain Dis ; 33(2): 387-396, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28993949

RESUMO

Alzheimer's disease (AD) is characterized by extracellular deposition of amyloid-ß (Aß) plaques. These protein deposits impair synaptic plasticity thereby producing a progressive decline in cognitive function. Current therapies are merely palliative and only slow cognitive decline. Poly-N-methylated Aß-Peptide C-Terminal Fragments (MEPTIDES) were recently shown to reduce Aß toxicity in vitro and in Drosophila melanogaster, however whether these novel compounds are effective in inhibiting Aß-induced toxicity in the mammalian brain remains unclear. We therefore investigated whether MEPTIDES have the ability to reduce the neurotoxic effects of Aß in male Sprague-Dawley (SD) rats. Aß42 (100 µg, 2 mM) or vehicle (0.15 M Tris buffer) was stereotaxically injected bilaterally into the dorsal hippocampus at a rate of 1 µl/min for 10 min. The effects on hippocampal-mediated learning were subsequently assessed using the Morris water maze (MWM). The presence of apoptotic activity was also assessed by determining the expression levels of active caspase-3 using real-time polymerase chain reaction and Western Blot techniques. In addition, half of the animals (n = 20) received an intraperitoneal (i.p.) injection of MEPTIDES (2 mg/kg) 48 h after intrahippocampal injection of Aß42. Matrix-assisted laser desorption/ionization-time-of-flight (MALDI -TOF) mass spectrometry (MS) showed that MEPTIDES crossed the blood brain barrier (BBB) and revealed their distribution in the rat brain. Rats treated with Aß42 displayed spatial learning deficits and increased hippocampal caspase-3 gene (CASP-3) expression which was reversed by subsequent injection of MEPTIDES. The present results show that MEPTIDES have the potential to reverse the toxic effects of Aß42 in vivo.


Assuntos
Peptídeos beta-Amiloides/farmacologia , Encéfalo/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Peptídeos/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Encéfalo/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/metabolismo , Modelos Animais de Doenças , Masculino , Transtornos da Memória/metabolismo , Ratos Sprague-Dawley
10.
Prog Brain Res ; 235: 65-91, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29054292

RESUMO

Over the years, drug addiction has proven to be a perplexing conundrum for scientists. In attempts to decipher the components of the puzzle, multiple theories of addiction have been proposed. While these theories have assisted in providing essential fundamental information, current research recommends that a new theory needs to be presented taking into consideration the results of recent developments in the fields of neuroimmunology, genetics, and neuropsychiatry. After extensively examining the published literature, we propose in this review that neuroinflammation and hypothalamic functioning strongly underpin addictive behavior. To substantiate this notion, we typed the search-string "cocaine addiction, hypothalamus, and inflammation" into PubMed and Google Scholar. 50 and 1280 results were obtained in PubMed and Google Scholar, respectively. All article abstracts were perused for relevance to this review and 177 articles were used. Recent studies have purported that both acute and chronic psychostimulant use can activate specific components of the innate immune system. Findings such as these provide the scientific evidence supporting a hypothesis that includes a role for the innate immune system and inflammation in addictive behavior. However, the pathophysiological mechanisms by which they mediate the development of addiction have not been clearly delineated. The following review particularly focuses on the lateral hypothalamus and its functioning in satiety, and how inflammatory processes in the brain may contribute to addiction.


Assuntos
Comportamento Aditivo/fisiopatologia , Inflamação/fisiopatologia , Saciação/fisiologia , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia , Animais , Humanos
11.
Int J Dev Neurosci ; 60: 63-69, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28465238

RESUMO

Exposure to repetitive stress has a negative influence on cognitive-affective functioning, with growing evidence that these effects may be mediated by a dysregulated hypothalamic-pituitary-adrenal (HPA) axis, abnormal neurotrophic factor levels and its subsequent impact on hippocampal function. However, there are few data about the effect of repetitive stressors on epigenetic changes in the hippocampus. In the present study, we examine how repetitive restrain stress (RRS) affects cognitive-affective functioning, HPA axis regulation, brain-derived neurotrophic factor (BDNF) levels, and global hippocampal DNA methylation. RRS was induced in rats by restraining the animals for 6h per day for 28 days. The novel object recognition test (NORT) was used to assess cognitive functioning and the open field test (OFT) was performed to assess anxiety-like behavior during the last week of stress. Hippocampal BDNF levels, glucocorticoid (GR) and mineralocorticoid (MR) receptor mRNA were assessed using real-time PCR and confirmed with Western blot, while ELISAs were used to determine plasma corticosterone levels and the global methylation status of the hippocampus. Animals exposed to repetitive stress demonstrated significant alterations in the NORT and OFT, had significantly increased plasma corticosterone and significantly decreased hippocampal BDNF concentrations. The expression levels of GR and MR mRNA and protein levels of these genes were significantly decreased in the stressed group compared to control animals. The global DNA methylation of the hippocampal genome of stressed animals was also significantly decreased compared to controls. The data here are consistent with previous work emphasizing the role of the HPA axis and neurotrophic factors in mediating cognitive-affective changes after exposure to repetitive stressors. Our findings, however, extend the literature by indicating that epigenetic alterations in the hippocampal genome may also play an important role in the development of hippocampus-associated behavioral abnormalities.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Transtornos Cognitivos/fisiopatologia , Hipocampo/fisiopatologia , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Estresse Psicológico/fisiopatologia , Animais , Transtornos Cognitivos/etiologia , Metilação de DNA , Regulação para Baixo , Masculino , Ratos , Ratos Sprague-Dawley , Recidiva , Estresse Psicológico/complicações
12.
Cell Mol Life Sci ; 74(15): 2735-2747, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28255755

RESUMO

The detrimental effects of drug abuse are apparently not limited to individuals but may also impact the vulnerability of their progenies to develop addictive behaviours. Epigenetic signatures, early life experience and environmental factors, converge to influence gene expression patterns in addiction phenotypes and consequently may serve as mediators of behavioural trait transmission between generations. The majority of studies investigating the role of epigenetics in addiction do not consider the influence of social interactions. This shortcoming in current experimental approaches necessitates developing social models that reflect the addictive behaviour in a free-living social environment. Furthermore, this review also reports on the advancement of interventions for drug addiction and takes into account the emerging roles of histone deacetylase (HDAC) inhibitors in the etiology of drug addiction and that HDAC may be a potential therapeutic target at nucleosomal level to improve treatment outcomes.


Assuntos
Alcoolismo/genética , Epigênese Genética , Meio Social , Transtornos Relacionados ao Uso de Substâncias/genética , Alcoolismo/tratamento farmacológico , Alcoolismo/metabolismo , Animais , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Modelos Animais de Doenças , Descoberta de Drogas , Epigênese Genética/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Histona Desacetilases/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/genética , Estresse Psicológico/metabolismo , Transtornos Relacionados ao Uso de Substâncias/tratamento farmacológico , Transtornos Relacionados ao Uso de Substâncias/metabolismo
13.
Behav Brain Funct ; 11: 3, 2015 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-25880773

RESUMO

BACKGROUND: HIV-1 is a global catastrophe, and is exceedingly prevalent in Sub-Saharan Africa. HIV-associated neurocognitive disorder is characterized by symptoms such as motor impairments, a decline in cognition, and behavioural irregularities. The aim of this study was to provide insight into the fundamental behavioural and histopathological mechanisms underlying the development and progression of HIV-1 neuropathology. METHODS: Using stereotaxic techniques, Tat protein Clade B (1 µg/µl, 10 µl) was injected bilaterally into the dorsal hippocampus of male Sprague-Dawley rats. The Morris water maze (MWM) and novel object recognition test (NORT) were used to assess spatial learning and recognition memory, respectively. Haematoxylin and eosin staining was used to identify the histopathological changes. RESULTS: A highly significant increase in latency to reach the hidden platform in the MWM implied that noteworthy hippocampal damage had occurred. Severe behavioural deficits were also observed in the NORT where the Tat-injected group showed a greater preference for a familiar object over a novel one. This damage was confirmed by the histopathological changes (increased astrogliosis, cells becoming eosinophilic and a significant reduction in the pyramidal cell layer) observed in the hippocampus. Additionally, increases in the hippocampal mass and protein were observed, consistent with the structural alterations. CONCLUSION: This study highlights the relationship between hippocampal-associated behavioural changes and histologic alterations following stereotaxic intra-hippocampal administration of Tat protein in rats. The implications of this study may positively impact the fields of immunology and neuroscience by encouraging future researchers to consider novel strategies to understand the complexities of the pathogenesis of HIV-associated neurocognitive disorder.


Assuntos
Comportamento Animal/efeitos dos fármacos , HIV-1 , Hipocampo/patologia , Produtos do Gene tat do Vírus da Imunodeficiência Humana/toxicidade , Animais , Astrócitos/patologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Injeções , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/psicologia , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/química , Células Piramidais/patologia , Ratos , Ratos Sprague-Dawley , Reconhecimento Psicológico/efeitos dos fármacos , Percepção Espacial/efeitos dos fármacos , Técnicas Estereotáxicas
14.
Metab Brain Dis ; 29(2): 255-60, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24399497

RESUMO

In response to acute adversity, emotional signals shift the body into a state that permits rapid detection, identification, and appropriate response to a potential threat. The stress response involves the release of a variety of substances, including neurotransmitters, neurotrophic factors, hormones, and cytokines, that enable the body to deal with the challenges of daily life. The subsequent activation of various physiological systems can be both protective and damaging to the individual, depending on timing, intensity, and duration of the stressor. Successful recovery from stressful challenges during early life leads to strengthening of synaptic connections in health-promoting neural networks and reduced vulnerability to subsequent stressors that can be protective in later life. In contrast, chronic intense uncontrollable stress can be pathogenic and lead to disorders such as depression, anxiety, hypertension, Alzheimer's disease, Parkinson's disease, and an increased toxic response to additional stressors such as traumatic brain injury and stroke. This review briefly explores the interaction between stress experienced at different stages of development and exercise later in life.


Assuntos
Encéfalo/fisiologia , Exercício Físico/fisiologia , Rede Nervosa/fisiologia , Estresse Psicológico/metabolismo , Animais , Humanos , Estresse Psicológico/psicologia
15.
Metab Brain Dis ; 24(4): 525-39, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19844780

RESUMO

Prenatal stress has been associated with increased vulnerability to psychiatric disturbances including schizophrenia, depression, attention-deficit hyperactivity disorder and autism. Elevated maternal circulating stress hormones alter development of neural circuits in the fetal brain and cause long-term changes in behaviour. The aim of the present study was to investigate whether mild prenatal stress increases the vulnerability of dopamine neurons in adulthood. A low dose of 6-hydroxydopamine (6-OHDA, 5 microg/4 microl saline) was unilaterally infused into the medial forebrain bundle of nerve fibres in the rat brain in order to create a partial lesion of dopamine neurons which was sufficient to cause subtle behavioural deficits associated with early onset of Parkinson's disease without complete destruction of dopamine neurons. Voluntary exercise appeared to have a neuroprotective effect resulting in an improvement in motor control and decreased asymmetry in the use of left and right forelimbs to explore a novel environment as well as decreased asymmetry of tyrosine hydroxylase-positive cells in the substantia nigra pars compacta and decreased dopamine cell loss in 6-OHDA-lesioned rats. Prenatal stress appeared to enhance the toxic effect of 6-OHDA possibly by reducing the compensatory adaptations to exercise.


Assuntos
Terapia por Exercício/métodos , Doença de Parkinson/prevenção & controle , Doença de Parkinson/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Estresse Fisiológico/fisiologia , Substância Negra/fisiopatologia , Animais , Sobrevivência Celular/fisiologia , Denervação , Modelos Animais de Doenças , Dopamina/metabolismo , Feminino , Membro Anterior/inervação , Membro Anterior/fisiologia , Masculino , Neurônios/metabolismo , Oxidopamina , Doença de Parkinson/etiologia , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/fisiopatologia , Transtornos Parkinsonianos/terapia , Condicionamento Físico Animal/fisiologia , Gravidez , Ratos , Ratos Sprague-Dawley , Simpatolíticos , Resultado do Tratamento , Tirosina 3-Mono-Oxigenase/metabolismo
16.
J Neural Transm (Vienna) ; 116(7): 791-806, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19504041

RESUMO

The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, simvastatin, is used for lowering elevated low-density lipoprotein cholesterol concentrations. This translates into reduced cardiovascular disease-related morbidity and mortality, while the drugs' anti-oxidant and anti-inflammatory properties have earmarked it as a potential treatment strategy against various neurological conditions. Statins have been shown to protect neurons from degeneration in a number of animal models. Although no mechanism completely explains the multiple benefits exerted by statins, emerging evidence suggests that in some degenerative and brain injury models, mitochondrial impairment may play a contributive rate. However, [corrected] evidence lacks to support a directly influencing role for statins on mitochondria-related proteins and motor behavior. Mitochondrial dysfunction may increase oxygen free radical production, which in turn leaves cells susceptible to energy failure, apoptosis and related events [corrected] which could prove fatal. The potential link between simvastatin treatment and mitochondrial function would be supported if key mitochondrial proteins were altered by simvastatin exposure. Using mass spectroscopy (MS), we identified 24 mitochondrial proteins that differed significantly (P < 0.05) in relative abundancy as a result of simvastatin treatment. The identified proteins represented many facets of mitochondrial integrity, with the majority forming part of the electron transport chain machinery, which is necessary for energy production. In a follow-up study, we then addressed whether simvastatin is capable of altering sensorimotor function in a mitochondrial toxin-induced animal model. Rats were pre-treated with simvastatin for 14 days, followed by a single unihemispheric (substantia nigra; SN) injection of rotenone, a mitochondrial complex I (Co-I) inhibitor. Results showed that simvastatin improved motor performance in rotenone-infused rats. The data are consistent with the possibility that alteration of mitochondrial function may contribute to the beneficial effects associated with statin use.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Mitocôndrias/efeitos dos fármacos , Doenças Mitocondriais/tratamento farmacológico , Proteínas Mitocondriais/efeitos dos fármacos , Doenças Neurodegenerativas/tratamento farmacológico , Proteoma/efeitos dos fármacos , Sinvastatina/farmacologia , Animais , Modelos Animais de Doenças , Complexo de Proteínas da Cadeia de Transporte de Elétrons/efeitos dos fármacos , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Radicais Livres/metabolismo , Masculino , Espectrometria de Massas , Mitocôndrias/metabolismo , Doenças Mitocondriais/metabolismo , Doenças Mitocondriais/fisiopatologia , Proteínas Mitocondriais/metabolismo , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/fisiopatologia , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Proteoma/metabolismo , Proteômica/métodos , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos , Recuperação de Função Fisiológica/fisiologia , Rotenona/farmacologia , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo , Substância Negra/fisiopatologia , Desacopladores/farmacologia
17.
J Neural Transm (Vienna) ; 115(10): 1413-30, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18523721

RESUMO

Despite the vast number of studies on Parkinson's disease (PD), its effective diagnosis and treatment remains unsatisfactory. Hence, the relentless search for an optimal cure continues. The emergence of neuroproteomics, with its sophisticated techniques and non-biased ability to quantify proteins, provides a methodology with which to study the changes in neurons that are associated with neurodegeneration. Neuroproteomics is an emerging tool to establish disease-associated protein profiles, while also generating a greater understanding as to how these proteins interact and undergo post-translational modifications. Furthermore, due to the advances made in bioinformatics, insight is created concerning their functional characteristics. In this review, we first summarize the most prominent proteomics techniques and then discuss the major advances in the fast-growing field of neuroproteomics in PD. Ultimately, it is hoped that the application of this technology will lead towards a presymptomatic diagnosis of PD, and the identification of risk factors and new therapeutic targets at which pharmacological intervention can be aimed.


Assuntos
Neurologia/tendências , Doença de Parkinson , Proteômica/tendências , Animais , Pesquisa Biomédica , Humanos , Neurologia/métodos , Proteômica/métodos
18.
Neurosci Res ; 61(1): 106-12, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18329744

RESUMO

Children that are abused have an increased risk for developing psychiatric disorders later in life, because of the negative effects of stress on the developing brain. We used a maternal separation model in rats to see how neurotrophins, stress hormones, behavior and the anti-oxidant potential of serum are affected. Rat pups were separated from their mothers for 3h/day on days 2-14. Maternal separation caused changes in levels of NGF and NT-3 in the dorsal and ventral hippocampus, increased basal corticosterone levels and decreased ACTH levels after acute restraint stress. The anti-oxidant potential of the rat serum was significantly lower in the maternal separation group. Depressive-like behavior, measured during a forced swim test, was seen in maternally separated rats after additional chronic stress during adulthood. Maternal separation caused downregulation of neurotrophins in the ventral hippocampus, possibly as an effect of high corticosterone levels, but compensatory mechanisms against cell death may be involved as neurotrophin levels increased in the dorsal hippocampus. Decreased anti-oxidant potential of serum could have been an effect of downregulated neurotrophin levels.


Assuntos
Ansiedade de Separação/metabolismo , Ansiedade de Separação/psicologia , Comportamento Animal/fisiologia , Corticosterona/metabolismo , Depressão/metabolismo , Depressão/psicologia , Hipocampo/metabolismo , Privação Materna , Fatores de Crescimento Neural/metabolismo , Estresse Psicológico/metabolismo , Estresse Psicológico/psicologia , Animais , Antioxidantes/metabolismo , Doença Crônica , Hormônio Liberador da Corticotropina/metabolismo , Depressão/etiologia , Sistema Hipotálamo-Hipofisário/fisiopatologia , Hipotálamo/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Restrição Física , Estresse Psicológico/complicações , Natação/psicologia
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