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1.
J Alzheimers Dis ; 99(1): 121-143, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38640149

RESUMO

Background: Previous work from our group has shown that chronic exposure to Vanadium pentoxide (V2O5) causes cytoskeletal alterations suggesting that V2O5 can interact with cytoskeletal proteins through polymerization and tyrosine phosphatases inhibition, causing Alzheimer's disease (AD)-like hippocampal cell death. Objective: This work aims to characterize an innovative AD experimental model through chronic V2O5 inhalation, analyzing the spatial memory alterations and the presence of neurofibrillary tangles (NFTs), amyloid-ß (Aß) senile plaques, cerebral amyloid angiopathy, and dendritic spine loss in AD-related brain structures. Methods: 20 male Wistar rats were divided into control (deionized water) and experimental (0.02 M V2O5 1 h, 3/week for 6 months) groups (n = 10). The T-maze test was used to assess spatial memory once a month. After 6 months, histological alterations of the frontal and entorhinal cortices, CA1, subiculum, and amygdala were analyzed by performing Congo red, Bielschowsky, and Golgi impregnation. Results: Cognitive results in the T-maze showed memory impairment from the third month of V2O5 inhalation. We also noted NFTs, Aß plaque accumulation in the vascular endothelium and pyramidal neurons, dendritic spine, and neuronal loss in all the analyzed structures, CA1 being the most affected. Conclusions: This model characterizes neurodegenerative changes specific to AD. Our model is compatible with Braak AD stage IV, which represents a moment where it is feasible to propose therapies that have a positive impact on stopping neuronal damage.


Assuntos
Doença de Alzheimer , Encéfalo , Modelos Animais de Doenças , Memória Espacial , Compostos de Vanádio , Animais , Masculino , Administração por Inalação , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/patologia , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/patologia , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/patologia , Angiopatia Amiloide Cerebral/induzido quimicamente , Angiopatia Amiloide Cerebral/patologia , Espinhas Dendríticas/efeitos dos fármacos , Espinhas Dendríticas/patologia , Córtex Entorrinal/efeitos dos fármacos , Córtex Entorrinal/patologia , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/patologia , Aprendizagem em Labirinto/efeitos dos fármacos , Emaranhados Neurofibrilares/efeitos dos fármacos , Emaranhados Neurofibrilares/patologia , Placa Amiloide/induzido quimicamente , Placa Amiloide/patologia , Ratos Wistar , Memória Espacial/efeitos dos fármacos , Compostos de Vanádio/administração & dosagem , Compostos de Vanádio/toxicidade
2.
Behav Brain Res ; 465: 114928, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38432301

RESUMO

Testosterone (T), estrogen receptor alpha (ERα), and androgen receptor (AR) play a significant role in the regulation of paternal behavior. We determined the effects of deprivation of paternal care on alterations in paternal behavior, T concentrations in plasma, and the presence of ERα and AR in the medial preoptic area (mPOA), bed nucleus of the stria terminalis (BNST), medial amygdala (MeA), and olfactory bulb (OB), as well as the corticosterone (CORT) concentrations in plasma caused by deprivation of paternal care in the Mongolian gerbil (Meriones unguiculatus). Twenty pairs of gerbils were formed; the pups were deprived of paternal care (DPC) in 10 pairs. In another 10 pairs, the pups received paternal care (PC). Ten males raised in DPC condition and 10 males raised in PC conditions were mated with virgin females. When they became fathers, each DPC male and PC male was subjected to tests of paternal behavior on day three postpartum. Blood samples were obtained to quantify T and CORT concentrations, and the brains were removed for ERα and AR immunohistochemistry analyses. DPC males gave less care to their pups than PC males, and they had significantly lower T concentrations and levels of ERα and AR in the mPOA and BNST than PC males. DPC males also had higher CORT concentrations than PC males. These results suggest that in the Mongolian gerbil father's absence causes a decrease in paternal care in the offspring, which is associated with alterations in the neuroendocrine mechanisms that regulate it.


Assuntos
Receptores Androgênicos , Núcleos Septais , Animais , Feminino , Masculino , Humanos , Gerbillinae/fisiologia , Receptores Androgênicos/metabolismo , Núcleos Septais/metabolismo , Receptor alfa de Estrogênio/metabolismo , Comportamento Paterno/fisiologia , Área Pré-Óptica/metabolismo , Pai , Corticosterona
3.
Nutr. clín. diet. hosp ; 44(1): 310-317, Feb. 2024. ilus, tab, graf
Artigo em Espanhol | IBECS | ID: ibc-231327

RESUMO

Introducción: En años reciente se señalado que trastor-nos como la obesidad, la diabetes mellitus tipo 2 (DMT-II) es-tán asociados a deterioro cognitivo. Una posibilidad para com-prender la relación entre la cognición y estos trastornos sonlos biomarcadores en sangre. Objetivo: El objetivo de esta investigación fue determinarla relación de la hemoglobina glucosilada (HbA1c) y lípidoscon el desempeño cognitivo de pacientes que están expues-tos varios factores de riesgo vascular en comparación con pa-cientes que tienen menos factores de riesgo. Metodología: Se llevó a cabo un muestreo no probabilís-tico por conveniencia. Se consideraron a adultos de ambossexos que tuvieran una edad mayor a 18 años y que conta-ran con algún factor de riesgo como un estilo de vida seden-tario y/o diagnóstico de DMT-II, hipertensión u obesidad. Losparticipantes (n=28) fueron evaluados mediante EvaluaciónCognitiva Montreal (MoCA) y tareas para evaluar memoria detrabajo verbal y visoespacial (Dspan y Mspan). Asimismo, sedeterminaron los niveles de hemoglobina glicosilada (HbA1c),colesterol (HDL y LDL) y triglicéridos (TG). Resultados: Se encontró que los niveles elevados deHbA1c y TG se asociaron con una menor puntuación en laprueba MoCA, mientras que los niveles elevados de HDL seasociaron con mejor desempeño cognitivo en dicha prueba.Al dividir a la muestra en función de la cantidad de factoresde riesgo vascular a los que han sido expuestos se encon-tró que a mayor presencia de factores de riesgo la relaciónde la HbA1c y TG con un menor desempeño cognitivo esmás fuerte. Conclusión: Se concluye que la relación entre biomarca-dores y funciones cerebrales es fuerte y dependiente de lacantidad de factores de riesgo vascular a los que están ex-puestos los pacientes.(AU)


Introduction: In recent years it has been reported thatdisorders such as obesity and type 2 diabetes mellitus (T2DM)are associated with cognitive impairment. One possibility tounderstand the relationship between cognition and these dis-orders is blood biomarkers. Objective: The aim of this research was to determine therelationship of glycosylated hemoglobin (HbA1c) and lipidswith cognitive performance in patients who are exposed tovarious vascular risk factors compared with patients who havefewer risk factors. Methodology: Non-probability convenience sampling wasperformed. Adults of both sexes who were older than 18 years of age and who had some risk factor such as a sedentarylifestyle and/or diagnosis of T2DM, hypertension, or obesitywere considered. Participants (n=28) were assessed byMontreal Cognitive Assessment (MoCA) and tasks to evaluateverbal and visuospatial working memory (Dspan and Mspan).Glycosylated hemoglobin (HbA1c), cholesterol (HDL and LDL)and triglycerides (TG) levels were also determined. Results: It was found that elevated HbA1c and TG levelswere associated with a lower score on the MoCA test, whileelevated HDL levels were associated with better cognitive per-formance on the MoCA test. When the sample was divided ac-cording to the number of vascular risk factors to which theyhad been exposed, it was found that the greater the presenceof risk factors the stronger the relationship of HbA1c and TGwith poorer cognitive performance. Conclusion: We conclude that the relationship betweenbiomarkers and brain function is strong and dependent on thenumber of vascular risk factors to which patients are exposed.(AU)


Assuntos
Humanos , Masculino , Feminino , Cognição , Biomarcadores , Lipídeos , Obesidade , Diabetes Mellitus Tipo 2 , Ciências da Nutrição , Estilo de Vida , Glucose , Alimentos, Dieta e Nutrição
4.
Front Oncol ; 13: 1210297, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37941543

RESUMO

Currently, immunotherapy based on PD-1/PD-L1 pathway blockade has improved survival of non-small cell lung cancer (NSCLC) patients. However, differential responses have been observed by sex, where men appear to respond better than women. Additionally, adverse effects of immunotherapy are mainly observed in women. Studies in some types of hormone-dependent cancer have revealed a role of sex hormones in anti-tumor response, tumor microenvironment and immune evasion. Estrogens mainly promote immune tolerance regulating T-cell function and modifying tumor microenvironment, while androgens attenuate anti-tumor immune responses. The precise mechanism by which sex and sex hormones may modulate immune response to tumor, modify PD-L1 expression in cancer cells and promote immune escape in NSCLC is still unclear, but current data show how sexual differences affect immune therapy response and prognosis. This review provides update information regarding anti-PD-1/PD-L immunotherapeutic efficacy in NSCLC by sex, analyzing potential roles for sex hormones on PD-L1 expression, and discussing a plausible of sex and sex hormones as predictive response factors to immunotherapy.

5.
Heliyon ; 7(8): e07856, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34471719

RESUMO

Vanadium (V) toxicity depends on its oxidation state; it seems that vanadium pentoxide (V2O5) is the most toxic to the living cells. It has been reported that oral administration induces changes in motor activity and learning; in rats, I.P. administration increases lipid peroxidation levels in the cerebellum and the concentration of free radicals in the hippocampus and cerebellum. Mice that inhaled V2O5 presented a reduced number of tubulin+ in Leydig and Sertoli cells; it has also been reported that inhaled V2O5 induces loss of dendritic spines, necrosis, and hippocampus neuropil alterations; considering the direct consequence of the interaction of V with cytoskeletal components, makes us believe that V2O5 exposure could cause neuronal death in the hippocampus similar to that seen in Alzheimer disease. This work aimed to determine pyramidal hippocampal CA1 cytoskeletal alterations with Bielschowsky stain in rats exposed to V2O5. Male Wistar rats inhaled 0.02 M of V2O5 one h two times a week for two and six months. We found that rats, which inhaled V2O5 reached 56,57% of dead neurons after six months of inhalation; we recognize strong argyrophilic and collapsed somas and typical flame-shaped in all V-exposed rats hippocampus CA1 compared to controls. We also observe somatodendritic distortions. Axons and dendrites displayed thick dark bands replaced by noticeable thickening and nodosities and the cytoskeleton fibrillary proteins' linear traces. Our findings suggest that V2O5 inhalation induces Alzheimer-like cell death with evident cytoskeletal alterations.

6.
Front Med (Lausanne) ; 8: 600121, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34079807

RESUMO

Lung cancer incidence and mortality have significantly increased in women worldwide. Lung adenocarcinoma is the most common form of lung cancer globally. This type of lung cancer shows differences by sex, including the mutational burden, behavior, clinical characteristics, and response to treatment. The effect of sex on lung cancer patients' survival is still controversial; however, lung adenocarcinoma is considered a different disease in women and men. Moreover, lung adenocarcinoma is strongly influenced by estrogen and is also different depending on the hormonal status of the patient. Young pre-menopausal women have been explored as an independent group. They presented in more advanced stages at diagnosis, exhibited more aggressive tumors, and showed poor survival compared to men and post-menopausal women, supporting the role of sex hormones in this pathology. Several reports indicate the estrogen's role in lung carcinogenesis and tumor progression. Thus, there are currently some clinical trials testing the efficacy of antihormonal therapy in lung cancer treatment. This mini review shows the updated data about lung cancer in women, its characteristics, the etiological factors that influence carcinogenesis, and the critical role of estrogen in lung cancer and treatment.

7.
Pathogens ; 9(6)2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32526974

RESUMO

Amoebae of the genus Acanthamoeba are etiological agents of granulomatous amoebic encephalitis (GAE). Recently, through an in vivo GAE model, Acanthamoeba trophozoites were immunolocalized in contact with the peripheral nervous system (PNS) cells-Schwann cells (SC). In this study, we analyzed in greater detail the in vitro early morphological events (1, 2, 3, and 4 h) during the interaction of A. culbertsoni trophozoites (ATCC 30171) with SC from Rattus norvegicus (ATCC CRL-2941). Samples were processed for scanning and transmission electron microscopy as well as confocal microscopy. After 1 h of interaction, amoebae were observed to be adhered to the SC cultures, emitting sucker-like structures associated with micro-phagocytic channels. In addition, evidence of necrosis was identified since edematous organelles as well as multivesicular and multilamellar bodies characteristics of autophagy were detected. At 2 h, trophozoites migrated beneath the SC culture in which necrosis and autophagy persisted. By 3 and 4 h, extensive lytic zones were observed. SC necrosis was confirmed by confocal microscopy. We reported for the first time the induction of autophagic and necrotic processes in PNS cells, associated in part with the contact-dependent pathogenic mechanisms of A. culbertsoni trophozoites.

8.
Microscopy (Oxf) ; 63(6): 427-35, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25246608

RESUMO

Synaptic plasticity is the process by which long-lasting changes take place at synaptic connections. The phenomenon itself is complex and can involve many levels of organization. Some authors separate forms into adaptations that have positive or negative consequences for the individual. It has been hypothesized that an increase in the number of synapses may represent a structural basis for the enduring expression of synaptic plasticity during some events that involve memory and learning; also, it has been suggested that perforated synapses increase in number after some diseases and experimental situations. The aim of this study was to analyze whether dopamine depletion induces changes in the synaptology of the corpus striatum of rats after the unilateral injection of 6-OHDA. The findings suggest that after the lesion, both contralateral and ipsilateral striata exhibit an increased length of the synaptic ending in ipsilateral (since third day) and contralateral striatum (since Day 20), loss of axospinous synapses in ipsilateral striatum and a significant increment in the number of perforated synapses, suggesting brain plasticity that might be deleterious for the spines, because this type of synaptic contacts are presumably excitatory, and in the absence of the modulatory effects of dopamine, the neuron could die through excitotoxic mechanisms. Thus, we can conclude that the presence of perforated synapses after striatal dopamine depletion might be a form of maladaptive synaptic plasticity.


Assuntos
Corpo Estriado/ultraestrutura , Dopamina/fisiologia , Plasticidade Neuronal , Sinapses/ultraestrutura , Animais , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/fisiologia , Dopamina/deficiência , Masculino , Microscopia Eletrônica , Plasticidade Neuronal/fisiologia , Oxidopamina/farmacologia , Ratos , Ratos Wistar , Sinapses/efeitos dos fármacos , Sinapses/fisiologia
9.
Neurosci Lett ; 556: 227-31, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24511608

RESUMO

Comparative anatomy has shown similarities between reptilian and mammalian basal ganglia. Here the morphological characteristics of the medium spiny neurons (MSN) in the dorsolateral striatum (DLS) of the turtle are described after staining them with the Golgi technique. The soma of MSN in DLS showed three main forms: spherical, ovoid, and fusiform. The number of primary dendritic branches (3-4 den-drites/cell) was less than observed in mammals. The MSN axon originates mainly from the soma, and randomly it emerges at the beginning of the primary dendrite. The main differences between turtle and mammalian MSN were detected on dendritic spines. Short, thin, bifurcated and fungiform types of den-dritic spines were observed in the turtle's MSN, according to their shape. In most of the analyzed spines,it was found that its length considerably exceeded that reported in mammals, with dendritic spines upto 8 µm in length. These differences could play an important role in the modulation of motor networks preserved along the vertebrate evolution.


Assuntos
Corpo Estriado/citologia , Complexo de Golgi/ultraestrutura , Neurônios/ultraestrutura , Tartarugas/anatomia & histologia , Animais , Espinhas Dendríticas/ultraestrutura
10.
Neurotoxicology ; 33(5): 1346-55, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22975423

RESUMO

Manganese (Mn) is an essential trace metal. Regardless of its essentiality, it has been reported that the overexposure causes neurotoxicity manifested as extrapyramidal symptoms similar to those observed in Parkinson disease (PD). Recently, our group reported that mice that inhaled for 5 months the mixture of manganese chloride (MnCl(2)) and manganese acetate Mn(OAc)(3) developed movement abnormalities, significant loss of substantia nigra compacta (SNc) dopaminergic neurons, dopamine depletion and improved behavior with l-DOPA treatment. However, this model has only been characterized in mice. In order to have a well-supported and generalizable model in rodents, we used male Wistar rats that inhaled a mixture of 0.04 M MnCl(2) and 0.02 M Mn(OAc)(3), 1h three times a week for 6 months. Before Mn exposure, animals were trained to perform motor tests (Beam-walking and Single-pellet reaching tasks) and were evaluated each week after the exposure. The mixture of MnCl(2)/Mn(OAc)(3) caused alterations in the motor tests, 75.95% loss of SNc dopaminergic neurons, and no cell alterations in Globus Pallidus or striatum. With these results we conclude that the inhalation of the mixture of Mn compounds is a useful model in rodents for the study of PD.


Assuntos
Modelos Animais de Doenças , Intoxicação por Manganês/complicações , Doença de Parkinson/etiologia , Administração por Inalação , Análise de Variância , Animais , Antiparkinsonianos/uso terapêutico , Encéfalo/metabolismo , Encéfalo/patologia , Comportamento Alimentar/efeitos dos fármacos , Levodopa/uso terapêutico , Locomoção/efeitos dos fármacos , Masculino , Compostos de Manganês/administração & dosagem , Camundongos , Atividade Motora/efeitos dos fármacos , Exame Neurológico , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/patologia , Fosfopiruvato Hidratase/metabolismo , Desempenho Psicomotor/efeitos dos fármacos , Ratos , Ratos Wistar , Tirosina 3-Mono-Oxigenase/metabolismo , Gravação em Vídeo
11.
Exp Neurol ; 236(1): 131-40, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22542948

RESUMO

Lafora disease (LD) is an autosomal recessive, always fatal progressive myoclonus epilepsy with rapid cognitive and neurologic deterioration. One of the pathological hallmarks of LD is the presence of cytoplasmic PAS+polyglucosan inclusions called Lafora bodies (LBs). Current clinical and neuropathological views consider LBs to be the cause of neurological derangement of patients. A systematic study of the ontogeny and structural features of the LBs has not been done in the past. Therefore, we undertook a detailed microscopic analysis of the neuropile of a Laforin-deficient (epm2a-/-) mouse model. Wild type and epm2a-/- mice were sacrificed at different ages and their encephalon processed for light microscopy. Luxol-fast-blue, PAS, Bielschowski techniques, as well as immunocytochemistry (TUNEL, Caspase-3, Apaf-1, Cytochrome-C and Neurofilament L antibodies) were used. Young null mice (11 days old) showed necrotic neuronal death in the absence of LBs. Both cell death and LBs showed a progressive increment in size and number with age. Type I LBs emerged at two weeks of age and were distributed in somata and neurites. Type II LBs appeared around the second month of age and always showed a complex architecture and restricted to neuronal somata. Their number was considerably less than type I LBs. Bielschowski method showed neurofibrillary degeneration and senile-like plaques. These changes were more prominent in the hippocampus and ventral pons. Neurofibrillary tangles were already present in 11 days-old experimental animals, whereas senile-like plaques appeared around the third to fourth month of life. The encephalon of null mice was not uniformly affected: Diencephalic structures were spared, whereas cerebral cortex, basal ganglia, pons, hippocampus and cerebellum were notoriously affected. This uneven distribution was present even within the same structure, i.e., hippocampal sectors. Of special relevance, was the observation of the presence of immunoreactivity to neurofilament L on the external rim of type II LBs. Perhaps, type II LB is not the end point of a metabolic abnormality. Instead, we suggest that type II LB is a highly specialized structural and functional entity that emerges as a neuronal response to major carbohydrate metabolism impairment. Early necrotic cell death, neurocytoskeleton derangement, different structural and probably functional profiles for both forms of LBs, a potential relationship between the external rim of the LB type II and the cytoskeleton and an uneven distribution of these abnormalities indicate that LD is both a complex neurodegenerative disease and a glycogen metabolism disorder. Our findings are critical for future studies on disease mechanisms and therapies for LD. Interestingly, the neurodegenerative changes observed in this LD model can also be useful for understanding the process of dementia.


Assuntos
Citoesqueleto/patologia , Fosfatases de Especificidade Dupla/genética , Doença de Lafora/genética , Doença de Lafora/patologia , Degeneração Neural/patologia , Neurônios/patologia , Animais , Gânglios da Base/patologia , Tronco Encefálico/patologia , Citoplasma/patologia , Modelos Animais de Doenças , Feminino , Hipocampo/patologia , Doença de Lafora/metabolismo , Masculino , Camundongos , Camundongos Mutantes , Degeneração Neural/genética , Degeneração Neural/metabolismo , Emaranhados Neurofibrilares/patologia , Neurópilo/patologia , Fenótipo , Placa Amiloide/patologia , Proteínas Tirosina Fosfatases não Receptoras , Área Tegmentar Ventral/patologia
12.
ISRN Neurol ; 2012: 360379, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22462019

RESUMO

The present study examines the ability of melatonin to protect striatal dopaminergic loss induced by 6-OHDA in a rat model of Parkinson's disease, comparing the results with L-DOPA-treated rats. The drugs were administered orally daily for a month, their therapeutic or dyskinetic effects were assessed by means of abnormal involuntary movements (AIMs) and stepping ability. At the cellular level, the response was evaluated using tyrosine hydroxylase immunoreactivity and striatal ultrastructural changes to compare between L-DOPA-induced AIMs and Melatonin-treated rats. Our findings demonstrated that chronic oral administration of Melatonin improved the alterations caused by the neurotoxin 6-OHDA. Melatonin-treated animals perform better in the motor tasks and had no dyskinetic alterations compared to L-DOPA-treated group. At the cellular level, we found that Melatonin-treated rats showed more TH-positive neurons and their striatal ultrastructure was well preserved. Thus, Melatonin is a useful treatment to delay the cellular and behavioral alterations observed in Parkinson's disease.

13.
Neurosci Lett ; 471(2): 79-82, 2010 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-20079802

RESUMO

This investigation was designed to determine whether l-DOPA treatment improves the motor alterations observed after divalent and trivalent manganese (Mn) mixture inhalation on mice to ensure that the alterations are of dopaminergic origin. CD-1 male mice inhaled a mixture of 0.04 M manganese chloride (MnCl(2)) and manganese acetate (Mn(OAc)(3)), 1h twice a week for 5 months. Before Mn exposure, animals were trained to perform motor function tests and were evaluated each week after the exposure. Overall behavior was assessed by ratings and by videotaped analyses; by the end of Mn exposure period, 10 mice were orally treated with 7.5mg/kg L-DOPA. After 5 months of Mn-mixture inhalation striatal dopamine content decreased 71%, mice developed evident deficits in motor performance manifested as akinesia, postural instability and action tremor; these alterations were reverted with L-DOPA treatment. Our results suggest that the motor alterations induced by the inhalation of the combination of MnCl(2)/Mn(OAc)(3) are related to nigrostriatal dopaminergic function providing new light on the understanding of manganese neurotoxicity as a suitable Parkinson disease experimental model.


Assuntos
Acetatos , Antiparkinsonianos/uso terapêutico , Cloretos , Modelos Animais de Doenças , Levodopa/uso terapêutico , Compostos de Manganês , Atividade Motora/efeitos dos fármacos , Compostos Organometálicos , Doença de Parkinson/tratamento farmacológico , Administração por Inalação , Animais , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Dopamina/metabolismo , Masculino , Camundongos , Doença de Parkinson/etiologia , Doença de Parkinson/fisiopatologia
14.
Parkinsons Dis ; 2011: 612989, 2010 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-21209715

RESUMO

The present study examines the effects of divalent and trivalent Manganese (Mn(2+)/Mn(3+)) mixture inhalation on mice to obtain a novel animal model of Parkinson disease (PD) inducing bilateral and progressive dopaminergic cell death, correlate those alterations with motor disturbances, and determine whether L-DOPA treatment improves the behavior, to ensure that the alterations are of dopaminergic origin. CD-1 male mice inhaled a mixture of Manganese chloride and Manganese acetate, one hour twice a week for five months. Before Mn exposure, animals were trained to perform motor function tests and were evaluated each week after the exposure. By the end of Mn exposure, 10 mice were orally treated with 7.5 mg/kg L-DOPA. After 5 months of Mn mixture inhalation, striatal dopamine content decreased 71%, the SNc showed important reduction in the number of TH-immunopositive neurons, mice developed akinesia, postural instability, and action tremor; these motor alterations were reverted with L-DOPA treatment. Our data provide evidence that Mn(2+)/Mn(3+) mixture inhalation produces similar morphological, neurochemical, and behavioral alterations to those observed in PD providing a useful experimental model for the study of this neurodegenerative disease.

15.
Reprod Toxicol ; 23(4): 588-92, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17462858

RESUMO

Vanadium (V) is a transition metal emitted to the atmosphere during the combustion of fossil fuels. Its current status as an atmospheric pollutant increases the need for information about the effects that this element might have on the reproductive health of exposed populations. The present study investigated changes in testicular ultrastructure following inhalation exposure of male mice to V (as vanadium pentoxide). Tissue V level was constant during the 12-week time period. We observed necrosis of spermatogonium, spermatocytes and Sertoli cells, as well as pseudo-nuclear inclusion and disruption of cellular junctions. Our findings stressed the importance of the hemato-testicular barrier in supporting the function of Sertoli cells and suggest as a possible target of V, tight junction proteins. Further analysis is needed in order to identify the role that reactive oxidative species (ROS) might have on these cellular junctions, and if a specific protein is the target of its toxic effects. The relevance of this report concerns the impact that metal air pollution could have on male fertility in dense cities with vehicular traffic problems.


Assuntos
Poluentes Atmosféricos/toxicidade , Exposição por Inalação , Testículo/efeitos dos fármacos , Testículo/ultraestrutura , Compostos de Vanádio/toxicidade , Poluentes Atmosféricos/metabolismo , Animais , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/ultraestrutura , Infertilidade Masculina/induzido quimicamente , Masculino , Camundongos , Microscopia Eletrônica , Necrose , Túbulos Seminíferos/efeitos dos fármacos , Túbulos Seminíferos/ultraestrutura , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/ultraestrutura , Espermatócitos/efeitos dos fármacos , Espermatócitos/ultraestrutura , Espermatogônias/efeitos dos fármacos , Espermatogônias/ultraestrutura , Testículo/metabolismo , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/ultraestrutura , Fatores de Tempo , Compostos de Vanádio/metabolismo
16.
Neurotoxicology ; 27(6): 1007-12, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16684564

RESUMO

Spatial memory may be severely impaired as a consequence of ageing and neurodegenerative diseases, conditions that include neuronal damage. Vanadium (V) is a metalloid widely distributed in the environment and exerts severe toxic effects on a wide variety of biological systems. Reports about V inhalation toxicity on the CNS are limited, thus the purpose of this study is to determine the effects of Vanadium pentoxide (V(2)O(5)) inhalation (0.02M) on the memory and its correlation with the cytology of the hippocampus CA1. Forty eight CD-1 male mice were trained in spatial memory tasks and inhaled 1h twice a week; after each inhalation animals were evaluated and sacrificed from 1 to 4 weeks, perfused and processed for Golgi method and for ultrastructure evaluation. The cytological analysis consisted in counting the number of dendritic spines of 20 pyramidal neurons of hippocampus CA1, as well as ultrastructural characteristics. Results show that V inhalation produces a time dependent loss of dendritic spines, necrotic-like cell death, and notorious alterations of the hippocampus CA1 neuropile, which correlate with spatial memory impairment. Our data suggest that V induces important cellular and functional alterations, fact that deserves special attention since the concentration's trend of this element in the atmosphere is increasing.


Assuntos
Hipocampo , Transtornos da Memória/induzido quimicamente , Células Piramidais/efeitos dos fármacos , Compostos de Vanádio/administração & dosagem , Administração por Inalação , Análise de Variância , Animais , Comportamento Animal/efeitos dos fármacos , Dendritos/efeitos dos fármacos , Dendritos/ultraestrutura , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Hipocampo/ultraestrutura , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Microscopia Eletrônica de Transmissão/métodos , Células Piramidais/ultraestrutura , Tempo de Reação/efeitos dos fármacos , Coloração pela Prata/métodos , Fatores de Tempo
17.
Toxicol Ind Health ; 22(3): 113-6, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16716040

RESUMO

Reports about vanadium (V) inhalation toxicity on the hematopoietic system, specifically about coagulation are limited. Therefore, we decided to evaluate the effects of V with a complete blood count and morphologic analysis of platelets on blood smears. CD-1 male mice inhaled V2O5 0.02 M 1 h twice weekly over 12 weeks. Blood samples were obtained by direct heart puncture; Wright stained smears were used for platelet quantification. An increase in platelet count from the third week of exposure was observed, as well as the presence of megaplatelets. Our results demonstrate, for the first time, that V induces thrombocytosis and it might correlate with some thromboembolic diseases. Further analysis is needed to evaluate the functionality of these platelets as well as the cause of its increase.


Assuntos
Poluentes Atmosféricos/toxicidade , Trombocitose/induzido quimicamente , Compostos de Vanádio/toxicidade , Administração por Inalação , Animais , Masculino , Camundongos , Compostos de Vanádio/administração & dosagem
18.
Environ Res ; 100(2): 227-31, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16442996

RESUMO

The relation of blood Pb concentrations and renal dysfunction has been reported in association with interstitial fibrosis, tubular atrophy, and decreased glomerular filtration. In this report information about blood Pb concentrations and renal function tests in a population from Oaxaca, Mexico is analyzed. The main changes found were that males had higher blood Pb concentrations than females (P<0.0012); the leading variables associated with this were occupation (glazed pottery workers, P=0.0001) and the use of glazed pottery for preparing meals (P=0.0000). Variables that better explain uric acid variability were blood Pb concentrations, sex, weight, and height (r2=0.23). Hyperuricemia was associated with blood Pb concentrations above 40 microg/dL (OR=1.74, 95% CI, 1.12-2.61). SCr was associated with sex, age, and blood Pb, with coefficient r2=0.12. Our findings might be related to inadequate control of oven emissions, a situation that will require further analysis and the implementation of preventive measurements for the nonoccupational exposed population.


Assuntos
Exposição Ambiental/efeitos adversos , Nefropatias/induzido quimicamente , Intoxicação por Chumbo/sangue , Chumbo/sangue , Adulto , Proteínas Sanguíneas/metabolismo , Utensílios de Alimentação e Culinária , Creatinina/sangue , Estudos Transversais , Feminino , Humanos , Rim/efeitos dos fármacos , Nefropatias/sangue , Testes de Função Renal , Intoxicação por Chumbo/fisiopatologia , Masculino , México , Albumina Sérica/metabolismo , Inquéritos e Questionários , Ureia/sangue , Ácido Úrico/sangue
19.
Toxicol Ind Health ; 21(9): 215-22, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16342472

RESUMO

Vanadium is an important environmental and industrial pollutant whose concentrations have increased in the last decades. Due to its status as reproductive toxicant and a microtubule damaging agent, the present study investigated by immunohistochemistry the effect of the inhalation of vanadium pentoxide on gamma-tubulin within somatic and testicular germ cells. Male mice inhaled vanadium pentoxide (V2O5) (0.02 M) 1 h/twice a week for 12 weeks. Our results demonstrated that vanadium accumulates in the testes starting with the initial inhalation (24 h), and this pattern remained until the last week of treatment. In general, vanadium was capable of significantly decreasing the percentage of gamma-tubulin in all analyzed testicular cells (Sertoli, Leydig and germ cells) starting with the first week of treatment. For all cell types studied, regression analysis revealed a negative and significant relationship between the percentage of immunopositive cells to gamma-tubulin and exposure time, showing a time dependent response in all cases. Our findings suggest that alterations on this protein might imply changes in microtubule-involved function such as cell division, which in the testes might lead to damage in the spermatogenesis, leading probably to infertility.


Assuntos
Exposição por Inalação , Testículo/efeitos dos fármacos , Tubulina (Proteína)/efeitos dos fármacos , Compostos de Vanádio/toxicidade , Administração por Inalação , Poluentes Atmosféricos/toxicidade , Animais , Citoesqueleto/efeitos dos fármacos , Células Germinativas/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos , Testículo/citologia , Fatores de Tempo , Tubulina (Proteína)/metabolismo
20.
Int J Neurosci ; 115(6): 851-9, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16019578

RESUMO

The objective of this article was to identify the effects of bromocriptine on the ultrastructure of the caudate nucleus in rats with a 6-hydroxidopamine (6-OHDA) unilateral lesion of the substantia nigra pars compacta. Eighteen Wistar male rats were stereotactically lesioned with 6-OHDA (n=12), or sham lesioned (n=6). Two days after rotational behavior was tested, and 2 days later, 6 rats were treated with 0.3 mg/Kg bromocriptine orally for a month and 6 rats were kept for the same time without treatment. The neuropile of the sham operated and bromocriptine-treated rats was well preserved contrary to the non-bromocriptine-treated rats. Also, it was found that there was a significant difference in the number of synaptic endings with edema in caudate of bromocriptine-treated rats compared with non-treated rats; however, the size of the synaptic endings were different to those found in the sham lesioned rats. Also, as in the sham lesioned group, the bromocriptines showed more synaptic contacts with dendritic spines contrasting to the non-treated group. The results suggest that bromocriptine possesses antioxidant properties because it decreased the ultrastructural alterations after 6-OHDA lesion.


Assuntos
Antiparkinsonianos/uso terapêutico , Bromocriptina/uso terapêutico , Núcleo Caudado/metabolismo , Núcleo Caudado/ultraestrutura , Modelos Animais de Doenças , Dopamina/metabolismo , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Animais , Masculino , Placa Motora/metabolismo , Placa Motora/ultraestrutura , Estresse Oxidativo/fisiologia , Doença de Parkinson/diagnóstico , Ratos , Ratos Wistar
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