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Objectives Meningiomas (MNGs) are the most common intracranial tumors found in the adult population. While most intracranial MNGs may be surgically removed, a subset of patients remains ineligible for conventional treatment. This is either because of a lack of surgical access or due to atypical, anaplastic or invasive characteristics of the tumors. These patients may benefit from targeted therapies that focus on cell receptor expression. The aim of this study was to assess dopamine receptor (DR) and Ki-67 expression in the MGNs of patients treated with surgery in the Instituto Nacional de Neurología y Neurocirugía, Mexico. Materials and methods This study analyzed 23 patients with confirmed MNG diagnoses (10 female and 13 male (mean age: 44.5 years)) who had undergone surgical resection between 2010 and 2014 at our institution. In the collected samples, we performed analyses for Ki-67, Dopamine 1 and Dopamine 2 receptors' expression. Results For the markers Ki-67, DR-D1 and DR-D2, the mean percentual expressions were 18.9%, 23.02% and 8.33%. No significant correlation was found between the expressions of these receptors and the studied MNG characteristics. The expression index of Ki-67 showed a significant relation with mean age (p = 0.03) and prolactin levels (p = 0.02). Conclusions Samples showed varied expressions of the studied receptors. Despite the difference in expressions between the markers, more studies are needed to confirm the findings. In contrast to previous studies, we could not find any relationship between D2-R and tumor characteristics.
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A glioblastoma is an aggressive form of a malignant glial-derived tumor with a poor prognosis despite multimodal therapy approaches. Lactate has a preponderant role in the tumor microenvironment, playing an immunoregulatory role as well as being a carbon source for tumor growth. Lactate homeostasis depends on the proper functioning of intracellular lactate regulation systems, such as transporters and enzymes involved in its synthesis and degradation, with evidence that an intracellular lactate overload generates metabolic stress on tumor cells and tumor cell death. We propose that the delivery of a lactate overload carried in nanoparticles, allowing the intracellular release of lactate, would compromise the survival of tumor cells. We synthesized and characterized silica and titania nanoparticles loaded with lactate to evaluate the cellular uptake, metabolic activity, pH modification, and cytotoxicity on C6 cells under normoxia and chemical hypoxia, and, finally, determined the survival of an orthotopic malignant glioma model after in situ administration. A dose-dependent reduction in metabolic activity of treated cells under normoxia was found, but not under hypoxia, independent of glucose concentration. Lactated-loaded silica nanoparticles were highly cytotoxic (58.1% of dead cells) and generated significant supernatant acidification. In vivo, lactate-loaded silica nanoparticles significantly increased the median survival time of malignant glioma-bearing rats (p = 0.005) when administered in situ. These findings indicate that lactate-loaded silica nanoparticles are cytotoxic on glioma cells in vitro and in vivo.
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Pituitary adenomas (PAs) can be unpredictable and aggressive tumors. No reliable markers of their biological behavior have been found. Here, a proteomic analysis was applied to identify proteins in the expression profile between invasive and non-invasive PAs to search for possible biomarkers. A histopathological and immunohistochemical (adenohypophyseal hormones, Ki-67, p53, CD34, VEGF, Flk1 antibodies) analysis was done; a proteomic map was evaluated in 64 out of 128 tumors. There were 107 (84%) invasive and 21 (16%) non-invasive PAs; 80.5% belonged to III and IV grades of the Hardy-Vezina classification. Invasive PAs (n = 56) showed 105 ± 43 spots; 86 ± 32 spots in non-invasive PAs (n = 8) were observed. The 13 most prominent spots were selected and 11 proteins related to neoplastic process in different types of tumors were identified. Hint1 (Histidine triad nucleotide-binding protein 1) high expression in invasive PA was found (11.8 ± 1.4, p = 0.005), especially at high index (>10; p = 0.0002). High Hint1 expression was found in invasive VEGF positive PA (13.8 ± 2.3, p = 0.005) and in Flk1 positive PA (14.04 ± 2.28, p = 0.006). Hint1 is related to human tumorigenesis by its interaction with signaling pathways and transcription factors. It could be related to invasive behavior in PAs. This is the first report on Hint expression in PAs. More analysis is needed to find out the possible role of Hint in these tumors.
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Glucose transporter (GLUT)3 up-regulation is an adaptive response activated to prevent cellular damage when brain metabolic energy is reduced. Resveratrol is a natural polyphenol with anti-oxidant and anti-inflammatory features that protects neurons against damage induced in cerebral ischemia. Since transcription factors sensitive to oxidative stress and inflammation modulate GLUT3 expression, the purpose of this work was to assess the effect of resveratrol on GLUT3 expression levels after ischemia. Male Wistar rats were subjected to 2 h of middle cerebral artery occlusion (MCAO) followed by different times of reperfusion. Resveratrol (1.9 mg/kg; i. p.) was administered at the onset of the restoration of the blood flow. Quantitative-PCR and Western blot showed that MCAO provoked a substantial increase in GLUT3 expression in the ipsilateral side to the lesion of the cerebral cortex. Immunofluorescence assays indicated that GLUT3 levels were upregulated in astrocytes. Additionally, an important increase in GLUT3 occurred in other cellular types (e.g., damaged neurons, microglia, or infiltrated macrophages). Immunodetection of the microtubule-associated protein 2 (MAP2) showed that MCAO induced severe damage to the neuronal population. However, the administration of resveratrol at the time of reperfusion resulted in injury reduction. Resveratrol also prevented the MCAO-induced increase of GLUT3 expression. In conclusion, resveratrol protects neurons from damage induced by ischemia and prevents GLUT3 upregulation in the damaged brain that might depend on AMPK activation.
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This study aimed to compare the antioxidant activities of extracts obtained from three plant families and evaluate their therapeutic effect on strokes. Ethanol extracts were obtained from either the leaf or the aerial parts of plants of the families Annonaceae (Annona cherimola, A. diversifolia, A. muricata, A. purpurea, and A. reticulata), Lamiaceae (Salvia amaríssima and S. polystachya), and Geraniaceae (Geranium niveum and G. mexicanum). Extracts were analyzed in terms of hydroxyl radical (OHâ¢), peroxyl radical (ROOâ¢), and superoxide anion (O2â¢-). The efficiency of the extracts to prevent neuronal death induced by excitotoxicity was tested with the tetrazolium assay, the O2â¢- scavenging capacity was evaluated with the dihydroethidium dye, and the protective effect of the extracts with the highest antioxidant activity was tested on a stroke experimental model. The extracts' IC50 values (µg/mL) of scavenging varied from 98.9 to 155.04, 4.5 to 102.4, and 20.2 to 118.97 for OHâ¢, ROOâ¢, and O2â¢-, respectively. In the excitotoxicity model, Annonaceae extracts were highly cytotoxic while Lamiaceae and Geraniaceae reduced intracellular O2â¢- production and protect neurons against oxidative stress. Salvia polystachya reduced cerebral damage, as well as improved survival and behavior after ischemia. Our results encouraged the use of plant extracts as natural antioxidants to minimize neuronal injury following stroke.
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Stroke is a public health problem due to its high mortality and disability rates; despite these, the pharmacological treatments are limited. Oxidative stress plays an important role in cerebral damage in stroke and the activation of the nuclear factor erythroid 2-related factor 2 (Nrf2) confers protection against oxidative stress. Different compounds, such as diallyl trisulfide (DATS), have the ability to activate Nrf2. DATS protects against the damage induced in oxygen-glucose deprivation in neuronal cells; however, in in vivo models of cerebral ischemia, DATS has not been evaluated. Male Wistar rats were subjected to 1 h of ischemia and seven days of reperfusion and the protective effect of DATS was evaluated. DATS administration (IR + DATS) decreased the infarct area and brain damage in the striatum and cortex; improved neurological function; decreased malondialdehyde and metalloproteinase-9 levels; increased Nrf2 activation in the cortex and the expression of superoxide dismutase 1 (SOD1) in the nucleus, SOD2 and glutathione S-transferase (GST) in the striatum and cortex; and increased the activity of catalase (CAT) in the striatum and glutathione peroxidase (GPx) in the cortex. Our results demonstrate the protective effect of DATS in an in vivo model of cerebral ischemia that involves Nrf2 activation.
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Abstract Cerebrovascular disease involve the alterations caused by pathology process of the sanguineous vessels, affecting one or many brain areas. Cerebrovascular disease is also known like stroke or ictus; it is the third cause of death around the world and is the neurologic pathology with the most prevalence rate. Cerebrovascular disease induces several changes in genetic expression inside the neurovascular unit (glia cells, neurons and ependymal cells); principally, changes in the oxidative stress and calcium inflow into the cells, this could start cellular death and tissue destruction, causing an irreversible injury in brain, losing several functions. The injury causes the activation of signaling pathways to respond to the stress, where many molecules such as proteins and mRNA are involved to act as intermediaries to activate or deactivate stress mechanisms; these molecules are able to transmit extracellular signals into the nucleus activating early gene expression like proto-oncogenes and several transcription factors to repair the cerebral injury. It is important to know the relation of the changes in genetic expression and proteins to avoid the development of injury and to activate the brain recovery. This knowledge let us diagnose the injury rate and propose therapeutic mechanisms to reduce or avoid the adverse effects on time, before the cellular death start.
Resumen Las enfermedades cerebrovasculars implican las alteraciones causadas por el proceso patológico de los vasos sanguíneos, que afectan a una o varias áreas del cerebro. La enfermedad cerebro-vascular también se conoce como ictus o ictus; Es la tercera causa de muerte en todo el mundo y es la patología neurológica con mayor tasa de prevalencia. La enfermedad cerebrovascular induce varios cambios en la expresión genética dentro de la unidad neurovascular (células gliales, neuronas y células ependimales); Principalmente, los cambios en el estrés oxidativo y la entrada de calcio en las células, podrían iniciar la muerte celular y la destrucción del tejido, causando una lesión irreversible en el cerebro, perdiendo varias funciones. La lesión hace que la activación de las vías de señalización responda al estrés, donde muchas moléculas, como las proteínas y el ARNm, actúan como intermediarios para activar o desactivar los mecanismos de estrés; estas moléculas son capaces de transmitir señales extracelulares en el núcleo activando la expresión génica temprana como protooncogenes y varios factores de transcripción para reparar la lesión cerebral. Es importante conocer la relación de los cambios en la expresión genética y las proteínas para evitar el desarrollo de lesiones y activar la recuperación del cerebro. Este conocimiento nos permite diagnosticar la tasa de lesiones y proponer mecanismos terapéuticos para reducir o evitar los efectos adversos a tiempo, antes de que comience la muerte celular.
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Molecules exhibiting antioxidant, neuroprotective, and regulatory properties inherent to natural products consumed by humans are gaining attention in biomedical research. Ferulic acid (FA) is a phenolic compound possessing antioxidant and cytoprotective properties. It is found in several vegetables, including sugarcane, where it serves as the main antioxidant component. Here, we compared the antioxidant and cytoprotective effects of FA with those of the total sugarcane aqueous extract (SCAE). Specifically, we assessed biochemical markers of cell dysfunction in rat cortical brain slices and markers of physiological stress in Caenorhabditis elegans upon exposure to toxins evoking different mechanisms of neurotoxicity, including direct oxidative stress and/or excitotoxicity. In rat cortical slices, FA (250 and 500 µM), but not SCAE (~ 270 µM of total polyphenols), prevented the loss of reductive capacity induced by the excitotoxin quinolinic acid (QUIN, 100 µM), the pro-oxidant agent ferrous sulfate (FeSO4, 25 µM), and the dopaminergic pro-oxidant 6-hydroxydopamine (6-OHDA, 100 µM). In wild-type (N2) C. elegans, FA (38 mM) exerted protective effects on decreased survival induced by FeSO4 (15 mM) and 6-OHDA (25 mM), and the motor alterations induced by QUIN (100 mM), FeSO4, and 6-OHDA. In contrast, SCAE (~ 13.5 mM of total polyphenols) evoked protective effects on the decreased survival induced by the three toxic agents, the motor alterations induced by FeSO4, and the reproductive deficit induced by FeSO4. In addition, FA was unable to reverse the decreased survival induced by all these toxins in the skn-1-/- strain (VC1772), which lacks the homolog of mammalian Nrf2, a master antioxidant gene. Altogether, our results suggest that (1) both FA and SCAE afford protection against toxic conditions, (2) not all the effects inherent to SCAE are due to FA, and (3) FA requires the skn-1 pathway to exert its protective effects in C. elegans.
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Ácidos Cumáricos/uso terapêutico , Síndromes Neurotóxicas/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Saccharum/química , Análise de Variância , Animais , Animais Geneticamente Modificados , Coeficiente de Natalidade , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Modelos Animais de Doenças , Compostos Ferrosos/toxicidade , Técnicas In Vitro , Ferro/metabolismo , Locomoção/efeitos dos fármacos , Masculino , Síndromes Neurotóxicas/etiologia , Síndromes Neurotóxicas/fisiopatologia , Oxidopamina/toxicidade , Extratos Vegetais/química , Ácido Quinolínico/toxicidade , Ratos , Ratos WistarRESUMO
OBJECTIVE: Pituitary adenomas can be classified as clinically functional or silent. Depending on the reviewed literature, these are the first or second place in frequency of the total pituitary adenomas. Even rarer is the presence of a functional gonadotropinoma since only very few case reports exist to date. The conversion of a clinically silent to functional pituitary adenoma is extraordinarily rare; the mechanisms that explain these phenomena are unknown or not fully understood. METHODS: We report the case of a woman who initially had a nonfunctional gonadotropinoma and in the course of her medical condition showed biochemical changes in her hormonal pituitary profile compatible with a functional gonadotropinoma. RESULTS: We considered that the patient had a functional gonadotropinoma due to the hyperestrogenemia in the context of secondary amenorrhea, resolving the hyperestrogenemia after almost complete resection of the tumor. CONCLUSION: It is necessary to point out from a clinical and/or biochemical point of view the change in functionality that a nonfunctional pituitary adenoma may have. In the case of our patient, the suspicion of this change in functionality became evident when we found an increase in the FSH/LH ratio and a progressive increase in serum estradiol concentrations when the patient had amenorrhea.
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The tryptophan metabolite, quinolinic acid (QUIN), and the mitochondrial toxin 3-nitropropionic acid (3-NP) are two important tools for toxicological research commonly used in neurotoxic models of excitotoxicity, oxidative stress, energy depletion, and neuronal cell death in mammals. However, their toxic properties have yet to be explored in the nematode Caenorhabditis elegans (C. elegans) for the establishment of novel, simpler, complementary, alternative, and predictive neurotoxic model of mammalian neurotoxicity. In this work, the effects of QUIN (1-100 mM) and 3-NP (1-10 mM) were evaluated on various physiological parameters (survival, locomotion, and longevity) in a wild-type (WT) strand of C. elegans (N2). Their effects were also tested in the VC1772 strain (knock out for the antioxidant SKN-1 pathway) and the VP596 strain (worms with a reporter gene for glutathione S-transferase (GST) transcription) in order to establish the role of the SKN-1 pathway in the mode of action of QUIN and 3-NP. In N2, the higher doses of both toxins decreased survival, though only QUIN altered motor activity. Both toxins also reduced longevity in the VC1772 strain (as compared to N2 strain) and augmented GST transcription in the VP596 strain at the highest doses. The changes induced by both toxins require high doses, and therefore appear moderate when compared with other toxic agents. Nevertheless, the alterations produced by QUIN and 3-NP in C. elegans are relevant to mammalian neurotoxicity as they provide novel mechanistic approaches to the assessment of neurotoxic events comprising oxidative stress and excitotoxicity, in the nematode model.
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Anti-Hipertensivos/toxicidade , Proteínas de Caenorhabditis elegans/efeitos dos fármacos , Proteínas de Ligação a DNA/efeitos dos fármacos , Nitrocompostos/toxicidade , Propionatos/toxicidade , Ácido Quinolínico/toxicidade , Fatores de Transcrição/efeitos dos fármacos , Animais , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/metabolismo , Corpo Estriado/efeitos dos fármacos , Modelos Animais de Doenças , Mitocôndrias/efeitos dos fármacos , Síndromes Neurotóxicas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fatores de Transcrição/metabolismoRESUMO
"Lipomatous" and "extensively vacuolated" are descriptive captions that have been used to portray a curious subset of ependymomas distinctively bearing cells with a large vacuole pushing the nucleus to the periphery and, thus, simulating a signet-ring cell appearance. Here, we would like to report the first ependymoma of this kind in a Latin American institution. A 16-year-old boy experienced cephalea during three months. Magnetic resonance imaging scans showed a left paraventricular tumour which corresponded to anaplastic ependymoma. Intriguingly, it was also composed of cells with single or multiple hollow cytoplasmic vacuoles sometimes giving a signet-ring cell-like configuration. Immunolabeling of these showed membrane positivity for GFAP, PS100, and CD99, while Ki-67 expression was null. Ultrastructural examination of retrieved paraffin-embedded tissue showed the presence of scarce microlumina filled with microvilli but failed to demonstrate any content in such optically empty vacuoles as only scant granulofibrillary debris was observed. A schism prevails at present regarding these unusual morphological variants, being either "lipomatous" or "vacuolated" based mainly on the EMA immunoprofile. This, however, is a misappropriate approaching. Could it be that perhaps we are dealing with the same histopathological entity or it may simply happen that fixation and artefacts cannot allow for their proper identification?
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Cytoskeletal organization, actin-myosin contractility and the cell membrane together regulate cell morphology in response to the cell environment, wherein the extracellular matrix (ECM) is an indispensable component. Plasticity in cell shape enables cells to adapt their migration mode to their surroundings. GH3 endocrine cells respond to different ECM proteins, acquiring different morphologies: a rounded on collagen I-III (C I-III) and an elongated on collagen IV (C IV). However, the identities of the molecules that participate in these responses remain unknown. Considering that actin-myosin contractility is crucial to maintaining cell shape, we analyzed the participation of MLCK and ROCK in the acquisition of cell shape, the generation of cellular tension and the cell motility mode. We found that a rounded shape with high cortical tension depends on MLCK and ROCK, whereas in cells with an elongated shape, MLCK is the primary protein responsible for cell spreading. Further, in cells with a slow and directionally persistent motility, MLCK predominates, while rapid and erratic movement is ROCK-dependent. This behavior also correlates with GTPase activation. Cells on C I-III exhibited higher Rho-GTPase activity than cells on C IV and vice versa with Rac-GTPase activity, showing a plastic response of GH3 cells to their environment, leading to the generation of different cytoskeleton and membrane organizations and resulting in two movement strategies, rounded and fibroblastoid-like.
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Adesão Celular/genética , Movimento Celular/genética , Contração Muscular/genética , Peptídeos/genética , Quinases Associadas a rho/genética , Citoesqueleto de Actina/genética , Citoesqueleto de Actina/metabolismo , Actinas/genética , Actinas/metabolismo , Animais , Membrana Celular/genética , Membrana Celular/metabolismo , Forma Celular/genética , Matriz Extracelular/genética , Contração Muscular/fisiologia , Peptídeos/metabolismo , Fosforilação , Ratos , Transdução de Sinais/genética , Quinases Associadas a rho/biossínteseRESUMO
Stroke is a frequent cause of death and the first of disability in the world population. We have shown that dapsone acts as an antioxidant, antiinflammatory and antiapoptotic agent after brain Ischemia reperfusion (I/R) in rats; however, its therapeutic efficacy, measured by imaging has not been characterized. In this context, the aim of this study was to evaluate the neuroprotective effect of dapsone by magnetic resonance imaging (MRI) and to correlate imaging markers with motor function and oxidative stress after transient cerebral ischemia and reperfusion (I/R). We used male rats throughout the experiment. Functional deficit after I/R was assessed by using Longa scale. The area of brain tissue damage was measured by histology. The nuclear factor erythroid 2-related factor 2 (Nrf-2) and the amount of reactive oxygen species (ROS) were measured as biomarkers of oxidative stress. Finally, difussion tensor MRI was employed to measure the fractional anisotropy (FA), as a MRI marker of the pathophysiologic brain status. Results showed a better functional recovery and less damaged tissue in animals treated with dapsone vs control group. The values of FA were higher in animals receiving treatment, indicating a better preservation of brain structure. At early stages of the damage, dapsone was able to reduce both oxidative markers (Nrf-2 and ROS). Our findings provide new evidence for the efficacy of dapsone when administered during the acute phase after I/R and that quantitative sequences of MRI are useful for characterizing its potential therapeutic benefits after stroke.
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Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/tratamento farmacológico , Dapsona/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Traumatismo por Reperfusão/diagnóstico por imagem , Traumatismo por Reperfusão/tratamento farmacológico , Acidente Vascular Cerebral/complicações , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Isquemia Encefálica/complicações , Isquemia Encefálica/patologia , Imageamento por Ressonância Magnética , Masculino , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/patologiaRESUMO
Thalidomide has shown protective effects in different models of ischemia/reperfusion damage. To elucidate the mechanisms of such protection, this study assessed the effects of thalidomide on the oxidative stress and inflammatory response induced by ischemia/reperfusion episodes in rats. Rats underwent middle cerebral artery occlusion (MCAO) for 2hours. All animals were sacrificed after different reperfusion times. Rats were administered either DMSO or thalidomide (20mg/kg (i.p.)) at different times before or during reperfusion: 1) 1h before reperfusion; the infarct area was measured 2h after reperfusion. 2) 10min before reperfusion and 80min after reperfusion; the infarct area was measured 24h after reperfusion; and 3) 10min before reperfusion and 1h, 24h, 48h, and 68h after reperfusion; the infarct area was measured 72h after reperfusion. Thalidomide reduced the infarct area 24h and 72h after MCAO, and decreased the neurological deficit in all groups with respect to controls. Thalidomide also lowered significantly the number of TUNEL-positive cells, levels of Bax, caspase-3, lipoperoxidation, and pro-inflammatory cytokines, and increased the levels of SOD1, Bcl-2 and pAkt. These results show that thalidomide has neuroprotective effects, apparently due to its anti-apoptotic, anti-oxidant, and anti-inflammatory effects.
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Inibidores da Angiogênese/farmacologia , Isquemia Encefálica/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Talidomida/farmacologia , Animais , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Inflamação/tratamento farmacológico , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos WistarRESUMO
BACKGROUND: Hyperprolactinemia is a common finding within clinical practice in both endocrinology and general practice fields, amongst other specialties. The general practitioner and other specialists must know the indications and serum prolactin determination parameters in order to, once detected, derive the patient for a correct assessment and begin treatment. OBJECTIVE: Formulate a clinical practice guideline evidence-based for the diagnosis and treatment of hyperprolactinemia. METHOD: It took the participation of eight gynecologists, two pathologists and a pharmacologist in the elaboration of this guideline due their experience and clinical judgement. These recommendations were based upon diagnostic criteria and levels of evidence from treatment guidelines previously established, controlled clinical trials and standardized guides for adolescent and adult population with hyperprolactinemia. RESULTS: During the conformation of this guideline each specialist reviewed and updated a specific topic and established the evidence existent over different topics according their field of best clinical expertise, being enriched by the opinion of other experts. At the end, all the evidence and decisions taken were unified in the document presented here. CONCLUSIONS: It is presented the recommendations established by the panel of experts for diagnosis and treatment of patients with high levels of prolactin; also the level of evidence for the diagnosis of hyperprolactinemia, handling drug-induced hyperprolactinemia and prolactinomas in pregnant and non-pregnant patients.
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Hiperprolactinemia/terapia , Guias de Prática Clínica como Assunto , Prolactinoma/terapia , Adolescente , Adulto , Medicina Baseada em Evidências , Feminino , Humanos , Hiperprolactinemia/diagnóstico , Hiperprolactinemia/fisiopatologia , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/terapia , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/fisiopatologia , Complicações na Gravidez/terapia , Prolactina/metabolismo , Prolactinoma/diagnóstico , Prolactinoma/patologiaRESUMO
After transient cerebral ischemia and reperfusion (I/R), damaging mechanisms, such as excitotoxicity and oxidative stress, lead to irreversible neurological deficits. The induction of metallothionein-II (MT-II) protein is an endogenous mechanism after I/R. Our aim was to evaluate the neuroprotective effect of MT-II after I/R in rats. Male Wistar rats were transiently occluded at the middle cerebral artery for 2 h, followed by reperfusion. Rats received either MT (10 µg per rat i.p.) or vehicle after ischemia. Lipid peroxidation (LP) was measured 22 h after reperfusion in frontal cortex and hippocampus; also, neurological deficit was evaluated after ischemia, using the Longa scoring scale. Infarction area was analyzed 72 hours after ischemia. Results showed increased LP in frontal cortex (30.7%) and hippocampus (26.4%), as compared to control group; this effect was fully reversed by MT treatment. Likewise, we also observed a diminished neurological deficit assessed by the Longa scale in those animals treated with MT compared to control group values. The MT-treated group showed a significant (P < 0.05) reduction of 39.9% in the infarction area, only at the level of hippocampus, as compared to control group. Results suggest that MT-II may be a novel neuroprotective treatment to prevent ischemia injury.
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Ataque Isquêmico Transitório/tratamento farmacológico , Ataque Isquêmico Transitório/fisiopatologia , Peroxidação de Lipídeos/efeitos dos fármacos , Metalotioneína/uso terapêutico , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/fisiopatologia , Animais , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/patologia , Lobo Frontal/fisiopatologia , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Hipocampo/fisiopatologia , Ataque Isquêmico Transitório/complicações , Ataque Isquêmico Transitório/patologia , Masculino , Metalotioneína/administração & dosagem , Metalotioneína/farmacologia , Coelhos , Ratos , Ratos Wistar , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/patologiaRESUMO
In humans, exposure to organic solvents (OS) is frequent in work activities or as a recreational inhalant, inducing severe neuropathy (secondary to demyelization of peripheral nerves). We have previously shown that all-trans retinoic acid (ATRA) increases local content of neural growth factor (NGF), improving peripheral neuropathy of diverse origins. In this study, we evaluated the effect of ATRA on OS-induced peripheral neuropathy in experimental mice. Two simultaneous experiments were performed. The first one aimed to evaluate ATRA for the prevention of damage induced by OS, the second to test ATRA as an OS-induced neuropathy treatment. Nociceptive threshold latency and NGF concentration in serum and in peripheral nerves were determined. Morphological changes and evidence of sciatic nerve regeneration were evaluated. Mice exposed to OS developed neuropathy and axonal degeneration. ATRA diminished the effects of OS inhalation on sensorial changes and nerve morphology. Treatment with ATRA reversed sensorial and nerve morphological changes of OS-induced neuropathy, and this was associated with increased contents of NGF. Similar to previous experiences on diabetic and toxic neuropathy, ATRA reduced and partially reversed the peripheral neuropathy caused by OS exposure. These favorable effects apparently are due to local production of NGF induced by neural regeneration in response to the administration of retinoic acid.
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Regeneração Nervosa/efeitos dos fármacos , Limiar da Dor/efeitos dos fármacos , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Tretinoína/uso terapêutico , Animais , Camundongos , Fator de Crescimento Neural/sangue , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/metabolismo , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/lesões , Nervo Isquiático/metabolismo , Solventes , Tretinoína/farmacologiaRESUMO
Craniopharyngiomas (CPs) are benign epithelial cystic tumors of the sellar and suprasellar region with a high survival rate and high recurrence in children. CPs contain dense oily fluid, but little is known yet about this content and its contribution to tissue damage and tumoral growth. In this study, we developed a simple experimental model produced by intracortical injection to rats of the cyst fluid content collected from human CPs to explore its possible contribution to brain tissue damage. The cyst fluid of the CPs ("oil machinery fluid") was collected during surgical removal, briefly preserved and further tested in rats through intracortical infusion. The group receiving "oil machinery fluid" presented increased reactive oxygen species formation, oxidative damage to lipids and reactive gliosis accompanied by augmented immunoreactivity to peroxiredoxin and thioredoxin reductase 1 at 15, 30 and 45 days post-injection. Other markers of inflammation and cell damage were stimulated at all post-lesion days tested. There was also a body weight gain. The persistence of tissue damage and oxidative stress suggests that "oil machinery fluid" exerts progressive alterations similar to those observed in patients with CPs, supporting the concept that some components of cyst fluid may contribute to brain tissue damage in these patients.
Assuntos
Craniofaringioma/metabolismo , Neoplasias Hipofisárias/metabolismo , Adolescente , Adulto , Animais , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Craniofaringioma/patologia , Feminino , Gliose/metabolismo , Humanos , Peroxidação de Lipídeos , Masculino , Pessoa de Meia-Idade , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo , Peroxirredoxinas/metabolismo , Neoplasias Hipofisárias/patologia , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Tiorredoxina Redutase 1/metabolismo , Extratos de Tecidos/fisiologia , Fator de Necrose Tumoral alfa/metabolismo , Aumento de Peso , Adulto JovemRESUMO
Antioxidant properties and protective effect of aged garlic extract (AGE) and of 20% hydroethanolic fresh extracts from garlic clove (GCE) and skin (GSE) on cerebral ischemia were evaluated by administering extracts at the beginning of reperfusion in a rat model of stroke. All three extracts scavenged superoxide anion, peroxynitrite anion, and peroxyl radicals, but with different efficiencies; furthermore, GCE and GSE scavenged hydroxyl radicals and GSE scavenged singlet oxygen. These extracts significantly prevented reduction of neuronal nuclear antigen in the infarcted area, although no improvement in neurological function was observed. Importantly, GCE and GSE contained S-allylcystein, a compound associated with AGE's neuroprotective effect against damage induced by cerebral ischemia. Extracts decreased mRNA expression of NR1- and NR2B-NMDA-receptor subunits and prevented ischemia-induced reduction in mitochondrial potential and in ATP synthesis. These results indicate that antioxidants present in garlic extracts may regulate ROS concentrations during ischemia, favour pro-survival pathways, and attenuate mitochondrial dysfunction.