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1.
Arterioscler Thromb Vasc Biol ; 39(11): 2386-2401, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31644355

RESUMO

OBJECTIVE: The male-specific region of the Y chromosome (MSY) remains one of the most unexplored regions of the genome. We sought to examine how the genetic variants of the MSY influence male susceptibility to coronary artery disease (CAD) and atherosclerosis. Approach and Results: Analysis of 129 133 men from UK Biobank revealed that only one of 7 common MSY haplogroups (haplogroup I1) was associated with CAD-carriers of haplogroup I1 had ≈11% increase in risk of CAD when compared with all other haplogroups combined (odds ratio, 1.11; 95% CI, 1.04-1.18; P=6.8×10-4). Targeted MSY sequencing uncovered 235 variants exclusive to this haplogroup. The haplogroup I1-specific variants showed 2.45- and 1.56-fold respective enrichment for promoter and enhancer chromatin states, in cells/tissues relevant to atherosclerosis, when compared with other MSY variants. Gene set enrichment analysis in CAD-relevant tissues showed that haplogroup I1 was associated with changes in pathways responsible for early and late stages of atherosclerosis development including defence against pathogens, immunity, oxidative phosphorylation, mitochondrial respiration, lipids, coagulation, and extracellular matrix remodeling. UTY was the only Y chromosome gene whose blood expression was associated with haplogroup I1. Experimental reduction of UTY expression in macrophages led to changes in expression of 59 pathways (28 of which overlapped with those associated with haplogroup I1) and a significant reduction in the immune costimulatory signal. CONCLUSIONS: Haplogroup I1 is enriched for regulatory chromatin variants in numerous cells of relevance to CAD and increases cardiovascular risk through proatherosclerotic reprogramming of the transcriptome, partly through UTY.


Assuntos
Cromossomos Humanos Y , Doença da Artéria Coronariana/genética , Pleiotropia Genética , Predisposição Genética para Doença , Expressão Gênica , Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Macrófagos/metabolismo , Masculino , Antígenos de Histocompatibilidade Menor/genética , Proteínas Nucleares/genética , Filogenia , Fatores de Risco , Células THP-1
2.
Allergy ; 73(6): 1151-1181, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29105786

RESUMO

To address uncertainties in the prevention and management of influenza in people with asthma, we performed a scoping review of the published literature on influenza burden; current vaccine recommendations; vaccination coverage; immunogenicity, efficacy, effectiveness, and safety of influenza vaccines; and the benefits of antiviral drugs in people with asthma. We found significant variation in the reported rates of influenza detection in individuals with acute asthma exacerbations making it unclear to what degree influenza causes exacerbations of underlying asthma. The strongest evidence of an association was seen in studies of children. Countries in the European Union currently recommend influenza vaccination of adults with asthma; however, coverage varied between regions. Coverage was lower among children with asthma. Limited data suggest that good seroprotection and seroconversion can be achieved in both children and adults with asthma and that vaccination confers a degree of protection against influenza illness and asthma-related morbidity to children with asthma. There were insufficient data to determine efficacy in adults. Overall, influenza vaccines appeared to be safe for people with asthma. We identify knowledge gaps and make recommendations on future research needs in relation to influenza in patients with asthma.


Assuntos
Asma/complicações , Asma/epidemiologia , Influenza Humana/complicações , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Antivirais/uso terapêutico , Efeitos Psicossociais da Doença , Saúde Global , Humanos , Imunogenicidade da Vacina , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/imunologia , Influenza Humana/terapia , Avaliação de Resultados da Assistência ao Paciente , Vigilância em Saúde Pública , Resultado do Tratamento , Vacinação
3.
Allergy ; 72(12): 1825-1848, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28543086

RESUMO

BACKGROUND: To inform the development of the European Academy of Allergy and Clinical Immunology's (EAACI) Guidelines on Allergen Immunotherapy (AIT) for allergic asthma, we assessed the evidence on the effectiveness, cost-effectiveness and safety of AIT. METHODS: We performed a systematic review, which involved searching nine databases. Studies were screened against predefined eligibility criteria and critically appraised using established instruments. Data were synthesized using random-effects meta-analyses. RESULTS: 98 studies satisfied the inclusion criteria. Short-term symptom scores were reduced with a standardized mean difference (SMD) of -1.11 (95% CI -1.66, -0.56). This was robust to a prespecified sensitivity analyses, but there was evidence suggestive of publication bias. Short-term medication scores were reduced SMD -1.21 (95% CI -1.87, -0.54), again with evidence of potential publication bias. There was no reduction in short-term combined medication and symptom scores SMD 0.17 (95% CI -0.23, 0.58), but one study showed a beneficial long-term effect. For secondary outcomes, subcutaneous immunotherapy (SCIT) improved quality of life and decreased allergen-specific airway hyperreactivity (AHR), but this was not the case for sublingual immunotherapy (SLIT). There were no consistent effects on asthma control, exacerbations, lung function, and nonspecific AHR. AIT resulted in a modest increased risk of adverse events (AEs). Although relatively uncommon, systemic AEs were more frequent with SCIT; however no fatalities were reported. The limited evidence on cost-effectiveness was mainly available for sublingual immunotherapy (SLIT) and this suggested that SLIT is likely to be cost-effective. CONCLUSIONS: AIT can achieve substantial reductions in short-term symptom and medication scores in allergic asthma. It was however associated with a modest increased risk of systemic and local AEs. More data are needed in relation to secondary outcomes, longer-term effectiveness and cost-effectiveness.


Assuntos
Alérgenos/imunologia , Asma/imunologia , Asma/terapia , Dessensibilização Imunológica , Asma/diagnóstico , Análise Custo-Benefício , Dessensibilização Imunológica/efeitos adversos , Dessensibilização Imunológica/métodos , Humanos , Injeções Subcutâneas , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Testes de Função Respiratória , Imunoterapia Sublingual , Avaliação de Sintomas , Fatores de Tempo , Resultado do Tratamento
4.
Cell Mol Life Sci ; 69(5): 741-62, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21997383

RESUMO

The metabolic syndrome is a cluster of common pathologies: abdominal obesity linked to an excess of visceral fat, insulin resistance, dyslipidemia and hypertension. At the molecular level, metabolic syndrome is accompanied not only by dysregulation in the expression of adipokines (cytokines and chemokines), but also by alterations in levels of leptin, a peptide hormone released by white adipose tissue. These changes modulate immune response and inflammation that lead to alterations in the hypothalamic 'bodyweight/appetite/satiety set point,' resulting in the initiation and development of metabolic syndrome. Metabolic syndrome is a risk factor for neurological disorders such as stroke, depression and Alzheimer's disease. The molecular mechanism underlying the mirror relationship between metabolic syndrome and neurological disorders is not fully understood. However, it is becoming increasingly evident that all cellular and biochemical alterations observed in metabolic syndrome like impairment of endothelial cell function, abnormality in essential fatty acid metabolism and alterations in lipid mediators along with abnormal insulin/leptin signaling may represent a pathological bridge between metabolic syndrome and neurological disorders such as stroke, Alzheimer's disease and depression. The purpose of this review is not only to describe the involvement of brain in the pathogenesis of metabolic syndrome, but also to link the pathogenesis of metabolic syndrome with neurochemical changes in stroke, Alzheimer's disease and depression to a wider audience of neuroscientists with the hope that this discussion will initiate more studies on the relationship between metabolic syndrome and neurological disorders.


Assuntos
Síndrome Metabólica/complicações , Síndrome Metabólica/patologia , Doenças do Sistema Nervoso/etiologia , Adipocinas/metabolismo , Moduladores de Receptores de Canabinoides/metabolismo , Ceramidas/metabolismo , Humanos , Insulina/metabolismo , Resistência à Insulina , Leptina/metabolismo , Metabolismo dos Lipídeos , Fatores de Risco
5.
Biomedicines ; 11(4)2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37189799

RESUMO

Although there is increasing evidence that oxidative stress and inflammation induced by COVID-19 may contribute to increased risk and severity of thromboses, the underlying mechanism(s) remain to be understood. The purpose of this review is to highlight the role of blood lipids in association with thrombosis events observed in COVID-19 patients. Among different types of phospholipases A2 that target cell membrane phospholipids, there is increasing focus on the inflammatory secretory phospholipase A2 IIA (sPLA2-IIA), which is associated with the severity of COVID-19. Analysis indicates increased sPLA2-IIA levels together with eicosanoids in the sera of COVID patients. sPLA2 could metabolise phospholipids in platelets, erythrocytes, and endothelial cells to produce arachidonic acid (ARA) and lysophospholipids. Arachidonic acid in platelets is metabolised to prostaglandin H2 and thromboxane A2, known for their pro-coagulation and vasoconstrictive properties. Lysophospholipids, such as lysophosphatidylcholine, could be metabolised by autotaxin (ATX) and further converted to lysophosphatidic acid (LPA). Increased ATX has been found in the serum of patients with COVID-19, and LPA has recently been found to induce NETosis, a clotting mechanism triggered by the release of extracellular fibres from neutrophils and a key feature of the COVID-19 hypercoagulable state. PLA2 could also catalyse the formation of platelet activating factor (PAF) from membrane ether phospholipids. Many of the above lipid mediators are increased in the blood of patients with COVID-19. Together, findings from analyses of blood lipids in COVID-19 patients suggest an important role for metabolites of sPLA2-IIA in COVID-19-associated coagulopathy (CAC).

6.
Neurosignals ; 20(2): 72-85, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22025073

RESUMO

Secretory phospholipase A(2) (sPLA(2)) isoforms are widely expressed in the brain and spinal cord. Group IIA sPLA(2) (sPLA(2)-IIA) has been shown to stimulate exocytosis and release of neurotransmitters in neuroendocrine PC12 cells and neurons, suggesting a role of the enzyme in neuronal signaling and synaptic transmission. However, the mechanisms by which sPLA(2) is itself released, and a possible relation between glutamate receptors and sPLA(2) exocytosis, are unknown. This study was carried out to elucidate the effects of glutamate receptor agonists on exocytosis of sPLA(2)-IIA in transfected SH-SY5Y neuroblastoma cells. sPLA(2)-IIA enzyme was packaged in fusion-competent vesicles and released constitutively or upon stimulation, suggesting regulated secretion. The signal peptide of sPLA(2)-IIA is required for its vesicular localization and exocytosis. External application of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and kainate (KA) induced vesicular exocytosis and release of sPLA(2)-IIA. UBP 302, a GluR5-specific KA receptor antagonist, abolished the effect of KA, confirming the role of KA receptors in mediating sPLA(2)-IIA secretion. Moreover, KA-induced sPLA(2)-IIA secretion is dependent on Ca(2+) and protein kinase C. Together, these findings provide evidence of a link between glutamate receptors and regulated sPLA(2) secretion in neurons that may play an important role in synaptic plasticity, pain transmission and neurodegenerative diseases.


Assuntos
Exocitose/fisiologia , Fosfolipases A2 do Grupo II/metabolismo , Receptores de Ácido Caínico/fisiologia , Animais , Linhagem Celular Tumoral , Células Cultivadas , Agonistas de Aminoácidos Excitatórios/farmacologia , Exocitose/efeitos dos fármacos , Fosfolipases A2 do Grupo II/efeitos dos fármacos , Humanos , Ácido Caínico/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ratos , Receptores de Ácido Caínico/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/farmacologia
7.
Biochim Biophys Acta ; 1801(8): 906-16, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20170745

RESUMO

Degradation of glycerophospholipids, sphingolipids and cholesterol in the nucleus modulates neural cell proliferation and differentiation, inflammation, apoptosis, migration, cell adhesion, and intracellular trafficking. Extracellular signals from agonists (neurotransmitters, cytokines, and growth factors) regulate the activity of a key set of lipid-metabolizing enzymes, such as phospholipases, sphingomyelinases, and cholesterol hydroxylases. These enzymes and their downstream targets constitute a complex lipid signaling network with multiple nodes of interaction and cross-regulation through their lipid mediators, which include eicosanoids, docosanoids, diacylglycerols, platelet activating factor, lysophosphatidic acid, ceramide and ceramide 1-phosphate, sphingosine and sphingosine 1-phosphate, and hydroxycholesterols. Receptors for above lipid mediators are localized at the neural cell nucleus. Stimulation of isolated nuclei with these lipids and agonists results in changes in transcriptional regulation of major genes, including c-fos, cylooxygenase-2, secretory phospholipase A(2) and endothelial as well as inducible nitric oxide synthases. Imbalances in signaling network involving above genes may contribute to the pathogenesis of human neurological disorders. In this review, we have attempted to integrate available information on above lipid mediators in the nucleus. In addition, attempts have been made to explain cross-talk among glycerophospholipid-, sphingolipid-, and cholesterol-derived lipid mediators in neural cell death in Alzheimer's disease.


Assuntos
Doença de Alzheimer/etiologia , Núcleo Celular/metabolismo , Metabolismo dos Lipídeos/fisiologia , Lipídeos/fisiologia , Doença de Alzheimer/metabolismo , Animais , Membrana Celular/enzimologia , Membrana Celular/metabolismo , Membrana Celular/fisiologia , Núcleo Celular/enzimologia , Núcleo Celular/fisiologia , Humanos , Redes e Vias Metabólicas/fisiologia , Modelos Biológicos
8.
Neurochem Res ; 36(2): 347-54, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21116712

RESUMO

This study was carried out to elucidate the effects of calcium independent phospholipase A(2) (iPLA(2)) on mitochondrial function and exocytosis in neuroendocrine cells. iPLA(2) mRNA and protein were detected in cell lysates and mitochondria from PC12 cells. Treatment of cells with the iPLA(2) inhibitor, bromoenol lactone (BEL), resulted in reduction in the mitochondrial membrane potential. Increase in membrane capacitance and number of spikes at amperometry, indicating exocytosis, were detected from PC12 cells after treatment with BEL. The induced exocytosis was abolished by pre-incubation of cells with the antioxidant, glutathione monoethyl ester, spin-trap/free radical scavenger, PBN, or inhibitors of the mitochondrial permeability transition pore, cyclosporine A and bongkrekic acid. These findings indicate that inhibition of iPLA(2) results in excessive exocytosis through increased oxidative damage (or failure to repair such damage) and defects in mitochondrial function. A similar process may occur in neurons with mutations in iPLA(2), leading to neuronal injury.


Assuntos
Exocitose/fisiologia , Potencial da Membrana Mitocondrial/fisiologia , Fosfolipases A2 Independentes de Cálcio/metabolismo , Animais , Isoenzimas/genética , Isoenzimas/metabolismo , Potenciais da Membrana/fisiologia , Mitocôndrias/metabolismo , Naftalenos/metabolismo , Células PC12 , Inibidores de Fosfodiesterase/metabolismo , Fosfolipases A2 Independentes de Cálcio/antagonistas & inibidores , Fosfolipases A2 Independentes de Cálcio/genética , Pironas/metabolismo , Ratos
9.
J Neurochem ; 112(1): 34-41, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19860851

RESUMO

The present study was carried out to elucidate changes in the gene expression and activity of cholesterol biosynthetic enzymes and transporters in the rat hippocampus after kainate excitotoxicity. Significantly increased cholesterol level was detected in the degenerating hippocampus, reaching double normal levels at 1 week after kainate injury. RT-PCR analyses of hippocampal homogenates showed significantly decreased mRNA expression of the transcription factor controlling cholesterol biosynthesis SREBP-2, and the rate-controlling enzyme HMG-CoA (3-hydroxy-3-methyl-glutaryl-CoA) reductase at all time points after kainate injection; and decreased lanosterol synthase and CYP51 at 1 and 2 weeks post-kainate injection respectively. GC-MS analyses showed a significant increase in cholesterol biosynthetic precursors lanosterol, desmosterol and 7-dehydrocholesterol at 1 day after kainate injection presumably reflecting biosysnthesis in injured neurons, and significant decreases in precursors at 1 and 2 weeks post-kainate injection, at time of gliosis in the degenerating hippocampus. Levels of cholesterol autooxidation including 7 ketocholesterol and cholesterol epoxides were elevated in the kainate lesioned hippocampus. Furthermore, loss of expression of the cholesterol transporter, ABCA1 was detected in neurons, but increased expression in astrocytes was detected after kainate lesions. The results suggest that increased cholesterol biosynthesis and loss of ABCA1 expression in injured neurons might result in increase in cholesterol in the degenerating hippocampus. The increased cholesterol might predispose to increased formation of cholesterol oxidation products which have been shown to be toxic to neurons.


Assuntos
Colesterol/biossíntese , Agonistas de Aminoácidos Excitatórios/toxicidade , Transdução de Sinais/fisiologia , Transportador 1 de Cassete de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/biossíntese , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Transporte Biológico Ativo/fisiologia , Colesterol/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/patologia , Ácido Caínico/toxicidade , Masculino , Oxirredução/efeitos dos fármacos , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos
10.
J Neural Transm (Vienna) ; 117(3): 301-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20058038

RESUMO

Secretory phospholipase A2 (sPLA2) activity is present in the CNS and the sPLA2-IIA isoform has been shown to induce exocytosis in cultured hippocampal neurons. However, little is known about possible contributions of various lysophospholipid species to exocytosis in neuroendocrine cells. This study was therefore carried out to examine the effects of several lysophospholipid species on exocytosis on rat pheochromocytoma-12 (PC12) cells. An increase in vesicle fusion, indicating exocytosis, was observed in PC12 cells after external infusion of lysophosphatidylinositol (LPI), but not lysophosphatidylcholine or lysophosphatidylserine by total internal reflection microscopy. Similarly, external infusion of LPI induced significant increases in capacitance, or number of spikes detected at amperometry, indicating exocytosis. Depletion of cholesterol by pre-incubation of cells with methyl beta cyclodextrin and depletion of Ca2+ by thapsigargin and incubation in zero external Ca2+ resulted in attenuation of LPI induced exocytosis, indicating that exocytosis was dependent on the integrity of lipid rafts and intracellular Ca2+. Moreover, LPI induced a rise in intracellular Ca2+ suggesting that this could be the trigger for exocytosis. It is postulated that LPI may be an active participant in sPLA2-mediated exocytosis in the CNS.


Assuntos
Exocitose/fisiologia , Lisofosfatidilcolinas/metabolismo , Lisofosfolipídeos/metabolismo , Animais , Cálcio/metabolismo , Colesterol/metabolismo , Vesículas Citoplasmáticas/efeitos dos fármacos , Vesículas Citoplasmáticas/fisiologia , Capacitância Elétrica , Inibidores Enzimáticos/farmacologia , Exocitose/efeitos dos fármacos , Hipolipemiantes/farmacologia , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/fisiologia , Microdomínios da Membrana/efeitos dos fármacos , Microdomínios da Membrana/fisiologia , Células PC12 , Ratos , Tapsigargina/farmacologia , beta-Ciclodextrinas/farmacologia
12.
Neuroscientist ; 15(4): 392-407, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19666894

RESUMO

Lipid mediators are important endogenous regulators of neural cell proliferation, differentiation, oxidative stress, inflammation, and apoptosis. They originate from enzymic degradation of glycerophospholipids, sphingolipids, and cholesterol by phospholipases, sphingomyelinases, and cytochrome P450 hydroxylases, respectively. Arachidonic acid-derived lipid mediators are called eicosanoids. Eicosanoids have emerged as key regulators of cell proliferation, differentiation, oxidative stress, and neuroinflammation. Another arachidonic acid-derived lipid mediator is lipoxin. Eicosanoids have proinflammatory effects, whereas lipoxins produce antiinflammatory effects. The crossponding lipid mediators of docosahexaenoic acid metabolism are named docosanoids. They include resolvins, protectins, and neuroprotectins. Docosanoids produce antioxidant, anti-inflammatory, and antiapoptotic effects in the brain tissue. Other glycerophospholipid-derived lipid mediators are platelet-activating factor, lysophosphatidic acid, and endocannabinoids. Degradation of sphingolipids also results in the generation of sphingolipid-derived lipid mediators. Sphingolipid-derived lipid mediators are ceramide, ceramide 1-phosphate, sphingosine, and sphingosine 1-phosphate. They mediate cellular differentiation, cell growth, and apoptosis. Similarly, cholesterol-derived lipid mediators hydroxycholesterol and oxycholesterol produce apoptosis. Most of these mediators originate from the plasma membrane. The nucleus has its own set of enzymes and lipid mediators that originate from the nuclear envelope and matrix. The purpose of this commentary is to describe basic and clinical information on lipid mediators in the nucleus.


Assuntos
Núcleo Celular/metabolismo , Metabolismo dos Lipídeos/fisiologia , Lipídeos/fisiologia , Neurônios/metabolismo , Transdução de Sinais/fisiologia , Transporte Ativo do Núcleo Celular/fisiologia , Animais , Núcleo Celular/ultraestrutura , Eicosanoides/metabolismo , Ácidos Graxos/metabolismo , Humanos , Neurônios/ultraestrutura , Esfingolipídeos/metabolismo
13.
Int J Neuropsychopharmacol ; 12(7): 953-64, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19203412

RESUMO

Recently, there has been considerable interest in a possible link between changes in brain polyunsaturated fatty acids, neural membrane phospholipid degradation, serotonergic neurotransmission, and depression. The present study aims to examine effects of antidepressants on lipids in different regions of the brain at individual molecular species level, using the novel technique of lipidomics. Balb/C mice received daily intraperitoneal (i.p.) injections of 10 mg/kg of the antidepressants maprotiline, fluoxetine and paroxetine for 4 wk. The prefrontal cortex, hippocampus, striatum and cerebellum were harvested, and lipid profiles compared to those of saline-injected mice. Treatment with maprotiline and paroxetine, but not fluoxetine, resulted in significant decreases in phosphatidylcholine (PC) species, PC36:1, PC38:3, PC40:2p, PC40:6, PC40:5, PC42:7p, PC42:6p and PC42:5p in the prefrontal neocortex. The decreases in phospholipids were accompanied by increases in lysophospholipid species, lysoPC16:0, lysoPC18:2 and lysoPC18:0 in the prefrontal cortex, indicating increase in phospholipase A2 activity and possible release of long-chain fatty acids. Maprotiline and paroxetine treatment also resulted in decreases in sphingomyelin and increases in several ceramide species in the prefrontal cortex. It is postulated that endogenous release of long-chain fatty acids may be related to the mechanism of action of maprotiline and paroxetine.


Assuntos
Antidepressivos/farmacologia , Encéfalo/efeitos dos fármacos , Ácidos Graxos/metabolismo , Fluoxetina/farmacologia , Maprotilina/farmacologia , Paroxetina/farmacologia , Animais , Antidepressivos/administração & dosagem , Gânglios da Base/efeitos dos fármacos , Gânglios da Base/metabolismo , Encéfalo/metabolismo , Ceramidas/metabolismo , Cerebelo/efeitos dos fármacos , Cerebelo/metabolismo , Cromatografia Líquida de Alta Pressão , Fluoxetina/administração & dosagem , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Injeções Intraperitoneais , Lisofosfolipídeos/metabolismo , Masculino , Maprotilina/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Paroxetina/administração & dosagem , Fosfatidilcolinas/metabolismo , Fosfolipases A2/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Esfingomielinas/metabolismo , Fatores de Tempo
14.
Neurosci Lett ; 453(1): 6-8, 2009 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-19429004

RESUMO

High levels of calcium-independent phospholipase A(2) (iPLA(2)) are present in the striatum and cerebral cortex [W.Y. Ong, J.F. Yeo, S.F. Ling, A.A. Farooqui, Distribution of calcium-independent phospholipase A(2) (iPLA(2)) in monkey brain, J. Neurocytol. 34 (2005) 447-458], and several clinical investigations have suggested a possible role of altered iPLA(2) activity in neurodegenerative and psychiatric disorders. The present study was carried out to elucidate a possible effect of PLA(2) on prepulse inhibition (PPI) of the acoustic startle reflex. Rats that received intraperitoneal injection of the non-specific PLA(2) inhibitor, quinacrine, showed significantly decreased PPI at 76, 80, and 84dB, compared to saline injected controls. In addition, rats that received intrastriatal injection of antisense oligonucleotide to iPLA(2) showed significant reduction in PPI at prepulse intensities of 76 and 84dB compared to scrambled sense injected controls. Together, these findings point to a role of PLA(2) in PPI of the auditory startle reflex and sensorimotor gating.


Assuntos
Fosfolipases A2 Independentes de Cálcio/metabolismo , Fosfolipases A2/metabolismo , Reflexo de Sobressalto/fisiologia , Estimulação Acústica , Análise de Variância , Animais , Inibidores Enzimáticos/farmacologia , Masculino , Oligonucleotídeos Antissenso/farmacologia , Inibidores de Fosfolipase A2 , Fosfolipases A2 Independentes de Cálcio/antagonistas & inibidores , Fosfolipases A2 Independentes de Cálcio/genética , Quinacrina/farmacologia , Ratos , Ratos Wistar
15.
J Orofac Pain ; 23(2): 167-73, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19492541

RESUMO

AIMS: To evaluate possible effects of the intracerebroventricular (icv) injection of either O-Tricyclo [5.2.1.0(2,6)] dec-9-yl dithiocarbonate potassium salt (D609), a potent antioxidant and inhibitor of phosphatidylcholine specific phospholipase C (PtdCho-PLC) and acid sphingomyelinase (ASMase), or the spin trap/free radical scavenger N-tert-Butyl-alpha-phenylnitrone (PBN), on mechanical allodynia induced by facial carrageenan injection in mice. METHODS: Balb/c mice received icy injection of D609/PBN plus facial carrageenan injection, and the number of face wash strokes to von Frey hair mechanical stimulation of the maxillary skin was quantified. PtdCho-PLC and ASMase activities were also assayed in the brainstem, thalamus, and somatosensory cortex. RESULTS: Mice that received the icy injection of 10 nmol D609 plus facial carrageenan injection showed significantly fewer face wash strokes evoked by von Frey hair stimulation (indicating reduced mechanical allodynia) at 1 and 3 days post-injection, compared to mice that received icy injection of isotonic saline plus facial carrageenan injection. Mice that received icy injection of 1.13 micromol PBN plus facial carrageenan injection likewise showed significantly fewer face wash strokes after facial carrageenan injection, compared to isotonic saline-injected plus carrageenan-injected controls. D609 injection also resulted in significantly reduced ASMase activity in the brainstem, thalamus, and somatosensory cortex 3 days after injection, compared to controls. CONCLUSION: The icv injections of D609 and PBN were effective in reducing mechanical allodynia after facial carrageenan injection-induced pain. Together, the results point to a possible role of central nervous system sphingolipids and/or free radicals in orofacial pain.


Assuntos
Antioxidantes/uso terapêutico , Encéfalo/enzimologia , Dor Facial/tratamento farmacológico , Sequestradores de Radicais Livres/uso terapêutico , Nervo Maxilar/efeitos dos fármacos , Gânglio Trigeminal/efeitos dos fármacos , Animais , Antioxidantes/administração & dosagem , Encéfalo/efeitos dos fármacos , Tronco Encefálico/efeitos dos fármacos , Tronco Encefálico/enzimologia , Hidrocarbonetos Aromáticos com Pontes/administração & dosagem , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Carragenina/efeitos adversos , Ventrículos Cerebrais/efeitos dos fármacos , Ventrículos Cerebrais/enzimologia , Óxidos N-Cíclicos/administração & dosagem , Óxidos N-Cíclicos/uso terapêutico , Modelos Animais de Doenças , Dor Facial/induzido quimicamente , Sequestradores de Radicais Livres/administração & dosagem , Injeções Intraventriculares , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Norbornanos , Córtex Somatossensorial/efeitos dos fármacos , Córtex Somatossensorial/enzimologia , Esfingolipídeos/metabolismo , Esfingomielina Fosfodiesterase/antagonistas & inibidores , Estimulação Química , Tálamo/efeitos dos fármacos , Tálamo/enzimologia , Tiocarbamatos , Tionas/administração & dosagem , Tionas/uso terapêutico , Fosfolipases Tipo C/antagonistas & inibidores
16.
Exp Brain Res ; 186(1): 143-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18040670

RESUMO

Our previous study showed an increase in total cholesterol level of the hippocampus after kainate-induced injury, but whether this is further metabolized to neurosteroids is not known. The first step in neurosteroid biosynthesis is the conversion of cholesterol to pregnenolone by the enzyme cytochrome P450 side chain cleavage (P450scc). This study was carried out to elucidate the expression of this enzyme in the kainate-lesioned rat hippocampus. A net decrease in P450scc protein was detected in hippocampal homogenates by Western blots at 2 weeks post-kainate injection (time of peak cholesterol concentration after kainate injury). Immunohistochemistry showed decreased labeling of the enzyme in neurons, but increased expression in a small number of astrocytes. The level of pregnenolone was also analyzed using a newly developed gas chromatography-mass spectrometry (GC-MS) method, optimized for the rat hippocampus. A non-significant tendency to a decrease in pregnenolone level was detected 2 weeks post-lesion. This is in contrast to a large increase in oxysterols in the lesioned hippocampus at this time (He et al. 2006). Together, they indicate that increased cholesterol in the kainate lesioned hippocampus is mostly metabolized to oxysterols, and not neurosteroids.


Assuntos
Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Ácido Caínico/toxicidade , Animais , Western Blotting , Enzima de Clivagem da Cadeia Lateral do Colesterol/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Hipocampo/efeitos dos fármacos , Hipocampo/enzimologia , Hipocampo/lesões , Injeções Intraperitoneais , Ácido Caínico/administração & dosagem , Cinética , Pregnenolona/metabolismo , Ratos , Ratos Wistar , Fatores de Tempo
17.
Brain Res Rev ; 56(2): 443-71, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17959252

RESUMO

Neural membranes are composed of glycerophospholipids, sphingolipids, cholesterol and proteins. The distribution of these lipids within the neural membrane is not random but organized. Neural membranes contain lipid rafts or microdomains that are enriched in sphingolipids and cholesterol. These rafts act as platforms for the generation of glycerophospholipid-, sphingolipid-, and cholesterol-derived second messengers, lipid mediators that are necessary for normal cellular function. Glycerophospholipid-derived lipid mediators include eicosanoids, docosanoids, lipoxins, and platelet-activating factor. Sphingolipid-derived lipid mediators include ceramides, ceramide 1-phosphates, and sphingosine 1-phosphate. Cholesterol-derived lipid mediators include 24-hydroxycholesterol, 25-hydroxycholesterol, and 7-ketocholesterol. Abnormal signal transduction processes and enhanced production of lipid mediators cause oxidative stress and inflammation. These processes are closely associated with the pathogenesis of acute neural trauma (stroke, spinal cord injury, and head injury) and neurodegenerative diseases such as Alzheimer disease. Statins, the HMG-CoA reductase inhibitors, are effective lipid lowering agents that significantly reduce risk for cardiovascular and cerebrovascular diseases. Beneficial effects of statins in neurological diseases are due to their anti-excitotoxic, antioxidant, and anti-inflammatory properties. Fish oil omega-3 fatty acids, eicosapentaenoic acid and docosahexaenoic acid, have similar anti-excitotoxic, antioxidant and anti-inflammatory effects in brain tissue. Thus the lipid mediators, resolvins, protectins, and neuroprotectins, derived from eicosapentaenoic acid and docosahexaenoic acid retard neuroinflammation, oxidative stress, and apoptotic cell death in brain tissue. Like statins, ingredients of fish oil inhibit generation of beta-amyloid and provide protection from oxidative stress and inflammatory processes. Collective evidence suggests that antioxidant, anti-inflammatory, and anti-apoptotic properties of statins and fish oil contribute to the clinical efficacy of treating neurological disorders with statins and fish oil. We speculate that there is an overlap between neurochemical events associated with neural cell injury in stroke and neurodegenerative diseases. This commentary compares the neurochemical effects of statins with those of fish oil.


Assuntos
Encéfalo/efeitos dos fármacos , Óleos de Peixe/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Animais , Química Encefálica/efeitos dos fármacos , Colesterol/biossíntese , Humanos , Inflamação/fisiopatologia , Inflamação/prevenção & controle , Lipídeos/fisiologia , Doenças do Sistema Nervoso/tratamento farmacológico , Doenças do Sistema Nervoso/fisiopatologia , Fenômenos Fisiológicos da Nutrição , Estresse Oxidativo/efeitos dos fármacos
18.
J R Coll Physicians Edinb ; 48(3): 198-201, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30191906

RESUMO

BACKGROUND: Malaria remains an endemic disease in Pakistan with an estimated healthcare burden of 1.6 million cases annually, with Plasmodium vivax accounting for 67% of reported cases. P. vivax is the most common species causing malaria outside of Africa, with approximately 13.8 million reported cases worldwide. METHOD: We report a series of P. vivax cases with cerebral involvement that presented at Aga Khan University Hospital, Karachi, Pakistan. RESULTS: The majority of the patients presented with high-grade fever accompanied by projectile vomiting and abnormal behaviour, seizures, shock and unconsciousness. Seven of 801 patients with P. vivax monoinfection presented or developed cerebral complications. P. vivax infections were diagnosed based on peripheral smears and rapid diagnostic testing. CONCLUSION: P. vivax infection can lead to severe complications, although not with the frequency of Plasmodium falciparum infection. Current cases highlight an increasing trend of cerebral complications caused by P. vivax.


Assuntos
Malária Vivax/complicações , Doenças do Sistema Nervoso/parasitologia , Adulto , Idoso , Febre/parasitologia , Humanos , Imageamento por Ressonância Magnética , Malária Vivax/diagnóstico , Malária Vivax/tratamento farmacológico , Masculino , Transtornos Mentais/parasitologia , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/complicações , Doenças do Sistema Nervoso/diagnóstico por imagem , Paquistão , Estudos Retrospectivos , Convulsões/parasitologia , Choque/parasitologia , Inconsciência/parasitologia , Vômito/parasitologia , Adulto Jovem
19.
Mol Neurobiol ; 55(9): 7389-7400, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29417476

RESUMO

The Traditional Chinese Medicine (TCM) theory that "kidneys give rise to marrow, and the brain is the sea of marrow" has been a guide for the clinical application of kidney, qi and blood tonics for prevention and treatment of dementia and improvement in memory. As low resistance end-organs, both the brain and the kidneys are subjected to blood flow of high volumes throughout the cardiac cycle. Alzheimer's disease and vascular dementia are two common causes of dementia, and it is increasingly recognized that many older adults with dementia have both AD and vascular pathologies. The underlying molecular mechanisms are incompletely understood, but may involve atherosclerosis, vascular dysfunction, hypertension, type 2 diabetes, history of cardiac disease and possibly, kidney dysfuntion, leading to reduced erythropoietin production, anemia, brain energy deficit and slow excitotoxicity. During the Ming Dynasty, Zhang Jing-Yue used Qi Fu Yin (seven blessings decoction), comprising Panax ginseng, Rehmannia glutinosa, Angelica polymorpha, Atractylodes macrocephala, Glycyrrhiza uralensis, Ziziphus jujube, and Polygala tenuifolia to boost qi and blood circulation, strengthen the heart, and calm the spirit-skillfully linking heart, spleen, kidney, qi, blood and brain as a whole to treat age-related dementia. The purpose of this review is to outline TCM concepts for the treatment of dementia and illustrated with a historical prescription for the treatment of the condition, with the hope that this description may lead to advances in its management.


Assuntos
Demência/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa , Encéfalo/patologia , Medicamentos de Ervas Chinesas/efeitos adversos , Humanos , Rim/patologia , Compostos Fitoquímicos/análise
20.
Artigo em Inglês | MEDLINE | ID: mdl-29861767

RESUMO

Ayurvedic medicine is a personalized system of traditional medicine native to India and the Indian subcontinent. It is based on a holistic view of treatment which promotes and supports equilibrium in different aspects of human life: the body, mind, and soul. Popular Ayurvedic medicinal plants and formulations that are used to slow down brain aging and enhance memory include Ashwagandha (Withania somnifera), Turmeric (Curcuma longa), Brahmi (Bacopa monnieri), Shankhpushpi (Convolvulus pluricaulis, Evolvulus alsinoides, and other species), gotu kola (Centella asiatica), and guggulu (Commiphora mukul and related species) and a formulation known as Brahmi Ghrita, containing Brahmi, Vaca (Acorus calamus), Kustha (Saussurea lappa), Shankhpushpi, and Purana Ghrita (old clarified butter/old ghee). The rationale for the utilization of Ayurvedic medicinal plants has depended mostly on traditional usage, with little scientific data on signal transduction processes, efficacy, and safety. However, in recent years, pharmacological and toxicological studies have begun to be published and receive attention from scientists for verification of their claimed pharmacological and therapeutic effects. The purpose of this review is to outline the molecular mechanisms, signal transduction processes, and sites of action of some Ayurvedic medicinal plants. It is hoped that this description can be further explored with modern scientific methods, to reveal new therapeutic leads and jump-start more studies on the use of Ayurvedic medicine for prevention and treatment of dementia.

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