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1.
Am J Hum Genet ; 110(8): 1356-1376, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37421948

RESUMO

By converting physical forces into electrical signals or triggering intracellular cascades, stretch-activated ion channels allow the cell to respond to osmotic and mechanical stress. Knowledge of the pathophysiological mechanisms underlying associations of stretch-activated ion channels with human disease is limited. Here, we describe 17 unrelated individuals with severe early-onset developmental and epileptic encephalopathy (DEE), intellectual disability, and severe motor and cortical visual impairment associated with progressive neurodegenerative brain changes carrying ten distinct heterozygous variants of TMEM63B, encoding for a highly conserved stretch-activated ion channel. The variants occurred de novo in 16/17 individuals for whom parental DNA was available and either missense, including the recurrent p.Val44Met in 7/17 individuals, or in-frame, all affecting conserved residues located in transmembrane regions of the protein. In 12 individuals, hematological abnormalities co-occurred, such as macrocytosis and hemolysis, requiring blood transfusions in some. We modeled six variants (p.Val44Met, p.Arg433His, p.Thr481Asn, p.Gly580Ser, p.Arg660Thr, and p.Phe697Leu), each affecting a distinct transmembrane domain of the channel, in transfected Neuro2a cells and demonstrated inward leak cation currents across the mutated channel even in isotonic conditions, while the response to hypo-osmotic challenge was impaired, as were the Ca2+ transients generated under hypo-osmotic stimulation. Ectopic expression of the p.Val44Met and p.Gly580Cys variants in Drosophila resulted in early death. TMEM63B-associated DEE represents a recognizable clinicopathological entity in which altered cation conductivity results in a severe neurological phenotype with progressive brain damage and early-onset epilepsy associated with hematological abnormalities in most individuals.


Assuntos
Encefalopatias , Deficiência Intelectual , Humanos , Encefalopatias/genética , Canais Iônicos/genética , Encéfalo , Deficiência Intelectual/genética , Fenótipo
2.
Glia ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38864289

RESUMO

Astrocytes play an essential role in regulating synaptic transmission. This study describes a novel form of modulation of excitatory synaptic transmission in the mouse hippocampus by astrocytic G-protein-coupled receptors (GPCRs). We have previously described astrocytic glutamate release via protease-activated receptor-1 (PAR1) activation, although the regulatory mechanisms for this are complex. Through electrophysiological analysis and modeling, we discovered that PAR1 activation consistently increases the concentration and duration of glutamate in the synaptic cleft. This effect was not due to changes in the presynaptic glutamate release or alteration in glutamate transporter expression. However, blocking group II metabotropic glutamate receptors (mGluR2/3) abolished PAR1-mediated regulation of synaptic glutamate concentration, suggesting a role for this GPCR in mediating the effects of PAR1 activation on glutamate release. Furthermore, activation of mGluR2/3 causes glutamate release through the TREK-1 channel in hippocampal astrocytes. These data show that astrocytic GPCRs engage in a novel regulatory mechanism to shape the time course of synaptically-released glutamate in excitatory synapses of the hippocampus.

3.
Mol Biol Rep ; 51(1): 548, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38642142

RESUMO

INTRODUCTION: Paracetamol (acetaminophen) overdose is a leading cause of acute liver failure in many Western countries. Diagnostic tools for this poisoning may be suboptimal in some cases and new biomarkers have been investigated. We investigated the role of capillary microRNA-122 (miR-122) as a prognostic biomarker of liver injury in the clinical management of patients with paracetamol overdose. METHODS: In a paracetamol overdose patient cohort, miR-122 was measured by quantitative polymerase chain reaction in a blood drop obtained by a finger prick at the end of an antidote cycle treatment with N-acetylcysteine treatment (12 h). Liver injury was defined as serum alanine aminotransferase (ALT) activity > 100 IU/L collected at 10 or 20 h after the start of treatment. Pearson's correlation analyses were performed. RESULTS: In patients with paracetamol overdose, capillary miR-122 was positively correlated with ALT measured at 10 h and at 20 h (r = 0.83, P < 0.0001; r = 0.96, P < 0.0001, respectively). CONCLUSION: This work supports the potential use of capillary miR-122 as a prognostic biomarker of liver injury throughout clinical management of patients with paracetamol overdose. Capillary miR-122 can be measured in a blood drop collected by a finger prick, a minimally invasive diagnostic test for patient stratification.


Assuntos
Analgésicos não Narcóticos , Doença Hepática Crônica Induzida por Substâncias e Drogas , Doença Hepática Induzida por Substâncias e Drogas , MicroRNAs , Humanos , Acetaminofen/efeitos adversos , Biomarcadores , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , MicroRNAs/sangue , MicroRNAs/genética , Prognóstico , Doença Hepática Crônica Induzida por Substâncias e Drogas/diagnóstico , Doença Hepática Crônica Induzida por Substâncias e Drogas/genética
4.
Eur J Clin Pharmacol ; 78(9): 1511-1519, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35732964

RESUMO

PURPOSE: Benzodiazepines (BZD), Z-drugs (ZD), and opioids share a high risk of abuse. This study assessed and characterised adverse events (AEs) related to BDZ, ZD, and opioids leading to emergency department (ED) visits in the Italian setting. METHODS: ED accesses related to BDZ, ZD, and/or opioids were analysed from the MEREAFaPS database. Information on AEs, suspected and concomitant medications was retrieved. Multivariate logistic regression was used to estimate the reporting odds ratios (RORs) of hospitalisation according to the different treatments. RESULTS: A total of 5,970 pharmacovigilance reports involving BZD/ZD (n = 3,106), opioids (n = 2,767), or their combination (n = 97) were analysed. Compared to opioids, patients with BZD/ZD-related AEs were often younger (51 vs 64 years), more frequently presented 2+ suspected medications (13 vs 3%), and often had a history of abuse (4%). Twenty-three percent of BZD/ZD-related AEs were related to drug abuse (vs 2% of opioid-related ones) and frequently required patient hospitalisation (52% vs 24%), despite the significantly lower clinical complexity of these patients as compared to those on opioids. An increased risk of hospitalisation was found for flurazepam (ROR 1.62; 95% CI, 1.18-2.22), prazepam (2.66; 1.05-6.70), lorazepam (1.26; 1.07-1.49), and morphine (1.76; 1.11-2.79). CONCLUSIONS: These results indicate that, in Italy, the inappropriate use of BZD/ZD is a relevant heath issue, often leading to serious AEs requiring patients' ED visits and hospitalisation, especially in young women and patients with a history of substance abuse.


Assuntos
Benzodiazepinas , Transtornos Relacionados ao Uso de Substâncias , Analgésicos Opioides/efeitos adversos , Benzodiazepinas/efeitos adversos , Serviço Hospitalar de Emergência , Feminino , Hospitalização , Humanos , Transtornos Relacionados ao Uso de Substâncias/tratamento farmacológico , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
5.
Int J Mol Sci ; 23(3)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35163344

RESUMO

The complexity of microglia phenotypes and their related functions compels the continuous study of microglia in diseases animal models. We demonstrated that oxygen-glucose deprivation (OGD) induced rapid, time- and space-dependent phenotypic microglia modifications in CA1 stratum pyramidalis (SP) and stratum radiatum (SR) of rat organotypic hippocampal slices as well as the degeneration of pyramidal neurons, especially in the outer layer of SP. Twenty-four h following OGD, many rod microglia formed trains of elongated cells spanning from the SR throughout the CA1, reaching the SP outer layer where they acquired a round-shaped amoeboid phagocytic head and phagocytosed most of the pyknotic, damaged neurons. NIR-laser treatment, known to preserve neuronal viability after OGD, prevented rod microglia formation. In CA3 SP, pyramidal neurons were less damaged, no rod microglia were found. Thirty-six h after OGD, neuronal damage was more pronounced in SP outer and inner layers of CA1, rod microglia cells were no longer detectable, and most microglia were amoeboid/phagocytic. Damaged neurons, more numerous 36 h after OGD, were phagocytosed by amoeboid microglia in both inner and outer layers of CA1. In response to OGD, microglia can acquire different morphofunctional phenotypes which depend on the time after the insult and on the subregion where microglia are located.


Assuntos
Hipocampo , Microglia , Animais , Glucose , Hipóxia , Isquemia , Oxigênio , Fenótipo , Ratos
6.
J Neurochem ; 157(6): 2106-2118, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33107046

RESUMO

Modifications in the subunit composition of AMPA receptors (AMPARs) have been linked to the transition from physiological to pathological conditions in a number of contexts, including EtOH-induced neurotoxicity. Previous work from our laboratory showed that EtOH withdrawal causes CA1 pyramidal cell death in organotypic hippocampal slices and changes in the expression of AMPARs. Here, we investigated whether changes in expression and function of AMPARs may be causal for EtOH-induced neurotoxicity. To this aim, we examined the subunit composition, localization and function of AMPARs in hippocampal slices exposed to EtOH by using western blotting, surface expression assay, confocal microscopy and electrophysiology. We found that EtOH withdrawal specifically increases GluA1 protein signal in total homogenates, but not in the post-synaptic density-enriched fraction. This is suggestive of overall increase and redistribution of AMPARs to the extrasynaptic compartment. At functional level, AMPA-induced calcium influx was unexpectedly reduced, whereas AMPA-induced current was enhanced in CA1 pyramidal neurons following EtOH withdrawal, suggesting that increased AMPAR expression may lead to cell death because of elevated excitability, and not for a direct contribution on calcium influx. Finally, the neurotoxicity caused by EtOH withdrawal was attenuated by the non-selective AMPAR antagonist 2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenzo[f]quinoxaline-7-sulfonamide disodium salt as well as by the selective antagonist of GluA2-lacking AMPARs 1-naphthyl acetyl spermine. We conclude that EtOH neurotoxicity involves changes in expression, surface localization and functional properties of AMPARs, and propose GluA2-lacking AMPARs as amenable specific targets for the development of neuroprotective drugs in EtOH-withdrawal syndrome.


Assuntos
Etanol/toxicidade , Regulação da Expressão Gênica , Ácido Glutâmico/metabolismo , Hipocampo/metabolismo , Receptores de AMPA/metabolismo , Animais , Antagonistas de Aminoácidos Excitatórios/farmacologia , Feminino , Citometria de Fluxo/métodos , Ácido Glutâmico/análise , Hipocampo/química , Hipocampo/efeitos dos fármacos , Masculino , Técnicas de Cultura de Órgãos , Ratos , Ratos Wistar , Receptores de AMPA/análise , Receptores de AMPA/antagonistas & inibidores
7.
Br J Clin Pharmacol ; 87(3): 741-753, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32656820

RESUMO

AIMS: Several cases of acute non-infectious cholestatic hepatitis recently appeared in Italy following consumption of Curcuma longa-containing dietary supplements. The aim of this research was to describe the Tuscan (Italy) cases of acute hepatitis and to compare them with similar cases of hepatotoxicity published in the literature by performing a systematic review. METHODS: Records of Tuscan cases of acute hepatitis were obtained from the Italian Phytovigilance system. Each spontaneous report was analysed in order to collect all relevant clinical information of patients and information concerning the Curcuma longa-containing dietary supplement. Moreover, both the RUCAM and WHO-UMC systems were used to evaluate the causal relationship between the use of dietary supplement and acute hepatitis. A systematic literature review was performed in MEDLINE and Embase and all case-reports and case-series published in English were included. RESULTS: Seven cases of acute hepatitis occurring in Tuscany up to September 2019 are described. In all cases, hepatotoxicity was associated with Curcuma longa formulations with high bioavailability and high dosage of curcumin/curcuminoids. The causal relationship was also supported by the positive dechallenge observed in most cases. In the 23 cases identified through the systematic review, the majority of patients were concomitantly exposed to at least one other medication and 16 of them experienced a positive dechallenge. CONCLUSIONS: Within the frame of poorly controlled and regulated products, such as dietary supplements, the evaluation of Italian cases of Curcuma longa-induced acute hepatitis and the systematic review of literature confirmed the association between Curcuma longa and liver injury.


Assuntos
Curcuma , Curcumina , Curcumina/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Humanos , Itália/epidemiologia , Fígado , Extratos Vegetais
8.
Acta Neurol Scand ; 143(2): 121-130, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32866996

RESUMO

Electronic cigarettes are a popular, easily purchased, alternative source of nicotine that is considered safer than conventional tobacco. However, Intentional or accidental exposure to e-liquid substances, mainly nicotine, can lead to serious, potentially fatal toxicity. Emergency and critical care physicians should keep in mind acute intoxication of this poison with a biphasic toxic syndrome. We highlight its potentially fatal outcome and suggest monitoring the adverse effects of nicotine according to a multimodal protocol integrating somatosensory evoked potentials, electroencephalography and neuroimaging data with anamnestic report and toxicological and laboratory data.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Síndromes Neurotóxicas/diagnóstico , Nicotina/toxicidade , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Humanos , Síndromes Neurotóxicas/epidemiologia , Síndromes Neurotóxicas/etiologia , Nicotina/intoxicação , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/etiologia
9.
Neurol Sci ; 42(3): 987-994, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32691178

RESUMO

OBJECTIVES: A refractory chronic migraine (RCM) accompanied by medication-overuse headache (MOH) is an extremely disabling disease. Evidence suggests that in selected patients, chronic opioids may be a valuable therapeutic option for RCM. The aim of the present study was to evaluate the effectiveness and safety of prophylaxis with low-dose methadone (LDM) in patients affected by RCM with continuous headache and MOH. METHODS: A prospective cohort study was performed between May 2012 and November 2015 at the Headache Center and Toxicology Unit of the Careggi University Hospital. Eligible patients were treated with prophylactic LDM and followed up for 12 months. Headache exacerbations, pain intensity, use of rescue medications, and occurrence of adverse drug reactions (ADRs) were recorded. RESULTS: Thirty patients (24 females, median age 48 years) were enrolled. Nineteen (63%) patients dropped out, mainly because of early ADRs (n = 10), including nausea, vomiting, and constipation. At last available follow-up, LDM was associated with a significant decrease in the number of headache attacks/month (from a median of 45 (interquartile range 30-150) to 16 (5-30), p < 0.001), in pain intensity (from 8.5 (8-9) to 5 (3-6), p < 0.001), and in the number of rescue medications consumed per month (from 95 (34-240) to 15 (3-28), p < 0.001). No misuse or diversion cases were observed. CONCLUSION: LDM could represent a valuable and effective option in selected patients affected by RCM with continuous headache and MOH, although the frequency of early ADRs poses major safety concerns. Randomized controlled trials are needed to confirm the efficacy and safety of LDM prophylaxis.


Assuntos
Transtornos da Cefaleia Secundários , Transtornos de Enxaqueca , Feminino , Cefaleia , Transtornos da Cefaleia Secundários/tratamento farmacológico , Humanos , Metadona/efeitos adversos , Pessoa de Meia-Idade , Transtornos de Enxaqueca/tratamento farmacológico , Estudos Prospectivos
10.
J Neurochem ; 155(6): 638-649, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32343420

RESUMO

We investigated the molecular events triggered by NMDA and 3,5-dihydroxyphenylglycine (DHPG) preconditioning, that lead to neuroprotection against excitotoxic insults (AMPA or oxygen and glucose deprivation) in rat organotypic hippocampal slices, with particular attention on glutamate receptors and on cannabinoid system. We firstly evaluated the protein expression of NMDA and AMPA receptor subunits after preconditioning using western blot analysis performed in post-synaptic densities. We observed that following NMDA, but not DHPG preconditioning, the expression of GluA1 was significantly reduced and this reduction appeared to be associated with the internalization of AMPA receptors. Whole-cell voltage clamp recordings on CA1 pyramidal neurons of organotypic slices show that 24 hr after exposure to NMDA and DHPG preconditioning, AMPA-induced currents were significantly reduced. To clarify the mechanisms induced by DHPG preconditioning, we then investigated the involvement of the endocannabinoid system. Exposure of slices to the CB1 antagonist AM251 prevented the development of tolerance to AMPA toxicity induced by DHPG but not NMDA. Accordingly, the MAG-lipase inhibitor URB602, that increases arachidonoylglycerol (2-AG) content, but not the FAAH inhibitor URB597, that limits the degradation of anandamide, was also able to induce tolerance versus AMPA and OGD toxicity, suggesting that 2-AG is responsible for the DHPG-induced tolerance. In conclusion, preconditioning with NMDA or DHPG promotes differential neuroprotective mechanisms: NMDA by internalization of GluA1-AMPA receptors, DHPG by producing the endocannabinoid 2-AG.


Assuntos
Tolerância a Medicamentos/fisiologia , Glicina/análogos & derivados , Hipocampo/metabolismo , Precondicionamento Isquêmico/métodos , N-Metilaspartato/farmacologia , Neuroproteção/fisiologia , Resorcinóis/farmacologia , Animais , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Agonistas de Aminoácidos Excitatórios/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Feminino , Glucose/deficiência , Glicina/farmacologia , Hipocampo/irrigação sanguínea , Hipocampo/efeitos dos fármacos , Masculino , Neuroproteção/efeitos dos fármacos , Técnicas de Cultura de Órgãos , Ratos , Ratos Wistar , Receptores de AMPA/antagonistas & inibidores , Receptores de AMPA/metabolismo
11.
Pharmacol Rev ; 69(4): 354-395, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28878030

RESUMO

Hyperpolarization-activated, cyclic nucleotide-gated (HCN) channels are important members of the voltage-gated pore loop channels family. They show unique features: they open at hyperpolarizing potential, carry a mixed Na/K current, and are regulated by cyclic nucleotides. Four different isoforms have been cloned (HCN1-4) that can assemble to form homo- or heterotetramers, characterized by different biophysical properties. These proteins are widely distributed throughout the body and involved in different physiologic processes, the most important being the generation of spontaneous electrical activity in the heart and the regulation of synaptic transmission in the brain. Their role in heart rate, neuronal pacemaking, dendritic integration, learning and memory, and visual and pain perceptions has been extensively studied; these channels have been found also in some peripheral tissues, where their functions still need to be fully elucidated. Genetic defects and altered expression of HCN channels are linked to several pathologies, which makes these proteins attractive targets for translational research; at the moment only one drug (ivabradine), which specifically blocks the hyperpolarization-activated current, is clinically available. This review discusses current knowledge about HCN channels, starting from their biophysical properties, origin, and developmental features, to (patho)physiologic role in different tissues and pharmacological modulation, ending with their present and future relevance as drug targets.


Assuntos
Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/antagonistas & inibidores , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/química , Animais , Biofísica , Humanos , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/fisiologia , Ligantes , Terapia de Alvo Molecular , Nucleotídeos Cíclicos/química , Nucleotídeos Cíclicos/farmacologia , Relação Estrutura-Atividade
12.
Eur Addict Res ; 24(1): 9-18, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29393208

RESUMO

AIMS: We aimed to improve the retention in treatment and therapeutic outcome of methadone maintenance treatment (MMT) patients by adjusting the oral methadone dose in order to reach a "target" plasma R-methadone level (80-250 ng/mL). METHODS: A multicenter randomized controlled trial was organized. RESULTS: The intention-to-treat statistical analysis showed that repeated dose adjustments performed in order to obtain therapeutic plasma R-methadone levels did not improve retention in treatment of heroin-dependent patients. However, patients having plasma methadone levels in the "target range" at the beginning of the study had a better retention in treatment than controls. Furthermore, patients succeeding in keeping plasma R-methadone target levels (per protocol analysis) remained in treatment and improved their social scores better than controls. -Conclusion: Although the primary endpoint of this study was not demonstrated, a post hoc and a per protocol analysis suggested that patients in MMT with plasma R-methadone concentrations in the target range have a better therapeutic outcome than controls.


Assuntos
Analgésicos Opioides/uso terapêutico , Metadona/uso terapêutico , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Adulto , Feminino , Humanos , Masculino , Metadona/sangue , Tratamento de Substituição de Opiáceos/métodos , Fatores de Tempo , Resultado do Tratamento
13.
J Cell Mol Med ; 21(2): 324-335, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27704718

RESUMO

Idiopathic pulmonary fibrosis is a severe disease characterized by excessive myofibroblast proliferation, extracellular matrix and fibrils deposition, remodelling of lung parenchyma and pulmonary insufficiency. Drugs able to reduce disease progression are available, but therapeutic results are unsatisfactory; new and safe treatments are urgently needed. Poly(ADP-ribose) polymerases-1 (PARP-1) is an abundant nuclear enzyme involved in key biological processes: DNA repair, gene expression control, and cell survival or death. In liver and heart, PARP-1 activity facilitates oxidative damage, collagen deposition and fibrosis development. In this study, we investigated the effects of HYDAMTIQ, a potent PARP-1 inhibitor, in a murine model of lung fibrosis. We evaluated the role of PARP on transforming growth factor-ß (TGF-ß) expression and TGF-ß/SMAD signalling pathway in lungs. Mice were intratracheally injected with bleomycin and then treated with either vehicle or different doses of HYDAMTIQ for 21 days. Airway resistance to inflation and lung static compliance, markers of lung stiffness, were assayed. Histochemical and biochemical parameters to evaluate TGF-ß/SMAD signalling pathway with alpha-smooth muscle actin (αSMA) deposition and the levels of a number of inflammatory markers (tumour necrosis factor-α, interleukin-1ß, iNOS and COX-2) were performed. Bleomycin administration increased lung stiffness. It also increased lung PARP activity, TGF-ß levels, pSMAD3 expression, αSMA deposition and content of inflammatory markers. HYDAMTIQ attenuated all the above-mentioned physiological, biochemical and histopathological markers. Our findings support the proposal that PARP inhibitors could have a therapeutic potential in reducing the progression of signs and symptoms of the disease by decreasing TGF-ß expression and the TGF-ß/SMAD transduction pathway.


Assuntos
Isoquinolinas/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/enzimologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/metabolismo , Tiofenos/uso terapêutico , Fator de Crescimento Transformador beta/metabolismo , Actinas/metabolismo , Animais , Biomarcadores/metabolismo , Bleomicina , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Hidroxiprolina/metabolismo , Mediadores da Inflamação/metabolismo , Isoquinolinas/farmacologia , Pulmão/patologia , Pulmão/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Fibrose Pulmonar/induzido quimicamente , Tiofenos/farmacologia
14.
Biophys J ; 111(9): 2024-2038, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27806283

RESUMO

Transthyretin (TTR) amyloidoses are familial or sporadic degenerative conditions that often feature heavy cardiac involvement. Presently, no effective pharmacological therapy for TTR amyloidoses is available, mostly due to a substantial lack of knowledge about both the molecular mechanisms of TTR aggregation in tissue and the ensuing functional and viability modifications that occur in aggregate-exposed cells. TTR amyloidoses are of particular interest regarding the relation between functional and viability impairment in aggregate-exposed excitable cells such as peripheral neurons and cardiomyocytes. In particular, the latter cells provide an opportunity to investigate in parallel the electrophysiological and biochemical modifications that take place when the cells are exposed for various lengths of time to variously aggregated wild-type TTR, a condition that characterizes senile systemic amyloidosis. In this study, we investigated biochemical and electrophysiological modifications in cardiomyocytes exposed to amyloid oligomers or fibrils of wild-type TTR or to its T4-stabilized form, which resists tetramer disassembly, misfolding, and aggregation. Amyloid TTR cytotoxicity results in mitochondrial potential modification, oxidative stress, deregulation of cytoplasmic Ca2+ levels, and Ca2+ cycling. The altered intracellular Ca2+ cycling causes a prolongation of the action potential, as determined by whole-cell recordings of action potentials on isolated mouse ventricular myocytes, which may contribute to the development of cellular arrhythmias and conduction alterations often seen in patients with TTR amyloidosis. Our data add information about the biochemical, functional, and viability alterations that occur in cardiomyocytes exposed to aggregated TTR, and provide clues as to the molecular and physiological basis of heart dysfunction in sporadic senile systemic amyloidosis and familial amyloid cardiomyopathy forms of TTR amyloidoses.


Assuntos
Amiloide/química , Amiloide/metabolismo , Fenômenos Eletrofisiológicos , Miócitos Cardíacos/metabolismo , Pré-Albumina/química , Pré-Albumina/metabolismo , Agregados Proteicos , Animais , Cálcio/metabolismo , Citoplasma/metabolismo , Ventrículos do Coração/citologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL
15.
Clin Sci (Lond) ; 130(20): 1793-806, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27439970

RESUMO

Berberine (BRB) is commonly used in herbal medicine, but its mechanisms of action are poorly understood. In the present study, we tested BRB in steatohepatitis induced by a methionine- and choline-deficient (MCD) diet, in acute acetaminophen intoxication and in cultured murine macrophages. BRB markedly improved parameters of liver injury and necroinflammation induced by the MCD diet, although increased mortality was observed by mechanisms independent of bacterial infections or plasma levels of BRB. The MCD diet induced up-regulation of all components of the NLRP3 (NACHT, LRR and PYD domain-containing protein 3) inflammasome, and increased hepatic levels of mature IL-1ß (interleukin 1ß). All of these parameters were significantly reduced in mice treated with BRB. In mice administered an acetaminophen overdose, a model dependent on inflammasome activation, BRB reduced mortality and ALT (alanine aminotransferase) elevation, and limited the expression of inflammasome components. In vitro, LPS (lipopolysaccharide)-induced activation of NLRP3 inflammasome in RAW264.7 murine macrophages was markedly decreased by pre-incubation with BRB. BRB significantly limited the activation of the purinergic receptor P2X7, involved in the late phases of inflammasome activation. Upon P2X7 knockdown, the ability of BRB to block LPS-induced secretion of IL-1ß was lost. These data indicate that administration of BRB ameliorates inflammation and injury in two unrelated murine models of liver damage. We demonstrate for the first time that BRB interferes with activation of the NLRP3 inflammasome pathway in vivo and in vitro, through a mechanism based on interference with activation of P2X7, a purinergic receptor involved in inflammasome activation.


Assuntos
Acetaminofen/efeitos adversos , Berberina/administração & dosagem , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Inflamassomos/metabolismo , Animais , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Humanos , Inflamassomos/efeitos dos fármacos , Inflamassomos/genética , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Transdução de Sinais
16.
Alcohol Clin Exp Res ; 40(4): 706-16, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27038592

RESUMO

BACKGROUND: The developing brain is particularly vulnerable to alcohol: Drinking during pregnancy can lead to a number of physical, learning, and behavioral disorders in the newborn. It has been demonstrated that immature and mature brain tissues display a differential sensitivity to ethanol (EtOH) toxicity and that cerebral structure and function are diversely impaired according to the stage of synaptic maturation. METHODS: Rat organotypic hippocampal slice cultures were exposed for 7 days to EtOH (100 to 300 mM) after 2 days (immature) or 10 days (mature) of culture in vitro; EtOH was then removed from the medium, and 24 hours later, slices were analyzed by fluorescence microscopy, Western blotting, electrophysiology, and electron microscopy to explore the molecular mechanisms of EtOH toxicity in the developing hippocampus. RESULTS: EtOH withdrawal elicited a selective CA1 pyramidal cell injury in mature slices, but not in immature slices. A significant increase in the expression of pre- and postsynaptic proteins in mature slices revealed that slice maturation is presumably associated with the development of new synapses. Incubation with chronic EtOH for 7 days and its removal from the medium induced a significant decrease in GluA1 and GluA2 expression levels; a significant reduction in the expression of synaptophysin and GluN2A was observed only after EtOH withdrawal. Whole-cell patch-clamp recordings showed that incubation with EtOH for 7 days induced a significant decrease in spontaneous excitatory postsynaptic current (sEPSC) frequency in CA1 pyramidal cells of immature slices and a trend toward a decrease in sEPSC amplitude. Electron microscopy revealed a disorganization of neurotubuli in immature slices after chronic exposure to EtOH. CONCLUSIONS: These results indicate that prolonged incubation with EtOH and its subsequent withdrawal from the medium induce an impairment of excitatory synaptic transmission and possibly an incorrect formation of neuronal circuits in developing hippocampus in vitro, which is suggestive of mechanisms that may lead to mental retardation in fetal alcohol spectrum disorders.


Assuntos
Etanol/toxicidade , Hipocampo/efeitos dos fármacos , Hipocampo/crescimento & desenvolvimento , Transmissão Sináptica/efeitos dos fármacos , Consumo de Bebidas Alcoólicas/efeitos adversos , Animais , Animais Recém-Nascidos , Hipocampo/ultraestrutura , Técnicas de Cultura de Órgãos , Ratos , Ratos Wistar , Transmissão Sináptica/fisiologia
17.
Eur J Neurosci ; 42(9): 2699-706, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26354486

RESUMO

The selective vulnerability of substantia nigra pars compacta (SNc) dopaminergic (DA) neurons is an enigmatic trait of Parkinson's disease (PD), especially if compared to the remarkable resistance of closely related DA neurons in the neighboring ventral tegmental area (VTA). Overall evidence indicates that specific electrophysiological, metabolic and molecular factors underlie SNc vulnerability, although many pieces of the puzzle are still missing. In this respect, we recently demonstrated that 1-methyl-4-phenylpyridinium (MPP+), the active metabolite of the parkinsonizing toxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), alters the electrophysiological properties of SNc DA neurons in vitro by inhibiting the hyperpolarization-activated current (Ih). Here, we present an electrophysiological investigation of the functional role of Ih in the integration of synaptic inputs in identified SNc and VTA DA neurons, comparatively, in acute midbrain slices from TH-GFP mice. We show that pharmacological suppression of Ih increases the amplitude and decay time of excitatory postsynaptic potentials, leading to temporal summation of multiple excitatory potentials at somatic level. Importantly, these effects are quantitatively more evident in SNc DA neurons. We conclude that Ih regulates the responsiveness to excitatory synaptic transmission in SNc and VTA DA neurons differentially. Finally, we present the hypothesis that Ih loss of function may be linked to PD trigger mechanisms, such as mitochondrial failure and ATP depletion, and act in concert with SNc-specific synaptic connectivity to promote selective vulnerability.


Assuntos
Neurônios Dopaminérgicos/fisiologia , Potenciais Pós-Sinápticos Excitadores , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/fisiologia , Parte Compacta da Substância Negra/fisiologia , Somação de Potenciais Pós-Sinápticos , Área Tegmentar Ventral/fisiologia , Animais , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Feminino , Masculino , Camundongos , Camundongos Transgênicos , Parte Compacta da Substância Negra/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , Área Tegmentar Ventral/metabolismo
18.
Biochem Pharmacol ; 226: 116409, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38969300

RESUMO

Epilepsy is a central nervous system (CNS) disorder causing repeated seizures due to a transient excessive or synchronous alteration in the electrical activity of the brain. Several neurological disorders have been associated to gluten-related diseases (GRD), including epilepsy. However, the molecular mechanisms that associate GRD and epileptogenesis are still unknown. Our previous data have shown that the gliadin peptide 31-43 (p31-43) enhanced number and duration of seizures induced by kainate in mice and exacerbated CA3-kainate-induced neurotoxicity in organotypic hippocampal slices. Here, we investigated whether another important gliadin peptide p57-68 may exerts effects similar to p31-43 on kainate-induced neurotoxicity. We find that both peptides exacerbate kainate-induced damage in the CA3 region once simultaneously challenged. However, after pre-incubation, p31-43 additionally exacerbates neurotoxicity in the CA1 region, while p57-68 does not. These data suggested differential intracellular mechanisms activated by the peptides. Indeed, analysing intracellular signalling pathways we discover that p31-43 induces significant intracellular changes, including increased phosphorylation of Akt, Erk1/2, and p65, decreased p38 phosphorylation, and deacetylation of nuclear histone-3. Based on these observations, we demonstrate that p31-43 likely activates specific intracellular signaling pathways involved in neuronal excitability, inflammation, and epigenetic regulation, which may contribute to its exacerbation of kainate-induced neurotoxicity. In contrast, p57-68 appears to exert its effects through different mechanisms. Further research is necessary to elucidate the precise mechanisms by which these peptides influence neurotoxicity and understand their implications for neurological disorders.

19.
J Pharm Biomed Anal ; 241: 115974, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38277706

RESUMO

MDPHP is a synthetic cathinone (SC) belonging to α-pyrrolidinophenone derivatives. It is a central nervous system stimulant and may induce hallucinations, paranoia, tachycardia, hypertension, chest pain, and rhabdomyolysis. In literature, a few cases of intoxication have been reported. In the present study, 17 cases of MDPHP intake were described including the analytical findings and clinical manifestations. MDPHP was quantified by liquid chromatography-tandem mass spectrometry in blood (range 1.26-73.30 ng/mL) and urine (range 19.31-8769.64 ng/mL) samples. In three cases the presence of α-PHP was observed. In one case, MDPHP was the only detected substance. Concomitant use of MDPHP with other substances, particularly psychostimulants, was common and it was difficult to describe the peculiar clinical characteristics of this SC. Most of the symptoms overlapped those expected, some of them were unusual and all of them particularly severe thus inducing the research of NPS in laboratory tests. We demonstrated the presence of psychiatric, neurological, and respiratory symptoms, as well as the possible presence of rhabdomyolysis and cardiotoxicity associated with the use of MDPHP. ED admissions were also more frequent in patients with addiction problems. In some cases, MDPHP intake required intensive supportive care. A multidisciplinary approach, including specialist consultation, is recommended for patients showing challenging features. Moreover, we demonstrated that the adoption of advanced analytical techniques, i.e., liquid chromatography-tandem mass spectrometry, is necessary to detect these molecules. Further studies are needed to understand MDPHP intake patterns and associated symptoms. It is essential to raise awareness in addiction treatment centers and among potential users, especially young people, and chemsex addicted.


Assuntos
Estimulantes do Sistema Nervoso Central , Rabdomiólise , Humanos , Adolescente , Catinona Sintética , Espectrometria de Massas , Cromatografia Líquida
20.
Artigo em Inglês | MEDLINE | ID: mdl-38791766

RESUMO

INTRODUCTION: Our consensus statement aims to clarify the use of antidepressants and anxiolytics during breastfeeding amidst clinical uncertainty. Despite recent studies, potential harm to breastfed newborns from these medications remains a concern, leading to abrupt discontinuation of necessary treatments or exclusive formula feeding, depriving newborns of benefits from mother's milk. METHODS: A panel of 16 experts, representing eight scientific societies with a keen interest in postpartum depression, was convened. Utilizing the Nominal Group Technique and following a comprehensive literature review, a consensus statement on the pharmacological treatment of breastfeeding women with depressive disorders was achieved. RESULTS: Four key research areas were delineated: (1) The imperative to address depressive and anxiety disorders during lactation, pinpointing the risks linked to untreated maternal depression during this period. (2) The evaluation of the cumulative risk of unfavorable infant outcomes associated with exposure to antidepressants or anxiolytics. (3) The long-term impact on infants' cognitive development or behavior due to exposure to these medications during breastfeeding. (4) The assessment of pharmacological interventions for opioid abuse in lactating women diagnosed with depressive disorders. CONCLUSIONS: The ensuing recommendations were as follows: Recommendation 1: Depressive and anxiety disorders, as well as their pharmacological treatment, are not contraindications for breastfeeding. Recommendation 2: The Panel advocates for the continuation of medication that has demonstrated efficacy during pregnancy. If initiating an antidepressant during breastfeeding is necessary, drugs with a superior safety profile and substantial epidemiological data, such as SSRIs, should be favored and prescribed at the lowest effective dose. Recommendation 3: For the short-term alleviation of anxiety symptoms and sleep disturbances, the Panel determined that benzodiazepines can be administered during breastfeeding. Recommendation 4: The Panel advises against discontinuing opioid abuse treatment during breastfeeding. Recommendation 5: The Panel endorses collaboration among specialists (e.g., psychiatrists, pediatricians, toxicologists), promoting multidisciplinary care whenever feasible. Coordination with the general practitioner is also recommended.


Assuntos
Antidepressivos , Aleitamento Materno , Depressão Pós-Parto , Humanos , Feminino , Depressão Pós-Parto/tratamento farmacológico , Antidepressivos/uso terapêutico , Ansiolíticos/uso terapêutico , Recém-Nascido , Consenso
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