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1.
Membranes (Basel) ; 14(3)2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38535283

RESUMO

Among the most prevalent neurological disorders, epilepsy affects about 1% of the population worldwide. We previously found, using human epileptic tissues, that GABAergic neurotransmission impairment is a key mechanism that drives the pathological phenomena that ultimately lead to generation and recurrence of seizures. Using both a "microtransplantation technique" and synaptosomes preparations from drug-resistant temporal lobe epilepsies (TLEs), we used the technique of two-electrode voltage clamp to record GABA-evoked currents, focusing selectively on the synaptic "fast inhibition" mediated by low-affinity GABAA receptors. Here, we report that the use-dependent GABA current desensitization (i.e., GABA rundown, which is evoked by applying to the cells consecutive pulses of GABA, at high concentration), which is a distinguishing mark of TLE, is mainly dependent on a dysfunction that affects synaptic GABAA receptors. In addition, using the same approaches, we recorded a depolarized GABA reversal potential in synaptosomes samples from the human epileptic subicula of TLE patients. These results, which confirm previous experiments using total membranes, suggest an altered chloride homeostasis in the synaptic area. Finally, the lack of a Zn2+ block of GABA-evoked currents using the synaptosomes supports the enrichment of "synaptic fast inhibitory" GABAA receptors in this preparation. Altogether, our findings suggest a pathophysiological role of low-affinity GABAA receptors at the synapse, especially during the fast and repetitive GABA release underlying recurrent seizures.

2.
Curr Neuropharmacol ; 21(8): 1736-1754, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37143270

RESUMO

Despite the wide range of compounds currently available to treat epilepsy, there is still no drug that directly tackles the physiopathological mechanisms underlying its development. Indeed, antiseizure medications attempt to prevent seizures but are inefficacious in counteracting or rescuing the physiopathological phenomena that underlie their onset and recurrence, and hence do not cure epilepsy. Classically, the altered excitation/inhibition balance is postulated as the mechanism underlying epileptogenesis and seizure generation. This oversimplification, however, does not account for deficits in homeostatic plasticity resulting from either insufficient or excessive compensatory mechanisms in response to a change in network activity. In this respect, both neurodevelopmental epilepsies and those associated with neurodegeneration may share common underlying mechanisms that still need to be fully elucidated. The understanding of these molecular mechanisms shed light on the identification of new classes of drugs able not only to suppress seizures, but also to present potential antiepileptogenic effects or "disease-modifying" properties.


Assuntos
Anticonvulsivantes , Epilepsia , Animais , Humanos , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Epilepsia/tratamento farmacológico , Epilepsia/prevenção & controle , Modelos Animais de Doenças
4.
Inflamm Regen ; 43(1): 19, 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36895050

RESUMO

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a heterogeneous disease in terms of onset and progression rate. This may account for therapeutic clinical trial failure. Transgenic SOD1G93A mice on C57 or 129Sv background have a slow and fast disease progression rate, mimicking the variability observed in patients. Based on evidence inferring the active influence of skeletal muscle on ALS pathogenesis, we explored whether dysregulation in hindlimb skeletal muscle reflects the phenotypic difference between the two mouse models. METHODS: Ex vivo immunohistochemical, biochemical, and biomolecular methodologies, together with in vivo electrophysiology and in vitro approaches on primary cells, were used to afford a comparative and longitudinal analysis of gastrocnemius medialis between fast- and slow-progressing ALS mice. RESULTS: We reported that slow-progressing mice counteracted muscle denervation atrophy by increasing acetylcholine receptor clustering, enhancing evoked currents, and preserving compound muscle action potential. This matched with prompt and sustained myogenesis, likely triggered by an early inflammatory response switching the infiltrated macrophages towards a M2 pro-regenerative phenotype. Conversely, upon denervation, fast-progressing mice failed to promptly activate a compensatory muscle response, exhibiting a rapidly progressive deterioration of muscle force. CONCLUSIONS: Our findings further pinpoint the pivotal role of skeletal muscle in ALS, providing new insights into underestimated disease mechanisms occurring at the periphery and providing useful (diagnostic, prognostic, and mechanistic) information to facilitate the translation of cost-effective therapeutic strategies from the laboratory to the clinic.

5.
Antioxidants (Basel) ; 12(1)2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36670973

RESUMO

Down syndrome (DS) is the most frequent genetic cause of intellectual disability and is strongly associated with Alzheimer's disease (AD). Brain insulin resistance greatly contributes to AD development in the general population and previous studies from our group showed an early accumulation of insulin resistance markers in DS brain, already in childhood, and even before AD onset. Here we tested the effects promoted in Ts2Cje mice by the intranasal administration of the KYCCSRK peptide known to foster insulin signaling activation by directly interacting and activating the insulin receptor (IR) and the AKT protein. Therefore, the KYCCSRK peptide might represent a promising molecule to overcome insulin resistance. Our results show that KYCCSRK rescued insulin signaling activation, increased mitochondrial complexes levels (OXPHOS) and reduced oxidative stress levels in the brain of Ts2Cje mice. Moreover, we uncovered novel characteristics of the KYCCSRK peptide, including its efficacy in reducing DYRK1A (triplicated in DS) and BACE1 protein levels, which resulted in reduced AD-like neuropathology in Ts2Cje mice. Finally, the peptide elicited neuroprotective effects by ameliorating synaptic plasticity mechanisms that are altered in DS due to the imbalance between inhibitory vs. excitatory currents. Overall, our results represent a step forward in searching for new molecules useful to reduce intellectual disability and counteract AD development in DS.

6.
Life (Basel) ; 12(12)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36556407

RESUMO

Recently, the potential use of phytocannabinoids (pCBs) to treat different pathological conditions has attracted great attention in the scientific community. Among the different pCBs, cannabidiol (CBD) has showed interesting biological properties, making it a promising molecule with a high security profile that has been approved for treatment as an add-on therapy in patients afflicted by severe pharmaco-resistant epilepsy, including Dravet syndrome (DS), Lennox-Gastaut syndrome (LGS) and tuberous sclerosis complex (TSC). CBD is pharmacologically considered a "dirty drug", since it has the capacity to bind different targets and to activate several cellular pathways. GABAergic impairment is one of the key processes during the epileptogenesis period able to induce a generalized hyperexcitability of the central nervous system (CNS), leading to epileptic seizures. Here, by using the microtransplantation of human brain membranes approach in Xenopus oocytes and electrophysiological recordings, we confirm the ability of CBD to modulate GABAergic neurotransmission in human cerebral tissues obtained from patients afflicted by different forms of pharmaco-resistant epilepsies, such as DS, TSC, focal cortical dysplasia (FCD) type IIb and temporal lobe epilepsy (TLE). Furthermore, using cDNAs encoding for human GABAA receptor subunits, we found that α1ß2 receptors are still affected by CBD, while classical benzodiazepine lost its efficacy as expected.

7.
Sci Rep ; 12(1): 17956, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36289354

RESUMO

Gangliogliomas (GGs) are low-grade brain tumours that cause intractable focal epilepsy in children and adults. In GG, as in epileptogenic focal malformations (i.e., tuberous sclerosis complex, TSC), there is evidence of sustained neuroinflammation with involvement of the pro-inflammatory cytokine IL-1ß. On the other hand, anti-inflammatory mediators are less studied but bear relevance for understanding seizure mechanisms. Therefore, we investigated the effect of the key anti-inflammatory cytokine IL-10 on GABAergic neurotransmission in GG. We assessed the IL-10 dependent signaling by transcriptomic analysis, immunohistochemistry and performed voltage-clamp recordings on Xenopus oocytes microtransplanted with cell membranes from brain specimens, to overcome the limited availability of acute GG slices. We report that IL-10-related mRNAs were up-regulated in GG and slightly in TSC. Moreover, we found IL-10 receptors are expressed by neurons and astroglia. Furthermore, GABA currents were potentiated significantly by IL-10 in GG. This effect was time and dose-dependent and inhibited by blockade of IL-10 signaling. Notably, in the same tissue, IL-1ß reduced GABA current amplitude and prevented the IL-10 effect. These results suggest that in epileptogenic tissue, pro-inflammatory mechanisms of hyperexcitability prevail over key anti-inflammatory pathways enhancing GABAergic inhibition. Hence, boosting the effects of specific anti-inflammatory molecules could resolve inflammation and reduce intractable seizures.


Assuntos
Epilepsia Resistente a Medicamentos , Ganglioglioma , Adulto , Criança , Humanos , Ácido gama-Aminobutírico , Ganglioglioma/complicações , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Receptores de GABA-A/metabolismo , Receptores Imunológicos/metabolismo , Receptores de Interleucina-10/metabolismo
8.
Front Pharmacol ; 13: 982434, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36052140

RESUMO

Background: 3,4-diaminopyridine (3,4-DAP) can lead to clinical and electrophysiological improvement in myasthenic syndrome; it may thus represent a valuable therapeutic option for patients intolerant to pyridostigmine. Objective: to assess 3,4-diaminopyridine (3,4-DAP) effects and tolerability in patients with anti-AChR myasthenia gravis. Method: Effects were monitored electrophysiologically by repetitive nerve stimulation (RNS) and by standardized clinical testing (QMG score) before and after a single dose administration of 3,4-DAP 10 mg per os in 15 patients. Patients were divided according to their Myasthenia Gravis Foundation of America (MGFA) class into mild and severe. Results: No significant side effects were found, apart from transient paresthesia. 3,4-DAP had a significant effect on the QMG score (p = 0.0251), on repetitive nerve stimulation (p = 0.0251), and on the forced vital capacity (p = 0.03), thus indicating that it may reduce the level of disability and the decremental muscle response. When the patients were divided according to the MGFA classification, 3,4-DAP showed a positive effect in the severe group, either for the QMG score (p = 0.031) or for the RNS decrement (p = 0.031). No significant difference was observed in any of the outcome measures within the mild group (p > 0.05). A direct effect of 3,4-DAP on nicotinic ACh receptors (nAChRs) was excluded since human nAChRs reconstituted in an expression system, which were not affected by 3,4-DAP application. Conclusion: Our results suggest that 3,4-DAP may be a useful add-on therapy, especially in most severe patients or when immunosuppressive treatment has not yet reached its full effect or when significant side-effects are associated with anticholinesterase.

9.
Biomolecules ; 12(6)2022 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-35740883

RESUMO

Recently, the endocannabinoid system has attracted growing attention from the scientific community for its involvement in homeostatic and pathological processes as they pertains to human physiology. Among the constituents of the endocannabinoid system, the molecule palmitoyl ethanolamide has particularly been studied for its ability to reduce several inflammatory processes involving the central nervous system. Here, we reviewed published literature and summarized the main targets of the palmitoyl ethanolamide, along with its unique possible mechanisms for restoring correct functioning of the central nervous system. Moreover, we have highlighted a less-known characteristic of palmitoyl ethanolamide, namely its ability to modulate the function of the neuromuscular junction by binding to acetylcholine receptors in different experimental conditions. Indeed, there are several studies that have highlighted how ultra-micronized palmitoyl ethanolamide is an interesting nutraceutical support for the treatment of pathological neuromuscular conditions, specifically when the normal activity of the acetylcholine receptor is altered. Although further multicentric clinical trials are needed to confirm the efficacy of ultra-micronized palmitoyl ethanolamide in improving symptoms of neuromuscular diseases, all the literature reviewed here strongly supports the ability of this endocannabinoid-like molecule to modulate the acetylcholine receptors thus resulting as a valid support for the treatment of human neuromuscular diseases.


Assuntos
Endocanabinoides , Doenças Neuromusculares , Receptores Colinérgicos , Endocanabinoides/metabolismo , Humanos , Doenças Neuromusculares/tratamento farmacológico
10.
Brain Sci ; 12(6)2022 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-35741692

RESUMO

Focal cortical dysplasia (FCD) type II is an epileptogenic malformation of the neocortex, as well as a leading cause of drug-resistant focal epilepsy in children and young adults. The synaptic dysfunctions leading to intractable seizures in this disease appear to have a tight relationship with the immaturity of GABAergic neurotransmission. The likely outcome would include hyperpolarizing responses upon activation of GABAARs. In addition, it is well-established that neuroinflammation plays a relevant role in the pathogenesis of FCD type II. Here, we investigated whether IL-1ß, a prototypical pro-inflammatory cytokine, can influence GABAergic neurotransmission in FCD brain tissues. To this purpose, we carried out electrophysiological recordings on Xenopus oocytes transplanted with human tissues and performed a transcriptomics analysis. We found that IL-1ß decreases the GABA currents amplitude in tissue samples from adult individuals, while it potentiates GABA responses in samples from pediatric cases. Interestingly, these cases of pediatric FCD were characterized by a more depolarized EGABA and an altered transcriptomics profile, that revealed an up-regulation of chloride cotransporter NKCC1 and IL-1ß. Altogether, these results suggest that the neuroinflammatory processes and altered chloride homeostasis can contribute together to increase the brain excitability underlying the occurrence of seizures in these children.

11.
J Alzheimers Dis ; 88(3): 903-931, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35694930

RESUMO

BACKGROUND: Patients with amnesic mild cognitive impairment due to Alzheimer's disease (ADMCI) typically show a "slowing" of cortical resting-state eyes-closed electroencephalographic (rsEEG) rhythms. Some of them also show subclinical, non-convulsive, and epileptiform EEG activity (EEA) with an unclear relationship with that "slowing." OBJECTIVE: Here we tested the hypothesis that the "slowing" of rsEEG rhythms is related to EEA in ADMCI patients. METHODS: Clinical and instrumental datasets in 62 ADMCI patients and 38 normal elderly (Nold) subjects were available in a national archive. No participant had received a clinical diagnosis of epilepsy. The eLORETA freeware estimated rsEEG cortical sources. The area under the receiver operating characteristic curve (AUROCC) indexed the accuracy of eLORETA solutions in the classification between ADMCI-EEA and ADMCI-noEEA individuals. RESULTS: EEA was observed in 15% (N = 8) of the ADMCI patients. The ADMCI-EEA group showed: 1) more abnormal Aß42 levels in the cerebrospinal fluid as compared to the ADMCI-noEEA group and 2) higher temporal and occipital delta (<4 Hz) rsEEG source activities as compared to the ADMCI-noEEA and Nold groups. Those source activities showed moderate accuracy (AUROCC = 0.70-0.75) in the discrimination between ADMCI-noEEA versus ADMCI-EEA individuals. CONCLUSION: It can be speculated that in ADMCI-EEA patients, AD-related amyloid neuropathology may be related to an over-excitation in neurophysiological low-frequency (delta) oscillatory mechanisms underpinning cortical arousal and quiet vigilance.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Idoso , Doença de Alzheimer/patologia , Córtex Cerebral/patologia , Disfunção Cognitiva/diagnóstico , Ritmo Delta , Eletroencefalografia , Humanos , Descanso/fisiologia
12.
Biomedicines ; 10(5)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35625812

RESUMO

Mutations in SCN1A gene, encoding the voltage-gated sodium channel (VGSC) NaV1.1, are widely recognized as a leading cause of genetic febrile seizures (FS), due to the decrease in the Na+ current density, mainly affecting the inhibitory neuronal transmission. Here, we generated induced pluripotent stem cells (iPSCs)-derived neurons (idNs) from a patient belonging to a genetically well-characterized Italian family, carrying the c.434T > C mutation in SCN1A gene (hereafter SCN1AM145T). A side-by-side comparison of diseased and healthy idNs revealed an overall maturation delay of SCN1AM145T cells. Membranes isolated from both diseased and control idNs were injected into Xenopus oocytes and both GABA and AMPA currents were successfully recorded. Patch-clamp measurements on idNs revealed depolarized action potential for SCN1AM145T, suggesting a reduced excitability. Expression analyses of VGSCs and chloride co-transporters NKCC1 and KCC2 showed a cellular "dysmaturity" of mutated idNs, strengthened by the high expression of SCN3A, a more fetal-like VGSC isoform, and a high NKCC1/KCC2 ratio, in mutated cells. Overall, we provide strong evidence for an intrinsic cellular immaturity, underscoring the role of mutant NaV1.1 in the development of FS. Furthermore, our data are strengthening previous findings obtained using transfected cells and recordings on human slices, demonstrating that diseased idNs represent a powerful tool for personalized therapy and ex vivo drug screening for human epileptic disorders.

13.
FASEB J ; 36(3): e22203, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35188290

RESUMO

Epilepsy is a severe neurological disease manifested by spontaneous recurrent seizures due to abnormal hyper-synchronization of neuronal activity. Epilepsy affects about 1% of the population and up to 40% of patients experience seizures that are resistant to currently available drugs, thus highlighting an urgent need for novel treatments. In this regard, anti-inflammatory drugs emerged as potential therapeutic candidates. In particular, specific molecules apt to resolve the neuroinflammatory response occurring in acquired epilepsies have been proven to counteract seizures in experimental models, and humans. One candidate investigational molecule has been recently identified as the lipid mediator n-3 docosapentaenoic acid-derived protectin D1 (PD1n-3DPA ) which significantly reduced seizures, cell loss, and cognitive deficit in a mouse model of acquired epilepsy. However, the mechanisms that mediate the PD1n-3DPA effect remain elusive. We here addressed whether PD1n-3DPA has direct effects on neuronal activity independent of its anti-inflammatory action. We incubated, therefore, hippocampal slices with PD1n-3DPA and investigated its effect on excitatory and inhibitory synaptic inputs to the CA1 pyramidal neurons. We demonstrate that inhibitory drive onto the perisomatic region of the pyramidal neurons is increased by PD1n-3DPA , and this effect is mediated by pertussis toxin-sensitive G-protein coupled receptors. Our data indicate that PD1n-3DPA acts directly on inhibitory transmission, most likely at the presynaptic site of inhibitory synapses as also supported by Xenopus oocytes and immunohistochemical experiments. Thus, in addition to its anti-inflammatory effects, PD1n-3DPA anti-seizure and neuroprotective effects may be mediated by its direct action on neuronal excitability by modulating their synaptic inputs.


Assuntos
Região CA1 Hipocampal/metabolismo , Ácidos Docosa-Hexaenoicos/farmacologia , Potenciais Pós-Sinápticos Inibidores , Neurônios/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Região CA1 Hipocampal/citologia , Região CA1 Hipocampal/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Xenopus
14.
Neuropathol Appl Neurobiol ; 48(1): e12758, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34388852

RESUMO

AIMS: The causes of distinct patterns of reduced cortical thickness in the common human epilepsies, detectable on neuroimaging and with important clinical consequences, are unknown. We investigated the underlying mechanisms of cortical thinning using a systems-level analysis. METHODS: Imaging-based cortical structural maps from a large-scale epilepsy neuroimaging study were overlaid with highly spatially resolved human brain gene expression data from the Allen Human Brain Atlas. Cell-type deconvolution, differential expression analysis and cell-type enrichment analyses were used to identify differences in cell-type distribution. These differences were followed up in post-mortem brain tissue from humans with epilepsy using Iba1 immunolabelling. Furthermore, to investigate a causal effect in cortical thinning, cell-type-specific depletion was used in a murine model of acquired epilepsy. RESULTS: We identified elevated fractions of microglia and endothelial cells in regions of reduced cortical thickness. Differentially expressed genes showed enrichment for microglial markers and, in particular, activated microglial states. Analysis of post-mortem brain tissue from humans with epilepsy confirmed excess activated microglia. In the murine model, transient depletion of activated microglia during the early phase of the disease development prevented cortical thinning and neuronal cell loss in the temporal cortex. Although the development of chronic seizures was unaffected, the epileptic mice with early depletion of activated microglia did not develop deficits in a non-spatial memory test seen in epileptic mice not depleted of microglia. CONCLUSIONS: These convergent data strongly implicate activated microglia in cortical thinning, representing a new dimension for concern and disease modification in the epilepsies, potentially distinct from seizure control.


Assuntos
Epilepsia , Microglia , Animais , Encéfalo , Células Endoteliais , Epilepsia/metabolismo , Camundongos , Microglia/metabolismo , Convulsões
15.
Int J Mol Sci ; 22(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34206089

RESUMO

Amyloid-ß (Aß) 1-40 and 1-42 peptides are key mediators of synaptic and cognitive dysfunction in Alzheimer's disease (AD). Whereas in AD, Aß is found to act as a pro-epileptogenic factor even before plaque formation, amyloid pathology has been detected among patients with epilepsy with increased risk of developing AD. Among Aß aggregated species, soluble oligomers are suggested to be responsible for most of Aß's toxic effects. Aß oligomers exert extracellular and intracellular toxicity through different mechanisms, including interaction with membrane receptors and the formation of ion-permeable channels in cellular membranes. These damages, linked to an unbalance between excitatory and inhibitory neurotransmission, often result in neuronal hyperexcitability and neural circuit dysfunction, which in turn increase Aß deposition and facilitate neurodegeneration, resulting in an Aß-driven vicious loop. In this review, we summarize the most representative literature on the effects that oligomeric Aß induces on synaptic dysfunction and network disorganization.


Assuntos
Doença de Alzheimer/genética , Peptídeos beta-Amiloides/genética , Sinapses/genética , Transmissão Sináptica/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/efeitos adversos , Peptídeos beta-Amiloides/ultraestrutura , Proteínas Amiloidogênicas/efeitos adversos , Proteínas Amiloidogênicas/genética , Animais , Humanos , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Multimerização Proteica/genética , Sinapses/metabolismo
16.
Brain Sci ; 11(4)2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33808090

RESUMO

GABAA receptors-(Rs) are fundamental for the maintenance of an efficient inhibitory function in the central nervous system (CNS). Their dysfunction is associated with a wide range of CNS disorders, many of which characterized by seizures and epilepsy. Recently, an increased use-dependent desensitization due to a repetitive GABA stimulation (GABAA current rundown) of GABAARs has been associated with drug-resistant temporal lobe epilepsy (TLE). Here, we aimed to investigate the molecular determinants of GABAA current rundown with two different heterologous expression systems (Xenopus oocytes and human embryonic kidney cells; HEK) which allowed us to manipulate receptor stoichiometry and to study the GABAA current rundown on different GABAAR configurations. To this purpose, we performed electrophysiology experiments using two-electrode voltage clamp in oocytes and confirming part of our results in HEK. We found that different degrees of GABAA current rundown can be associated with the expression of different GABAAR ß-subunits reaching the maximum current decrease when functional α1ß2 receptors are expressed. Furthermore, the blockade of phosphatases can prevent the current rundown observed in α1ß2 GABAARs. Since GABAAR represents one important therapeutic target in the treatment of human epilepsy, our results could open new perspectives on the therapeutic management of drug-resistant patients showing a GABAergic impairment.

17.
Front Neurol ; 11: 514136, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33192962

RESUMO

In the present exploratory and retrospective study, we hypothesized that cortical sources of resting state eyes-closed electroencephalographic (rsEEG) rhythms might be more abnormal in patients with epileptiform EEG activity (spike-sharp wave discharges, giant spikes) and amnesic mild cognitive impairment not due to Alzheimer's disease (noADMCI-EEA) than matched noADMCI patients without EEA (noADMCI-noEEA). Clinical, neuroimaging, neuropsychological, and rsEEG data in 32 noADMCI and 30 normal elderly (Nold) subjects were available in a national archive. Age, gender, and education were carefully matched among them. No subject had received a clinical diagnosis of epilepsy. Individual alpha frequency peak (IAF) was used to determine the delta, theta, and alpha frequency bands of rsEEG rhythms. Fixed beta and gamma bands were also considered. Regional rsEEG cortical sources were estimated by eLORETA freeware. Area under receiver operating characteristic (AUROC) curves indexed the accuracy of eLORETA solutions in the classification between noADMCI-EEA and noADMCI-noEEA individuals. As novel findings, EEA was observed in 41% of noADMCI patients. Furthermore, these noADMCI-EEA patients showed higher temporal delta source activities as compared to noADMCI-no EEA patients and Nold subjects. Those activities discriminated individuals of the two NoADMCI groups with an accuracy of about 70%. The significant percentage of noADMCI-EEA patients showing EEA and marked abnormalities in temporal rsEEG rhythms at delta frequencies suggest a substantial role of underlying neural hypersynchronization mechanisms in their brain dysfunctions.

19.
Ann Clin Transl Neurol ; 7(9): 1726-1731, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32761786

RESUMO

We compared GABAergic function and neuronal excitability in the hippocampal tissue of seven sporadic MTLE patients with a patient carrying a SCN1A loss-of-function mutation. All had excellent outcome from anterior temporal lobectomy, and neuropathological study always showed characteristic hippocampal sclerosis (Hs). Compared to MTLE patients, there was a more severe impairment of GABAergic transmission, due to the lower GABAergic activity related to the NaV 1.1 loss-of-function, in addition to the typical GABA-current rundown, a hallmark of sporadic MTLE. Our results give evidence that a pharmacological rescuing of the GABAergic dysfunction may represent a promising strategy for the treatment of these patients.


Assuntos
Epilepsia do Lobo Temporal , Hipocampo , Canal de Sódio Disparado por Voltagem NAV1.1/genética , Ácido gama-Aminobutírico/metabolismo , Adulto , Lobectomia Temporal Anterior , Epilepsia do Lobo Temporal/genética , Epilepsia do Lobo Temporal/metabolismo , Epilepsia do Lobo Temporal/patologia , Epilepsia do Lobo Temporal/fisiopatologia , Hipocampo/metabolismo , Hipocampo/patologia , Hipocampo/fisiopatologia , Humanos , Mutação com Perda de Função , Masculino , Técnicas de Patch-Clamp , Esclerose/patologia
20.
Cells ; 9(5)2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32397320

RESUMO

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease with no recognized clinical prognostic factor. Creatinine kinase (CK) increase in these patients is already described with conflicting results on prognosis and survival. In 126 ALS patients who were fast or slow disease progressors, CK levels were assayed for 16 months every 4 months in an observational case-control cohort study with prospective data collection conducted in Italy. CK was also measured at baseline in 88 CIDP patients with secondary axonal damage and in two mouse strains (129SvHSD and C57-BL) carrying the same SOD1G93A transgene expression but showing a fast (129Sv-SOD1G93A) and slow (C57-SOD1G93A) ALS progression rate. Higher CK was found in ALS slow progressors compared to fast progressors in T1, T2, T3, and T4, with a correlation with Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) scores. Higher CK was found in spinal compared to bulbar-onset patients. Transgenic and non-transgenic C57BL mice showed higher CK levels compared to 129SvHSD strain. At baseline mean CK was higher in ALS compared to CIDP. CK can predict the disease progression, with slow progressors associated with higher levels and fast progressors to lower levels, in both ALS patients and mice. CK is higher in ALS patients compared to patients with CIDP with secondary axonal damage; the higher levels of CK in slow progressors patients, but also in C57BL transgenic and non-transgenic mice designs CK as a predisposing factor for disease rate progression.


Assuntos
Esclerose Lateral Amiotrófica/enzimologia , Esclerose Lateral Amiotrófica/patologia , Creatina Quinase/metabolismo , Progressão da Doença , Adulto , Idoso , Idoso de 80 Anos ou mais , Esclerose Lateral Amiotrófica/sangue , Animais , Creatina Quinase/sangue , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pessoa de Meia-Idade , Mioglobina/metabolismo , Fatores de Tempo
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