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1.
Saudi Pharm J ; 29(5): 418-426, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34135667

RESUMO

OBJECTIVES: Epilepsy is a neurological disease characterized by sudden, abnormal, and hyper- discharges in the central nervous system (CNS). Valproic acid (VPA) is commonly used as a broad-spectrum antiepileptic therapeutic. However, in many cases, patients develop resistance to VPA treatment due to overwhelming oxidative stress, which in turn might be a major catalyst for disease progression. Therefore, antioxidants can potentially become therapeutic agents by counteracting reactive oxygen species (ROS)-mediated damage. The present study is aimed to evaluate the potential antiepileptic effect of astaxanthin (ASTA) in pentylenetetrazol (PTZ) induced epileptic model rats that are chronically treated with VPA for 8 weeks. METHOD: Fifty-male Wistar rats were randomly divided into five groups: Non-PTZ group, PTZ, PTZ/VPA, PTZ/ASTA, and PTZ/VPA/ASTA treated groups. RESULTS: PTZ/VPA treated group showed a neuroprotective effect with improvement in antioxidant levels, behavioral test, and histopathological changes induced by PTZ. VPA also exhibited an anti-inflammatory effect as its treatment resulted in the reduction of tumor necrosis factor-α (TNF-α). ASTA exhibited an anticonvulsant effect and enhanced anti-inflammatory effect as compared to VPA. During the combined therapy, ASTA potentiated the antiepileptic effect of the VPA by reducing the oxidative stress and TNF-α as well as increased the glutathione (GSH) levels. Also, there were substantial improvements in the behavioral and histopathological changes in the VPA/ASTA treated group as compared to the VPA treated group. CONCLUSION: ASTA could have an antiepileptic and anti-inflammatory effect by reducing ROS generation. Therefore, co-administration of both the therapeutics (VPA/ASTA) has a synergistic effect in treating epilepsy and could potentially minimize recurrence and/or exacerbation of seizures.

2.
Epilepsy Behav Rep ; 19: 100547, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35733834

RESUMO

Copy number variations (CNVs) have been related to developmental and epileptic encephalopathy (DEE). The 2q24.3 region includes a cluster of genes for voltage-gated sodium channels (SCN) and CNVs in this region cause DEE. However, the long-term course of DEE with a 2q24.3 duplication has not been described. A 20-year-old female developed epileptic encephalopathy in early infancy that was resistant to various antiseizure medications. Her seizures disappeared after starting vitamin B6 therapy. Therefore, her epilepsy was considered pyridoxine-dependent epilepsy. At 16 years old, whole exome sequencing revealed a 2q24.3 microduplication including SCN1A, SCN2A, SCN3A, SCN7A, and SCN9A. Quantitative PCR detected an increased copy number of 1.3 Mb on 2q24.3 involving these genes, but no gene mutation accounting for pyridoxine-dependent epilepsy. Considering that with this duplication she was reported to be seizure-free after infancy, she was able to be off antiseizure medications including vitamin B6. Our case involvingdrug-resistant epilepsy in early infancy had no recurrent seizures during long-term follow up. Detecting CNVs using whole exome sequencing data was useful to identify a 2q24.3 duplication unassociated with pyridoxine-dependent epilepsy, leading to cessation of unnecessary medications.

3.
eNeurologicalSci ; 22: 100298, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33313428

RESUMO

BACKGROUND: Angelman syndrome (AS) is neurodevelopmental disorder, causal gene of which is maternally expressed UBE3A. A majority of patients results from the large deletion of relevant chromosome which includes GABAA receptor subunit genes (GABARs) as well as UBE3A (AS Del). We previously reported aberrantly desynchronized primary somatosensory response in AS Del by using magnetoencephalography. The purpose of this study is to estimate cortical and subcortical involvement in the deficit of primary somatosensory processing in AS. METHODS: We analyzed short-latency somatosensory-evoked potentials (SSEPs) in 8 patients with AS Del. SSEPs were recorded on a 4-channel system comprising of two cortical electrodes which were placed on the frontal and centro-parietal areas. The peak and onset latency of each component were measured to compare latency and interval times. RESULTS: The first-cortical peak latency (N20, P20), and N13-N20 peak interval times were significantly prolonged in AS Del compared to healthy controls. In contrast, there was no difference in latencies between subcortical components up to N20 onset or for N11-N20 onset interval times. CONCLUSION: Highly desynchronized first-cortical SSEP components and normal latencies of subcortical components indicated cortical dysfunction rather than impairment of afferent pathways in AS Del patients, which might be attributed to GABAergic dysfunction due to loss of UBE3A function and heterozygosity of GABARs.

4.
DNA Repair (Amst) ; 95: 102940, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32795962

RESUMO

Breast carcinoma is one of the most common malignancies in women. Previous studies have reported that 500 µM valproic acid can sensitize breast tumor cells to the anti-neoplastic agent hydroxyurea. However, the dose requirements for valproic acid is highly variable due to the wide inter-individuals clinical characteristics. High therapeutic dose of valproic acid required to induce anti-tumor activity in solid tumor was associated with increased adverse effects. There are attempts to locate suitably high-efficient low-toxicity valproic acid derivatives. We demonstrated that lower dose of 2-hexyl-4-pentynoic acid (HPTA; 15 µM) has similar effects as 500 µM VPA in inhibiting breast cancer cell growth and sensitizing the tumor cells to hydroxyurea on MCF7 cells, EUFA423 cells, MCF7 cells with defective RPA2-p gene and primary culture cells derived from tissue-transformed breast tumor cells. We discovered HPTA resulted in more DNA double-strand breaks, the homologous recombination was inhibited through the interference of the hyperphosphorylation of replication protein A2 and recombinase Rad51. Our data postulate that HPTA may be a potential novel sensitizer to hydroxyurea in the treatment of breast carcinoma.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Quebras de DNA de Cadeia Dupla , Ácidos Graxos Insaturados/farmacologia , Rad51 Recombinase/metabolismo , Reparo de DNA por Recombinação , Proteína de Replicação A/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , DNA de Neoplasias/metabolismo , Ácidos Graxos Insaturados/uso terapêutico , Feminino , Humanos , Hidroxiureia/uso terapêutico , Células MCF-7 , Fosforilação , Processamento de Proteína Pós-Traducional
5.
Epilepsy Behav Rep ; 14: 100373, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32695984

RESUMO

We observed that cannabidiol supplements were highly effective in treating an infant boy with drug-resistant early infantile epileptic encephalopathy, eliminating his intractable tonic seizures. The infant began suffering clusters of brief tonic seizures from birth at 39 weeks gestation. EEG showed burst-suppression and seizures could not be controlled by trials of phenobarbital, zonisamide, vitamin B6, clobazam, levetiracetam, topiramate, phenytoin, valproate, high-dose phenobarbital, and ACTH therapy. The boy was discharged from hospital at 130 days of age still averaging tonic seizures 20-30 times per day. We started him on a cannabidiol supplement on day 207, increasing the dosage to 18 mg/kg/d on day 219. His seizures reduced in frequency and completely disappeared by day 234. These effects were maintained, with improved EEG background, even after his other medications were discontinued. Cannabidiol's effectiveness in treating drug-resistant epilepsy has been confirmed in large-scale clinical trials in Europe and the United States; however, no such trials have been run in Asia. In addition, no reports to date have documented its efficacy in an infant as young as six months of age. This important case suggests that high-dose artisanal cannabidiol may effectively treat drug-resistant epilepsy in patients without access to pharmaceutical-grade CBD.

6.
Epilepsy Behav Rep ; 14: 100384, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33089135

RESUMO

Gorlin-Goltz syndrome, also known as nevoid basal cell carcinoma syndrome, is a genetic disorder with several neurological, cutaneous and skeletal manifestations. Epilepsy has been previously reported as a finding in Gorlin-Goltz syndrome but remains ill-described in the context of this disease. We report two new patients with Gorlin-Goltz syndrome featuring epilepsy and review the existing literature on the topic.

7.
MethodsX ; 7: 101055, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32995308

RESUMO

Evidence of the involvement of epigenetics in pathologies such as cancer, diabetes, and neurodegeneration has increased global interest in epigenetic modifications. For nearly thirty years, it has been known that cancer cells exhibit abnormal DNA methylation patterns. In contrast, the large-scale analysis of histone post-translational modifications (hPTMs) has lagged behind because classically, histone modification analysis has relied on site specific antibody-based techniques. Mass spectrometry (MS) is a technique that holds the promise to picture the histone code comprehensively in a single experiment. Therefore, we developed an MS-based method that is capable of tracking all possible hPTMs in an untargeted approach. In this way, trends in single and combinatorial hPTMs can be reported and enable prediction of the epigenetic toxicity of compounds. Moreover, this method is based on the use of human cells to provide preliminary data, thereby omitting the need to sacrifice laboratory animals. Improving the workflow and the user-friendliness in order to become a high throughput, easily applicable, toxicological screening assay is an ongoing effort. Still, this novel toxicoepigenetic assay and the data it generates holds great potential for, among others, pharmaceutical industry, food science, clinical diagnostics and, environmental toxicity screening. •There is a growing interest in epigenetic modifications, and more specifically in histone post-translational modifications (hPTMs).•We describe an MS-based workflow that is capable of tracking all possible hPTMs in an untargeted approach that makes use of human cells.•Improving the workflow and the user-friendliness in order to become a high throughput, easily applicable, toxicological screening assay is an ongoing effort.

8.
Epilepsy Behav Rep ; 12: 100342, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31799506

RESUMO

Patients with mutations in the POLG-1 gene often are afflicted with drug-resistant seizures at an early age and have an increased risk of valproic acid-induced acute liver failure. Severe valproate hepatotoxicity most commonly arises in children within the first 3 months of treatment with an overall estimated incidence of 1 in 40,000 treated patients. Due to high mortality rates among transplanted children, many experts consider valproic acid-induced acute liver failure in patients with mitochondrial disorders to be a contraindication to liver transplant. We report the successful use of liver transplantation in a young man with valproic acid-associated acute liver failure harboring a previously unrecognized POLG-1 mutation.

9.
Epilepsy Behav Case Rep ; 11: 47-51, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30671345

RESUMO

Ictal syncope is a rare phenomenon that occurs in association with 0.002-0.4% of seizures. In the absence of other symptoms, seizures presenting with syncope may be challenging to diagnose. We report a case of a previously healthy male who developed recurrent episodes of syncope with postictal confusion and was later diagnosed with temporal seizures. The patient was successfully treated with anti-seizure drugs and placement of a cardiac pacemaker. In a systematic review of literature, we summarize the clinical characteristics of patients with ictal asystole and isolated syncope. Seizures should be considered in patients with syncope of uncertain etiology.

10.
Pract Lab Med ; 10: 15-20, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29234708

RESUMO

We present a simple and fast high-performance liquid chromatography method with fluorescence detection for the determination of the antiepileptic drug perampanel in human plasma. The chromatographic separation was performed on a Kinetex PFP (100 × 2.6 mm, 4.6 µm) column, using a mobile phase of sodium acetate 0.03 M pH 3.7 and acetonitrile (40/60, v/v), at a flow rate of 0.8 mL/min. Total chromatography time for each run was 5 min. Sample preparation (250 µL) involved only one simple precipitation step by acetonitrile spiked with mirtazapine as internal standard. The method was validated over a concentration range of 20-1000 ng/mL and successfully applied to measure perampanel concentrations in plasma samples obtained from patients with epilepsy. This assay combines the high specificity of fluorescence detection with a very simple and fast sample pretreatment and can offer real advantages over existing methods in terms of simplicity and transferability to a therapeutic drug monitoring setting.

11.
Cell Mol Gastroenterol Hepatol ; 6(4): 477-493.e1, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30364784

RESUMO

Background & Aims: Microvillus inclusion disease (MVID) is a congenital intestinal malabsorption disorder caused by defective apical vesicular transport. Existing cellular models do not fully recapitulate this heterogeneous pathology. The aim of this study was to characterize 3-dimensional intestinal organoids that continuously generate polarized absorptive cells as an accessible and relevant model to investigate MVID. Methods: Intestinal organoids from Munc18-2/Stxbp2-null mice that are deficient for apical vesicular transport were subjected to enterocyte-specific differentiation protocols. Lentiviral rescue experiments were performed using human MUNC18-2 variants. Apical trafficking and microvillus formation were characterized by confocal and transmission electron microscopy. Spinning disc time-lapse microscopy was used to document the lifecycle of microvillus inclusions. Results: Loss of Munc18-2/Stxbp2 recapitulated the pathologic features observed in patients with MUNC18-2 deficiency. The defects were fully restored by transgenic wild-type human MUNC18-2 protein, but not the patient variant (P477L). Importantly, we discovered that the MVID phenotype was correlated with the degree of enterocyte differentiation: secretory vesicles accumulated already in crypt progenitors, while differentiated enterocytes showed an apical tubulovesicular network and enlarged lysosomes. Upon prolonged enterocyte differentiation, cytoplasmic F-actin-positive foci were observed that further progressed into classic microvillus inclusions. Time-lapse microscopy showed their dynamic formation by intracellular maturation or invagination of the apical or basolateral plasma membrane. Conclusions: We show that prolonged enterocyte-specific differentiation is required to recapitulate the entire spectrum of MVID. Primary organoids can provide a powerful model for this heterogeneous pathology. Formation of microvillus inclusions from multiple membrane sources showed an unexpected dynamic of the enterocyte brush border.


Assuntos
Diferenciação Celular , Enterócitos/patologia , Intestinos/patologia , Síndromes de Malabsorção/metabolismo , Microvilosidades/patologia , Mucolipidoses/metabolismo , Proteínas Munc18/deficiência , Proteínas Munc18/metabolismo , Organoides/metabolismo , Actinas/metabolismo , Animais , Núcleo Celular/metabolismo , Enterócitos/metabolismo , Humanos , Lisossomos/metabolismo , Síndromes de Malabsorção/patologia , Camundongos Knockout , Microvilosidades/metabolismo , Microvilosidades/ultraestrutura , Mucolipidoses/patologia , Organoides/patologia , Organoides/ultraestrutura
12.
JACC Basic Transl Sci ; 3(5): 704-715, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30456341

RESUMO

Chemical modifications to nucleosomal DNA and histone tails greatly influence transcription of adjacent and distant genes, a mode of gene regulation referred to as epigenetic control. Here, the authors summarize recent findings that have illustrated crucial roles for epigenetic regulatory enzymes and reader proteins in the control of cardiac fibrosis. Particular emphasis is placed on epigenetic regulation of stress-induced inflammation and fibroblast activation in the heart. The potential of developing innovative small molecule "epigenetic therapies" to combat cardiac fibrosis is highlighted.

13.
Epilepsy Behav Case Rep ; 8: 108-110, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29204346

RESUMO

Valproic acid (VPA) is a broad-spectrum antiseizure drug used for a variety of clinical conditions, such as epilepsy and mood disorders. Drug-induced hypersensitivity syndrome (DRESS) accompanied by hyponatremia, thrombocytopenia, hypoalbuminemia and elevated aminotransferase has never been reported as an adverse effect of VPA monotherapy during titration for epilepsy in Asian population. Hereby, we present the case of a 73-year-old Chinese male who suffered from DRESS and other complications two weeks after initiating VPA treatment for epilepsy. Understanding the risk associated with VPA-induced DRESS, and taking effective measures to avoid the severe side effects are necessary.

14.
Bone Rep ; 7: 33-40, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28856178

RESUMO

Histone acetylation is an important epigenetic mechanism that controls expression of certain genes. It includes non-sequence-based changes of chromosomal regional structure that can alter the expression of genes. Acetylation of histones is controlled by the activity of two groups of enzymes: the histone acetyltransferases (HATs) and histone deacetylases (HDACs). HDACs remove acetyl groups from the histone tail, which alters its charge and thus promotes compaction of DNA in the nucleosome. HDACs render the chromatin structure into a more compact form of heterochromatin, which makes the genes inaccessible for transcription. By altering the transcriptional activity of bone-associated genes, HDACs control both osteogenesis and osteoclastogenesis. This review presents an overview of the function of HDACs in the modulation of bone formation. Special attention is paid to the use of HDAC inhibitors in mineralized tissue regeneration from cells of dental origin.

15.
Genes Dis ; 3(3): 198-210, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30258889

RESUMO

Temozolomide (TMZ) is an oral alkylating agent used to treat glioblastoma multiforme (GBM) and astrocytomas. However, at least 50% of TMZ treated patients do not respond to TMZ. This is due primarily to the over-expression of O6-methylguanine methyltransferase (MGMT) and/or lack of a DNA repair pathway in GBM cells. Multiple GBM cell lines are known to contain TMZ resistant cells and several acquired TMZ resistant GBM cell lines have been developed for use in experiments designed to define the mechanism of TMZ resistance and the testing of potential therapeutics. However, the characteristics of intrinsic and adaptive TMZ resistant GBM cells have not been systemically compared. This article reviews the characteristics and mechanisms of TMZ resistance in natural and adapted TMZ resistant GBM cell lines. It also summarizes potential treatment options for TMZ resistant GBMs.

16.
EBioMedicine ; 2(11): 1821-6, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26870807

RESUMO

BACKGROUND: CTCs provide prognostic information and their application is under investigation in multiple tumor types. Of the multiple variables inherent in any such process, none is more important to outcome than the appropriateness of the sample source. To address this question, we investigated CTCs in paired peripheral venous and arterial blood specimens obtained from stage IV uveal melanoma patients. METHODS: Blood specimens were obtained from both common femoral arteries and antecubital veins in 17 uveal melanoma patients with multiple hepatic metastases for CTC measurements. FINDING: CTCs were detectable with greater frequency (100%) and in larger numbers (median 5, range 1 to 168) in all arterial blood specimens than in venous samples (52.9%; median 1, range 0 to 8). Patients with hepatic as well as extra-hepatic metastasis showed higher number of arterial CTCs, compared to patients with liver-only metastasis (p = 0.003). There was no significant association between the number of arterial CTCs and the tumor burden within the liver in patients who had liver-only metastases. INTERPRETATION: Our data indicate that arterial blood specimens might be a better source of circulating uveal melanoma cells. Although less conveniently processed, perhaps arterial blood should be evaluated as sample source for measurement of CTCs.


Assuntos
Melanoma/sangue , Melanoma/diagnóstico , Células Neoplásicas Circulantes/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Melanoma/terapia , Pessoa de Meia-Idade , Metástase Neoplásica , Carga Tumoral
17.
Epigenetics ; 10(7): 574-80, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26023847

RESUMO

Amphetamine and methamphetamine addiction is described by specific behavioral alterations, suggesting long-lasting changes in gene and protein expression within specific brain subregions involved in the reward circuitry. Given the persistence of the addiction phenotype at both behavioral and transcriptional levels, several studies have been conducted to elucidate the epigenetic landscape associated with persistent effects of drug use on the mammalian brain. This review discusses recent advances in our comprehension of epigenetic mechanisms underlying amphetamine- or methamphetamine-induced behavioral, transcriptional, and synaptic plasticity. Accumulating evidence demonstrated that drug exposure induces major epigenetic modifications-histone acetylation and methylation, DNA methylation-in a very complex manner. In rare instances, however, the regulation of a specific target gene can be correlated to both epigenetic alterations and behavioral abnormalities. Work is now needed to clarify and validate an epigenetic model of addiction to amphetamines. Investigations that include genome-wide approaches will accelerate the speed of discovery in the field of addiction.


Assuntos
Transtornos Relacionados ao Uso de Anfetaminas/genética , Anfetamina/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Modelos Animais de Doenças , Epigênese Genética/efeitos dos fármacos , Metanfetamina/farmacologia , Acetilação/efeitos dos fármacos , Transtornos Relacionados ao Uso de Anfetaminas/fisiopatologia , Animais , Comportamento Animal , Encéfalo/citologia , Encéfalo/metabolismo , Expressão Gênica , Histona Desacetilases/metabolismo , Histonas/metabolismo , Humanos , Metilação/efeitos dos fármacos , Camundongos , Plasticidade Neuronal , Proto-Oncogene Mas , Ratos
18.
Epigenetics ; 9(10): 1374-81, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25437053

RESUMO

Histone deacetylases (HDAC) play a crucial role in transcriptional regulation and are often deregulated in many cancers. However, global HDAC enzymatic activity has never been investigated in Chronic Lymphocytic Leukemia (CLL). We measured HDAC activity in protein extracts from CD19+ B-cells purified from 114 CLL patients with a median follow-up of 91 months (range: 11-376). HDAC activity was equivalent in CLL and normal B-cells but higher in patients who died during the study than in living patients (152.1 vs. 65.04 pmol; P = 0.0060). Furthermore, HDAC activity correlated with treatment-free survival (TFS; P = 0.0156) and overall survival (OS; P < 0.0001): patients with low HDAC activity (n = 75) had a median TFS and OS of 101 and > 376 months, respectively, whereas patients with high HDAC activity (n = 39) had a median TFS and OS of 47 and 137 months, respectively. Multivariate analyses indicated that HDAC activity is an independent predictor of OS (hazard ratio = 7.68; P = 0.0017). Finally, HDAC activity increased after B-cell receptor stimulation using IgM, suggesting a role for microenvironment stimuli (n = 10; P = 0.0371). In conclusion, high HDAC activity in CLL B-cells is associated with shorter TFS and OS and is an independent marker of OS, refining the use of other prognostic factors. This work provides a biological base for the use of HDAC inhibitors in CLL treatment.


Assuntos
Biomarcadores Tumorais/metabolismo , Histona Desacetilases/metabolismo , Leucemia Linfocítica Crônica de Células B/enzimologia , Leucemia Linfocítica Crônica de Células B/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos B/enzimologia , Estudos de Casos e Controles , Histonas/metabolismo , Humanos , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Células Tumorais Cultivadas
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