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1.
Cell ; 184(24): 5916-5931.e17, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34767757

RESUMO

There is increasing interest in the potential contribution of the gut microbiome to autism spectrum disorder (ASD). However, previous studies have been underpowered and have not been designed to address potential confounding factors in a comprehensive way. We performed a large autism stool metagenomics study (n = 247) based on participants from the Australian Autism Biobank and the Queensland Twin Adolescent Brain project. We found negligible direct associations between ASD diagnosis and the gut microbiome. Instead, our data support a model whereby ASD-related restricted interests are associated with less-diverse diet, and in turn reduced microbial taxonomic diversity and looser stool consistency. In contrast to ASD diagnosis, our dataset was well powered to detect microbiome associations with traits such as age, dietary intake, and stool consistency. Overall, microbiome differences in ASD may reflect dietary preferences that relate to diagnostic features, and we caution against claims that the microbiome has a driving role in ASD.


Assuntos
Transtorno Autístico/microbiologia , Comportamento Alimentar , Microbioma Gastrointestinal , Adolescente , Fatores Etários , Transtorno Autístico/diagnóstico , Comportamento , Criança , Pré-Escolar , Fezes/microbiologia , Feminino , Humanos , Masculino , Fenótipo , Filogenia , Especificidade da Espécie
3.
BMC Psychiatry ; 24(1): 175, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38433233

RESUMO

BACKGROUND: Cannabis use disorder (CUD) is increasingly common and contributes to a range of health and social problems. Cannabidiol (CBD) is a non-intoxicating cannabinoid recognised for its anticonvulsant, anxiolytic and antipsychotic effects with no habit-forming qualities. Results from a Phase IIa randomised clinical trial suggest that treatment with CBD for four weeks reduced non-prescribed cannabis use in people with CUD. This study examines the efficacy, safety and quality of life of longer-term CBD treatment for patients with moderate-to-severe CUD. METHODS/DESIGN: A phase III multi-site, randomised, double-blinded, placebo controlled parallel design of a 12-week course of CBD to placebo, with follow-up at 24 weeks after enrolment. Two hundred and fifty adults with moderate-to-severe CUD (target 20% Aboriginal), with no significant medical, psychiatric or other substance use disorders from seven drug and alcohol clinics across NSW and VIC, Australia will be enrolled. Participants will be administered a daily dose of either 4 mL (100 mg/mL) of CBD or a placebo dispensed every 3-weeks. All participants will receive four-sessions of Cognitive Behavioural Therapy (CBT) based counselling. Primary endpoints are self-reported cannabis use days and analysis of cannabis metabolites in urine. Secondary endpoints include severity of CUD, withdrawal severity, cravings, quantity of use, motivation to stop and abstinence, medication safety, quality of life, physical/mental health, cognitive functioning, and patient treatment satisfaction. Qualitative research interviews will be conducted with Aboriginal participants to explore their perspectives on treatment. DISCUSSION: Current psychosocial and behavioural treatments for CUD indicate that over 80% of patients relapse within 1-6 months of treatment. Pharmacological treatments are highly effective with other substance use disorders but there are no approved pharmacological treatments for CUD. CBD is a promising candidate for CUD treatment due to its potential efficacy for this indication and excellent safety profile. The anxiolytic, antipsychotic and neuroprotective effects of CBD may have added benefits by reducing many of the mental health and cognitive impairments reported in people with regular cannabis use. TRIAL REGISTRATION: Australian and New Zealand Clinical Trial Registry: ACTRN12623000526673 (Registered 19 May 2023).


Assuntos
Ansiolíticos , Antipsicóticos , Canabidiol , Cannabis , Alucinógenos , Abuso de Maconha , Transtornos Relacionados ao Uso de Substâncias , Adulto , Humanos , Canabidiol/uso terapêutico , Qualidade de Vida , Austrália , Ensaios Clínicos Controlados Aleatórios como Assunto , Ensaios Clínicos Fase III como Assunto
4.
J Org Chem ; 88(21): 15007-15017, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37862461

RESUMO

In the ever-expanding realm of organic fluorophores, structurally simple and synthetically straightforward molecules with unique photophysical properties have received special attention. Among these, 1,4-dihydropyridine (DHP) is an important scaffold that permits fine-tuning of their photophysical properties through substituents on the periphery. Herein, we describe a series of solid-emissive N-substituted 2,6-dimethyl-4-methylene-1,4-dihydropyridine derivatives appended with electron-withdrawing substituents (dicyanomethylene or 2-dicyanomethylene-3-cyano-2,5-dihydrofuran) at the C-4 position and alkyl or alkylaryl groups on the DHP nitrogen. Electronic and steric tuning exerted by these substituents resulted in interesting photophysical properties such as negative solvatochromism, solidstate, and aggregation-induced emission (AIE). Theoretical calculations were carried out to explain the solvatochromic properties. Insight into the AIE properties was obtained through variable-temperature nuclear magnetic resonance and viscosity- and temperature-dependent emission studies. The variations in molecular packing in the crystal lattice with changes in the N-substituents contributed to the tuning of solid state emission properties. Detection of aromatic volatile organic compounds (VOCs) was achieved using the aggregates of the DHP derivatives. Among the VOCs, p-xylene elicited a significant enhancement in emission, allowing its detection at submicromolar levels.

5.
Langenbecks Arch Surg ; 408(1): 203, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37212868

RESUMO

AIM: This study reports venous thromboembolism (VTE) rates following colectomy for diverticular disease to explore the magnitude of postoperative VTE risk in this population and identify high risk subgroups of interest. METHOD: English national cohort study of colectomy patients between 2000 and 2019 using linked primary (Clinical Practice Research Datalink) and secondary (Hospital Episode Statistics) care data. Stratified by admission type, absolute incidence rates (IR) per 1000 person-years and adjusted incidence rate ratios (aIRR) were calculated for 30- and 90-day post-colectomy VTE. RESULTS: Of 24,394 patients who underwent colectomy for diverticular disease, over half (57.39%) were emergency procedures with the highest VTE rate seen in patients ≥70-years-old (IR 142.27 per 1000 person-years, 95%CI 118.32-171.08) at 30 days post colectomy. Emergency resections (IR 135.18 per 1000 person-years, 95%CI 115.72-157.91) had double the risk (aIRR 2.07, 95%CI 1.47-2.90) of developing a VTE at 30 days following colectomy compared to elective resections (IR 51.14 per 1000 person-years, 95%CI 38.30-68.27). Minimally invasive surgery (MIS) was shown to be associated with a 64% reduction in VTE risk (aIRR 0.36 95%CI 0.20-0.65) compared to open colectomies at 30 days post-op. At 90 days following emergency resections, VTE risks remained raised compared to elective colectomies. CONCLUSION: Following emergency colectomy for diverticular disease, the VTE risk is approximately double compared to elective resections at 30 days while MIS was found to be associated with a reduced risk of VTE. This suggests advancements in postoperative VTE prevention in diverticular disease patients should focus on those undergoing emergency colectomies.


Assuntos
Doenças Diverticulares , Tromboembolia Venosa , Humanos , Idoso , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle , Estudos de Coortes , Fatores de Risco , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Colectomia/efeitos adversos , Colectomia/métodos , Doenças Diverticulares/epidemiologia , Doenças Diverticulares/cirurgia , Doenças Diverticulares/complicações
6.
Rep Pract Oncol Radiother ; 28(4): 454-462, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37795230

RESUMO

Background: The aim was perusal of the treatment strategies, clinical outcomes and factors impacting these outcomes in thymoma. Materials and methods: A total of 119 patients diagnosed and treated cases of thymoma, at our hospital, were taken for analysis. Thirty-one patients were excluded due to inadequate medical records. Descriptive statistics were used to report demographic and clinical characteristics. Time period between diagnosis and death was defined as overall survival (OS). Multivariate analysis (MVA), using cox regression modelling, was done by including clinicopathological factors in a bid to identify prognostic factors influencing OS. SPSS version 26 was used for statistical analysis. Results: The mean age of the patients was 52.17 years and 39 (44.3%), 19 (21.6%), 17 (1.3%) and 13 (4.8%) patients presented with Masaoka stage II, IV, III and I, respectively. Surgery was done in 64 (72.7%) of the patients as a part of the treatment strategy. Radiotherapy was administered to a total of 57 patients with a median dose of 50.4 Gy. Early Masaoka stage at presentation and use of surgery in the treatment plan were statistically significant prognostic factors for a better overall survival on multivariate analysis. Conclusion: Judicious use of radiotherapy and chemotherapy in locally advanced cases may render them resectable. In a bid to gain good survival rates, aggressive multimodality treatment should be offered to the patients.

7.
Chem Res Toxicol ; 35(11): 1983-1996, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36201358

RESUMO

The development of rapidly acting cyanide countermeasures using intramuscular injection (IM) represents an unmet medical need to mitigate toxicant exposures in mass casualty settings. Previous work established that cisplatin and other platinum(II) or platinum(IV)-based agents effectively mitigate cyanide toxicity in zebrafish. Cyanide's in vivo reaction with platinum-containing materials was proposed to reduce the risk of acute toxicities. However, cyanide antidote activity depended on a formulation of platinum-chloride salts with dimethyl sulfoxide (DMSO) followed by dilution in phosphate-buffered saline (PBS). A working hypothesis to explain the DMSO requirement is that the formation of platinum-sulfoxide complexes activates the cyanide scavenging properties of platinum. Preparations of isolated NaPtCl5-DMSO and Na (NH3)2PtCl-DMSO complexes in the absence of excess DMSO provided agents with enhanced reactivity toward cyanide in vitro and fully recapitulated in vivo cyanide rescue in zebrafish and mouse models. The enhancement of the cyanide scavenging effects of the DMSO ligand could be attributed to the activation of platinum(IV) and (II) with a sulfur ligand. Unfortunately, the efficacy of DMSO complexes was not robust when administered IM. Alternative Pt(II) materials containing sulfide and amine ligands in bidentate complexes show enhanced reactivity toward cyanide addition. The cyanide addition products yielded tetracyanoplatinate(II), translating to a stoichiometry of 1:4 Pt to each cyanide scavenger. These new agents demonstrate a robust and enhanced potency over the DMSO-containing complexes using IM administration in mouse and rabbit models of cyanide toxicity. Using the zebrafish model with these Pt(II) complexes, no acute cardiotoxicity was detected, and dose levels required to reach lethality exceeded 100 times the effective dose. Data are presented to support a general chemical design approach that can expand a new lead candidate series for developing next-generation cyanide countermeasures.


Assuntos
Antineoplásicos , Platina , Camundongos , Coelhos , Animais , Platina/química , Peixe-Zebra , Cianetos , Dimetil Sulfóxido , Ligantes , Sulfetos , Antineoplásicos/farmacologia
8.
Crit Rev Food Sci Nutr ; : 1-15, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36268992

RESUMO

In this milieu, ozone technology has emerged as an avant-garde non-thermal mode of disinfection with potential applications in the food industry. This eco-friendly technology has a comprehendible adeptness in replacing alternative chemical sanitizers and is recognized as a generally safe disinfectant for fruits and vegetables. Several researchers have been focusing on the biochemical impacts of ozone on different quantitative and qualitative aspects of fruits and vegetables. A collection of those works is presented in this review highlighting the effect of ozone on the functional, antioxidant, and rheological properties of food. This can be a benevolent tool for discovering the processing states of ozone applications and ensuing influence on safety and quality attributes of previously studied foods and opening further research areas. It extends shelf life and never leaves any harmful residues on the product since it decomposes to form oxygen. It was seen that the impact on a specific property of food was dependent on the ozone concentration and treatment time, and the adverse effects of ozone exposure can be alleviated once the processing conditions are optimized. The present review can be used as a baseline for designing different food processing operations involving ozone.

11.
Drug Dev Ind Pharm ; 48(9): 480-490, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36165580

RESUMO

BACKGROUND: Cervical cancer continues to be the leading cause of death worldwide despite the availability of many therapeutic options. Biogenic synthesis of metal nanoparticles paves a new way for the development of targeted drug delivery modalities of cancer therapeutics. OBJECTIVE: In this study, we demonstrate the efficacy of biosynthesized silver nanoparticles from methanolic leaf extract of Citrus hystrix as an anticancer agent used against cervical cancer cell line HeLa. METHODS: The addition of 1 mM silver nitrate to methanolic leaf extract of Citrus hystrix resulted in the biosynthesis of silver nanoparticles during the reaction mixture and was incubated in the dark for 1 h at pH 9 with gentle stirring. Characterization of synthesized NPs was carried out using various analyses. MTT assay, DAPI, AO/EB double staining, and reverse transcriptase-PCR (RT-PCR) analysis were carried out to evaluate the cytotoxic activity of Citrus hystrix mediated green synthesized silver nanoparticles (ChAgNPs). RESULTS AND CONCLUSION: The absorption band at 430 nm, as shown by UV-vis spectroscopy revealed the formation of AgNPs. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis shows that most of the ChAgNPs were spherical in shape and X-ray diffraction (XRD) patterns revealed the crystalline nature of the particles. Moreover, its potent cytotoxic effect on the HeLa cell line was analyzed using MTT assay with an IC50 value of 56 µg/ml by decreasing the cell viability in a dose and time-dependent manner. The induced apoptotic activity was confirmed by DAPI and double staining methods. Autophagic and apoptotic mediated cell death in ChAgNPs treated HeLa cell line was confirmed by staining procedures and RT-PCR methods.


Assuntos
Antineoplásicos , Citrus , Nanopartículas Metálicas , Neoplasias do Colo do Útero , Humanos , Feminino , Células HeLa , Nanopartículas Metálicas/química , Neoplasias do Colo do Útero/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Prata , Antineoplásicos/química , Antibacterianos/química
12.
FASEB J ; 34(1): 1546-1557, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31914600

RESUMO

G protein-coupled receptors (GPCRs) comprise the largest group of membrane receptors in eukaryotic genomes and collectively they regulate nearly all cellular processes. Despite the widely recognized importance of this class of proteins, many GPCRs remain understudied. G protein-coupled receptor 27 (Gpr27) is an orphan GPCR that displays high conservation during vertebrate evolution. Although, GPR27 is known to be expressed in tissues that regulate metabolism including the pancreas, skeletal muscle, and adipose tissue, its functions are poorly characterized. Therefore, to investigate the potential roles of Gpr27 in energy metabolism, we generated a whole body gpr27 knockout zebrafish line. Loss of gpr27 potentiated the elevation in glucose levels induced by pharmacological or nutritional perturbations. We next leveraged a mass spectrometry metabolite profiling platform to identify other potential metabolic functions of Gpr27. Notably, genetic deletion of gpr27 elevated medium-chain acylcarnitines, in particular C6-hexanoylcarnitine, C8-octanoylcarnitine, C9-nonanoylcarnitine, and C10-decanoylcarnitine, lipid species known to be associated with insulin resistance in humans. Concordantly, gpr27 deletion in zebrafish abrogated insulin-dependent Akt phosphorylation and glucose utilization. Finally, loss of gpr27 increased the expression of key enzymes in carnitine shuttle complex, in particular the homolog to the brain-specific isoform of CPT1C which functions as a hypothalamic energy senor. In summary, our findings shed light on the biochemical functions of Gpr27 by illuminating its role in lipid metabolism, insulin signaling, and glucose homeostasis.


Assuntos
Carnitina/análogos & derivados , Glucose/metabolismo , Homeostase/genética , Resistência à Insulina/genética , Receptores Acoplados a Proteínas G/genética , Peixe-Zebra/genética , Animais , Carnitina/genética , Carnitina/metabolismo , Carnitina O-Palmitoiltransferase/metabolismo , Deleção de Genes , Glucose/genética , Insulina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/genética , Peixe-Zebra/metabolismo
13.
J Phys Chem A ; 124(43): 8959-8977, 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-32946236

RESUMO

A new approach for quantitively assessing putative crystal structures with applications in crystal structure prediction (CSP) is introduced that is based upon experimental solution- and magic-angle spinning (MAS) solid-state NMR data and density functional theory (DFT) calculation. For the specific case of tolfenamic acid (TFA), we consider experimental solution-state NMR for a range of solvents, experimental MAS NMR of polymorphs I and II, and DFT calculations for four polymorphs. The change in NMR chemical shift observed in passing from the solution state to the solid state (ΔδExperimental) is calculated as the difference between 1H and 13C experimental solid-state chemical shifts for each polymorphic form (δSolid expt) and the corresponding solution-state NMR chemical shifts (δSolution expt). Separately, we use the gauge-included projector augmented wave (GIPAW) method to calculate the NMR chemical shifts for each form (δSolid calc) and for TFA in solution (δSolution calc) using the dynamic 3D solution conformational ensemble determined from NMR spectroscopy. The calculated change in passing from the solution state to the solid state (ΔδCalculated) is then calculated as the difference of δSolid calc and δSolution calc. Regression analysis for ΔδCalculated against ΔδExperimental followed by a t-test for statistical significance provides a robust quantitative assessment. We show that this assessment clearly identifies the correct polymorph, i.e., when comparing ΔδExperimental based on the experimental MAS NMR chemical shifts of form I or II with ΔδCalculated based on calculated chemical shifts for polymorphs I, II, III, and IV. Complementarity to the established approach of comparing δSolid expt to δSolid calc is explored. We further show that our approach is applicable if there are no solid-state crystal structure data. Specifically, δSolid calc in ΔδCalculated is replaced by the chemical shift for an isolated molecule with a specific conformation. Sampling conformations at specific 15° angle values and comparing them against experimental 13C chemical shift data for forms I and II identifies matching narrow ranges of conformations, successfully predicting the conformation of tolfenamic acid in each form. This methodology can therefore be used in crystal structure prediction to both reduce the initial conformational search space and also quantitatively assess subsequent putative structures to reliably and unambiguously identify the correct structure.

14.
Nature ; 508(7495): 249-53, 2014 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-24572353

RESUMO

Epistasis is the phenomenon whereby one polymorphism's effect on a trait depends on other polymorphisms present in the genome. The extent to which epistasis influences complex traits and contributes to their variation is a fundamental question in evolution and human genetics. Although often demonstrated in artificial gene manipulation studies in model organisms, and some examples have been reported in other species, few examples exist for epistasis among natural polymorphisms in human traits. Its absence from empirical findings may simply be due to low incidence in the genetic control of complex traits, but an alternative view is that it has previously been too technically challenging to detect owing to statistical and computational issues. Here we show, using advanced computation and a gene expression study design, that many instances of epistasis are found between common single nucleotide polymorphisms (SNPs). In a cohort of 846 individuals with 7,339 gene expression levels measured in peripheral blood, we found 501 significant pairwise interactions between common SNPs influencing the expression of 238 genes (P < 2.91 × 10(-16)). Replication of these interactions in two independent data sets showed both concordance of direction of epistatic effects (P = 5.56 × 10(-31)) and enrichment of interaction P values, with 30 being significant at a conservative threshold of P < 9.98 × 10(-5). Forty-four of the genetic interactions are located within 5 megabases of regions of known physical chromosome interactions (P = 1.8 × 10(-10)). Epistatic networks of three SNPs or more influence the expression levels of 129 genes, whereby one cis-acting SNP is modulated by several trans-acting SNPs. For example, MBNL1 is influenced by an additive effect at rs13069559, which itself is masked by trans-SNPs on 14 different chromosomes, with nearly identical genotype-phenotype maps for each cis-trans interaction. This study presents the first evidence, to our knowledge, for many instances of segregating common polymorphisms interacting to influence human traits.


Assuntos
Epistasia Genética/genética , Regulação da Expressão Gênica/genética , Transcrição Gênica/genética , Estudos de Coortes , Europa (Continente)/etnologia , Feminino , Perfilação da Expressão Gênica , Estudos de Associação Genética , Humanos , Desequilíbrio de Ligação , Masculino , Linhagem , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas , Reprodutibilidade dos Testes
15.
Twin Res Hum Genet ; 23(2): 109-111, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32383421

RESUMO

Nick Martin is a pioneer in recognizing the need for large sample size to study the complex, heterogeneous and polygenic disorders of common mental disorders. In the predigital era, questionnaires were mailed to thousands of twin pairs around Australia. Always quick to adopt new technology, Nick's studies progressed to phone interviews and then online. Moreover, Nick was early to recognize the value of collecting DNA samples. As genotyping technologies improved over the years, these twin and family cohorts were used for linkage, candidate gene and genome-wide association studies. These cohorts have underpinned many analyses to disentangle the complex web of genetic and lifestyle factors associated with mental health. With characteristic foresight, Nick is chief investigator of our Australian Genetics of Depression Study, which has recruited 16,000 people with self-reported depression (plus DNA samples) over a time frame of a few months - analyses are currently ongoing. The mantra of sample size, sample size, sample size has guided Nick's research over the last 30 years and continues to do so.


Assuntos
Depressão/genética , Transtornos Mentais/genética , Herança Multifatorial/genética , Austrália/epidemiologia , Depressão/história , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , História do Século XX , História do Século XXI , Humanos , Transtornos Mentais/história , Gêmeos/genética , Gêmeos/história
16.
Aust N Z J Psychiatry ; 54(1): 46-56, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30995080

RESUMO

OBJECTIVE: The current international trend is to create large datasets with existing data and/or deposit newly collected data into repositories accessible to the scientific community. These practices lead to more efficient data sharing, better detection of small effects, modelling of confounders, establishment of sample generalizability and identification of differences between any given disorders. In Australia, to facilitate such data-sharing and collaborative opportunities, the Neurobiology in Youth Mental Health Partnership was created. This initiative brings together specialised researchers from around Australia to work towards a better understanding of the cross-diagnostic neurobiology of youth mental health and the translation of this knowledge into clinical practice. One of the mandates of the partnership was to develop a protocol for harmonised prospective collection of data across research centres in the field of youth mental health in order to create large datasets. METHODS: Four key research modalities were identified: clinical assessments, brain imaging, neurocognitive assessment and collection of blood samples. This paper presents the consensus set of assessments/data collection that has been selected by experts in each domain. CONCLUSION: The use of this core set of data will facilitate the pooling of psychopathological and neurobiological data into large datasets allowing researchers to tackle important questions requiring very large numbers. The aspiration of this transdiagnostic approach is a better understanding of the mechanisms underlying mental illnesses.


Assuntos
Big Data , Coleta de Dados , Disseminação de Informação , Transtornos Mentais/diagnóstico , Adolescente , Adulto , Criança , Humanos , Colaboração Intersetorial , Adulto Jovem
17.
J Neurosci ; 38(31): 6921-6932, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29959237

RESUMO

Muscarinic receptor antagonists act as potent inducers of oligodendrocyte differentiation and accelerate remyelination. However, the use of muscarinic antagonists in the clinic is limited by poor understanding of the operant receptor subtype, and questions regarding possible species differences between rodents and humans. Based on high selective expression in human oligodendrocyte progenitor cells (OPCs), we hypothesized that M3R is the functionally relevant receptor. Lentiviral M3R knockdown in human primary CD140a/PDGFαR+ OPCs resulted in enhanced differentiation in vitro and substantially reduced the calcium response following muscarinic agonist treatment. Importantly, following transplantation in hypomyelinating shiverer/rag2 mice, M3R knockdown improved remyelination by human OPCs. Furthermore, conditional M3R ablation in adult NG2-expressing OPCs increased oligodendrocyte differentiation and led to improved spontaneous remyelination in mice. Together, we demonstrate that M3R receptor mediates muscarinic signaling in human OPCs that act to delay differentiation and remyelination, suggesting that M3 receptors are viable targets for human demyelinating disease.SIGNIFICANCE STATEMENT The identification of drug targets aimed at improving remyelination in patients with demyelination disease is a key step in development of effective regenerative therapies to treat diseases, such as multiple sclerosis. Muscarinic receptor antagonists have been identified as effective potentiators of remyelination, but the receptor subtypes that mediate these receptors are unclear. In this study, we show that genetic M3R ablation in both mouse and human cells results in improved remyelination and is mediated by acceleration of oligodendrocyte commitment from oligodendrocyte progenitor cells. Therefore, M3R represents an attractive target for induced remyelination in human disease.


Assuntos
Bainha de Mielina/fisiologia , Neurogênese/fisiologia , Células Precursoras de Oligodendrócitos/fisiologia , Receptor Muscarínico M3/fisiologia , Remielinização/fisiologia , Animais , Transplante de Tecido Encefálico , Sinalização do Cálcio , Células Cultivadas , Transplante de Tecido Fetal , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Camundongos Mutantes Neurológicos , Agonistas Muscarínicos/farmacologia , Antagonistas Muscarínicos/farmacologia , Prosencéfalo/embriologia , Prosencéfalo/transplante , Interferência de RNA , Receptor Muscarínico M3/agonistas , Receptor Muscarínico M3/antagonistas & inibidores , Medula Espinal/química , Medula Espinal/ultraestrutura
18.
Hum Mol Genet ; 25(24): 5332-5338, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27798101

RESUMO

The mitochondrial and nuclear genomes coordinate and co-evolve in eukaryotes in order to adapt to environmental changes. Variation in the mitochondrial genome is capable of affecting expression of genes on the nuclear genome. Sex-specific mitochondrial genetic control of gene expression has been demonstrated in Drosophila melanogaster, where males were found to drive most of the total variation in gene expression. This has potential implications for male-related health and disease resulting from variation in mtDNA solely inherited from the mother. We used a family-based study comprised of 47,323 gene expression probes and 78 mitochondrial SNPs (mtSNPs) from n = 846 individuals to examine the extent of mitochondrial genetic control of gene expression in humans. This identified 15 significant probe-mtSNP associations (P<10-8) corresponding to 5 unique genes on the mitochondrial and nuclear genomes, with three of these genes corresponding to mitochondrial genetic control of gene expression in the nuclear genome. The associated mtSNPs for three genes (one cis and two trans associations) were replicated (P < 0.05) in an independent dataset of n = 452 unrelated individuals. There was no evidence for sexual dimorphic gene expression in any of these five probes. Sex-specific effects were examined by applying our analysis to males and females separately and testing for differences in effect size. The MEST gene was identified as having the most significantly different effect sizes across the sexes (P≈10-7). MEST was similarly expressed in males and females with the G allele; however, males with the C allele are highly expressed for MEST, while females show no expression of the gene. This study provides evidence for the mitochondrial genetic control of expression of several genes in humans, with little evidence found for sex-specific effects.


Assuntos
DNA Mitocondrial/genética , Regulação da Expressão Gênica/genética , Mitocôndrias/genética , Biossíntese de Proteínas/genética , Alelos , Animais , Núcleo Celular/genética , Cromossomos/genética , Drosophila melanogaster/genética , Feminino , Humanos , Masculino , Polimorfismo de Nucleotídeo Único/genética , Caracteres Sexuais
19.
Am J Hum Genet ; 97(1): 75-85, 2015 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-26119815

RESUMO

We tested whether DNA-methylation profiles account for inter-individual variation in body mass index (BMI) and height and whether they predict these phenotypes over and above genetic factors. Genetic predictors were derived from published summary results from the largest genome-wide association studies on BMI (n ∼ 350,000) and height (n ∼ 250,000) to date. We derived methylation predictors by estimating probe-trait effects in discovery samples and tested them in external samples. Methylation profiles associated with BMI in older individuals from the Lothian Birth Cohorts (LBCs, n = 1,366) explained 4.9% of the variation in BMI in Dutch adults from the LifeLines DEEP study (n = 750) but did not account for any BMI variation in adolescents from the Brisbane Systems Genetic Study (BSGS, n = 403). Methylation profiles based on the Dutch sample explained 4.9% and 3.6% of the variation in BMI in the LBCs and BSGS, respectively. Methylation profiles predicted BMI independently of genetic profiles in an additive manner: 7%, 8%, and 14% of variance of BMI in the LBCs were explained by the methylation predictor, the genetic predictor, and a model containing both, respectively. The corresponding percentages for LifeLines DEEP were 5%, 9%, and 13%, respectively, suggesting that the methylation profiles represent environmental effects. The differential effects of the BMI methylation profiles by age support previous observations of age modulation of genetic contributions. In contrast, methylation profiles accounted for almost no variation in height, consistent with a mainly genetic contribution to inter-individual variation. The BMI results suggest that combining genetic and epigenetic information might have greater utility for complex-trait prediction.


Assuntos
Estatura/genética , Metilação de DNA/genética , Obesidade/genética , Fenótipo , Adolescente , Adulto , Análise de Variância , Índice de Massa Corporal , Estudos de Coortes , Estudo de Associação Genômica Ampla/métodos , Genótipo , Humanos , Pessoa de Meia-Idade , Modelos Genéticos , Países Baixos , Escócia
20.
J Neurol Neurosurg Psychiatry ; 89(10): 1016-1023, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29706605

RESUMO

OBJECTIVE: To determine the prevalence of hypermetabolism, relative to body composition, in amyotrophic lateral sclerosis (ALS) and its relationship with clinical features of disease and survival. METHODS: Fifty-eight patients with clinically definite or probable ALS as defined by El Escorial criteria, and 58 age and sex-matched control participants underwent assessment of energy expenditure. Our primary outcome was the prevalence of hypermetabolism in cases and controls. Longitudinal changes in clinical parameters between hypermetabolic and normometabolic patients with ALS were determined for up to 12 months following metabolic assessment. Survival was monitored over a 30-month period following metabolic assessment. RESULTS: Hypermetabolism was more prevalent in patients with ALS than controls (41% vs 12%, adjusted OR=5.4; p<0.01). Change in body weight, body mass index and fat mass (%) was similar between normometabolic and hypermetabolic patients with ALS. Mean lower motor neuron score (SD) was greater in hypermetabolic patients when compared with normometabolic patients (4 (0.3) vs 3 (0.7); p=0.04). In the 12 months following metabolic assessment, there was a greater change in Revised ALS Functional Rating Scale score in hypermetabolic patients when compared with normometabolic patients (-0.68 points/month vs -0.39 points/month; p=0.01). Hypermetabolism was inversely associated with survival. Overall, hypermetabolism increased the risk of death during follow-up to 220% (HR 3.2, 95% CI 1.1 to 9.4, p=0.03). CONCLUSIONS AND RELEVANCE: Hypermetabolic patients with ALS have a greater level of lower motor neuron involvement, faster rate of functional decline and shorter survival. The metabolic index could be important for informing prognosis in ALS.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Composição Corporal/fisiologia , Índice de Massa Corporal , Metabolismo Energético/fisiologia , Idoso , Esclerose Lateral Amiotrófica/mortalidade , Estudos de Casos e Controles , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida
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