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1.
Cell ; 177(4): 1010-1021.e32, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-30981557

RESUMO

Genome sequences are known for two archaic hominins-Neanderthals and Denisovans-which interbred with anatomically modern humans as they dispersed out of Africa. We identified high-confidence archaic haplotypes in 161 new genomes spanning 14 island groups in Island Southeast Asia and New Guinea and found large stretches of DNA that are inconsistent with a single introgressing Denisovan origin. Instead, modern Papuans carry hundreds of gene variants from two deeply divergent Denisovan lineages that separated over 350 thousand years ago. Spatial and temporal structure among these lineages suggest that introgression from one of these Denisovan groups predominantly took place east of the Wallace line and continued until near the end of the Pleistocene. A third Denisovan lineage occurs in modern East Asians. This regional mosaic suggests considerable complexity in archaic contact, with modern humans interbreeding with multiple Denisovan groups that were geographically isolated from each other over deep evolutionary time.


Assuntos
Introgressão Genética/genética , Haplótipos/genética , Hominidae/genética , Animais , Povo Asiático/genética , Evolução Biológica , Fluxo Gênico , Variação Genética/genética , Genoma Humano/genética , Humanos , Indonésia , Homem de Neandertal/genética , Oceania
2.
PLoS Genet ; 18(12): e1010470, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36480515

RESUMO

Modern humans have admixed with multiple archaic hominins. Papuans, in particular, owe up to 5% of their genome to Denisovans, a sister group to Neanderthals whose remains have only been identified in Siberia and Tibet. Unfortunately, the biological and evolutionary significance of these introgression events remain poorly understood. Here we investigate the function of both Denisovan and Neanderthal alleles characterised within a set of 56 genomes from Papuan individuals. By comparing the distribution of archaic and non-archaic variants we assess the consequences of archaic admixture across a multitude of different cell types and functional elements. We observe an enrichment of archaic alleles within cis-regulatory elements and transcribed regions of the genome, with Denisovan variants strongly affecting elements active within immune-related cells. We identify 16,048 and 10,032 high-confidence Denisovan and Neanderthal variants that fall within annotated cis-regulatory elements and with the potential to alter the affinity of multiple transcription factors to their cognate DNA motifs, highlighting a likely mechanism by which introgressed DNA can impact phenotypes. Lastly, we experimentally validate these predictions by testing the regulatory potential of five Denisovan variants segregating within Papuan individuals, and find that two are associated with a significant reduction of transcriptional activity in plasmid reporter assays. Together, these data provide support for a widespread contribution of archaic DNA in shaping the present levels of modern human genetic diversity, with different archaic ancestries potentially affecting multiple phenotypic traits within non-Africans.


Assuntos
Evolução Molecular , Hominidae , Sistema Imunitário , Homem de Neandertal , Humanos , Hominidae/genética , Homem de Neandertal/genética , Papua Nova Guiné
3.
Diabetologia ; 67(7): 1413-1428, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38662134

RESUMO

AIMS/HYPOTHESIS: Our aim was to characterise the in-depth metabolic response to aerobic exercise and the impact of residual pancreatic beta cell function in type 1 diabetes. We also aimed to use the metabolome to distinguish individuals with type 1 diabetes with reduced maximal aerobic capacity in exercise defined by V ˙ O 2peak . METHODS: Thirty participants with type 1 diabetes (≥3 years duration) and 30 control participants were recruited. Groups did not differ in age or sex. After quantification of peak stimulated C-peptide, participants were categorised into those with undetectable (<3 pmol/l), low (3-200 pmol/l) or high (>200 pmol/l) residual beta cell function. Maximal aerobic capacity was assessed by V ˙ O 2peak test and did not differ between control and type 1 diabetes groups. All participants completed 45 min of incline treadmill walking (60% V ˙ O 2peak ) with venous blood taken prior to exercise, immediately post exercise and after 60 min recovery. Serum was analysed using targeted metabolomics. Metabolomic data were analysed by multivariate statistics to define the metabolic phenotype of exercise in type 1 diabetes. Receiver operating characteristic (ROC) curves were used to identify circulating metabolomic markers of maximal aerobic capacity ( V ˙ O 2peak ) during exercise in health and type 1 diabetes. RESULTS: Maximal aerobic capacity ( V ˙ O 2peak ) inversely correlated with HbA1c in the type 1 diabetes group (r2=0.17, p=0.024). Higher resting serum tricarboxylic acid cycle metabolites malic acid (fold change 1.4, p=0.001) and lactate (fold change 1.22, p=1.23×10-5) differentiated people with type 1 diabetes. Higher serum acylcarnitines (AC) (AC C14:1, F value=12.25, p=0.001345; AC C12, F value=11.055, p=0.0018) were unique to the metabolic response to exercise in people with type 1 diabetes. C-peptide status differentially affected metabolic responses in serum ACs during exercise (AC C18:1, leverage 0.066; squared prediction error 3.07). The malic acid/pyruvate ratio in rested serum was diagnostic for maximal aerobic capacity ( V ˙ O 2peak ) in people with type 1 diabetes (ROC curve AUC 0.867 [95% CI 0.716, 0.956]). CONCLUSIONS/INTERPRETATION: The serum metabolome distinguishes high and low maximal aerobic capacity and has diagnostic potential for facilitating personalised medicine approaches to manage aerobic exercise and fitness in type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1 , Exercício Físico , Metaboloma , Humanos , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/fisiopatologia , Masculino , Feminino , Adulto , Metaboloma/fisiologia , Exercício Físico/fisiologia , Consumo de Oxigênio/fisiologia , Teste de Esforço , Metabolômica/métodos , Adulto Jovem , Peptídeo C/sangue , Pessoa de Meia-Idade , Células Secretoras de Insulina/metabolismo
4.
J Biol Chem ; 299(6): 104792, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37150321

RESUMO

Necroptosis is a form of regulated cell death triggered by various host and pathogen-derived molecules during infection and inflammation. The essential step leading to necroptosis is phosphorylation of the mixed lineage kinase domain-like protein by receptor-interacting protein kinase 3. Caspase-8 cleaves receptor-interacting protein kinases to block necroptosis, so synthetic caspase inhibitors are required to study this process in experimental models. However, it is unclear how caspase-8 activity is regulated in a physiological setting. The active site cysteine of caspases is sensitive to oxidative inactivation, so we hypothesized that oxidants generated at sites of inflammation can inhibit caspase-8 and promote necroptosis. Here, we discovered that hypothiocyanous acid (HOSCN), an oxidant generated in vivo by heme peroxidases including myeloperoxidase and lactoperoxidase, is a potent caspase-8 inhibitor. We found HOSCN was able to promote necroptosis in mouse fibroblasts treated with tumor necrosis factor. We also demonstrate purified caspase-8 was inactivated by low concentrations of HOSCN, with the predominant product being a disulfide-linked dimer between Cys360 and Cys409 of the large and small catalytic subunits. We show oxidation still occurred in the presence of reducing agents, and reduction of the dimer was slow, consistent with HOSCN being a powerful physiological caspase inhibitor. While the initial oxidation product is a dimer, further modification also occurred in cells treated with HOSCN, leading to higher molecular weight caspase-8 species. Taken together, these findings indicate major disruption of caspase-8 function and suggest a novel mechanism for the promotion of necroptosis at sites of inflammation.


Assuntos
Caspase 8 , Necroptose , Oxidantes , Fatores de Necrose Tumoral , Animais , Camundongos , Caspase 8/química , Caspase 8/metabolismo , Inflamação/metabolismo , Necroptose/efeitos dos fármacos , Oxidantes/metabolismo , Oxidantes/farmacologia , Oxirredução/efeitos dos fármacos , Fatores de Necrose Tumoral/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Fibroblastos/metabolismo , Peroxidase , Lactoperoxidase , Domínio Catalítico
5.
Exp Physiol ; 109(1): 55-65, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-36966478

RESUMO

Muscle spindles encode mechanosensory information by mechanisms that remain only partially understood. Their complexity is expressed in mounting evidence of various molecular mechanisms that play essential roles in muscle mechanics, mechanotransduction and intrinsic modulation of muscle spindle firing behaviour. Biophysical modelling provides a tractable approach to achieve more comprehensive mechanistic understanding of such complex systems that would be difficult/impossible by more traditional, reductionist means. Our objective here was to construct the first integrative biophysical model of muscle spindle firing. We leveraged current knowledge of muscle spindle neuroanatomy and in vivo electrophysiology to develop and validate a biophysical model that reproduces key in vivo muscle spindle encoding characteristics. Crucially, to our knowledge, this is the first computational model of mammalian muscle spindle that integrates the asymmetric distribution of known voltage-gated ion channels (VGCs) with neuronal architecture to generate realistic firing profiles, both of which seem likely to be of great biophysical importance. Results predict that particular features of neuronal architecture regulate specific characteristics of Ia encoding. Computational simulations also predict that the asymmetric distribution and ratios of VGCs is a complementary and, in some instances, orthogonal means to regulate Ia encoding. These results generate testable hypotheses and highlight the integral role of peripheral neuronal structure and ion channel composition and distribution in somatosensory signalling.


Assuntos
Mecanotransdução Celular , Fusos Musculares , Animais , Fusos Musculares/fisiologia , Neurônios , Canais Iônicos , Fenômenos Eletrofisiológicos , Mamíferos
6.
Exp Physiol ; 109(1): 81-99, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37656490

RESUMO

A metabotropic glutamate receptor coupled to phospholipase D (PLD-mGluR) was discovered in the hippocampus over three decades ago. Its pharmacology and direct linkage to PLD activation are well established and indicate it is a highly atypical glutamate receptor. A receptor with the same pharmacology is present in spindle primary sensory terminals where its blockade can totally abolish, and its activation can double, the normal stretch-evoked firing. We report here the first identification of this PLD-mGluR protein, by capitalizing on its expression in primary mechanosensory terminals, developing an enriched source, pharmacological profiling to identify an optimal ligand, and then functionalizing it as a molecular tool. Evidence from immunofluorescence, western and far-western blotting indicates PLD-mGluR is homomeric GluK2, since GluK2 is the only glutamate receptor protein/receptor subunit present in spindle mechanosensory terminals. Its expression was also found in the lanceolate palisade ending of hair follicle, also known to contain the PLD-mGluR. Finally, in a mouse model with ionotropic function ablated in the GluK2 subunit, spindle glutamatergic responses were still present, confirming it acts purely metabotropically. We conclude the PLD-mGluR is a homomeric GluK2 kainate receptor signalling purely metabotropically and it is common to other, perhaps all, primary mechanosensory endings.


Assuntos
Fosfolipase D , Receptores de Glutamato Metabotrópico , Animais , Camundongos , Hipocampo/metabolismo , Terminações Nervosas/metabolismo , Fosfolipase D/metabolismo , Receptores de Glutamato/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo
7.
Cell ; 137(4): 604-6, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19450509

RESUMO

Caspase-8 is activated at the plasma membrane by the death-inducing signaling complex (DISC). Jin et al. (2009) show that polyubiquitination of caspase-8, rather than targeting it for proteasomal degradation, is critical for sustaining caspase-8 activity after dissociation from the DISC.


Assuntos
Caspase 8/metabolismo , Proteínas Culina/metabolismo , Apoptose , Proteínas Adaptadoras de Sinalização de Receptores de Domínio de Morte/metabolismo , Humanos , Ubiquitinação
8.
J Pediatr Nurs ; 77: e242-e250, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38658303

RESUMO

PURPOSE: To determine how COVID-19 lockdown impacted physical activity (PA) levels, wellbeing, and diabetes management in children (aged 0-17 years) with type 1 diabetes (T1D), from the perspectives of their parent/guardian. DESIGN AND METHODS: This qualitative descriptive study is part of a larger, parallel mixed-methods design study, which incorporated a cross-sectional survey and semi-structured one-to-one interviews. Interviewees were recruited from the survey, which was distributed to parents of children/adolescents with T1D in the UK. Interviews explored diabetes management, mental and physical wellbeing, changes in PA levels, sleep quality before/during lockdown, and the effects of lockdown on the individual and their family. The interviews were transcribed and the data were analysed thematically. RESULTS: 14 interviews were conducted with parents. Thematic analysis generated a central theme of routine disruption, with four further themes on diabetes management routines, harnessing the opportunities of lockdown, weighing up risk, and variable impact on wellbeing. CONCLUSIONS: Maintaining or increasing PA during COVID-19 lockdown was associated with better diabetes management, sleep, and wellbeing for children/adolescents with T1D, despite significant disruption to established routines. Use of technology during the pandemic contributed positively to wellbeing. PRACTICE IMPLICATIONS: It is crucial to emphasize the significance of maintaining a well-structured routine when treating patients with type 1 diabetes. A consistent routine, incorporating regular physical exercise and good sleep hygiene, will help with managing overall diabetes control.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 1 , Exercício Físico , Pais , Pesquisa Qualitativa , Humanos , Diabetes Mellitus Tipo 1/psicologia , COVID-19/prevenção & controle , COVID-19/epidemiologia , Criança , Masculino , Adolescente , Feminino , Reino Unido , Pais/psicologia , Estudos Transversais , Pré-Escolar , Adaptação Psicológica , SARS-CoV-2 , Quarentena/psicologia , Lactente
9.
J Biol Chem ; 298(6): 101931, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35427646

RESUMO

Pyroptosis is a mechanism of inflammatory cell death mediated by the activation of the prolytic protein gasdermin D by caspase-1, caspase-4, and caspase-5 in human, and caspase-1 and caspase-11 in mouse. In addition, caspase-1 amplifies inflammation by proteolytic activation of cytokine interleukin-1ß (IL-1ß). Modern mammals of the order Carnivora lack the caspase-1 catalytic domain but express an unusual version of caspase-4 that can activate both gasdermin D and IL-1ß. Seeking to understand the evolutionary origin of this caspase, we utilized the large amount of data available in public databases to perform ancestral sequence reconstruction of an inflammatory caspase of a Carnivora ancestor. We expressed the catalytic domain of this putative ancestor in Escherichia coli, purified it, and compared its substrate specificity on synthetic and protein substrates to extant caspases. We demonstrated that it activates gasdermin D but has reduced ability to activate IL-1ß. Our reconstruction suggests that caspase-1 was lost in a Carnivora ancestor, perhaps upon a selective pressure for which the generation of biologically active IL-1ß by caspase-1 was detrimental. We speculate that later, a Carnivora encountered selective pressures that required the production of IL-1ß, and caspase-4 subsequently gained this activity. This hypothesis would explain why extant Carnivora possess an inflammatory caspase with caspase-1 catalytic function placed on a caspase-4 scaffold.


Assuntos
Caspases , Animais , Carnívoros/genética , Carnívoros/metabolismo , Caspase 1/genética , Caspase 1/metabolismo , Caspases/genética , Caspases/metabolismo , Escherichia coli/genética , Inflamação/genética , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Proteínas de Ligação a Fosfato/genética , Proteínas de Ligação a Fosfato/metabolismo , Piroptose/fisiologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Seleção Genética
10.
Mol Cell ; 77(5): 927-929, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-32142688
11.
Biochem J ; 479(14): 1533-1542, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35789254

RESUMO

A patient diagnosed with multiple myeloma, bicuspid aortic valve, and Von Hippel-Lindau syndrome underwent whole-exome sequencing seeking a unified genetic cause for these three pathologies. The patient possessed a single-point mutation of arginine to cysteine (R24C) in the N-terminal region(pro-domain) of matrix metalloproteinase 9 (MMP-9). The pro-domain interacts with the catalytic site of this enzyme rendering it inactive. MMP-9 has previously been associated with all three pathologies suffered by the patient. We hypothesized that the observed mutation in the pro-domain would influence the activity of this enzyme. We expressed recombinant versions of MMP-9 and an investigation of their biochemical properties revealed that MMP-9 R24C is a constitutively active zymogen. To our knowledge, this is the first example of a mutation that discloses catalytic activity in the pro-form in any of the 24 human MMPs.


Assuntos
Doença da Válvula Aórtica Bicúspide , Mieloma Múltiplo , Doença de von Hippel-Lindau , Mutação com Ganho de Função , Humanos , Metaloproteinase 9 da Matriz/genética , Mieloma Múltiplo/complicações , Mieloma Múltiplo/genética , Doença de von Hippel-Lindau/complicações , Doença de von Hippel-Lindau/genética
12.
Rheumatol Int ; 43(4): 627-638, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36125521

RESUMO

Patient-centered research should assess outcomes important to patients and include patient-reported outcome measures (PROMs) to assess health-related quality of life (HRQOL) domains. Using a well-known HRQOL framework (World Health Organization QOL, or WHOQOL), we reviewed established PROMs used with adults with different types of arthritis to evaluate their HRQOL domain coverage and psychometric evidence to help PROM users select measures and determine whether other measures should be validated and/or developed. Nineteen PROMs and 92 corresponding articles were reviewed to determine which HRQOL domains were assessed. To support a streamlined but rigorous review, we used a rating system based on criteria established in part through existing rubrics (e.g., OMERACT COSMIN). Psychometric properties were rated on a scale from 1 to 18, where 18 was strongest. We examined the intersection between level of domain coverage and extent of psychometric support. Measures most commonly assessed physical health and level of independence, while fewer assessed social relations, environment, and psychological health. No measures assessed spirituality and religion, which may be relevant depending on intended use. PROMs with higher psychometric evidence tended to assess a broader range of HRQOL domains. Rubric scores ranged from 3 to 16, with an average of 9.3. Prominent and psychometrically sound PROMs are available that cover many of the WHOQOL domains. While gaps exist in the domain of spirituality, future work should focus on refining optimal use of existing PROMs relevant for arthritis versus developing new measures. We provide guidance on selecting PROMs, to that end.


Assuntos
Artrite , Reumatologia , Humanos , Adulto , Qualidade de Vida , Medidas de Resultados Relatados pelo Paciente , Saúde Mental , Artrite/terapia , Psicometria , Inquéritos e Questionários
13.
PLoS Genet ; 16(5): e1008749, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32453742

RESUMO

Indonesia is the world's fourth most populous country, host to striking levels of human diversity, regional patterns of admixture, and varying degrees of introgression from both Neanderthals and Denisovans. However, it has been largely excluded from the human genomics sequencing boom of the last decade. To serve as a benchmark dataset of molecular phenotypes across the region, we generated genome-wide CpG methylation and gene expression measurements in over 100 individuals from three locations that capture the major genomic and geographical axes of diversity across the Indonesian archipelago. Investigating between- and within-island differences, we find up to 10.55% of tested genes are differentially expressed between the islands of Sumba and New Guinea. Variation in gene expression is closely associated with DNA methylation, with expression levels of 9.80% of genes correlating with nearby promoter CpG methylation, and many of these genes being differentially expressed between islands. Genes identified in our differential expression and methylation analyses are enriched in pathways involved in immunity, highlighting Indonesia's tropical role as a source of infectious disease diversity and the strong selective pressures these diseases have exerted on humans. Finally, we identify robust within-island variation in DNA methylation and gene expression, likely driven by fine-scale environmental differences across sampling sites. Together, these results strongly suggest complex relationships between DNA methylation, transcription, archaic hominin introgression and immunity, all jointly shaped by the environment. This has implications for the application of genomic medicine, both in critically understudied Indonesia and globally, and will allow a better understanding of the interacting roles of genomic and environmental factors shaping molecular and complex phenotypes.


Assuntos
Metilação de DNA , Etnicidade/genética , Interação Gene-Ambiente , Transcriptoma , Ilhas de CpG , Meio Ambiente , Epigênese Genética/fisiologia , Etnicidade/estatística & dados numéricos , Perfilação da Expressão Gênica/estatística & dados numéricos , Genética Populacional , Estudo de Associação Genômica Ampla/estatística & dados numéricos , Genômica/métodos , Humanos , Indonésia/epidemiologia , Ilhas/epidemiologia , Ilhas do Pacífico/epidemiologia , Linhagem , Fenótipo , Polimorfismo de Nucleotídeo Único , RNA-Seq
14.
Proc Natl Acad Sci U S A ; 117(18): 9952-9963, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32345717

RESUMO

Genetic polymorphisms in the region of the trimeric serine hydrolase high-temperature requirement 1 (HTRA1) are associated with increased risk of age-related macular degeneration (AMD) and disease progression, but the precise biological function of HtrA1 in the eye and its contribution to disease etiologies remain undefined. In this study, we have developed an HtrA1-blocking Fab fragment to test the therapeutic hypothesis that HtrA1 protease activity is involved in the progression of AMD. Next, we generated an activity-based small-molecule probe (ABP) to track target engagement in vivo. In addition, we used N-terminomic proteomic profiling in preclinical models to elucidate the in vivo repertoire of HtrA1-specific substrates, and identified substrates that can serve as robust pharmacodynamic biomarkers of HtrA1 activity. One of these HtrA1 substrates, Dickkopf-related protein 3 (DKK3), was successfully used as a biomarker to demonstrate the inhibition of HtrA1 activity in patients with AMD who were treated with the HtrA1-blocking Fab fragment. This pharmacodynamic biomarker provides important information on HtrA1 activity and pharmacological inhibition within the ocular compartment.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Anticorpos Anti-Idiotípicos/farmacologia , Atrofia Geográfica/tratamento farmacológico , Serina Peptidase 1 de Requerimento de Alta Temperatura A/genética , Degeneração Macular/tratamento farmacológico , Proteínas Adaptadoras de Transdução de Sinal/isolamento & purificação , Idoso , Animais , Anticorpos Anti-Idiotípicos/genética , Anticorpos Anti-Idiotípicos/imunologia , Biomarcadores/sangue , Progressão da Doença , Feminino , Predisposição Genética para Doença , Genótipo , Atrofia Geográfica/sangue , Atrofia Geográfica/genética , Atrofia Geográfica/imunologia , Serina Peptidase 1 de Requerimento de Alta Temperatura A/antagonistas & inibidores , Humanos , Fragmentos Fab das Imunoglobulinas/imunologia , Fragmentos Fab das Imunoglobulinas/farmacologia , Degeneração Macular/sangue , Degeneração Macular/genética , Degeneração Macular/imunologia , Masculino , Polimorfismo de Nucleotídeo Único/genética , Proteoma/genética , Proteoma/imunologia , Ratos , Retina/efeitos dos fármacos , Retina/imunologia , Retina/patologia , Bibliotecas de Moléculas Pequenas/farmacologia
15.
Int J Mol Sci ; 24(4)2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36835033

RESUMO

3-3'-Diindolylmethane (DIM) is a biologically active dimer derived from the endogenous conversion of indole-3-carbinol (I3C), a naturally occurring glucosinolate found in many cruciferous vegetables (i.e., Brassicaceae). DIM was the first pure androgen receptor antagonist isolated from the Brassicaceae family and has been recently investigated for its potential pharmacological use in prostate cancer prevention and treatment. Interestingly, there is evidence that DIM can also interact with cannabinoid receptors. In this context, by considering the well-known involvement of the endocannabinoid system in prostate cancer, we have pharmacologically characterized the properties of DIM on both CB1 and CB2 cannabinoid receptors in two human prostate cancer cell lines: PC3 (androgen-independent/androgen receptor negative) and LNCaP (androgen-dependent). In the PC3 cell line, DIM was able to activate CB2 receptors and potentially associated apoptotic pathways. On the other hand, although DIM was also able to activate CB2 receptors in the LNCaP cell line, no apoptotic effects were observed. Our evidence confirms that DIM is a CB2 receptor ligand and, moreover, it has a potential anti-proliferative effect on androgen-independent/androgen receptor-negative prostate cancer cells.


Assuntos
Brassicaceae , Neoplasias da Próstata , Receptor CB2 de Canabinoide , Humanos , Masculino , Androgênios/metabolismo , Brassicaceae/química , Linhagem Celular , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Receptor CB2 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/química
16.
Int J Mol Sci ; 24(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36674826

RESUMO

In this study, we have investigated a possible mechanism that enables CB1/M3 receptor cross-talk, using SH-SY5Y cells as a model system. Our results show that M3 receptor activation initiates signaling that rapidly upregulates the CNR1 gene, resulting in a greatly potentiated CB1 receptor response to agonists. Calcium homeostasis plays an essential intermediary role in this functional CB1/M3 receptor cross-talk. We show that M3 receptor-triggered calcium release greatly increases CB1 receptor expression via both transcriptional and translational activity, by enhancing CNR1 promoter activity. The co-expression of M3 and CB1 receptors in brain areas such as the nucleus accumbens and amygdala support the hypothesis that the altered synaptic plasticity observed after exposure to cannabinoids involves cross-talk with the M3 receptor subtype. In this context, M3 receptors and their interaction with the cannabinoid system at the transcriptional level represent a potential pharmacogenomic target not only for the develop of new drugs for addressing addiction and tolerance. but also to understand the mechanisms underpinning response stratification to cannabinoids.


Assuntos
Canabinoides , Neuroblastoma , Humanos , Receptor CB1 de Canabinoide/genética , Receptor CB1 de Canabinoide/metabolismo , Cálcio/metabolismo , Canabinoides/farmacologia , Canabinoides/metabolismo , Sinalização do Cálcio
17.
Trends Biochem Sci ; 43(10): 829-844, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30097385

RESUMO

Proteases are considered of major importance in biomedical research because of their crucial roles in health and disease. Their ability to hydrolyze their protein and peptide substrates at single or multiple sites, depending on their specificity, makes them unique among the enzymes. Understanding protease specificity is therefore crucial to understand their biology as well as to develop tools and drugs. Recent advancements in the fields of proteomics and chemical biology have improved our understanding of protease biology through extensive specificity profiling and identification of physiological protease substrates. There are growing efforts to transfer this knowledge into clinical modalities, but their success is often limited because of overlapping protease features, protease redundancy, and chemical tools lacking specificity. Herein, we discuss the current trends and challenges in protease research and how to exploit the growing information on protease specificities for understanding protease biology, as well as for development of selective substrates, cleavable linkers, and activity-based probes and for biomarker discovery.


Assuntos
Peptídeo Hidrolases/metabolismo , Biomarcadores/metabolismo , Conjuntos de Dados como Assunto , Humanos , Proteômica , Especificidade por Substrato
18.
Diabet Med ; 39(5): e14814, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35181926

RESUMO

AIMS: Many individuals with type 1 diabetes retain residual ß-cell function, with increased endogenous insulin secretion associated with reduced hyperglycaemia, hypoglycaemia and glycaemic variability. However, it is unknown when these improvements occur during the day. Dysglycaemia is common in overnight and postprandial periods and associated with diabetes complications. Therefore, this study aimed to determine the influence of residual ß-cell function upon nocturnal and postprandial glycaemic control in established type 1 diabetes. METHODS: Under free-living conditions, 66 participants wore a blinded continuous glucose monitor (CGM), kept a food diary, and completed a stimulated urine C-peptide creatinine (UCPCR) test. Nocturnal, and postprandial CGM outcomes (participant means and discrete event analysis) were compared between UCPCR groups: undetectable (Cpepund ), low (Cpeplow : 0.001-0.19 nmol/mmol) and high (Cpephigh : ≥0.2 nmol/mmol). RESULTS: Greater ß-cell function was associated with incremental improvements in glycaemia. Cpephigh spent significantly greater time in normoglycaemia than Cpepund overnight (76 ± 20% vs. 58 ± 20%, p = 0.005) and 0-300 mins postprandially (68 ± 22% vs. 51 ± 22%, p = 0.045), while also having reducing nocturnal variability (SD 1.12 ± 0.41 vs. 1.52 ± 0.43 mmol/L, p = 0.010). Analysis of individual events, controlling for diabetes duration, BMI, basal insulin, use of a continuous or flash glucose monitor and (for postprandial) meal type, carbohydrate and bolus insulin intake, replicated the group findings, additionally demonstrating Cpepund had increased hyperglycaemia versus Cpeplow overnight and increased postprandial hypoglycaemic events compared with Cpephigh . For all participants, breakfast had a significantly higher incremental area under the curve than lunch and dinner. CONCLUSIONS: Residual ß-cell function is associated with improved nocturnal and postprandial glycaemic control. These data may be of clinical importance for identifying specific periods and individuals where further glycaemic management strategies would be beneficial.


Assuntos
Diabetes Mellitus Tipo 1 , Hiperglicemia , Hipoglicemia , Glicemia/análise , Estudos Cross-Over , Diabetes Mellitus Tipo 1/tratamento farmacológico , Progressão da Doença , Humanos , Hiperglicemia/prevenção & controle , Insulina , Período Pós-Prandial
19.
Catheter Cardiovasc Interv ; 100(1): 133-142, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35535629

RESUMO

BACKGROUND: Mitral transcatheter edge-to-edge repair (MTEER) is an established therapeutic approach for mitral regurgitation (MR). Functional mitral regurgitation originating from atrial myopathy (A-FMR) has been described. OBJECTIVES: We sought to assess the clinical, echocardiographic and hemodynamic considerations in A-FMR patients undergoing MTEER. METHODS: From 2014 to 2020, patients undergoing MTEER for degenerative MR (DMR), functional MR (FMR), and mixed MR were assessed. A-FMR was defined by the presence of MR > moderate in severity; left ventricular (LV) ejection fraction (LVEF) ≥ 50%; and severe left atrial (LA) enlargement in the absence of LV dysfunction, leaflet pathology, or LV tethering. The diagnosis of A-FMR (vs. ventricular-FMR [V-FMR]) was confirmed by three independent echocardiographers. Baseline characteristics, procedural outcomes as well as clinical and echocardiographic follow-up are reported. Device success was defined as final MR grade ≤ moderate; MR reduction ≥1 grade; and final transmitral gradient <5 mmHg. RESULTS: 306 patients underwent MTEER, including DMR (62%), FMR (19%), and mixed MR (19%). FMR cases included 37 (63.8%) V-FMR and 21 (36.2%) A-FMR. Tricuspid regurgitation (≥ moderate) was higher in A-FMR (80.1%) compared to V-FMR (54%) and DMR (42%). Device success did not significantly differ between A-FMR and V-FMR (57% vs. 73%, p = 0.34) or DMR (57% vs. 64%, p = 1.0). The A-FMR cohort was less likely to achieve ≥3 grades of MR reduction compared to V-FMR (19% vs. 54%, p = 0.01) and DMR (19% vs. 49.7%, p = 0.01). Patients with V-FMR and DMR demonstrated significant reductions in mean left atrial pressure (LAP) and peak LA V-wave, though A-FMR did not (LAP -0.24 ± 4.9, p = 0.83; peak V-wave -1.76 ± 9.1, p = 0.39). In follow-up, echocardiographic and clinical outcomes were similar. CONCLUSIONS: In patients undergoing MTEER, A-FMR represents one-third of FMR cases. A-FMR demonstrates similar procedural success but blunted acute hemodynamic responses compared with DMR and V-FMR following MTEER. Dedicated studies specifically considering A-FMR are needed to discern the optimal therapeutic approaches.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
20.
Catheter Cardiovasc Interv ; 99(6): 1807-1816, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35066988

RESUMO

OBJECTIVES: To compare all-cause mortality in patients with mitral annulus calcification (MAC) and severe mitral valve dysfunction (MVD) who received standard mitral intervention versus no intervention. BACKGROUND: Patients with MAC often have high surgical risk due to advanced age, comorbidities, and technical challenges related to calcium. The impact of a mitral intervention on outcomes of patients with MAC and severe MVD is not well known. METHODS: Retrospective review of patients with MAC by transthoracic echocardiography (TTE) in 2015 at a single institution. Patients with severe mitral stenosis (MS) or regurgitation (MR) were analyzed and stratified into two groups: surgical or transcatheter intervention performed <1 year after the index TTE, and no or later intervention. The primary endpoint was all-cause mortality. RESULTS: Of 5502 patients with MAC, 357 had severe MVD (MS = 27%, MR = 73%). Of those, 108 underwent mitral intervention (surgery = 87; transcatheter = 21). They were younger (73 ± 11 vs. 76 ± 11 years, p < 0.01) and less frequently had cardiovascular diseases compared with no-intervention. Frequency in women was similar (45% vs. 50%, p = 0.44). During median follow-up of 3.2 years, the intervention group had higher estimated survival than those without intervention (80% vs. 72% at 1 year and 55% vs. 35% at 4 year, p < 0.01). Adjusted for age, eGFR, LVEF < 50%, and pulmonary hypertension, mitral intervention was an independent predictor of lower mortality (hazard ratio = 0.66, 95% confidence interval 0.43-0.99, p = 0.046). CONCLUSION: Patients with MAC and severe MVD who underwent mitral intervention <1 year from index TTE had lower mortality than those without intervention. Mitral intervention was independently associated with lower mortality.


Assuntos
Calcinose , Doenças das Valvas Cardíacas , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Estenose da Valva Mitral , Calcinose/diagnóstico por imagem , Calcinose/cirurgia , Feminino , Doenças das Valvas Cardíacas/cirurgia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/cirurgia , Estenose da Valva Mitral/complicações , Estenose da Valva Mitral/diagnóstico por imagem , Estenose da Valva Mitral/terapia , Estudos Retrospectivos , Resultado do Tratamento
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