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1.
Nat Commun ; 15(1): 8209, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39294132

RESUMO

CRISPR-based gene activation (CRISPRa) is a strategy for upregulating gene expression by targeting promoters or enhancers in a tissue/cell-type specific manner. Here, we describe an experimental framework that combines highly multiplexed perturbations with single-cell RNA sequencing (sc-RNA-seq) to identify cell-type-specific, CRISPRa-responsive cis-regulatory elements and the gene(s) they regulate. Random combinations of many gRNAs are introduced to each of many cells, which are then profiled and partitioned into test and control groups to test for effect(s) of CRISPRa perturbations of both enhancers and promoters on the expression of neighboring genes. Applying this method to a library of 493 gRNAs targeting candidate cis-regulatory elements in both K562 cells and iPSC-derived excitatory neurons, we identify gRNAs capable of specifically upregulating intended target genes and no other neighboring genes within 1 Mb, including gRNAs yielding upregulation of six autism spectrum disorder (ASD) and neurodevelopmental disorder (NDD) risk genes in neurons. A consistent pattern is that the responsiveness of individual enhancers to CRISPRa is restricted by cell type, implying a dependency on either chromatin landscape and/or additional trans-acting factors for successful gene activation. The approach outlined here may facilitate large-scale screens for gRNAs that activate genes in a cell type-specific manner.


Assuntos
Sistemas CRISPR-Cas , Elementos Facilitadores Genéticos , Análise de Célula Única , Humanos , Análise de Célula Única/métodos , Células K562 , Elementos Facilitadores Genéticos/genética , Regiões Promotoras Genéticas/genética , RNA Guia de Sistemas CRISPR-Cas/genética , Transtorno do Espectro Autista/genética , Neurônios/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética
2.
Neurol Ther ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251561

RESUMO

INTRODUCTION: Lymphocyte depletion via anti-CD52 monoclonal antibody (mAb) therapy is an effective treatment strategy for relapsing-remitting multiple sclerosis (MS) but is associated with infusion/injection-associated reactions (IARs) and autoimmune-related adverse events (AEs). Gatralimab is a next-generation humanized anti-CD52 mAb. METHODS: Two first-in-human trials were conducted in participants with progressive MS to assess the pharmacodynamics, pharmacokinetics, and safety of gatralimab administered via subcutaneous (SC) and intravenous (IV) routes, and to determine the effect of different comedication regimes on IARs to SC gatralimab. A Phase 1 trial (NCT02282826) included double-blind, placebo-controlled sequential ascending single IV (1, 3.5, and 12 mg) and SC (12, 36, and 60 mg) dose groups. A Phase 1b trial (NCT02977533) involved five groups who received SC gatralimab (36, 48, or 60 mg) and different comedications. A long-term safety (LTS) study (NCT02313285) examined safety and pharmacodynamics over 4 years. RESULTS: Gatralimab produced depletion of lymphocytes (dose-dependently) and CD4+ regulatory T cells, with partial repopulation to normal values by approximately 12 months. Peak serum gatralimab concentrations followed dose-proportionality and were delayed by 6.0-7.5 days following SC administration. Treatment-emergent AEs, including IARs, were reported for most participants but were generally of mild or moderate severity, and treatment-emergent serious AEs were mostly MS-related. Methylprednisolone and antihistamine comedications were associated with reduced incidence of fevers and skin and subcutaneous tissue AEs, respectively. During the LTS study, one participant (3.0%) experienced an autoimmune-related AE (Basedow's disease), and subsequently died from pulmonary sepsis deemed unrelated to gatralimab by the investigator. CONCLUSIONS: These data show that gatralimab achieves the desired pharmacodynamic effect of lymphocyte depletion followed by repopulation, and has an acceptable safety profile, including low risk of non-MS autoimmunity. Although gatralimab is no longer in development for MS, insights from these trials may inform the development of comedication regimes of future anti-CD52 mAbs and subcutaneous formulations of other lymphocyte-depleting mAbs. TRIAL REGISTRATION: NCT02282826, NCT02977533, NCT02313285.

3.
Prenat Diagn ; 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39218781

RESUMO

Recent advances in gene therapy, particularly for single-gene disorders (SGDs), have led to significant progress in developing innovative precision medicine approaches that hold promise for treating conditions such as primary hydrocephalus (CH), which is characterized by increased cerebrospinal fluid (CSF) volumes and cerebral ventricular dilation as a result of impaired brain development, often due to genetic causes. CH is a significant contributor to childhood morbidity and mortality and a driver of healthcare costs. In many cases, prenatal ultrasound can readily identify ventriculomegaly as early as 14-20 weeks of gestation, with severe cases showing poor neurodevelopmental outcomes. Postnatal surgical approaches, such as ventriculoperitoneal shunts, do not address the underlying genetic causes, have high complication rates, and result in a marginal improvement of neurocognitive deficits. Prenatal somatic cell gene therapy (PSCGT) promises a novel approach to conditions such as CH by targeting genetic mutations in utero, potentially improving long-term outcomes. To better understand the pathophysiology, genetic basis, and molecular pathomechanisms of CH, we conducted a scoping review of the literature that identified over 160 published genes linked to CH. Mutations in L1CAM, TRIM71, MPDZ, and CCDC88C play a critical role in neural stem cell development, subventricular zone architecture, and the maintenance of the neural stem cell niche, driving the development of CH. Early prenatal interventions targeting these genes could curb the development of the expected CH phenotype, improve neurodevelopmental outcomes, and possibly limit the need for surgical approaches. However, further research is needed to establish robust genotype-phenotype correlations and develop safe and effective PSCGT strategies for CH.

4.
Lancet Healthy Longev ; : 100622, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39270688

RESUMO

BACKGROUND: Robust evidence for interventions to improve health-related quality of life (HRQoL) in people who receive a kidney transplant is scarce. We aimed to assess the effects of a lifestyle intervention in this context. METHODS: We conducted a multicentre, open-label, parallel-group, randomised controlled trial among people who have received a kidney transplant. Participants from six hospitals across the Netherlands were randomly assigned 1:1:1 by an independent company into: usual care, exercise, and exercise plus diet. The exercise intervention encompassed two phases, a 3-month supervised exercise programme (twice weekly) followed by 12 months of lifestyle coaching, with 15 months of additional dietary counselling (12 sessions) for the exercise plus diet group. The primary outcome was HRQoL-domain physical functioning, assessed using the 36-item Short Form Survey at 15 months. FINDINGS: From Oct 12, 2010 to Nov 18, 2016, 221 participants who had received a kidney transplant (138 [62%] male and 83 [38%] female, with a mean age of 52·5 [SD 13·5] years, who were a median of 5·5 [IQR 3·6-8·4] months post-transplant) were included and randomly assigned to usual care (n=74), exercise intervention (n=77), and exercise plus diet intervention (n=70). In the intention-to-treat analyses, at 15 months post-baseline, no significant differences in HRQoL-domain physical functioning were found for the exercise group (5·3 arbitrary units, 95% CI -4·2 to 14·9; p=0·27), and the exercise plus diet group (5·9 arbitrary units, -4·1 to 16·0; p=0·25) compared with control. Safety outcomes showed no safety concerns. After 3 months of supervised exercise intervention, HRQoL-domain physical functioning improved in the exercise group (7·3 arbitrary units, 95% CI 1·2 to 13·3; p=0·018) but not in the exercise plus diet group (5·8 arbitrary units, -0·5 to 12·1; p=0·072). INTERPRETATION: A lifestyle intervention is safe and feasible in people who have received kidney transplants, paving the way for lifestyle intervention studies in other multimorbid populations with polypharmacy. However, improving HRQoL for people who have received a kidney transplant is challenging. The lifestyle interventions in the current study did not show significant improvements in HRQoL at the end of the study at the total group level. FUNDING: Dutch Kidney Foundation, Innovation Fund of the Dutch Medical Insurance Companies, and University Medical Center Groningen.

5.
Nat Cell Biol ; 26(9): 1571-1584, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39117797

RESUMO

Caloric restriction and intermittent fasting prolong the lifespan and healthspan of model organisms and improve human health. The natural polyamine spermidine has been similarly linked to autophagy enhancement, geroprotection and reduced incidence of cardiovascular and neurodegenerative diseases across species borders. Here, we asked whether the cellular and physiological consequences of caloric restriction and fasting depend on polyamine metabolism. We report that spermidine levels increased upon distinct regimens of fasting or caloric restriction in yeast, flies, mice and human volunteers. Genetic or pharmacological blockade of endogenous spermidine synthesis reduced fasting-induced autophagy in yeast, nematodes and human cells. Furthermore, perturbing the polyamine pathway in vivo abrogated the lifespan- and healthspan-extending effects, as well as the cardioprotective and anti-arthritic consequences of fasting. Mechanistically, spermidine mediated these effects via autophagy induction and hypusination of the translation regulator eIF5A. In summary, the polyamine-hypusination axis emerges as a phylogenetically conserved metabolic control hub for fasting-mediated autophagy enhancement and longevity.


Assuntos
Autofagia , Caenorhabditis elegans , Restrição Calórica , Jejum , Longevidade , Espermidina , Autofagia/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Espermidina/metabolismo , Espermidina/farmacologia , Animais , Humanos , Caenorhabditis elegans/metabolismo , Fatores de Iniciação de Peptídeos/metabolismo , Fatores de Iniciação de Peptídeos/genética , Fator de Iniciação de Tradução Eucariótico 5A , Drosophila melanogaster/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Camundongos , Masculino , Camundongos Endogâmicos C57BL
6.
Clin Nutr ESPEN ; 63: 787-795, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39154804

RESUMO

BACKGROUND: Protein intake is known to be associated with muscle mass, health-related quality of life (HRQoL), and mortality in patients with stage 5 chronic kidney disease undergoing dialysis. However, most studies evaluated protein intake based on 24 h dietary recall or food frequency questionnaire, and these methods are prone to bias. Therefore, this study aimed to evaluate the association of objectively measured protein intake with muscle mass and strength, HRQoL, and mortality. METHODS: Dietary protein intake was calculated based on the combined (urinary and dialysate) urea excretion rate according to the Maroni formula and indexed to body weight. Muscle mass was calculated based on the combined dialysate and urinary creatinine excretion rate, and muscle strength was assessed by handgrip strength. HRQoL was based on the Short Form 36. Linear and Cox regression were used for the analyses. RESULTS: We included 59 hemodialysis patients (mean age 65 ± 15 years, 37% female, median hemodialysis vintage 15 [6-39] months). Mean protein intake was 0.82 ± 0.23 g/kg/day, and 76% had a low protein intake (<1.0 g/kg/day). Higher protein intake was independently associated with higher muscle mass (Standardized beta (St. ß) [95% confidence interval (95%CI) = 0.56 [0.34 to 0.78]) and higher scores on the physical functioning domain of HRQoL (St. ß [95%CI] = 0.49 [0.25 to 0.73]), but not with muscle strength (St. ß [95%CI] = 0.17 [-0.10 to 0.43]). During a median follow-up of 21.6 [8.6-36.6] months, 16 (27.1%) patients died. Higher protein intake was associated with lower mortality risk (hazard ratio [95%CI] = 0.34 [0.16-0.73]). This association remained significant after adjustment for potential confounders. CONCLUSIONS: Protein intake is independently associated with muscle mass, physical functioning domain of HRQOL, and mortality. Clinicians and dietitians should closely monitor the protein intake of hemodialysis patients.

7.
HGG Adv ; 5(4): 100345, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39182167

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental disorder (NDD) that affects approximately 4% of males and 1% of females in the United States. While causes of ASD are multi-factorial, single rare genetic variants contribute to around 20% of cases. Here, we report a case series of seven unrelated probands (6 males, 1 female) with ASD or another variable NDD phenotype attributed to de novo heterozygous loss of function or missense variants in the gene LARP1 (La ribonucleoprotein 1). LARP1 encodes an RNA-binding protein that post-transcriptionally regulates the stability and translation of thousands of mRNAs, including those regulating cellular metabolism and metabolic plasticity. Using lymphocytes collected and immortalized from an index proband who carries a truncating variant in one allele of LARP1, we demonstrated that lower cellular levels of LARP1 protein cause reduced rates of aerobic respiration and glycolysis. As expression of LARP1 increases during neurodevelopment, with higher levels in neurons and astrocytes, we propose that LARP1 haploinsufficiency contributes to ASD or related NDDs through attenuated metabolic activity in the developing fetal brain.

8.
Gut ; 73(10): 1650-1661, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-38955400

RESUMO

OBJECTIVE: Gut microbiome composition is associated with multiple diseases, but relatively little is known about its relationship with long-term outcome measures. While gut dysbiosis has been linked to mortality risk in the general population, the relationship with overall survival in specific diseases has not been extensively studied. In the current study, we present results from an in-depth analysis of the relationship between gut dysbiosis and all-cause and cause-specific mortality in the setting of solid organ transplant recipients (SOTR). DESIGN: We analysed 1337 metagenomes derived from faecal samples of 766 kidney, 334 liver, 170 lung and 67 heart transplant recipients part of the TransplantLines Biobank and Cohort-a prospective cohort study including extensive phenotype data with 6.5 years of follow-up. To analyze gut dysbiosis, we included an additional 8208 metagenomes from the general population of the same geographical area (northern Netherlands). Multivariable Cox regression and a machine learning algorithm were used to analyse the association between multiple indicators of gut dysbiosis, including individual species abundances, and all-cause and cause-specific mortality. RESULTS: We identified two patterns representing overall microbiome community variation that were associated with both all-cause and cause-specific mortality. The gut microbiome distance between each transplantation recipient to the average of the general population was associated with all-cause mortality and death from infection, malignancy and cardiovascular disease. A multivariable Cox regression on individual species abundances identified 23 bacterial species that were associated with all-cause mortality, and by applying a machine learning algorithm, we identified a balance (a type of log-ratio) consisting of 19 out of the 23 species that were associated with all-cause mortality. CONCLUSION: Gut dysbiosis is consistently associated with mortality in SOTR. Our results support the observations that gut dysbiosis is associated with long-term survival. Since our data do not allow us to infer causality, more preclinical research is needed to understand mechanisms before we can determine whether gut microbiome-directed therapies may be designed to improve long-term outcomes.


Assuntos
Disbiose , Microbioma Gastrointestinal , Transplante de Órgãos , Humanos , Disbiose/mortalidade , Feminino , Masculino , Pessoa de Meia-Idade , Transplante de Órgãos/efeitos adversos , Estudos Prospectivos , Causas de Morte , Transplantados/estatística & dados numéricos , Adulto , Fezes/microbiologia , Países Baixos/epidemiologia , Metagenoma , Idoso
9.
Biol Psychiatry Glob Open Sci ; 4(4): 100321, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38957312

RESUMO

Background: Sex-differential biology may contribute to the consistently male-biased prevalence of autism spectrum disorder (ASD). Gene expression differences between males and females in the brain can indicate possible molecular and cellular mechanisms involved, although transcriptomic sex differences during human prenatal cortical development have been incompletely characterized, primarily due to small sample sizes. Methods: We performed a meta-analysis of sex-differential expression and co-expression network analysis in 2 independent bulk RNA sequencing datasets generated from cortex of 273 prenatal donors without known neuropsychiatric disorders. To assess the intersection between neurotypical sex differences and neuropsychiatric disorder biology, we tested for enrichment of ASD-associated risk genes and expression changes, neuropsychiatric disorder risk genes, and cell type markers within identified sex-differentially expressed genes (sex-DEGs) and sex-differential co-expression modules. Results: We identified 101 significant sex-DEGs, including Y-chromosome genes, genes impacted by X-chromosome inactivation, and autosomal genes. Known ASD risk genes, implicated by either common or rare variants, did not preferentially overlap with sex-DEGs. We identified 1 male-specific co-expression module enriched for immune signaling that is unique to 1 input dataset. Conclusions: Sex-differential gene expression is limited in prenatal human cortex tissue, although meta-analysis of large datasets allows for the identification of sex-DEGs, including autosomal genes that encode proteins involved in neural development. Lack of sex-DEG overlap with ASD risk genes in the prenatal cortex suggests that sex-differential modulation of ASD symptoms may occur in other brain regions, at other developmental stages, or in specific cell types, or may involve mechanisms that act downstream from mutation-carrying genes.


Males are more commonly diagnosed with autism spectrum disorder than females, and sex differences in brain development may contribute to this difference. Here, we define differences in gene expression patterns between males and females in human prenatal brain tissue from 273 donors to identify 101 genes that are expressed at different levels in males and females and gene sets that show sex-specific expression correlations. Genes with autism-associated DNA variants and genes with altered expression in autism do not preferentially overlap with sex-differential genes, suggesting that sex-differential biology may influence autism risk mechanisms in other brain regions, at other developmental stages, or in specific cell types.

10.
ACS Chem Biol ; 19(7): 1604-1615, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38980123

RESUMO

Targeted protein degradation (TPD) is a therapeutic approach that leverages the cell's natural machinery to degrade targets instead of inhibiting them. This is accomplished by using mono- or bifunctional small molecules designed to induce the proximity of target proteins and E3 ubiquitin ligases, leading to ubiquitination and subsequent proteasome-dependent degradation of the target. One of the most significant attributes of the TPD approach is its proposed catalytic mechanism of action, which permits substoichiometric exposure to achieve the desired pharmacological effects. However, apart from one in vitro study, studies supporting the catalytic mechanism of degraders are largely inferred based on potency. A more comprehensive understanding of the degrader catalytic mechanism of action can help aspects of compound development. To address this knowledge gap, we developed a workflow for the quantitative measurement of the catalytic rate of degraders in cells. Comparing a selective and promiscuous BTK degrader, we demonstrate that both compounds function as efficient catalysts of BTK degradation, with the promiscuous degrader exhibiting faster rates due to its ability to induce more favorable ternary complexes. By leveraging computational modeling, we show that the catalytic rate is highly dynamic as the target is depleted from cells. Further investigation of the promiscuous kinase degrader revealed that the catalytic rate is a better predictor of optimal degrader activity toward a specific target compared to degradation magnitude alone. In summary, we present a versatile method for mapping the catalytic activity of any degrader for TPD in cells.


Assuntos
Proteólise , Humanos , Tirosina Quinase da Agamaglobulinemia/metabolismo , Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Complexo de Endopeptidases do Proteassoma/metabolismo
11.
Eur J Heart Fail ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39015086

RESUMO

AIM: Senescence is a major risk factor for heart failure (HF), and insulin-like growth factor-binding protein-7 (IGFBP7) has been identified as an important senescence-inducing factor. The aim of this study was to examine the value of baseline and repeat IGFBP7 measurements in predicting future HF among community-dwelling Dutch adults from the Prevention of Renal and Vascular End-stage Disease (PREVEND) study. METHODS AND RESULTS: Individuals without prevalent HF who attended PREVEND visits 2 and 4 median of 5.1 years apart (25th-75th percentile, 4.9-5.2) with measurements of IGFBP7 were included. We used Cox proportional hazards models to investigate the association between IGFBP7 and HF incidence. A total of 6125 participants attending visit 2 (mean ± standard deviation [SD] age 53.1 ± 12.2 years; 3151 [51.4%] men) were followed for a median of 8.4 (7.8-8.9) years, and 194 participants (3.2%) developed incident HF. Median baseline IGFBP7 concentration was 87.0 (75.1-97.3) ng/ml, and baseline IGFBP7 levels were significantly associated with risk for incident HF (HF risk factors adjusted hazard ratio [HR] per 1 SD change in log-transformed IGFBP7: 1.22, 95% confidence interval [CI] 1.03-1.46). Baseline IGFBP7 was also significantly associated with incident HF in individuals with N-terminal pro-B-type natriuretic peptide <125 ng/L. Among 3879 participants attending both visits 2 and 4 (mean ± SD age 57.5 ± 11.3 years; 1952 [50.3%] men), 93 individuals developed HF (after visit 4) during a median follow-up of 3.2 (2.8-3.9) years. Median increase in IGFBP7 concentration between visits was 0.68 (-7.09 to 8.36) ng/ml, and changes in IGFBP7 levels were significantly associated with risk for incident HF (HF risk factors adjusted HR per 1 SD change in log-transformed IGFBP7: 1.68, 95% CI 1.19-2.36). CONCLUSIONS: Both baseline as well as repeat IGFBP7 measurements provide information about the risk of developing HF.

12.
Brief Bioinform ; 25(4)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38966948

RESUMO

Variants in cis-regulatory elements link the noncoding genome to human pathology; however, detailed analytic tools for understanding the association between cell-level brain pathology and noncoding variants are lacking. CWAS-Plus, adapted from a Python package for category-wide association testing (CWAS), enhances noncoding variant analysis by integrating both whole-genome sequencing (WGS) and user-provided functional data. With simplified parameter settings and an efficient multiple testing correction method, CWAS-Plus conducts the CWAS workflow 50 times faster than CWAS, making it more accessible and user-friendly for researchers. Here, we used a single-nuclei assay for transposase-accessible chromatin with sequencing to facilitate CWAS-guided noncoding variant analysis at cell-type-specific enhancers and promoters. Examining autism spectrum disorder WGS data (n = 7280), CWAS-Plus identified noncoding de novo variant associations in transcription factor binding sites within conserved loci. Independently, in Alzheimer's disease WGS data (n = 1087), CWAS-Plus detected rare noncoding variant associations in microglia-specific regulatory elements. These findings highlight CWAS-Plus's utility in genomic disorders and scalability for processing large-scale WGS data and in multiple-testing corrections. CWAS-Plus and its user manual are available at https://github.com/joonan-lab/cwas/ and https://cwas-plus.readthedocs.io/en/latest/, respectively.


Assuntos
Sequenciamento Completo do Genoma , Humanos , Sequenciamento Completo do Genoma/métodos , Doença de Alzheimer/genética , Estudo de Associação Genômica Ampla/métodos , Transtorno do Espectro Autista/genética , Variação Genética , Software , Cromatina/genética , Cromatina/metabolismo , Genoma Humano
13.
J Clin Med ; 13(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38999257

RESUMO

Metformin is the most widely used drug in type 2 diabetes. Regular metformin use has been associated with changes in concentrations of amino acids. In the present study, we used valid stable-isotope labeled GC-MS methods to measure amino acids and metabolites, including creatinine as well as malondialdehyde (MDA), as an oxidative stress biomarker in plasma, urine, and dialysate samples in a patient at admission to the intensive care unit and during renal replacement treatment because of metformin-associated lactic acidosis (MALA, 21 mM lactate, 175 µM metformin). GC-MS revealed lower concentrations of amino acids in plasma, normal concentrations of the nitric oxide (NO) metabolites nitrite and nitrate, and normal concentrations of MDA. Renal tubular reabsorption rates were altered on admission. The patient received renal replacement therapy over 50 to 70 h of normalized plasma amino acid concentrations and their tubular reabsorption, as well as the tubular reabsorption of nitrite and nitrate. This study indicates that GC-MS is a versatile analytical tool to measure different classes of physiological inorganic and organic substances in complex biological samples in clinical settings such as MALA.

14.
J Med Virol ; 96(7): e29806, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39007420

RESUMO

Optimization of individual immunosuppression, which reduces the risks of both graft loss and patients' death, is considered the best approach to improve long-term outcomes of renal transplantation. Torque Teno Virus (TTV) DNAemia has emerged as a potential biomarker reflecting the depth of therapeutic immunosuppression during the initial year post-transplantation. However, its efficacy in long-term monitoring remains uncertain. In a cohort study involving 34 stable kidney transplant recipients and 124 healthy volunteers, we established lower and upper TTV DNAemia thresholds (3.75-5.1 log10 cp/mL) correlating with T-cell activatability, antibody response against flu vaccine, and risk for subsequent serious infections or cancer over 50 months. Validation in an independent cohort of 92 recipients confirmed that maintaining TTV DNAemia within this range in >50% of follow-up time points was associated with reduced risks of complications due to inadequate immunosuppression, including de novo DSA, biopsy-proven antibody-mediated rejection, graft loss, infections, or cancer. Multivariate analysis highlighted "in-target" TTV DNAemia as the sole independent variable significantly linked to decreased risk for long-term complications due to inadequate immunosuppression (odds ratio [OR]: 0.27 [0.09-0.77]; p = 0.019). Our data suggest that the longitudinal monitoring of TTV DNAemia in kidney transplant recipients could help preventing the long-term complications due to inadequate immunosuppression.


Assuntos
Infecções por Vírus de DNA , DNA Viral , Terapia de Imunossupressão , Transplante de Rim , Torque teno virus , Transplantados , Humanos , Torque teno virus/genética , Transplante de Rim/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , DNA Viral/sangue , Adulto , Infecções por Vírus de DNA/virologia , Infecções por Vírus de DNA/sangue , Infecções por Vírus de DNA/imunologia , Terapia de Imunossupressão/efeitos adversos , Estudos Longitudinais , Idoso , Rejeição de Enxerto , Imunossupressores/uso terapêutico , Imunossupressores/efeitos adversos , Estudos de Coortes , Viremia
15.
Arterioscler Thromb Vasc Biol ; 44(8): 1884-1894, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38899469

RESUMO

BACKGROUND: Vascular calcification is associated with increased mortality in patients with cardiovascular disease. Secondary calciprotein particles are believed to play a causal role in the pathophysiology of vascular calcification. The maturation time (T50) of calciprotein particles provides a measure of serum calcification propensity. We compared T50 between patients with ST-segment-elevated myocardial infarction and control subjects and studied the association of T50 with cardiovascular risk factors and outcome. METHODS: T50 was measured by nephelometry in 347 patients from the GIPS-III trial (Metabolic Modulation With Metformin to Reduce Heart Failure After Acute Myocardial Infarction: Glycometabolic Intervention as Adjunct to Primary Coronary Intervention in ST Elevation Myocardial Infarction: a Randomized Controlled Trial) and in 254 matched general population controls from PREVEND (Prevention of Renal and Vascular End-Stage Disease). We also assessed the association between T50 and left ventricular ejection fraction, as well as infarct size, the incidence of ischemia-driven reintervention during 5 years of follow-up, and serum nitrite as a marker of endothelial dysfunction. RESULTS: Patients with ST-segment-elevated myocardial infarction had a significantly lower T50 (ie, higher serum calcification propensity) compared with controls (T50: 289±63 versus 338±56 minutes; P<0.001). In patients with ST-segment-elevated myocardial infarction, lower T50 was associated with female sex, lower systolic blood pressure, lower total cholesterol, lower LDL (low-density lipoprotein) cholesterol, lower triglycerides, and higher HDL (high-density lipoprotein) cholesterol but not with circulating nitrite or nitrate. Ischemia-driven reintervention was associated with higher LDL (P=0.03) and had a significant interaction term for T50 and sex (P=0.005), indicating a correlation between ischemia-driven reintervention and T50 above the median in men and below the median in women, between 150 days and 5 years of follow-up. CONCLUSIONS: Serum calcification propensity is increased in patients with ST-segment-elevated myocardial infarction compared with the general population, and its contribution is more pronounced in women than in men. Its lack of/inverse association with nitrite and blood pressure confirms T50 to be orthogonal to traditional cardiovascular disease risk factors. Lower T50 was associated with a more favorable serum lipid profile, suggesting the involvement of divergent pathways of calcification stress and lipid stress in the pathophysiology of myocardial infarction.


Assuntos
Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Biomarcadores/sangue , Fatores de Risco de Doenças Cardíacas , Calcificação Vascular/sangue , Calcificação Vascular/fisiopatologia , Medição de Risco , Fatores de Risco , Estudos de Casos e Controles , Fatores de Tempo , Função Ventricular Esquerda , Volume Sistólico
16.
Cell Rep ; 43(6): 114329, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38850535

RESUMO

Many autism spectrum disorder (ASD)-associated genes act as transcriptional regulators (TRs). Chromatin immunoprecipitation sequencing (ChIP-seq) was used to identify the regulatory targets of ARID1B, BCL11A, FOXP1, TBR1, and TCF7L2, ASD-associated TRs in the developing human and mouse cortex. These TRs shared substantial overlap in the binding sites, especially within open chromatin. The overlap within a promoter region, 1-2,000 bp upstream of the transcription start site, was highly predictive of brain-expressed genes. This signature was observed in 96 out of 102 ASD-associated genes. In vitro CRISPRi against ARID1B and TBR1 delineated downstream convergent biology in mouse cortical cultures. After 8 days, NeuN+ and CALB+ cells were decreased, GFAP+ cells were increased, and transcriptomic signatures correlated with the postmortem brain samples from individuals with ASD. We suggest that functional convergence across five ASD-associated TRs leads to shared neurodevelopmental outcomes of haploinsufficient disruption.


Assuntos
Encéfalo , Humanos , Animais , Camundongos , Encéfalo/metabolismo , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/metabolismo , Transtorno do Espectro Autista/patologia , Transtorno Autístico/genética , Transtorno Autístico/metabolismo , Transtorno Autístico/patologia , Regulação da Expressão Gênica , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Loci Gênicos
17.
J Cachexia Sarcopenia Muscle ; 15(4): 1528-1538, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38898741

RESUMO

BACKGROUND: Serum creatinine is used as initial test to derive eGFR and confirmatory testing with serum cystatin C is recommended when creatinine-based eGFR is considered less accurate due to deviant muscle mass. Low muscle mass is associated with increased risk of premature mortality. However, the associations of serum creatinine and cystatin C with muscle mass and mortality remain unclear and require further investigation to better inform clinical decision-making. METHODS: We included 8437 community-dwelling adults enrolled in the Dutch PREVEND study and 5033 in the US NHANES replication cohort. Associations of serum creatinine and/or cystatin C with muscle mass surrogates and mortality were quantified with linear and Cox proportional hazards regression, respectively. Missing observations in covariates were multiply imputed using Substantive Model Compatible Fully Conditional Specification. RESULTS: Mean (SD) age of PREVEND and NHANES participants (50% and 48% male) were 49.8 (12.6) and 48.7 (18.7) years, respectively. Median (Q1-Q3) serum creatinine and cystatin C were 71 (61-80) and 80 (62-88) µmol/L and 0.87 (0.78-0.98) and 0.91 (0.80-1.10) mg/L, respectively. Higher serum creatinine was associated with greater muscle mass, while serum cystatin C was not associated with muscle mass. Adjusting both markers for each other strengthened the positive relationship between serum creatinine and muscle mass and revealed an inverse association between serum cystatin C and muscle mass. In the PREVEND cohort, 1636 (19%) deaths were registered over a median follow-up of 12.9 (5.8-16.3) years with a 10-year mortality rate (95% CI) of 7.6% (7.1-8.2%). In the NHANES, 1273 (25%) deaths were registered over a median follow-up of 17.9 (17.3-18.5) years with a 10-year mortality rate of 13.8% (12.8-14.7%). Both markers were associated with increased mortality. Notably, when adjusted for each other, higher serum creatinine was associated with decreased mortality, while the association between serum cystatin C and increased mortality strengthened. The shapes of the associations in the PREVEND study and NHANES were almost identical. CONCLUSIONS: The strong association between serum creatinine and muscle mass challenges its reliability as GFR marker, necessitating a more cautious approach in its clinical use. The minimal association between serum cystatin C and muscle mass supports its increased use as a more reliable alternative in routine clinical practice.


Assuntos
Biomarcadores , Creatinina , Cistatina C , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores/sangue , Estudos de Coortes , Creatinina/sangue , Cistatina C/sangue , Mortalidade , Músculo Esquelético
18.
Amino Acids ; 56(1): 42, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869518

RESUMO

Creatine is a natural nitrogenous organic acid that is integral to energy metabolism and crucial for proper cell functioning. The kidneys are involved in the first step of creatine production. With kidney transplantation being the gold-standard treatment for end-stage kidney disease, kidney transplant recipients (KTR) may be at risk of impaired creatine synthesis. We aimed to compare creatine homeostasis between KTR and controls. Plasma and urine concentrations of arginine, glycine, guanidinoacetate, creatine and creatinine were measured in 553 KTR and 168 healthy controls. Creatine intake was assessed using food frequency questionnaires. Iothalamate-measured GFR data were available in subsets of 157 KTR and 167 controls. KTR and controls had comparable body weight, height and creatine intake (all P > 0.05). However, the total creatine pool was 14% lower in KTR as compared to controls (651 ± 178 vs. 753 ± 239 mmol, P < 0.001). The endogenous creatine synthesis rate was 22% lower in KTR as compared to controls (7.8 ± 3.0 vs. 10.0 ± 4.1 mmol per day, P < 0.001). Despite lower GFR, the plasma guanidinoacetate and creatine concentrations were 21% and 41% lower in KTR as compared to controls (both P < 0.001). Urinary excretion of guanidinoacetate and creatine were 66% and 59% lower in KTR as compared to controls (both P < 0.001). In KTR, but not in controls, a higher measured GFR was associated with a higher endogenous creatine synthesis rate (std. beta: 0.21, 95% CI: 0.08; 0.33; P = 0.002), as well as a higher total creatine pool (std. beta: 0.22, 95% CI: 0.11; 0.33; P < 0.001). These associations were fully mediated (93% and 95%; P < 0.001) by urinary guanidinoacetate excretion which is consistent with production of the creatine precursor guanidinoacetate as rate-limiting factor. Our findings highlight that KTR have a disturbed creatine homeostasis as compared to controls. Given the direct relationship of measured GFR with endogenous creatine synthesis rate and the total creatine pool, creatine supplementation might be beneficial in KTR with low kidney function.Trial registration ID: NCT02811835.Trial registration URL: https://clinicaltrials.gov/ct2/show/NCT02811835 .


Assuntos
Creatina , Homeostase , Transplante de Rim , Rim , Humanos , Creatina/urina , Creatina/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Rim/metabolismo , Glicina/análogos & derivados , Glicina/urina , Glicina/metabolismo , Glicina/sangue , Taxa de Filtração Glomerular , Transplantados , Estudos de Casos e Controles , Creatinina/urina , Creatinina/sangue
19.
Am J Surg ; : 115784, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38824053

RESUMO

BACKGROUND: Cognitive impairment affects nearly half of vascular surgery patients, but its association with postoperative outcomes remains poorly understood. This study explores the link between preoperative cognitive performance and postoperative complications, including postoperative delirium, in vascular surgery patients. METHODS: A prospective cohort study was conducted on vascular surgery patients aged ≥65. Preoperative cognitive performance was assessed using the Montreal Cognitive Assessment, and postoperative complications were evaluated using the Comprehensive Complication Index. The association was analyzed through multivariable logistic regression. RESULTS: Among 110 patients (18.2 â€‹% female, mean age 73.8 â€‹± â€‹5.7 years), cognitive impairment was evident in 48.2 â€‹%. Of the participants, 29 (26.3 â€‹%) experienced postoperative complications, among which 11 (10 â€‹%) experienced postoperative delirium. The adjusted odds ratio for the association between cognitive performance and postoperative complications was 1.19 (95 â€‹% CI 1.02-1.38; p â€‹= â€‹0.02). CONCLUSION: Worse preoperative cognitive performance correlated with increased odds of postoperative complications and postoperative delirium in vascular surgery patients.

20.
Int J Mol Sci ; 25(11)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38892218

RESUMO

Liver transplant recipients (LTRs) have lower long-term survival rates compared with the general population. This underscores the necessity for developing biomarkers to assess post-transplantation mortality. Here we compared plasma trimethylamine-N-oxide (TMAO) levels with those in the general population, investigated its determinants, and interrogated its association with all-cause mortality in stable LTRs. Plasma TMAO was measured in 367 stable LTRs from the TransplantLines cohort (NCT03272841) and in 4837 participants from the population-based PREVEND cohort. TMAO levels were 35% higher in LTRs compared with PREVEND participants (4.3 vs. 3.2 µmol/L, p < 0.001). Specifically, TMAO was elevated in LTRs with metabolic dysfunction-associated steatotic liver disease, alcohol-associated liver disease, and polycystic liver disease as underlying etiology (p < 0.001 for each). Among LTRs, TMAO levels were independently associated with eGFR (std. ß = -0.43, p < 0.001) and iron supplementation (std. ß = 0.13, p = 0.008), and were associated with mortality (29 deaths during 8.6 years follow-up; log-rank test p = 0.017; hazard ratio of highest vs. lowest tertile 4.14, p = 0.007). In conclusion, plasma TMAO is likely elevated in stable LTRs, with impaired eGFR and iron supplementation as potential contributory factors. Our preliminary findings raise the possibility that plasma TMAO could contribute to increased mortality risk in such patients, but this need to be validated through a series of rigorous and methodical studies.


Assuntos
Biomarcadores , Transplante de Fígado , Metilaminas , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores/sangue , Transplante de Fígado/efeitos adversos , Metilaminas/sangue , Transplantados
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