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1.
Cell ; 186(23): 4996-5014.e24, 2023 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-37949056

RESUMEN

A formal demonstration that mammalian pluripotent stem cells possess preimplantation embryonic cell-like (naive) pluripotency is the generation of chimeric animals through early embryo complementation with homologous cells. Whereas such naive pluripotency has been well demonstrated in rodents, poor chimerism has been achieved in other species including non-human primates due to the inability of the donor cells to match the developmental state of the host embryos. Here, we have systematically tested various culture conditions for establishing monkey naive embryonic stem cells and optimized the procedures for chimeric embryo culture. This approach generated an aborted fetus and a live chimeric monkey with high donor cell contribution. A stringent characterization pipeline demonstrated that donor cells efficiently (up to 90%) incorporated into various tissues (including the gonads and placenta) of the chimeric monkeys. Our results have major implications for the study of primate naive pluripotency and genetic engineering of non-human primates.


Asunto(s)
Células Madre Embrionarias , Ingeniería Genética , Haplorrinos , Animales , Femenino , Embarazo , Haplorrinos/genética , Nacimiento Vivo , Mamíferos , Células Madre Pluripotentes , Primates , Ingeniería Genética/métodos
2.
Cell ; 185(10): 1777-1792.e21, 2022 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-35512705

RESUMEN

Spatially resolved transcriptomic technologies are promising tools to study complex biological processes such as mammalian embryogenesis. However, the imbalance between resolution, gene capture, and field of view of current methodologies precludes their systematic application to analyze relatively large and three-dimensional mid- and late-gestation embryos. Here, we combined DNA nanoball (DNB)-patterned arrays and in situ RNA capture to create spatial enhanced resolution omics-sequencing (Stereo-seq). We applied Stereo-seq to generate the mouse organogenesis spatiotemporal transcriptomic atlas (MOSTA), which maps with single-cell resolution and high sensitivity the kinetics and directionality of transcriptional variation during mouse organogenesis. We used this information to gain insight into the molecular basis of spatial cell heterogeneity and cell fate specification in developing tissues such as the dorsal midbrain. Our panoramic atlas will facilitate in-depth investigation of longstanding questions concerning normal and abnormal mammalian development.


Asunto(s)
Organogénesis , Transcriptoma , Animales , ADN/genética , Embrión de Mamíferos , Femenino , Perfilación de la Expresión Génica/métodos , Mamíferos/genética , Ratones , Organogénesis/genética , Embarazo , Análisis de Secuencia de ARN/métodos , Análisis de la Célula Individual/métodos , Transcriptoma/genética
3.
Nature ; 629(8010): 154-164, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38649488

RESUMEN

Muscle atrophy and functional decline (sarcopenia) are common manifestations of frailty and are critical contributors to morbidity and mortality in older people1. Deciphering the molecular mechanisms underlying sarcopenia has major implications for understanding human ageing2. Yet, progress has been slow, partly due to the difficulties of characterizing skeletal muscle niche heterogeneity (whereby myofibres are the most abundant) and obtaining well-characterized human samples3,4. Here we generate a single-cell/single-nucleus transcriptomic and chromatin accessibility map of human limb skeletal muscles encompassing over 387,000 cells/nuclei from individuals aged 15 to 99 years with distinct fitness and frailty levels. We describe how cell populations change during ageing, including the emergence of new populations in older people, and the cell-specific and multicellular network features (at the transcriptomic and epigenetic levels) associated with these changes. On the basis of cross-comparison with genetic data, we also identify key elements of chromatin architecture that mark susceptibility to sarcopenia. Our study provides a basis for identifying targets in the skeletal muscle that are amenable to medical, pharmacological and lifestyle interventions in late life.


Asunto(s)
Envejecimiento , Músculo Esquelético , Análisis de la Célula Individual , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Envejecimiento/genética , Envejecimiento/patología , Envejecimiento/fisiología , Núcleo Celular/metabolismo , Cromatina/metabolismo , Cromatina/genética , Susceptibilidad a Enfermedades , Epigénesis Genética , Fragilidad/genética , Fragilidad/patología , Músculo Esquelético/citología , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Atrofia Muscular/genética , Atrofia Muscular/patología , Sarcopenia/genética , Sarcopenia/patología , Transcriptoma
4.
Nature ; 613(7942): 169-178, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36544018

RESUMEN

Tissue regeneration requires coordination between resident stem cells and local niche cells1,2. Here we identify that senescent cells are integral components of the skeletal muscle regenerative niche that repress regeneration at all stages of life. The technical limitation of senescent-cell scarcity3 was overcome by combining single-cell transcriptomics and a senescent-cell enrichment sorting protocol. We identified and isolated different senescent cell types from damaged muscles of young and old mice. Deeper transcriptome, chromatin and pathway analyses revealed conservation of cell identity traits as well as two universal senescence hallmarks (inflammation and fibrosis) across cell type, regeneration time and ageing. Senescent cells create an aged-like inflamed niche that mirrors inflammation associated with ageing (inflammageing4) and arrests stem cell proliferation and regeneration. Reducing the burden of senescent cells, or reducing their inflammatory secretome through CD36 neutralization, accelerates regeneration in young and old mice. By contrast, transplantation of senescent cells delays regeneration. Our results provide a technique for isolating in vivo senescent cells, define a senescence blueprint for muscle, and uncover unproductive functional interactions between senescent cells and stem cells in regenerative niches that can be overcome. As senescent cells also accumulate in human muscles, our findings open potential paths for improving muscle repair throughout life.


Asunto(s)
Envejecimiento , Senescencia Celular , Inflamación , Músculo Esquelético , Regeneración , Nicho de Células Madre , Anciano , Animales , Humanos , Ratones , Envejecimiento/metabolismo , Envejecimiento/fisiología , Senescencia Celular/fisiología , Inflamación/metabolismo , Inflamación/fisiopatología , Músculo Esquelético/fisiología , Músculo Esquelético/fisiopatología , Células Madre/fisiología , Fibrosis/fisiopatología , Nicho de Células Madre/fisiología , Transcriptoma , Cromatina/genética , Gerociencia
5.
Nature ; 605(7909): 315-324, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35314832

RESUMEN

After fertilization, the quiescent zygote experiences a burst of genome activation that initiates a short-lived totipotent state. Understanding the process of totipotency in human cells would have broad applications. However, in contrast to in mice1,2, demonstration of the time of zygotic genome activation or the eight-cell (8C) stage in in vitro cultured human cells has not yet been reported, and the study of embryos is limited by ethical and practical considerations. Here we describe a transgene-free, rapid and controllable method for producing 8C-like cells (8CLCs) from human pluripotent stem cells. Single-cell analysis identified key molecular events and gene networks associated with this conversion. Loss-of-function experiments identified fundamental roles for DPPA3, a master regulator of DNA methylation in oocytes3, and TPRX1, a eutherian totipotent cell homeobox (ETCHbox) family transcription factor that is absent in mice4. DPPA3 induces DNA demethylation throughout the 8CLC conversion process, whereas TPRX1 is a key executor of 8CLC gene networks. We further demonstrate that 8CLCs can produce embryonic and extraembryonic lineages in vitro or in vivo in the form of blastoids5 and complex teratomas. Our approach provides a resource to uncover the molecular process of early human embryogenesis.


Asunto(s)
Embrión de Mamíferos , Desarrollo Embrionario , Células Madre Pluripotentes , Cigoto , Humanos , Proteínas Cromosómicas no Histona/genética , Embrión de Mamíferos/citología , Proteínas de Homeodominio/genética , Células Madre Pluripotentes/citología , Factores de Transcripción/genética , Cigoto/citología
6.
Nature ; 604(7907): 723-731, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35418686

RESUMEN

Studying tissue composition and function in non-human primates (NHPs) is crucial to understand the nature of our own species. Here we present a large-scale cell transcriptomic atlas that encompasses over 1 million cells from 45 tissues of the adult NHP Macaca fascicularis. This dataset provides a vast annotated resource to study a species phylogenetically close to humans. To demonstrate the utility of the atlas, we have reconstructed the cell-cell interaction networks that drive Wnt signalling across the body, mapped the distribution of receptors and co-receptors for viruses causing human infectious diseases, and intersected our data with human genetic disease orthologues to establish potential clinical associations. Our M. fascicularis cell atlas constitutes an essential reference for future studies in humans and NHPs.


Asunto(s)
Macaca fascicularis , Transcriptoma , Animales , Comunicación Celular , Macaca fascicularis/genética , Receptores Virales/genética , Transcriptoma/genética , Vía de Señalización Wnt
7.
J Intern Med ; 295(4): 557-568, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38111091

RESUMEN

BACKGROUND: Effects of intensive blood pressure (BP) control on cognitive outcomes in patients with excess orthostatic BP changes are unclear. We aimed to evaluate whether orthostatic BP changes modified the effects of BP intervention on cognitive impairment. METHODS: We analyzed 8547 participants from the Systolic Blood Pressure Intervention Trial Memory and cognition IN Decreased Hypertension. Associations between orthostatic BP changes and incident cognitive outcomes were evaluated by restricted cubic spline curves based on Cox models. The interactions between orthostatic BP changes and intensive BP intervention were assessed. RESULTS: The U-shaped associations were observed between baseline orthostatic systolic BP changes and cognitive outcomes. However, there were insignificant interactions between either change in orthostatic systolic BP (P for interaction = 0.81) or diastolic BP (P for interaction = 0.32) and intensive BP intervention for the composite outcome of probable dementia or mild cognitive impairment (MCI). The hazard ratio of intensive versus standard target for the composite cognitive outcome was 0.82 (95% CI 0.50-1.35) in those with an orthostatic systolic BP reduction of >20 mmHg and 0.41 (95% CI 0.21-0.80) in those with an orthostatic systolic BP increase of >20 mmHg. Results were similar for probable dementia and MCI. The annual changes in global cerebral blood flow (P for interaction = 0.86) consistently favored intensive BP treatment across orthostatic systolic BP changes. CONCLUSION: Intensive BP control did not have a deteriorating effect on cognitive outcomes among hypertensive patients experiencing significant postural BP changes.


Asunto(s)
Disfunción Cognitiva , Demencia , Hipertensión , Hipotensión Ortostática , Humanos , Presión Sanguínea , Cognición , Hipertensión/tratamiento farmacológico , Hipotensión Ortostática/psicología
8.
Pacing Clin Electrophysiol ; 47(1): 58-65, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38010824

RESUMEN

BACKGROUND: Sodium-glucose cotransporter 2 inhibitors (SGLT2i) is reported to reduce incident atrial fibrillation (AF) in patients with or without diabetes; however, its cardiovascular (CV) benefit for AF patients remains unclear. SS AIMS: To investigate the effect of SGLT2i on the incidence of CV events in patients with AF. METHODS: Six randomized controlled trials (RCTs) assessing the effects of SGLT2i on CV outcomes in patients with or without AF were included (PROSPERO: CRD 42023431535). The primary endpoint was the composite outcome of heart failure (HF) hospitalization and CV death. Additionally, we assessed the effects of treatment in prespecified subgroups on HF hospitalization, CV death, and all-cause mortality. RESULTS: Among 38,529 participants from all trials, 5018 patients with AF were treated with SGLT2i. The follow-up period of these trials ranged from 2.3 to 3.3 years. SGLT2i treatment was significantly associated with the risk reduction of primary endpoint in patients with AF (risk ratio [RR] 0.81, 95% confidence interval [CI] 0.74-0.88; p < 0.001), consistent with the finding in the general population (p for interaction = 0.76). SGLT2i was also associated with a consistent reduction in the risk of HF hospitalization in patients with AF (RR 0.76, 95% CI 0.69-0.84; p < 0.001) or not (RR 0.72, 95% CI 0.64-0.80; p < 0.0001), with no statistical difference between them (p for interaction = 0.41). Meta-regression further revealed no significant association between the prevalence of HF with reduced ejection fraction or diabetes and the effect size of SGLT2i. CONCLUSIONS: The treatment effects of SGLT2i were associated with a lower incidence of CV events, especially HF hospitalization, in patients with AF.


Asunto(s)
Fibrilación Atrial , Diabetes Mellitus , Insuficiencia Cardíaca , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Humanos , Fibrilación Atrial/tratamiento farmacológico , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/epidemiología
10.
Am Heart J ; 260: 34-43, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36813122

RESUMEN

BACKGROUND: In randomized studies, the strategy of pulmonary vein antral isolation (PVI) plus linear ablation has failed to increase success rates for persistent atrial fibrillation (PeAF) ablation when compared with PVI alone. Peri-mitral reentry related atrial tachycardia due to incomplete linear block is an important cause of clinical failures of a first ablation procedure. Ethanol infusion (EI) into the vein of Marshall (EI-VOM) has been demonstrated to facilitate a durable mitral isthmus linear lesion. OBJECTIVE: This trial is designed to compare arrhythmia-free survival between PVI and an ablation strategy termed upgraded '2C3L' for the ablation of PeAF. STUDY DESIGN: The PROMPT-AF study (clinicaltrials.gov 04497376) is a prospective, multicenter, open-label, randomized trial using a 1:1 parallel-control approach. Patients (n = 498) undergoing their first catheter ablation of PeAF will be randomized to either the upgraded '2C3L' arm or PVI arm in a 1:1 fashion. The upgraded '2C3L' technique is a fixed ablation approach consisting of EI-VOM, bilateral circumferential PVI, and 3 linear ablation lesion sets across the mitral isthmus, left atrial roof, and cavotricuspid isthmus. The follow-up duration is 12 months. The primary end point is freedom from atrial arrhythmias of >30 seconds, without antiarrhythmic drugs, in 12 months after the index ablation procedure (excluding a blanking period of 3 months). CONCLUSIONS: The PROMPT-AF study will evaluate the efficacy of the fixed '2C3L' approach in conjunction with EI-VOM, compared with PVI alone, in patients with PeAF undergoing de novo ablation.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Venas Pulmonares , Humanos , Fibrilación Atrial/cirugía , Venas Pulmonares/cirugía , Estudios Prospectivos , Atrios Cardíacos/cirugía , Etanol , Ablación por Catéter/métodos , Resultado del Tratamiento , Recurrencia
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