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1.
Cell ; 187(3): 764-781.e14, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38306985

RESUMO

Pregnancy induces dramatic metabolic changes in females; yet, the intricacies of this metabolic reprogramming remain poorly understood, especially in primates. Using cynomolgus monkeys, we constructed a comprehensive multi-tissue metabolome atlas, analyzing 273 samples from 23 maternal tissues during pregnancy. We discovered a decline in metabolic coupling between tissues as pregnancy progressed. Core metabolic pathways that were rewired during primate pregnancy included steroidogenesis, fatty acid metabolism, and arachidonic acid metabolism. Our atlas revealed 91 pregnancy-adaptive metabolites changing consistently across 23 tissues, whose roles we verified in human cell models and patient samples. Corticosterone and palmitoyl-carnitine regulated placental maturation and maternal tissue progenitors, respectively, with implications for maternal preeclampsia, diabetes, cardiac hypertrophy, and muscle and liver regeneration. Moreover, we found that corticosterone deficiency induced preeclampsia-like inflammation, indicating the atlas's potential clinical value. Overall, our multi-tissue metabolome atlas serves as a framework for elucidating the role of metabolic regulation in female health during pregnancy.


Assuntos
Metabolômica , Gravidez , Animais , Feminino , Humanos , Gravidez/metabolismo , Corticosterona/metabolismo , Metaboloma/fisiologia , Placenta/metabolismo , Pré-Eclâmpsia , Primatas/metabolismo
2.
Cell ; 186(10): 2078-2091.e18, 2023 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-37172562

RESUMO

Neural tube (NT) defects arise from abnormal neurulation and result in the most common birth defects worldwide. Yet, mechanisms of primate neurulation remain largely unknown due to prohibitions on human embryo research and limitations of available model systems. Here, we establish a three-dimensional (3D) prolonged in vitro culture (pIVC) system supporting cynomolgus monkey embryo development from 7 to 25 days post-fertilization. Through single-cell multi-omics analyses, we demonstrate that pIVC embryos form three germ layers, including primordial germ cells, and establish proper DNA methylation and chromatin accessibility through advanced gastrulation stages. In addition, pIVC embryo immunofluorescence confirms neural crest formation, NT closure, and neural progenitor regionalization. Finally, we demonstrate that the transcriptional profiles and morphogenetics of pIVC embryos resemble key features of similarly staged in vivo cynomolgus and human embryos. This work therefore describes a system to study non-human primate embryogenesis through advanced gastrulation and early neurulation.


Assuntos
Defeitos do Tubo Neural , Neurulação , Técnicas de Cultura de Tecidos , Animais , Humanos , Blastocisto , Embrião de Mamíferos , Desenvolvimento Embrionário , Macaca fascicularis , Defeitos do Tubo Neural/genética , Defeitos do Tubo Neural/patologia , Técnicas de Cultura de Tecidos/métodos
3.
Nature ; 612(7941): 732-738, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36517595

RESUMO

Our understanding of human early development is severely hampered by limited access to embryonic tissues. Due to their close evolutionary relationship with humans, nonhuman primates are often used as surrogates to understand human development but currently suffer from a lack of in vivo datasets, especially from gastrulation to early organogenesis during which the major embryonic cell types are dynamically specified. To fill this gap, we collected six Carnegie stage 8-11 cynomolgus monkey (Macaca fascicularis) embryos and performed in-depth transcriptomic analyses of 56,636 single cells. Our analyses show transcriptomic features of major perigastrulation cell types, which help shed light on morphogenetic events including primitive streak development, somitogenesis, gut tube formation, neural tube patterning and neural crest differentiation in primates. In addition, comparative analyses with mouse embryos and human embryoids uncovered conserved and divergent features of perigastrulation development across species-for example, species-specific dependency on Hippo signalling during presomitic mesoderm differentiation-and provide an initial assessment of relevant stem cell models of human early organogenesis. This comprehensive single-cell transcriptome atlas not only fills the knowledge gap in the nonhuman primate research field but also serves as an invaluable resource for understanding human embryogenesis and developmental disorders.


Assuntos
Gastrulação , Macaca fascicularis , Organogênese , Análise de Célula Única , Animais , Humanos , Camundongos , Gastrulação/genética , Macaca fascicularis/embriologia , Macaca fascicularis/genética , Organogênese/genética , Corpos Embrioides , Perfilação da Expressão Gênica , Linha Primitiva/citologia , Linha Primitiva/embriologia , Tubo Neural/citologia , Tubo Neural/embriologia , Crista Neural/citologia , Crista Neural/embriologia , Via de Sinalização Hippo , Mesoderma/citologia , Mesoderma/embriologia , Células-Tronco
4.
Anal Chem ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39056433

RESUMO

Qualitative and quantitative analysis of Raman spectroscopy is a widely used nondestructive analytical technique in many fields. It utilizes the Raman scattering effect of lasers to obtain molecular vibration information on samples. By comparison with the Raman spectra of standard substances, qualitative and quantitative analyses can be achieved on unknown samples. However, current Raman spectroscopy analysis algorithms still have many drawbacks. They struggled to handle quantitative analysis between different instruments. Their prediction accuracy for concentration is generally low, with poor robustness. Therefore, this study addresses these deficiencies by designing the cross instrument-sparse Bayesian learning (CI-SBL) Raman spectroscopy analysis algorithm. CI-SBL can facilitate spectroscopic analysis between different instruments through the cross instrument module. CI-SBL converts data from portable instruments into data from scientific instruments, with high similarity between the converted spectrum and the spectrum from the scientific instruments reaching 98.6%. The similarity between the raw portable instrument spectrum and the scientific instrument spectrum is often lower than 90%. The cross instrument effect of the CI-SBL is remarkable. Moreover, CI-SBL employs sparse Bayesian learning (SBL) as the core module for analysis. Through multiple iterations, the SBL algorithm effectively identified various components within mixtures. In experiments, CI-SBL can achieve a qualitative accuracy of 100% for the majority of binary and multicomponent mixtures. On the other hand, the previous Raman spectroscopy analysis algorithms predominantly yield a qualitative accuracy below 80% for the same data. Additionally, CI-SBL incorporates a quantitative module to calculate the concentration of each component within the mixed samples. In the experiment, the quantification error for all substances was below 3%, with the majority of the substances exhibiting an error of approximately 1%. These experimental results illustrate that CI-SBL significantly enhances the accuracy of qualitative judgment of mixture spectra and the prediction of mixture concentrations compared with previous Raman spectroscopy analysis algorithms. Furthermore, the cross instrument module of CI-SBL allows for a flexible handling of data acquired from different instruments.

5.
Nat Methods ; 20(12): 1855-1858, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38057510
6.
Cell Biol Int ; 41(6): 639-650, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28328017

RESUMO

Alzheimer's disease (AD) is an incurable neurodegenerative disease and many types of stem cells have been used in AD therapy with some favorable effects. In this study, we investigated the potential therapeutical effects of human dental pulp stem cells (hDPSCs) on AD cellular model which established by okadaic acid (OA)-induced damage to human neuroblastoma cell line, SH-SY5Y, in vitro for 24 h. After confirmed the AD cellular model, the cells were co-culture with hDPSCs by transwell co-culture system till 24 h for treatment. Then the cytomorphology of the hDPSCs-treated cells were found to restore gradually with re-elongation of retracted dendrites. Meanwhile, Cell Counting Kit-8 assay and Hoechst 33258 staining showed that hDPSCs caused significant increase in the viability and decrease in apoptosis of the model cells, respectively. Observation of DiI labeling also exhibited the prolongation dendrites in hDPSCs-treated cells which were obviously different from the retraction dendrites in AD model cells. Furthermore, specific staining of α-tubulin and F-actin demonstrated that the hDPSCs-treated cells had the morphology of restored neurons, with elongated dendrites, densely arranged microfilaments, and thickened microtubular fibrils. In addition, results from western blotting revealed that phosphorylation at Ser 396 of Tau protein was significantly suppressed by adding of hDPSCs. These results indicate that hDPSCs may promote regeneration of damaged neuron cells in vitro model of AD and may serve as a useful cell source for treatment of AD.


Assuntos
Células-Tronco Adultas/citologia , Doença de Alzheimer/terapia , Polpa Dentária/transplante , Células-Tronco Adultas/metabolismo , Doença de Alzheimer/metabolismo , Diferenciação Celular/fisiologia , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Técnicas de Cocultura/métodos , Polpa Dentária/citologia , Polpa Dentária/metabolismo , Humanos , Modelos Biológicos , Neuroblastoma/metabolismo , Neurônios/metabolismo , Neurônios/fisiologia , Cultura Primária de Células/métodos , Transplante de Células-Tronco
7.
Cell Stem Cell ; 31(7): 945-946, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38971145

RESUMO

Dattani et al.1 developed a method for inducing hypoblast-like cells from human naive pluripotent stem cells. They elucidated the requirement for FGF signaling in human hypoblast specialization at a specific time window, which was previously controversial.


Assuntos
Fatores de Crescimento de Fibroblastos , Transdução de Sinais , Humanos , Fatores de Crescimento de Fibroblastos/metabolismo , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/citologia , Diferenciação Celular
8.
Talanta ; 275: 126138, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38677164

RESUMO

Raman spectroscopy is a general and non-destructive detection technique that can obtain detailed information of the chemical structure of materials. In the past, when using chemometric algorithms to analyze the Raman spectra of mixtures, the challenges of complex spectral overlap and noise often limited the accurate identification of components. The emergence of deep learning has introduced a novel approach to qualitative analysis of mixed Raman spectra. In this paper, we propose a deep learning-based Raman spectroscopy qualitative analysis algorithm (RST) by borrowing the ideas of convolutional neural network and Transformer. By transforming the Raman spectrum into 64 word vectors, the contribution weights of each word vector to the components are obtained. For the 75 spectral data used for validation, the positive identification rate can reach 100.00 %, the recall rate can reach 99.3 %, the average identification score can reach 9.51, and it is applicable to the fields of Raman and surface-enhanced Raman spectroscopy. Furthermore, compared with traditional CNN models, RST has excellent accuracy and robustness in identifying components in complex mixtures. The model's interpretability has been enhanced, aiding in a deeper understanding of spectroscopic learning patterns for future analysis of more complex mixtures.

9.
PeerJ ; 11: e14440, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36643631

RESUMO

Background: Plasma S100A1 protein is a novel inflammatory biomarker associated with acute myocardial infarction and neurodegenerative disease's pathophysiological mechanisms. This study aimed to determine the levels of this protein in patients with acute ischemic stroke early in the disease progression and to investigate its role in the pathogenesis of acute ischemic stroke. Methods: A total of 192 participants from hospital stroke centers were collected for the study. Clinically pertinent data were recorded. The volume of the cerebral infarction was calculated according to the Pullicino formula. Multivariate logistic regression analysis was used to select independent influences. ROC curve was used to analyze the diagnostic value of AIS and TIA. The correlation between S100A1, NF-κB p65, and IL-6 levels and cerebral infarction volume was detected by Pearson correlation analysis. Results: There were statistically significant differences in S100A1, NF-κB p65, and IL-6 among the AIS,TIA, and PE groups (S100A1, [230.96 ± 39.37] vs [185.85 ± 43.24] vs [181.47 ± 27.39], P < 0.001; NF-κB p65, [3.99 ± 0.65] vs [3.58 ± 0.74] vs [3.51 ± 0.99], P = 0.001; IL-6, [13.32 ± 1.57] vs [11.61 ± 1.67] vs [11.42 ± 2.34], P < 0.001). Multivariate logistic regression analysis showed that S100A1 might be an independent predictive factor for the diagnosis of disease (P < 0.001). The AUC of S100A1 for diagnosis of AIS was 0.818 (P < 0.001, 95% CI [0.749-0.887], cut off 181.03, Jmax 0.578, Se 95.0%, Sp 62.7%). The AUC of S100A1 for diagnosis of TIA was 0.720 (P = 0.001, 95% CI [0.592-0.848], cut off 150.14, Jmax 0.442, Se 50.0%, Sp 94.2%). There were statistically significant differences in S100A1, NF-κB p65, and IL-6 among the SCI,MCI, and LCI groups (S100A1, [223.98 ± 40.21] vs [225.42 ± 30.92] vs [254.25 ± 37.07], P = 0.001; NF-κB p65, [3.88 ± 0.66] vs [3.85 ± 0.64] vs [4.41 ± 0.45], P < 0.001; IL-6, [13.27 ± 1.65] vs [12.77 ± 1.31] vs [14.00 ± 1.40], P = 0.007). Plasma S100A1, NF-κB p65, and IL-6 were significantly different from cerebral infarction volume (S100A1, r = 0.259, P = 0.002; NF-κB p65, r = 0.316, P < 0.001; IL-6, r = 0.177, P = 0.036). There was a positive correlation between plasma S100A1 and IL-6 with statistical significance (R = 0.353, P < 0.001). There was no significant positive correlation between plasma S100A1 and NF-κB p65 (R < 0.3), but there was statistical significance (R = 0.290, P < 0.001). There was a positive correlation between IL-6 and NF-κB p65 with statistical significance (R = 0.313, P < 0.001). Conclusion: S100A1 might have a better diagnostic efficacy for AIS and TIA. S100A1 was associated with infarct volume in AIS, and its level reflected the severity of acute cerebral infarction to a certain extent. There was a correlation between S100A1 and IL-6 and NF-κB p65, and it was reasonable to speculate that this protein might mediate the inflammatory response through the NF-κB pathway during the pathophysiology of AIS.


Assuntos
Ataque Isquêmico Transitório , AVC Isquêmico , Doenças Neurodegenerativas , Proteínas S100 , Humanos , Infarto Cerebral/diagnóstico , Interleucina-6 , Ataque Isquêmico Transitório/diagnóstico , AVC Isquêmico/sangue , AVC Isquêmico/diagnóstico , NF-kappa B/metabolismo , Estudos Prospectivos , Proteínas S100/sangue
10.
Nat Genet ; 55(1): 130-143, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36539615

RESUMO

In mammals, DNA 5-hydroxymethylcytosine (5hmC) is involved in methylation reprogramming during early embryonic development. Yet, to what extent 5hmC participates in genome-wide methylation reprogramming remains largely unknown. Here, we characterize the 5hmC landscapes in mouse early embryos and germ cells with parental allele specificity. DNA hydroxymethylation was most strongly correlated with DNA demethylation as compared with de novo or maintenance methylation in zygotes, while 5hmC was targeted to particular de novo methylated sites in postimplantation epiblasts. Surprisingly, DNA replication was also required for 5hmC generation, especially in the female pronucleus. More strikingly, aberrant nuclear localization of Dnmt1/Uhrf1 in mouse zygotes due to maternal deficiency of Nlrp14 led to defects in DNA-replication-coupled passive demethylation and impaired 5hmC deposition, revealing the divergency between genome-wide 5-methylcytosine (5mC) maintenance and Tet-mediated oxidation. In summary, our work provides insights and a valuable resource for the study of epigenetic regulation in early embryo development.


Assuntos
5-Metilcitosina , Metilação de DNA , Animais , Feminino , Camundongos , 5-Metilcitosina/metabolismo , Metilação de DNA/genética , Epigênese Genética , Desenvolvimento Embrionário/genética , Zigoto/metabolismo , Mamíferos , DNA/genética , DNA/metabolismo , Citosina/metabolismo
11.
Cell Death Dis ; 14(5): 321, 2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-37173309

RESUMO

With the expansion of the aging population, age-associated sarcopenia (AAS) has become a severe clinical disease of the elderly and a key challenge for healthy aging. Regrettably, no approved therapies currently exist for treating AAS. In this study, clinical-grade human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) were administrated to two classic mouse models (SAMP8 mice and D-galactose-induced aging mice), and their effects on skeletal muscle mass and function were investigated by behavioral tests, immunostaining, and western blotting. Core data results showed that hUC-MSCs significantly restored skeletal muscle strength and performance in both mouse models via mechanisms including raising the expression of crucial extracellular matrix proteins, activating satellite cells, enhancing autophagy, and impeding cellular aging. For the first time, the study comprehensively evaluates and demonstrates the preclinical efficacy of clinical-grade hUC-MSCs for AAS in two mouse models, which not only provides a novel model for AAS, but also highlights a promising strategy to improve and treat AAS and other age-associated muscle diseases. This study comprehensively evaluates the preclinical efficacy of clinical-grade hUC-MSCs in treating age-associated sarcopenia (AAS), and demonstrates that hUC-MSCs restore skeletal muscle strength and performance in two AAS mouse models via raising the expression of extracellular matrix proteins, activating satellite cells, enhancing autophagy, and impeding cellular aging, which highlights a promising strategy for AAS and other age-associated muscle diseases.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Sarcopenia , Humanos , Camundongos , Animais , Idoso , Diferenciação Celular , Sarcopenia/terapia , Músculo Esquelético , Células-Tronco Mesenquimais/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Transplante de Células-Tronco Mesenquimais/métodos , Cordão Umbilical
12.
Cell Prolif ; 56(5): e13492, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37199067

RESUMO

The interactions between extra-embryonic tissues and embryonic tissues are crucial to ensure proper early embryo development. However, the understanding of the crosstalk between the embryonic tissues and extra-embryonic tissues is lacking, mainly due to ethical restrictions, difficulties in obtaining natural human embryos, and lack of appropriate in vitro models. Here by aggregating human embryonic stem cells (hESCs) with human trophoblast stem cells (hTSCs), we revealed the hESCs robustly self-organized into a unique asymmetric structure which the primitive streak (PS) like cells exclusively distributed at the distal end to the TS-compartment, and morphologically flattened cells, presumed to be the extra-embryonic mesoderm cells (EXMC) like cells, were induced at the proximal end to hTSCs. Our study revealed two potential roles of extra-embryonic trophectoderm in regulating the proper PS formation during gastrulation and EXMCs induction from the human epiblast.


Assuntos
Gástrula , Trofoblastos , Humanos , Gástrula/fisiologia , Camadas Germinativas , Diferenciação Celular , Células-Tronco
13.
Dev Cell ; 58(9): 806-821.e7, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37054708

RESUMO

Supporting healthy pregnancy outcomes requires a comprehensive understanding of the cellular hierarchy and underlying molecular mechanisms in the primate placenta during gestation. Here, we present a single-cell transcriptome-wide view of the cynomolgus macaque placenta throughout gestation. Bioinformatics analyses and multiple validation experiments suggested that placental trophoblast cells exhibited stage-specific differences across gestation. Interactions between trophoblast cells and decidual cells also showed gestational stage-dependent differences. The trajectories of the villous core cells indicated that placental mesenchymal cells were derived from extraembryonic mesoderm (ExE.Meso) 1, whereas placental Hofbauer cells, erythrocytes, and endothelial cells were derived from ExE.Meso2. Comparative analyses of human and macaque placentas uncovered conserved features of placentation across species, and the discrepancies of extravillous trophoblast cells (EVTs) between human and macaque correlated to their differences in invasion patterns and maternal-fetal interactions. Our study provides a groundwork for elucidating the cellular basis of primate placentation.


Assuntos
Placenta , Transcriptoma , Animais , Gravidez , Feminino , Humanos , Transcriptoma/genética , Células Endoteliais , Placentação , Primatas , Macaca
14.
Trends Cell Biol ; 32(1): 18-29, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34417090

RESUMO

The basic body plan of the mammalian embryo is established through gastrulation, a pivotal early postimplantation event during which the three major germ layers (endoderm, ectoderm, and mesoderm) are specified with cellular and spatial diversity. Despite its basic and clinical importance, human embryo development from peri-implantation to gastrulation remains shrouded in mystery. Recent advances in the elongated in vitro culture of rodent and non-primate embryos and the construction of embryo-like structures have helped to improve understanding of the mechanisms of human early embryonic development. Here, we review the recent advances and possible future directions in the development of in vitro models to better understand human embryogenesis from peri-implantation to gastrulation.


Assuntos
Embrião de Mamíferos , Gastrulação , Animais , Desenvolvimento Embrionário , Humanos , Mamíferos
15.
Front Immunol ; 13: 1030222, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389736

RESUMO

The prognosis of human papillomavirus (HPV)-infected head and neck squamous cell carcinoma (HNSCC) is often better than that of HPV- cancer, which is possibly caused by the differences in their immune microenvironments. The contribution of macrophage, as a principal innate immune cell, to this phenomenon is still unclear. In this study, a single-cell atlas of 4,388 high-quality macrophages from 18 HPV- and 8 HPV+ HNSCC patients was constructed with single-cell RNA sequencing data. Eight macrophage subsets were identified from HNSCC, whereas their functional properties and developmental trajectory were delineated based on HPV status. Our results demonstrated that macrophages in HPV+ HNSCC exhibit stronger phagocytic ability, although the infiltration rate of macrophages decreased. From the results, a unique macrophage subset with TCR and CD3-specific signatures was identified from HPV-related HNSCC. These TCR+ macrophages potentially participate in the regulation of the TCR signaling pathway and phagocytosis. In conclusion, our results suggested that HPV could affect the infiltration rate, function, and differentiation of macrophages in HNSCC, whereas TCR+ macrophages play a critical role in the HNSCC microenvironment. These results provide new insights into the immune microenvironment of HNSCC and offer a valuable resource for the understanding of the immune landscape of HPV-related HNSCC, which will in turn help the development of immunotherapy strategies for the disease.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Infecções por Papillomavirus , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Neoplasias de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas/genética , Macrófagos , Análise de Sequência de RNA , Receptores de Antígenos de Linfócitos T/genética , Microambiente Tumoral
16.
Front Immunol ; 13: 880154, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35898491

RESUMO

Molecular assays on nasopharyngeal swabs act as a confirmatory test in coronavirus disease (COVID-19) diagnosis. However, the technical requirements of nasopharyngeal sampling and molecular assays limit the testing capabilities. Recent studies suggest the use of saliva for the COVID-19 diagnostic test. In this study, 44 patients diagnosed with COVID-19 in The Third People's Hospital of Shenzhen were enrolled. Saliva and serum specimens were obtained at different time points and the immunoglobulins against SARS-CoV-2 were measured. The results showed that saliva IgA presented a higher COI value than IgG and IgM. In matched saliva and serum samples, all saliva samples presented lower IgG levels than serum samples, and only one saliva sample presented a higher IgM level. The conversion rates of saliva IgA and the detection of viral nucleic acids were analyzed in the first and second weeks after hospitalization. The positive rates increased when combining saliva IgA and viral nucleic acid detection. In conclusion, our results provide evidence that saliva IgA could serve as a useful index for the early diagnosis of COVID-19.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , COVID-19/diagnóstico , Humanos , Imunoglobulina A , Imunoglobulina G , Imunoglobulina M , Saliva
17.
Adv Sci (Weinh) ; 9(28): e2202282, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35843885

RESUMO

The fundamental physical features such as the mechanical properties and microstructures of the uterus need to be considered when building in vitro culture platforms to mimic the uterus for embryo implantation and further development but have long been neglected. Here, a uterus-inspired niche (UN) constructed by grafting collagen gels onto polydimethylsiloxane based on a systematic investigation of a series of parameters (varying concentrations and thicknesses of collagen gel) is established to intrinsically specify and simulate the mechanics and microstructures of the mouse uterus. This brand-new and unique system is robust in supporting embryo invasion, as evidenced by the special interaction between the embryos and the UN system and successfully promoting E3.5 embryo development into the early organogenesis stage. This platform serves as a powerful tool for developmental biology and tissue engineering.


Assuntos
Blastocisto , Desenvolvimento Embrionário , Animais , Colágeno , Dimetilpolisiloxanos , Géis , Camundongos , Organogênese
18.
Adv Sci (Weinh) ; 7(17): 1903809, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32995116

RESUMO

Stem cells have emerged as a potential therapy for a range of neural insults, but their application in Alzheimer's disease (AD) is still limited and the mechanisms underlying the cognitive benefits of stem cells remain to be elucidated. Here, the effects of clinical-grade human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) on the recovery of cognitive ability in SAMP8 mice, a senescence-accelerated mouse model of AD is explored. A functional assay identifies that the core functional factor hepatocyte growth factor (HGF) secreted from hUC-MSCs plays critical roles in hUC-MSC-modulated recovery of damaged neural cells by down-regulating hyperphosphorylated tau, reversing spine loss, and promoting synaptic plasticity in an AD cell model. Mechanistically, structural and functional recovery, as well as cognitive enhancements elicited by exposure to hUC-MSCs, are at least partially mediated by HGF in the AD hippocampus through the activation of the cMet-AKT-GSK3ß signaling pathway. Taken together, these data strongly implicate HGF in mediating hUC-MSC-induced improvements in functional recovery in AD models.

19.
Science ; 366(6467)2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31672918

RESUMO

Gastrulation is a key event in embryonic development when the germ layers are specified and the basic animal body plan is established. The complexities of primate gastrulation remain a mystery because of the difficulties in accessing primate embryos at this stage. Here, we report the establishment of an in vitro culture (IVC) system that supports the continuous development of cynomolgus monkey blastocysts beyond early gastrulation up to 20 days after fertilization. The IVC embryos highly recapitulated the key events of in vivo early postimplantation development, including segregation of the epiblast and hypoblast, formation of the amniotic and yolk sac cavities, appearance of the primordial germ cells, and establishment of the anterior-posterior axis. Single-cell RNA-sequencing analyses of the IVC embryos provide information about lineage specification during primate early postimplantation development. This system provides a platform with which to explore the characteristics and mechanisms of early postimplantation embryogenesis in primates with possible conservation of cell movements and lineages in human embryogenesis.


Assuntos
Blastocisto/fisiologia , Técnicas de Cultura Embrionária , Implantação do Embrião/fisiologia , Gastrulação/fisiologia , Animais , Macaca fascicularis , Camundongos , RNA-Seq/métodos , Análise de Célula Única/métodos
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