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1.
Nature ; 580(7803): 376-380, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32296182

RESUMO

Mechanosensory feedback from the digestive tract to the brain is critical for limiting excessive food and water intake, but the underlying gut-brain communication pathways and mechanisms remain poorly understood1-12. Here we show that, in mice, neurons in the parabrachial nucleus that express the prodynorphin gene (hereafter, PBPdyn neurons) monitor the intake of both fluids and solids, using mechanosensory signals that arise from the upper digestive tract. Most individual PBPdyn neurons are activated by ingestion as well as the stimulation of the mouth and stomach, which indicates the representation of integrated sensory signals across distinct parts of the digestive tract. PBPdyn neurons are anatomically connected to the digestive periphery via cranial and spinal pathways; we show that, among these pathways, the vagus nerve conveys stomach-distension signals to PBPdyn neurons. Upon receipt of these signals, these neurons produce aversive and sustained appetite-suppressing signals, which discourages the initiation of feeding and drinking (fully recapitulating the symptoms of gastric distension) in part via signalling to the paraventricular hypothalamus. By contrast, inhibiting the same population of PBPdyn neurons induces overconsumption only if a drive for ingestion exists, which confirms that these neurons mediate negative feedback signalling. Our findings reveal a neural mechanism that underlies the mechanosensory monitoring of ingestion and negative feedback control of intake behaviours upon distension of the digestive tract.


Assuntos
Ingestão de Alimentos , Retroalimentação , Neurônios/fisiologia , Animais , Encefalinas/genética , Encefalinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Trato Gastrointestinal Superior/fisiologia
2.
Proc Natl Acad Sci U S A ; 120(21): e2217826120, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37192160

RESUMO

Molecular classification of gastric cancer (GC) identified a subgroup of patients showing chemoresistance and poor prognosis, termed SEM (Stem-like/Epithelial-to-mesenchymal transition/Mesenchymal) type in this study. Here, we show that SEM-type GC exhibits a distinct metabolic profile characterized by high glutaminase (GLS) levels. Unexpectedly, SEM-type GC cells are resistant to glutaminolysis inhibition. We show that under glutamine starvation, SEM-type GC cells up-regulate the 3 phosphoglycerate dehydrogenase (PHGDH)-mediated mitochondrial folate cycle pathway to produce NADPH as a reactive oxygen species scavenger for survival. This metabolic plasticity is associated with globally open chromatin structure in SEM-type GC cells, with ATF4/CEBPB identified as transcriptional drivers of the PHGDH-driven salvage pathway. Single-nucleus transcriptome analysis of patient-derived SEM-type GC organoids revealed intratumoral heterogeneity, with stemness-high subpopulations displaying high GLS expression, a resistance to GLS inhibition, and ATF4/CEBPB activation. Notably, coinhibition of GLS and PHGDH successfully eliminated stemness-high cancer cells. Together, these results provide insight into the metabolic plasticity of aggressive GC cells and suggest a treatment strategy for chemoresistant GC patients.


Assuntos
Fosfoglicerato Desidrogenase , Neoplasias Gástricas , Humanos , Fosfoglicerato Desidrogenase/genética , Fosfoglicerato Desidrogenase/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Linhagem Celular Tumoral , Glutamina/metabolismo , Nutrientes
3.
Langmuir ; 40(37): 19804-19815, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39239682

RESUMO

Here, we represent a solid-state route for the construction of MOF derived multifunctional Z-scheme NiCo2O4/NiO/C applied for the photocatalytic removal of methylene blue (dye) and tetracycline (drug) and the reduction of Cr(VI) (heavy metal). The developed solid-state method yielded a highly effective NiCo2O4/NiO/C catalyst by mechanically grinding independently produced Ni and Co-MOFs and subsequently pyrolyzing them. The use of different linkers in the Ni MOF (H3-BTC linker) and Co-MOF (2-methylimidazole linker) proved to be effective in constructing the NiCo2O4/NiO/C composite, ensuring a nonaggregated distribution on a carbon framework. Such a synthesized Z-scheme NiCo2O4/NiO/C composite has performed exceptionally well to achieve excellent degradation of MB (98.23% in 120 min) and TC (92.85% in 25 min) and Cr(VI) reduction (98.22% in 20 min), with excellent recyclability and stability. The NiCo2O4/NiO/C composite, synthesized using Ni and Co-MOFs prepared with different linkers, outperformed its counterpart prepared using Ni and Co-MOFs with identical linkers (either 2-methylimidazole or H3BTC). This study paves the way for the future synthesis of MOF derived bimetallic composites for photocatalytic applications.

4.
Child Care Health Dev ; 50(2): e13248, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38494984

RESUMO

BACKGROUND: Numerous participation measurement tools targeting children and youth have been developed. Despite the translation of these tools into specific languages and cultures, the reliability and validity of the translated versions remain uncertain. To address this gap in knowledge, this study aims to identify tools for assessing the participation of children aged 5-18 years and to appraise the psychometric properties of their translated versions. METHODS: Four electronic databases were searched for peer-reviewed studies published in English. Preferred Reporting Items for Systematic Reviews guidelines was followed. Study titles and abstracts were screened by four independent reviewers. Data were extracted for both original and translated versions of eligible tools. Instrument quality assessments were performed using the Outcome Measures Rating Form Guidelines. Any discrepancies were resolved by consensus. RESULTS: Out of the 31 measurement tools examined, 18 tools had at least one translated version available, and among those original measurement tools, a total of 58 translated versions were identified. The most widely translated tool was the Physical Activity Questionnaire for Children (12 languages), and the most frequently translated language was Chinese (7 tools). Most translated versions verified internal consistency and content validity. Only three translated versions were verified inter-rater reliability, and seven translated versions were tested criterion validity with the gold standard tools assessing participation of children (e.g., accelerometer, Pediatric Evaluation of Disability Inventory and four 24-h recalls). None of the translated versions were tested for intra-rater reliability and responsiveness. CONCLUSIONS: These findings can support the selection of psychometrically sound tools for children with disabilities, given their culture and language, and tool quality.


Assuntos
Qualidade de Vida , Traduções , Humanos , Criança , Adolescente , Inquéritos e Questionários , Reprodutibilidade dos Testes , Psicometria
5.
Semin Cancer Biol ; 83: 88-99, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-33753223

RESUMO

Methylation is a major post-translational modification (PTM) generated by methyltransferase on target proteins; it is recognized by the epigenetic reader to expand the functional diversity of proteins. Methylation can occur on specific lysine or arginine residues localized within regulatory domains in both histone and nonhistone proteins, thereby allowing distinguished properties of the targeted protein. Methylated residues are recognized by chromodomain, malignant brain tumor (MBT), Tudor, plant homeodomain (PHD), PWWP, WD-40, ADD, and ankyrin repeats by an induced-fit mechanism. Methylation-dependent activities regulate distinct aspects of target protein function and are largely reliant on methyl readers of histone and nonhistone proteins in various diseases. Methylation of nonhistone proteins that are recognized by methyl readers facilitates the degradation of unwanted proteins, as well as the stabilization of necessary proteins. Unlike nonhistone substrates, which are mainly monomethylated by methyltransferase, histones are di- or trimethylated by the same methyltransferases and then connected to other critical regulators by methyl readers. These fine-tuned controls by methyl readers are significant for the progression or inhibition of diseases, including cancers. Here, current knowledge and our perspectives about regulating protein function by methyl readers are summarized. We also propose that expanded research on the strong crosstalk mechanisms between methylation and other PTMs via methyl readers would augment therapeutic research in cancer.


Assuntos
Histonas , Neoplasias , Histonas/metabolismo , Humanos , Lisina/metabolismo , Metilação , Metiltransferases/metabolismo , Neoplasias/genética
6.
Diabetologia ; 66(3): 495-507, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36538063

RESUMO

AIMS/HYPOTHESIS: Type 2 diabetes is highly polygenic and influenced by multiple biological pathways. Rapid expansion in the number of type 2 diabetes loci can be leveraged to identify such pathways. METHODS: We developed a high-throughput pipeline to enable clustering of type 2 diabetes loci based on variant-trait associations. Our pipeline extracted summary statistics from genome-wide association studies (GWAS) for type 2 diabetes and related traits to generate a matrix of 323 variants × 64 trait associations and applied Bayesian non-negative matrix factorisation (bNMF) to identify genetic components of type 2 diabetes. Epigenomic enrichment analysis was performed in 28 cell types and single pancreatic cells. We generated cluster-specific polygenic scores and performed regression analysis in an independent cohort (N=25,419) to assess for clinical relevance. RESULTS: We identified ten clusters of genetic loci, recapturing the five from our prior analysis as well as novel clusters related to beta cell dysfunction, pronounced insulin secretion, and levels of alkaline phosphatase, lipoprotein A and sex hormone-binding globulin. Four clusters related to mechanisms of insulin deficiency, five to insulin resistance and one had an unclear mechanism. The clusters displayed tissue-specific epigenomic enrichment, notably with the two beta cell clusters differentially enriched in functional and stressed pancreatic beta cell states. Additionally, cluster-specific polygenic scores were differentially associated with patient clinical characteristics and outcomes. The pipeline was applied to coronary artery disease and chronic kidney disease, identifying multiple overlapping clusters with type 2 diabetes. CONCLUSIONS/INTERPRETATION: Our approach stratifies type 2 diabetes loci into physiologically interpretable genetic clusters associated with distinct tissues and clinical outcomes. The pipeline allows for efficient updating as additional GWAS become available and can be readily applied to other conditions, facilitating clinical translation of GWAS findings. Software to perform this clustering pipeline is freely available.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/genética , Estudo de Associação Genômica Ampla , Predisposição Genética para Doença/genética , Teorema de Bayes , Análise por Conglomerados , Polimorfismo de Nucleotídeo Único
7.
Cancer Sci ; 114(1): 187-200, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36114756

RESUMO

Retinoic acid receptor-related orphan receptor α (RORα) is a transcription factor involved in nuclear gene expression and a known tumor suppressor. RORα was the first identified substrate of lysine methylation-dependent degradation. However, the mechanisms of other post-translational modifications (PTMs) that occur in RORα remain largely unknown, especially in liver cancer. Arginine methylation is a common PTM in arginine residues of nonhistone and histone proteins and affects substrate protein function and fate. We found an analogous amino acid disposition containing R37 at the ROR N-terminus compared to histone H3 residue, which is arginine methylated. Here, we provide evidence that R37 methylation-dependent degradation is carried out by protein arginine methyltransferase 5 (PRMT5). Further, we discovered that PRMT5 regulated the interaction between the E3 ubiquitin ligase ITCH and RORα through RORα arginine methylation. Arginine methylation-dependent ubiquitination-mediated RORα degradation reduced downstream target gene activation. H2 O2 -induced reactive oxygen species (ROS) decreased PRMT5 protein levels, consequently increasing RORα protein levels in HepG2 liver cancer cells. In addition, ROS inhibited liver cancer progression by inducing apoptosis via PRMT5-mediated RORα methylation and the ITCH axis. Our results potentiate PRMT5 as an elimination target in cancer therapy, and this additional regulatory level within ROS signaling may help identify new targets for therapeutic intervention in liver cancer.


Assuntos
Arginina , Neoplasias Hepáticas , Humanos , Metilação , Espécies Reativas de Oxigênio/metabolismo , Arginina/metabolismo , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Histonas/metabolismo , Processamento de Proteína Pós-Traducional , Neoplasias Hepáticas/genética
8.
Opt Express ; 31(18): 29589-29595, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710755

RESUMO

We report a microlens array camera with variable apertures (MACVA) for high dynamic range (HDR) imaging by using microlens arrays with various sizes of apertures. The MACVA comprises variable apertures, microlens arrays, gap spacers, and a CMOS image sensor. The microlenses with variable apertures capture low dynamic range (LDR) images with different f-stops under single-shot exposure. The reconstructed HDR images clearly exhibit expanded dynamic ranges surpassing LDR images as well as high resolution without motion artifacts, comparable to the maximum MTF50 value observed among the LDR images. This compact camera provides, what we believe to be, a new perspective for various machine vision or mobile devices applications.

9.
J Cell Physiol ; 237(1): 13-28, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34237149

RESUMO

Autophagy is a highly conserved mechanism responsible for cellular homeostasis and integrity in a variety of physiological conditions. Materials targeted for degradation are directed to autophagosomes and autolysosomes, where they are broken down into their base components. Aberrant regulation of autophagy is significantly associated with various cancers and neurodegenerative diseases. Recently, accumulating evidence has revealed that the coordinated regulation of histone and non-histone protein modification is associated with autophagy. In this review, we highlight the recent progress that has been made in elucidating the molecular basis of protein methylation and acetylation associated with autophagy at the transcriptional and posttranslational levels. Furthermore, we discuss the importance of describing causality between protein methylation/acetylation and autophagy regulation as compelling therapeutic opportunities in cancer pathogenesis and progression.


Assuntos
Neoplasias , Processamento de Proteína Pós-Traducional , Acetilação , Autofagia/genética , Humanos , Metilação , Neoplasias/genética , Processamento de Proteína Pós-Traducional/genética
10.
Nature ; 534(7608): 553-7, 2016 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-27309807

RESUMO

Autophagy is a highly conserved self-digestion process, which is essential for maintaining homeostasis and viability in response to nutrient starvation. Although the components of autophagy in the cytoplasm have been well studied, the molecular basis for the transcriptional and epigenetic regulation of autophagy is poorly understood. Here we identify co-activator-associated arginine methyltransferase 1 (CARM1) as a crucial component of autophagy in mammals. Notably, CARM1 stability is regulated by the SKP2-containing SCF (SKP1-cullin1-F-box protein) E3 ubiquitin ligase in the nucleus, but not in the cytoplasm, under nutrient-rich conditions. Furthermore, we show that nutrient starvation results in AMP-activated protein kinase (AMPK)-dependent phosphorylation of FOXO3a in the nucleus, which in turn transcriptionally represses SKP2. This repression leads to increased levels of CARM1 protein and subsequent increases in histone H3 Arg17 dimethylation. Genome-wide analyses reveal that CARM1 exerts transcriptional co-activator function on autophagy-related and lysosomal genes through transcription factor EB (TFEB). Our findings demonstrate that CARM1-dependent histone arginine methylation is a crucial nuclear event in autophagy, and identify a new signalling axis of AMPK-SKP2-CARM1 in the regulation of autophagy induction after nutrient starvation.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Proteínas Quinases Associadas a Fase S/metabolismo , Transdução de Sinais , Transcrição Gênica , Animais , Arginina/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Linhagem Celular , Núcleo Celular/metabolismo , Privação de Alimentos , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/deficiência , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Histonas/metabolismo , Humanos , Lisossomos/genética , Metilação , Camundongos , Fosforilação , Proteínas Quinases Associadas a Fase S/antagonistas & inibidores , Proteínas Ligases SKP Culina F-Box/química , Proteínas Ligases SKP Culina F-Box/metabolismo
11.
Artigo em Inglês | MEDLINE | ID: mdl-36193564

RESUMO

A new functional composite was synthesized in this study comprising magnetic-cored dendrimer (MCD) modified with citric acid (CA), succinic acid (SA), and vanillic acid (VA) terminal groups. The CA-MCD, SA-MCD, and VA-MCD exhibited average particle size of 8-18 nm and superparamagnetic behavior. Adsorption potential of the composite was assessed by monitoring methylene blue (MB) removal from contaminated water. The CA-MCD attained adsorption equilibrium in 30 min while SA-MCD and VA-MCD achieved equilibrium in 60 min. The Langmuir model better fitted the adsorption results than the Freundlich model, indicating a monolayer mode of MB adsorption on the composite. Maximum adsorption capacity of CA-MCD, SA-MCD, and VA-MCD was 216.30 mg/g, 184.29 mg/g, and 196.58 mg/g, respectively. The CA-MCD exhibited best adsorption performance by removing 99% MB at pH = 11. In reusability experiments, the CA-MCD, SA-MCD, and VA-MCD maintained over 90% MB adsorption for both 15 mg/L and 50 mg/L solutions in the third cycle. Overall, the organic acid-functionalized MCDs with high adsorption capacity and reusability potential showed utility for practical application for wastewater decontamination.


Assuntos
Dendrímeros , Poluentes Químicos da Água , Azul de Metileno/química , Adsorção , Águas Residuárias/química , Ácido Vanílico , Ácido Succínico , Poluentes Químicos da Água/química , Ácido Cítrico/química , Água , Fenômenos Magnéticos , Cinética , Concentração de Íons de Hidrogênio
12.
Opt Express ; 29(2): 1333-1339, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33726351

RESUMO

We report an ultrathin arrayed camera (UAC) for high-contrast near infrared (NIR) imaging by using microlens arrays with a multilayered light absorber. The UAC consists of a multilayered composite light absorber, inverted microlenses, gap-alumina spacers and a planar CMOS image sensor. The multilayered light absorber was fabricated through lift-off and repeated photolithography processes. The experimental results demonstrate that the image contrast is increased by 4.48 times and the MTF 50 is increased by 2.03 times by eliminating optical noise between microlenses through the light absorber. The NIR imaging of UAC successfully allows distinguishing the security strip of authentic bill and the blood vessel of finger. The ultrathin camera offers a new route for diverse applications in biometric, surveillance, and biomedical imaging.


Assuntos
Fotografação/instrumentação , Espectroscopia de Luz Próxima ao Infravermelho/instrumentação , Desenho de Equipamento , Lentes
13.
FASEB J ; 34(8): 10228-10241, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32543734

RESUMO

Peroxidasin (PXDN) has been reported to crosslink the C-terminal non-collagenous domains of collagen IV (Col IV) by forming covalent sulfilimine bond. Here, we explored the physiological role of PXDN and its mechanism of action in endothelial cell survival and growth. Silencing of PXDN using siRNAs decreased cell proliferation without increase of the number of detached cells and decreased cell viability under serum-starved condition with increased fragmented nuclei and caspase 3/7 activity. Conditioned medium (CM) containing wild-type PXDN restored the proliferation of PXDN-depleted cells, but CM containing mutant PXDN with deletion of either N-terminal extracellular matrix (ECM) motifs or peroxidase domain failed to restore PXDN function. Accordingly, anti-PXDN antibody [raised against IgC2 (3-4) subdomain within ECM motifs] and peroxidase inhibitor phloroglucinol prevented the rescue of the PXDN-depleted cells by PXDN-containing CM. PXDN depletion resulted in loss of sulfilimine crosslinks, and decreased dense fibrillar network assembly of not only Col IV, but also fibronectin and laminin like in Col IV knockdown. Exogenous PXDN-containing CM restored ECM assembly as well as proliferation of PXDN-depleted cells. Accordingly, purified recombinant PXDN protein restored the proliferation and ECM assembly, and prevented cell death of the PXDN-depleted cells. PXDN depletion also showed reduced growth factors-induced phosphorylation of FAK and ERK1/2. In addition, siPXDN-transfected cell-derived matrix failed to provide full ECM-mediated activation of FAK and ERK1/2. These results indicate that both the ECM motifs and peroxidase activity are essential for the cellular function of PXDN and that PXDN is crucial for ECM assembly for survival and growth signaling.


Assuntos
Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Proteínas da Matriz Extracelular/metabolismo , Matriz Extracelular/metabolismo , Iminas/farmacologia , Peroxidase/metabolismo , Transdução de Sinais/efeitos dos fármacos , Membrana Basal/efeitos dos fármacos , Membrana Basal/metabolismo , Morte Celular/efeitos dos fármacos , Células Cultivadas , Colágeno Tipo IV/metabolismo , Células Endoteliais/metabolismo , Fibronectinas/metabolismo , Quinase 1 de Adesão Focal/metabolismo , Células HEK293 , Células Endoteliais da Veia Umbilical Humana , Humanos , Laminina/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Peroxidases/metabolismo , Peroxidasina
14.
J Epidemiol ; 31(12): 593-600, 2021 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-32863371

RESUMO

BACKGROUND: The incidence and prevalence of endometriosis remain unclear due to diagnostic difficulties. Especially, there has been little information regarding the population-based epidemiology of endometriosis. The purpose of this study is to estimate the prevalence and incidence of endometriosis in Korea based on the health insurance claims data. METHODS: This study is a retrospective cohort study using the Korean National Health Insurance Service-National Sample Cohort, which correspond to approximately 1 million Korean populations from 2002 to 2013. Patients aged 15-54 years were selected, and the prevalence and incidence of endometriosis were estimated by time and age groups. RESULTS: The age-adjusted prevalence rate of endometriosis also increased from 2.12 per 1,000 persons (95% confidence interval [CI], 2.01-2.24) in 2002 to 3.56 per 1,000 persons (95% CI, 3.40-3.71) in 2013. The average adjusted incidence showed no statistically significant increase. However, the age-specific incidence of the 15-19 and 20-24 years age groups increased significantly from 0.24 and 1.29 per 1,000 persons in 2003 to 2.73 and 2.71 per 1,000 persons in 2013 (R2 = 0.93 and 0.77, P < 0.001), while the incidence rate of the age group 40-44 and 45-49 years decreased from 2.36 and 1.72 per 1,000 persons in 2003 to 0.81 and 0.27 per 1,000 persons in 2013 (R2 = 0.83 and 0.89, P < 0.001). CONCLUSION: The prevalence and incidence of endometriosis in Korean women were lower than that of previous reports in high-risk population studies. Furthermore, we found a significant increase in the diagnosis of endometriosis in younger age groups.


Assuntos
Endometriose , Estudos de Coortes , Endometriose/epidemiologia , Feminino , Humanos , Incidência , Programas Nacionais de Saúde , Prevalência , República da Coreia/epidemiologia , Estudos Retrospectivos
15.
Proc Natl Acad Sci U S A ; 115(46): 11766-11771, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-30377265

RESUMO

Janus tyrosine kinase 2 (JAK2)-signal transducer and activator of transcription 3 (STAT3) signaling pathway is essential for modulating cellular development, differentiation, and homeostasis. Thus, dysregulation of JAK2-STAT3 signaling pathway is frequently associated with human malignancies. Here, we provide evidence that lysine-specific demethylase 3A (KDM3A) functions as an essential epigenetic enzyme for the activation of JAK2-STAT3 signaling pathway. KDM3A is tyrosine-phosphorylated by JAK2 in the nucleus and functions as a STAT3-dependent transcriptional coactivator. JAK2-KDM3A signaling cascade induced by IL-6 leads to alteration of histone H3K9 methylation as a predominant epigenetic event, thereby providing the functional and mechanistic link between activation of JAK2-STAT3 signaling pathway and its epigenetic control. Together, our findings demonstrate that inhibition of KDM3A phosphorylation could be a potent therapeutic strategy to control oncogenic effect of JAK2-STAT3 signaling pathway.


Assuntos
Histona Desmetilases com o Domínio Jumonji/metabolismo , Epigênese Genética , Células HEK293/metabolismo , Células HeLa , Histonas/metabolismo , Humanos , Interleucina-6/metabolismo , Janus Quinase 2/metabolismo , Histona Desmetilases com o Domínio Jumonji/genética , Fosforilação , Proteínas Tirosina Quinases/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Ativação Transcricional
16.
Biochem Biophys Res Commun ; 526(1): 176-183, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32201075

RESUMO

Autophagy is an essential process to maintain cell survival and homeostasis under various stress conditions. Here, we report that lysine-specific demethylase 3A (KDM3A) plays an important role in starvation-induced autophagy. Using Kdm3a knockout mice, we demonstrate that KDM3A is crucial for proper hepatic autophagy in vivo. Hepatic mRNA expression analysis and ChIP assay in WT and Kdm3a knockout mouse livers reveal that KDM3A activates autophagy genes by reducing histone H3K9me2 levels upon fasting. Together, our finding represents previously unidentified function of KDM3A as a key regulator of autophagy, implicating potential therapeutic approaches for autophagy-related diseases.


Assuntos
Autofagia , Histona Desmetilases com o Domínio Jumonji/metabolismo , Animais , Autofagossomos/metabolismo , Jejum , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Células Hep G2 , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Fígado/citologia , Fígado/metabolismo , Lisossomos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
17.
J Transl Med ; 18(1): 236, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532292

RESUMO

BACKGROUND: The in vitro production of mature human red blood cells (RBCs) from induced pluripotent stem cells (iPSCs) has been the focus of research to meet the high demand for blood transfusions. However, limitations like high costs and technological requirements restrict the use of RBCs produced by iPSC differentiation to specific circumstances, such as for patients with rare blood types or alloimmunized patients. In this study, we developed a detailed protocol for the generation of iPSC lines derived from peripheral blood of donors with O D-positive blood and rare blood types (D-and Jr(a-)) and subsequent erythroid differentiation. METHODS: Mononuclear cells separated from the peripheral blood of O D-positive and rare blood type donors were cultured to produce and expand erythroid progenitors and reprogrammed into iPSCs. A 31-day serum-free, xeno-free erythroid differentiation protocol was used to generate reticulocytes. The stability of iPSC lines was confirmed with chromosomal analysis and RT-PCR. Morphology and cell counts were determined by microscopy observations and flow cytometry. RESULTS: Cells from all donors were successfully used to generate iPSC lines, which were differentiated into erythroid precursors without any apparent chromosomal mutations. This differentiation protocol resulted in moderate erythrocyte yield per iPSC. CONCLUSIONS: It has previously only been hypothesized that erythroid differentiation from iPSCs could be used to produce RBCs for transfusion to patients with rare blood types or who have been alloimmunized. Our results demonstrate the feasibility of producing autologous iPSC-differentiated RBCs for clinical transfusions in patients without alternative options.


Assuntos
Células-Tronco Pluripotentes Induzidas , Diferenciação Celular , Eritrócitos , Humanos
18.
Stem Cells ; 37(1): 77-88, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30281870

RESUMO

Mesenchymal stromal/stem cells (MSCs) have been developed as a promising source for cell-based therapies of ischemic disease. However, there are some hurdles in their clinical application such as poor cell engraftment and inconsistent stem cell potency. In this study, we sought to find biomarkers for predicting potency of MSCs for proangiogenic therapy to improve their beneficial effects. Large variations were observed in proangiogenic factor secretion profiles of conditioned media derived from nine different donor-derived Wharton's jelly (WJ)-derived MSCs and 8 factors among 55 angiogenesis-related factors were secreted at considerable levels. Two distinct WJ-MSCs that had the lowest or the highest secretion of these eight factors showed corresponding proangiogenic activities in in vitro angiogenesis assays. When four additional different donor-derived WJ-MSCs were further examined, proangiogenic activities in migration and tube formation of endothelial cells and in in vivo Matrigel plug assay were highly consistent with secretion levels of four major factors (angiogenin, interleukin-8, monocyte chemoattractant protein-1, and vascular endothelial growth factor). Such correlation was also observed in vascular regenerative effect in a mouse hind limb ischemia model. Blocking of these four factors by neutralizing antibodies or knockdown of them by siRNA treatment resulted in significant inhibition of proangiogenic activities of not only WJ-MSCs, but also bone marrow-derived MSCs. These results suggest that these four factors may represent efficient biomarkers for predicting vascular regenerative efficacy of MSCs. Stem Cells 2019;37:77-88.


Assuntos
Células-Tronco Mesenquimais/metabolismo , Neovascularização Fisiológica/genética , Comunicação Parácrina/genética , Animais , Diferenciação Celular , Humanos , Masculino , Camundongos
19.
Mol Cell ; 48(4): 572-86, 2012 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-23063525

RESUMO

Ubiquitination plays a major role in protein degradation. Although phosphorylation-dependent ubiquitination is well known for the regulation of protein stability, methylation-dependent ubiquitination machinery has not been characterized. Here, we provide evidence that methylation-dependent ubiquitination is carried out by damage-specific DNA binding protein 1 (DDB1)/cullin4 (CUL4) E3 ubiquitin ligase complex and a DDB1-CUL4-associated factor 1 (DCAF1) adaptor, which recognizes monomethylated substrates. Molecular modeling and binding affinity studies reveal that the putative chromo domain of DCAF1 directly recognizes monomethylated substrates, whereas critical binding pocket mutations of the DCAF1 chromo domain ablated the binding from the monomethylated substrates. Further, we discovered that enhancer of zeste homolog 2 (EZH2) methyltransferase has distinct substrate specificities for histone H3K27 and nonhistones exemplified by an orphan nuclear receptor, RORα. We propose that EZH2-DCAF1/DDB1/CUL4 represents a previously unrecognized methylation-dependent ubiquitination machinery specifically recognizing "methyl degron"; through this, nonhistone protein stability can be dynamically regulated in a methylation-dependent manner.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas Culina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Complexo Repressor Polycomb 2/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste , Humanos , Células MCF-7 , Metilação , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Proteínas Serina-Treonina Quinases , Especificidade por Substrato
20.
BMC Health Serv Res ; 20(1): 166, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32131818

RESUMO

BACKGROUND: The look-back period is needed to define baseline population for estimating incidence. However, short look-back period is known to overestimate incidence of diseases misclassifying prevalent cases to incident cases. The purpose of this study is to evaluate the impact of the various length of look-back period on the observed incidences of uterine leiomyoma, endometriosis and adenomyosis, and to estimate true incidences considering the misclassification errors in the longitudinal administrative data in Korea. METHODS: A total of 319,608 women between 15 to 54 years of age in 2002 were selected from Korea National Health Insurance Services (KNHIS) cohort database. In order to minimize misclassification bias incurred when applying various length of look-back period, we used 11 years of claim data to estimate the incidence by equally setting the look-back period to 11 years for each year using prediction model. The association between the year of diagnosis and the number of prevalent cases with the misclassification rates by each look-back period was investigated. Based on the findings, prediction models on the proportion of misclassified incident cases were developed using multiple linear regression. RESULTS: The proportion of misclassified incident cases of uterine leiomyoma, endometriosis and adenomyosis were 32.8, 10.4 and 13.6% respectively for the one-year look-back period in 2003. These numbers decreased to 6.3% in uterine leiomyoma and - 0.8% in both endometriosis and adenomyosis using all available look-back periods (11 years) in 2013. CONCLUSION: This study demonstrates approaches for estimating incidences considering the different proportion of misclassified cases for various length of look-back period. Although the prediction model used for estimation showed strong R-squared values, follow-up studies are required for validation of the study results.


Assuntos
Endometriose/epidemiologia , Leiomioma/epidemiologia , Adolescente , Adulto , Estudos de Coortes , Bases de Dados Factuais , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Adulto Jovem
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