RESUMO
During microRNA (miRNA) biogenesis, two endonucleolytic reactions convert stem-loop-structured precursors into mature miRNAs. These processing steps can be posttranscriptionally regulated by RNA-binding proteins (RBPs). Here, we have used a proteomics-based pull-down approach to map and characterize the interactome of a multitude of pre-miRNAs. We identify â¼180 RBPs that interact specifically with distinct pre-miRNAs. For functional validation, we combined RNAi and CRISPR/Cas-mediated knockout experiments to analyze RBP-dependent changes in miRNA levels. Indeed, a large number of the investigated candidates, including splicing factors and other mRNA processing proteins, have effects on miRNA processing. As an example, we show that TRIM71/LIN41 is a potent regulator of miR-29a processing and its inactivation directly affects miR-29a targets. We provide an extended database of RBPs that interact with pre-miRNAs in extracts of different cell types, highlighting a widespread layer of co- and posttranscriptional regulation of miRNA biogenesis.
Assuntos
MicroRNAs/biossíntese , Precursores de RNA/biossíntese , Processamento Pós-Transcricional do RNA , Proteínas de Ligação a RNA/metabolismo , Transcrição Gênica , Células A549 , Sítios de Ligação , Sistemas CRISPR-Cas , RNA Helicases DEAD-box/metabolismo , Bases de Dados Genéticas , Regulação da Expressão Gênica , Genômica/métodos , Células HEK293 , Células HeLa , Células Hep G2 , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Células Jurkat , Células MCF-7 , MicroRNAs/química , MicroRNAs/genética , Conformação de Ácido Nucleico , Ligação Proteica , Proteômica/métodos , Interferência de RNA , Precursores de RNA/química , Precursores de RNA/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Ribonuclease III/metabolismo , Análise de Sequência de RNA , Relação Estrutura-Atividade , Transfecção , Proteínas com Motivo Tripartido/genética , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismoRESUMO
BACKGROUND: On March 16th 2024, the first case of Human infection with avian influenza H10N3 since the end of the global COVID-19 Pandemic was reported in Kunming, China. To enhance comprehension of the source of infection and risk factors of the H10N3 virus infection, this case report summarizes the clinical features, epidemiological investigation, and laboratory test results. Provides recommendations for the prevention and control of Human infection with avian influenza H10N3. CASE PRESENTATION: A 51-year-old male with a history of COVID-19 infection and a smoking habit of 30 years, worked in livestock breeding and was exposed to sick and dead poultry before falling ill with fever and chills on 28th February 2024. A week later, he was diagnosed with severe pneumonia, influenza, and respiratory failure by the Third People's Hospital of Kunming(KM-TPH). He was discharged on 17th April and none of his 6 close contacts showed any symptoms of illness. Environmental samples taken from the epidemic spot revealed that peacock feces tested positive for avian influenza sub-type H9 and waterfowl specimens showed positive results for avian influenza sub-type H5. Gene sequencing conducted on positive specimens from the patient's respiratory tract by the Chinese Centre for Disease Control and Prevention (CCDC) showed a high degree of similarity (98.6-99.5%) with the strain responsible for the second global case of human infected with H10N3 (reported from Zhejiang, China 2022). CONCLUSIONS: According to the available epidemiological information, there is limited evidence to suggest that H10N3 viruses are excessively lethal. However, adaptive site mutations have been observed in the H10N3 isoform of mammals. While it is unlikely that the H10N3 virus will spread among humans, the possibility of additional cases cannot be entirely ruled out. Symptoms of human infection with H10N3 avian influenza are similar to those of common respiratory infections, which may result in them being overlooked during initial clinical consultations. Therefore, it is essential to improve surveillance of the H10 sub-type of avian influenza and to increase the awareness of hospital-related workers of cases of pneumonia of unknown origin.
Assuntos
COVID-19 , Influenza Aviária , Influenza Humana , Humanos , Masculino , Pessoa de Meia-Idade , Influenza Humana/virologia , Animais , Influenza Aviária/virologia , COVID-19/epidemiologia , China/epidemiologia , Aves Domésticas/virologia , Vírus da Influenza A/genética , Vírus da Influenza A/isolamento & purificação , SARS-CoV-2/genética , FilogeniaRESUMO
BACKGROUND: Arnica montana and Bellis perennis are two medicinal plants that are thought to accelerate bone repair in homoeopathic literature. Mesenchymal stem cells (MSCs) are multipotent stem cells with the ability to differentiate and regenerate bone or osteogenesis. Hence, we aimed to determine the role of Arnica montana and Bellis perennis on the osteogenic differentiation of the C3H10T1/2 stem cell line. METHODS AND RESULTS: The cell proliferation of Arnica montana and Bellis perennis was evaluated by MTT assay. Osteogenic differentiation of C3H10T1/2 was induced by the addition of ß-glycerophosphate, ascorbic acid and dexamethasone in the differentiation medium over 3 weeks. Cells were treated with Arnica montana and Bellis perennis individually as well as in combination. The osteogenic differentiation potential of Arnica montana and Bellis perennis to differentiate C3H10T1/2 into osteoblasts was measured by alkaline phosphatase activity, alizarin red staining and the expression of Osteocalcin using immunostaining and qRT-PCR. Arnica montana and Bellis perennis could enhance C3H10T1/2 cell proliferation at 1600 µg. Further, the compound showed the ability to augment osteogenesis as confirmed by increased expression of alkaline phosphatase and enhanced calcium accumulation as seen by the Alizarin Red staining and quantification. Enhanced osteogenesis was further supported by the increased expression of osteocalcin in the treated cells with individual and combined doses of Arnica montana and Bellis perennis. Therefore, the findings provide additional support for the positive impact of Arnica montana and Bellis perennis on bone formation. CONCLUSIONS: Our findings suggest that homoeopathic compounds Arnica montana and Bellis perennis can augment osteogenesis individually as well as in combination.
Assuntos
Arnica , Diferenciação Celular , Proliferação de Células , Células-Tronco Mesenquimais , Osteogênese , Extratos Vegetais , Osteogênese/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Diferenciação Celular/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Camundongos , Extratos Vegetais/farmacologia , Linhagem Celular , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoblastos/citologia , Fosfatase Alcalina/metabolismo , Células-Tronco Multipotentes/efeitos dos fármacos , Células-Tronco Multipotentes/citologia , Células-Tronco Multipotentes/metabolismo , Osteocalcina/metabolismo , Osteocalcina/genéticaRESUMO
BACKGROUND: C3H10T1/2 is a mesenchymal cell line capable of differentiating into osteoblasts, adipocytes and chondrocytes. The differentiation of these cells into osteoblasts is modulated by various transcription factors, such as RUNX2. Additionally, several interconnected signaling pathways, including the NOTCH pathway, play a crucial role in modulating their differentiation into mature bone cells. We have investigated the roles of DLK1 and DLK2, two non-canonical inhibitory ligands of NOTCH receptors, in the osteogenic differentiation of C3H10T1/2 cells. RESULTS: Our results corroborate existing evidence that DLK1 acts as an inhibitor of osteogenesis. In contrast, we demonstrate for the first time that DLK2 enhances this differentiation process. Additionally, our data suggest that NOTCH2, 3 and 4 receptors may promote osteogenesis, as indicated by their increased expression during this process, whereas NOTCH1 expression, which decreases during cell differentiation, might inhibit osteogenesis. Moreover, treatment with DAPT, a NOTCH signaling inhibitor, impeded osteogenic differentiation. We have confirmed the increase in ERK1/2 MAPK and p38 MAPK phosphorylation in C3H10T1/2 cells induced to differentiate to osteoblasts. Our new findings reveal increased ERK1/2 MAPK phosphorylation in differentiated C3H10T1/2 cells with a decrease in DLK1 expression or an overexpression of DLK2, which is coincident with the behavior of those transfectants where we have detected an increase in osteogenic differentiation. Additionally, p38 MAPK phosphorylation increases in differentiated C3H10T1/2 cells with reduced DLK1 levels. CONCLUSIONS: Our results suggest that DLK1 may inhibit osteogenesis, while DLK2 may promote it, by modulating NOTCH signaling and the phosphorylation of ERK1/2 and p38 MAPK pathways. Given the established inhibitory effect of DLK proteins on NOTCH signaling, these new insights could pave the way for developing future therapeutic strategies aimed at treating bone diseases.
Assuntos
Proteínas de Ligação ao Cálcio , Diferenciação Celular , Peptídeos e Proteínas de Sinalização Intercelular , Células-Tronco Mesenquimais , Osteogênese , Receptores Notch , Diferenciação Celular/fisiologia , Osteogênese/fisiologia , Animais , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Camundongos , Receptores Notch/metabolismo , Células-Tronco Mesenquimais/metabolismo , Transdução de Sinais/fisiologia , Linhagem Celular , Osteoblastos/metabolismoRESUMO
Tetrabromobisphenol A (TBBPA), a widely-used brominated flame retardant, has been revealed to exert endocrine disrupting effects and induce adipogenesis. Given the high structural similarities of TBBPA analogues and their increasing exposure risks, their effects on lipid metabolism are necessary to be explored. Herein, 9 representative TBBPA analogues were screened for their interference on 3T3-L1 preadipocyte adipogenesis, differentiation of C3H10T1/2 mesenchymal stem cells (MSCs) to brown adipocytes, and lipid accumulation of HepG2 cells. TBBPA bis(2-hydroxyethyl ether) (TBBPA-BHEE), TBBPA mono(2-hydroxyethyl ether) (TBBPA-MHEE), TBBPA bis(glycidyl ether) (TBBPA-BGE), and TBBPA mono(glycidyl ether) (TBBPA-MGE) were found to induce adipogenesis in 3T3-L1 preadipocytes to different extends, as evidenced by the upregulated intracellular lipid generation and expressions of adipogenesis-related biomarkers. TBBPA-BHEE exhibited a stronger obesogenic effect than did TBBPA. In contrast, the test chemicals had a weak impact on the differentiation process of C3H10T1/2 MSCs to brown adipocytes. As for hepatic lipid formation test, only TBBPA mono(allyl ether) (TBBPA-MAE) was found to significantly promote triglyceride (TG) accumulation in HepG2 cells, and the effective exposure concentration of the chemical under oleic acid (OA) co-exposure was lower than that without OA co-exposure. Collectively, TBBPA analogues may perturb lipid metabolism in multiple tissues, which varies with the test tissues. The findings highlight the potential health risks of this kind of emerging chemicals in inducing obesity, non-alcoholic fatty liver disease (NAFLD) and other lipid metabolism disorders, especially under the conditions in conjunction with high-fat diets.
Assuntos
Células 3T3-L1 , Adipogenia , Retardadores de Chama , Metabolismo dos Lipídeos , Bifenil Polibromatos , Bifenil Polibromatos/toxicidade , Metabolismo dos Lipídeos/efeitos dos fármacos , Animais , Camundongos , Adipogenia/efeitos dos fármacos , Humanos , Retardadores de Chama/toxicidade , Células Hep G2 , Diferenciação Celular/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismoRESUMO
The widespread use of wearable devices has enabled continuous monitoring of biometric data, including heart rate variability (HRV) and resting heart rate (RHR). However, the validity of these measurements, particularly from consumer devices like Apple Watch, remains underexplored. This study aimed to validate HRV measurements obtained from Apple Watch Series 9 and Ultra 2 against the Polar H10 chest strap paired with the Kubios HRV software, which together served as the reference standard. A prospective cohort of 39 healthy adults provided 316 HRV measurements over a 14-day period. Generalized Estimating Equations were used to assess the difference in HRV between devices, accounting for repeated measures. Apple Watch tended to underestimate HRV by an average of 8.31 ms compared to the Polar H10 (p = 0.025), with a mean absolute percentage error (MAPE) of 28.88% and a mean absolute error (MAE) of 20.46 ms. The study found no significant impact of RHR discrepancies on HRV differences (p = 0.156), with RHR showing a mean difference of -0.08 bpm, an MAPE of 5.91%, and an MAE of 3.73 bpm. Equivalence testing indicated that the HRV measurements from Apple Watch did not fall within the pre-specified equivalence margin of ±10 ms. Despite accurate RHR measurements, these findings underscore the need for improved HRV algorithms in consumer wearables and caution in interpreting HRV data for clinical or performance monitoring.
Assuntos
Frequência Cardíaca , Dispositivos Eletrônicos Vestíveis , Humanos , Frequência Cardíaca/fisiologia , Masculino , Feminino , Adulto , Estudos Prospectivos , Monitorização Fisiológica/métodos , Pessoa de Meia-Idade , Adulto Jovem , Software , Descanso/fisiologiaRESUMO
Aberrant activation of hedgehog (Hh) signaling has been implicated in various cancers. Current FDA-approved inhibitors target the seven-transmembrane receptor Smoothened, but resistance to these drugs has been observed. It has been proposed that a more promising strategy to target this pathway is at the GLI1 transcription factor level. GANT61 was the first small molecule identified to directly suppress GLI-mediated activity; however, its development as a potential anti-cancer agent has been hindered by its modest activity and aqueous chemical instability. Our study aimed to identify novel GLI1 inhibitors. JChem searches identified fifty-two compounds similar to GANT61 and its active metabolite, GANT61-D. We combined high-throughput cell-based assays and molecular docking to evaluate these analogs. Five of the fifty-two GANT61 analogs inhibited activity in Hh-responsive C3H10T1/2 and Gli-reporter NIH3T3 cellular assays without cytotoxicity. Two of the GANT61 analogs, BAS 07019774 and Z27610715, reduced Gli1 mRNA expression in C3H10T1/2 cells. Treatment with BAS 07019774 significantly reduced cell viability in Hh-dependent glioblastoma and lung cancer cell lines. Molecular docking indicated that BAS 07019774 is predicted to bind to the ZF4 region of GLI1, potentially interfering with its ability to bind DNA. Our findings show promise in developing more effective and potent GLI inhibitors.
Assuntos
Proteínas Hedgehog , Simulação de Acoplamento Molecular , Piridinas , Pirimidinas , Proteína GLI1 em Dedos de Zinco , Piridinas/farmacologia , Piridinas/química , Proteína GLI1 em Dedos de Zinco/metabolismo , Proteína GLI1 em Dedos de Zinco/genética , Pirimidinas/farmacologia , Pirimidinas/química , Proteínas Hedgehog/metabolismo , Humanos , Animais , Camundongos , Linhagem Celular Tumoral , Células NIH 3T3 , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Transdução de Sinais/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacosRESUMO
The bone morphogenetic protein (BMP) signaling pathway plays pivotal roles in various biological processes during embryogenesis and adult homeostasis. Transmembrane anterior posterior transformation 1 (TAPT1) is an evolutionarily conserved protein involved in murine axial skeletal patterning. Genetic defects in TAPT1 result in complex lethal osteochondrodysplasia. However, the specific cellular activity of TAPT1 is not clear. Herein, we report that TAPT1 inhibits BMP signaling and destabilizes the SMAD1/5 protein by facilitating its interaction with SMURF1 E3 ubiquitin ligase, which leads to SMAD1/5 proteasomal degradation. In addition, we found that the activation of BMP signaling facilitates the redistribution of TAPT1 and promotes its association with SMAD1. TAPT1-deficient murine C2C12 myoblasts or C3H/10T1/2 mesenchymal stem cells exhibit elevated SMAD1/5/9 protein levels, which amplifies BMP activation, in turn leading to a boost in the transdifferentiation or differentiation processing of these distinct TAPT1-deficient cell lines changing into mature osteoblasts. Furthermore, the enhancing effect of TAPT1 deficiency on osteogenic differentiation of C3H/10T1/2 cells was observed in an in vivo ectopic bone formation model. Importantly, a subset of TAPT1 mutations identified in humans with lethal skeletal dysplasia exhibited gain-of-function activity on SMAD1 protein levels. Thus, this finding elucidates the role of TAPT1 in the regulation of SMAD1/5 protein stability for controlling BMP signaling.
Assuntos
Transdução de Sinais , Proteína Smad1 , Proteína Smad5 , Animais , Humanos , Camundongos , Proteína Morfogenética Óssea 2/metabolismo , Diferenciação Celular , Linhagem Celular , Proteínas de Membrana , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteogênese/genética , Estabilidade Proteica , Transdução de Sinais/genética , Proteína Smad1/genética , Proteína Smad1/metabolismo , Proteína Smad5/genética , Proteína Smad5/metabolismo , Proteína Smad8/genética , Proteína Smad8/metabolismoRESUMO
The H10 subtypes of avian influenza viruses pose a continual threat to the poultry industry and human health. The sporadic spillover of H10 subtypes viruses from poultry to humans is represented by the H10N8 human cases in 2013 and the recent H10N3 human infection in 2021. However, the genesis and characteristics of the recent reassortment H10N3 viruses have not been systemically investigated. In this study, we characterized 20 H10N3 viruses isolated in live poultry markets during routine nationwide surveillance in China from 2014 to 2021. The viruses in the recent reassortant genotype acquired their hemagglutinin (HA) and neuraminidase (NA) genes from the duck H10 viruses and H7N3 viruses, respectively, whereas the internal genes were derived from chicken H9N2 viruses as early as 2019. Receptor-binding analysis indicated that two of the tested H10N3 viruses had a higher affinity for human-type receptors than for avian-type receptors, highlighting the potential risk of avian-to-human transmission. Animal studies showed that only viruses belonging to the recent reassortant genotype were pathogenic in mice; two tested viruses transmitted via direct contact and one virus transmitted by respiratory droplets in guinea pigs, though with limited efficiency. These findings emphasize the need for enhanced surveillance of H10N3 viruses.
Assuntos
Vírus da Influenza A Subtipo H9N2 , Influenza Aviária , Influenza Humana , Humanos , Animais , Cobaias , Camundongos , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H7N3 , Aves Domésticas , Galinhas , China/epidemiologia , Filogenia , Vírus Reordenados/genéticaRESUMO
3-tert-Butyl-4-hydroxyanisole (3-BHA), one of the most commonly used antioxidants in foodstuffs, has been identified as an environmental endocrine disruptor (EED) with obesogenic activity. Given the increasing concern on EED-caused dysfunction in lipid metabolism, whether 3-BHA could influence the development of brown adipocytes is worthy of being explored. In this study, the effect of 3-BHA on the differentiation of C3H10T1/2 mesenchymal stem cells (MSCs) into brown adipocytes was investigated. Exposure to 3-BHA promoted lipogenesis of the differentiated cells, as evidenced by the increased intracellular lipid accumulation and elevated expressions of adipogenic biomarkers, including peroxisome proliferator-activated receptor γ (PPARγ), Perilipin, Adiponectin, and fatty acid binding protein 4 (FABP4). Surprisingly, the thermogenic capacity of the differentiated cells was compromised as a result of 3-BHA exposure, because neither intracellular mitochondrial contents nor expressions of thermogenic biomarkers, including uncoupling protein 1 (UCP1), peroxisome proliferator-activated receptor γ coactivator 1α (PGC1α), cell-death-inducing DNA fragmentation factor α subunit-like effector A (CIDEA), and PR domain containing 16 (PRDM16), were increased by this chemical. The underlying molecular mechanism exploration revealed that, in contrast to p38 MAPK, 3-BHA stimulation induced phosphorylation of Smad1/5/8 in an exposure time-dependent manner, suggesting that this chemical-triggered Smad signaling was responsible for the shift of C3H10T1/2 MSC differentiation from a brown to white-like phenotype. The finding herein, for the first time, revealed the perturbation of 3-BHA in the development of brown adipocytes, uncovering new knowledge about the obesogenic potential of this emerging chemical of concern.
RESUMO
Arabidopsis PHO1;H10 is a member of the PHO1 gene family with SPX and EXS domains, and its functions remain largely unknown. As shown in PCSD database, the upstream region of PHO1;H10 gene is in the active chromatin states, with high DHS accessibility and binding sites of multiple transcription factors, especially ABI5, SPCH and HY5. Co-expression network and data-mining analyses showed PHO1;H10 and co-expression genes were with activation under high light stress. We did wet-lab experiments, and found that the detached leaves of PHO1;H10 overexpression lines accumulated more anthocyanin than those of WT and mutant under high light treatment. RNA-seq results showed overexpression of PHO1;H10 up-regulated many anthocyanin biosynthetic genes. The GSEA analysis result showed that the functional module related to anthocyanin pathway was significantly enriched. In summary, we conducted systems biology approach, combining dry- and wet-lab analyses, and discovered that PHO1;H10 might play an essential role during modulating high light-induced anthocyanin accumulation in the Arabidopsis detached leaves.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Antocianinas , Biologia de Sistemas , Folhas de Planta/genética , Folhas de Planta/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
We isolated a novel reassortant influenza A(H10N7) virus from a harbor seal in British Columbia, Canada, that died from bronchointerstitial pneumonia. The virus had unique genome constellations involving lineages from North America and Eurasia and polymerase basic 2 segment D701N mutation, associated with adaptation to mammals.
Assuntos
Vírus da Influenza A Subtipo H10N7 , Influenza Aviária , Influenza Humana , Infecções por Orthomyxoviridae , Phoca , Animais , Colúmbia Britânica/epidemiologia , Vírus de DNA , Humanos , Vírus da Influenza A Subtipo H10N7/genética , Influenza Humana/epidemiologia , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/veterinária , Filogenia , Vírus Reordenados/genéticaRESUMO
More than 90% of ovarian cancer deaths are due to relapse following development of chemoresistance. Our main objective is to better understand the molecular mechanism underlying paclitaxel resistance (taxol resistance, Txr) in ovarian cancer. Here, we observed that the linker histone H1.0 is upregulated in paclitaxel-resistant ovarian cancer cells. Knockdown of H1.0 significantly downregulates the androgen receptor (AR) and sensitizes paclitaxel-resistant SKOV3/Txr and 2774/Txr cell lines to paclitaxel. Conversely, ectopic expression of H1.0 upregulates AR and increases Txr in parental SKOV3 and MDAH2774 cells. Notably, H1.0 upregulation is associated with disease recurrence and poor survival in a subset of ovarian cancer subjects. Inhibition of PI3K significantly reduces H1.0 mRNA and protein levels in paclitaxel-resistant cells, suggesting the involvement of the PI3K/AKT signaling pathway. Knockdown of H1.0 and AR also downregulates the Txr genes ABCB1 and ABCG2 in paclitaxel-resistant cells. Our data show that H1.0 induces GCN5 expression and histone acetylation, thereby enhancing Txr gene transactivation. These findings suggest that Txr in ovarian cancer involves the PI3K/AKT pathway and leads to upregulation of histone H1.0, recruitment of GCN5 and AR, followed by upregulation of a subgroup of Txr genes that include ABCB1 and ABCG2. This study is the first report describing the relationship between histone H1.0 and GCN5 that cooperate to induce AR-dependent Txr in ovarian cancer cells.
Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias Ovarianas , Paclitaxel , Receptores Androgênicos , Fatores de Transcrição de p300-CBP , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Humanos , Recidiva Local de Neoplasia/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Paclitaxel/farmacologia , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Fatores de Transcrição de p300-CBP/genética , Fatores de Transcrição de p300-CBP/metabolismoRESUMO
Obesogens are a subset of endocrine disruptor chemicals (EDCs) that cause obesity. The typical EDC 4-nonylphenol (4-NP) has been identified as an obesogen. However, the in vitro effects of 4-NP on adipogenesis remain unclear. In this study, 3T3-L1 preadipocytes and C3H/10T1/2 mesenchymal stem cells (MSCs) were used to investigate the influence of 4-NP on adipogenesis. The differentiation protocols for 3T3-L1 preadipocytes and C3H/10T1/2 MSCs took 8 and 12 days, respectively, beginning at Day 0. In differentiated 3T3-L1 preadipocytes, 20 µM 4-NP decreased cell viability on Days 4 and 8. Exposure to 4-NP inhibited triglyceride (TG) accumulation and adipogenic marker expression on Days 0-8, but the inhibitory effects were weaker on Days 2-8. The protein expression of pSTAT3 or STAT3 decreased on Days 0-8 and 2-8. Conversely, 4-NP promoted TG accumulation and the adipogenic marker expression in C3H/10T1/2 adipocytes. The opposing effects were attributed to physiological differences between the two cell lines. The 3T3-L1 preadipocytes are dependent on mitotic clonal expansion (MCE) to drive differentiation, while C3H/10T1/2MSCs and human preadipocytes are not. Additionally, 4-NP downregulated ß-catenin expression in C3H/10T1/2 adipocytes. Accordingly, we hypothesized that 4-NP promotes adipogenesis. The role of the canonical Wnt pathway in the promotion of adipogenesis by 4-NP requires further validation. This study provides new insights into the mechanisms and appropriate risk management of 4-NP.
Assuntos
Adipogenia , Células-Tronco Mesenquimais , Células 3T3-L1 , Adipócitos , Animais , Diferenciação Celular , Humanos , Camundongos , FenóisRESUMO
Obesity and its associated metabolic disease do serious harm to human health. The transcriptional cascade network with transcription factors as the core is the focus of current research on adipogenesis and its mechanism. Previous studies have found that HMG domain protein 20A (HMG20A) is highly expressed in the early stage of adipogenic differentiation of porcine intramuscular fat (IMF), which may be involved in regulating adipogenesis. In this study, HMG20A was found to play a key negative regulatory role in adipogenesis. Gain- and loss-of-function studies revealed that HMG20A inhibited the differentiation of SVF cells and C3H10T1/2 cells into mature adipocytes. RNA-seq was used to screen differentially expressed genes after HMG20A knockdown. qRT-PCR and ChIP-PCR confirmed that MEF2C was the real target of HMG20A, and HMG20A played a negative regulatory role through MEF2C. HMG20A binding protein LSD1 was found to alleviate the inhibitory effect of HMG20A on adipogenesis. Further studies showed that HMG20A could cooperate with LSD1 to increase the H3K4me2 of the MEF2C promoter and then increase the expression of MEF2C. Collectively, these findings highlight a role for HMG20A-dependent transcriptional and epigenetic regulation in adipogenesis.
Assuntos
Adipócitos , Adipogenia , Adipócitos/metabolismo , Adipogenia/genética , Animais , Diferenciação Celular/genética , Epigênese Genética , Proteínas de Grupo de Alta Mobilidade/genética , Histona Desmetilases/genética , Humanos , Fatores de Transcrição MEF2/genética , Fatores de Transcrição MEF2/metabolismo , Suínos , Fatores de Transcrição/metabolismoRESUMO
In this paper we derive a generating series for the number of cellular complexes known as pavings or three-dimensional maps, on n darts, thus solving an analogue of Tutte's problem in dimension three. The generating series we derive also counts free subgroups of index n in Δ + = Z 2 ∗ Z 2 ∗ Z 2 via a simple bijection between pavings and finite index subgroups which can be deduced from the action of Δ + on the cosets of a given subgroup. We then show that this generating series is non-holonomic. Furthermore, we provide and study the generating series for isomorphism classes of pavings, which correspond to conjugacy classes of free subgroups of finite index in Δ + . Computational experiments performed with software designed by the authors provide some statistics about the topology and combinatorics of pavings on n ≤ 16 darts.
RESUMO
In this study, we investigated the effect of Biochanin A (BioA), an O-methylated isoflavone on the brown-fat phenotype formation and on the associated thermogenic program including mitochondrial biogenesis and lipolysis in C3H10T1/2 MSCs. Our data demonstrates that Treatment with BioA in an adipogenic differentiation cocktail induced formation of brown-fat-like adipocytes from C3H10T1/2 MSCs without treatment with a known browning inducer (rosiglitazone or T3) at an early stage of differentiation. The formation of brown-fat-like adipocytes by BioA treatment was evidenced by upregulation of key thermogenic markers: Ucp1, Pgc1α, Prdm16, and Pparγ. BioA also increased the expression of beige (Cd137 and Fgf21) and brown (Elovl3 and Zic1)-specific markers. Additionally, BioA treatment promoted mitochondrial biogenesis, judging by the upregulation of genes; Cox8b, Cidea, Dio2, Sirt1, Opa1, and Fis1. BioA treatment increased the amount of mitochondrial DNA and its encoded proteins: oxidative phosphorylation complexes (I-V); this change was associated with high oxygen consumption by C3H10T1/2 MSCs. A small-interfering-RNA-induced gene knockdown and experiments with dorsomorphin-driven competitive inhibition revealed that BioA exerts the thermogenic action via activation of AMPK signaling. Our study shows the mechanism of BioA-induced promotion of a brown-fat phenotype. Nonetheless, clinical research is necessary to validate BioA as a brown-fat-like signature inducer.
Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Adipócitos Marrons/efeitos dos fármacos , Anticarcinógenos/uso terapêutico , Genisteína/uso terapêutico , Células-Tronco Mesenquimais/efeitos dos fármacos , Animais , Anticarcinógenos/farmacologia , Diferenciação Celular , Genisteína/farmacologia , Camundongos , Biogênese de Organelas , Transdução de Sinais , TransfecçãoRESUMO
In disease model systems, random noises and time delay factors play key role in interpreting disease dynamics to comprehend deeper insights into the course of dynamics. An endeavor to forecast intercellular behavioral dynamics of SARS-CoV-2 virus via Infection model with responsive host immune mechanisms forms the crux of this research study. Incorporation of time delay factor into infection transmission rates in noisy system epitomizes spectacular view on internal viral dynamics and stability properties are rigorously analyzed around equilibrium steady states to probe feasible strategies in mitigating rapid spread. Efforts to perceive inocular view on infection dynamics are not limited to theoretical frontiers but are substantiated with empirically simulated outcomes and visualized as graphical upshots. Discussions on numerical investigations emphasized shorter incubation periods and vaccination at pertinent time intervals to restrain massive spread and exhibit total immunity against SARS-CoV-2 infections.
RESUMO
We propose a refined version of the stochastic SEIR model for epidemic of the new corona virus SARS-Cov-2, causing the COVID-19 disease, taking into account the spread of the virus due to the regular infected individuals (transmission coefficient ß ), hospitalized individuals (transmission coefficient l ß , l > 0 ) and superspreaders (transmission coefficient ß ' ). The model is constructed from the corresponding ordinary differential model by introducing two independent environmental white noises in transmission coefficients for above mentioned classes - one noise for infected and hospitalized individuals and the other for superspreaders. Therefore, the model is defined as a system of stochastic differential equations driven by two independent standard Brownian motions. Existence and uniqueness of the global positive solution is proven, and conditions under which extinction and persistence in mean hold are given. The theoretical results are illustrated via numerical simulations.
RESUMO
Subtype H10 influenza A viruses (IAVs) have been recovered from domestic poultry and various aquatic bird species, and sporadic transmission of these IAVs from avian species to mammals (i.e., human, seal, and mink) are well documented. In 2015, we isolated four H10N7 viruses from gulls in Iceland. Genomic analyses showed four gene segments in the viruses were genetically associated with H10 IAVs that caused influenza outbreaks and deaths among European seals in 2014. Antigenic characterization suggested minimal antigenic variation among these H10N7 isolates and other archived H10 viruses recovered from human, seal, mink, and various avian species in Asia, Europe, and North America. Glycan binding preference analyses suggested that, similar to other avian-origin H10 IAVs, these gull-origin H10N7 IAVs bound to both avian-like alpha 2,3-linked sialic acids and human-like alpha 2,6-linked sialic acids. However, when the gull-origin viruses were compared with another Eurasian avian-origin H10N8 IAV, which caused human infections, the gull-origin virus showed significantly higher binding affinity to human-like glycan receptors. Results from a ferret experiment demonstrated that a gull-origin H10N7 IAV replicated well in turbinate, trachea, and lung, but replication was most efficient in turbinate and trachea. This gull-origin H10N7 virus can be transmitted between ferrets through the direct contact and aerosol routes, without prior adaptation. Gulls share their habitat with other birds and mammals and have frequent contact with humans; therefore, gull-origin H10N7 IAVs could pose a risk to public health. Surveillance and monitoring of these IAVs at the wild bird-human interface should be continued.IMPORTANCE Subtype H10 avian influenza A viruses (IAVs) have caused sporadic human infections and enzootic outbreaks among seals. In the fall of 2015, H10N7 viruses were recovered from gulls in Iceland, and genomic analyses showed that the viruses were genetically related with IAVs that caused outbreaks among seals in Europe a year earlier. These gull-origin viruses showed high binding affinity to human-like glycan receptors. Transmission studies in ferrets demonstrated that the gull-origin IAV could infect ferrets, and that the virus could be transmitted between ferrets through direct contact and aerosol droplets. This study demonstrated that avian H10 IAV can infect mammals and be transmitted among them without adaptation. Thus, avian H10 IAV is a candidate for influenza pandemic preparedness and should be monitored in wildlife and at the animal-human interface.