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1.
Commun Biol ; 7(1): 363, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38521877

RESUMO

The placenta is a unique organ for ensuring normal embryonic growth in the uterine. Here, we found that maternal RNA transcription in Dlk1-Dio3 imprinted domain is essential for placentation. PolyA signals were inserted into Gtl2 to establish a mouse model to prevent the expression of maternal RNAs in the domain. The maternal allele knock-in (MKI) and homozygous (HOMO) placentas showed an expanded junctional zone, reduced labyrinth and poor vasculature impacting both fetal and maternal blood spaces. The MKI and HOMO models displayed dysregulated gene expression in the Dlk1-Dio3 domain. In situ hybridization detected Dlk1, Gtl2, Rtl1, miR-127 and Rian dysregulated in the labyrinth vasculature. MKI and HOMO induced Dlk1 to lose imprinting, and DNA methylation changes of IG-DMR and Gtl2-DMR, leading to abnormal gene expression, while the above changes didn't occur in paternal allele knock-in placentas. These findings demonstrate that maternal RNAs in the Dlk1-Dio3 domain are involved in placental vasculature, regulating gene expression, imprinting status and DNA methylation.


Assuntos
Proteínas de Ligação ao Cálcio , Impressão Genômica , RNA Longo não Codificante , Animais , Feminino , Camundongos , Gravidez , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Placenta/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
2.
Can Respir J ; 2023: 3291957, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074219

RESUMO

Objective. Dysregulation of epithelial-mesenchymal transition (EMT) in the airway epithelium is associated with airway remodeling and the progression of pulmonary fibrosis. Many treatments have been shown to inhibit airway remodeling and pulmonary fibrosis progression in asthma and chronic obstructive pulmonary disease (COPD) by regulating EMT and have few side effects. This review aimed to describe the development of airway remodeling through the EMT pathway, as well as the potential therapeutic targets in these pathways. Furthermore, this study aimed to review the current research on drugs to treat airway remodeling and their effects on the EMT pathway. Findings. The dysregulation of EMT was associated with airway remodeling in various respiratory diseases. The cytokines released during inflammation may induce EMT and subsequent airway remodeling. Various drugs, including herbal formulations, specific herbal compounds, cytokines, amino acid or protein inhibitors, microRNAs, and vitamins, may suppress airway remodeling by inhibiting EMT-related pathways.


Assuntos
Asma , Fibrose Pulmonar , Humanos , Fibrose Pulmonar/tratamento farmacológico , Remodelação das Vias Aéreas , Asma/tratamento farmacológico , Transição Epitelial-Mesenquimal/fisiologia , Citocinas
3.
Cell Mol Life Sci ; 80(10): 307, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37768430

RESUMO

N-acetyltransferase 10 (NAT10)-mediated N4-acetylcytidine (ac4C) modification is crucial for mRNA stability and translation efficiency, yet the underlying function in mammalian preimplantation embryos remains unclear. Here, we characterized the ac4C modification landscape in mouse early embryos and found that the majority of embryos deficient in ac4C writer-NAT10 failed to develop into normal blastocysts. Through single-cell sequencing, RNA-seq, acetylated RNA immunoprecipitation combined with PCR (acRIP-PCR), and embryonic phenotype monitoring, Nop2 was screened as a target gene of Nat10. Mechanistically, Nat10 knockdown decreases the ac4C modification on Nop2 mRNA and reduces RNA and protein abundance by affecting the mRNA stability of Nop2. Then, depletion of NOP2 may inhibit the translation of transcription factor TEAD4, resulting in defective expression of the downstream lineage-specific gene Cdx2, and ultimately preventing blastomeres from undergoing the trophectoderm (TE) fate. However, exogenous Nop2 mRNA partially reverses this abnormal development. In conclusion, our findings demonstrate that defective ac4C modification of Nop2 mRNA hinders the morula-to-blastocyst transition by influencing the first cell fate decision in mice.

4.
Immunobiology ; 228(6): 152731, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37607433

RESUMO

Food allergies, which lead to life-threatening acute symptoms, are considered an important public health problem. Therefore, it is essential to develop efficient preventive and treatment measures. We developed a crude peanut protein extract (PPE)-induced allergy mouse model to investigate the effects of lycopene on peanut allergy. Mice were divided into four groups: 5 mg/kg lycopene, 20 mg/kg lycopene, no treatment, and control groups. Serum inflammatory factors were detected using enzyme-linked immunosorbent assay. In addition, pathology and immunohistochemistry analyses were used to examine the small intestine of mice. We found that lycopene decreased PPE-specific immunoglobulin E (IgE) and IL-13 levels in the serum, relieved small intestine inflammation, attenuated the production of histamine and mouse mast cell protease-1, and downregulated PI3K and AKT1 expression in the small intestine tissues of mice allergic to peanuts. Our results suggest that lycopene can ameliorate allergy by attenuating the PI3K/AKT pathway and the anaphylactic reactions mediated by PPE-specific IgE.


Assuntos
Hipersensibilidade Alimentar , Hipersensibilidade a Amendoim , Camundongos , Animais , Arachis/metabolismo , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Licopeno , Camundongos Endogâmicos BALB C , Hipersensibilidade Alimentar/tratamento farmacológico , Hipersensibilidade a Amendoim/tratamento farmacológico , Hipersensibilidade a Amendoim/patologia , Imunoglobulina E , Alérgenos
5.
Genes (Basel) ; 14(6)2023 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-37372444

RESUMO

Meg8-DMR is the first maternal methylated DMR to be discovered in the imprinted Dlk1-Dio3 domain. The deletion of Meg8-DMR enhances the migration and invasion of MLTC-1 depending on the CTCF binding sites. However, the biological function of Meg8-DMR during mouse development remains unknown. In this study, a CRISPR/Cas9 system was used to generate 434 bp genomic deletions of Meg8-DMR in mice. High-throughput and bioinformatics profiling revealed that Meg8-DMR is involved in the regulation of microRNA: when the deletion was inherited from the mother (Mat-KO), the expression of microRNA was unchanged. However, when the deletion occurred from the father (Pat-KO) and homozygous (Homo-KO), the expression was upregulated. Then, differentially expressed microRNAs (DEGs) were identified between WT with Pat-KO, Mat-KO, and Homo-KO, respectively. Subsequently, these DEGs were subjected to the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) term enrichment analysis to explore the functional roles of these genes. In total, 502, 128, and 165 DEGs were determined. GO analysis showed that these DEGs were mainly enriched in axonogenesis in Pat-KO and Home-KO, while forebrain development was enriched in Mat-KO. Finally, the methylation levels of IG-DMR, Gtl2-DMR, and Meg8-DMR, and the imprinting status of Dlk1, Gtl2, and Rian were not affected. These findings suggest that Meg8-DMR, as a secondary regulatory region, could regulate the expression of microRNAs while not affecting the normal embryonic development of mice.


Assuntos
MicroRNAs , Animais , Feminino , Camundongos , Gravidez , Proteínas de Ligação ao Cálcio/genética , Metilação de DNA/genética , Desenvolvimento Embrionário/genética , Impressão Genômica , Peptídeos e Proteínas de Sinalização Intercelular/genética , MicroRNAs/genética , Sequências Reguladoras de Ácido Nucleico
6.
Int J Mol Sci ; 23(15)2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35955961

RESUMO

The Dlk1-Dio3 imprinted domain on mouse chromosome 12 contains three well-characterized paternally methylated differentially methylated regions (DMRs): IG-DMR, Gtl2-DMR, and Dlk1-DMR. These DMRs control the expression of many genes involved in embryonic development, inherited diseases, and human cancer in this domain. The first maternal methylation DMR discovered in this domain was the Meg8-DMR, the targets and biological function of which are still unknown. Here, using an enhancer-blocking assay, we first dissected the functional parts of the Meg8-DMR and showed that its insulator activity is dependent on the CCCTC-binding factor (CTCF) in MLTC-1. Results from RNA-seq showed that the deletion of the Meg8-DMR and its compartment CTCF binding sites, but not GGCG repeats, lead to the downregulation of numerous genes on chromosome 12, in particular the drastically reduced expression of Dlk1 and Rtl1 in the Dlk1-Dio3 domain, while differentially expressed genes are enriched in the MAPK pathway. In vitro assays revealed that the deletion of the Meg8-DMR and CTCF binding sites enhances cell migration and invasion by decreasing Dlk1 and activating the Notch1-Rhoc-MAPK/ERK pathway. These findings enhance research into gene regulation in the Dlk1-Dio3 domain by indicating that the Meg8-DMR functions as a long-range regulatory element which is dependent on CTCF binding sites and affects multiple genes in this domain.


Assuntos
Impressão Genômica , RNA Longo não Codificante , Animais , Sítios de Ligação , Proteínas de Ligação ao Cálcio/genética , Metilação de DNA , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Camundongos , Gravidez , RNA Longo não Codificante/genética
7.
Nat Cell Biol ; 24(7): 1141-1153, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35787683

RESUMO

Mutagenic purine-pyrimidine repeats can adopt the left-handed Z-DNA conformation. DNA breaks at potential Z-DNA sites can lead to somatic mutations in cancer or to germline mutations that are transmitted to the next generation. It is not known whether any mechanism exists in the germ line to control Z-DNA structure and DNA breaks at purine-pyrimidine repeats. Here we provide genetic, epigenomic and biochemical evidence for the existence of a biological process that erases Z-DNA specifically in germ cells of the mouse male foetus. We show that a previously uncharacterized zinc finger protein, ZBTB43, binds to and removes Z-DNA, preventing the formation of DNA double-strand breaks. By removing Z-DNA, ZBTB43 also promotes de novo DNA methylation at CG-containing purine-pyrimidine repeats in prospermatogonia. Therefore, the genomic and epigenomic integrity of the species is safeguarded by remodelling DNA structure in the mammalian germ line during a critical window of germline epigenome reprogramming.


Assuntos
DNA Forma Z , Animais , DNA/metabolismo , Metilação de DNA , DNA Forma Z/metabolismo , Epigenoma , Células Germinativas/metabolismo , Masculino , Mamíferos/metabolismo , Camundongos , Conformação de Ácido Nucleico , Purinas/metabolismo , Pirimidinas
8.
J Asthma Allergy ; 15: 645-664, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35603013

RESUMO

Purpose: Food allergy-induced autism-like behavior has been increasing for decades, but the causal drivers of this association are unclear. We sought to test the association of gut microbiota and mammalian/mechanistic target of rapamycin (mTOR) signaling with cow's milk allergy (CMA)-induced autism pathogenesis. Methods: Mice were sensitized intragastrically with whey protein containing cholera toxin before sensitization on intraperitoneal injection with whey-containing alum, followed by intragastric allergen challenge to induce experimental CMA. The food allergic immune responses, ASD-like behavioral tests and changes in the mTOR signaling pathway and gut microbial community structure were performed. Results: CMA mice showed autism-like behavioral abnormalities and several distinct biomarkers. These include increased levels of 5-hydroxymethylcytosine (5-hmC) in the hypothalamus; c-Fos were predominantly located in the region of the lateral orbital prefrontal cortex (PFC), but not ventral; decreased serotonin 1A in amygdala and PFC. CMA mice exhibited a specific microbiota signature characterized by coordinate changes in the abundance of taxa of several bacterial genera, including the Lactobacillus. Interestingly, the changes were accompanied by promoted mTOR signaling in the brain of CMA mice. Conclusion: We found that disease-associated microbiota and mTOR activation may thus play a pathogenic role in the intestinal, immunological, and psychiatric Autism Spectrum Disorder (ASD)-like symptoms seen in CAM associated autism. However, this is only a preliminary study, and their mechanisms require further investigation.

9.
Cell Death Dis ; 13(5): 483, 2022 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-35595748

RESUMO

Exploring the epigenetic regulation mechanism of colorectal cancer (CRC) from the perspective of N6-methyladenosine (m6A) modification may provide a new target for tumor therapy. Analysis using high-throughput RNA-seq profile from TCGA found that the gene expression of Methyltransferase-like 3 (METTL3) was significantly upregulated among 20 m6A binding proteins in CRC, which was also validated in CRC cancer tissues and cell lines. Moreover, transcriptome sequencing in METTL3 knockdown cells using CRISPR/Cas9 editing suggested that EphA2 and VEGFA were differential expression, which were enriched in the vasculature development, PI3K/AKT and ERK1/2 signal pathway through the functional enrichment analysis. The results in vitro revealed that METTL3 as the m6A "writers" participates the methylation of EphA2 and VEGFA, which were recognized by the m6A "readers", insulin-like growth factor 2 mRNA binding protein 2/3 (IGF2BP2/3), to prevent their mRNA degradation. In addition, EphA2 and VEGFA targeted by METTL3 via different IGF2BP-dependent mechanisms were found to promote vasculogenic mimicry (VM) formation via PI3K/AKT/mTOR and ERK1/2 signaling in CRC. The study suggests that intervention with m6A-binding proteins (METTL3 and IGF2BP2/3) may provide a potential diagnostic or prognostic target of VM-based anti-metastasis drugs for CRC.


Assuntos
Neoplasias Colorretais , Proteínas de Ligação a RNA , Receptor EphA2 , Fator A de Crescimento do Endotélio Vascular , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Epigênese Genética , Humanos , Sistema de Sinalização das MAP Quinases/genética , Metiltransferases/genética , Metiltransferases/metabolismo , Neovascularização Patológica , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas de Ligação a RNA/metabolismo , Receptor EphA2/genética , Receptor EphA2/metabolismo , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Front Pharmacol ; 13: 838261, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35370734

RESUMO

Depression is a prevalent psychiatric disorder. Microglial state transition has been found in many neurological disorders including depression. Gypenosides (Gypenosides I-LXXVIII, Gps) are saponin extracts isolated from the traditional Chinese herb Gynostemma pentaphyllum (Thunb.) Makino that exert anti-inflammatory and neuroprotective activities and regulate depression-like behaviors. However, its effect on microglial state transition in depression remains unknown. We aimed to evaluate the potential relationship between Gps and TLR4/MyD88/NF-κB signaling in microglial state transition in vitro and in vivo. First, BV-2 cells (microglial cell line) were exposed to lipopolysaccharides (LPS) and treated with 10 or 5 µg/ml Gps. Second, the chronic unpredictable mild stress (CUMS)-induced depression mouse model was used to investigate the antidepressant-like behaviors effects of Gps (100 or 50 mg/kg). We determined depression-like behaviors using the open-field test (OFT), forced swim test (FST), and sucrose preference test (SPT). Proteins and inflammatory factors in the TLR4/MyD88/NF-κB signaling pathway and the different microglial reaction states markers were subsequently conducted using enzyme-linked immunosorbent assay, immunocytochemistry, immunofluorescence, qPCR, or Western blotting analyses to evaluate the anti-inflammatory and antidepressant properties of Gps and the underlying molecular mechanisms. We found that Gps regulated the microglial cell line state transition in LPS-exposed BV-2 cells, as evidenced by the significantly decreased expression of inflammatory parameters iNOS, IL-1ß, IL-6, and TNF-α and significantly promoted anti-inflammatory microglial phenotypes markers CD206 (Mrc1) and IL-10. More importantly, Gps protected against the loss of monoamine neurotransmitters and depression-like behavior in a mouse model of depression, which was accompanied by a regulation of the microglial state transition. Mechanistically, Gps inhibited TLR4/MyD88/NF-κB signaling, which reduced the release of downstream inflammatory cytokines (IL-1ß, IL-6, and TNF-α) and promoted microglial phenotype transition, which all together contributed to the antidepressant effect. Our results suggest that Gps prevents depression-like behaviors by regulating the microglial state transition and inhibiting the TLR4/MyD88/NF-κB signaling pathway. Thus, Gps could be a promising therapeutic strategy to prevent and treat depression-like behaviors and other psychiatric disorders.

11.
RSC Adv ; 12(14): 8737-8742, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35424809

RESUMO

Baicalin has been demonstrated to have multiple pharmacological activities but low solubility. Various baicalin hydrogels have been used to improve its solubility and break its limitation in clinical applications. However, traditional baicalin hydrogels contain numerous ingredients and usually show low baicalin loading capacity. Herein, we discovered a dynamic covalent hydrogel only consisting of baicalin and inorganic borate, in which baicalin is considered as the carrier and drug without other ingredients. The dynamic boronate bonds endow the hydrogel with excellent degradability and multi-stimuli-responsiveness. Moreover, the hydrogel displayed remarkable thixotropy, moldability, and self-healing properties. And the biocompatible baicalin hydrogel exhibited significant antibacterial activities, and can be considered as a potential drug delivery system for biomedical applications.

12.
J Healthc Eng ; 2022: 9248674, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35340244

RESUMO

The first reported case of coronavirus disease 2019 (COVID-19) occurred in Wuhan, Hubei, China. Thereafter, it spread through China and worldwide in only a few months, reaching a pandemic level. It can cause severe respiratory illnesses such as pneumonia and lung failure. Since the onset of the disease, the rapid response and intervention of traditional Chinese medicine (TCM) have played a significant role in the effective control of the epidemic. Yinqiaosan (YQS) was used to treat COVID-19 pneumonia, with good curative effects. However, a systematic overview of its active compounds and the therapeutic mechanisms underlying its action has yet to be performed. The purpose of the current study is to explore the compounds and mechanism of YQS in treating COVID-19 pneumonia using system pharmacology. A system pharmacology method involving drug-likeness assessment, oral bioavailability forecasting, virtual docking, and network analysis was applied to estimate the active compounds, hub targets, and key pathways of YQS in the treatment of COVID-19 pneumonia. With this method, 117 active compounds were successfully identified in YQS, and 77 potential targets were obtained from the targets of 95 compounds and COVID-19 pneumonia. The results show that YQS may act in treating COVID-19 pneumonia and its complications (atherosclerosis and nephropathy) through Kaposi sarcoma-related herpesvirus infection and the AGE-RAGE signaling pathway in diabetic complications and pathways in cancer. We distinguished the hub molecular targets within pathways such as TNF, GAPDH, MAPK3, MAPK1, EGFR, CASP3, MAPK8, mTOR, IL-2, and MAPK14. Five of the more highly active compounds (acacetin, kaempferol, luteolin, naringenin, and quercetin) have anti-inflammatory and antioxidative properties. In summary, by introducing a systematic network pharmacology method, our research perfectly forecasts the active compounds, potential targets, and key pathways of YQS applied to COVID-19 and helps to comprehensively clarify its mechanism of action.


Assuntos
Tratamento Farmacológico da COVID-19 , Medicamentos de Ervas Chinesas , Anti-Inflamatórios , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Medicina Tradicional Chinesa
13.
Front Immunol ; 12: 736479, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34804018

RESUMO

Airway remodeling is associated with dysregulation of epithelial-mesenchymal transition (EMT) in patients with asthma. Sinomenine (Sin) is an effective, biologically active alkaloid that has been reported to suppress airway remodeling in mice with asthma. However, the molecular mechanisms behind this effect remain unclear. We aimed to explore the potential relationship between Sin and EMT in respiratory epithelial cells in vitro and in vivo. First, 16HBE cells were exposed to 100 µg/mL LPS and treated with 200 µg/mL Sin. Cell proliferation, migration, and wound healing assays were performed to evaluate EMT, and EMT-related markers were detected using Western blotting. Mice with OVA-induced asthma were administered 35 mg/kg or 75 mg/kg Sin. Airway inflammation and remodeling detection experiments were performed, and EMT-related factors and proteins in the TGF-ß1 pathway were detected using IHC and Western blotting. We found that Sin suppressed cell migration but not proliferation in LPS-exposed 16HBE cells. Sin also inhibited MMP7, MMP9, and vimentin expression in 16HBE cells and respiratory epithelial cells from mice with asthma. Furthermore, it decreased OVA-specific IgE and IL-4 levels in serum, relieved airway remodeling, attenuated subepithelial collagen deposition, and downregulating TGF-ß1and Smad3 expression in mice with asthma. Our results suggest that Sin suppresses EMT by inhibiting IL-4 and downregulating TGF-ß1 and Smad3 expression.


Assuntos
Remodelação das Vias Aéreas/efeitos dos fármacos , Antiasmáticos/farmacologia , Asma/tratamento farmacológico , Células Epiteliais/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Morfinanos/farmacologia , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Asma/induzido quimicamente , Asma/metabolismo , Asma/patologia , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Humanos , Interleucina-4/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Camundongos Endogâmicos BALB C , Ovalbumina , Transdução de Sinais
14.
Zhongguo Zhong Yao Za Zhi ; 46(4): 757-761, 2021 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-33645077

RESUMO

This article aims to provide a good experimental method for the study of drug treatment of ulcerative colitis. According to the characteristics of ulcerative colitis's clinical symptoms, common ulcerative colitis animal models were analyzed. Based on the characteristics of clinical symptoms of traditional Chinese medicine and Western medicine for ulcerative colitis disease, the existing commonly used animal models of ulcerative colitis were analyzed to summarize the current matching degree, advantages and disadvantages of the exi-sting animal models of ulcerative colitis and clinical symptoms. At present, studies on ulcerative colitis mainly adopt four types of induction modeling methods, such as immunization, chemical stimulation, compound method and gene model. There are many reported methods of colitis modeling, but no model can reflect the characteristics of clinical symptoms of ulcerative colitis treated with Western or Chinese medicine. This article summarizes the characteristics, clinically relevant symptoms and applicable scope of immunization, chemical stimulation, compound method, and gene model, so as to provide a reliable animal model for subsequent studies of prevention and treatment of colitis.


Assuntos
Charadriiformes , Colite Ulcerativa , Medicina , Animais , China , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/genética , Modelos Animais de Doenças , Medicina Tradicional Chinesa
15.
Cell Death Dis ; 12(3): 264, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712565

RESUMO

Super-enhancers or stretch enhancers (SEs) consist of large clusters of active transcription enhancers which promote the expression of critical genes that define cell identity during development and disease. However, the role of many super-enhancers in tumor cells remains unclear. This study aims to explore the function and mechanism of a new super-enhancer in various tumor cells. A new super-enhancer that exists in a variety of tumors named EphA2-Super-enhancer (EphA2-SE) was found using multiple databases and further identified. CRISPR/Cas9-mediated deletion of EphA2-SE results in the significant downregulation of its target gene EphA2. Mechanistically, we revealed that the core active region of EphA2-SE comprises E1 component enhancer, which recruits TCF7L2 and FOSL2 transcription factors to drive the expression of EphA2, induce cell proliferation and metastasis. Bioinformatics analysis of RNA-seq data and functional experiments in vitro illustrated that EphA2-SE deletion inhibited cell growth and metastasis by blocking PI3K/AKT and Wnt/ß-catenin pathway in HeLa, HCT-116 and MCF-7 cells. Overexpression of EphA2 in EphA2-SE-/- clones rescued the effect of EphA2-SE deletion on proliferation and metastasis. Subsequent xenograft animal model revealed that EphA2-SE deletion suppressed tumor proliferation and survival in vivo. Taken together, these findings demonstrate that EphA2-SE plays an oncogenic role and promotes tumor progression in various tumors by recruiting FOSL2 and TCF7L2 to drive the expression of oncogene EphA2.


Assuntos
Elementos Facilitadores Genéticos , Antígeno 2 Relacionado a Fos/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias/genética , Receptor EphA2/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Células A549 , Animais , Movimento Celular , Proliferação de Células , Antígeno 2 Relacionado a Fos/metabolismo , Células HCT116 , Células HeLa , Humanos , Células MCF-7 , Camundongos Nus , Metástase Neoplásica , Neoplasias/metabolismo , Neoplasias/patologia , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor EphA2/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo , Via de Sinalização Wnt
16.
Cell Death Differ ; 27(4): 1431-1446, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31700144

RESUMO

Increasing evidence has indicated that long noncoding RNAs (lncRNAs) play important roles in human diseases, including cancer; however, only a few of them have been experimentally validated and functionally annotated. Here, we identify a novel lncRNA that we term HITT (HIF-1α inhibitor at translation level). HITT is commonly decreased in multiple human cancers. Decreased HITT is associated with advanced stages of colon cancer. Restoration of the expression of HITT in cancer cells inhibits angiogenesis and tumor growth in vivo in an HIF-1α-dependent manner. Further study reveals that HITT inhibits HIF-1α expression, mainly by interfering with its translation. Mechanically, HITT titrates away YB-1 from the 5'-UTR of HIF-1α mRNA via a high-stringency YB-1-binding motif. The reverse correlation between HITT and HIF-1α expression is further validated in human colon cancer tissues. Moreover, HITT is one of the most altered lncRNAs upon the hypoxic switch and HITT downregulation is required for hypoxia-induced HIF-1α expression. We further demonstrate that HITT and HIF-1α form an autoregulatory feedback loop where HIF-1α destabilizes HITT by inducing MiR-205, which directly targets HITT for degradation. Together, these results expand our understanding of the cancer-associated functions of lncRNAs, highlighting the HITT-HIF-1α axis as constituting an additional layer of regulation of angiogenesis and tumor growth, with potential implications for therapeutic targeting.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neovascularização Patológica/genética , RNA Longo não Codificante/metabolismo , Animais , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação para Baixo/genética , Retroalimentação Fisiológica , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Camundongos Nus , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias/genética , Neoplasias/patologia , Biossíntese de Proteínas , Estabilidade de RNA/genética , RNA Longo não Codificante/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteína 1 de Ligação a Y-Box/metabolismo
17.
Biochem Biophys Res Commun ; 520(3): 619-626, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31623832

RESUMO

Elevated plasma free fatty acid (FFA) levels are associated with insulin resistance and can cause lipotoxicity in skeletal muscles. In response to FFAs, skeletal muscle can secrete a variety of cytokines. Irisin, one such muscle-secreted cytokine, can improve glucose tolerance, glucose uptake, and lipid metabolism. It is produced by the transmembrane protein fibronectin type Ⅲ domain containing 5 (FNDC5) by specific proteases. The purpose of this study was to investigate the regulatory mechanisms of the FNDC5 response to palmitate and their relationships with insulin resistance in C2C12 myotubes. RNA sequencing analysis results from C2C12 myotubes treated with palmitate showed that palmitate could activate the TGF-ß signaling pathway. Palmitate directly affected the expression of Smad3, but not its phosphorylation level, in C2C12 myotubes. Furthermore, knockdown and knockout of Smad3 alleviated the inhibitory effect of palmitate on the expression of FNDC5. In contrast, overexpression of Smad3 aggravated the inhibition of FNDC5 expression. There is a Smad3 binding motif in the -660 bp to -649 bp region of the Fndc5 promoter. CRISPR/Cas9 knockout of this region also alleviated the inhibition of FNDC5 expression in response to palmitate. More importantly, inhibition of FNDC5 expression mediated by Smad3 led to a decrease in insulin sensitivity in C2C12 myotubes. Collectively, these findings suggest that palmitate could induce insulin resistance through Smad3-mediated down-regulation of the Fndc5 gene.


Assuntos
Fibronectinas/metabolismo , Resistência à Insulina/fisiologia , Fibras Musculares Esqueléticas/metabolismo , Ácido Palmítico/metabolismo , Proteína Smad3/metabolismo , Animais , Sítios de Ligação/genética , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Fibronectinas/antagonistas & inibidores , Fibronectinas/genética , Técnicas de Silenciamento de Genes , Técnicas de Inativação de Genes , Camundongos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Ácido Palmítico/farmacologia , Regiões Promotoras Genéticas , Transdução de Sinais/efeitos dos fármacos , Proteína Smad3/antagonistas & inibidores , Proteína Smad3/genética , Fator de Crescimento Transformador beta/metabolismo
18.
Am J Physiol Endocrinol Metab ; 316(6): E1081-E1092, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30964708

RESUMO

Musclin is a muscle-secreted cytokine that disrupts glucose uptake and glycogen synthesis in type 2 diabetes. The purpose of this study was to investigate the mechanisms responsible for the regulation of musclin gene expression in response to treatment with palmitate. RNA sequencing results showed that biological processes activated by palmitate are mainly enriched in endoplasmic reticulum (ER) stress. The protein kinase RNA-like ER kinase (PERK) signaling pathway is involved in the regulation of musclin expression induced by palmitate. Chromatin immunoprecipitation data showed that activating transcription factor 4 (ATF4)-downstream of PERK-bound to the promoter of the C/EBPß gene. Notably, C/EBPß also contains a binding site in the region -94~-52 of the musclin gene promoter. Knockdown or knockout of PERK and ATF4 using short hairpin RNA or CRISPR-Cas9 decreased the expression of C/EBPß and musclin induced by palmitate. Furthermore, knockdown and knockout of C/EBPß alleviated the high expression of musclin in response to treatment with palmitate. Moreover, CRISPR-Cas9 knockout of the region -94~-52 in which C/EBPß binds to the promoter of musclin abrogated the induction of high musclin expression caused by palmitate. Collectively, these findings suggest that treatment with palmitate activates the PERK/ATF4 signaling pathway, which in turn increases the expression of C/EBPß. C/EBPß binds directly to the promoter of the musclin gene and upregulates its expression.


Assuntos
Fator 4 Ativador da Transcrição/efeitos dos fármacos , Proteína beta Intensificadora de Ligação a CCAAT/efeitos dos fármacos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Proteínas Musculares/efeitos dos fármacos , Palmitatos/farmacologia , Fatores de Transcrição/efeitos dos fármacos , eIF-2 Quinase/efeitos dos fármacos , Fator 4 Ativador da Transcrição/metabolismo , Animais , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Linhagem Celular , Técnicas de Silenciamento de Genes , Técnicas de Inativação de Genes , Camundongos , Fibras Musculares Esqueléticas/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Regiões Promotoras Genéticas , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , eIF-2 Quinase/metabolismo
19.
J Sci Food Agric ; 99(10): 4849-4862, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31001831

RESUMO

BACKGROUND: Methionine is an essential sulfur-containing amino acid. To elucidate the influence of l-methionine on activation of the nuclear factor erythroid 2-related factor 2-antioxidant responsive element (Nrf2-ARE) antioxidant pathway to stimulate the endogenous antioxidant activity for depressing reactive oxygen species (ROS)-derived oxidative stress, male Wistar rats were orally administered l-methionine daily for 14 days. RESULTS: With the intake of l-methionine, Nrf2 was activated by l-methionine through depressing Keap1 and Cul3, resulting in upregulation of ARE-driven antioxidant expression (glutamate cysteine ligase catalytic subunit, glutamate cysteine ligase modulatory subunit, glutathione synthase (GS), catalase (CAT), superoxide dismutase (SOD), heme oxygenase 1, NAD(P)H:quinone oxidoreductase 1, glutathione reductase (GR), glutathione S-transferase (GST), glutathione peroxidase (GPx)) with increasing l-methionine availability. Upon activation of Nrf2, glutathione synthesis was increased through upregulated expression of methionine adenosyltransferase, S-adenosylhomocysteine hydrolase, cystathionine ß-synthase, cystathionine γ-lyse, glutamate cysteine ligase (GCL) and GS, while hepatic expressions of methionine sulfoxide reductases (MsrA, MsrB2, MsrB3) and hepatic enzyme activities (CAT, SOD, GCL, GR, GST, GPx) were uniformly stimulated with increasing consumption of l-methionine. As a result, hepatic content of ROS and MDA were effectively reduced by l-methionine intake. CONCLUSION: The present study demonstrates that methionine availability plays a critical role in activation of the Nrf2-ARE pathway to induce an endogenous antioxidant response for depressing ROS-derived oxidative stress, which is primarily attributed to the stimulation of methionine sulfoxide reductase expression and glutathione synthesis. © 2019 Society of Chemical Industry.


Assuntos
Antioxidantes/metabolismo , Metionina/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Ratos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Glutationa , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fígado/metabolismo , Masculino , Fator 2 Relacionado a NF-E2/genética , Ratos/genética , Ratos/crescimento & desenvolvimento , Ratos Wistar
20.
J Biochem Mol Toxicol ; 33(6): e22308, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30770602

RESUMO

Mutations in transforming growth factor beta receptor II (TGFBR2) are detected in up to 30% of overall colorectal cancer (CRC). Dysregulation of some microRNAs participated in the CRC pathogenesis. In this study, we used the gene ontology analyses, the Kyoto Encyclopedia of Genes and Genomes pathway analyses and gene set enrichment analysis to indicate that miR-3191 was involved in the regulation of transforming growth factor beta (TGF-BETA) signal pathway in CRC. These bioinformatics results were supported by data obtained from CRC samples and experiments in vitro. The luciferase reporter assay was used to confirm that miR-3191 modulates TGF-BETA signal pathway by targeting TGFBR2. By transwell migration and invasion assays, we showed that miR-3191 promoted CRC cell migration and invasion by downregulating TGFBR2. And it may serve as a novel therapeutic strategy for treating CRC patients.


Assuntos
Movimento Celular , Neoplasias Colorretais/metabolismo , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Proteínas de Neoplasias/biossíntese , RNA Neoplásico/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo II/biossíntese , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Feminino , Células HeLa , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica , Proteínas de Neoplasias/genética , RNA Neoplásico/genética , Receptor do Fator de Crescimento Transformador beta Tipo II/genética
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