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Oxidative stress, which can be activated by a variety of environmental risk factors, has been implicated as an important pathogenic factor for inflammatory bowel disease (IBD). However, how oxidative stress drives IBD onset remains elusive. Here, we found that oxidative stress was strongly activated in inflamed tissues from both ulcerative colitis patients and Crohn's disease patients, and it caused nuclear-to-cytosolic TDP-43 transport and a reduction in the TDP-43 protein level. To investigate the function of TDP-43 in IBD, we inducibly deleted exons 2 to 3 of Tardbp (encoding Tdp-43) in mouse intestinal epithelium, which disrupted its nuclear localization and RNA-processing function. The deletion gave rise to spontaneous intestinal inflammation by inducing epithelial cell necroptosis. Suppression of the necroptotic pathway with deletion of Mlkl or the RIP1 inhibitor Nec-1 rescued colitis phenotypes. Mechanistically, disruption of nuclear TDP-43 caused excessive R-loop accumulation, which triggered DNA damage and genome instability and thereby induced PARP1 hyperactivation, leading to subsequent NAD+ depletion and ATP loss, consequently activating mitochondrion-dependent necroptosis in intestinal epithelial cells. Importantly, restoration of cellular NAD+ levels with NAD+ or NMN supplementation, as well as suppression of ALKBH7, an α-ketoglutarate dioxygenase in mitochondria, rescued TDP-43 deficiency-induced cell death and intestinal inflammation. Furthermore, TDP-43 protein levels were significantly inversely correlated with γ-H2A.X and p-MLKL levels in clinical IBD samples, suggesting the clinical relevance of TDP-43 deficiency-induced mitochondrion-dependent necroptosis. Taken together, these findings identify a unique pathogenic mechanism that links oxidative stress to intestinal inflammation and provide a potent and valid strategy for IBD intervention.
Assuntos
Doenças Inflamatórias Intestinais , Necroptose , Humanos , Animais , Camundongos , NAD/metabolismo , Estruturas R-Loop , Doenças Inflamatórias Intestinais/metabolismo , Células Epiteliais/metabolismo , Mucosa Intestinal/metabolismo , Inflamação/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Mitocôndrias/metabolismoRESUMO
Although elevated glycolysis has been widely recognized as a hallmark for highly proliferating cells like stem cells and cancer, its regulatory mechanisms are still being updated. Here, we found a previously unappreciated mechanism of mammalian target of rapamycin complex 2 (mTORC2) in regulating glycolysis in intestinal stem cell maintenance and cancer progression. mTORC2 key subunits expression levels and its kinase activity were specifically upregulated in intestinal stem cells, mouse intestinal tumors, and human colorectal cancer (CRC) tissues. Genetic ablation of its key scaffolding protein Rictor in both mouse models and cell lines revealed that mTORC2 played an important role in promoting intestinal stem cell proliferation and self-renewal. Moreover, utilizing mouse models and organoid culture, mTORC2 loss of function was shown to impair growth of gut adenoma and tumor organoids. Based on these findings, we performed RNA-seq and noticed significant metabolic reprogramming in Rictor conditional knockout mice. Among all the pathways, carbohydrate metabolism was most profoundly altered, and further studies demonstrated that mTORC2 promoted glycolysis in intestinal epithelial cells. Most importantly, we showed that a rate-limiting enzyme in regulating glycolysis, 6-phosphofructo-2-kinase (PFKFB2), was a direct target for the mTORC2-AKT signaling. PFKFB2 was phosphorylated upon mTORC2 activation, but not mTORC1, and this process was AKT-dependent. Together, this study has identified a novel mechanism underlying mTORC2 activated glycolysis, offering potential therapeutic targets for treating CRC.
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Neoplasias , Proteínas Proto-Oncogênicas c-akt , Animais , Humanos , Camundongos , Modelos Animais de Doenças , Células Epiteliais , Glicólise , Mamíferos , Alvo Mecanístico do Complexo 2 de Rapamicina , Camundongos Knockout , Fosfofrutoquinase-2 , SirolimoRESUMO
The Hippo-YAP signaling pathway plays an essential role in epithelial cells during intestinal regeneration and tumorigenesis. However, the molecular mechanism linking stromal signals to YAP-mediated intestinal regeneration and tumorigenesis is poorly defined. Here, we report a stroma-epithelium ISLR-YAP signaling axis essential for stromal cells to modulate epithelial cell growth during intestinal regeneration and tumorigenesis. Specifically, upon inflammation and in cancer, an oncogenic transcription factor ETS1 in stromal cells induces expression of a secreted protein ISLR that can inhibit Hippo signaling and activate YAP in epithelial cells. Deletion of Islr in stromal cells in mice markedly impaired intestinal regeneration and suppressed tumorigenesis in the colon. Moreover, the expression of stromal cell-specific ISLR and ETS1 significantly increased in inflamed mucosa of human IBD patients and in human colorectal adenocarcinoma, accounting for the epithelial YAP hyperactivation. Collectively, our findings provide new insights into the signaling crosstalk between stroma and epithelium during tissue regeneration and tumorigenesis.
Assuntos
Neoplasias Colorretais/metabolismo , Imunoglobulinas/genética , Imunoglobulinas/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Proteína Proto-Oncogênica c-ets-1/metabolismo , Animais , Neoplasias Colorretais/genética , Modelos Animais de Doenças , Técnicas de Inativação de Genes , Células HCT116 , Células HEK293 , Células HT29 , Via de Sinalização Hippo , Humanos , Doenças Inflamatórias Intestinais/genética , Mucosa Intestinal/metabolismo , Masculino , Camundongos , Mutação , Regiões Promotoras Genéticas , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de SinaisRESUMO
Metabolic reprogramming induced by Epstein-Barr virus (EBV) often mirrors metabolic changes observed in cancer cells. Accumulating evidence suggests that lytic reactivation is crucial in EBV-associated oncogenesis. The aim of this study was to explore the role of metabolite changes in EBV-associated malignancies and viral life cycle control. We first revealed that EBV (LMP1) accelerates the secretion of the oncometabolite D-2HG, and serum D-2HG level is a potential diagnostic biomarker for NPC. EBV (LMP1)-driven metabolite changes disrupts the homeostasis of global DNA methylation and demethylation, which have a significantly inhibitory effect on active DNA demethylation and 5hmC content. We found that loss of 5hmC indicates a poor prognosis for NPC patients, and that 5hmC modification is a restriction factor of EBV reactivation. We confirmed a novel EBV reactivation inhibitor, α-KG, which inhibits the expression of EBV lytic genes with CpG-containing ZREs and the latent-lytic switch by enhancing 5hmC modification. Our results demonstrate a novel mechanism of which metabolite abnormality driven by EBV controls the viral lytic reactivation through epigenetic modification. This study presents a potential strategy for blocking EBV reactivation, and provides potential targets for the diagnosis and therapy of NPC.
Assuntos
Metilação de DNA , Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Ativação Viral , Humanos , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/fisiologia , Carcinoma Nasofaríngeo/virologia , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/virologia , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Infecções por Vírus Epstein-Barr/virologia , Infecções por Vírus Epstein-Barr/complicações , Proteínas da Matriz Viral/metabolismo , Proteínas da Matriz Viral/genética , Epigênese Genética , Progressão da DoençaRESUMO
BACKGROUND: Gastric cancer (GC) lacks serum biomarkers with clinical diagnostic value. Multi-omics analysis is an important approach to discovering cancer biomarkers. This study aimed to identify and validate serum biomarkers for GC diagnosis by cross-analysis of proteomics and transcriptomics datasets. METHODS: A cross-omics analysis was performed to identify overlapping differentially expressed genes (DEGs) between our previous aptamer-based GC serum proteomics dataset and the GC tissue RNA-Seq dataset in The Cancer Genome Atlas (TCGA) database, followed by lasso regression and random forest analysis to select key overlapping DEGs as candidate biomarkers for GC. The mRNA levels and diagnostic performance of these candidate biomarkers were analyzed in the original and independent GC datasets to select valuable candidate biomarkers. The valuable candidate biomarkers were subjected to bioinformatics analysis to select those closely associated with the biological behaviors of GC as potential biomarkers. The clinical diagnostic value of the potential biomarkers was validated using serum samples, and their expression levels and functions in GC cells were validated using in vitro cell experiments. RESULTS: Four candidate biomarkers (ILF2, PGM2L1, CHD7, and JCHAIN) were selected. Their mRNA levels differed significantly between tumor and normal tissues and showed different diagnostic performances for GC, with areas under the receiver operating characteristic curve (AUROCs) of 0.629-0.950 in the TCGA dataset and 0.736-0.840 in the Gene Expression Omnibus (GEO) dataset. In the bioinformatics analysis, only ILF2 (interleukin enhancer-binding factor 2) gene levels were associated with immune cell infiltration, some checkpoint gene expression, chemotherapy sensitivity, and immunotherapy response. Serum levels of ILF2 were higher in GC patients than in controls, with an AUROC of 0.944 for the diagnosis of GC, and it was also detected in the supernatants of GC cells. Knockdown of ILF2 by siRNA significantly reduced the proliferation and colony formation of GC cells. Overexpression of ILF2 significantly promotes the proliferation and colony formation of gastric cancer cells. CONCLUSIONS: Trans-omics analysis of proteomics and transcriptomics is an efficient approach for discovering serum biomarkers, and ILF2 is a potential diagnostic biomarker and therapeutic target of gastric cancer.
Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Biomarcadores Tumorais/metabolismo , Perfilação da Expressão Gênica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína do Fator Nuclear 45/genéticaRESUMO
Here, we demonstrate that α-C-H and C-N bonds of unactivated secondary amides can be activated simultaneously by the copper catalyst to synthesize α-ketoamides or α-ketoesters in one step, which is a challenging and underdeveloped transformation. Using copper as a catalyst and air as an oxidant, the reaction is compatible with a broad range of acetoamides, amines, and alcohols. The preliminary mechanism studies and density functional theory calculation indicated that the reaction process may undergo first radical α-oxygenation and then transamidation with the help of the resonant six-membered N,O-chelation and molecular oxygen plays a role as an initiator to trigger the transamidation process. The combination of chelation assistance and dioxygen selective oxygenation strategy would substantially extend the modern mild synthetic amide cleavage toolbox, and we envision that this broadly applicable method will be of great interest in the biopharmaceutical industry, synthetic chemistry, and agrochemical industry.
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A new interim and connection space (ICS) and its reconstruction method are proposed. The proposed ICS,tD65A, consists of six colorimetric values or two sets of tristimulus values under CIE illuminant D65 and A respectively. In addition, a new spectral decomposition based on the tD65A ICS and the Wiener Estimation matrix MW was introduced for an improved spectral reconstruction. Accompanying the tD65A ICS, m important basis vectors for the metameric black space based on the new spectral decomposition, and a mapping matrix MP,k via a polynomial model of order k, were trained so that both the spectral and colorimetric accuracies for the reconstructed reflectance can be further enhanced. The proposed ICS and its reconstruction method can ensure exact colorimetric matches under two (real rather than synthetic) illuminants D65 and A, which is an advantage compared with other ICSs. The performance of the proposed method was tested and compared with five other ICSs using the NCS dataset and three spectral images respectively, using RMSE and GFC to measure the spectral accuracy, and using CIEDE2000 colour differences to measure the colorimetric accuracy under three types of illuminants (continuous, fluorescent, and LED). Performance test results showed the proposed methods outperform other ICSs in terms of both spectral accuracy and colorimetric measures (RMSE, GFC, and CIEDE2000 colour difference). Therefore, it is expected the proposed ICS and its reconstruction method can play an important role in spectral image compression and reproduction applications.
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BACKGROUND AND AIM: Colonic stem cells play important roles in both normal epithelial turnover and injury repair. Lgr5+ colonic stem cells are highly susceptible to DSS-induced damage. However, it is still unclear how colonic stem cells regenerate injured epithelium during colitis. Here, we explored the functions of a new population of NFATc1+ colonic stem cells in experimental colitis. METHODS: Nfatc1+ colonic stem cells were labeled using Nfatc1CreERT2 ;R26mTmG reporter mice. Immunostaining assays were used to detect Goblet cells, enteroendocrine cells, and intestinal stem/progenitor cells. We performed lineage tracing assay to investigate whether Nfatc1+ cells are real colonic stem cells using Nfatc1CreERT2 ;R26mTmG mice. The contribution of Nfatc1+ stem cells on epithelial regeneration was detected in experimental colitis induced by DSS. RESULTS: Nfatc1-reporter marked cells are enriched for +3 to +5 position in colonic crypts, and they are overlapped with Sox9+ cells and Hopx+ cells that have been identified as stem cells in small intestine. However, Nfatc1-reporter marked cells are not overlapped with Lgr5+ colonic stem cells, as well as differentiated goblet cells and enteroendocrine cells. Furthermore, Nfatc1-reporter marked cells are able to give rise to all lineages of the colonic epithelium, and they preferentially contribute to the regeneration of colonic epithelium in DSS-induced experimental colitis. CONCLUSION: Nfatc1+ cells were identified as a novel population of colonic stem cells that are primarily located at +3 to +5 position and contribute to epithelial regeneration during colitis.
Assuntos
Colite , Fatores de Transcrição NFATC , Células-Tronco , Animais , Colite/induzido quimicamente , Mucosa Intestinal/fisiologia , Camundongos , Fatores de Transcrição NFATC/genética , Regeneração , Células-Tronco/fisiologiaRESUMO
In this paper, a Riemann-Hilbert approach to a two-component modified short-pulse (mSP) system on the line with zero boundary conditions is developed. A parametric representation of the solution to the related Cauchy problem is obtained. Four nonlocal integrable reductions, namely, the real reverse space-time nonlocal focusing and defocusing mSP equations and the complex reverse space-time nonlocal focusing and defocusing mSP equations, are studied in detail. For each case, soliton solutions are presented, and, unlike their local counterparts, the nonlocal equations exhibit certain novel properties induced by the impact of nonlocality.
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BACKGROUND & AIMS: Levels of microRNA 31 (MIR31) are increased in intestinal tissues from patients with inflammatory bowel diseases and colitis-associated neoplasias. We investigated the effects of this microRNA on intestinal inflammation by studying mice with colitis. METHODS: We obtained colon biopsy samples from 82 patients with ulcerative colitis (UC), 79 patients with Crohn's disease (CD), and 34 healthy individuals (controls) at Shanghai Tenth People's Hospital. MIR31- knockout mice and mice with conditional disruption of Mir31 specifically in the intestinal epithelium (MIR31 conditional knockouts) were given dextran sulfate sodium (DSS) or 2,4,6-trinitrobenzene sulfonic acid (TNBS) to induce colitis. We performed chromatin immunoprecipitation and luciferase assays to study proteins that regulate expression of MIR31, including STAT3 and p65, in LOVO colorectal cancer cells and organoids derived from mouse colon cells. Partially hydrolyzed alpha-lactalbumin was used to generate peptosome nanoparticles, and MIR31 mimics were loaded onto their surface using electrostatic adsorption. Peptosome-MIR31 mimic particles were encapsulated into oxidized konjac glucomannan (OKGM) microspheres, which were administered by enema into the large intestines of mice with DSS-induced colitis. Intestinal tissues were collected and analyzed by histology and immunohistochemistry. RESULTS: Levels of MIR31 were increased in inflamed mucosa from patients with CD or UC, and from mice with colitis, compared with controls. STAT3 and nuclear factor-κB activated transcription of MIR31 in colorectal cancer cells and organoids in response to tumor necrosis factor and interleukin (IL)6. MIR31-knockout and conditional-knockout mice developed more severe colitis in response to DSS and TNBS, with increased immune responses, compared with control mice. MIR31 bound to 3' untranslated regions of Il17ra and Il7r messenger RNAs (RNAs) (which encode receptors for the inflammatory cytokines IL17 and IL7) and Il6st mRNA (which encodes GP130, a cytokine signaling protein). These mRNAs and proteins were greater in MIR31-knockout mice with colitis, compared with control mice; MIR31 and MIR31 mimics inhibited their expression. MIR31 also promoted epithelial regeneration by regulating the WNT and Hippo signaling pathways. OKGM peptosome-MIR31 mimic microspheres localized to colonic epithelial cells in mice with colitis; they reduced the inflammatory response, increased body weight and colon length, and promoted epithelial cell proliferation. CONCLUSIONS: MIR31, increased in colon tissues from patients with CD or UC, reduces the inflammatory response in colon epithelium of mice by preventing expression of inflammatory cytokine receptors (Il7R and Il17RA) and signaling proteins (GP130). MIR31 also regulates the WNT and Hippo signaling pathways to promote epithelial regeneration following injury. OKGM peptosome-MIR31 microspheres localize to the colon epithelium of mice to reduce features of colitis. Transcript Profiling: GSE123556.
Assuntos
Biomarcadores/metabolismo , Colite Ulcerativa/patologia , Doença de Crohn/patologia , Mucosa Intestinal/metabolismo , MicroRNAs/metabolismo , Regeneração/fisiologia , Animais , Biópsia por Agulha , Estudos de Casos e Controles , China , Modelos Animais de Doenças , Humanos , Imuno-Histoquímica , Mucosa Intestinal/patologia , Camundongos , Camundongos Knockout , Microesferas , RNA Mensageiro/metabolismo , Distribuição Aleatória , Transdução de SinaisRESUMO
Regulation of gene expression by epigenetic modifications such as DNA methylation is crucial for developmental and disease processes, including cell differentiation and cancer development. Genes repressed by DNA methylation can be derepressed by various compounds that target DNA methyltransferases, histone deacetylases, and other regulatory factors. However, some additional, unknown mechanisms that promote DNA methylation-mediated gene silencing may exist. Chemical agents that can counteract the effects of epigenetic repression that is not regulated by DNA methyltransferases or histone deacetylases therefore may be of research interest. Here, we report the results of a high-throughput screen using a 308,251-member chemical library to identify potent small molecules that derepress an EGFP reporter gene silenced by DNA methylation. Seven hit compounds were identified that did not directly target bulk DNA methylation or histone acetylation. Analyzing the effect of these compounds on endogenous gene expression, we discovered that three of these compounds (compounds LX-3, LX-4, and LX-5) selectively activate the p38 mitogen-activated protein kinase (MAPK) pathway and derepress a subset of endogenous genes repressed by DNA methylation. Selective agonists of the p38 pathway have been lacking, and our study now provides critical compounds for studying this pathway and p38 MAPK-targeted genes repressed by DNA methylation.
Assuntos
Metilação de DNA/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Acetilação , Animais , Metilases de Modificação do DNA/antagonistas & inibidores , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Proteínas de Fluorescência Verde/genética , Células HEK293 , Histona Desacetilases/metabolismo , Histonas/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos , Células NIH 3T3 , Fosforilação , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
BACKGROUND: Spinal cord astrocyte swelling is an important component to spinal cord edema and is associated with poor functional recovery as well as therapeutic resistance after spinal cord injury (SCI). High mobility group box-1 (HMGB1) is a mediator of inflammatory responses in the central nervous system and plays a critical role after SCI. Given this, we sought to identify both the role and underlying mechanisms of HMGB1 in cellular swelling and aquaporin 4 (AQP4) expression in cultured rat spinal cord astrocytes after oxygen-glucose deprivation/reoxygenation (OGD/R). METHODS: The post-natal day 1-2 Sprague-Dawley rat spinal cord astrocytes were cultured in vitro, and the OGD/R model was induced. We first investigated the effects of OGD/R on spinal cord astrocytic swelling and HMGB1 and AQP4 expression, as well as HMGB1 release. We then studied the effects of HMGB1 inhibition on cellular swelling, HMGB1 and AQP4 expression, and HMGB1 release. The roles of both toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) signaling pathway and interleukin-6 (IL-6) in reducing cellular swelling resulting from HMGB1 inhibition in spinal cord astrocytes after OGD/R were studied. Intergroup data were compared using one-way analysis of variance (ANOVA) followed by Dunnett's test. RESULTS: The OGD/R increased spinal cord astrocytic swelling and HMGB1 and AQP4 expression, as well as HMGB1 release. Inhibition of HMGB1 using either HMGB1 shRNA or ethyl pyruvate resulted in reduced cellular volume, mitochondrial and endoplasmic reticulum swelling, and lysosome number and decreased upregulation of both HMGB1 and AQP4 in spinal cord astrocytes, as well as HMGB1 release. The HMGB1 effects on spinal cord astrocytic swelling and AQP4 upregulation after OGD/R were mediated-at least in part-via activation of TLR4, myeloid differentiation primary response gene 88 (MyD88), and NF-κB. These activation effects can be repressed by TLR4 inhibition using CLI-095 or C34, or by NF-κB inhibition using BAY 11-7082. Furthermore, either OGD/R or HMGB1 inhibition resulted in changes in IL-6 release. IL-6 was also shown to mediate AQP4 expression in spinal cord astrocytes. CONCLUSIONS: HMGB1 upregulates AQP4 expression and promotes cell swelling in cultured spinal cord astrocytes after OGD/R, which is mediated through HMGB1/TLR4/MyD88/NF-κB signaling and in an IL-6-dependent manner.
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Aquaporina 4/biossíntese , Astrócitos/patologia , Proteína HMGB1/metabolismo , Traumatismos da Medula Espinal/patologia , Animais , Astrócitos/metabolismo , Interleucina-6/metabolismo , NF-kappa B/metabolismo , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Transdução de Sinais/fisiologia , Traumatismos da Medula Espinal/metabolismo , Receptor 4 Toll-Like/metabolismoRESUMO
We synthesized three 20 mer caged circular antisense oligodeoxynucleotides (R20, R20B2 and R20B4) with a photocleavable linker and an amide bond linker between two 10 mer oligodeoxynucleotides. With these caged circular antisense oligodeoxynucleotides, RNA-binding affinity and its digestion by ribonuclease H were readily photomodulated. RNA cleavage rates were upregulated ~43-, 25- and 15-fold for R20, R20B2 and R20B4, respectively, upon light activation in vitro. R20B2 and R20B4 with 2- or 4-nt gaps in the target RNA lost their ability to bind the target RNA even though a small amount of RNA digestion was still observed. The loss of binding ability indicated promising gene photoregulation through a non-enzymatic strategy. To test this strategy, three caged circular antisense oligonucleotides (PS1, PS2 and PS3) with 2'-OMe RNA and phosphorothioate modifications were synthesized to target GFP expression. Upon light activation, photomodulation of target hybridization and GFP expression in cells was successfully achieved with PS1, PS2 and PS3. These caged circular antisense oligonucleotides show promising applications of photomodulating gene expression through both ribonuclease H and non-enzyme involved antisense strategies.
Assuntos
Regulação da Expressão Gênica/efeitos da radiação , Oligonucleotídeos Antissenso/química , Fotólise , Clivagem do RNA , Proteínas de Fluorescência Verde , Células HeLa , Humanos , Cinética , Oligonucleotídeos Antissenso/metabolismo , Oligonucleotídeos Antissenso/efeitos da radiação , RNA/metabolismo , Ribonuclease HRESUMO
Balantidium coli is a cosmopolitan parasitic-opportunistic pathogen that can be found throughout the world. However, little information is available about prevalence of B. coli in pigs in China. In the present study, the prevalence of B. coli in pigs was investigated in Hunan province, subtropical China, between January 2012 and August 2014. A total of 3925 diarrheic fecal samples from nine representative administrative regions in Hunan province, subtropical China, were examined for the presence of B. coli cysts and/or trophozoites using microscopy after sedimentation with water. The overall prevalence of B. coli in pigs was 36.9 % (1450/3925). The present survey revealed high circulation of B. coli in pigs in Hunan province, subtropical China, which poses potential threats to human health. The results of the present investigation have important implications for the control of B. coli infections in pigs in Hunan province, subtropical China. To our knowledge, this is the first comprehensive report of B. coli prevalence in sows in Hunan province, subtropical China.
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Balantidíase/veterinária , Balantidium/isolamento & purificação , Fezes/microbiologia , Doenças dos Suínos/epidemiologia , Animais , Balantidíase/epidemiologia , China/epidemiologia , Feminino , Geografia , Humanos , Prevalência , Estações do Ano , Sus scrofa/microbiologia , Suínos , Temperatura , TrofozoítosRESUMO
We studied the effects of all-trans-retinoic acid (ATRA), C-phycocyanin (C-PC), or ATRA+C-PC on the growth of cervical cells (HeLa cells), cell cycle distribution, and apoptosis. The anticancer mechanism of the drug combination was revealed. MTT assay was adopted to determine the effects of C-PC and ATRA on the growth of HeLa cells. The expression quantities of cyclin-dependent kinase (CDK) 4, cyclin D1, Bcl-2, caspase-3, and CD59 were determined by in situ hybridization, immunofluorescence, immunohistochemistry staining, Western blot, and RT-PCR. TUNEL assay was adopted to determine the cellular apoptosis levels. Both C-PC and ATRA could inhibit the growth of HeLa cells, and the combination of ATRA+C-PC functioned cooperatively to induce apoptosis in HeLa cells. The dosage of ATRA was reduced when it cooperated with C-PC to reduce the toxicity. ATRA treated with C-PC could induce more cell cycle arrests than the single drug used by decrease in cyclin D1 and CDK4 expression. The combination of the two drugs could upregulate caspase-3 and downregulate the Bcl-2 gene and induce cell apoptosis. Moreover, the combination therapy has an important immunological significance in decreased expression of the CD59 protein. Singly, C-PC or ATRA could inhibit the growth of HeLa cells, and the effects of treatment were further enhanced in the combination group. In combination with C-PC, the dosage of ATRA was effectively reduced. The C-PC + ATRA combination might take effect by inhibiting the progress of the cell cycle, inducing cell apoptosis and promoting complement-mediated cytolysis.
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Antineoplásicos/administração & dosagem , Ficocianina/administração & dosagem , Tretinoína/administração & dosagem , Apoptose/efeitos dos fármacos , Antígenos CD59/análise , Caspase 3/análise , Proliferação de Células/efeitos dos fármacos , Ciclina D1/análise , Quinase 4 Dependente de Ciclina/análise , Imunofluorescência , Células HeLa , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/análiseRESUMO
Morpholino oligomers (MOs) have been widely used to knock down specific genes in zebrafish, but their constitutive activities limit their experimental applications for studying a gene with multiple functions or within a gene network. We report herein a new design and synthesis of caged circular MOs (caged cMOs) with two ends linked by a photocleavable moiety. These caged cMOs were successfully used to photomodulate ß-catenin-2 and no tail expression in zebrafish embryos.
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Regulação da Expressão Gênica , Morfolinos/química , Peixe-Zebra/genética , Animais , Embrião não Mamífero/metabolismo , Proteínas Fetais , Regulação da Expressão Gênica/efeitos da radiação , Morfolinos/síntese química , Morfolinos/efeitos da radiação , Oligodesoxirribonucleotídeos/química , Fotólise , Proteínas com Domínio T/genética , Proteínas com Domínio T/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , beta Catenina/genética , beta Catenina/metabolismoRESUMO
Ferroptosis plays important roles both in normal physiology and multiple human diseases. It is well known that selenoprotein named glutathione peroxidase 4 (GPX4) is a crucial regulator for ferroptosis. However, it remains unknown whether other selenoproteins responsible for the regulation of ferroptosis, particularly in gut diseases. In this study, it is observed that Selenoprotein I (Selenoi) prevents ferroptosis by maintaining ether lipids homeostasis. Specific deletion of Selenoi in intestinal epithelial cells induced the occurrence of ferroptosis, leading to impaired intestinal regeneration and compromised colonic tumor growth. Mechanistically, Selenoi deficiency causes a remarkable decrease in ether-linked phosphatidylethanolamine (ePE) and a marked increase in ether-linked phosphatidylcholine (ePC). The imbalance of ePE and ePC results in the upregulation of phospholipase A2, group IIA (Pla2g2a) and group V (Pla2g5), as well as arachidonate-15-lipoxygenase (Alox15), which give rise to excessive lipid peroxidation. Knockdown of PLA2G2A, PLA2G5, or ALOX15 can reverse the ferroptosis phenotypes, suggesting that they are downstream effectors of SELENOI. Strikingly, GPX4 overexpression cannot rescue the ferroptosis phenotypes of SELENOI-knockdown cells, while SELENOI overexpression can partially rescue GPX4-knockdown-induced ferroptosis. It suggests that SELENOI prevents ferroptosis independent of GPX4. Taken together, these findings strongly support the notion that SELENOI functions as a novel suppressor of ferroptosis during colitis and colon tumorigenesis.
Assuntos
Colite , Neoplasias Colorretais , Ferroptose , Selenoproteínas , Ferroptose/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Camundongos , Animais , Selenoproteínas/metabolismo , Selenoproteínas/genética , Colite/metabolismo , Colite/genética , Humanos , Modelos Animais de Doenças , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Transdução de Sinais/genéticaRESUMO
Purpose: The differential diagnosis of atypical hepatocellular carcinoma (aHCC) and atypical benign focal hepatic lesions (aBFHL) usually depends on pathology. This study aimed to develop non-invasive approaches based on conventional blood indicators for the differential diagnosis of aHCC and aBFHL. Patients and Methods: Hospitalized patients with pathologically confirmed focal hepatic lesions and their clinical data were retrospectively collected, in which patients with HCC with serum alpha-fetoprotein (AFP) levels of ≤200 ng/mL and atypical imaging features were designated as the aHCC group (n = 224), and patients with benign focal hepatic lesions without typical imaging features were designated as the aBFHL group (n = 178). The performance of indexes (both previously reported and newly constructed) derived from conventional blood indicators by four mathematical operations in distinguishing aHCC and aBFHL was evaluated using the receiver operating characteristic (ROC) curve and diagnostic validity metrics. Results: Among ten previously reported derived indexes related to HCC, the index GPR, the ratio of γ-glutamyltransferase (GGT) to platelet (PLT), showed the best performance in distinguishing aHCC from aBFHL with the area under ROC curve (AUROC) of 0.853 (95% CI 0.814-0.892), but the other indexes were of little value (AUROCs from 0.531 to 0.700). A new derived index, sAGP [(standardized AFP + standardized GGT)/standardized PLT], was developed and exhibited AUROCs of 0.905, 0.894, 0.891, 0.925, and 0.862 in differentiating overall, BCLC stage 0/A, TNM stage I, small, and AFP-negative aHCC from aBFHL, respectively. Conclusion: The sAGP index is an efficient, simple, and practical metric for the non-invasive differentiation of aHCC from aBFHL.
RESUMO
RNA N6-methyladenosine (m6A), as the most abundant modification of messenger RNA, can modulate insect behaviors, but its specific roles in aggregation behaviors remain unexplored. Here, we conducted a comprehensive molecular and physiological characterization of the individual components of the methyltransferase and demethylase in the migratory locust Locusta migratoria. Our results demonstrated that METTL3, METTL14 and ALKBH5 were dominantly expressed in the brain and exhibited remarkable responses to crowding or isolation. The individual knockdown of methyltransferases (i.e., METTL3 and METTL14) promoted locust movement and conspecific attraction, whereas ALKBH5 knockdown induced a behavioral shift toward the solitary phase. Furthermore, global transcriptome profiles revealed that m6A modification could regulate the orchestration of gene expression to fine tune the behavioral aggregation of locusts. In summary, our in vivo characterization of the m6A functions in migratory locusts clearly demonstrated the crucial roles of the m6A pathway in effectively modulating aggregation behaviors.
Assuntos
Adenosina , Locusta migratoria , Metiltransferases , Animais , Adenosina/metabolismo , Adenosina/análogos & derivados , Locusta migratoria/genética , Locusta migratoria/fisiologia , Locusta migratoria/metabolismo , Metiltransferases/metabolismo , Metiltransferases/genética , Comportamento Animal/fisiologia , Encéfalo/metabolismo , Encéfalo/fisiologia , Transcriptoma , Homólogo AlkB 5 da RNA Desmetilase/metabolismo , Homólogo AlkB 5 da RNA Desmetilase/genética , Regulação da Expressão Gênica , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Gafanhotos/genética , Gafanhotos/fisiologia , Gafanhotos/metabolismoRESUMO
A coumarin-based fluorescence chemoprobe was developed and evaluated for the selective and sensitive detection of hydrogen sulfide in degassed PBS buffers and fetal bovine serum. Fluorescence detection of hydrogen sulfide in living cells was also successfully achieved using two-photon confocal fluorescence imaging. Further in situ visualization of endogenous H(2)S was realized in cardiac tissues of normal rats and atherosclerosis (AS) rats.