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Antimony (Sb) poses a significant ecological threat. This study combines biochemical, pathological, transcriptome, and metabolome analyses to assess the short-term (14-day) toxic impact of two Sb levels (25â¯mg/kg and 125â¯mg/kg) on earthworms (Eisenia fetida). Higher Sb concentration caused severe intestinal damage, elevated metallothionein (MT) levels, and reduced antioxidant capacity. Metabolome analysis identifies 404 and 1698 significantly differential metabolites in the two groups. Metabolites such as S(-)-cathinone, N-phenyl-1-naphthylamine, serotonin, 4-hydroxymandelonitrile, and 5-fluoropentylindole contributed to the metabolic responses to Sb stress. Transcriptome analysis shows increased chitin synthesis as a protective response, impacting amino sugar and nucleotide sugar metabolism for cell wall synthesis and damage repair. Integrated analysis indicated that 5 metabolite-gene pairs were found in two Sb levels and 11 enriched pathways were related to signal transduction, carbohydrate metabolism, immune system, amino acid metabolism, digestive system, and nervous system. Therefore, the integration of multiomics approaches enhanced our comprehension of the molecular mechanisms underlying the toxicity of Sb in E. fetida.
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Ten-eleven translocation 1 (TET1) is a methylcytosine dioxygenase involved in active DNA demethylation. In our previous study, we demonstrated that TET1 reprogrammed the ovarian cancer epigenome, increased stem properties, and activated various regulatory networks, including metabolic networks. However, the role of TET1 in cancer metabolism remains poorly understood. Herein, we uncovered a demethylated metabolic gene network, especially oxidative phosphorylation (OXPHOS). Contrary to the concept of the Warburg effect in cancer cells, TET1 increased energy production mainly using OXPHOS rather than using glycolysis. Notably, TET1 increased the mitochondrial mass and DNA copy number. TET1 also activated mitochondrial biogenesis genes and adenosine triphosphate production. However, the reactive oxygen species levels were surprisingly decreased. In addition, TET1 increased the basal and maximal respiratory capacities. In an analysis of tricarboxylic acid cycle metabolites, TET1 increased the levels of α-ketoglutarate, which is a coenzyme of TET1 dioxygenase and may provide a positive feedback loop to modify the epigenomic landscape. TET1 also increased the mitochondrial complex I activity. Moreover, the mitochondrial complex I inhibitor, which had synergistic effects with the casein kinase 2 inhibitor, affected ovarian cancer growth. Altogether, TET1-reprogrammed ovarian cancer stem cells shifted the energy source to OXPHOS, which suggested that metabolic intervention might be a novel strategy for ovarian cancer treatment.
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Antimony (Sb) is known for its severe and extensive toxicity, and earthworms are considered important indicator organisms in soil ecosystems. Therefore, the present study investigated the mechanism of toxicity of the Sb at different concentrations (50, 200 mg/kg) on earthworms using biochemical indicators, pathological sections, as well as metabolomics and transcriptomics analyses. The results showed that as the exposure concentration increased, both the antioxidant system of earthworms, extent of intestinal damage, and their metabolomic characteristics were significantly enhanced. In the 50 and 200 mg/kg Sb treatment group, 30 and 177 significant differentially changed metabolites (DCMs) were identified, respectively, with the most DCMs being down- and up-regulated, respectively. Metabolomics analysis showed that the contents of dl-tryptophan, glutamic acid, glycine, isoleucine, l-methionine, involved in the protein digestion and absorption as well as aminoacyl-tRNA biosynthesis were significantly up-regulated under the 200 mg/kg treatment. At the transcriptional level, Sb mainly affected the immune system, nervous system, amino acid metabolism, endocrine system, and carbohydrate metabolism in earthworms. The integration of transcriptomic and metabolomic data indicated that high doses of Sb regulated the metabolites and genes related to the oxidative phosphorylation pathway in earthworms. Overall, these results revealed global responses beyond the scope of conventional toxicity endpoints and facilitated a more in-depth and comprehensive assessment of the toxic effects of Sb.
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Antimonio , Metabolismo Energético , Metaboloma , Oligoquetos , Contaminantes del Suelo , Transcriptoma , Animales , Oligoquetos/efectos de los fármacos , Oligoquetos/metabolismo , Oligoquetos/genética , Metaboloma/efectos de los fármacos , Transcriptoma/efectos de los fármacos , Antimonio/toxicidad , Metabolismo Energético/efectos de los fármacos , Contaminantes del Suelo/toxicidad , MetabolómicaRESUMEN
OBJECTIVES: To investigate the potential protective effects of evolocumab, a proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor, on ischemic stroke and its underlying mechanisms. MATERIALS AND METHODS: We established a mouse model with distal middle cerebral artery occlusion. We evaluated the therapeutic effects through neurological function and infarct size, while the underlying mechanisms were elucidated using western blotting and real-time polymerase chain reaction. RESULTS: Evolocumab improved neurological recovery, reduced the infarct volume, suppressed the activation of Toll-like receptor (TLR) 4 and nuclear factor-kappa B (NF-κB), and attenuated the increased levels of IL-1ß and TNF-α after cerebral ischemia. CONCLUSION: Evolocumab protects against cerebral ischemic injury by inhibiting inflammation. Therefore, the TLR4/NF-кB pathway may represent a major mechanism in ischemic stroke.
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Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Ratones , Animales , Proproteína Convertasa 9/metabolismo , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/metabolismo , FN-kappa B/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Infarto de la Arteria Cerebral Media/metabolismo , Subtilisinas/uso terapéuticoRESUMEN
Poly(ethylene terephthalate) (PET) is one of the most widely used synthetic polyesters, however, its extensive use creates a long-term environmental burden. Unlike traditional recycling methods, biodegradation is a sustainable strategy. The emergence of PETase from Ideonella sakaiensis 201-F6 (IsPETase) has brought great potential for the industrialization of degradable PET. In this work, models of enzyme-substrate complexes with different degrees of polymerization were established to study the binding mode using molecular dynamics simulation. We found that the whole binding site can be further subdivided into three parts, including head, middle and tail binding regions. Most importantly, the presence of the middle region formed by both ends of Ser93 and Ser236 provides a potential possibility for the binding of substrates with different chain lengths, and exerts the self-regulation ability of enzymes to accommodate substrates. Meanwhile, the 'pocket bottom' Arg280 in the tail region echoes the 'pocket mouth' Trp185 in the head region, defining the substrate binding region. This work reveals the self-regulation of IsPETase, as well as the key residues for the substrate binding. The solution to these problems enables us to better understand the function of enzymes and design high-performance degradation enzymes, which is of great significance for industrial application research.
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Hidrolasas , Autocontrol , Hidrolasas/química , Polimerizacion , Dominios Proteicos , Biodegradación Ambiental , Tereftalatos Polietilenos/químicaRESUMEN
BACKGROUND: Our previous research revealed that inflammation plays an important role in the pathophysiology of cerebral ischemia. The function of the NOD-like receptor protein 3 (NLRP3) inflammasome is to activate the inflammatory process. Recent findings suggest that reactive oxygen species (ROS) are essential secondary messengers that activate the NLRP3 inflammasome. Hydrogen-rich saline (HS) has attracted attention for its anti-inflammatory properties. However, the protective effect and possible mechanism of HSin brain ischemia have not been well elucidated. METHODS: To test the therapeutic effect of HS, we established a mouse model of distal middle cerebral artery occlusion (dMCAO) and an in vitro model of BV2 cells induced by lipopolysaccharide (LPS). The ROS scavenger N-acetylcysteine (NAC) was used to investigate the underlying mechanisms of HS. RESULTS: HS significantly improved neurological function, reduced infarct volume, and increased cerebral blood flow in a dMCAO mouse model. ROS, NLRP3, Caspase-1, and IL-1ß expression increased after cerebral ischemia, and this was reversed by HS treatment. In BV2 cells, the application of NAC further demonstrated that HS could effectively inhibit the expression of the ROS-activated NLRP3 inflammasome. CONCLUSIONS: HS, as a novel therapeutic option, could exert protect the brain by inhibiting the activation of the ROS-NLRP3 signaling pathway after cerebral ischemia.
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Window of implantation (WOI) genes have been comprehensively identified at the single cell level. DNA methylation changes in cervical secretions are associated with in vitro fertilization embryo transfer (IVF-ET) outcomes. Using a machine learning (ML) approach, we aimed to determine which methylation changes in WOI genes from cervical secretions best predict ongoing pregnancy during embryo transfer. A total of 2708 promoter probes were extracted from mid-secretory phase cervical secretion methylomic profiles for 158 WOI genes, and 152 differentially methylated probes (DMPs) were selected. Fifteen DMPs in 14 genes (BMP2, CTSA, DEFB1, GRN, MTF1, SERPINE1, SERPINE2, SFRP1, STAT3, TAGLN2, TCF4, THBS1, ZBTB20, ZNF292) were identified as the most relevant to ongoing pregnancy status. These 15 DMPs yielded accuracy rates of 83.53%, 85.26%, 85.78%, and 76.44%, and areas under the receiver operating characteristic curves (AUCs) of 0.90, 0.91, 0.89, and 0.86 for prediction by random forest (RF), naïve Bayes (NB), support vector machine (SVM), and k-nearest neighbors (KNN), respectively. SERPINE1, SERPINE2, and TAGLN2 maintained their methylation difference trends in an independent set of cervical secretion samples, resulting in accuracy rates of 71.46%, 80.06%, 80.72%, and 80.68%, and AUCs of 0.79, 0.84, 0.83, and 0.82 for prediction by RF, NB, SVM, and KNN, respectively. Our findings demonstrate that methylation changes in WOI genes detected noninvasively from cervical secretions are potential markers for predicting IVF-ET outcomes. Further studies of cervical secretion of DNA methylation markers may provide a novel approach for precision embryo transfer.
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Infertilidad Femenina , beta-Defensinas , Femenino , Embarazo , Humanos , Metilación de ADN , Teorema de Bayes , Serpina E2/genética , Infertilidad Femenina/metabolismo , Endometrio/metabolismo , Implantación del Embrión/genética , Marcadores Genéticos , Fertilización In Vitro/métodos , beta-Defensinas/metabolismo , Proteínas Portadoras/metabolismo , Proteínas del Tejido Nervioso/metabolismoRESUMEN
In this study, we assessed the acute and chronic toxic effects of Sb (III) and Sb (V) on Eisenia fetida (Savingy) (E. fetida) by applying the filter paper contact method, aged soil treatment, and avoidance test experiment. In the acute filter paper contact test, the LC50 values for Sb (III) were 2581 mg/L (24 h), 1427 mg/L (48 h), and 666 mg/L (72 h), which were lower than Sb (V). In the chronic aged soil exposure experiment, when the Sb (III)-contaminated soil was aged 10 d, 30 d, and 60 d after exposure for 7 d, the LC50 value of E. fetida was 370, 613, and >4800 mg/kg, respectively. Compared to Sb (V) spiked soils aged only for 10 d, the concentrations causing 50% mortality significantly increased by 7.17-fold after 14 days of exposure in soil aged for 60 d. The results show that Sb (III) and Sb (V) could cause death and directly affect the avoidance behavior of E. fetida; yet, the toxicity of Sb (III) was higher than that of Sb (V). Consistent with the decrease in water-soluble Sb, the toxicity of Sb to E. fetida was greatly reduced with time. Therefore, in order to avoid overestimating the ecological risk of Sb with varying oxidative states, it is important to consider the forms and bioavailability of Sb. This study accumulated and supplemented the toxicity data, and provided a more comprehensive basis for the ecological risk assessment of Sb.
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The causes of implantation failure remain a black box in reproductive medicine. The exact mechanism behind the regulation of endometrial receptivity is still unknown. Epigenetic modifications influence gene expression patterns and may alter the receptivity of human endometrium. Cervical secretions contain endometrial genetic material, which can be used as an indicator of the endometrial condition. This study evaluates the association between the cervical secretion gene methylation profile and pregnancy outcome in a frozen-thawed embryonic transfer (FET) cycle. Cervical secretions were collected from women who entered the FET cycle with a blastocyst transfer (36 pregnant and 36 non-pregnant women). The DNA methylation profiles of six candidate genes selected from the literature review were measured by quantitative methylation-specific PCR (qMSP). Bioinformatic analysis of six selected candidate genes showed significant differences in DNA methylation between receptive and pre-receptive endometrium. All candidate genes showed different degrees of correlation with the pregnancy outcomes in the logistic regression model. A machine learning approach showed that the combination of candidate genes' DNA methylation profiles could differentiate pregnant from non-pregnant samples with an accuracy as high as 86.67% and an AUC of 0.81. This study demonstrated the association between cervical secretion methylation profiles and pregnancy outcomes in an FET cycle and provides a basis for potential clinical application as a non-invasive method for implantation prediction.
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Transferencia de Embrión , Resultado del Embarazo , Embarazo , Femenino , Humanos , Transferencia de Embrión/métodos , Implantación del Embrión/genética , Índice de Embarazo , Endometrio/metabolismo , Metilación de ADN , Estudios Retrospectivos , Criopreservación/métodosRESUMEN
BACKGROUND: We describe a DNA methylation assay, named MPap test, using cervical scraping as an alternative technique for endometrial cancer detection. METHODS: A multicenter hospital-based, two-stage validation study was conducted to validate the cancer detection performance of the MPap test. The MPap value was determined from the DNA methylation status of two genes (BHLHE22, CDO1) and combined with two other clinical variables (age, BMI). The cutoff threshold of the MPap value was established in stage 1 and validated in stage 2. A total of 592 women with abnormal uterine bleeding were enrolled from five medical centers throughout Taiwan. RESULTS: In stage 1, the sensitivity, specificity, and positive and negative predictive values of the MPap test for detecting endometrial cancer were 92.9%, 71.5%, 39.8%, and 98.0%, respectively. These values were validated in stage 2, being 92.5%, 73.8%, 40.2%, and 98.1%. Moreover, MPap outperformed transvaginal ultrasound in sensitivity and negative predictive values for detecting endometrial cancer. When we applied the algorithm for triage of endometrial cancer detection by MPap in the Taiwan National Health Insurance dataset, we found that it may reduce invasive procedures by 69~73%. CONCLUSIONS: MPap may provide a feasible alternative for endometrial cancer detection and can be considered as a triage test to reduce unnecessary invasive procedures.
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Endometrial cancer (EC) rates are rising annually. Additional prediction markers need to be evaluated because only 10-20% of EC cases show an objective response to immune-checkpoint inhibitors (ICIs). Our previous methylomic study found that BHLHE22 is hypermethylated in EC tissues and can be detected using a Pap-smear sample. BHLHE22, a basic helix loop helix transcription factor family member, is known as a transcriptional repressor and is involved in cell differentiation. However, the role of BHLHE22 in EC remains poorly understood. Herein, we analyzed BHLHE22 expression in 54 paired cancer and normal endometrial tissue samples, and confirmed with databases (TCGA, GTEx, and human protein atlas). We found that BHLHE22 protein expression was significantly downregulated in EC compared with normal endometrium. High BHLHE22 expression was associated with microsatellite-instable subtype, endometrioid type, grade, and age. It showed a significant favorable survival. BHLHE22 overexpression inhibited the proliferation and migration of EC cells. Functional enrichment analysis showed that BHLHE22 was significantly associated with immune-related pathways. Furthermore, BHLHE22 was positively correlated with proinflammatory leukocyte infiltration and expression of chemokine genes in EC. In conclusion, BHLHE22 regulates immune-related pathways and modulates the immune microenvironment of EC.
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Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Neoplasias Endometriales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/biosíntesis , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Quimiocinas/metabolismo , Neoplasias Endometriales/metabolismo , Endometrio/metabolismo , Femenino , Humanos , Microambiente TumoralRESUMEN
Adenomyosis is linked to dysmenorrhea and infertility. The pathogenesis of adenomyosis remains unclear, and little is known of the genetic and epigenetic changes in the eutopic endometrium in adenomyosis, which may predispose patients to the invasion and migration of endometrial tissues into the myometrium. Transcriptome studies have identified genes related to various cell behaviors but no targets for therapeutic intervention. The epigenetics of the eutopic endometrium in adenomyosis have rarely been investigated. Endometrial tissue was obtained from premenopausal women with (n = 32) or without adenomyosis (n = 17) who underwent hysterectomy aged 34-57 years at a tertiary hospital. The methylome and transcriptome were assessed by using a Methylation 450 K BeadChip array and Affymetrix expression microarray. Protein expression was examined by immunohistochemistry. Differential methylation analysis revealed 53 lowly methylated genes and 176 highly methylated genes with consistent gene expression in adenomyosis, including three genes encoding potassium ion channels. High expression of KCNK9 in the eutopic and ectopic endometria in patients with adenomyosis but not in normal controls was observed. Hormone-free, antibody-based KCNK9 targeting is a potential therapeutic strategy for adenomyosis-related dysmenorrhea, menorrhagia, and infertility.
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Adenomiosis , Endometriosis , Infertilidad , Canales de Potasio de Dominio Poro en Tándem , Adenomiosis/genética , Adenomiosis/metabolismo , Adenomiosis/patología , Dismenorrea/genética , Endometriosis/patología , Endometrio/metabolismo , Epigenómica , Femenino , Humanos , Infertilidad/metabolismo , Canales de Potasio/metabolismo , Canales de Potasio de Dominio Poro en Tándem/metabolismoRESUMEN
Overcoming drug resistance is an inevitable challenge to the success of cancer treatment. Recently, in ovarian cancer, a highly chemoresistant tumor, we demonstrated an important role of shear stress in stem-like phenotype and chemoresistance using a three-dimensional microfluidic device, which most closely mimics tumor behavior. Here, we examined a new mechanosensitive microRNA-miR-199a-3p. Unlike most key microRNA biogenesis in static conditions, we found that Dicer, Drosha, and Exportin 5 were not involved in regulating miR-199a-3p under ascitic fluid shear stress (0.02 dynes/cm2). We further showed that hepatocyte growth factor (HGF), but not other ascitic cytokines/growth factors such as epidermal growth factor and tumor necrosis factor α or hypoxia, could transcriptionally downregulate miR-199a-3p through its primary transcript miR-199a-1 and not miR-199a-2. Shear stress in the presence of HGF resulted in a concerted effect via a specific c-Met/PI3K/Akt signaling axis through a positive feedback loop, thereby driving cancer stemness and drug resistance. We also showed that miR-199a-3p expression was inversely correlated with enhanced drug resistance properties in chemoresistant ovarian cancer lines. Patients with low miR-199a-3p expression were more resistant to platinum with a significantly poor prognosis. miR-199a-3p mimic significantly suppressed ovarian tumor metastasis and its co-targeting in combination with cisplatin or paclitaxel further decreased the peritoneal dissemination of ovarian cancer in mice. These findings unravel how biophysical and biochemical cues regulate miR-199a-3p and is important in chemoresistance. miR-199a-3p mimics may serve as a novel targeted therapy for effective chemosensitization.
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MicroARNs , Neoplasias Ováricas , Animales , Líquido Ascítico/metabolismo , Líquido Ascítico/patología , Línea Celular Tumoral , Proliferación Celular/genética , Resistencia a Antineoplásicos/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Factor de Crecimiento de Hepatocito/genética , Factor de Crecimiento de Hepatocito/metabolismo , Humanos , Ratones , MicroARNs/metabolismo , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-met/genética , Proteínas Proto-Oncogénicas c-met/metabolismo , Transducción de Señal/genéticaRESUMEN
OBJECTIVE: To study whether the methylation status of cervical secretions can reflect the ability of the endometrium to allow embryo implantation. DESIGN: Case-control study. SETTING: In vitro fertilization centers. PATIENT(S): Women undergoing embryo transfer cycles, in which at least 1 good-quality embryo was transferred. INTERVENTION(S): Collection of cervical secretions during the procedure of embryo transfer. MAIN OUTCOME MEASURE(S): Methylation profiles of cervical secretions in relation to pregnancy outcomes. RESULT(S): Genome-wide methylation profiles differ between cervical secretions from pregnancy and nonpregnancy cycles. Clustering analysis on the basis of the top 2,000 differentially methylated probes of cervical secretions from 28 pregnancy and 29 nonpregnancy cycles correctly categorized 86.0% of the samples in terms of conceptional status, which was verified in selected genes by quantitative methylation-specific polymerase chain reaction and validated in another independent sample set. The combination of selected genes was estimated to predict pregnancy outcomes with a maximal area under the receiver operating characteristic curve of 0.83. CONCLUSION(S): The methylation profiles of cervical secretions were associated with pregnancy outcomes in embryo transfer cycles. Although not clinically useful at present, deoxyribonucleic acid methylation in cervical secretions may shed new light on the less invasive assessment of endometrial receptivity.
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Transferencia de Embrión , Resultado del Embarazo , Estudios de Casos y Controles , ADN , Transferencia de Embrión/métodos , Femenino , Humanos , Metilación , EmbarazoRESUMEN
Intraperitoneal metastasis is a challenging clinical scenario in epithelial ovarian cancer (EOC). As they are distinct from hematogenous metastasizing tumors, epithelial ovarian cancer cells primarily disseminate within the peritoneal cavity to form superficially invasive carcinomas. Unfavorable pharmacokinetics for peritoneal tumors and gut toxicity collectively lead to a narrow therapeutic window and therefore limit the opportunities for a favorable clinical outcome. New insights into tumor metastasis in the peritoneal microenvironment are keenly awaited to develop new therapeutic strategies. Epithelial ovarian cancer stem cell (OCSC) seeding is considered to be a critical component of the peritoneal spread. Using a unique and stepwise process of the OCSC differentiation model may provide insight into the intraperitoneal metastasis. The transcriptome and epigenome of OCSC differentiation were characterized by expression array and MethylCap-Seq. The TCGA, AOCS, and KM-Plotter databases were used to evaluate the association between survival outcomes and the methylation/expression levels of candidate genes in the EOC datasets. The STRING database was used to investigate the protein-protein interaction (PPI) for candidates and their associated genes. The infiltration level of immune cells in EOC patients and the association between clinical outcome and OCSCs differentiation genes were estimated using the TIDE and TIME2.0 algorithms. We established an EOC differentiation model using OCSCs. After an integrated transcriptomics and methylomics analysis of OCSCs differentiation, we revealed that the genes associated with earlier OCSC differentiation were better able to reflect the patient's outcome. The OCSC differentiation genes were involved in regulating metabolism shift and the suppressive immune microenvironment. High GPD1 expression with high pro-tumorigenic immune cells (M2 macrophage, and cancer associated fibroblast) had worst survival. Moreover, we developed a methylation signature, constituted by GNPDA1, GPD1, GRASP, HOXC11, and MSLN, that may be useful for prognostic prediction in EOC. Our results revealed a novel role of epigenetic plasticity OCSC differentiation and suggested metabolic and immune intervention as a new therapeutic strategy.
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Epigenómica , Neoplasias Ováricas , Biomarcadores de Tumor/genética , Carcinoma Epitelial de Ovario/patología , Diferenciación Celular/genética , Femenino , Proteínas de Homeodominio , Humanos , Neoplasias Ováricas/patología , Microambiente Tumoral/genéticaRESUMEN
Due to deadly toxicity and high environmental stability of the nerve agent VX, an efficient decontamination approach is desperately needed in tackling its severe threat to human security. The enzymatic destruction of nerve agents has been generally considered as one of the most effective ways, and here the hydrolysis of VX by phosphotriesterase (PTE) was investigated by extensive QM/MM and MM MD simulations. The hydrolytic cleavage of P-S by PTE is a two-step process with the free energy spans of 15.8 and 26.0 kcal mol-1 for the RP- and SP-enantiomer VX, respectively, and such remarkable stereospecificity of VX enantiomers in the enzymatic degradation is attributed to their conformational compatibility with the active pocket. The structurally less adaptive SP-enantiomer allows one additional water molecule to enter the binuclear zinc center and remarkably facilitates the release of the degraded product. Overall, the rate-limiting steps in the enzymatic degradation of VX by PTE involve the degraded product release of the RP-enantiomer and the enzymatic P-S cleavage of the SP-enantiomer. Further computational analysis on the mutation of selected residues also revealed that H257Y, H257D, H254Q-H257F, and L7ep-3a variants allow more water molecules to enter the active site, which improves the catalytic efficiency of PTE, as observed experimentally. The present work provides mechanistic insights into the stereoselective hydrolysis of VX by PTE and the activity manipulation through the active-site accessibility of water molecules, which can be used for the enzyme engineering to defeat chemical warfare agents.
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Sustancias para la Guerra Química , Agentes Nerviosos , Hidrolasas de Triéster Fosfórico , Dominio Catalítico , Sustancias para la Guerra Química/química , Sustancias para la Guerra Química/metabolismo , Sustancias para la Guerra Química/toxicidad , Descontaminación , Humanos , Hidrólisis , Compuestos Organotiofosforados , Hidrolasas de Triéster Fosfórico/química , Hidrolasas de Triéster Fosfórico/genética , Hidrolasas de Triéster Fosfórico/metabolismo , AguaRESUMEN
It was recently shown that pyroptosis, an inflammatory form of programmed cell death, is critically involved in the pathogenesis of ischemic stroke. Liraglutide (Lg) is a novel long-acting analog of glucagon-like peptide-1 that has potential protective effects against stroke. However, the relationship between Lg and pyroptosis in the brain is not well defined. In this study, we found that injection of Lg significantly improved the recovery of motor function, increased cerebral blood flow and ameliorated cerebral damage in a mouse model of focal cerebral cortical ischemia. Our results revealed that Lg treatment significantly reduced the levels of NLRP3, Caspase1, IL-1ß and the pore-forming protein gasdermin D in microglial cells in vitro, suggesting that the neuroprotective effect of Lg may be achieved through the inhibition of pyroptosis. Furthermore, by using a specific inhibitor of NOD-like receptor protein 3 (NLRP3), we confirmed that the antipyroptotic mechanism of Lg may be mediated by NLRP3 in vivo. Our present study unveils a novel neuroprotective mechanism through which Lg alleviates ischemia by exerting NLRP3-dependent antipyroptotic effects.
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Isquemia Encefálica , Accidente Cerebrovascular , Animales , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/metabolismo , Inflamasomas/metabolismo , Liraglutida/farmacología , Liraglutida/uso terapéutico , Ratones , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Piroptosis , Accidente Cerebrovascular/metabolismoRESUMEN
BACKGROUND: Leiomyosarcoma (LMS), the most common soft tissue sarcoma, exhibits heterogeneous and complex genetic karyotypes with severe chromosomal instability and rearrangement and poor prognosis. METHODS: Clinical variables associated with NKX6-1 were obtained from The Cancer Genome Atlas (TCGA). NKX6-1 mRNA expression was examined in 49 human uterine tissues. The in vitro effects of NXK6-1 in LMS cells were determined by reverse transcriptase PCR, western blotting, colony formation, spheroid formation, and cell viability assays. In vivo tumor growth was evaluated in nude mice. RESULTS: Using The Cancer Genome Atlas (TCGA) and human uterine tissue datasets, we observed that NKX6-1 expression was associated with poor prognosis and malignant potential in LMS. NKX6-1 enhanced in vitro tumor cell aggressiveness via upregulation of cell proliferation and anchorage-independent growth and promoted in vivo tumor growth. Moreover, overexpression and knockdown of NKX6-1 were associated with upregulation and downregulation, respectively, of stem cell transcription factors, including KLF8, MYC, and CD49F, and affected sphere formation, chemoresistance, NOTCH signaling and Sonic hedgehog (SHH) pathways in human sarcoma cells. Importantly, treatment with an SHH inhibitor (RU-SKI 43) but not a NOTCH inhibitor (DAPT) reduced cell survival in NKX6-1-expressing cancer cells, indicating that an SHH inhibitor could be useful in treating LMS. Finally, using the TCGA dataset, we demonstrated that LMS patients with high expression of NKX6-1 and HHAT, an SHH pathway acyltransferase, had poorer survival outcomes compared to those without. CONCLUSIONS: Our findings indicate that NKX6-1 and HHAT play critical roles in the pathogenesis of LMS and could be promising diagnostic and therapeutic targets for LMS patients.
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Proteínas Hedgehog/genética , Proteínas de Homeodominio/genética , Leiomiosarcoma/metabolismo , Células Madre Neoplásicas/metabolismo , Transducción de Señal , Animales , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Proteínas Hedgehog/metabolismo , Proteínas de Homeodominio/metabolismo , Ratones , Ratones DesnudosRESUMEN
BACKGROUND: Upper-extremity hemiplegia after stroke remains a significant clinical problem. The supplementary motor area (SMA) is vital to the motor recovery outcomes of chronic stroke patients. Therefore, rebuilding the descending motor tract from the SMA to the paralyzed limb is a potential approach to restoring arm motor function after stroke. Paired associative stimulation (PAS), which is based on Hebbian theory, is a potential method for reconstructing the connections in the impaired motor neural circuits. The study described in this protocol aims to assess the effects of cortico-peripheral Hebbian-type stimulation (HTS), involving PAS, for neural circuit reconstruction to rescue the paralyzed arm after stroke. METHODS: The study is a 4-month double-blind randomized sham-controlled clinical trial. We will recruit 90 post-stroke individuals with mild to moderate upper limb paralysis. Based on a 1:1 ratio, the participants will be randomly assigned to the HTS and sham groups. Each participant will undergo 5-week HTS or sham stimulation. Assessments will be conducted at baseline, immediately after the 5-week treatment, and at a 3-month follow-up. The primary outcome will be the Wolf Motor Function Test (WMFT). The secondary outcomes will be Fugl-Meyer Assessment for Upper Extremity (FMA-UE), Functional Independence Measure (FIM), and functional near-infrared spectroscopy (fNIRS) parameters. The adverse events will be recorded throughout the study. DISCUSSION: Upper-limb paralysis in stroke patients is due to neural circuit disruption, so the reconstruction of effective motor circuits is a promising treatment approach. Based on its anatomical structure and function, the SMA is thought to compensate for motor dysfunction after focal brain injury at the cortical level. Our well-designed randomized controlled trial will allow us to analyze the clinical efficacy of this novel Hebbian theory-based neuromodulation strategy regarding promoting the connection between the cortex and peripheral limb. The results may have significance for the development and implementation of effective neurorehabilitation treatments. CLINICAL TRIAL REGISTRATION: [www.ClinicalTrials.gov], identifier [ChiCTR2000039949].
Asunto(s)
Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Brazo , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Recuperación de la Función/fisiología , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/terapia , Rehabilitación de Accidente Cerebrovascular/métodos , Extremidad SuperiorRESUMEN
BACKGROUND: Patients with ovarian clear cell carcinoma (OCCC) have a poor prognosis because they show low sensitivity to platinum-based chemotherapy. New treatments for refractory OCCC are urgently needed. CASE PRESENTATION: We present a patient with refractory OCCC in whom conventional chemotherapy failed. Cachexia was induced by the disseminating recurrent tumors. Tumor tissue staining and genomic analysis revealed PD-L1 negativity, a low tumor burden, stable microsatellite instability, and two mutations in ARID1A. The patient was administered pembrolizumab combined with bevacizumab triweekly. Her serum CA-125 level decreased dramatically after the first cycle. A computerized tomography scan showed marked regression of the recurrent masses after 3 cycles, and the patient reached complete remission after 9 cycles. She showed good recovery from cachexia. We observed no marked side effects except for mild polyarthritis of the small joints. CONCLUSIONS: The therapeutic effect of checkpoint inhibitors combined with angiogenesis inhibitors is very promising in our patient with OCCC. Further clinical trials of tumors including ARID1A mutations are warranted.