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1.
Nature ; 608(7923): 569-577, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35922514

RESUMO

A major challenge in human genetics is to identify the molecular mechanisms of trait-associated and disease-associated variants. To achieve this, quantitative trait locus (QTL) mapping of genetic variants with intermediate molecular phenotypes such as gene expression and splicing have been widely adopted1,2. However, despite successes, the molecular basis for a considerable fraction of trait-associated and disease-associated variants remains unclear3,4. Here we show that ADAR-mediated adenosine-to-inosine RNA editing, a post-transcriptional event vital for suppressing cellular double-stranded RNA (dsRNA)-mediated innate immune interferon responses5-11, is an important potential mechanism underlying genetic variants associated with common inflammatory diseases. We identified and characterized 30,319 cis-RNA editing QTLs (edQTLs) across 49 human tissues. These edQTLs were significantly enriched in genome-wide association study signals for autoimmune and immune-mediated diseases. Colocalization analysis of edQTLs with disease risk loci further pinpointed key, putatively immunogenic dsRNAs formed by expected inverted repeat Alu elements as well as unexpected, highly over-represented cis-natural antisense transcripts. Furthermore, inflammatory disease risk variants, in aggregate, were associated with reduced editing of nearby dsRNAs and induced interferon responses in inflammatory diseases. This unique directional effect agrees with the established mechanism that lack of RNA editing by ADAR1 leads to the specific activation of the dsRNA sensor MDA5 and subsequent interferon responses and inflammation7-9. Our findings implicate cellular dsRNA editing and sensing as a previously underappreciated mechanism of common inflammatory diseases.


Assuntos
Adenosina Desaminase , Predisposição Genética para Doença , Doenças do Sistema Imunitário , Inflamação , Edição de RNA , RNA de Cadeia Dupla , Adenosina/metabolismo , Adenosina Desaminase/genética , Adenosina Desaminase/metabolismo , Elementos Alu/genética , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Estudo de Associação Genômica Ampla , Humanos , Doenças do Sistema Imunitário/genética , Doenças do Sistema Imunitário/imunologia , Doenças do Sistema Imunitário/patologia , Imunidade Inata , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Inosina/metabolismo , Helicase IFIH1 Induzida por Interferon/metabolismo , Interferons/genética , Interferons/imunologia , Locos de Características Quantitativas/genética , Edição de RNA/genética , RNA de Cadeia Dupla/genética , Proteínas de Ligação a RNA/metabolismo
2.
EMBO J ; 42(2): e110553, 2023 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-36504224

RESUMO

Epithelial-mesenchymal transition (EMT) is pivotal in the initiation and development of cancer cell metastasis. We observed that the abundance of glycosphingolipids (GSLs), especially ganglioside subtypes, decreased significantly during TGF-ß-induced EMT in NMuMG mouse mammary epithelial cells and A549 human lung adenocarcinoma cells. Transcriptional profiling showed that TGF-ß/SMAD response genes and EMT signatures were strongly enriched in NMuMG cells, along with depletion of UDP-glucose ceramide glucosyltransferase (UGCG), the enzyme that catalyzes the initial step in GSL biosynthesis. Consistent with this finding, genetic or pharmacological inhibition of UGCG promoted TGF-ß signaling and TGF-ß-induced EMT. UGCG inhibition promoted A549 cell migration, extravasation in the zebrafish xenograft model, and metastasis in mice. Mechanistically, GSLs inhibited TGF-ß signaling by promoting lipid raft localization of the TGF-ß type I receptor (TßRI) and by increasing TßRI ubiquitination and degradation. Importantly, we identified ST3GAL5-synthesized a-series gangliosides as the main GSL subtype involved in inhibition of TGF-ß signaling and TGF-ß-induced EMT in A549 cells. Notably, ST3GAL5 is weakly expressed in lung cancer tissues compared to adjacent nonmalignant tissues, and its expression correlates with good prognosis.


Assuntos
Neoplasias Pulmonares , Fator de Crescimento Transformador beta , Humanos , Animais , Camundongos , Fator de Crescimento Transformador beta/metabolismo , Gangliosídeos , Transição Epitelial-Mesenquimal/genética , Peixe-Zebra/metabolismo , Neoplasias Pulmonares/metabolismo , Glicoesfingolipídeos , Catálise , Movimento Celular , Linhagem Celular Tumoral
3.
Nature ; 592(7853): 302-308, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33762732

RESUMO

Our knowledge of copy number evolution during the expansion of primary breast tumours is limited1,2. Here, to investigate this process, we developed a single-cell, single-molecule DNA-sequencing method and performed copy number analysis of 16,178 single cells from 8 human triple-negative breast cancers and 4 cell lines. The results show that breast tumours and cell lines comprise a large milieu of subclones (7-22) that are organized into a few (3-5) major superclones. Evolutionary analysis suggests that after clonal TP53 mutations, multiple loss-of-heterozygosity events and genome doubling, there was a period of transient genomic instability followed by ongoing copy number evolution during the primary tumour expansion. By subcloning single daughter cells in culture, we show that tumour cells rediversify their genomes and do not retain isogenic properties. These data show that triple-negative breast cancers continue to evolve chromosome aberrations and maintain a reservoir of subclonal diversity during primary tumour growth.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proliferação de Células , Células Clonais/metabolismo , Células Clonais/patologia , Evolução Molecular , Sequência de Bases , Linhagem Celular Tumoral , Linhagem da Célula , Aberrações Cromossômicas , Variações do Número de Cópias de DNA/genética , Análise Mutacional de DNA , Instabilidade Genômica/genética , Humanos , Perda de Heterozigosidade/genética , Modelos Genéticos , Taxa de Mutação , Imagem Individual de Molécula , Análise de Célula Única , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
4.
Proc Natl Acad Sci U S A ; 120(34): e2302738120, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37579159

RESUMO

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is characterized by various disabling symptoms including exercise intolerance and is diagnosed in the absence of a specific cause, making its clinical management challenging. A better understanding of the molecular mechanism underlying this apparent bioenergetic deficiency state may reveal insights for developing targeted treatment strategies. We report that overexpression of Wiskott-Aldrich Syndrome Protein Family Member 3 (WASF3), here identified in a 38-y-old woman suffering from long-standing fatigue and exercise intolerance, can disrupt mitochondrial respiratory supercomplex formation and is associated with endoplasmic reticulum (ER) stress. Increased expression of WASF3 in transgenic mice markedly decreased their treadmill running capacity with concomitantly impaired respiratory supercomplex assembly and reduced complex IV levels in skeletal muscle mitochondria. WASF3 induction by ER stress using endotoxin, well known to be associated with fatigue in humans, also decreased skeletal muscle complex IV levels in mice, while decreasing WASF3 levels by pharmacologic inhibition of ER stress improved mitochondrial function in the cells of the patient with chronic fatigue. Expanding on our findings, skeletal muscle biopsy samples obtained from a cohort of patients with ME/CFS showed increased WASF3 protein levels and aberrant ER stress activation. In addition to revealing a potential mechanism for the bioenergetic deficiency in ME/CFS, our study may also provide insights into other disorders associated with fatigue such as rheumatic diseases and long COVID.


Assuntos
COVID-19 , Síndrome de Fadiga Crônica , Animais , Feminino , Humanos , Camundongos , COVID-19/metabolismo , Síndrome de Fadiga Crônica/diagnóstico , Mitocôndrias/metabolismo , Síndrome de COVID-19 Pós-Aguda , Respiração , Família de Proteínas da Síndrome de Wiskott-Aldrich/metabolismo , Camundongos Transgênicos
5.
J Physiol ; 602(6): 1211-1225, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38381050

RESUMO

Gestational hypoxia adversely affects uterine artery function, increasing complications. However, an effective therapy remains unidentified. Here, we show in rodent uterine arteries that hypoxic pregnancy promotes hypertrophic remodelling, increases constrictor reactivity via protein kinase C signalling, and triggers compensatory dilatation via nitric oxide-dependent mechanisms and stimulation of large conductance Ca2+ -activated K+ -channels. Maternal in vivo oral treatment with the mitochondria-targeted antioxidant MitoQ in hypoxic pregnancy normalises uterine artery reactivity and prevents vascular remodelling. From days 6-20 of gestation (term ∼22 days), female Wistar rats were randomly assigned to normoxic or hypoxic (13-14% O2 ) pregnancy ± daily maternal MitoQ treatment (500 µm in drinking water). At 20 days of gestation, maternal, placental and fetal tissue was frozen to determine MitoQ uptake. The uterine arteries were harvested and, in one segment, constrictor and dilator reactivity was determined by wire myography. Another segment was fixed for unbiased stereological analysis of vessel morphology. Maternal administration of MitoQ in both normoxic and hypoxic pregnancy crossed the placenta and was present in all tissues analysed. Hypoxia increased uterine artery constrictor responses to norepinephrine, angiotensin II and the protein kinase C activator, phorbol 12,13-dibutyrate. Hypoxia enhanced dilator reactivity to sodium nitroprusside, the large conductance Ca2+ -activated K+ -channel activator NS1619 and ACh via increased nitric oxide-dependent mechanisms. Uterine arteries from hypoxic pregnancy showed increased wall thickness and MitoQ treatment in hypoxic pregnancy prevented all effects on uterine artery reactivity and remodelling. The data support mitochondria-targeted therapy against adverse changes in uterine artery structure and function in high-risk pregnancy. KEY POINTS: Dysfunction and remodelling of the uterine artery are strongly implicated in many pregnancy complications, including advanced maternal age, maternal hypertension of pregnancy, maternal obesity, gestational diabetes and pregnancy at high altitude. Such complications not only have immediate adverse effects on the growth of the fetus, but also they can also increase the risk of cardiovascular disease in the mother and offspring. Despite this, there is a significant unmet clinical need for therapeutics that treat uterine artery vascular dysfunction in adverse pregnancy. Here, we show in a rodent model of gestational hypoxia that in vivo oral treatment of the mitochondria-targeted antioxidant MitoQ protects against uterine artery vascular dysfunction and remodelling, supporting the use of mitochondria-targeted therapy against adverse changes in uterine artery structure and function in high-risk pregnancy.


Assuntos
Placenta , Artéria Uterina , Humanos , Ratos , Animais , Gravidez , Feminino , Placenta/metabolismo , Artéria Uterina/fisiologia , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Roedores , Óxido Nítrico/metabolismo , Ratos Wistar , Hipóxia , Proteína Quinase C/metabolismo , Mitocôndrias/metabolismo
6.
J Biol Chem ; 299(3): 103018, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36796514

RESUMO

The endosymbiotic theory posits that ancient eukaryotic cells engulfed O2-consuming prokaryotes, which protected them against O2 toxicity. Previous studies have shown that cells lacking cytochrome c oxidase (COX), required for respiration, have increased DNA damage and reduced proliferation, which could be improved by reducing O2 exposure. With recently developed fluorescence lifetime microscopy-based probes demonstrating that the mitochondrion has lower [O2] than the cytosol, we hypothesized that the perinuclear distribution of mitochondria in cells may create a barrier for O2 to access the nuclear core, potentially affecting cellular physiology and maintaining genomic integrity. To test this hypothesis, we utilized myoglobin-mCherry fluorescence lifetime microscopy O2 sensors without subcellular targeting ("cytosol") or with targeting to the mitochondrion or nucleus for measuring their localized O2 homeostasis. Our results showed that, similar to the mitochondria, the nuclear [O2] was reduced by ∼20 to 40% compared with the cytosol under imposed O2 levels of ∼0.5 to 18.6%. Pharmacologically inhibiting respiration increased nuclear O2 levels, and reconstituting O2 consumption by COX reversed this increase. Similarly, genetic disruption of respiration by deleting SCO2, a gene essential for COX assembly, or restoring COX activity in SCO2-/- cells by transducing with SCO2 cDNA replicated these changes in nuclear O2 levels. The results were further supported by the expression of genes known to be affected by cellular O2 availability. Our study reveals the potential for dynamic regulation of nuclear O2 levels by mitochondrial respiratory activity, which in turn could affect oxidative stress and cellular processes such as neurodegeneration and aging.


Assuntos
Mitocôndrias , Oxigênio , Oxigênio/metabolismo , Mitocôndrias/metabolismo , Respiração , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Núcleo Celular/metabolismo , Consumo de Oxigênio , Respiração Celular
7.
J Am Chem Soc ; 146(30): 21147-21159, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39013150

RESUMO

Driven by the essential need of a green, safe, and low-cost approach to producing H2O2, a highly valuable multifunctional chemical, artificial photosynthesis emerges as a promising avenue. However, current catalyst systems remain challenging, due to the need of high-density sunlight, poor selectivity and activity, or/and unfavorable thermodynamics. Here, we reported that an indirect 2e- water oxidation reaction (WOR) in photocatalytic H2O2 production was unusually activated by C5N2 with piezoelectric effects. Interestingly, under ultrasonication, C5N2 exhibited an overall H2O2 photosynthesis rate of 918.4 µM/h and an exceptionally high solar-to-chemical conversion efficiency of 2.6% after calibration under weak light (0.1 sun). Mechanism studies showed that the piezoelectric effect of carbon nitride overcame the high uphill thermodynamics of *OH intermediate generation, which enabled a new pathway for 2e- WOR, the kinetic limiting step in the overall H2O2 production from H2O and O2. Benefiting from the outstanding sonication-assisted photocatalytic H2O2 generation under weak light, the concept was further successfully adapted to biomedical applications in efficient sono-photochemodynamic therapy for cancer treatment and water purification.

8.
Mol Cancer ; 23(1): 91, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38715012

RESUMO

BACKGROUND: Recent evidence has demonstrated that abnormal expression and regulation of circular RNA (circRNAs) are involved in the occurrence and development of a variety of tumors. The aim of this study was to investigate the effects of circ_PPAPDC1A in Osimertinib resistance in NSCLC. METHODS: Human circRNAs microarray analysis was conducted to identify differentially expressed (DE) circRNAs in Osimertinib-acquired resistance tissues of NSCLC. The effect of circ_PPAPDC1A on cell proliferation, invasion, migration, and apoptosis was assessed in both in vitro and in vivo. Dual-luciferase reporter assay, RT-qPCR, Western-blot, and rescue assay were employed to confirm the interaction between circ_PPAPDC1A/miR-30a-3p/IGF1R axis. RESULTS: The results revealed that circ_PPAPDC1A was significantly upregulated in Osimertinib acquired resistance tissues of NSCLC. circ_PPAPDC1A reduced the sensitivity of PC9 and HCC827 cells to Osimertinib and promoted cell proliferation, invasion, migration, while inhibiting apoptosis in Osimertinib-resistant PC9/OR and HCC829/OR cells, both in vitro and in vivo. Silencing circ_PPAPDC1A partially reversed Osimertinib resistance. Additionally, circ_PPAPDC1A acted as a competing endogenous RNA (ceRNA) by targeting miR-30a-3p, and Insulin-like Growth Factor 1 Receptor (IGF1R) was identified as a functional gene for miR-30a-3p in NSCLC. Furthermore, the results confirmed that circ_PPAPDC1A/miR-30a-3p/IGF1R axis plays a role in activating the PI3K/AKT/mTOR signaling pathway in NSCLC with Osimertinib resistance. CONCLUSIONS: Therefore, for the first time we identified that circ_PPAPDC1A was significantly upregulated and exerts an oncogenic role in NSCLC with Osimertinib resistance by sponging miR-30a-3p to active IGF1R/PI3K/AKT/mTOR pathway. circ_PPAPDC1A may serve as a novel diagnostic biomarker and therapeutic target for NSCLC patients with Osimertinib resistance.


Assuntos
Acrilamidas , Compostos de Anilina , Carcinoma Pulmonar de Células não Pequenas , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares , MicroRNAs , RNA Circular , Receptor IGF Tipo 1 , Transdução de Sinais , Humanos , MicroRNAs/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Acrilamidas/farmacologia , RNA Circular/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Compostos de Anilina/farmacologia , Linhagem Celular Tumoral , Animais , Camundongos , Apoptose , Movimento Celular/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Masculino , Feminino , Indóis , Pirimidinas
9.
Br J Cancer ; 130(11): 1819-1827, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38594370

RESUMO

BACKGROUND: Although DHFR gene amplification has long been known as a major mechanism for methotrexate (MTX) resistance in cancer, the early changes and detailed development of the resistance are not yet fully understood. METHODS: We performed genomic, transcriptional and proteomic analyses of human colon cancer cells with sequentially increasing levels of MTX-resistance. RESULTS: The genomic amplification evolved in three phases (pre-amplification, homogenously staining region (HSR) and extrachromosomal DNA (ecDNA)). We confirm that genomic amplification and increased expression of DHFR, with formation of HSRs and especially ecDNAs, is the major driver of resistance. However, DHFR did not play a detectable role in the early phase. In the late phase (ecDNA), increase in FAM151B protein level may also have an important role by decreasing sensitivity to MTX. In addition, although MSH3 and ZFYVE16 may be subject to different posttranscriptional regulations and therefore protein expressions are decreased in ecDNA stages compared to HSR stages, they still play important roles in MTX resistance. CONCLUSION: The study provides a detailed evolutionary trajectory of MTX-resistance and identifies new targets, especially ecDNAs, which could help to prevent drug resistance. It also presents a proof-of-principal approach which could be applied to other cancer drug resistance studies.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Amplificação de Genes , Metotrexato , Tetra-Hidrofolato Desidrogenase , Humanos , Metotrexato/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Tetra-Hidrofolato Desidrogenase/genética , Tetra-Hidrofolato Desidrogenase/metabolismo , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Antimetabólitos Antineoplásicos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genômica/métodos
10.
Am J Transplant ; 24(6): 1057-1069, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38307417

RESUMO

Although cytomegalovirus (CMV) viremia/DNAemia has been associated with reduced survival after lung transplantation, its association with chronic lung allograft dysfunction (CLAD) and its phenotypes is unclear. We hypothesized that, in a modern era of CMV prophylaxis, CMV DNAemia would still remain associated with death, but also represent a risk factor for CLAD and specifically restrictive allograft syndrome (RAS)/mixed phenotype. This was a single-center retrospective cohort study of all consecutive adult, first, bilateral-/single-lung transplants done between 2010-2016, consisting of 668 patients. Risks for death/retransplantation, CLAD, or RAS/mixed, were assessed by adjusted cause-specific Cox proportional-hazards models. CMV viral load (VL) was primarily modeled as a categorical variable: undetectable, detectable to 999, 1000 to 9999, and ≥10 000 IU/mL. In multivariable models, CMV VL was significantly associated with death/retransplantation (≥10 000 IU/mL: HR = 2.65 [1.78-3.94]; P < .01), but was not associated with CLAD, whereas CMV serostatus mismatch was (D+R-: HR = 2.04 [1.30-3.21]; P < .01). CMV VL was not associated with RAS/mixed in univariable analysis. Secondary analyses with a 7-level categorical or 4-level ordinal CMV VL confirmed similar results. In conclusion, CMV DNAemia is a significant risk factor for death/retransplantation, but not for CLAD or RAS/mixed. CMV serostatus mismatch may have an impact on CLAD through a pathway independent of DNAemia.


Assuntos
Infecções por Citomegalovirus , Citomegalovirus , Rejeição de Enxerto , Sobrevivência de Enxerto , Transplante de Pulmão , Complicações Pós-Operatórias , Viremia , Humanos , Transplante de Pulmão/efeitos adversos , Infecções por Citomegalovirus/virologia , Infecções por Citomegalovirus/epidemiologia , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Viremia/virologia , Viremia/epidemiologia , Citomegalovirus/isolamento & purificação , Fatores de Risco , Seguimentos , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/virologia , Prognóstico , Complicações Pós-Operatórias/virologia , Complicações Pós-Operatórias/epidemiologia , Adulto , Carga Viral , Taxa de Sobrevida , Transplantados/estatística & dados numéricos
11.
Apoptosis ; 29(9-10): 1600-1618, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39110356

RESUMO

High-altitude pulmonary edema (HAPE) is a fatal threat for sojourners who ascend rapidly without sufficient acclimatization. Acclimatized sojourners and adapted natives are both insensitive to HAPE but have different physiological traits and molecular bases. In this study, based on GSE52209, the gene expression profiles of HAPE patients were compared with those of acclimatized sojourners and adapted natives, with the common and divergent differentially expressed genes (DEGs) and their hub genes identified, respectively. Bioinformatic methodologies for functional enrichment analysis, immune infiltration, diagnostic model construction, competing endogenous RNA (ceRNA) analysis and drug prediction were performed to detect potential biological functions and molecular mechanisms. Next, an array of in vivo experiments in a HAPE rat model and in vitro experiments in HUVECs were conducted to verify the results of the bioinformatic analysis. The enriched pathways of DEGs and immune landscapes for HAPE were significantly different between sojourners and natives, and the common DEGs were enriched mainly in the pathways of development and immunity. Nomograms revealed that the upregulation of TNF-α and downregulation of RPLP0 exhibited high diagnostic efficiency for HAPE in both sojourners and natives, which was further validated in the HAPE rat model. The addition of TNF-α and RPLP0 knockdown activated apoptosis signaling in endothelial cells (ECs) and enhanced endothelial permeability. In conclusion, TNF-α and RPLP0 are shared biomarkers and molecular bases for HAPE susceptibility during the acclimatization/adaptation/maladaptation processes in sojourners and natives, inspiring new ideas for predicting and treating HAPE.


Assuntos
Doença da Altitude , Apoptose , Células Endoteliais , Proteínas Ribossômicas , Fator de Necrose Tumoral alfa , Animais , Humanos , Masculino , Ratos , Altitude , Doença da Altitude/genética , Doença da Altitude/metabolismo , Doença da Altitude/patologia , Apoptose/genética , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo
12.
Anal Chem ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39263911

RESUMO

Eu isotopes are promising tracers across various scientific domains such as planetary, earth, and marine science, yet their high-precision analysis has been challenging due to the similar geochemical properties of rare earth elements (REEs). In this study, a novel two-column chromatographic approach was developed utilizing AG50W-X12 and TODGA resins to separate Eu effectively from matrix and interfering elements like Ba, Nd, Sm, and Gd, while ensuring high Eu yields (99.4 ± 0.4%, n = 19) and low blanks (<20 pg). The robustness of this method is evidenced by various rock types and different Eu loading masses. The efficient purification of Eu facilitated the establishment of a high-precision calibration technique with standard-sample bracketing (SSB) and internal normalization (Nd). When a Nu Plasma 1700 multicollector-inductively coupled plasma-mass spectrometry (MC-ICP-MS) instrument was employed, repeated purification and analysis of various Geological Reference Materials (GRMs) confirmed that the long-term external precision of δ153/151Eu is better than 0.04‰ (2 standard deviation (2SD)), which represents a 2-5-fold increase in precision compared to previously reported methods. Additionally, the high-precision Eu isotopic compositions of five GRMs, including basalts, andesite, syenite, and marine sediment, were measured. The high-precision Eu isotope techniques presented herein open up new avenues for Eu isotope geochemistry.

13.
Biochem Biophys Res Commun ; 710: 149884, 2024 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-38598901

RESUMO

In the clinical setting, chemotherapy is the most widely used antitumor treatment, however, chemotherapy resistance significantly limits its efficacy. Reduced drug influx is a key mechanism of chemoresistance, and inhibition of the complexity of the tumor microenvironment (TME) may improve chemotherapy drug influx and therapeutic efficiency. In the current study, we identified that the major extracellular matrix protein collagen I is more highly expressed in lung cancer tissues than adjacent tissues in patients with lung cancer. Furthermore, Kaplan-Meier analysis suggested that COL1A1 expression was negatively correlated with the survival time of patients with lung cancer. Our previous study demonstrated that miR-29a inhibited collagen I expression in lung fibroblasts. Here, we investigated the effect of miR-29a on collagen I expression and the cellular behavior of lung cancer cells. Our results suggest that transfection with miR-29a could prevent Lewis lung carcinoma (LLC) migration by downregulating collagen I expression, but did not affect the proliferation, apoptosis, and cell cycle of LLC cells. In a 3D tumoroid model, we demonstrated that miR-29a transfection significantly increased cisplatin (CDDP) permeation and CDDP-induced cell death. Furthermore, neutral lipid emulsion-based miR-29a delivery improved the therapeutic effect of cisplatin in an LLC spontaneous tumor model in vivo. In summary, this study shows that targeting collagen I expression in the TME contributes to chemotherapy drug influx and improves therapeutic efficacy in lung cancer.


Assuntos
Neoplasias Pulmonares , MicroRNAs , Humanos , Linhagem Celular Tumoral , Proliferação de Células , Cisplatino/farmacologia , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , MicroRNAs/metabolismo , MicroRNAs/farmacologia , Permeabilidade , Microambiente Tumoral
14.
Cancer Immunol Immunother ; 73(8): 143, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38832955

RESUMO

This study investigates the role of USP47, a deubiquitinating enzyme, in the tumor microenvironment and its impact on antitumor immune responses. Analysis of TCGA database revealed distinct expression patterns of USP47 in various tumor tissues and normal tissues. Prostate adenocarcinoma showed significant downregulation of USP47 compared to normal tissue. Correlation analysis demonstrated a positive association between USP47 expression levels and infiltrating CD8+ T cells, neutrophils, and macrophages, while showing a negative correlation with NKT cells. Furthermore, using Usp47 knockout mice, we observed a slower tumor growth rate and reduced tumor burden. The absence of USP47 led to increased infiltration of immune cells, including neutrophils, macrophages, NK cells, NKT cells, and T cells. Additionally, USP47 deficiency resulted in enhanced activation of cytotoxic T lymphocytes (CTLs) and altered T cell subsets within the tumor microenvironment. These findings suggest that USP47 plays a critical role in modulating the tumor microenvironment and promoting antitumor immune responses, highlighting its potential as a therapeutic target in prostate cancer.


Assuntos
Linfócitos do Interstício Tumoral , Neoplasias da Próstata , Animais , Humanos , Masculino , Camundongos , Linhagem Celular Tumoral , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Microambiente Tumoral
15.
Small ; 20(29): e2309859, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38377282

RESUMO

Designing and fabricating highly efficient oxygen evolution reaction (OER) electrocatalytic materials for water splitting is a promising and practical approach to green and sustainable low-carbon energy systems. Herein, a facile in situ growth self-template strategy by using ZIF-67 as a consumable layered double hydroxides (LDHs) template and silver nanowires (AgNWs) as 1D conductive cascaded substrate to controllably synthesize the target AgNWs@CoFe-LDH composites with unique hollow shell sugar gourd-like structure and enhanced directional electron transport effect is reported. The AgNWs exhibit the key functions of the close connection of CoFe-LDH nanocages and the support of the directional electron transport effect in the composite catalyst inducing electrons directionally moving from CoFe-LDH to AgNWs. Meanwhile, the CoFe-LDH nanocages with ultrathin nanosheets and hollow structural properties show abundant active sites for electrocatalytic oxygen generation. The versatile AgNWs@CoFe-LDH catalyst with optimized components, enhanced directional electron transport, and synergistic effect achieves high OER performance with the overpotential of 207 mV and long-term 50 h stability at 10 mA cm-2 in an alkaline medium. Moreover, in-depth insights into the microstructure, structure-activity relationships, identification of key intermediate species, and a proton-coupled four-electron OER mechanism based on experimental discovery and theoretical calculation are also demonstrated.

16.
Clin Sci (Lond) ; 138(3): 103-115, 2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-38237016

RESUMO

High-altitude pulmonary hypertension (HAPH) is a severe and progressive disease that can lead to right heart failure. Intermittent short-duration reoxygenation at high altitude is effective in alleviating HAPH; however, the underlying mechanisms are unclear. In the present study, a simulated 5,000-m hypoxia rat model and hypoxic cultured pulmonary artery smooth muscle cells (PASMCs) were used to evaluate the effect and mechanisms of intermittent short-duration reoxygenation. The results showed that intermittent 3-h/per day reoxygenation (I3) effectively attenuated chronic hypoxia-induced pulmonary hypertension and reduced the content of H2O2 and the expression of NADPH oxidase 4 (NOX4) in lung tissues. In combination with I3, while the NOX inhibitor apocynin did not further alleviate HAPH, the mitochondrial antioxidant MitoQ did. Furthermore, in PASMCs, I3 attenuated hypoxia-induced PASMCs proliferation and reversed the activated HIF-1α/NOX4/PPAR-γ axis under hypoxia. Targeting this axis offset the protective effect of I3 on hypoxia-induced PASMCs proliferation. The present study is novel in revealing a new mechanism for preventing HAPH and provides insights into the optimization of intermittent short-duration reoxygenation.


Assuntos
Doença da Altitude , Hipertensão Pulmonar , Animais , Ratos , Altitude , Proliferação de Células , Células Cultivadas , Peróxido de Hidrogênio/metabolismo , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/prevenção & controle , Hipertensão Pulmonar/metabolismo , Hipóxia/metabolismo , Miócitos de Músculo Liso/metabolismo , NADPH Oxidase 4/genética , NADPH Oxidase 4/metabolismo , PPAR gama/metabolismo , Artéria Pulmonar/metabolismo , Transdução de Sinais
17.
Am J Bot ; : e16427, 2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39431323

RESUMO

PREMISE: The expected concomitant increase in multiple stressors such as herbivory and drought may threaten peatland ecosystems. How Sphagnum, the ecological engineers of peatlands, responds to combined stressors remains largely unexplored. Here we aimed to clarify resource allocations in Sphagnum during concomitant herbivory and drought. METHODS: S. magellanicum and S. fuscum were exposed to drought and herbivory together or separately in laboratory experiments and analyzed for growth (biomass production and net photosynthetic rate), defense (phenolics in leachates and phenolics in extraction) and nonstructural carbohydrates (soluble sugar and starch) in relation to untreated controls. RESULTS: Herbivory and drought had significant interactive effects on Sphagnum growth and defense. In both species, drought without herbivory reduced the phenolics in leachate, but with herbivory increased phenolics, indicating a synergistic effect between herbivory and drought on Sphagnum defense. Both stressors significantly decreased biomass production, with the combined stress having a more negative effect. Interestingly, a growth-defense trade-off was found in the drought treatment of both Sphagnum species, but disappeared in the wet treatment. Conversely, a trade-off between soluble sugars and phenolics was found in the wet but not in the drought treatment, suggesting that soluble sugars may play a role in inducing the defense and hence mask the growth-defense trade-off in peat mosses. CONCLUSIONS: Our results emphasize that predicting the impact of combined stressors on peat moss traits is complex and challenging. Future models should account for the effects of multiple environmental stressors to guide peatland conservation under climate warming.

18.
BMC Gastroenterol ; 24(1): 360, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39390389

RESUMO

BACKGROUND AND AIMS: Several risk models for esophageal stricture after endoscopic submucosal dissection have been developed. However, some of them did not include the use of steroids in the risk analysis. Glucocorticoid sensitivity mediated by glucocorticoid receptor expression has not been discussed in this condition. METHODS: Clinical and endoscopic characteristics were included in the logistic regression model to establish a nomogram for stenosis prediction. The score for each risk factor was estimated. Risk factors of ineffective oral steroid prophylaxis were analyzed and glucocorticoid receptor expressions were detected by immunohistochemistry. RESULTS: Three hundred fourteen patients of endoscopic submucosal dissection for esophageal superficial neoplasms were included to develop the nomogram. The circumferential range(≤ 3/4, 3/4-1 or the whole circumference), longitudinal diameter reached 4 cm (yes or not) and lesion location (the cervical and upper thoracic part, the middle thoracic part or the lower thoracic part) consisted of the nomogram. Patients have a high risk of esophageal stricture if they have a total point greater than 36. In the simplified risk score model, the corresponding cutoff score was 1. 92 patients with oral steroid prophylaxis were separately analyzed and the circumferential mucosal defect involving 7/8 or more was an independent risk factor of ineffective prevention (OR 12.2, 95%CI 5.27-28.11). The expression of glucocorticoid receptor ß was higher in the stricture group (p = 0.042 for AOD; p = 0.016 for the scoring system). CONCLUSIONS: We established a nomogram for esophageal stricture prediction. Depending on the characteristics of lesions, it is possible to estimate the risk of stricture under routine post-ESD treatments (no steroids or oral steroids). Alternative treatments should be considered if the risk is extremely high, especially for patients with mucosal defects involving 7/8 or more of circumference in which oral steroid treatment tends to be ineffective. The higher glucocorticoid receptor ß may indicate potential glucocorticoid resistance.


Assuntos
Ressecção Endoscópica de Mucosa , Neoplasias Esofágicas , Estenose Esofágica , Nomogramas , Receptores de Glucocorticoides , Humanos , Feminino , Masculino , Fatores de Risco , Receptores de Glucocorticoides/metabolismo , Estenose Esofágica/prevenção & controle , Estenose Esofágica/etiologia , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/patologia , Pessoa de Meia-Idade , Idoso , Ressecção Endoscópica de Mucosa/efeitos adversos , Glucocorticoides/administração & dosagem , Glucocorticoides/efeitos adversos , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Administração Oral , Medição de Risco , Modelos Logísticos
19.
Lipids Health Dis ; 23(1): 301, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39285295

RESUMO

BACKGROUND: Low-density lipoprotein cholesterol (LDL-C) is acknowledged as an independent risk factor (IRF) for atherosclerotic cardiovascular disease. Nevertheless, studies on the impact of LDL-C on microvasculature are still scarce. The retina, abundant in microvasculature, can now be examined for microvascular alterations through the novel, non-invasive, and quantitative optical coherence tomography angiography (OCTA) technique. METHODS: In this cross-sectional study, 243 patients from the geriatric department were recruited (between December 2022 and December 2023). Individuals were classified into four groups based on their LDL-C levels: Group 1 (≤ 1.8 mmol/L), Group 2 (> 1.8 mmol/L to ≤ 2.6 mmol/L), Group 3 (> 2.6 mmol/L to ≤ 3.4 mmol/L), and Group 4 (> 3.4 mmol/L). The OCTA results including retinal vessel density (VD), foveal avascular zone (FAZ) area, macula thickness, and retinal nerve fiber layer (RNFL) thickness were contrasted across these groups. T-tests, analysis of variance, Welch's tests, or rank-sum tests were employed for statistical comparisons. In cases where significant differences between groups were found, post-hoc multiple comparisons or rank-sum tests were performed for pairwise group comparisons. Spearman's correlation coefficient was employed to perform bivariate correlation analysis to evaluate the relationship between LDL-C levels and various OCTA measurements. Multivariable regression analysis was used to evaluate the association between LDL-C levels and various OCTA measurements. Linear regression analysis or mixed-effects linear models were applied. RESULTS: It was discovered that individuals with LDL-C levels exceeding 2.6 mmol/L (Groups 3 and 4) exhibited reduced VD in the retina, encompassing both the optic disc and macular regions, compared to those with LDL-C levels at or below 2.6 mmol/L (Groups 1 and 2). A negative correlation among LDL-C levels and retinal VD was identified, with r values spanning from - 0.228 to -0.385. Further regression analysis presented ß values between - 0.954 and - 2.378. Additionally, no notable disparities were detected among the groups regarding FAZ area, macular thickness, and RNFL thickness. CONCLUSIONS: The outcomes of this study suggest that elevated LDL-C levels constitute an IRF for decreased VD across the entire retina. TRIAL REGISTRATION: NCT05644548, December 1, 2022.


Assuntos
LDL-Colesterol , Vasos Retinianos , Tomografia de Coerência Óptica , Humanos , Tomografia de Coerência Óptica/métodos , Masculino , Feminino , Vasos Retinianos/diagnóstico por imagem , LDL-Colesterol/sangue , Idoso , Estudos Transversais , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Macula Lutea/diagnóstico por imagem , Macula Lutea/irrigação sanguínea , Fatores de Risco
20.
Ecotoxicol Environ Saf ; 272: 116059, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38309235

RESUMO

Alfalfa (Medicago sativa L.) is a feed crop due to its rich nutrition and high productivity. The utilization of titanium oxide nanoparticles (TiO2 NPs) brings benefits to agricultural production but also has potential hazards. To investigate the duality and related mechanism of TiO2 NPs on alfalfa, its different doses including 0, 50, 100, 200, 500, and 1000 mg L- 1 (CK, Ti-50, Ti-100, Ti-200, Ti-500, and Ti-1000) were sprayed on leaves. The results showed that greater doses of TiO2 NPs (500 and 1000 mg L-1) negatively affected the physiological parameters, including morphology, biomass, leaf ultrastructure, stomata, photosynthesis, pigments, and antioxidant ability. However, 100 mg L-1 TiO2 NPs revealed an optimal positive effect; compared with the CK, it dramatically increased plant height, fresh weight, and dry weight by 22%, 21%, and 41%, respectively. Additionally, TiO2 NPs at low doses significantly protected leaf tissue, promoted stomatal opening, and enhanced the antioxidant system; while higher doses had phytotoxicity. Hence, TiO2 NPs are dose-dependent on alfalfa. The transcriptomic analysis identified 4625 and 2121 differentially expressed genes (DEGs) in the comparison of CK vs. Ti-100 and CK vs. Ti-500, respectively. They were mainly enriched in photosynthesis, chlorophyll metabolism, and energy metabolism. Notably, TiO2 NPs-induced phytotoxicity on photosynthetic parameters happened concurrently with the alterations of the genes involved in the porphyrin and chlorophyll metabolism and carbon fixation in photosynthetic organisms in the KEGG analysis. Similarly, it affected the efficiency of alfalfa energy transformation processes, including pyruvate metabolism and chlorophyll synthesis. Several key related genes in these pathways were validated. Therefore, TiO2 NPs have positive and toxic effects by regulating morphology, leaf ultrastructure, stomata, photosynthesis, redox homeostasis, and genes related to key pathways. It is significant to understand the duality of TiO2 NPs and cultivate varieties resistant to nanomaterial pollution.


Assuntos
Medicago sativa , Nanopartículas , Medicago sativa/metabolismo , Antioxidantes/metabolismo , Nanopartículas/toxicidade , Perfilação da Expressão Gênica , Clorofila/metabolismo
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