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1.
Circulation ; 150(11): 867-883, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-38804138

RESUMO

BACKGROUND: Pulmonary hypertension (PH) is a major complication linked to adverse outcomes in heart failure with preserved ejection fraction (HFpEF), yet no specific therapies exist for PH associated with HFpEF (PH-HFpEF). We have recently reported on the role of skeletal muscle SIRT3 (sirtuin-3) in modulation of PH-HFpEF, suggesting a novel endocrine signaling pathway for skeletal muscle modulation of pulmonary vascular remodeling. METHODS: Using skeletal muscle-specific Sirt3 knockout mice (Sirt3skm-/-) and mass spectrometry-based comparative secretome analysis, we attempted to define the processes by which skeletal muscle SIRT3 defects affect pulmonary vascular health in PH-HFpEF. RESULTS: Sirt3skm-/- mice exhibited reduced pulmonary vascular density accompanied by pulmonary vascular proliferative remodeling and elevated pulmonary pressures. Comparative analysis of secretome by mass spectrometry revealed elevated secretion levels of LOXL2 (lysyl oxidase homolog 2) in SIRT3-deficient skeletal muscle cells. Elevated circulation and protein expression levels of LOXL2 were also observed in plasma and skeletal muscle of Sirt3skm-/- mice, a rat model of PH-HFpEF, and humans with PH-HFpEF. In addition, expression levels of CNPY2 (canopy fibroblast growth factor signaling regulator 2), a known proliferative and angiogenic factor, were increased in pulmonary artery endothelial cells and pulmonary artery smooth muscle cells of Sirt3skm-/- mice and animal models of PH-HFpEF. CNPY2 levels were also higher in pulmonary artery smooth muscle cells of subjects with obesity compared with nonobese subjects. Moreover, treatment with recombinant LOXL2 protein promoted pulmonary artery endothelial cell migration/proliferation and pulmonary artery smooth muscle cell proliferation through regulation of CNPY2-p53 signaling. Last, skeletal muscle-specific Loxl2 deletion decreased pulmonary artery endothelial cell and pulmonary artery smooth muscle cell expression of CNPY2 and improved pulmonary pressures in mice with high-fat diet-induced PH-HFpEF. CONCLUSIONS: This study demonstrates a systemic pathogenic impact of skeletal muscle SIRT3 deficiency in remote pulmonary vascular remodeling and PH-HFpEF. This study suggests a new endocrine signaling axis that links skeletal muscle health and SIRT3 deficiency to remote CNPY2 regulation in the pulmonary vasculature through myokine LOXL2. Our data also identify skeletal muscle SIRT3, myokine LOXL2, and CNPY2 as potential targets for the treatment of PH-HFpEF.


Assuntos
Insuficiência Cardíaca , Hipertensão Pulmonar , Camundongos Knockout , Músculo Esquelético , Sirtuína 3 , Volume Sistólico , Remodelação Vascular , Animais , Sirtuína 3/metabolismo , Sirtuína 3/deficiência , Sirtuína 3/genética , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/etiologia , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/patologia , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Camundongos , Humanos , Masculino , Ratos , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia , Artéria Pulmonar/fisiopatologia , Modelos Animais de Doenças , Feminino
2.
Arterioscler Thromb Vasc Biol ; 44(7): 1570-1583, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38813697

RESUMO

BACKGROUND: Pulmonary hypertension (PH) represents an important phenotype in heart failure with preserved ejection fraction (HFpEF). However, management of PH-HFpEF is challenging because mechanisms involved in the regulation of PH-HFpEF remain unclear. METHODS: We used a mass spectrometry-based comparative plasma proteomics approach as a sensitive and comprehensive hypothesis-generating discovery technique to profile proteins in patients with PH-HFpEF and control subjects. We then validated and investigated the role of one of the identified proteins using in vitro cell cultures, in vivo animal models, and independent cohort of human samples. RESULTS: Plasma proteomics identified high protein abundance levels of B2M (ß2-microglobulin) in patients with PH-HFpEF. Interestingly, both circulating and skeletal muscle levels of B2M were increased in mice with skeletal muscle SIRT3 (sirtuin-3) deficiency or high-fat diet-induced PH-HFpEF. Plasma and muscle biopsies from a validation cohort of PH-HFpEF patients were found to have increased B2M levels, which positively correlated with disease severity, especially pulmonary capillary wedge pressure and right atrial pressure at rest. Not only did the administration of exogenous B2M promote migration/proliferation in pulmonary arterial vascular endothelial cells but it also increased PCNA (proliferating cell nuclear antigen) expression and cell proliferation in pulmonary arterial vascular smooth muscle cells. Finally, B2m deletion improved glucose intolerance, reduced pulmonary vascular remodeling, lowered PH, and attenuated RV hypertrophy in mice with high-fat diet-induced PH-HFpEF. CONCLUSIONS: Patients with PH-HFpEF display higher circulating and skeletal muscle expression levels of B2M, the magnitude of which correlates with disease severity. Our findings also reveal a previously unknown pathogenic role of B2M in the regulation of pulmonary vascular proliferative remodeling and PH-HFpEF. These data suggest that circulating and skeletal muscle B2M can be promising targets for the management of PH-HFpEF.


Assuntos
Modelos Animais de Doenças , Insuficiência Cardíaca , Hipertensão Pulmonar , Proteômica , Volume Sistólico , Microglobulina beta-2 , Adulto , Idoso , Animais , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Microglobulina beta-2/genética , Microglobulina beta-2/sangue , Microglobulina beta-2/metabolismo , Biomarcadores/sangue , Estudos de Casos e Controles , Movimento Celular , Proliferação de Células , Células Cultivadas , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/genética , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/sangue , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Esquelético/metabolismo , Proteômica/métodos , Artéria Pulmonar/fisiopatologia , Artéria Pulmonar/metabolismo , Sirtuína 3/genética , Sirtuína 3/metabolismo , Remodelação Vascular , Função Ventricular Esquerda
3.
J Med Genet ; 61(2): 176-181, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-37798098

RESUMO

BACKGROUND: Expanded genetic screening before conception or during prenatal care can provide a more comprehensive evaluation of heritable fetal diseases. This study aimed to provide a large cohort to evaluate the significance of expanded carrier screening and to consolidate the role of expanded genetic screening in prenatal care. METHODS: This multicentre, retrospective cohort study was conducted between 31 December 2019 and 21 July 2022. A screening panel containing 302 genes and next-generation sequencing were used for the evaluation. The patients were referred from obstetric clinics, infertility centres and medical centres. Genetic counsellors conducted consultation for at least 15 min before and after screening. RESULTS: A total of 1587 patients were screened, and 653 pairs were identified. Among the couples who underwent the screening, 62 (9.49%) had pathogenic variants detected on the same genes. In total, 212 pathogenic genes were identified in this study. A total of 1173 participants carried at least one mutated gene, with a positive screening rate of 73.91%. Among the pathogenic variants that were screened, the gene encoding gap junction beta-2 (GJB2) exhibited the highest prevalence, amounting to 19.85%. CONCLUSION: Next-generation sequencing carrier screening provided additional information that may alter prenatal obstetric care by 9.49%. Pan-ethnic genetic screening and counselling should be suggested for couples of fertile age.


Assuntos
Aconselhamento , Testes Genéticos , Gravidez , Feminino , Humanos , Triagem de Portadores Genéticos , Estudos Retrospectivos , Estudos Prospectivos
4.
J Biol Chem ; 299(7): 104874, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37257819

RESUMO

Force and torque spectroscopy have provided unprecedented insights into the mechanical properties, conformational transitions, and dynamics of DNA and DNA-protein complexes, notably nucleosomes. Reliable single-molecule manipulation measurements require, however, specific and stable attachment chemistries to tether the molecules of interest. Here, we present a functionalization strategy for DNA that enables high-yield production of constructs for torsionally constrained and very stable attachment. The method is based on two subsequent PCRs: first ∼380 bp long DNA strands are generated that contain multiple labels, which are used as "megaprimers" in a second PCR to generate ∼kbp long double-stranded DNA constructs with multiple labels at the respective ends. To achieve high-force stability, we use dibenzocyclooctyne-based click chemistry for covalent attachment to the surface and biotin-streptavidin coupling to the bead. The resulting tethers are torsionally constrained and extremely stable under load, with an average lifetime of 70 ± 3 h at 45 pN. The high yield of the approach enables nucleosome reconstitution by salt dialysis on the functionalized DNA, and we demonstrate proof-of-concept measurements on nucleosome assembly statistics and inner turn unwrapping under force. We anticipate that our approach will facilitate a range of studies of DNA interactions and nucleoprotein complexes under forces and torques.


Assuntos
DNA , Nucleossomos , DNA/química , Fenômenos Mecânicos , Fenômenos Biofísicos , Reação em Cadeia da Polimerase
5.
Immunology ; 172(3): 486-499, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38547355

RESUMO

To explore the effect of K33 only mutant ubiquitin (K33O) on bone marrow-derived dendritic cells' (BMDCs') maturity, antigen uptake capability, surface molecule expressions and BMDC-mediated CTL priming, and further investigate the role of PI3K-Akt engaged in K33O-increased BMDC maturation, antigen uptake and presentation, surface molecule expressions and BMDC-based CTL priming. BMDCs were conferred K33O and other ubiquitin mutants (K33R, K48R, K63R-mutant ubiquitin) incubation or LY294002 and wortmannin pretreatment. PI3K-Akt phosphorylation, antigen uptake, antigenic presentation and CD86/MHC class I expression in BMDC were determined by western blot or flow cytometry. BMDC-based CTL proliferation and priming were determined by in vitro mixed lymphocyte reaction (MLR), ex vivo enzyme-linked immunospot assay (Elispot) and flow cytometry with intracellular staining, respectively. The treatment with K33O effectively augmented PI3K-Akt phosphorylation, BMDCs' antigen uptake, antigenic presentation, CD86/MHC class I and CD11c expressions. MLR, Elispot and flow cytometry revealed that K33O treatment obviously enhanced CTL proliferation, CTL priming and perforin/granzyme B expression. The pretreatment with PI3K-Akt inhibitors efficiently abrogated K33O's effects on BMDC. The replenishment of K33 only mutant ubiquitin augments BMDC-mediated CTL priming in bone marrow-derived dendritic cells via PI3K-Akt signalling.


Assuntos
Apresentação de Antígeno , Células da Medula Óssea , Células Dendríticas , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Linfócitos T Citotóxicos , Ubiquitina , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Animais , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ubiquitina/metabolismo , Linfócitos T Citotóxicos/imunologia , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Apresentação de Antígeno/imunologia , Camundongos Endogâmicos C57BL , Fosforilação , Ativação Linfocitária , Diferenciação Celular , Mutação , Morfolinas/farmacologia , Teste de Cultura Mista de Linfócitos , Proliferação de Células , Antígeno B7-2/metabolismo , Antígeno B7-2/genética , Antígeno B7-2/imunologia , Células Cultivadas , Cromonas/farmacologia , Wortmanina/farmacologia , Androstadienos/farmacologia
6.
Mol Carcinog ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136583

RESUMO

Xenotropic and polytropic retrovirus receptor 1 (XPR1) is the only known transporter associated with Pi efflux in mammals, and its impact on tumor progression is gradually being revealed. However, the role of XPR1 in hepatocellular carcinoma (HCC) is unknown. A bioinformatics screen for the phosphate exporter XPR1 was performed in HCC patients. The expression of XPR1 in clinical specimens was analyzed using quantitative real-time PCR, Western blot analysis, and immunohistochemical assays. Knockdown of the phosphate exporter XPR1 was performed by shRNA transfection to investigate the cellular phenotype and phosphate-related cytotoxicity of the Huh7 and HLF cell lines. In vivo tests were conducted to investigate the tumorigenicity of HCC cells xenografted into immunocompromised mice after silencing XPR1. Compared with that in paracancerous tissue, XPR1 expression in HCC tissues was markedly upregulated. High XPR1 expression significantly correlated with poor patient survival. Silencing of XPR1 leads to decreased proliferation, migration, invasion, and colony formation in HCC cells. Mechanistically, knockdown of XPR1 causes an increase in intracellular phosphate levels; mitochondrial dysfunction characterized by reduced mitochondrial membrane potential and adenosine triphosphate levels; increased reactive oxygen species levels; abnormal mitochondrial morphology; and downregulation of key mitochondrial fusion, fission, and inner membrane genes. This ultimately results in mitochondria-dependent apoptosis. These findings reveal the prognostic value of XPR1 in HCC progression and, more importantly, suggest that XPR1 might be a potential therapeutic target.

7.
Cytokine ; 173: 156423, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37979212

RESUMO

Isthmin is a polypeptide secreted by adipocytes that was first detected in Xenopus gastrula embryos. Recent studies have focused on the biological functions of isthmin in growth and development, angiogenesis, and metabolism. Distinct spatiotemporal expression of isthmin-1 (ISM-1) was observed during growth and development. ISM-1 plays an important role in the occurrence and development of cancer by regulating cell proliferation, migration, angiogenesis, and immune microenvironments. Moreover, ISM-1, as a newly identified insulin-like adipokine, increases adipocyte glucose uptake and inhibits hepatic lipid synthesis. However, the biological function of ISM-1 remains largely unknown. In this review, we highlight the structure and physiological functions of isthmin and explore its application potential, contributing to a better understanding of its function and providing prevention and treatment strategies for various diseases.


Assuntos
Trombospondinas , Proliferação de Células , Glucose , Insulina , Fígado/metabolismo , Humanos , Animais , Trombospondinas/fisiologia
8.
Arch Microbiol ; 206(7): 289, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847838

RESUMO

Staphylococcus epidermidis is an opportunistic pathogen commonly implicated in medical device-related infections. Its propensity to form biofilms not only leads to chronic infections but also exacerbates the issue of antibiotic resistance, necessitating high-dose antimicrobial treatments. In this study, we explored the use of diclofenac sodium, a non-steroidal anti-inflammatory drug, as an anti-biofilm agent against S. epidermidis. In this study, crystal violet staining and confocal laser scanning microscope analysis showed that diclofenac sodium, at subinhibitory concentration (0.4 mM), significantly inhibited biofilm formation in both methicillin-susceptible and methicillin-resistant S. epidermidis isolates. MTT assays demonstrated that 0.4 mM diclofenac sodium reduced the metabolic activity of biofilms by 25.21-49.01% compared to untreated controls. Additionally, the treatment of diclofenac sodium resulted in a significant decrease (56.01-65.67%) in initial bacterial adhesion, a crucial early phase of biofilm development. Notably, diclofenac sodium decreased the production of polysaccharide intercellular adhesin (PIA), a key component of the S. epidermidis biofilm matrix, in a dose-dependent manner. Real-time quantitative PCR analysis revealed that diclofenac sodium treatment downregulated biofilm-associated genes icaA, fnbA, and sigB and upregulated negative regulatory genes icaR and luxS, providing potential mechanistic insights. These findings indicate that diclofenac sodium inhibits S. epidermidis biofilm formation by affecting initial bacterial adhesion and the PIA synthesis. This underscores the potential of diclofenac sodium as a supplementary antimicrobial agent in combating staphylococcal biofilm-associated infections.


Assuntos
Antibacterianos , Biofilmes , Diclofenaco , Staphylococcus epidermidis , Biofilmes/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/fisiologia , Diclofenaco/farmacologia , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Anti-Inflamatórios não Esteroides/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Humanos , Polissacarídeos Bacterianos/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos
9.
Arch Microbiol ; 206(10): 401, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39261350

RESUMO

Staphylococcus aureus is a notorious pathogen predominantly involved in skin and soft tissue infections, exhibiting a distinct innate sex bias. This study explores the influence of testosterone on the virulence of S. aureus and elucidates its underlying mechanisms. Utilizing a skin abscess model in intact and castrated male mice, we assessed the effects of testosterone on S. aureus pathogenicity. Compared to controls, castrated mice showed significantly reduced abscess sizes and decreased bacterial loads, highlighting the role of testosterone in modulating the severity of S. aureus infections. In vitro experiments revealed that testosterone enhances the hemolytic activity, cytotoxicity, and oxidative stress resistance of S. aureus. Real-time quantitative PCR analysis showed a significant upregulation of the genes encoding α-hemolysin (hla) and phenol-soluble modulin (psmα). Importantly, testosterone treatment significantly enhanced the expression of the accessory gene regulator (Agr) quorum-sensing system components (agrC, agrA, agrB, agrD), while the SaeRS system (saeR, saeS, and sbi) exhibited only slight changes. Gene knockout experiments revealed that deletion of agrC, rather than saeRS and agrBD, abolishes the testosterone-induced enhancement of hemolysis and gene expression, underscoring the key role of AgrC. Molecular docking simulations indicated a direct interaction between testosterone and AgrC protein, with a strong binding affinity at the active site residue SER201. This study provides new insights into the mechanistic basis of how testosterone enhances the pathogenicity of S. aureus, potentially contributing to increased male susceptibility to S. aureus infections and offering a targeted approach for therapeutic interventions.


Assuntos
Proteínas de Bactérias , Infecções Estafilocócicas , Staphylococcus aureus , Testosterona , Masculino , Testosterona/farmacologia , Testosterona/metabolismo , Animais , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidade , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/metabolismo , Camundongos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Virulência , Infecções Estafilocócicas/microbiologia , Transativadores/genética , Transativadores/metabolismo , Regulação Bacteriana da Expressão Gênica , Percepção de Quorum , Simulação de Acoplamento Molecular , Toxinas Bacterianas/metabolismo , Toxinas Bacterianas/genética , Abscesso/microbiologia , Hemólise , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/genética
10.
J Org Chem ; 89(5): 3471-3480, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38350101

RESUMO

A Pd-catalyzed thiocarbonylative cyclization of N-(o-iodoaryl)acrylamides with easily accessible thioformates has been developed. The reaction has a wide substrate scope with good yields and represents a powerful route to the synthesis of thioester-functionalized oxindoles. Both S-aryl and alkyl thioformates as the thioester sources were well tolerated. The active Pd-CO intermediate may play an important role in the transformation process.

11.
Org Biomol Chem ; 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39453406

RESUMO

A palladium-catalyzed cascade reaction of α,ß-unsaturated N-tosylhydrazones with iodoarene derivatives containing a nucleophilic group has been developed, which provides facile access to 2H-chromenes and 2H-quinolines, respectively. Additionally, the double Pd-carbene migratory insertion/nucleophilic substitution processes for the synthesis of a ternary heterocyclic skeleton were possible in the developed catalytic system.

12.
Org Biomol Chem ; 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39402895

RESUMO

Four previously undescribed heterodimeric diketopiperazine alkaloids, expansines A-D, were identified from the solid rice medium fermented by Penicillium expansum MA147, along with one new resorcylic acid derivative and five known compounds. Their structures and relative/absolute configurations were elucidated by interpretation of their spectroscopic data, quantum chemical calculations, and chemical conversion. Some obtained compounds were evaluated for the cytotoxicity against a triple-negative breast cancer cell line MDA-MB-231, and expansine C showed an IC50 value of 3.23 µM. In further mechanistic studies, we found that it might act by increasing the expression of ATP-binding cassette transporter A1 and reducing cellular cholesterol levels, suggesting its potential as a novel anti-cancer agent.

13.
J Nat Prod ; 87(4): 743-752, 2024 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-38359467

RESUMO

Nuclear magnetic resonance (NMR) chemical shift calculations are powerful tools for structure elucidation and have been extensively employed in both natural product and synthetic chemistry. However, density functional theory (DFT) NMR chemical shift calculations are usually time-consuming, while fast data-driven methods often lack reliability, making it challenging to apply them to computationally intensive tasks with a high requirement on quality. Herein, we have constructed a 54-layer-deep graph convolutional network for 13C NMR chemical shift calculations, which achieved high accuracy with low time-cost and performed competitively with DFT NMR chemical shift calculations on structure assignment benchmarks. Our model utilizes a semiempirical method, GFN2-xTB, and is compatible with a broad variety of organic systems, including those composed of hundreds of atoms or elements ranging from H to Rn. We used this model to resolve the controversial J/K ring junction problem of maitotoxin, which is the largest whole molecule assigned by NMR calculations to date. This model has been developed into user-friendly software, providing a useful tool for routine rapid structure validation and assignation as well as a new approach to elucidate the large structures that were previously unsuitable for NMR calculations.


Assuntos
Teoria da Densidade Funcional , Estrutura Molecular , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13/métodos , Oxocinas/química , Software
14.
Acta Pharmacol Sin ; 45(6): 1214-1223, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38467718

RESUMO

CD80 is a transmembrane glycoprotein belonging to the B7 family, which has emerged as a crucial molecule in T cell modulation via the CD28 or CTLA4 axes. CD80-involved regulation of immune balance is a finely tuned process and it is important to elucidate the underlying mechanism for regulating CD80 function. In this study we investigated the post-translational modification of CD80 and its biological relevance. By using a metabolic labeling strategy, we found that CD80 was S-palmitoylated on multiple cysteine residues (Cys261/262/266/271) in both the transmembrane and the cytoplasmic regions. We further identified zDHHC20 as a bona fide palmitoyl-transferase determining the S-palmitoylation level of CD80. We demonstrated that S-palmitoylation protected CD80 protein from ubiquitination degradation, regulating the protein stability, and ensured its accurate plasma membrane localization. The palmitoylation-deficient mutant (4CS) CD80 disrupted these functions, ultimately resulting in the loss of its costimulatory function upon T cell activation. Taken together, our results describe a new post-translational modification of CD80 by S-palmitoylation as a novel mechanism for the regulation of CD80 upon T cell activation.


Assuntos
Aciltransferases , Antígeno B7-1 , Lipoilação , Ativação Linfocitária , Humanos , Antígeno B7-1/metabolismo , Aciltransferases/metabolismo , Células HEK293 , Linfócitos T/metabolismo , Linfócitos T/imunologia , Processamento de Proteína Pós-Traducional , Ubiquitinação
15.
Dig Dis Sci ; 69(5): 1583-1592, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38526618

RESUMO

Colorectal cancer (CRC) is a common malignant tumor of the gastrointestinal tract with increasing morbidity and mortality. Exploring the factors affecting colorectal carcinogenesis and controlling its occurrence at its root is as important as studying post-cancer treatment and management. Establishing ideal animal models of CRC is crucial, which can occur through various pathways, such as adenoma-carcinoma sequence, inflammation-induced carcinogenesis, serrated polyp pathway and de-novo pathway. This article aims to categorize the existing well-established CRC animal models based on different carcinogenesis pathways, and to describe their mechanisms, methods, advantages and limitations using domestic and international literature sources. This will provide suggestions for the selection of animal models in early-stage CRC research.


Assuntos
Carcinogênese , Neoplasias Colorretais , Modelos Animais de Doenças , Animais , Neoplasias Colorretais/patologia , Neoplasias Colorretais/etiologia , Carcinogênese/patologia , Humanos , Camundongos , Adenoma/patologia
16.
Lipids Health Dis ; 23(1): 127, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38685122

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD), often linked with obesity, can also affect individuals with normal weight, a condition known as "lean NAFLD", imposing comparable burdens and adverse effects. However, the impact of diet on lean NAFLD remains underexplored. The objective of this study is to investigate the correlation between the Dietary Inflammatory Index (DII) and NAFLD among Americans, stratified by waist-to-height ratio (WHtR) and body mass index (BMI). METHODS: Five thousand one hundred fifty-two participants from the National Health and Nutrition Examination Survey (NHANES) 2003-2018 were comprised in the final analysis. NAFLD and advanced liver fibrosis were diagnosed by serological markers. Lean and abdominal lean individuals were identified using BMI and WHtR, separately. DII was determined by assigning scores to 28 distinct food parameters based on their inflammatory potential, obtained from the NAHNES website. Differences across DII quartiles were evaluated using the Kruskal-Wallis H Test, Chi-Square Test along with One-Way ANOVA. The correlation between DII and NAFLD was determined by multiple regression models and subgroup analyses. RESULTS: Among the 5152 subjects, 2503 were diagnosed with NAFLD, including 86 cases of lean NAFLD and 8 cases of abdominal lean NAFLD. DII was positively linked with NAFLD (Odds Ratio (OR) = 1.81 [1.48-2.21], P < 0.001) and advanced liver fibrosis (OR = 1.46 [1.02-2.07], P = 0.037). Further analysis revealed that this association was primarily observed in obese or abdominal obese participants (In BMI ≥ 25.00 kg/m^2, OR = 1.56 [1.23-1.98], P < 0.001. In WHtR> 0.50, OR = 1.48 [1.23-1.79], P < 0.001.), rather than their lean counterparts. Subgroup analyses indicated that female individuals, without a diagnosis of hypertension or diabetes appeared to be more sensitive to the rise in DII. CONCLUSIONS: Our data demonstrated a significant positive correlation between DII and NAFLD in the general population. However, the impact of a pro-inflammatory diet was less prominent in lean individuals compared to obese ones.


Assuntos
Índice de Massa Corporal , Inflamação , Hepatopatia Gordurosa não Alcoólica , Inquéritos Nutricionais , Obesidade , Humanos , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/complicações , Feminino , Masculino , Obesidade/complicações , Pessoa de Meia-Idade , Adulto , Dieta/efeitos adversos , Razão Cintura-Estatura , Magreza/complicações , Fatores de Risco , Cirrose Hepática/patologia , Cirrose Hepática/epidemiologia
17.
Nucleic Acids Res ; 50(10): 5726-5738, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35640616

RESUMO

The structure and properties of DNA depend on the environment, in particular the ion atmosphere. Here, we investigate how DNA twist -one of the central properties of DNA- changes with concentration and identity of the surrounding ions. To resolve how cations influence the twist, we combine single-molecule magnetic tweezer experiments and extensive all-atom molecular dynamics simulations. Two interconnected trends are observed for monovalent alkali and divalent alkaline earth cations. First, DNA twist increases monotonously with increasing concentration for all ions investigated. Second, for a given salt concentration, DNA twist strongly depends on cation identity. At 100 mM concentration, DNA twist increases as Na+ < K+ < Rb+ < Ba2+ < Li+ ≈ Cs+ < Sr2+ < Mg2+ < Ca2+. Our molecular dynamics simulations reveal that preferential binding of the cations to the DNA backbone or the nucleobases has opposing effects on DNA twist and provides the microscopic explanation of the observed ion specificity. However, the simulations also reveal shortcomings of existing force field parameters for Cs+ and Sr2+. The comprehensive view gained from our combined approach provides a foundation for understanding and predicting cation-induced structural changes both in nature and in DNA nanotechnology.


Assuntos
DNA , Simulação de Dinâmica Molecular , Cátions , Cátions Bivalentes , Cátions Monovalentes , DNA/química , Sódio , Cloreto de Sódio
18.
J Formos Med Assoc ; 123(3): 325-330, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38097427

RESUMO

AIMS: Advanced maternal age (AMA) is correlated with higher risk of adverse pregnancy outcomes while the pathophysiology remains unclear. Our study aimed to investigate whether AMA is linked to the clustering of metabolic abnormalities, which in turn is associated with an increased risk of adverse pregnancy outcomes. METHOD: A total of 857 pregnant woman were recruited in a prospective cohort at National Taiwan University Hospital, from November 2013 to April 2018. Metabolic abnormalities during pregnancy were defined as following: fasting plasma glucose ≥92 mg/dl, body mass index (BMI) ≥24 kg/m2, plasma high-density lipoprotein cholesterol <50 mg/dl, hyper-triglyceridemia (≥140 mg/dl in the first trimester or ≥220 mg/dl in the second trimester), and blood pressure ≥130/85 mmHg. RESULT: Incidence of large for gestational age (LGA), primary caesarean section (CS), and the presence of any adverse pregnancy outcome increased with age. The advanced-age group tended to have more metabolic abnormalities in both the first and the second trimesters. There was a significant association between the number of metabolic abnormalities in the first and the second trimesters and the incidence of LGA, gestational hypertension or preeclampsia, primary CS, preterm birth, and the presence of any adverse pregnancy outcome, adjusted for maternal age. CONCLUSION: AMA is associated with clustering of metabolic abnormalities during pregnancy, and clustering of metabolic abnormalities is correlated with increased risk of adverse pregnancy outcomes.


Assuntos
Resultado da Gravidez , Nascimento Prematuro , Gravidez , Recém-Nascido , Humanos , Feminino , Resultado da Gravidez/epidemiologia , Estudos Prospectivos , Idade Materna , Cesárea , Nascimento Prematuro/epidemiologia
19.
Chin J Traumatol ; 27(5): 305-310, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38641468

RESUMO

PURPOSE: Intramedullary nailing is the preferred internal fixation technique for the treatment of subtrochanteric fractures because of its biomechanical advantages. However, no definitive conclusion has been reached regarding whether combined cable cerclage is required during intramedullary nailing treatment. This study is performed to compare the clinical effects of intramedullary nailing with cerclage and non-cerclage wiring in the treatment of irreducible spiral subtrochanteric fractures. METHODS: Patients with subtrochanteric fractures admitted to our center from January 2013 to December 2021 were retrospectively analyzed. The patients were enrolled in the case-control study according to the inclusion and exclusion criteria and divided into the non-cerclage group and the cerclage group. The patients' clinical data, including the operative time, intraoperative blood loss, hospital stay, reoperation rate, fracture union time, and Harris hip score, were compared between these 2 groups. Categorical variables were compared using Chi-square or Fisher's exact test. Continuous variables with normal distribution were presented as mean ± standard deviation and analyzed with Student's t-test. Non-normally distributed variables were expressed as median (Q1, Q3) and assessed using the Mann-Whitney test. A p < 0.05 was considered significant. RESULTS: In total, 69 patients were included in the study (35 patients in the non-cerclage group and 34 patients in the cerclage group). The baseline data of the 2 groups were comparable. There were no significant difference in the length of hospital stay (z = -0.391, p = 0.696), operative time (z = -1.289, p = 0.197), or intraoperative blood loss (z = -1.321, p = 0.186). However, compared with non-cerclage group, the fracture union time was shorter (z = -5.587, p < 0.001), the rate of nonunion was lower (χ2 = 6.030, p = 0.03), the anatomical reduction rate was higher (χ2 = 5.449, p = 0.03), and the Harris hip score was higher (z = -2.99, p = 0.003) in the cerclage group, all with statistically significant differences. CONCLUSIONS: Intramedullary nailing combined with cable cerclage wiring is a safe and reliable technique for the treatment of irreducible subtrochanteric fractures. This technique can improve the reduction effect, increase the stability of fracture fixation, shorten the fracture union time, reduce the occurrence of nonunion, and contribute to the recovery of hip joint function.


Assuntos
Fixação Intramedular de Fraturas , Fraturas do Quadril , Humanos , Fraturas do Quadril/cirurgia , Fixação Intramedular de Fraturas/métodos , Fixação Intramedular de Fraturas/instrumentação , Feminino , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Estudos de Casos e Controles , Idoso , Adulto , Fios Ortopédicos , Tempo de Internação/estatística & dados numéricos , Duração da Cirurgia , Resultado do Tratamento
20.
J Transl Med ; 21(1): 919, 2023 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-38110956

RESUMO

BACKGROUND: Mutations in TP53 gene is considered a main driver of hepatocellular carcinoma (HCC). While TP53 mutations are the leading cause of p53 dysfunction, their occurrence rates may drop to approximately 10% in cohorts without hepatitis B virus and aflatoxin exposure. This observation suggests that the deactivation of wild-type p53 (p53wt) may be a critical factor in the majority of HCC cases. However, the mechanism undermining p53wt activity in the liver remains unclear. METHODS: Microarray analysis and luciferase assay were utilized to confirm target associations. Gain- and/or loss-of-function methods were employed to assess alterations in signaling pathways. Protein interactions were analyzed by molecular immunological methods and further visualized by confocal microscopy. Bioinformatic analysis was performed to analyze clinical significance. Tumor xenograft nude mice were used to validate the findings in vivo. RESULTS: Our study highlights the oncogenic role of Rictor, a key component of the mammalian target of rapamycin complex 2 (mTORC2), in hepatocytes. Rictor exerts its oncogenic function by binding to p53wt and subsequently blocking p53wt activity based on p53 status, requiring the involvement of mTOR. Moreover, we observed a dynamic nucleocytoplasmic distribution pattern of Rictor, characterized by its translocation from the nucleus (in precancerous lesions) to the cytoplasm (in HCCs) during malignant transformation. Notably, Rictor is directly targeted by the liver-enriched microRNA miR-192, and the disruption of the miR-192-Rictor-p53-miR-192 signaling axis was consistently observed in both human and rat HCC models. Clinical analysis associated lower miR-192/higher Rictor with shorter overall survival and more advanced clinical stages (P < 0.05). In mice, xenograft tumors overexpressing miR-192 exhibited lower Rictor expression levels, leading to higher p53 activity, and these tumors displayed slower growth compared to untreated HCC cells. CONCLUSIONS: Rictor dynamically shuttles between the nucleus and cytoplasm during HCC development. Its pivotal oncogenic role involves binding and inhibiting p53wt activity within the nucleus in early hepatocarcinogenesis. Targeting Rictor presents a promising strategy for HCC based on p53 status.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Proteína Companheira de mTOR Insensível à Rapamicina , Animais , Humanos , Camundongos , Ratos , Carcinogênese/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Regulação Neoplásica da Expressão Gênica , Genes p53 , Hepatócitos/patologia , Neoplasias Hepáticas/patologia , Camundongos Nus , MicroRNAs/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteína Companheira de mTOR Insensível à Rapamicina/metabolismo
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