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1.
World J Microbiol Biotechnol ; 40(9): 265, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38990361

RESUMEN

The increasing prevalence of infections related to methicillin-resistant Staphylococcus aureus (MRSA) necessitates the exploration of innovative therapeutic strategies that diverge from conventional antibiotic treatments. This is imperative to effectively combat resistance and manage these infections. The adoption of antivirulence strategies has emerged as a particularly promising avenue. This approach applies a heightened selective pressure on pathogens, thereby diminishing the likelihood of bacteria evolving resistance to antibiotics. In our pursuit of novel therapeutics for treating MRSA infections, we have focused on agents that inhibit the virulence of S. aureus without impeding its growth, aiming to minimize the development of drug resistance. α-Hemolysin, a critical virulence factor encoded by the hla gene, is a cytotoxin that forms pores in host cell membranes and plays a pivotal role in the progression of disease during bacterial infections. Herein, we identified that norwogonin could effectively inhibit Hla production via targeting agrAC, a crucial protein in quorum sensing, resulting in dose-dependent inhibition of hemolytic activity without suppressing S. aureus growth. In vitro assays illustrated that norwogonin decreased the thermal stability of agrAC, providing evidence of interaction between norwogonin and agrAC. Meanwhile, norwogonin alleviated Hla-mediated A549 cell damage and reduced lactate dehydrogenase release. In vivo studies suggested that norwogonin treatment blocked the establishment of a mouse model of pneumonia caused by S. aureus USA300. Notably, norwogonin enhanced the antibacterial potency of oxacillin. In conclusion, norwogonin is a promising candidate for treating S. aureus infections, offering a novel alternative to traditional antibiotics by targeting virulence factors and enhancing the efficacy of existing treatments.


Asunto(s)
Antibacterianos , Proteínas Bacterianas , Proteínas Hemolisinas , Staphylococcus aureus Resistente a Meticilina , Factores de Virulencia , Animales , Femenino , Humanos , Ratones , Células A549 , Antibacterianos/farmacología , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Modelos Animales de Enfermedad , Proteínas Hemolisinas/metabolismo , Hemólisis/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Ratones Endogámicos BALB C , Percepción de Quorum/efectos de los fármacos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Virulencia/efectos de los fármacos , Factores de Virulencia/metabolismo
2.
J Nanobiotechnology ; 22(1): 392, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38965606

RESUMEN

Pancreatic cancer, predominantly pancreatic ductal adenocarcinoma (PDAC), remains a highly lethal malignancy with limited therapeutic options and a dismal prognosis. By targeting the underlying molecular abnormalities responsible for PDAC development and progression, gene therapy offers a promising strategy to overcome the challenges posed by conventional radiotherapy and chemotherapy. This study sought to explore the therapeutic potential of small activating RNAs (saRNAs) specifically targeting the CCAAT/enhancer-binding protein alpha (CEBPA) gene in PDAC. To overcome the challenges associated with saRNA delivery, tetrahedral framework nucleic acids (tFNAs) were rationally engineered as nanocarriers. These tFNAs were further functionalized with a truncated transferrin receptor aptamer (tTR14) to enhance targeting specificity for PDAC cells. The constructed tFNA-based saRNA formulation demonstrated exceptional stability, efficient saRNA release ability, substantial cellular uptake, biocompatibility, and nontoxicity. In vitro experiments revealed successful intracellular delivery of CEBPA-saRNA utilizing tTR14-decorated tFNA nanocarriers, resulting in significant activation of tumor suppressor genes, namely, CEBPA and its downstream effector P21, leading to notable inhibition of PDAC cell proliferation. Moreover, in a mouse model of PDAC, the tTR14-decorated tFNA-mediated delivery of CEBPA-saRNA effectively upregulated the expression of the CEBPA and P21 genes, consequently suppressing tumor growth. These compelling findings highlight the potential utility of saRNA delivered via a designed tFNA nanocarrier to induce the activation of tumor suppressor genes as an innovative therapeutic approach for PDAC.


Asunto(s)
Aptámeros de Nucleótidos , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Receptores de Transferrina , Animales , Humanos , Neoplasias Pancreáticas/tratamiento farmacológico , Carcinoma Ductal Pancreático/tratamiento farmacológico , Aptámeros de Nucleótidos/química , Aptámeros de Nucleótidos/farmacología , Receptores de Transferrina/metabolismo , Ratones , Línea Celular Tumoral , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Proteínas Potenciadoras de Unión a CCAAT/genética , Proliferación Celular/efectos de los fármacos , Terapia Genética/métodos , ARN Interferente Pequeño/farmacología , Ratones Desnudos
3.
Cancer Med ; 13(12): e7439, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38924382

RESUMEN

BACKGROUND: Patients diagnosed with advanced stage cancer face an elevated risk of suicide. We aimed to develop a suicidal ideation (SI) risk prediction model in patients with advanced cancer for early warning of their SI and facilitate suicide prevention in this population. PATIENTS AND METHODS: We consecutively enrolled patients with multiple types of advanced cancers from 10 cancer institutes in China from August 2019 to December 2020. Demographic characteristics, clinicopathological data, and clinical treatment history were extracted from medical records. Symptom burden, psychological status, and SI were assessed using the MD Anderson Symptom Inventory (MDASI), Hospital Anxiety and Depression Scale (HADS), and Patient Health Questionnaire-9 (PHQ-9), respectively. A multivariable logistic regression model was employed to establish the model structure. RESULTS: In total, 2814 participants were included in the final analysis. Nine predictors including age, sex, number of household members, history of previous chemotherapy, history of previous surgery, MDASI score, HADS-A score, HADS-D score, and life satisfaction were retained in the final SI prediction model. The model achieved an area under the curve (AUC) of 0.85 (95% confidential interval: 0.82-0.87), with AUCs ranging from 0.75 to 0.95 across 10 hospitals and higher than 0.83 for all cancer types. CONCLUSION: This study built an easy-to-use, good-performance predictive model for SI. Implementation of this model could facilitate the incorporation of psychosocial support for suicide prevention into the standard care of patients with advanced cancer.


Asunto(s)
Neoplasias , Ideación Suicida , Humanos , Masculino , Femenino , Neoplasias/psicología , China/epidemiología , Persona de Mediana Edad , Anciano , Medición de Riesgo , Adulto , Factores de Riesgo
4.
Cancer Med ; 13(11): e7330, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38845478

RESUMEN

OBJECTIVES: Patients with advanced colorectal cancer (CRC) have multiple concurrent physical and psychological symptoms. This study aimed to explore the relationship between anxiety, depression, and symptom burden in advanced CRC. METHODS: A multicenter cross-sectional study was conducted in 10 cancer centers from geographically and economically diverse sites in China. A total of 454 patients with advanced CRC completed the Hospital Anxiety and Depression Scale and the MD Anderson Symptom Inventory. Multiple regression analysis was applied to explore the relationship between anxiety, depression and symptom burden. RESULTS: About one-third of the patients showed symptoms of anxiety or depression. Patients with anxiety or depression reported significantly higher symptom burden than those without (p < 0.001). Patients with anxiety or depression reported a higher proportion of moderate-to-severe (MS) symptom number than those without (p < 0.001). About 52% of the patients with anxiety or depression reported at least three MS symptoms. The prevalence of MS symptoms was ranging from 7.3% (shortness of breath) to 22% (disturbed sleep), and in patients with anxiety or depression was 2-10 times higher than in those without (p < 0.001). Disease stage (ß = -2.55, p = 0.003), anxiety (ß = 15.33, p < 0.001), and depression (ß = 13.63, p < 0.001) were associated with higher symptom burden. CONCLUSIONS: Anxiety and depression in patients with advanced cancer correlated with higher symptom burden. Findings may lead oncology professionals to pay more attention to unrecognized and untreated psychological symptoms in symptom management for advanced cancer patients.


Asunto(s)
Ansiedad , Neoplasias Colorrectales , Depresión , Humanos , Neoplasias Colorrectales/psicología , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/complicaciones , Masculino , Femenino , Estudios Transversales , Persona de Mediana Edad , Depresión/epidemiología , Depresión/etiología , Depresión/psicología , Ansiedad/epidemiología , Ansiedad/psicología , Anciano , China/epidemiología , Prevalencia , Adulto , Anciano de 80 o más Años , Calidad de Vida , Carga Sintomática
5.
Appl Microbiol Biotechnol ; 108(1): 360, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38836914

RESUMEN

In the fight against hospital-acquired infections, the challenge posed by methicillin-resistant Staphylococcus aureus (MRSA) necessitates the development of novel treatment methods. This study focused on undermining the virulence of S. aureus, especially by targeting surface proteins crucial for bacterial adherence and evasion of the immune system. A primary aspect of our approach involves inhibiting sortase A (SrtA), a vital enzyme for attaching microbial surface components recognizing adhesive matrix molecules (MSCRAMMs) to the bacterial cell wall, thereby reducing the pathogenicity of S. aureus. Verbascoside, a phenylethanoid glycoside, was found to be an effective SrtA inhibitor in our research. Advanced fluorescence quenching and molecular docking studies revealed a specific interaction between verbascoside and SrtA, pinpointing the critical active sites involved in this interaction. This molecular interaction significantly impedes the SrtA-mediated attachment of MSCRAMMs, resulting in a substantial reduction in bacterial adhesion, invasion, and biofilm formation. The effectiveness of verbascoside has also been demonstrated in vivo, as shown by its considerable protective effects on pneumonia and Galleria mellonella (wax moth) infection models. These findings underscore the potential of verbascoside as a promising component in new antivirulence therapies for S. aureus infections. By targeting crucial virulence factors such as SrtA, agents such as verbascoside constitute a strategic and potent approach for tackling antibiotic resistance worldwide. KEY POINTS: • Verbascoside inhibits SrtA, reducing S. aureus adhesion and biofilm formation. • In vivo studies demonstrated the efficacy of verbascoside against S. aureus infections. • Targeting virulence factors such as SrtA offers new avenues against antibiotic resistance.


Asunto(s)
Aminoaciltransferasas , Antibacterianos , Adhesión Bacteriana , Proteínas Bacterianas , Biopelículas , Cisteína Endopeptidasas , Glucósidos , Staphylococcus aureus Resistente a Meticilina , Simulación del Acoplamiento Molecular , Fenoles , Infecciones Estafilocócicas , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/antagonistas & inhibidores , Aminoaciltransferasas/antagonistas & inhibidores , Aminoaciltransferasas/metabolismo , Cisteína Endopeptidasas/metabolismo , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/patogenicidad , Glucósidos/farmacología , Animales , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Fenoles/farmacología , Adhesión Bacteriana/efectos de los fármacos , Biopelículas/efectos de los fármacos , Antibacterianos/farmacología , Mariposas Nocturnas/microbiología , Virulencia/efectos de los fármacos , Modelos Animales de Enfermedad , Factores de Virulencia/metabolismo , Inhibidores Enzimáticos/farmacología , Polifenoles
6.
BMC Psychol ; 12(1): 139, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38475847

RESUMEN

PURPOSE: The pathways underpinning suicide ideation (SI) and certain physical and psychological factors in patients with advanced breast cancer remain unclear. This study develops and validates a mediation model that delineates the associations between several multidimensional variables and SI in Chinese patients with advanced breast cancer. METHODS: Patients with advanced breast cancer (n = 509) were recruited as study participants from 10 regional cancer centers across China from August 2019 to December 2020. Participants were required to complete five questionnaires using an electronic patient-reported outcomes (ePRO) system: 9 item- Patient Health Questionnaire (PHQ-9), Hospital Anxiety and Depression Scale (HADS), Insomnia Severity Index (ISI), 5-level EQ-5D (EQ-5D-5L), and MD Anderson Symptom Inventory (MDASI). Risk factors for SI were identified using multivariable logistic regression, and inputted into serial multiple mediation models to elucidate the pathways linking the risk factors to SI. RESULTS: SI prevalence was 22.8% (116/509). After adjusting for covariates, depression (odds ratio [OR] = 1.384), emotional distress (OR = 1.107), upset (OR = 0.842), and forgetfulness (OR = 1.236) were identified as significant independent risk factors (all p < 0.05). The ORs indicate that depression and distress have the strongest associations with SI. Health status has a significant indirect effect (OR=-0.044, p = 0.005) and a strong total effect (OR=-0.485, p < 0.001) on SI, mediated by insomnia severity and emotional distress. CONCLUSIONS: There is a high SI prevalence among Chinese patients with advanced breast cancer. Our analysis revealed predictive pathways from poor health to heightened SI, mediated by emotional distress and insomnia. Regular management of distress and insomnia can decrease suicide risk in this vulnerable population.


Asunto(s)
Neoplasias de la Mama , Trastornos del Inicio y del Mantenimiento del Sueño , Humanos , Femenino , Ideación Suicida , Depresión/psicología , Factores de Riesgo
7.
NPJ Biofilms Microbiomes ; 10(1): 15, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38413623

RESUMEN

Limitations in the clinical treatment of Staphylococcus aureus (S. aureus) infections have arisen due to the advent of antibiotic-resistant strains. Given the immense potential of therapeutic strategies targeting bacterial virulence, the role of MgrA as a pivotal virulence determinant in S. aureus-orchestrating resistance, adherence, and hundreds of virulence targets-becomes indispensable. In this investigation, leveraging advanced virtual screening and fluorescence anisotropy assays, we discerned methylophiopogonanone A (Mo-A), a flavonoid derivative, as a potent disruptor of the MgrA-DNA interaction nexus. Subsequent analysis revealed that Mo-A effectively inhibits the expression of virulence factors such as Hla and Pvl in S. aureus and markedly reduces its adhesion capability to fibrinogen. On a cellular landscape, Mo-A exerts a mitigating influence on the deleterious effects inflicted by S. aureus USA300 on A549 cells. Furthermore, our data indicate that Mo-A downregulates the transcription of genes associated with immune evasion, such as nucleases (nuc), Staphylococcal Chemotaxis Inhibitory Protein (chips), and Staphylococcal Complement Inhibitor (scin), thereby undermining immune escape and amplifying neutrophil chemotaxis. Upon application in an in vivo setting, Mo-A assumes a protective persona in a murine model of S. aureus USA300-induced pneumonia and demonstrates efficacy in the Galleria mellonella infection model. Of note, S. aureus displayed no swift acquisition of resistance to Mo-A, and the effect was synergistically enhanced when used in combination with vancomycin. Our findings add substantive weight to the expanding field of virulence-targeted therapeutic strategies and set the stage for more comprehensive exploration of Mo-A potential in combating antibiotic-resistant S. aureus.


Asunto(s)
Benzodioxoles , Isoflavonas , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Ratones , Animales , Staphylococcus aureus/genética , Proteínas Bacterianas/genética , Factores de Virulencia/genética , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Antibacterianos/metabolismo
8.
BMC Geriatr ; 24(1): 185, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38395756

RESUMEN

BACKGROUND: Little is understood about the association between psychosomatic symptoms and advanced cancer among older Chinese patients. METHODS: This secondary analysis was part of a multicenter cross-sectional study based on an electronic patient-reported outcome platform. Patients with advanced cancer were included between August 2019 and December 2020 in China. Participants (over 60 years) completed the MD Anderson Symptom Inventory (MDASI) and Hospital Anxiety and Depression Scale (HADS) to measure symptom burden. Network analysis was also conducted to investigate the network structure, centrality indices (strength, closeness, and betweenness) and network stability. RESULTS: A total of 1022 patients with a mean age of 66 (60-88) years were included; 727 (71.1%) were males, and 295 (28.9%) were females. A total of 64.9% of older patients with advanced cancer had one or more symptoms, and up to 80% had anxiety and depression. The generated network indicated that the physical symptoms, anxiety and depression symptom communities were well connected with each other. Based on an evaluation of the centrality indices, 'distress/feeling upset' (MDASI 5) appears to be a structurally important node in all three networks, and 'I lost interest in my own appearance' (HADS-D4) had the lowest centrality indices. The network stability was relatively high (> 0.7). CONCLUSION: The symptom burden remains high in older patients with advanced cancer in China. Psychosomatic symptoms are highly interactive and often present as comorbidities. This network can be used to provide targeted interventions to optimize symptom management in older patients with advanced cancer in China. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR1900024957), registered on 06/12/2020.


Asunto(s)
Depresión , Neoplasias , Masculino , Femenino , Humanos , Anciano , Depresión/diagnóstico , Depresión/epidemiología , Estudios Transversales , Ansiedad/diagnóstico , Ansiedad/epidemiología , Neoplasias/complicaciones , Neoplasias/diagnóstico , Neoplasias/epidemiología , Trastornos de Ansiedad
10.
Med Microbiol Immunol ; 212(6): 421-435, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37796314

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) is a pathogenic bacterium responsible for a range of severe infections, such as skin infections, bacteremia, and pneumonia. Due to its antibiotic-resistant nature, current research focuses on targeting its virulence factors. Sortase A (SrtA) is a transpeptidase that anchors surface proteins to the bacterial cell wall and is involved in adhesion and invasion to host cells. Through fluorescence resonance energy transfer (FRET), we identified echinacoside (ECH), a natural polyphenol, as a potential SrtA inhibitor with an IC50 of 38.42 µM in vitro. It was demonstrated that ECH inhibited SrtA-mediated S. aureus fibrinogen binding, surface protein A anchoring, and biofilm formation. The fluorescence quenching assay determined the binding mode of ECH to SrtA and calculated the KA-binding constant of 3.09 × 105 L/mol, demonstrating the direct interaction between the two molecules. Molecular dynamics simulations revealed that ECH-SrtA interactions occurred primarily at the binding sites of A92G, A104G, V168A, G192A, and R197A. Importantly, the combination of ECH and vancomycin offered protection against murine models of MRSA-induced pneumonia. Therefore, ECH may serve as a potential antivirulence agent against S. aureus infections, either alone or in combination with vancomycin.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Neumonía , Animales , Ratones , Humanos , Staphylococcus aureus Resistente a Meticilina/metabolismo , Vancomicina/farmacología , Vancomicina/uso terapéutico , Staphylococcus aureus/metabolismo , Modelos Animales de Enfermedad , Proteínas Bacterianas/metabolismo
11.
J Appl Microbiol ; 134(10)2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37833234

RESUMEN

AIMS: Disabling bacterial virulence with small molecules has been proposed as a potential strategy to prevent bacterial pathogenicity. The von Willebrand factor-binding protein of Staphylococcus aureus was identified previously as a key virulence determinant. Our objective was to discover a von Willebrand-factor binding protein (vWbp) inhibitor distinct from the antibiotics used to prevent infections resulting from S. aureus. METHODS AND RESULTS: Using coagulation assays, we found that the sesquiterpene trilactone bilobalide blocks coagulation mediated by vWbp, but has no impact on the growth of S. aureus at a concentration of 128 µg ml-1. Moreover, a mouse model of pneumonia caused by S. aureus indicated that bilobalide could attenuate S. aureus virulence in vivo. This effect is achieved not by interfering with the expression of vWbp but by binding to vWbp, as demonstrated by western blotting, thermal shift assays, and fluorescence quenching assays. Using molecular dynamic simulations and point mutagenesis analysis, we identified that the Q17A and R453A residues are key residues for the binding of bilobalide to vWbp. CONCLUSIONS: Overall, we tested the ability of bilobalide to inhibit S. aureus infections by targeting vWbp and explored the potential mechanism of this activity.


Asunto(s)
Bilobálidos , Neumonía , Infecciones Estafilocócicas , Ratones , Animales , Proteínas Portadoras/metabolismo , Factor de von Willebrand/genética , Factor de von Willebrand/metabolismo , Staphylococcus aureus/metabolismo , Infecciones Estafilocócicas/tratamiento farmacológico
12.
ChemMedChem ; 18(22): e202300302, 2023 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-37755368

RESUMEN

The massive use of antibiotics has resulted in an alarming increase in antibiotic resistance in Staphylococcus aureus (S. aureus). This study aimed to identify the inhibitory effect of salicin on S. aureus. Coagulase (Coa) activity was assessed using in vitro Coa assays and Western blot, thermal shift assay (TSA), fluorescence quenching and molecular docking experiments were conducted to verify the interaction between salicin and Coa. An in vivo mouse pneumonia model demonstrated that salicin can reduce the virulence of S. aureus. In vitro Coa assays elucidated that salicin directly inhibited Coa activity. The Western blot and TSA results suggested that salicin did not block the expression of Coa but affected the thermal stability of the protein by binding to Coa. The fluorescence quenching, molecular docking and molecular dynamics assays have found that the most promising binding site between salicin and Coa was GLN-97. The pneumonia model of mice infected with S. aureus revealed that salicin could not only reduce the content of lung bacteria in mice but also prolong their survival. Salicin was identified as a novel anti-infective candidate compound with the potential to target Coa and inhibit its activity by binding to it, which would facilitate the development of roadmaps for future research.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Neumonía , Infecciones Estafilocócicas , Animales , Ratones , Staphylococcus aureus , Coagulasa/metabolismo , Coagulasa/farmacología , Proteínas Bacterianas , Simulación del Acoplamiento Molecular , Pruebas de Sensibilidad Microbiana , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Antibacterianos/farmacología
13.
Biochem Pharmacol ; 217: 115814, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37769713

RESUMEN

Antimicrobial resistance (AMR) is a global health threat. The dramatic increase of Methicillin-resistant Staphylococcus aureus (MRSA) infections emphasizes the need to find new anti-infective agents with a novel mode of action. The Caseinolytic protease (ClpP) is a central virulence factor in stress survival, virulence, and antibiotic resistance of MRSA. Here, we found ayanin, a flavonoid isolated from Callicarpa nudiflora, was an inhibitor of MRSA ClpP with an IC50 of 19.63 µM. Using quantitative real-time PCR, ayanin reduced the virulence of Staphylococcus aureus (S. aureus) by down-regulating the level of some important virulence factors, including agrA, RNAⅢ, hla, pvl, psmα and spa. The results of cellular thermal shift assay and thermal shift assay revealed a binding between ayanin and ClpP. Molecular docking showed that ASP-168, ASN-173 and ARG-171 were the potential binding sites for ClpP binding to ayanin. ClpP mutagenesis study further indicated that ARG-171 and ASN-173 were the main active sites of ClpP. The affinity constant (KD) value of ayanin with ClpP was 3.15 × 10-5 M measured by surface plasmon resonance. In addition, ayanin exhibited a significant therapeutic effect on pneumonia infection induced by S. aureus in mice in vivo, especially in combination with vancomycin. This is the first report of ayanin with in vivo and in vitro efficacy against S. aureus infection. In conclusion, ayanin is a promising therapeutic agent to combat MRSA infections by targeting ClpP.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Animales , Ratones , Staphylococcus aureus , Péptido Hidrolasas/farmacología , Simulación del Acoplamiento Molecular , Flavonoides/farmacología , Flavonoides/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Factores de Virulencia , Endopeptidasas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Pruebas de Sensibilidad Microbiana
14.
Future Microbiol ; 18: 735-749, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37526178

RESUMEN

Aim: Our primary objective was to investigate the protective effects and mechanisms of isovanillic acid in mice infected with Staphylococcus aureus Newman. Methods: In vitro coagulation assays were used to validate vWbp and Coa as inhibitory targets of isovanillic acid. The binding mechanism of isovanillic acid to vWbp and Coa was investigated using molecular docking and point mutagenesis. Importantly, a lethal pneumonia mouse model was used to assess the effect of isovanillic acid on survival and pathological injury in mice. Results & Conclusion: Isovanillic acid reduced the virulence of S. aureus by directly binding to inhibit the clotting activity of vWbp and Coa, thereby reducing lung histopathological damage and improving the survival rate in mice with pneumonia.


Asunto(s)
Coagulasa , Infecciones Estafilocócicas , Ratones , Animales , Coagulasa/metabolismo , Staphylococcus aureus/metabolismo , Simulación del Acoplamiento Molecular , Infecciones Estafilocócicas/prevención & control
15.
Chem Biol Interact ; 382: 110640, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37473909

RESUMEN

Diabetic kidney disease (DKD) is an essential cause of end-stage renal disease. The ongoing inflammatory response in the proximal tubule promotes the progression of DKD. Timely and effective blockade of the inflammatory process to protect the kidney during DKD progression is a proven strategy. The purpose of this study was to investigate the protective effect of loganin on diabetic nephropathy in vivo and in vitro and whether this effect was related to the inhibition of pyroptosis. The results indicated that loganin reduced fasting blood glucose, blood urea nitrogen and serum creatinine concentrations, and alleviated renal pathological changes in DKD mice. In parallel, loganin downregulated the expression of pyroptosis related proteins in the renal tubules of DKD mice and decreased serum levels of interleukin-1beta (IL-1ß) and interleukin-18 (IL-18). Furthermore, in vitro experiments showed that loganin attenuated high glucose-induced HK-2 cell injury by reducing the expression of pyroptosis-related proteins, and cytokine levels were also decreased. These fundings were also confirmed in the polyphyllin VI (PPVI) -induced HK-2 cell pyroptosis model. Loganin reduces high glucose induced HK-2 cells pyroptosis by inhibiting reactive oxygen species (ROS) production and NOD-like receptor protein 3 (NLRP3) inflammasome activation. In conclusion, the inhibition of pyroptosis via inhibition of the NLRP3/Caspase-1/Gasdermin D (GSDMD) pathway might be an essential mechanism for loganin treatment of DKD.


Asunto(s)
Diabetes Mellitus , Nefropatías Diabéticas , Ratones , Animales , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Piroptosis , Proteínas NLR , Nefropatías Diabéticas/tratamiento farmacológico , Riñón/metabolismo , Glucosa/farmacología
16.
World J Microbiol Biotechnol ; 39(1): 18, 2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36409383

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) is a zoonotic antibiotic-resistant pathogen that negatively impacts society from medical, veterinary, and societal standpoints. The search for alternative therapeutic strategies and innovative anti-infective agents is urgently needed. Among the pathogenic mechanisms of Staphylococcus aureus (S. aureus), sortase A is a virulence factor of great concern because it is highly linked with the ability of MRSA to invade the host. In this study, we identified that rhodionin, a natural compound of flavonoid glucosides, effectively inhibited the activity of SrtA without affecting the survival and growth of bacteria, and its half maximal inhibitory concentration (IC50) value was 22.85 µg/mL. In vitro, rhodionin prominently attenuated the virulence-related phenotype of SrtA by reducing the adhesion of S. aureus to fibrinogen, reducing the capacity of protein A (SpA) on the bacterial surface and biofilm formation. Subsequently, fluorescence quenching and molecular docking were performed to verify that rhodionin directly bonded to SrtA molecule with KA value of 6.22 × 105 L/mol. More importantly, rhodionin showed a significant protective effect on mice pneumonia model and improved the survival rate of mice. According to the above findings, rhodionin achieved efficacy in the treatment of MRSA-induced infections, which holds promising potential to be developed into a candidate used for MRSA-related infections.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Neumonía Estafilocócica , Ratones , Animales , Staphylococcus aureus , Simulación del Acoplamiento Molecular , Flavonoides/farmacología
17.
Psychooncology ; 31(11): 1941-1950, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36109867

RESUMEN

INTRODUCTION: Major depressive disorder (MDD) is associated with an increased risk of suicide and suicide attempt among cancer patients. However, we do not know how many cancer patients without MDD have suicidal ideation (SI). OBJECTIVES: This study aimed to investigate the prevalence, characteristics and correlated factors of SI among advanced cancer patients without MDD. METHODS: This is a multi-center, cross-sectional study based on an electronic patient-reported outcome systems in patients who were diagnosed with advanced lung, liver, gastric, esophageal, colorectal or breast cancer, the top six prevalent cancers in China. A total of 2930 advanced cancer patients were recruited from 10 regional representative cancer centers across China from August 2019 to December 2020. Patients completed the Patient Health Questionnaire-9 regarding if they had thoughts of being better off dead or of hurting themselves in some way in the previous 2 weeks. Patients also completed the symptom inventory and quality of life assessment. Generalized estimating equation model was performed to explore the correlated factors associated with SI among the patients without MDD. RESULTS: The overall prevalence of SI among advanced cancer patients without MDD was 13.1%. The prevalence was higher in older patients. After adjusted for existing conditions, patients with vomiting symptom (p < 0.001), poorer life quality (p < 0.001), and middle education level (p = 0.031) were correlated factors of SI. CONCLUSIONS: The suicidal ideation is common in advanced cancer patients without MDD. Patients with vomiting, poor quality of life, and middle education level should be screened and monitored for suicidal ideation even without MDD. CLINICAL TRIAL INFORMATION: ChiCTR1900024957.


Asunto(s)
Trastorno Depresivo Mayor , Neoplasias , Humanos , Anciano , Ideación Suicida , Trastorno Depresivo Mayor/epidemiología , Trastorno Depresivo Mayor/diagnóstico , Estudios Transversales , Calidad de Vida , Vómitos , Neoplasias/epidemiología
18.
J Oncol ; 2022: 7531545, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36157227

RESUMEN

Objectives: The integration of patient-reported health status has been increasingly emphasised for delivering high-quality care to advanced cancer patients. This research is designed to track health status changes over time in Chinese advanced cancer patients to explore the risk factors affecting their health status. Methods: Advanced cancer patients were recruited from Peking University Cancer Hospital. An electronic patient-reported outcome (ePRO) system with validated measurements was used to collect the data. ANOVA, the chi-square test, the nonparametric Kruskal-Wallis H test, and generalized estimating equation (GEE) analysis were used for the data analysis. Results: One hundred and three patients completed a baseline survey (T = 0) and two follow-up surveys (T1 = 14 days, T2 = 28 days). Chi-square test results indicate a significant decrease in the percentage of patients reporting moderate or severe difficulty experienced by patients in terms of mobility, pain/discomfort, and anxiety/depression. However, there is a significant increase in the percentage of patients reporting moderate or severe difficulty in self-care and usual activities. Scores on the visual analogue scale in the EQ-5D-5L instrument (EQ-VAS) are associated with patients' income, and the degree of moderate or severe anxiety/depression is found to be associated with employment status. The GEE results show that pain, loss of appetite, poor walking status effected by symptoms, depression, and anxiety has worsened the health status. Conclusions: The health status of Chinese advanced cancer patients under ePRO follow-up in China significantly improves in the physical and psychological dimensions, accompanied by a decrease in usual activities and self-care. Routine screening and rational supportive care are recommended in oncology for cancer care. Based on the rational application of ePRO, longitudinal studies exploring the potential mechanisms of health status changing would provide more beneficial guidance for improving the quality of life in patients with advanced cancer.

19.
Microbiol Spectr ; 10(4): e0095022, 2022 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-35913166

RESUMEN

This study aimed to identify hibifolin as a sortase A (SrtA) inhibitor and to determine whether it could attenuate the virulence of methicillin-resistant Staphylococcus aureus (MRSA). We employed a fluorescence resonance energy transfer (FRET) assay to screen a library of natural molecules to identify compounds that inhibit SrtA activity. Fluorescence quenching assay and molecular docking were performed to verify the direct binding interaction between SrtA and hibifolin. The pneumonia model was established using C57BL/6J mice by MRAS nasal administration for evaluating the effect of hibifolin on the pathogenicity of MRSA. Herein, we found that hibifolin was able to inhibit SrtA activity with an IC50 of 31.20 µg/mL. Further assays showed that the capacity of adhesion of bacteria to the host cells and biofilm formation was decreased in hibifolin-treated USA300. Results obtained from fluorescence quenching assay and molecular docking indicated that hibifolin was capable of targeting SrtA protein directly. This interaction was further confirmed by the finding that the inhibition activities of hibifolin on mutant SrtA were substantially reduced after mutating the binding sites (TRP-194, ALA-104, THR-180, ARG-197, ASN-114). The in vivo study showed that hibifolin in combination with cefotaxime protected mice from USA300 infection-induced pneumonia, which was more potent than cefotaxime alone, and no significant cytotoxicity of hibifolin was observed. Taken together, we identified that hibifolin attenuated the pathogenicity of S. aureus by directly targeting SrtA, which may be utilized in the future as adjuvant therapy for S. aureus infections. IMPORTANCE We identified hibifolin as a sortase A (SrtA) inhibitor by screening the natural compounds library, which effectively inhibited the activity of SrtA with an IC50 value of 31.20 µg/mL. Hibifolin attenuated the pathogenic behavior of Staphylococcus aureus, including adhesion, invasion, and biofilm formation. Binding assays showed that hibifolin bound to SrtA protein directly. Hibifolin improved the survival of pneumonia induced by S. aureus USA300 in mice and alleviated the pathological damage. Moreover, hibifolin showed a synergistic antibacterial effect with cefotaxime in USA300-infected mice.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Neumonía , Infecciones Estafilocócicas , Aminoaciltransferasas , Animales , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Cefotaxima/farmacología , Cisteína Endopeptidasas , Flavonoides , Ratones , Ratones Endogámicos C57BL , Simulación del Acoplamiento Molecular , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus , Virulencia
20.
World J Microbiol Biotechnol ; 38(11): 200, 2022 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-35995893

RESUMEN

Staphylococcus aureus (S. aureus), a Gram-positive bacteria, is an incurable cause of hospital and community-acquired infections. Inhibition bacterial virulence is a viable strategy against S. aureus infections based on the multiple virulence factors secreted by S. aureus. Alpha-hemolysin (Hla) plays a crucial role in bacteria virulence without affecting bacterial viability. Here, we identified that 7,8-Dihydroxyflavone (7,8-DHF), a natural compound, was able to decrease the expression of and did not affect the in vitro growth of S. aureus USA300 at a concentration of 32 µg/mL. It was verified by western blot and RT-qPCR that the natural compound could inhibit the transcription and translation of Hla. Further mechanism studies revealed that 7,8-DHF has a negative effect on transcriptional regulator agrA and RNAIII, preventing the upregulation of virulence gene. Cytotoxicity assays showed that 7,8-DHF did not produce significant cytotoxicity to A549 cells. Animal experiments showed that the combination of 7,8-DHF and vancomycin had a more significant therapeutic effect on S. aureus infection, reflecting the synergistic effect of 7,8-DHF with antibiotics. In conclusion, 7,8-DHF was able to target Hla to protect host cells from hemolysis while limiting the development of bacterial resistance.


Asunto(s)
Toxinas Bacterianas , Flavonas , Infecciones Estafilocócicas , Staphylococcus aureus , Células A549 , Animales , Antibacterianos/metabolismo , Antibacterianos/farmacología , Toxinas Bacterianas/metabolismo , Flavonas/farmacología , Proteínas Hemolisinas/genética , Humanos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/efectos de los fármacos , Virulencia , Factores de Virulencia/genética , Factores de Virulencia/metabolismo
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