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1.
Exp Cell Res ; 442(1): 114228, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39197578

RESUMO

Anterior gradient-2 (AGR2) is highly expressed in several tumors and plays an important role in tumor development. However, the biological function of AGR2 in teratomas has not yet been thoroughly studied. In this study, AGR2 was found to be upregulated in teratoma tissues and in human testicular teratoma cell lines by Western blotting and qRT-PCR assays. A DNA Methylation-Specific PCR assay demonstrated that AGR2 upregulation resulted from hypomethylated AGR2 in teratoma cells. NCC-IT and NT2-D1 cells were transfected with pcDNA-AGR2 or sh-AGR2 to obtain AGR2-overexpressed or -silenced cells, and cell proliferation, invasion and glycolysis were determined using CCK-8, 5-ethynyl-2'-deoxyuridine (EdU), Transwell assays, and commercial kits. The results revealed that overexpression of AGR2 promoted teratoma cell proliferation and invasion and elevated glycolysis levels evidencing by the increase in lactate secretion, glucose consumption, ATP levels and the expression of glycolysis-related proteins, while knockdown of AGR2 showed the opposite results. The interactions between AGR2 and annexin A2 (AnXA2), as well as between AnXA2 and epidermal growth factor receptor (EGFR) were verified by co-immunoprecipitation assay. Mechanistic studies revealed that AGR2 interacts with AnXA2 and increases the level of AnXA2 to recruit more AnXA2 to EGFR, there by promoting EGFR expression. A series of rescue experiments showed that knockdown of AnXA2 or EGFR weakened the promotional effects of AGR2 overexpression on the proliferation, invasion, and glycolysis of teratoma cells. Finally, tumorigenicity assays were performed using NT2-D1 cells stably transfected with either LV-NC-shRNA or LV-shAGR2. The results showed that AGR2 knockdown significantly inhibited teratoma tumor growth in vivo. In conclusion, our data suggested that AGR2 facilitates glycolysis in teratomas through promoting EGFR expression by interacting with AnXA2, thereby promoting teratoma cells proliferation and invasion.


Assuntos
Anexina A2 , Proliferação de Células , Receptores ErbB , Glicólise , Mucoproteínas , Proteínas Oncogênicas , Neoplasias Testiculares , Humanos , Mucoproteínas/genética , Mucoproteínas/metabolismo , Glicólise/genética , Proteínas Oncogênicas/metabolismo , Proteínas Oncogênicas/genética , Animais , Proliferação de Células/genética , Masculino , Receptores ErbB/metabolismo , Receptores ErbB/genética , Camundongos , Anexina A2/metabolismo , Anexina A2/genética , Neoplasias Testiculares/patologia , Neoplasias Testiculares/genética , Neoplasias Testiculares/metabolismo , Linhagem Celular Tumoral , Camundongos Nus , Regulação Neoplásica da Expressão Gênica , Transdução de Sinais , Proteínas/metabolismo , Proteínas/genética , Movimento Celular/genética , Camundongos Endogâmicos BALB C , Invasividade Neoplásica
2.
J Bacteriol ; : e0027224, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39120147

RESUMO

Staphylococcus aureus is commonly isolated from astronauts returning from spaceflight. Previous analysis of omics data from S. aureus low Earth orbit cultures indicated significantly increased expression of the Agr quorum sensing system and its downstream targets in spaceflight samples compared to ground controls. In this current study, the rotary cell culture system (RCCS) was used to investigate the effect of low-shear modeled microgravity (LSMMG) on S. aureus physiology and Agr activity. When cultured in the same growth medium and temperature as the previous spaceflight experiment, S. aureus LSMMG cultures exhibited decreased agr expression and altered growth compared to normal gravity control cultures, which are typically oriented with oxygenation membrane on the bottom of the high aspect rotating vessel (HARV). When S. aureus was grown in an inverted gravity control orientation (oxygenation membrane on top of the HARV), reduced Agr activity was observed relative to both traditional control and LSMMG cultures, signifying that oxygen availability may affect the observed differences in Agr activity. Metabolite assays revealed increased lactate and decreased acetate excretion in both LSMMG and inverted control cultures. Secretomics analysis of LSMMG, control, and inverted control HARV culture supernatants corroborated these results, with inverted and LSMMG cultures exhibiting a decreased abundance of Agr-regulated virulence factors and an increased abundance of proteins expressed in low-oxygen conditions. Collectively, these studies suggest that the orientation of the HARV oxygenation membrane can affect S. aureus physiology and Agr quorum sensing in the RCCS, a variable that should be considered when interpreting data using this ground-based microgravity model.IMPORTANCES. aureus is commonly isolated from astronauts returning from spaceflight and from surfaces within human-inhabited closed environments such as spacecraft. Astronaut health and immune function are significantly altered in spaceflight. Therefore, elucidating the effects of microgravity on S. aureus physiology is critical for assessing its pathogenic potential during long-term human space habitation. These results also highlight the necessity of eliminating potential confounding factors when comparing simulated microgravity model data with actual spaceflight experiments.

3.
Antibiotics (Basel) ; 13(7)2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39061352

RESUMO

There have been few reports regarding the long-term trends in the genotypes of methicillin-resistant Staphylococcus aureus (MRSA) bloodstream isolates. Therefore, this study was performed to investigate the longitudinal trends in the genotypes of MRSA bloodstream isolates obtained from hospitalized patients during a 12-year study period from 2010 to 2021 at a tertiary care university hospital. Over the 12-year period from 2010 to 2021, we conducted a genetic investigation focusing on 245 MRSA strains isolated from the blood of hospitalized patients. The genotypes of the MRSA bloodstream isolates were determined by Staphylococcal Cassette Chromosome mec (SCCmec) typing, accessory gene regulator (agr) typing, PCR-based ORF typing (POT), and multilocus sequence typing (MLST). Strains with the same POT type detected in two or more isolates were designated as epidemic clones, while strains without a common POT type were classified as sporadic clones. Until 2015, isolates with SCCmec II/agr II were prevalent, but isolates with SCCmec IV/agr III increased from 2016. A total of 128 strains (52%) were identified as epidemic clones, while 117 strains (48%) were classified as sporadic clones. The detection rate of sporadic clones increased significantly since 2016 (p < 0.05). The epidemic clones were classified into three clusters, with MRSA of clonal complex (CC) 1 being prominent after 2016. This study showed that the genotypes of MRSA bloodstream isolates underwent a shift from SCCmec II/agr II type to SCCmec IV/agr III type, with a notable increase in MRSA of CC1, after 2016. There was a significant increase in the proportion of sporadic strains among the isolates, suggesting the diversification of genotypes.

4.
Biomolecules ; 14(7)2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-39062458

RESUMO

The anterior gradient protein 2 (AGR2) plays a crucial role in facilitating the formation of protein disulfide bonds within the endoplasmic reticulum (ER). Research suggests that AGR2 can function as an oncogene, with its heightened expression linked to the advancement of hepatobiliary and pancreatic cancers through invasion and metastasis. Notably, AGR2 not only serves as a pro-oncogenic agent but also as a downstream targeting protein, indirectly fostering cancer progression. This comprehensive review delves into the established functions and expression patterns of AGR2, emphasizing its pivotal role in cancer progression, particularly in hepatobiliary and pancreatic malignancies. Furthermore, AGR2 emerges as a potential cancer prognostic marker and a promising target for immunotherapy, offering novel avenues for the treatment of hepatobiliary and pancreatic cancers and enhancing patient outcomes.


Assuntos
Mucoproteínas , Proteínas Oncogênicas , Neoplasias Pancreáticas , Humanos , Mucoproteínas/metabolismo , Mucoproteínas/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Proteínas Oncogênicas/metabolismo , Proteínas Oncogênicas/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Animais , Neoplasias do Sistema Biliar/genética , Neoplasias do Sistema Biliar/metabolismo , Neoplasias do Sistema Biliar/tratamento farmacológico , Neoplasias do Sistema Biliar/terapia , Neoplasias do Sistema Biliar/patologia , Regulação Neoplásica da Expressão Gênica , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genética
5.
mBio ; 15(8): e0166724, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39037272

RESUMO

Severe COVID-19 has been associated with coinfections with bacterial and fungal pathogens. Notably, patients with COVID-19 who develop Staphylococcus aureus bacteremia exhibit higher rates of mortality than those infected with either pathogen alone. To understand this clinical scenario, we collected and examined S. aureus blood and respiratory isolates from a hospital in New York City during the early phase of the pandemic from both SARS-CoV-2+ and SARS-CoV-2- patients. Whole genome sequencing of these S. aureus isolates revealed broad phylogenetic diversity in both patient groups, suggesting that SARS-CoV-2 coinfection was not associated with a particular S. aureus lineage. Phenotypic characterization of the contemporary collection of S. aureus isolates from SARS-CoV-2+ and SARS-CoV-2- patients revealed no notable differences in several virulence traits examined. However, we noted a trend toward overrepresentation of S. aureus bloodstream strains with low cytotoxicity in the SARS-CoV-2+ group. We observed that patients coinfected with SARS-CoV-2 and S. aureus were more likely to die during the acute phase of infection when the coinfecting S. aureus strain exhibited high or low cytotoxicity. To further investigate the relationship between SARS-CoV-2 and S. aureus infections, we developed a murine coinfection model. These studies revealed that infection with SARS-CoV-2 renders mice susceptible to subsequent superinfection with low cytotoxicity S. aureus. Thus, SARS-CoV-2 infection sensitizes the host to coinfections, including S. aureus isolates with low intrinsic virulence. IMPORTANCE: The COVID-19 pandemic has had an enormous impact on healthcare across the globe. Patients who were severely infected with SARS-CoV-2, the virus causing COVID-19, sometimes became infected with other pathogens, which is termed coinfection. If the coinfecting pathogen is the bacterium Staphylococcus aureus, there is an increased risk of patient death. We collected S. aureus strains that coinfected patients with SARS-CoV-2 to study the disease outcome caused by the interaction of these two important pathogens. We found that both in patients and in mice, coinfection with an S. aureus strain lacking toxicity resulted in more severe disease during the early phase of infection, compared with infection with either pathogen alone. Thus, SARS-CoV-2 infection can directly increase the severity of S. aureus infection.


Assuntos
COVID-19 , Coinfecção , SARS-CoV-2 , Infecções Estafilocócicas , Staphylococcus aureus , COVID-19/complicações , COVID-19/microbiologia , Coinfecção/microbiologia , Coinfecção/virologia , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidade , Infecções Estafilocócicas/microbiologia , Humanos , Animais , Camundongos , SARS-CoV-2/genética , Filogenia , Feminino , Cidade de Nova Iorque/epidemiologia , Masculino , Virulência , Pessoa de Meia-Idade , Sequenciamento Completo do Genoma , Bacteriemia/microbiologia , Modelos Animais de Doenças , Idoso
6.
Heliyon ; 10(12): e32389, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38975180

RESUMO

Despite being an innocuous commensal of human skin and mucous membranes, Staphylococcus epidermidis, infects surgical wounds and causes infections through biofilm formation. This study evaluates, in a time-dependent experiment, the self-dispersion of S. epidermidis CIP 444 biofilm when formed on borosilicate glass (hydrophilic) and polystyrene (hydrophobic) surfaces, using physical and molecular approaches. During a seven-day period of incubation, absorbance measurement revealed a drop in biofilm optical density on both studied surfaces on day 4 (0.043-0.035 nm/cm2, polystyrene), (0.06-0.053 nm/cm2, borosilicate glass). Absorbance results were correlated with crystal violet staining that showed a clear detachment from day 4. The blue color increases again on day 7, with an increase in biofilm optical density indicating the regeneration of the biofilm. Changes in gene expression in the S. epidermidis biofilm were assessed using a real-time reverse transcription-polymerase chain reaction. High expression of agr genes was detected on days 4 and 5, confirming our supposition of dispersion in this period, autolysin genes like atlE1 and aae were upregulated from day 3 until day 6 and the genes responsible for slime production and biofilm accumulation, were upregulated on days 4, 5, and 6 (ica ADBC) and on days 5, 6 and 7 (aap), indicating a dual process taking place. These findings suggest that S. epidermidis CIP 444 biofilms disperse at day 4 and reform at day 7. Over the course of the seven-day investigation, 2-ΔΔCt results showed that some genes in the biofilm were dramatically enhanced while others were significantly decreased as compared to planktonic ones.

7.
J Extracell Biol ; 3(2): e141, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38939899

RESUMO

Epithelial-mesenchymal transition (EMT) is associated with tumorigenesis and drug resistance. The Rab superfamily of small G-proteins plays a role in regulating cell cytoskeleton and vesicle transport. However, it is not yet clear how the Rab family contributes to cancer progression by participating in EMT. By analysing various in silico datasets, we identified a statistically significant increase in RAB31 expression in the oxaliplatin-resistant group compared to that in the parental or other chemotherapy drug groups. Our findings highlight RAB31's powerful effect on colorectal cancer cell lines when compared with other family members. In a study that analysed multiple online meta-databases, RAB31 RNA levels were continually detected in colorectal tissue arrays. Additionally, RAB31 protein levels were correlated with various clinical parameters in clinical databases and were associated with negative prognoses for patients. RAB31 expression levels in all three probes were calculated using a computer algorithm and were found to be positively correlated with EMT scores. The expression of the epithelial-type marker CDH1 was suppressed in RAB31 overexpression models, whereas the expression of the mesenchymal-type markers SNAI1 and SNAI2 increased. Notably, RAB31-induced EMT and drug resistance are dependent on extracellular vesicle (EV) secretion. Interactome analysis confirmed that RAB31/AGR2 axis-mediated exocytosis was responsible for maintaining colorectal cell resistance to oxaliplatin. Our study concluded that RAB31 alters the sensitivity of oxaliplatin, a supplementary chemotherapy approach, and is an independent prognostic factor that can be used in the treatment of colorectal cancer.

8.
Indian J Endocrinol Metab ; 28(2): 208-212, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38911105

RESUMO

Introduction: Assessment of genitalia is an important part of the neonatal examination. Regional, racial, and ethnic variations in phallic length have been documented. Clitoral dimensions may also show similar variations. Normal values for neonatal clitoral measurements may help the pediatrician/neonatologist to accurately diagnose clitoromegaly and underlying etiology to guide appropriate investigations. Data on clitoral measurements is limited with only one study from India (Kolkata). Hence we aimed in this study to generate south Indian data on neonatal clitoral dimensions, anogenital distance, and anogenital ratio. Two hundred and fifty two hemodynamically stable term female neonates without ambiguous genitalia/vulval masses born in a community hospital. Hospital-based cross-sectional study. 1. To measure clitoral dimensions, anogenital distance, and anogenital ratio in female neonates. 2. To correlate clitoral dimensions, anogenital distance, and ratio with anthropometric measurements, gestational age, and maternal comorbidities. Methods: Measurements were recorded using a digital vernier caliper, under strict aseptic precautions with labia majora gently separated and the baby held in a frog-leg position. Clitoral length, width, and anogenital distance were measured and anogenital ratio and clitoral index were calculated. Results: In term neonates, the mean ± SD of clitoral length (CL), clitoral width (CW), anogenital ratio (AGR) were 6.34 ± 1.75 mm, 6.39 ± 1.27 mm and 0.39 ± 0.05, respectively. The 3rd and 97th centiles for mean clitoral length were 3.55 and 9.93 mm, for mean clitoral width were 3.37 and 8.35 mm, and for AGR were 0.28 and 0.48, respectively. These clitoral dimensions in south Indian neonates were higher than those from East India (Kolkata), lower than Nigerian babies, and similar to Israeli neonates. Mean CL and CW had no statistical correlation with birth weight, gestational age, head circumference, or length in term neonates. A significant correlation was noted between pregnancy-induced hypertension and mean clitoral width, and between gestational diabetes and AGR. Conclusion: Normative values for clitoral dimensions (length and width) and AGR for south Indian term female neonates have been established. 97th centiles of 9.93 mm (CL) and 8.35 mm (CW) and 0.48 mm (AGR) may be used as practical cut-offs to diagnose clitoromegaly and virilization. Clitoral measurements had no statistical correlation with birth weight, gestational age, or anthropometry. Clitoral measurements exhibit ethnic and racial differences, thus emphasizing the importance of regional cut-offs and need for more studies from different parts of India on CL.

9.
Cell Mol Biol Lett ; 29(1): 84, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822246

RESUMO

BACKGROUND: Canine mammary tumors (CMTs) in intact female dogs provide a natural model for investigating metastatic human cancers. Our prior research identified elevated expression of Anterior Gradient 2 (AGR2), a protein disulfide isomerase (PDI) primarily found in the endoplasmic reticulum (ER), in CMT tissues, highly associated with CMT progression. We further demonstrated that increased AGR2 expression actively influences the extracellular microenvironment, promoting chemotaxis in CMT cells. Unraveling the underlying mechanisms is crucial for assessing the potential of therapeutically targeting AGR2 as a strategy to inhibit a pro-metastatic microenvironment and impede tumor metastasis. METHODS: To identify the AGR2-modulated secretome, we employed proteomics analysis of the conditioned media (CM) from two CMT cell lines ectopically expressing AGR2, compared with corresponding vector-expressing controls. AGR2-regulated release of 14-3-3ε (gene: YWHAE) and α-actinin 4 (gene: ACTN4) was validated through ectopic expression, knockdown, and knockout of the AGR2 gene in CMT cells. Extracellular vesicles derived from CMT cells were isolated using either differential ultracentrifugation or size exclusion chromatography. The roles of 14-3-3ε and α-actinin 4 in the chemotaxis driven by the AGR2-modulated CM were investigated through gene knockdown, antibody-mediated interference, and recombinant protein supplement. Furthermore, the clinical relevance of the release of 14-3-3ε and α-actinin 4 was assessed using CMT tissue-immersed saline and sera from CMT-afflicted dogs. RESULTS: Proteomics analysis of the AGR2-modulated secretome revealed increased abundance in 14-3-3ε and α-actinin 4. Ectopic expression of AGR2 significantly increased the release of 14-3-3ε and α-actinin 4 in the CM. Conversely, knockdown or knockout of AGR2 expression remarkably reduced their release. Silencing 14-3-3ε or α-actinin 4 expression diminished the chemotaxis driven by AGR2-modulated CM. Furthermore, AGR2 controls the release of 14-3-3ε and α-actinin 4 primarily via non-vesicular routes, responding to the endoplasmic reticulum (ER) stress and autophagy activation. Knockout of AGR2 resulted in increased α-actinin 4 accumulation and impaired 14-3-3ε translocation in autophagosomes. Depletion of extracellular 14-3-3ε or α-actinin 4 reduced the chemotaxis driven by AGR2-modulated CM, whereas supplement with recombinant 14-3-3ε in the CM enhanced the CM-driven chemotaxis. Notably, elevated levels of 14-3-3ε or α-actinin 4 were observed in CMT tissue-immersed saline compared with paired non-tumor samples and in the sera of CMT dogs compared with healthy dogs. CONCLUSION: This study elucidates AGR2's pivotal role in orchestrating unconventional secretion of 14-3-3ε and α-actinin 4 from CMT cells, thereby contributing to paracrine-mediated chemotaxis. The insight into the intricate interplay between AGR2-involved ER stress, autophagy, and unconventional secretion provides a foundation for refining strategies aimed at impeding metastasis in both canine mammary tumors and potentially human cancers.


Assuntos
Proteínas 14-3-3 , Actinina , Autofagia , Quimiotaxia , Estresse do Retículo Endoplasmático , Neoplasias Mamárias Animais , Mucoproteínas , Animais , Cães , Proteínas 14-3-3/metabolismo , Proteínas 14-3-3/genética , Feminino , Actinina/metabolismo , Actinina/genética , Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/genética , Neoplasias Mamárias Animais/patologia , Linhagem Celular Tumoral , Quimiotaxia/genética , Autofagia/genética , Estresse do Retículo Endoplasmático/genética , Mucoproteínas/genética , Mucoproteínas/metabolismo , Proteínas Oncogênicas/metabolismo , Proteínas Oncogênicas/genética
10.
Phytomedicine ; 130: 155590, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38810547

RESUMO

BACKGROUND: Staphylococcus aureus is a versatile pathogen that can cause a wide range of infections in humans. Biofilms play a crucial role in the pathogenicity of S. aureus and contribute to its ability to cause persistent and chronic infections. Baohuoside I has garnered increasing recognition as a natural flavonol glycoside with a wide spectrum of health-related activities. PURPOSE: The antibacterial and anti-biofilm properties of Baohuoside I have not been extensively investigated. Our study aimed to assess its inhibitory effects and the underlying mechanisms on biofilm formation and hemolytic capacity in S. aureus. STUDY DESIGN/METHODS: The impact of Baohuoside I on the biofilm and virulence of S. aureus was evaluated through in vitro experiments and Galleria mellonella as an in vivo infection model. The mechanisms were explored by Drug affinity responsive target stability (DARTS) and validated in genetic knockout strain and through molecular biological experiments using DARTS, molecular docking, electrophoretic mobility shift assay (EMSA), and bio-layer interferometry (BLI). RESULTS: Baohuoside I significantly inhibits the formation of S. aureus biofilms and hemolytic activity at 6.25 µM. Proteomics analysis revealed that treatment with Baohuoside I led to a reduction in the expression of quorum-sensing system agr-regulated genes. DARTS analysis identified Staphylococcus accessory regulator factor (SarZ), a key regulator involved in the expression of virulence factors in S. aureus by acting as activator of the agr quorum-sensing system, was the direct target of Baohuoside I. Molecular docking, DARTS, BLI and EMSA assays collectively confirmed the direct binding of Baohuoside I to SarZ, inhibiting its binding to downstream promoters. Furthermore, it is found through site-directed protein mutagenesis that the Tyr27 and Phe117 residues are key for Baohuoside I binding to SarZ. Additionally, the knockout of SarZ significantly diminished the hemolytic ability of S. aureus, underscoring its crucial role as a pivotal regulator of virulence. Lastly, in vivo tests utilizing the G. mellonella infection model demonstrated the efficacy of Baohuoside I. CONCLUSION: This study provides valuable insights into the mechanism by which Baohuoside I inhibits the virulence of S. aureus through its interaction with SarZ. These findings highlight the significance of SarZ as an effective target against the virulence of S. aureus.


Assuntos
Antibacterianos , Proteínas de Bactérias , Biofilmes , Simulação de Acoplamento Molecular , Biofilmes/efeitos dos fármacos , Animais , Virulência/efeitos dos fármacos , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Mariposas/microbiologia , Mariposas/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Hemólise/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade , Testes de Sensibilidade Microbiana
11.
Front Cell Infect Microbiol ; 14: 1367016, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38681224

RESUMO

Introduction: Staphylococcus aureus, is a pathogen commonly encountered in both community and hospital settings. Patients receiving hemodialysis treatment face an elevated risk of vascular access infections (VAIs) particularly Staphylococcus aureus, infection. This heightened risk is attributed to the characteristics of Staphylococcus aureus, , enabling it to adhere to suitable surfaces and form biofilms, thereby rendering it resistant to external interventions and complicating treatment efforts. Methods: Therefore this study utilized PCR and microtiter dish biofilm formation assay to determine the difference in the virulence genes and biofilm formation among in our study collected of 103 Staphylococcus aureus, isolates from hemodialysis patients utilizing arteriovenous grafts (AVGs), tunneled cuffed catheters (TCCs), and arteriovenous fistulas (AVFs) during November 2013 to December 2021. Results: Our findings revealed that both MRSA and MSSA isolates exhibited strong biofilm production capabilities. Additionally, we confirmed the presence of agr types and virulence genes through PCR analysis. The majority of the collected isolates were identified as agr type I. However, agr type II isolates displayed a higher average number of virulence genes, with MRSA isolates exhibiting a variety of virulence genes. Notably, combinations of biofilm-associated genes, such as eno-clfA-clfB-fib-icaA-icaD and eno-clfA-clfB-fib-fnbB-icaA-icaD, were prevalent among Staphylococcus aureus, isolates obtained from vascular access infections. Discussion: These insights contribute to a better understanding of the molecular characteristics associated with Staphylococcus aureus, infections in hemodialysis patients and provided more targeted and effective treatment approaches.


Assuntos
Proteínas de Bactérias , Biofilmes , Diálise Renal , Infecções Estafilocócicas , Staphylococcus aureus , Transativadores , Fatores de Virulência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Infecções Relacionadas a Cateter/microbiologia , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Diálise Renal/efeitos adversos , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidade , Transativadores/genética , Fatores de Virulência/genética
12.
Front Pharmacol ; 15: 1365815, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38659576

RESUMO

The virulence of Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA), depends on the expression of toxins and virulence factors controlled by the quorum-sensing (QS) system, encoded on the virulence accessory gene regulator (agr) locus. The aim of this study was to identify a phytochemical that inhibits Agr-QS function and to elucidate its mechanism. We screened 577 compounds and identified physalin H, physalin B, and isophysalin B--phytochemicals belonging to physalins found in plants of the Solanaceae family--as novel Agr-QS modulators. Biological analyses and in vitro protein-DNA binding assays suggested that these physalins suppress gene expression related to the Agr-QS system by inhibiting binding of the key response regulator AgrA to the agr promoters, reducing the function of hemolytic toxins downstream of these genes in MRSA. Furthermore, although physalin F suppressed gene expression in the Agr-QS system, its anti-hemolytic activity was lower than that of physalins H, B, and isophysalin B. Conversely, five physalins isolated from the same plant with the ability to suppress Agr-QS did not reduce bacterial Agr-QS activity but inhibited AgrA binding to DNA in vitro. A docking simulation revealed that physalin interacts with the DNA-binding site of AgrA in three docking states. The carbonyl oxygens at C-1 and C-18 of physalins, which can suppress Agr-QS, were directed to residues N201 and R198 of AgrA, respectively, whereas these carbonyl oxygens of physalins, without Agr-QS suppression activity, were oriented in different directions. Next, 100-ns molecular dynamics simulations revealed that the hydrogen bond formed between the carbonyl oxygen at C-15 of physalins and L186 of AgrA functions as an anchor, sustaining the interaction between the carbonyl oxygen at C-1 of physalins and N201 of AgrA. Thus, these results suggest that physalin H, physalin B, and isophysalin B inhibit the interaction of AgrA with the agr promoters by binding to the DNA-binding site of AgrA, suppressing the Agr-QS function of S. aureus. Physalins that suppress the Agr-QS function are proposed as potential lead compounds in the anti-virulence strategy for MRSA infections.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38571296

RESUMO

BACKGROUND: There is insufficient data to support a link between serum AGR and mortality in individuals with diabetes. This prospective study sought to investigate the relationship between serum AGR and all-cause and cause-specific mortality in adult diabetics. METHODS: This study included 8508 adults with diabetes from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018. Death outcomes were ascertained by linkage to National Death Index records through 31 December 2019. Hazard ratios (HR) and 95% confidence intervals (CIs) for mortality from all causes, cardiovascular disease (CVD), and cancer were estimated using weighted Cox proportional hazards models. RESULTS: 2415 all-cause deaths, including 688 cardiovascular deaths and 413 cancer deaths, were recorded over an average of 9.61 years of follow-up. After multivariate adjustment, there was a significant and linear relationship between higher serum AGR levels and reduced all-cause and cause-specific mortality in a dose-response manner. The multivariate-adjusted HR and 95% CI for all-cause mortality (Ptrend<0.0001), cardiovascular mortality (Ptrend<0.001), and cancer mortality (Ptrend<0.01) were 0.51(0.42,0.60), 0.62(0.46,0.83), and 0.57(0.39,0.85), respectively, for individuals in the highest AGR quartile. There was a 73% decreased risk of all-cause death per one-unit rise in natural log-transformed serum AGR, as well as a 60% and 63% decreased risk of mortality from CVD and cancer, respectively (all P<0.001). Both the stratified analysis and the sensitivity analyses revealed the same relationships. CONCLUSIONS: AGR is a promising biomarker in risk predictions for long-term mortality in diabetic individuals, particularly in those under age 60 and heavy drinker.

14.
Heliyon ; 10(7): e28175, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38560175

RESUMO

Background: Anterior gradient 2 (AGR2) is highly enriched in several malignant tumors and can boost tumor metastasis. Whereas, AGR2 role in colorectal cancer (CRC) is not clear. Methods: AGR2 expression in the GEPIA database was studied, and the results were confirmed by Western blot in CRC cell lines (SW480, SW620, and HT-29). The impact of AGR2 on the multiplication, migration, invasion and EMT of CRC cells were studied by CCK-8 assay, as well as clone formation, wound healing and transwell assays. The protein concent related to the AKT/ß-catenin signaling pathway were accessed via Western blot. Results: AGR2 concent in CRC tissues was notablely boosted versus normal colorectal tissues. Exogenous AGR2 boosted the multiplication of CRC cells. In addition, exogenous AGR2 induced EMT, which demonstrated that ZEB1, N-cadherin, Vimentin, Slug, Snail protein concent boosted and E-cadherin protein abated in CRC cells. In terms of mechanism, exogenous AGR2 upgulated p-AKT/AKT, p-GSK3ß/GSK3ß and ß-catenin concent. Exogenous AGR2 combined with AKT agonist IGF- Ⅰ can further enhance the multiplication, migration and invasion of CRC cells. Conclusion: Exogenous AGR2 enhances the multiplication of CRC cells and induces EMT process, the mechanism of which is related to AKT/ß-catenin signal pathway.

15.
Front Oncol ; 14: 1321694, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38595814

RESUMO

Multiple cancer cell types are found in prostate tumors. They are either luminal-like adenocarcinoma or less luminal-like and more stem-like non-adenocarcinoma and small cell carcinoma. These types are lineage related through differentiation. Loss of cancer differentiation from luminal-like to stem-like is mediated by the activation of stem cell transcription factors (scTF) such as LIN28A, NANOG, POU5F1 and SOX2. scTF expression leads to down-regulation of ß2-microglobulin (B2M). Thus, cancer cells can change from the scTF˜B2Mhi phenotype of differentiated to that of scTF˙B2Mlo of dedifferentiated in the disease course. In development, epithelial cell differentiation is induced by stromal signaling and cell contact. One of the stromal factors specific to prostate encodes proenkephalin (PENK). PENK can down-regulate scTF and up-regulate B2M in stem-like small cell carcinoma LuCaP 145.1 cells indicative of exit from the stem state and differentiation. In fact, prostate cancer cells can be made to undergo dedifferentiation or reprogramming by scTF transfection and then to differentiate by PENK transfection. Therapies need to be designed for treating the different cancer cell types. Extracellular anterior gradient 2 (eAGR2) is an adenocarcinoma antigen associated with cancer differentiation that can be targeted by antibodies to lyse tumor cells with immune system components. eAGR2 is specific to cancer as normal cells express only the intracellular form (iAGR2). For AGR2-negative stem-like cancer cells, factors like PENK that can target scTF could be effective in differentiation therapy.

16.
Elife ; 122024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38687677

RESUMO

The agr quorum-sensing system links Staphylococcus aureus metabolism to virulence, in part by increasing bacterial survival during exposure to lethal concentrations of H2O2, a crucial host defense against S. aureus. We now report that protection by agr surprisingly extends beyond post-exponential growth to the exit from stationary phase when the agr system is no longer turned on. Thus, agr can be considered a constitutive protective factor. Deletion of agr resulted in decreased ATP levels and growth, despite increased rates of respiration or fermentation at appropriate oxygen tensions, suggesting that Δagr cells undergo a shift towards a hyperactive metabolic state in response to diminished metabolic efficiency. As expected from increased respiratory gene expression, reactive oxygen species (ROS) accumulated more in the agr mutant than in wild-type cells, thereby explaining elevated susceptibility of Δagr strains to lethal H2O2 doses. Increased survival of wild-type agr cells during H2O2 exposure required sodA, which detoxifies superoxide. Additionally, pretreatment of S. aureus with respiration-reducing menadione protected Δagr cells from killing by H2O2. Thus, genetic deletion and pharmacologic experiments indicate that agr helps control endogenous ROS, thereby providing resilience against exogenous ROS. The long-lived 'memory' of agr-mediated protection, which is uncoupled from agr activation kinetics, increased hematogenous dissemination to certain tissues during sepsis in ROS-producing, wild-type mice but not ROS-deficient (Cybb-/-) mice. These results demonstrate the importance of protection that anticipates impending ROS-mediated immune attack. The ubiquity of quorum sensing suggests that it protects many bacterial species from oxidative damage.


Assuntos
Proteínas de Bactérias , Regulação Bacteriana da Expressão Gênica , Peróxido de Hidrogênio , Estresse Oxidativo , Percepção de Quorum , Staphylococcus aureus , Transativadores , Staphylococcus aureus/genética , Staphylococcus aureus/fisiologia , Staphylococcus aureus/metabolismo , Percepção de Quorum/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Animais , Transativadores/metabolismo , Transativadores/genética , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , Camundongos , Infecções Estafilocócicas/microbiologia , Viabilidade Microbiana , Espécies Reativas de Oxigênio/metabolismo , Deleção de Genes
17.
Antibiotics (Basel) ; 13(2)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38391516

RESUMO

Staphylococcus pseudintermedius is a frequent cause of infections in dogs. Infectious isolates of this coagulase-positive staphylococcal species are often methicillin- and multidrug-resistant, which complicates therapy. In staphylococci, methicillin resistance is encoded by determinants found on mobile genetic elements called Staphylococcal Chromosome Cassette mec (SCCmec), which, in addition to methicillin resistance factors, sometimes encode additional genes, such as further resistance factors and, rarely, virulence determinants. In this study, we analyzed SCCmec in a collection of infectious methicillin-resistant S. pseudintermedius (MRSP) isolates from predominant lineages in the United States. We found that several lineages characteristically have specific types of SCCmec elements and Agr types and harbor additional factors in their SCCmec elements that may promote virulence or affect DNA uptake. All isolates had SCCmec-encoded restriction-modification (R-M) systems of types I or II, and sequence types (STs) ST84 and ST64 had one type II and one type I R-M system, although the latter lacked a complete methylation enzyme gene. ST68 isolates also had an SCCmec-encoded CRISPR system. ST71 isolates had a psm-mec gene, which, in all but apparently Agr-dysfunctional isolates, produced a PSM-mec peptide toxin, albeit at relatively small amounts. This study gives detailed insight into the composition of SCCmec elements in infectious isolates of S. pseudintermedius and lays the genetic foundation for further efforts directed at elucidating the contribution of identified accessory SCCmec factors in impacting SCCmec-encoded and thus methicillin resistance-associated virulence and resistance to DNA uptake in this leading canine pathogen.

18.
Nutrients ; 16(3)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38337727

RESUMO

Panax ginseng, a traditional Chinese medicine with a history spanning thousands of years, faces overexploitation and challenges related to extended growth periods. Tissue-cultured adventitious roots and stem cells are alternatives to wild and field-cultivated ginseng. In this study, we assessed the in vitro xanthine oxidase and α-glucosidase inhibitory activities of saponin extracts among cultured cambial meristematic cells (CMC), adventitious ginseng roots (AGR), and field-cultivated ginseng roots (CGR). The xanthine oxidase (XO) and α-glucosidase inhibitory activities were determined by uric acid estimation and the p-NPG method, respectively. Spectrophotometry and the Folin-Ciocalteu, aluminum nitrate, and Bradford methods were employed to ascertain the total saponins and phenolic, flavonoid, and protein contents. The calculated IC50 values for total saponin extracts against XO and α-glucosidase were 0.665, 0.844, and >1.6 mg/mL and 0.332, 0.745, and 0.042 mg/mL for AGR, CMC, CGR, respectively. Comparing the total saponin, crude protein, and total phenolic contents revealed that AGR > CMC > CGR. To the best of our knowledge, this study presents the first report on the in vitro comparison of xanthine oxidase and α-glucosidase inhibitory activities among AGR, CMC, and CGR. The findings offer valuable insights into the development of hypoglycemic and antihyperuricemic medicinal, nutraceutical, and functional products utilizing AGR and CMC.


Assuntos
Panax , Saponinas , Panax/metabolismo , Xantina Oxidase/metabolismo , alfa-Glucosidases/metabolismo , Raízes de Plantas/metabolismo
19.
In Vivo ; 38(2): 904-910, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38418138

RESUMO

BACKGROUND/AIM: The albumin-globulin ratio (AGR) is a useful biomarker for predicting postoperative complications and a poor prognosis in patients with various types of cancer and can be evaluated without invasive testing or surgery. In this study, we aimed to evaluate the usefulness of the AGR in predicting the short- and long-term prognoses of patients with gastric cancer who underwent radical resection at our institution. PATIENTS AND METHODS: This study is a retrospective cohort analysis in which eligible patients were selected from the medical records of patients who underwent radical resection for gastric cancer at Yokohama City University from 2000 to 2020 and their medical records were reviewed. A total of 240 patients with gastric cancer were classified into high-AGR (>1.57) and low-AGR (≤1.57) groups and their overall survival (OS), recurrence-free survival (RFS), and postoperative complication rates were compared. RESULTS: Of the total 240 patients, 87 were classified into the high AGR group and 153 were classified into the low AGR group; the incidence of postoperative complications in the two groups did not differ to a statistically significant extent (34.4% vs. 39.2%, p=0.491). The long-term findings showed that the 5-year OS and RFS rates were significantly better in the high AGR group [84.0% vs. 64.8% (p=0.005), 80.0% vs. 61.9% (p=0.015), respectively]. CONCLUSION: Preoperative low AGR is a risk factor for OS and DFS in patients with gastric cancer who undergo surgery. The AGR may be a useful biomarker that can be applied as a prognostic indicator for patients with gastric cancer.


Assuntos
Globulinas , Neoplasias Gástricas , Humanos , Prognóstico , Albumina Sérica/análise , Estudos Retrospectivos , Neoplasias Gástricas/cirurgia , Biomarcadores , Complicações Pós-Operatórias
20.
Cureus ; 16(1): e51671, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38313993

RESUMO

Background Measurement of serum/plasma levels of inflammatory factors in restless legs syndrome (RLS) has been the subject of a few studies, as various inflammatory diseases may demonstrate an association with RLS. The albumin/globulin ratio (AGR) is a parameter that considers two proteins that are indicators of inflammation and has been shown to increase in some inflammatory diseases. No study has evaluated the relationship between RLS and AGR yet. In our study, we examined the usability of AGR as a diagnostic biomarker in RLS patients. Methodology A total of 88 patients and 89 control individuals were included in the study retrospectively. The two groups were compared in terms of AGR levels. RLS patients were divided into four groups according to the International Restless Legs Syndrome Study Group Rating Scale score and the relationship between disease severity and AGR values ​​was examined. Results Albumin levels of the study group were higher than the control group. There was no statistically significant difference between the groups regarding globulin and AGR levels. Conclusions Serum albumin levels could be useful in RLS compared to globulin or AGR values. This needs to be supported by new studies with larger patient series, multicenter design, and including multiple parameters such as patients' muscle mass, nutritional habits, and exercise status.

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