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1.
Nat Immunol ; 22(2): 193-204, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33398181

RESUMO

Metabolic reprograming toward aerobic glycolysis is a pivotal mechanism shaping immune responses. Here we show that deficiency in NF-κB-inducing kinase (NIK) impairs glycolysis induction, rendering CD8+ effector T cells hypofunctional in the tumor microenvironment. Conversely, ectopic expression of NIK promotes CD8+ T cell metabolism and effector function, thereby profoundly enhancing antitumor immunity and improving the efficacy of T cell adoptive therapy. NIK regulates T cell metabolism via a NF-κB-independent mechanism that involves stabilization of hexokinase 2 (HK2), a rate-limiting enzyme of the glycolytic pathway. NIK prevents autophagic degradation of HK2 through controlling cellular reactive oxygen species levels, which in turn involves modulation of glucose-6-phosphate dehydrogenase (G6PD), an enzyme that mediates production of the antioxidant NADPH. We show that the G6PD-NADPH redox system is important for HK2 stability and metabolism in activated T cells. These findings establish NIK as a pivotal regulator of T cell metabolism and highlight a post-translational mechanism of metabolic regulation.


Assuntos
Linfócitos T CD8-Positivos/enzimologia , Neoplasias do Colo/enzimologia , Metabolismo Energético , Ativação Linfocitária , Linfócitos do Interstício Tumoral/enzimologia , Melanoma Experimental/enzimologia , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/transplante , Linhagem Celular Tumoral , Neoplasias do Colo/imunologia , Neoplasias do Colo/patologia , Neoplasias do Colo/terapia , Citotoxicidade Imunológica , Estabilidade Enzimática , Feminino , Glucosefosfato Desidrogenase/metabolismo , Glicólise , Hexoquinase/genética , Hexoquinase/metabolismo , Imunoterapia Adotiva , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/transplante , Masculino , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Melanoma Experimental/terapia , Camundongos Endogâmicos C57BL , Camundongos Knockout , NADP/metabolismo , Fenótipo , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Microambiente Tumoral , Quinase Induzida por NF-kappaB
3.
Mol Cell ; 80(3): 410-422.e6, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33108758

RESUMO

While effective anti-cancer drugs targeting the CHK1 kinase are advancing in the clinic, drug resistance is rapidly emerging. Here, we demonstrate that CRISPR-mediated knockout of the little-known gene FAM122A/PABIR1 confers cellular resistance to CHK1 inhibitors (CHK1is) and cross-resistance to ATR inhibitors. Knockout of FAM122A results in activation of PP2A-B55α, a phosphatase that dephosphorylates the WEE1 protein and rescues WEE1 from ubiquitin-mediated degradation. The resulting increase in WEE1 protein expression reduces replication stress, activates the G2/M checkpoint, and confers cellular resistance to CHK1is. Interestingly, in tumor cells with oncogene-driven replication stress, CHK1 can directly phosphorylate FAM122A, leading to activation of the PP2A-B55α phosphatase and increased WEE1 expression. A combination of a CHK1i plus a WEE1 inhibitor can overcome CHK1i resistance of these tumor cells, thereby enhancing anti-cancer activity. The FAM122A expression level in a tumor cell can serve as a useful biomarker for predicting CHK1i sensitivity or resistance.


Assuntos
Quinase 1 do Ponto de Checagem/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fosfoproteínas/metabolismo , Pirazinas/farmacologia , Pirazóis/farmacologia , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quinase 1 do Ponto de Checagem/antagonistas & inibidores , Quinase 1 do Ponto de Checagem/metabolismo , Dano ao DNA/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Proteínas Nucleares/metabolismo , Fosfoproteínas/fisiologia , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Tirosina Quinases/genética , Pirazinas/metabolismo , Pirazóis/metabolismo , Transdução de Sinais/efeitos dos fármacos
4.
Nature ; 575(7783): 523-527, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31723267

RESUMO

The protection of telomere ends by the shelterin complex prevents DNA damage signalling and promiscuous repair at chromosome ends. Evidence suggests that the 3' single-stranded telomere end can assemble into a lasso-like t-loop configuration1,2, which has been proposed to safeguard chromosome ends from being recognized as DNA double-strand breaks2. Mechanisms must also exist to transiently disassemble t-loops to allow accurate telomere replication and to permit telomerase access to the 3' end to solve the end-replication problem. However, the regulation and physiological importance of t-loops in the protection of telomere ends remains unknown. Here we identify a CDK phosphorylation site in the shelterin subunit at Ser365 of TRF2, whose dephosphorylation in S phase by the PP6R3 phosphatase provides a narrow window during which the RTEL1 helicase can transiently access and unwind t-loops to facilitate telomere replication. Re-phosphorylation of TRF2 at Ser365 outside of S phase is required to release RTEL1 from telomeres, which not only protects t-loops from promiscuous unwinding and inappropriate activation of ATM, but also counteracts replication conflicts at DNA secondary structures that arise within telomeres and across the genome. Hence, a phospho-switch in TRF2 coordinates the assembly and disassembly of t-loops during the cell cycle, which protects telomeres from replication stress and an unscheduled DNA damage response.


Assuntos
Ciclo Celular , Quinases Ciclina-Dependentes/metabolismo , Fosfosserina/metabolismo , Telômero/metabolismo , Proteína 2 de Ligação a Repetições Teloméricas/química , Proteína 2 de Ligação a Repetições Teloméricas/metabolismo , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , DNA/biossíntese , DNA/química , DNA/metabolismo , Quebras de DNA de Cadeia Dupla , Dano ao DNA , DNA Helicases/metabolismo , Reparo do DNA , Replicação do DNA , Fibroblastos , Genoma/genética , Células HEK293 , Humanos , Camundongos , Mutação , Fenótipo , Monoéster Fosfórico Hidrolases/metabolismo , Fosforilação , Antígeno Nuclear de Célula em Proliferação/metabolismo , Fase S , Complexo Shelterina , Telomerase/metabolismo , Telômero/genética , Proteínas de Ligação a Telômeros/química , Proteínas de Ligação a Telômeros/metabolismo , Proteína 2 de Ligação a Repetições Teloméricas/genética
5.
Nucleic Acids Res ; 51(14): 7376-7391, 2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37377435

RESUMO

53BP1 is primarily known as a key regulator in DNA double-strand break (DSB) repair. However, the mechanism of DSB-triggered cohesin modification-modulated chromatin structure on the recruitment of 53BP1 remains largely elusive. Here, we identified acetyltransferase ESCO2 as a regulator for DSB-induced cohesin-dependent chromatin structure dynamics, which promotes 53BP1 recruitment. Mechanistically, in response to DNA damage, ATM phosphorylates ESCO2 S196 and T233. MDC1 recognizes phosphorylated ESCO2 and recruits ESCO2 to DSB sites. ESCO2-mediated acetylation of SMC3 stabilizes cohesin complex conformation and regulates the chromatin structure at DSB breaks, which is essential for the recruitment of 53BP1 and the formation of 53BP1 microdomains. Furthermore, depletion of ESCO2 in both colorectal cancer cells and xenografted nude mice sensitizes cancer cells to chemotherapeutic drugs. Collectively, our results reveal a molecular mechanism for the ATM-ESCO2-SMC3 axis in DSB repair and genome integrity maintenance with a vital role in chemotherapy response in colorectal cancer.


Assuntos
Proteínas de Ciclo Celular , Proteína 1 de Ligação à Proteína Supressora de Tumor p53 , Animais , Camundongos , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Cromatina , Neoplasias Colorretais/metabolismo , Dano ao DNA , Reparo do DNA , Camundongos Nus , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/genética , Humanos , Linhagem Celular Tumoral , Coesinas
6.
Proc Natl Acad Sci U S A ; 119(11): e2113074119, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35254894

RESUMO

SignificanceWith obesity on the rise, there is a growing appreciation for intracellular lipid droplet (LD) regulation. Here, we show how saturated fatty acids (SFAs) reduce fat storage-inducing transmembrane protein 2 (FIT2)-facilitated, pancreatic ß cell LD biogenesis, which in turn induces ß cell dysfunction and death, leading to diabetes. This mechanism involves direct acylation of FIT2 cysteine residues, which then marks the FIT2 protein for endoplasmic reticulum (ER)-associated degradation. Loss of ß cell FIT2 and LDs reduces insulin secretion, increases intracellular ceramides, stimulates ER stress, and exacerbates diet-induced diabetes in mice. While palmitate and stearate degrade FIT2, unsaturated fatty acids such as palmitoleate and oleate do not, results of which extend to nutrition and diabetes.


Assuntos
Diabetes Mellitus/etiologia , Diabetes Mellitus/metabolismo , Células Secretoras de Insulina/metabolismo , Gotículas Lipídicas/metabolismo , Metabolismo dos Lipídeos , Proteínas de Membrana/genética , Animais , Linhagem Celular , Estresse do Retículo Endoplasmático , Ácidos Graxos/metabolismo , Glucose/metabolismo , Intolerância à Glucose , Proteínas de Membrana/metabolismo , Camundongos , Mutação , Palmitatos/metabolismo , Estearatos/metabolismo
7.
Nano Lett ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856668

RESUMO

Cell membrane-based nanovesicles (CMNVs) play pivotal roles in biomolecular transportation in living organisms and appear as attractive bioinformed nanomaterials for theranostic applications. However, the current surface-engineering technologies are limited in flexibility and orthogonality, making it challenging to simultaneously display multiple different ligands on the CMNV surface in a precisely controlled manner. Here, we developed a DNA scaffold-programmed approach to orthogonally engineer CMNVs with versatile ligands. The designed DNA scaffolds can rapidly anchor onto the CMNV surface, and their unique sequences and hybridized properties enable independent control of the loading of multiple different types of biomolecules on the CMNVs. As a result, the orthogonal engineering of CMNVs with a renal targeted peptide and a therapeutic protein at controlled ratios demonstrated an enhanced renal targeting and repair potential in vivo. This study highlights that a DNA scaffold-programmed platform can provide a potent means for orthogonal and flexible surface engineering of CMNVs for diverse therapeutic purposes.

8.
J Neurosci ; 43(47): 8043-8057, 2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-37722850

RESUMO

The malignant brain cancer glioblastoma (GBM) contains groups of highly invasive cells that drive tumor progression as well as recurrence after surgery and chemotherapy. The molecular mechanisms that enable these GBM cells to exit the primary mass and disperse throughout the brain remain largely unknown. Here we report using human tumor specimens and primary spheroids from male and female patients that glial cell adhesion molecule (GlialCAM), which has normal roles in brain astrocytes and is mutated in the developmental brain disorder megalencephalic leukoencephalopathy with subcortical cysts (MLC), is differentially expressed in subpopulations of GBM cells. High levels of GlialCAM promote cell-cell adhesion and a proliferative GBM cell state in the tumor core. In contrast, GBM cells with low levels of GlialCAM display diminished proliferation and enhanced invasion into the surrounding brain parenchyma. RNAi-mediated inhibition of GlialCAM expression leads to activation of proinvasive extracellular matrix adhesion and signaling pathways. Profiling GlialCAM-regulated genes combined with cross-referencing to single-cell transcriptomic datasets validates functional links among GlialCAM, Mlc1, and aquaporin-4 in the invasive cell state. Collectively, these results reveal an important adhesion and signaling axis comprised of GlialCAM and associated proteins including Mlc1 and aquaporin-4 that is critical for control of GBM cell proliferation and invasion status in the brain cancer microenvironment.SIGNIFICANCE STATEMENT Glioblastoma (GBM) contains heterogeneous populations of cells that coordinately drive proliferation and invasion. We have discovered that glial cell adhesion molecule (GlialCAM)/hepatocyte cell adhesion molecule (HepaCAM) is highly expressed in proliferative GBM cells within the tumor core. In contrast, GBM cells with low levels of GlialCAM robustly invade into surrounding brain tissue along blood vessels and white matter. Quantitative RNA sequencing identifies various GlialCAM-regulated genes with functions in cell-cell adhesion and signaling. These data reveal that GlialCAM and associated signaling partners, including Mlc1 and aquaporin-4, are key factors that determine proliferative and invasive cell states in GBM.


Assuntos
Aquaporinas , Glioblastoma , Feminino , Humanos , Masculino , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Proteínas de Ciclo Celular/metabolismo , Glioblastoma/metabolismo , Glioblastoma/patologia , Proteínas de Membrana/metabolismo , Microambiente Tumoral , Proliferação de Células , Invasividade Neoplásica
9.
Small ; 20(10): e2305594, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37919857

RESUMO

Diabetic alveolar bone defect (DABD) causes persistent bacterial infection, prolonged inflammation, and delayed bone healing, making it a considerable clinical challenge. In this study, by integrating silver nanoclusters (AgNCs) and M2 macrophage-derived extracellular vesicles (M2EVs), a multifunctional DNA-based hydrogel, called Agevgel, is developed with antibacterial, anti-inflammatory, immunomodulatory, and osteogenic properties to promote DABD rebuilding. AgNCs are tightly embedded into the DNA scaffolds and exhibit effective anti-bacterial activity, while immunomodulatory M2EVs are encapsulated within the shape-variable DNA scaffolds and exhibit potent anti-inflammatory and osteogenic properties. The results reveal that Agevgel effectively prolongs the local retention time and bioactivity of M2EVs in vivo. In particular, the sustained release of M2EVs can last for at least 7 days when applying Agevgel to DABD. Compared to free M2EVs or Aggel (AgNCs encapsulated within the DNA hydrogel) treatments, the Agevgel treatment accelerates the defect healing rate of alveolar bone and dramatically improves the trabecular architecture. Mechanistically, Agevgel plays a key role in regulating macrophage polarization and promoting the expression of proliferative and osteogenic factors. In summary, Agevgel provides a comprehensive treatment strategy for DABD with a great clinical translational value, highlighting the application of DNA hydrogels as an ideal bioscaffolds for periodontal diseases.


Assuntos
Diabetes Mellitus , Procedimentos de Cirurgia Plástica , Hidrogéis , Cicatrização , Antibacterianos , DNA , Anti-Inflamatórios
10.
Arch Microbiol ; 206(7): 335, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953983

RESUMO

Salmonella is considered as one of the most common zoonotic /foodborne pathogens in the world. The application of bacteriophages as novel antibacterial agents in food substrates has become an emerging strategy. Bacteriophages have the potential to control Salmonella contamination.We have isolated and characterized a broad-spectrum Salmonella phage, SP154, which can lyse 9 serotypes, including S. Enteritidis, S. Typhimurium, S. Pullorum, S. Arizonae, S. Dublin, S. Cholerasuis, S. Chester, S. 1, 4, [5], 12: i: -, and S. Derby, accounting for 81.9% of 144 isolates. SP154 showed a short latent period (40 min) and a high burst size (with the first rapid burst size at 107 PFUs/cell and the second rapid burst size at approximately 40 PFUs/cell). Furthermore, SP154 activity has higher survival rates across various environmental conditions, including pH 4.0-12.0 and temperatures ranging from 4 to 50 °C for 60 min, making it suitable for diverse food processing and storage applications. Significant reductions in live Salmonella were observed in different foods matrices such as milk and chicken meat, with a decrease of up to 1.9 log10 CFU/mL in milk contamination and a 1 log10 CFU/mL reduction in chicken meat. Whole genome sequencing analysis revealed that SP154 belongs to the genus Ithacavirus, subfamily Humphriesvirinae, within the family Schitoviridae. Phylogenetic analysis based on the terminase large subunit supported this classification, although an alternate tree using the tail spike protein gene suggested affiliation with the genus Kuttervirus, underscoring the limitations of relying on a single gene for phylogenetic inference. Importantly, no virulence or antibiotic resistance genes were detected in SP154. Our research highlights the potential of using SP154 for biocontrol of Salmonella in the food industry.


Assuntos
Microbiologia de Alimentos , Genoma Viral , Fagos de Salmonella , Salmonella , Sequenciamento Completo do Genoma , Fagos de Salmonella/genética , Fagos de Salmonella/isolamento & purificação , Fagos de Salmonella/classificação , Fagos de Salmonella/fisiologia , Animais , Salmonella/virologia , Salmonella/genética , Salmonella/classificação , Salmonella/isolamento & purificação , Galinhas , Leite/microbiologia , Leite/virologia , Carne/microbiologia , Carne/virologia , Filogenia
11.
BMC Vet Res ; 20(1): 187, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730463

RESUMO

BACKGROUND: Porcine epidemic diarrhea virus (PEDV), a type of coronavirus, is one of the main pathogens that can infect pigs of all ages. It causes diarrhea and acute death of newborn piglets, resulting in massive economic losses to the worldwide swine industry. While vaccination remains the primary approach in combating PEDV, it often fails to address all the challenges posed by the infection, particularly in light of the emergence of evolving mutant strains. Therefore, there is a critical need to identify potent antiviral drugs that can effectively safeguard pigs against PEDV infection. RESULTS: In this study, the antiviral efficacy of SP2509, a specific antagonist of Lysine-specific demethylase 1(LSD1), was evaluated in vitro. The RT-qPCR, Western blot, TCID50, and IFA showed that at a concentration of 1µmol/L, SP2509 significantly inhibited PEDV infection. Additionally, viral life cycle assays showed that SP2509 operates by impeding PEDV internalization and replication rather than attachment and release. Regarding mechanism, in Huh-7 cells, knockdowns LSD1 can suppress PEDV replication. This indicated that the inhibition effect of SP2509 on PEDV largely depends on the activity of its target protein, LSD1. CONCLUSION: Our results in vitro show that SP2509 can inhibit PEDV infection during the internalization and replication stage and revealed a role of LSD1 as a restriction factor for PEDV. These imply that LSD1 might be a target for interfering with the viral infection, and SP2509 could be developed as an effective anti-PEDV agent.


Assuntos
Antivirais , Histona Desmetilases , Vírus da Diarreia Epidêmica Suína , Replicação Viral , Vírus da Diarreia Epidêmica Suína/efeitos dos fármacos , Animais , Antivirais/farmacologia , Replicação Viral/efeitos dos fármacos , Histona Desmetilases/antagonistas & inibidores , Suínos , Chlorocebus aethiops , Doenças dos Suínos/virologia , Doenças dos Suínos/tratamento farmacológico , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Células Vero
12.
BMC Public Health ; 24(1): 1767, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956480

RESUMO

BACKGROUND: Women at middle age are puzzled by a series of menopausal disturbances, can be distressing and considerably affect the personal, social and work lives. We aim to estimate the global prevalence of nineteen menopausal symptoms among middle-aged women by performing a systematic review and meta-analysis. METHODS: Comprehensive search was performed in multiple databases from January, 2000 to March, 2023 for relevant studies. Random-effect model with double-arcsine transformation was used for data analysis. RESULTS: A total of 321 studies comprised of 482,067 middle-aged women were included for further analysis. We found varied prevalence of menopausal symptoms, with the highest prevalence of joint and muscular discomfort (65.43%, 95% CI 62.51-68.29) and lowest of formication (20.5%, 95% CI 13.44-28.60). Notably, South America shared dramatically high prevalence in a sort of menopausal symptoms including depression and urogenital symptoms. Besides, countries with high incomes (49.72%) had a significantly lower prevalence of hot flashes than those with low (65.93%), lower-middle (54.17%), and upper-middle (54.72%, p < 0.01), while personal factors, such as menopausal stage, had an influence on most menopausal symptoms, particularly in vaginal dryness. Prevalence of vagina dryness in postmenopausal women (44.81%) was 2-fold higher than in premenopausal women (21.16%, p < 0.01). Furthermore, a remarkable distinction was observed between body mass index (BMI) and prevalence of sleep problems, depression, anxiety and urinary problems. CONCLUSION: The prevalence of menopausal symptoms affected by both social and personal factors which calls for attention from general public.


Assuntos
Fogachos , Menopausa , Humanos , Feminino , Menopausa/fisiologia , Prevalência , Pessoa de Meia-Idade , Fogachos/epidemiologia , Saúde Global/estatística & dados numéricos
13.
BMC Public Health ; 24(1): 187, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-38225595

RESUMO

BACKGROUND: Magnesium (Mg) is both an essential macro-element and a known catalyst, and it plays a vital role in various physiological activities and mechanisms in relation to chronic kidney disease (CKD). However, epidemiological evidence involving this is limited and not entirely consistent. This study aims to explore the association of serum Mg concentrations with the risk of CKD among general Chinese adults. METHODS: A total of 8,277 Chinese adults were included in the wave of 2009 from the China Health and Nutrition Survey (CHNS). The primary outcome was the risk of CKD, which was defined as the estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2. Multivariable logistic regression model was used to examine the relationship of serum Mg concentrations with the risk of CKD. RESULTS: Included were 8,277 individuals, with an overall CKD prevalence of 11.8% (n = 977). Compared with the first quartile of serum Mg, the multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for participants in the second, third, and fourth quartiles of serum Mg were 0.74 (0.58, 0.93), 0.87 (0.69, 1.11) and 1.29 (1.03, 1.61), respectively. Similar results were observed in our several sensitivity analyses. Restricted cubic spline analysis demonstrated a nonlinear (similar "J"-shaped) association between serum Mg concentrations and the risk of CKD (Pnonlinearity <0.001), with a threshold at around a serum Mg value of 2.2 mg/dL. CONCLUSIONS: Our results suggested a similar "J"-shaped association between serum Mg concentration and the risk of CKD among Chinese adults. Further large prospective studies are needed to verify these findings.


Assuntos
Magnésio , Insuficiência Renal Crônica , Adulto , Humanos , Estudos Transversais , Insuficiência Renal Crônica/epidemiologia , Taxa de Filtração Glomerular , Inquéritos Epidemiológicos , Fatores de Risco
14.
Ecotoxicol Environ Saf ; 269: 115747, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38070415

RESUMO

Microplastics (MPs) are global environmental pollutants with potential toxicity concerns, and their effects on the reproductive system have attracted increasing attention. This study investigated the interaction between MPs and mammalian biomolecules, focusing on the relationship between the testosterone adsorption behavior of MPs and male reproductive health. The adsorption capacity of different types of MPs for testosterone was evaluated in vitro experiments. Polyamide (PA)-MPs exhibited stronger adsorption, while polymethyl methacrylate (PMMA)-MPs displayed the weakest adsorption. Sorption equilibrium between PA-MPs and testosterone was achieved within 6 h, fitting the Pseudo-2nd-order model and Langmuir isotherm. The effects of MPs on male reproduction in mice was determined in vivo experiments. Male mice were treated with 0.1 and 0.5 mg/d PA-MPs/PMMA-MPs by gavage once per day for 28 days. The results showed that only 0.5 mg/d PA-MP exposure induced decreased serum testosterone levels, increased testicular testosterone levels compared to the control, and more severe damage to seminiferous tubule structure, sperm motility and sperm morphology compared to the PMMA-MPs group. Meanwhile, PA-MPs could reduce intracellular nuclear translocation of androgen receptor (AR) mediated by testosterone, while PMMA-MPs had no impact. The study revealed that PA-MP adsorption reduced testosterone bioavailability and caused sperm quality to decline, offering new insights into the combined toxicity mechanism of MPs in male mammals.


Assuntos
Microplásticos , Poluentes Químicos da Água , Masculino , Animais , Camundongos , Microplásticos/toxicidade , Plásticos/toxicidade , Plásticos/química , Nylons , Testosterona , Adsorção , Disponibilidade Biológica , Polimetil Metacrilato , Saúde Reprodutiva , Sêmen/química , Motilidade dos Espermatozoides , Poluentes Químicos da Água/análise , Mamíferos
15.
Ecotoxicol Environ Saf ; 272: 116075, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38325273

RESUMO

Although animal studies have shown the reproductive toxicity of vanadium, less is known about its effects on semen quality in humans. Among 1135 healthy men who were screened as potential semen donors, we investigated the relationships of semen quality with urinary and seminal plasma vanadium levels via inductively coupled plasma-mass spectrometry (ICP-MS). Spearman rank correlation tests and linear regression models were used to assess the correlations between average urinary and within-individual pooled seminal plasma vanadium concentrations (n = 1135). We utilized linear mixed-effects models to evaluate the associations of urinary and seminal plasma vanadium levels (n = 1135) with repeated sperm quality parameters (n = 5576). Seminal plasma vanadium concentrations were not significantly correlated with urinary vanadium concentrations (r = 0.03). After adjusting for possible confounders, we observed inverse relationships of within-individual pooled seminal plasma vanadium levels with total count, semen volume, and sperm concentration (all P values for trend < 0.05). Specifically, subjects in the highest (vs. lowest) tertile of seminal plasma vanadium concentrations had - 11.3% (-16.4%, -5.9%), - 11.1% (-19.1%, -2.4%), and - 20.9% (-29.0%, -11.8%) lower sperm volume, concentration, and total count, respectively; moreover, urinary vanadium levels appeared to be negatively associated with sperm motility. These relationships showed monotonically decreasing dose-response patterns in the restricted cubic spline analyses. Our results demonstrated a poor correlation between urinary and seminal plasma levels of vanadium, and elevated vanadium concentrations in urine and seminal plasma may be adversely related to male semen quality.


Assuntos
Análise do Sêmen , Sêmen , Animais , Masculino , Humanos , Sêmen/química , Vanádio/toxicidade , Vanádio/análise , Motilidade dos Espermatozoides , Contagem de Espermatozoides , Espermatozoides/fisiologia
16.
Genes Dev ; 30(6): 687-99, 2016 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-26966246

RESUMO

We identified Mte1 (Mph1-associated telomere maintenance protein 1) as a multifunctional regulator of Saccharomyces cerevisiae Mph1, a member of the FANCM family of DNA motor proteins important for DNA replication fork repair and crossover suppression during homologous recombination. We show that Mte1 interacts with Mph1 and DNA species that resemble a DNA replication fork and the D loop formed during recombination. Biochemically, Mte1 stimulates Mph1-mediated DNA replication fork regression and branch migration in a model substrate. Consistent with this activity, genetic analysis reveals that Mte1 functions with Mph1 and the associated MHF complex in replication fork repair. Surprisingly, Mte1 antagonizes the D-loop-dissociative activity of Mph1-MHF and exerts a procrossover role in mitotic recombination. We further show that the influence of Mte1 on Mph1 activities requires its binding to Mph1 and DNA. Thus, Mte1 differentially regulates Mph1 activities to achieve distinct outcomes in recombination and replication fork repair.


Assuntos
RNA Helicases DEAD-box/metabolismo , Replicação do DNA/fisiologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Ligação a Telômeros/metabolismo , RNA Helicases DEAD-box/genética , Reparo do DNA/genética , Epistasia Genética , Deleção de Genes , Regulação Fúngica da Expressão Gênica , Mitose , Ligação Proteica , Multimerização Proteica , Estrutura Terciária de Proteína , Proteínas de Saccharomyces cerevisiae/genética
17.
World J Microbiol Biotechnol ; 40(2): 78, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38253730

RESUMO

Efforts to curtail the escalating health threat posed by methicillin-resistant Staphylococcus aureus (MRSA), a formidable superbug, necessitate the development of innovative treatment strategies. Leveraging potential compounds from natural sources in tandem with antibiotics has emerged as a promising approach against MRSA. These strategies should enhance the antibiotic efficacy, reduce dosage and toxicity, and bypass MRSA resistance. In this study, we used a checkerboard assay to illustrate the significant synergistic anti-MRSA effect of shikimic acid (SA), a naturally occurring compound, and ceftiofur (CF). Time-kill curves further revealed that a combination of 1/4 of the minimum inhibitory concentration (MIC) of SA and 1/8 MIC of the sodium CF eradicated MRSA within 2 h, with no noticeable toxicity observed with these concentrations. In vivo experiments confirmed that this combination therapy demonstrated robust antimicrobial activity against MRSA-induced bacteremia in mice, significantly reducing bacterial loads in the kidneys, liver, and spleen, attenuating inflammatory cell infiltration, and alleviating pathological damage. This study not only offers a compelling strategy, capitalizing on the synergistic potential of SA and CF, to rapidly address antibiotic resistance but also contributes significantly to the refinement of antimicrobial therapeutic strategies.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Animais , Camundongos , Ácido Chiquímico/farmacologia , Cefalosporinas/farmacologia , Antibacterianos/farmacologia
18.
Cancer ; 129(14): 2201-2213, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37016732

RESUMO

BACKGROUND: Selinexor (KPT-330) is a potent inhibitor of exportin 1 (XPO1), in turn inhibiting tumor growth. Selinexor enhances the antitumor efficacy of eribulin in triple-negative breast cancer (TNBC) in vitro and in vivo. Given the unmet medical need in TNBC and sarcoma, the authors explored the safety and efficacy of this combination. METHODS: The authors conducted a phase 1b trial of combined selinexor and eribulin using a 3 + 3 dose-escalation design in patients who had advanced solid tumors and in those who had TNBC in a dose-expansion cohort. RESULTS: Patients with TNBC (N = 19), sarcoma (N = 9), and other cancers (N = 3) were enrolled in the dose-escalation cohort (N = 10) and in the dose-expansion cohort (N = 21). The median number lines of prior therapy received was four (range, from one to seven prior lines). The most common treatment-related adverse events for selinexor were nausea (77%), leukopenia (77%), anemia (68%), neutropenia (68%), and fatigue (48%). One dose-limiting toxicity occurred at the first dose level with prolonged grade 3 neutropenia. The recommended phase 2 dose was 80 mg of selinexor orally once per week and 1 mg/m2 eribulin on days 1 and 8 intravenously every 3 weeks. The objective response rate (ORR) was 10% in three patients. In the dose-escalation cohort, the ORR was 10%, whereas six patients with had stable disease. In the TNBC dose-expansion cohort (n = 18), ORR was 11%, and there were two confirmed partial responses with durations of 10.8 and 19.1 months (ongoing). CONCLUSIONS: Selinexor and eribulin had an acceptable toxicity profile and modest overall efficacy with durable responses in select patients. PLAIN LANGUAGE SUMMARY: Effective therapies for advanced, triple-negative breast cancer and sarcoma represent an unmet need. Exportin 1 is associated with the transport of cancer-related proteins. Preclinical studies have demonstrated tumor growth inhibition and enhanced tumor sensitivity in patients who receive selinexor combined with eribulin. In this phase 1b study, the authors evaluated the safety profile and clinical activity of the combination of selinexor, a potent oral inhibitor of exportin 1, and eribulin in patients with advanced cancers enriched for triple-negative breast cancer or sarcoma. The combination was well tolerated; most adverse events were mild or moderate, reversible, and managed with dose modifications or growth factor support. The combination of selinexor and eribulin produced an antitumor response, particularly in some patients with triple-negative breast cancer. This work lays the foundation for prospective investigations of the role of selinexor and eribulin in the treatment of triple-negative breast cancer.


Assuntos
Neutropenia , Sarcoma , Neoplasias de Tecidos Moles , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Estudos Prospectivos , Sarcoma/tratamento farmacológico , Neoplasias de Tecidos Moles/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
19.
Oncologist ; 28(4): 368-372, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36200910

RESUMO

Detection of methylation patterns in circulating tumor DNA (ctDNA) can offer a novel approach for cancer diagnostics given the unique signature for each tumor type. We developed a next-generation sequencing (NGS)-based assay targeting 32 CpG sites to detect colorectal cancer-specific ctDNA. NGS was performed on bisulfite-converted libraries and status dichotomization was done using median methylation ratios at all targets. We included plasma samples from patients with metastatic colorectal (n = 20) and non-colorectal cancers (n = 8); and healthy volunteers (n = 4). Median methylation ratio was higher in colorectal cancer compared with non-colorectal cancers (P = .001) and normal donors (P = .005). The assay detected ctDNA in 85% of patients with colorectal cancer at a specificity of 92%. Notably, we were able to detect methylated ctDNA in 75% of patients in whom ctDNA was not detected by other methods. Detection of methylated ctDNA was associated with shorter median progression-free survival compared to non-detection (8 weeks versus 54 weeks; P = .027).


Assuntos
DNA Tumoral Circulante , Neoplasias Colorretais , Neoplasias , Humanos , Metilação , DNA Tumoral Circulante/genética , Biópsia Líquida , Mutação , Biomarcadores Tumorais/genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética
20.
Appl Environ Microbiol ; 89(1): e0106122, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36533928

RESUMO

Avian pathogenic Escherichia coli, a causative agent of avian colibacillosis, has been causing serious economic losses in the poultry industry. The increase in multidrug-resistant isolates and the complexity of the serotypes of this pathogen, especially the recently reported emergence of a newly predominant serogroup of O145, make the control of this disease difficult. To address this challenge, a high-throughput screening approach, called Pan-RV (Reverse vaccinology based on pangenome analysis), is proposed to search for universal protective antigens against the three traditional serogroups and the newly emerged O145. Using this approach, a total of 61 proteins regarded as probable antigens against the four important serogroups were screened from the core genome of 127 Avian pathogenic Escherichia coli (APEC) genomes, and six were verified by Western blots using antisera. Overall, our research will provide a foundation for the development of an APEC subunit vaccine against avian colibacillosis. Given the exponential growth of whole-genome sequencing (WGS) data, our Pan-RV pipeline will make screening of bacterial vaccine candidates inexpensive, rapid, and efficient. IMPORTANCE With the emergence of drug resistance and the newly predominant serogroup O145, the control of Avian pathogenic Escherichia coli is facing a serious challenge; an efficient immunological method is urgently needed. Here, for the first time, we propose a high-throughput screening approach to search for universal protective antigens against the three traditional serogroups and the newly emerged O145. Importantly, using this approach, a total of 61 proteins regarded as probable antigens against the four important serogroups were screened, and three were shown to be immunoreactive with all antisera (covering the four serogroups), thereby providing a foundation for the development of APEC subunit vaccines against avian colibacillosis. Further, our Pan-RV pipeline will provide immunological control strategies for pathogens with complex and variable genetic backgrounds such as Escherichia coli and will make screening of bacterial vaccine candidates more inexpensive, rapid, and efficient.


Assuntos
Infecções por Escherichia coli , Vacinas contra Escherichia coli , Doenças das Aves Domésticas , Animais , Escherichia coli/genética , Sorogrupo , Infecções por Escherichia coli/prevenção & controle , Infecções por Escherichia coli/veterinária , Aves Domésticas , Vacinas Bacterianas , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/microbiologia , Galinhas
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