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1.
Int J Antimicrob Agents ; : 107172, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38608845

RESUMO

OBJECTIVES: This study aimed to discover novel antifungals targeting Candida albicans glyceraldehyde-3-phosphate dehydrogenase (CaGAPDH), have an insight into inhibitory mode, and provide evidence supporting CaGAPDH as a target for new antifungals. METHODS: Virtual screening was utilized to discover inhibitors of CaGAPDH. The inhibitory effect on cellular GAPDH was evaluated by determining the levels of ATP, NAD, NADH, etc., as well as examining GAPDH mRNA and protein expression. The role of GAPDH inhibition in C. albicans was supported by drug affinity responsive target stability and overexpression experiments. The mechanism of CaGAPDH inhibition was elucidated by Michaelis-Menten enzyme kinetics and site-specific mutagenesis based on docking. Chemical synthesis was used to produce an improved candidate. Different sources of GAPDH were used to evaluate inhibitory selectivity across species. In vitro and in vivo antifungal tests, along with antibiofilm activity, were carried out to evaluate antifungal potential of GAPDH inhibitors. RESULTS: A natural xanthone was identified as the first competitive inhibitor of CaGAPDH. It demonstrated in vitro anti-C. albicans potential but also caused hemolysis. XP-W, a synthetic side-chain-optimized xanthone, demonstrated a better safety profile, exhibiting a 50-fold selectivity for CaGAPDH over human GAPDH. XP-W also exhibited potent antibiofilm activity and displayed broad-spectrum anti-Candida activities in vitro and in vivo, including multi-azole-resistant C. albicans. CONCLUSION: These results demonstrate for the first time that CaGAPDH is a valuable target for antifungal drug discovery, and XP-W provides a promising lead.

2.
Autophagy ; : 1-34, 2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38442890

RESUMO

Macroautophagy/autophagy is a complex degradation process with a dual role in cell death that is influenced by the cell types that are involved and the stressors they are exposed to. Ferroptosis is an iron-dependent oxidative form of cell death characterized by unrestricted lipid peroxidation in the context of heterogeneous and plastic mechanisms. Recent studies have shed light on the involvement of specific types of autophagy (e.g. ferritinophagy, lipophagy, and clockophagy) in initiating or executing ferroptotic cell death through the selective degradation of anti-injury proteins or organelles. Conversely, other forms of selective autophagy (e.g. reticulophagy and lysophagy) enhance the cellular defense against ferroptotic damage. Dysregulated autophagy-dependent ferroptosis has implications for a diverse range of pathological conditions. This review aims to present an updated definition of autophagy-dependent ferroptosis, discuss influential substrates and receptors, outline experimental methods, and propose guidelines for interpreting the results.Abbreviation: 3-MA:3-methyladenine; 4HNE: 4-hydroxynonenal; ACD: accidentalcell death; ADF: autophagy-dependentferroptosis; ARE: antioxidant response element; BH2:dihydrobiopterin; BH4: tetrahydrobiopterin; BMDMs: bonemarrow-derived macrophages; CMA: chaperone-mediated autophagy; CQ:chloroquine; DAMPs: danger/damage-associated molecular patterns; EMT,epithelial-mesenchymal transition; EPR: electronparamagnetic resonance; ER, endoplasmic reticulum; FRET: Försterresonance energy transfer; GFP: green fluorescent protein;GSH: glutathione;IF: immunofluorescence; IHC: immunohistochemistry; IOP, intraocularpressure; IRI: ischemia-reperfusion injury; LAA: linoleamide alkyne;MDA: malondialdehyde; PGSK: Phen Green™ SK;RCD: regulatedcell death; PUFAs: polyunsaturated fatty acids; RFP: red fluorescentprotein;ROS: reactive oxygen species; TBA: thiobarbituricacid; TBARS: thiobarbituric acid reactive substances; TEM:transmission electron microscopy.

3.
Nat Cell Biol ; 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424270

RESUMO

Ferroptosis, an intricately regulated form of cell death characterized by uncontrolled lipid peroxidation, has garnered substantial interest since this term was first coined in 2012. Recent years have witnessed remarkable progress in elucidating the detailed molecular mechanisms that govern ferroptosis induction and defence, with particular emphasis on the roles of heterogeneity and plasticity. In this Review, we discuss the molecular ecosystem of ferroptosis, with implications that may inform and enable safe and effective therapeutic strategies across a broad spectrum of diseases.

4.
Pediatr Blood Cancer ; 71(2): e30772, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37974392

RESUMO

BACKGROUND: The prognosis of pediatric Epstein-Barr virus (EBV)-associated hemophagocytic lymphohistiocytosis (EBV-HLH) varies. This study aimed to identify high-risk children early. PROCEDURE: Data from 264 children (0-14 years of age), diagnosed with EBV-HLH at six centers in China between January 2016 and December 2021, were analyzed. Patients were randomly divided into derivation (n = 185) and verification (n = 79) cohorts. A Cox regression model was used to explore risk predictors and establish a prognostic scoring system for death events that occurred during the follow-up period. RESULTS: Chronic active EBV infection (CAEBV) history (hazard ratio [HR] 1.82 [95% confidence interval, CI: 1.02-3.26]; p = .0441), plasma EBV-DNA more than 104  copies/mL (HR 2.89 [95% CI: 1.62-5.16]; p = .0003), pulmonary infection (HR 2.24 [95% CI: 1.06-4.75]; p = .0353), digestive tract hemorrhage (HR 2.55 [95% CI: 1.35-4.82]; p = .0041), and hypoxemia (HR 3.95 [95% CI: 2.15-7.26]; p < .0001) were independent risk factors. Accordingly, the CAEBV history, plasma EBV-DNA copy number, pulmonary infection hemorrhage of digestive tract, hypoxemia prognostic scoring system (CEPHO-PSS) were developed, which separated patients into low- (0-1 points), middle- (2-3 points), and high- (4-8 points) risk groups. Survival curves for the three groups exhibited statistically significant differences (p < .0001). Internal and external verification of CEPHO-PSS was performed using receiver operating characteristic (ROC) and calibration curves in the derivation and verification cohorts, respectively, confirming good accuracy and applicability. CONCLUSIONS: The CEPHO-PSS identified three risk groups with statistically significant differences in survival curves. It was based on the baseline characteristics, and can give clinicians a convenient check for risk prediction.


Assuntos
Infecções por Vírus Epstein-Barr , Linfo-Histiocitose Hemofagocítica , Humanos , Criança , Herpesvirus Humano 4/genética , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/diagnóstico , Prognóstico , Estudos Retrospectivos , DNA , Hemorragia , Hipóxia
5.
Front Vet Sci ; 10: 1289546, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38099001

RESUMO

Pu-erh tea pomace (PTP), a solid substance after extracting functional substances or steeping tea, is rich in crude protein, and crude fiber, and could be used as considerable bioactive substances in animal production. However, its application as poultry feed and its role in regulating the characteristics of gut microorganisms is unclear. The present study investigated the effects of PTP on growth performance and gut microbes of chicken. A total of 144 Chahua chickens No. 2 were individually housed and divided into three groups which were fed diets containing 0% (CK), 1% PTP (T1), and 2% PTP (T2), respectively. The serum and cecum contents were collected after slaughter for analysis. The results indicated that growth performance and carcass traits were not affected by the PTP content. Serum total triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) levels in the T1 and T2 groups were significantly lower than in the CK group (p < 0.05). The gut microbiota α-diversity in the T2 group was significantly lower than in the CK group (p < 0.05). Based on partial least squares-discriminant analysis (PLS-DA), we observed significant segregation in gut bacterial communities among the groups. At the phylum level, Bacteroidetes and Firmicutes were dominant in the cecum, occupying about 85% of the cecum flora. The relative abundance of Bacteroidetes tended to increase. At the genus level, the relative abundance of Bacteroides is the highest in the CK、T1 and T2 groups. The relative abundances of Bacteroides and Prevotellaceae_UCG-001 microorganisms in the T2 group were significantly higher than in the CK group (p < 0.05). However, the relative abundance of CHKCI001 microorganisms in the T2 group was significantly lower compared to the CK group (p < 0.05). TG content was significantly positively correlated with CHKCI001 relative abundance, and significantly negatively correlated with Prevotellaceae_UCG-001 relative abundance (p < 0.05). Moreover, the LDL-C content was significantly positively correlated with CHKCI001 relative abundance (p < 0.05). In conclusion, PTP could decrease the cholesterol levels in the blood by improving the composition of gut microbiota, which provides a reference for the application of PTP in the poultry industry.

6.
Hum Vaccin Immunother ; 19(3): 2268392, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37964617

RESUMO

In China, the coverage rate of influenza vaccination among the general population is significantly lower than that of high-income countries, with only 2.46% of the population vaccinated. Preschool-aged children are particularly susceptible to influenza viruses, yet the factors that influence parents' willingness to vaccinate their children are not well understood. To address this research gap, we developed a theoretical model grounded in the Unified Theory of Acceptance and Use of Technology (UTAUT), which explores six key factors influencing parental self-reported uptake of influenza vaccination in preschool children: performance expectancy, effort expectancy, social influence, facilitating conditions, knowledge, and behavioral intention. We collected data from 872 parents of children in five major cities in China and employed structural equation modeling to examine the significance of the theoretical model and explore the potential moderating effects of demographic variables on path relationships. Our analysis revealed that several positive factors influenced parents' intention of influenza vaccination for preschool children, including effort expectancy (ß = 0.38), social influence (ß = 0.17), and knowledge (ß = 0.52). Facilitating conditions (ß = 0.34), knowledge (ß = 0.40), and behavioral intention (ß = 0.34) were found to be associated with self-reported uptake. Furthermore, we observed significant moderating effects of the child's gender and age, as well as the guardian's category and income, on the theoretical models. Parents' willingness to vaccinate preschool children against influenza is influenced by both psychological and demographic variables. Further studies are needed to determine if these relationships persist over time and across different regions.


Assuntos
COVID-19 , Vacinas contra Influenza , Influenza Humana , Humanos , Pré-Escolar , Autorrelato , Influenza Humana/prevenção & controle , Pandemias , Pais/psicologia , Vacinação/psicologia , Intenção , Conhecimentos, Atitudes e Prática em Saúde
7.
Molecules ; 28(22)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38005214

RESUMO

Distiller's grains (DGs) are solid mixtures that remain after the production of alcoholic beverages. A large amount of DGs is produced each year during the brewing process. Currently, they are mostly used as a feedstock or substrate in the feed industry. However, the lack of a comprehensive understanding of the chemical composition of DGs is a major constraint on their further development and application for high-value-added usages. Some studies were published on the bioactive constituents of DGs in several different types of journals. Data were therefore collated to provide a comprehensive overview of these natural products. DGs are rich in phenols, phytosterols, and fatty acids, in addition to general lipid and protein constituents. These compounds and their related extracts possess diverse biological activities, including antioxidant, anti-inflammatory, and anti-hyperglycaemic effects. We hope that this review will provide research incentives for the further development and utilisation of DGs to develop high-value-added products.


Assuntos
Bebidas Alcoólicas , Proteínas , Antioxidantes/farmacologia , Grão Comestível , Estruturas Vegetais , Ração Animal
8.
Front Pharmacol ; 14: 1247253, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37808193

RESUMO

Background: Unfractionated heparin (UFH) and low-molecular-weight heparin (LMWH) are commonly used anticoagulants for the management of arterial and venous thromboses. However, it is crucial to be aware that LMWH can, in rare cases, lead to a dangerous complication known as heparin-induced thrombocytopenia (HIT). The objective of this study was to evaluate the pharmacovigilance and clinical features of HIT associated with LMWH, as well as identify treatment strategies and risk factors to facilitate prompt management. Methods: We extracted adverse event report data from the FDA Adverse Event Reporting System (FAERS) database for pharmacovigilance assessment. Case reports on LMWH-induced thrombocytopenia dated up to 20 March 2023 were collected for retrospective analysis. Results: Significantly elevated reporting rates of HIT were shown in adverse event (AE) data of LMWHs in the FAERS database, while tinzaparin had a higher proportional reporting ratio (PRR) and reporting odds ratio (ROR) than other LMWHs, indicating a greater likelihood of HIT. Case report analysis indicated that a total of 43 patients showed evidence of LMWH-induced thrombocytopenia with a median onset time of 8 days. Almost half of the events were caused by enoxaparin. LMWHs were mainly prescribed for the treatment of embolism and thromboprophylaxis of joint operation. Patients with a history of diabetes or surgery appeared to be more susceptible to HIT. Clinical symptoms were mostly presented as thrombus, skin lesion, and dyspnea. Almost 90% of the patients experienced a platelet reduction of more than 50% and had a Warkentin 4T score of more than 6, indicating a high likelihood of HIT. In all patients, LMWHs that were determined to be the cause were promptly withdrawn. Following the discontinuation of LMWHs, almost all patients were given alternative anticoagulants and eventually achieved recovery. Conclusion: LMWH-induced thrombocytopenia is rare but serious, with increased risk in patients with diabetes or a surgical history. Prompt recognition and management are crucial for the safe use of LMWHs.

9.
Autophagy ; : 1-20, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37768124

RESUMO

ABBREVIATIONS: ACSL: acyl-CoA synthetase long chain family; DISC: death-inducing signaling complex; DAMPs: danger/damage-associated molecular patterns; Dtgn: dispersed trans-Golgi network; FAR1: fatty acyl-CoA reductase 1; GPX4: glutathione peroxidase 4; LPCAT3: lysophosphatidylcholine acyltransferase 3; LPS: lipopolysaccharide; MUFAs: monounsaturated fatty acids; MOMP: mitochondrial outer membrane permeabilization; MLKL, mixed lineage kinase domain like pseudokinase; oxPAPC: oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine; OxPCs: oxidized phosphatidylcholines; PUFAs: polyunsaturated fatty acids; POR: cytochrome p450 oxidoreductase; PUFAs: polyunsaturated fatty acids; RCD: regulated cell death; RIPK1: receptor interacting serine/threonine kinase 1; SPHK1: sphingosine kinase 1; SOAT1: sterol O-acyltransferase 1; SCP2: sterol carrier protein 2; SFAs: saturated fatty acids; SLC47A1: solute carrier family 47 member 1; SCD: stearoyl-CoA desaturase; VLCFA: very long chain fatty acids.

10.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 48(7): 1105-1112, 2023 Jul 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37724414

RESUMO

Leukemia complicated with Mucor and Aspergillus coinfection is very rare, which is difficult to diagnose, and life-threatening. The clinical characteristics, diagnosis and treatment in a child with acute myeloid leukemia (AML), who developed mucormycosis and aspergillus coinfection after chemotherapy, was reported. This case was a 12-year-old boy who presented with fever and cough during chemotherapy. Rhizomucor pusillus and Aspergillus flavus were detected in his blood, cerebrospinal fluid and alveolar lavage fluid by metagenomic next-generation sequencing (mNGS). Amphotericin B, posaconazole, and voriconazole were successively used for antifungal therapy. Skin debridement, bronchoalveolar lavage and local perfusion under bronchoscopy were performed. The infection of children was well controlled. The clinical manifestations of leukemia with mixed fungal infection are non-specific. The disease progresses rapidly and is prone to spread. Early diagnosis and treatment should be carried out. Combined antifungal therapy is recommended, and surgery is helpful to improve the patient's condition.


Assuntos
Aspergilose , Coinfecção , Leucemia , Mucormicose , Masculino , Criança , Humanos , Mucormicose/diagnóstico , Mucormicose/terapia , Coinfecção/diagnóstico , Antifúngicos/uso terapêutico , Aspergilose/diagnóstico , Aspergilose/tratamento farmacológico
11.
Methods Mol Biol ; 2712: 149-156, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37578703

RESUMO

Ferroptosis is a form of regulated cell death that occurs due to abnormal lipid metabolism. Lipids, which have been identified in over 45,000 different molecular species, play essential roles in modulating basic life processes. The process of ferroptosis is highly reliant on various lipid species, with polyunsaturated fatty acids (PUFAs) playing a central role in driving this process. Recent advances in mass spectrometry-based lipidomics have led to a surge in studies on ferroptosis. To explore the mechanism of lipid homeostasis in ferroptosis, the development of lipidomics techniques is critical. Currently, liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-mass spectrometry (GC-MS) are the most widely used analytical techniques in lipidomics. These techniques offer deeper insights into the complex lipid mechanisms that underlie ferroptosis.


Assuntos
Ferroptose , Lipidômica , Cromatografia Líquida/métodos , Lipidômica/métodos , Lipídeos/química , Espectrometria de Massas em Tandem/métodos
12.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(7): 718-725, 2023 Jul 15.
Artigo em Chinês | MEDLINE | ID: mdl-37529954

RESUMO

OBJECTIVES: To explore the value of metagenomic next-generation sequencing (mNGS) in the pathogen identification in children with hematological malignancies complicated with infections. METHODS: A retrospective analysis was conducted on clinical data and pathogenic test results of 43 children with hematological malignancies who underwent microbial culture and mNGS due to infections in the Third Xiangya Hospital of Central South University between June 2020 and July 2022. Differences in detection rates and characteristics of pathogenic microorganisms detected by mNGS and microbial culture were compared. RESULTS: A total of 54 specimens were examined, and the overall detection rate of pathogen by mNGS (80%, 43/54) was significantly higher than that by microbial culture (30%, 16/54) (P<0.001). The most commonly detected infection type by mNGS was viral infection, followed by fungal infection combined viral infection, while that by microbial culture was bacterial infection, followed by fungal infection. The detection rate of fungi by mNGS (33%, 18/54) was higher than that by microbial culture (6%, 3/54) (P<0.001). The detection rate of two or more pathogenic microorganisms by mNGS was higher at 48% compared to microbial culture at 9% (P<0.05). The detection rate of two or more types of pathogenic microorganisms by mNGS was also significantly higher at 33% compared to microbial culture at 2% (P<0.05). The most commonly detected bacteria and fungi by mNGS were Pseudomonas aeruginosa and Candida tropicalis, respectively, in peripheral blood, while Streptococcus pneumoniae and Pneumocystis jirovecii were most commonly detected in bronchoalveolar lavage fluid. Treatment adjustments based on mNGS results were beneficial for 35% (15/43) of the cases. CONCLUSIONS: mNGS has a higher detection rate than microbial culture and has obvious advantages in diagnosing mixed and fungal infections, making it a useful supplementary diagnostic method to microbial culture.


Assuntos
Neoplasias Hematológicas , Humanos , Criança , Estudos Retrospectivos , Neoplasias Hematológicas/complicações , Sequenciamento de Nucleotídeos em Larga Escala , Líquido da Lavagem Broncoalveolar , Hospitais , Sensibilidade e Especificidade
13.
Br J Clin Pharmacol ; 89(12): 3637-3647, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37548052

RESUMO

AIMS: Methotrexate (MTX) is recognized for its potential to induce hepatotoxicity, commonly manifested by elevated alanine aminotransferase (ALT) levels. However, the quantitative relationship between the pharmacokinetics (PK) of MTX and ALT-based hepatotoxicity remains unclear. This study aimed to develop a semimechanistic PK/pharmacodynamic (PD) model to characterize the MTX-induced hepatotoxicity based on ALT in paediatric patients with acute lymphoid leukaemia. METHODS: A retrospective study was conducted on paediatric patients who received high-dose (3-5 g/m2 ) MTX treatment. MTX concentrations were assessed at 24-h intervals until the concentration dropped below 0.1 µmol/L. ALT concentrations were measured both before and after MTX administration. A population PK model was initially developed, which was later connected to a semimechanistic hepatotoxicity model. RESULTS: The PK model was developed using 354 MTX concentrations obtained from 51 patients, while the PD model was constructed using 379 ALT concentrations collected from 48 patients. The optimal PK model for MTX consisted of a 2-compartment structure, where body surface area served as a covariate for clearance and central volume of distribution. An indirect response model coupled to a liver injury signal transduction model was developed to describe the dynamics of ALT after MTX administration. The drug effect was adequately described by a linear model, exhibiting considerable interoccasion variability for each treatment session. No significant covariates were identified to have an impact on the PD parameters. CONCLUSION: A semimechanistic model was developed to describe ALT-based hepatotoxicity of MTX, and it has the potential to serve as a valuable tool for characterizing drug-induced hepatotoxicity.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Criança , Metotrexato/farmacocinética , Alanina Transaminase , Estudos Retrospectivos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico
14.
Front Nutr ; 10: 1121203, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37545590

RESUMO

Background/aims: Some studies showed that probiotics could improve the composition and structure of gut microbiota. Changes in the gut microbiota may alter bile acid (BAs) composition and kinetics, improving non-alcoholic fatty liver disease (NAFLD). However, it still needs to be clarified how probiotics improve both the metabolism of BAs and NAFLD. This study aimed to reveal the regulatory mechanisms of cholesterol-lowering (CL) probiotics on NAFLD from aspects involved in BA metabolism in FXR gene knockout (FXR-/-) mice. Methods: FXR-/- male mice were randomly divided into three groups based on different interventions for 16 weeks, including normal diet (ND), high-fat diet (HFD), and probiotic intervention in the HFD (HFD+P) group. 16s rDNA sequencing and ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) were utilized to analyze the changes in gut microbiota and fecal bile acids in mice. Results: We found that the intervention of the CL probiotics improved liver lipid deposition and function in HFD-induced NAFLD mice by decreasing the levels of total cholesterol (TC; p = 0.002) and triglyceride (TG; p = 0.001) in serum, as well as suppressing liver inflammation, such as interleukin-1 beta (IL-1ß; p = 0.002) and tumor necrosis factor-alpha (TNF-α; p < 0.0001). 16S rDNA sequencing and metabolomic analyses showed that probiotics effectively reduced the abundance of harmful gut microbiota, such as Firmicutes (p = 0.005), while concomitantly increasing the abundance of beneficial gut microbiota in NAFLD mice, such as Actinobacteriota (p = 0.378), to improve NAFLD. Compared with the ND group, consuming an HFD elevated the levels of total BAs (p = 0.0002), primary BAs (p = 0.017), and secondary BAs (p = 0.0001) in mice feces, while the intervention with probiotics significantly reduced the increase in the levels of fecal total bile acids (p = 0.013) and secondary bile acids (p = 0.017) induced by HFD. Conclusion: The CL probiotics were found to improve liver function, restore microbiota balance, correct an abnormal change in the composition and content of fecal bile acids, and repair the damaged intestinal mucosal barrier in mice with NAFLD, ultimately ameliorating the condition. These results suggested that CL probiotics may be a promising and health-friendly treatment option for NAFLD.

15.
Comp Med ; 73(4): 277-284, 2023 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-37550055

RESUMO

Tree shrews display obvious reproductive cycles, and sexually mature male tree shrews produce little or no sperm with extremely low motility during the nonreproductive season; the mechanism underlying this phenomenon remains unknown. Because testis-specific serine/threonine kinases (TSSK) are specifically expressed in the testis and male germ cells of mammals, we hypothesized that they may have an important role in spermatogenesis or sperm function regulation in tree shrews. In addition, the expression, distribution, subcellular localization, and dynamic changes of TSSK in tree shrew sperm are unclear. Here we show that during the reproductive season, the seminiferous tubules were significantly larger as compared with the nonreproductive season and contained mature sperm and other germ cells. The mRNA expression of Tssk genes in testis was significantly higher than that in other tissues, and the mRNA level in the testis during the reproductive season was significantly higher than that in nonreproductive season. In addition, the mRNA level of Tssk3 in the testis and sperm was significantly higher than that of other members. Specifically, Tssk1 mRNA was distributed in the acrosome and throughout the flagellum of tree shrew sperm, Tssk2 was present in the acrosome, Tssk3 was localized to postacrosomal region and relocated to the main part of the flagellum after capacitation, and Tssk6 was distributed in the acrosome and postacrosomal region. These results indicate that the TSSK are important regulating reproductive function in tree shrews.


Assuntos
Testículo , Tupaia , Masculino , Animais , Testículo/metabolismo , Tupaia/genética , Tupaia/metabolismo , Tupaiidae/genética , Tupaiidae/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Musaranhos/genética , Musaranhos/metabolismo , Estações do Ano , Sêmen/metabolismo , Espermatozoides/metabolismo , Treonina , RNA Mensageiro , Serina
16.
J Am Chem Soc ; 145(29): 16228-16237, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37460135

RESUMO

EGFR tyrosine kinase inhibitors have made remarkable success in targeted cancer therapy. However, therapeutic resistance inevitably occurred and EGFR-targeting therapy has been demonstrated to have limited efficacy or utility in glioblastoma, colorectal cancer, and hepatocellular carcinoma. Therefore, there is a high demand for the development of new targets to inhibit EGFR signaling. Herein, we found that the EGFR oncogene proximal promoter sequence forms a unique type of snap-back loop containing G-quadruplex (G4), which can be targeted by small molecules. For the first time, we determined the NMR solution structure of this snap-back EGFR-G4, a three-tetrad-core, parallel-stranded G4 with naturally occurring flanking residues at both the 5'-end and 3'-end. The snap-back loop located at the 3'-end region forms a stable capping structure through two stacked G-triads connected by multiple potential hydrogen bonds. Notably, the flanking residues are consistently absent in reported snap-back G4s, raising the question of whether such structures truly exist under in vivo conditions. The resolved EGFR-G4 structure has eliminated the doubt and showed distinct structural features that distinguish it from the previously reported snap-back G4s, which lack the flanking residues. Furthermore, we found that the snap-back EGFR-G4 structure is highly stable and can form on an elongated DNA template to inhibit DNA polymerase. The unprecedented high-resolution EGFR-G4 structure has thus contributed a promising molecular target for developing alternative EGFR signaling inhibitors in cancer therapeutics. Meanwhile, the two stacked triads may provide an attractive site for specific small-molecule targeting.


Assuntos
Quadruplex G , Neoplasias , Humanos , Regiões Promotoras Genéticas , Oncogenes , Receptores ErbB/genética
17.
Int Immunopharmacol ; 122: 110629, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37451020

RESUMO

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a head and neck malignant tumor with a high incidence and recurrence rate. The crosstalk between ferroptosis and tumor-associated macrophages (TAMs) is thought to have major implications in interfering with cancers. We intended to explore the effect of acyl-CoA synthetase long-chain family member 4 (ACSL4) on the pathogenesis of NPC via ferroptosis and TAMs. METHODS: Differential genes in NPC patients were analyzed using publicly available databases, and the ferroptosis-related gene ACSL4 was identified. Expression of ACSL4 in NPC cell lines and xenografted mice was examined. Colony formation, cell proliferation, migration, and invasion were assessed. The abundance of epithelial-mesenchymal transition (EMT) markers (E-cadherin, N-cadherin, and Vimentin) was confirmed. Lipid peroxidation levels and related markers were measured. Clophosome was administered to determine the role of TAMs in NPC mice. RESULTS: Low levels of ACSL4 were observed in NPC patients and CNE-2 and 5-8F cells. Erastin (a ferroptosis inducer) and ACSL4 increased lipid peroxidation, decreased cell viability, colony formation, cell proliferation, migration and invasion, and inhibited EMT. Moreover, Erastin and ACSL4 promoted M2 to M1 macrophage polarization. The effects of erastin and ACSL4 were additive. Ferrostatin-1, an inhibitor of ferroptosis, exerted the opposite effect and reversed the beneficial effects of ACSL4 overexpression. In xenograft mice, ACSL4 and clophosome hindered the growth of NPC, and extra clophosome slightly enhanced the antitumor effect of ACSL4. CONCLUSION: Our findings indicated that ACSL4 inhibited the pathogenesis of NPC, at least through crosstalk between ferroptosis and macrophages, providing potential direction for NPC therapy.


Assuntos
Ferroptose , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Animais , Humanos , Camundongos , Carcinogênese , Linhagem Celular Tumoral , Macrófagos/patologia , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/genética
18.
Front Microbiol ; 14: 1197981, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37485506

RESUMO

Objective: Host genetics and environment participate in the shaping of gut microbiota. Diannan small ear pigs and Diqing Tibetan pigs are excellent native pig breeds in China and live in different environments. However, the gut microbiota of Diannan small ear pigs and Diqing Tibetan pigs were still rarely understood. Therefore, this study aimed to analyze the composition characteristics of gut microbiota and metabolites in Diannan small ear pigs and Diqing Tibetan pigs. Methods: Fresh feces of 6 pigs were randomly collected from 20 4-month-old Diannan small ear pigs (DA group) and 20 4-month-old Diqing Tibetan pigs (TA group) for high-throughput 16S rRNA sequencing and liquid chromatography-mass spectrometry (LC-MS) non-targeted metabolome analysis. Results: The results revealed that Firmicutes and Bacteroidetes were the dominant phyla in the two groups. Chao1 and ACE indices differed substantially between DA and TA groups. Compared with the DA group, the relative abundance of Prevotellaceae, and Ruminococcus was significantly enriched in the TA group, while the relative abundance of Lachnospiraceae, Actinomyces, and Butyricicoccus was significantly reduced. Cholecalciferol, 5-dehydroepisterol, stigmasterol, adrenic acid, and docosahexaenoic acid were significantly enriched in DA group, which was involved in the steroid biosynthesis and biosynthesis of unsaturated fatty acids. 3-phenylpropanoic acid, L-tyrosine, phedrine, rhizoctin B, and rhizoctin D were significantly enriched in TA group, which was involved in the phenylalanine metabolism and phosphonate and phosphinate metabolism. Conclusion: We found that significant differences in gut microbiota composition and metabolite between Diannan small ear pigs and Diqing Tibetan pigs, which provide a theoretical basis for exploring the relationship between gut microbiota and pig breeds.

19.
iScience ; 26(6): 106947, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37324530

RESUMO

Phages widely exist in numerous environments from wastewater to deep ocean, representing a huge virus diversity, yet remain poorly characterized. Among them, jumbo phages are of particular interests due to their large genome (>200 kb) and unusual biology. To date, only six strains of jumbo phages infecting Klebsiella pneumoniae have been described. Here, we report the isolation and characterization of two jumbo phages from hospital wastewater representing the sixth genus: φKp5130 and φKp9438. Both phages showed lytic activity against broad range of clinical antibiotic-resistant K. pneumoniae strains and distinct physiology including long latent period, small burst size, and high resistance to thermal and pH stress. The treatment of sewage water with the phages cocktail resulted in dramatic decline in K. pneumoniae population. Overall, this study provides detailed molecular and genomics characterization of two novel jumbo phages, expands viral diversity, and provides novel candidate phages to facilitate environmental wastewater treatment.

20.
Cancer Sci ; 114(8): 3446-3460, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37271497

RESUMO

Acute myeloid leukemia (AML) is a major leukemia with high mortality. Ferroptosis is an important regulator of cancers. However, the role of ferroptosis and its regulatory mechanisms in AML remain largely unknown. In this study, we reported elevated brain and muscle ARNT-Like protein-1 (Bmal1) expression in AML patients and cell lines, and its upregulation indicated the poor survival of patients. The correlation analysis showed that Bmal1 expression was closely correlated with cytogenetics and the French-American-British subtypes, but was not correlated with age, gender and white blood cells. RSL3 reduced Bmal1 expression in HL-60 and NB4 cells. Malondialdehyde, total iron, Fe2+ , glutathione and lipid peroxidation were examined to evaluate ferroptosis. Overexpression of Bmal1 repressed RSL3-induced ferroptosis in AML cells. Bmal1 recruited Enhancer of zeste homolog 2 (EZH2) to the Early B cell factor 3 (EBF3) promoter and enhanced its methylation, thus suppressing EBF3 expression. Moreover, the knockdown of Bmal1 sensitized AML cells to RSL3-induced ferroptosis, and it was counteracted by EBF3 knockdown. Furthermore, EBF3 bound to the Arachidonate 15-pipoxygenase (ALOX15) promoter to enhance its expression, and overexpression of EBF3 enhanced RSL3-induced ferroptosis dependent on ALOX5. We established a subcutaneous AML xenograft tumor model and reported that knockdown of Bmal1 and overexpression of EBF3 restrained AML growth by promoting ALOX15-mediated ferroptosis in vivo. Collectively, Bmal1 inhibits RSL3-induced ferroptosis by promoting EZH2-mediated EBF3 methylation and suppressing the expression of EBF3 and ALOX15, thus accelerating AML.


Assuntos
Relógios Circadianos , Ferroptose , Leucemia Mieloide Aguda , Humanos , Linhagem Celular Tumoral , Células HL-60 , Leucemia Mieloide Aguda/metabolismo , Araquidonato 15-Lipoxigenase , Fatores de Transcrição
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