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1.
Bioresour Bioprocess ; 11(1): 43, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38664309

RESUMO

L-Threonine is an important feed additive with the third largest market size among the amino acids produced by microbial fermentation. The GRAS (generally regarded as safe) industrial workhorse Corynebacterium glutamicum is an attractive chassis for L-threonine production. However, the present L-threonine production in C. glutamicum cannot meet the requirement of industrialization due to the relatively low production level of L-threonine and the accumulation of large amounts of by-products (such as L-lysine, L-isoleucine, and glycine). Herein, to enhance the L-threonine biosynthesis in C. glutamicum, releasing the aspartate kinase (LysC) and homoserine dehydrogenase (Hom) from feedback inhibition by L-lysine and L-threonine, respectively, and overexpressing four flux-control genes were performed. Next, to reduce the formation of by-products L-lysine and L-isoleucine without the cause of an auxotrophic phenotype, the feedback regulation of dihydrodipicolinate synthase (DapA) and threonine dehydratase (IlvA) was strengthened by replacing the native enzymes with heterologous analogues with more sensitive feedback inhibition by L-lysine and L-isoleucine, respectively. The resulting strain maintained the capability of synthesizing enough amounts of L-lysine and L-isoleucine for cell biomass formation but exhibited almost no extracellular accumulation of these two amino acids. To further enhance L-threonine production and reduce the by-product glycine, L-threonine exporter and homoserine kinase were overexpressed. Finally, the rationally engineered non-auxotrophic strain ZcglT9 produced 67.63 g/L (17.2% higher) L-threonine with a productivity of 1.20 g/L/h (108.0% higher) in fed-batch fermentation, along with significantly reduced by-product accumulation, representing the record for L-threonine production in C. glutamicum. In this study, we developed a strategy of reconstructing the feedback regulation of amino acid metabolism and successfully applied this strategy to de novo construct a non-auxotrophic L-threonine producing C. glutamicum. The main end by-products including L-lysine, L-isoleucine, and glycine were almost eliminated in fed-batch fermentation of the engineered C. glutamicum strain. This strategy can also be used for engineering producing strains for other amino acids and derivatives.

2.
J Transl Med ; 22(1): 371, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637802

RESUMO

Platelets not only participate in thrombosis and hemostasis but also interact with tumor cells and protect them from mechanical damage caused by hemodynamic shear stress and natural killer cell lysis, thereby promoting their colonization and metastasis to distant organs. Platelets can affect the tumor microenvironment via interactions between platelet-related factors and tumor cells. Metastasis is a key event in cancer-related death and is associated with platelet-related factors in lung, breast, and colorectal cancers. Although the factors that promote platelet expression vary slightly in terms of their type and mode of action, they all contribute to the overall process. Recognizing the correlation and mechanisms between these factors is crucial for studying the colonization of distant target organs and developing targeted therapies for these three types of tumors. This paper reviews studies on major platelet-related factors closely associated with metastasis in lung, breast, and colorectal cancers.


Assuntos
Neoplasias Colorretais , Trombose , Humanos , Plaquetas/metabolismo , Hemostasia , Trombose/patologia , Neoplasias Colorretais/patologia , Metástase Neoplásica , Microambiente Tumoral
3.
BMJ Open ; 14(4): e074493, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38631826

RESUMO

INTRODUCTION: Pre-eclampsia (PE) affects about 5% of Chinese pregnant women and is a major cause of maternal and perinatal morbidity and mortality. The first trimester screening model developed by the Fetal Medicine Foundation, which uses the Bayes theorem to combine maternal characteristics and medical history together with measurements of biomarkers, has been proven to be effective and has superior screening performance to that of the traditional risk factor-based approach for the prediction of PE. Prophylactic use of low-dose aspirin in women at risk for PE has resulted in a lower incidence of preterm-PE. However, there is no consensus on the preferred aspirin dosage for the prevention of preterm-PE. Evidence has also suggested that metformin has the potential benefit in preventing PE in pregnant women who are at high risk of the disorder. METHOD AND ANALYSIS: We present a protocol (V.2.0, date 17 March 2022) for the AVERT trial, which is a multicentre, double-blinded, 3-arm randomised controlled trial (RCT) that uses an effective PE screening programme to explore the optimal dosage of aspirin and the role of metformin for the prevention of PE among high-risk pregnant women in China. We intend to recruit 66 000 singleton pregnancies without treatment of low-dose aspirin and metformin at 11-13 weeks' gestation and all eligible women attending for their first trimester routine scan will be invited to undergo screening for preterm-PE by the combination of maternal factors, mean arterial pressure and placental growth factor. Women found to be at high risk of developing preterm-PE will be invited to take part in the RCT. This study will compare the incidence of preterm-PE with delivery at <37 weeks' gestation, as the primary outcome, of three different interventional groups: (1) aspirin 75 mg daily, (2) aspirin 150 mg daily and (3) aspirin 75 mg with metformin 1.5 g daily. 957 participants per treatment group are required to detect a significant difference of 59% in the reduction of the incidence of preterm-PE with 80% power and type I error of 5%. Pregnancy and neonatal outcomes will be collected and analysed. ETHICS AND DISSEMINATION: Ethical approval for the study was obtained from the Joint Chinese University of Hong Kong-New Territories East Cluster Clinical Research Ethics Committee (CREC Ref. No. 2021.406) in Hong Kong and the Ethics Committee of each participating hospital in Mainland China. The study is registered at ClinicalTrials.gov. The results of the AVERT trial will be disseminated at international academic conferences and published in high-impact factor journals. TRIAL REGISTRATION NUMBER: NCT05580523.


Assuntos
Metformina , Pré-Eclâmpsia , Gravidez , Feminino , Recém-Nascido , Humanos , Aspirina , Pré-Eclâmpsia/epidemiologia , Método Duplo-Cego , China , Biomarcadores , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
4.
BMC Complement Med Ther ; 24(1): 168, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649990

RESUMO

OBJECTIVE: Many acupuncture acupoints are located on the posterior midline of the neck region. The needling depth for acupuncture is important for practitioners, and an unsafe needling depth increases the possibility of damage to the spinal cord and brainstem. Can the safety of acupuncture be assessed by examining bone structures? We focused on this aim to carry out this study. METHODS: The shortest distance from the posterior border of the foramen magnum to the line joining both upper ends of the posterior border of the mastoid process was measured on 29 skulls. Distances from the posterior border of the vertebral foramen to the tip of the spinous process and posterior tubercle of the atlas were measured and evaluated from 197 dry cervical vertebrae and 31 lateral cervical radiographs of patient subjects. The anatomic relationships of the vertebral canal with the external occipital protuberance, tip of the spinous process of the axis, tip of the posterior tubercle of the atlas, and upper end of the posterior border of the mastoid process were observed and evaluated via lateral cervical radiography. RESULTS: The shortest distance from the foramen magnum to the line between the mastoid processes was 4.65±1.75 mm, and the distance from the superior border of the vertebral foramen of the atlas to the posterior tubercle was less than the distance from the inferior border. The distance from the superior border of the vertebral canal to the tip of the spinous process in C2-C7 was greater than the distance from the inferior border. The mean lengths of the superior border of the C2 spinous process and the inferior border of the C7 spinous process were greater than 21 mm and 31 mm, respectively. The line from the upper end of the posterior border of the mastoid process to the tip of the C2 spinous process or 10 mm deep to the tip of the C2 spinous process was posterior to the vertebral canal. CONCLUSIONS: On the posterior midline of the neck region between the tip of spinous process of axis and external occipital protuberance, if the needle reaches the depth of the line between the upper end of posterior border of mastoid process and the tip of the spinous process of the axis, approximately 10 mm along the spinous process of the axis, the needle is in the safe region. The mean length of the C2-C7 spinous process is suitable to accommodate the needling depth of the adjacent acupoint. Bone structures can be used to effectively assess the safety of acupuncture on the posterior midline of the neck region.

5.
Toxics ; 12(4)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38668505

RESUMO

Lead (Pb) and arsenic (As) are commonly occurring heavy metals in the environment and produce detrimental impacts on the central nervous system. Although they have both been indicated to exhibit neurotoxic properties, it is not known if they have joint effects, and their mechanisms of action are likewise unknown. In this study, zebrafish were exposed to different concentrations of Pb (40 µg/L, 4 mg/L), As (32 µg/L, 3.2 mg/L) and their combinations (40 µg/L + 32 µg/L, 4 mg/L + 3.2 mg/L) for 30 days. The histopathological analyses showed significant brain damage characterized by glial scar formation and ventricular enlargement in all exposed groups. In addition, either Pb or As staining inhibited the swimming speed of zebrafish, which was enhanced by their high concentrations in a mixture. To elucidate the underlying mechanisms, we examined changes in acetylcholinesterase (AChE) activity, neurotransmitter (dopamine, 5-hydroxytryptamine) levels, HPI axis-related hormone (cortisol and epinephrine) contents and neurodevelopment-related gene expression in zebrafish brain. The observations suggest that combined exposure to Pb and As can cause abnormalities in swimming behavior and ultimately exacerbate neurotoxicity in zebrafish by interfering with the cholinergic system, dopamine and 5-hydroxytryptamine signaling, HPI axis function as well as neuronal development. This study provides an important theoretical basis for the mixed exposure of heavy metals and their toxicity to aquatic organisms.

6.
Huan Jing Ke Xue ; 45(5): 2848-2858, 2024 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-38629547

RESUMO

The application of biomarkers to study the molecular composition of soil organic matter (SOM) can be used to analyze the source and degradation of SOM and reveal the stability mechanism of soil organic carbon (SOC) at the molecular level. In order to further clarify the effects of different land use patterns (farmland, grassland, and forest) on the molecular composition of SOM, the changes in molecular composition of organic matter (free lipids, cutin, suberin, and lignin) on a global scale were studied using a meta-analysis method. The results showed that there were significant differences in the molecular composition of organic matter under different land use patterns. The contents of free lipids (n-alkanes, n-alkanols, n-alkanoic acids, and cyclic lipids), cutin, and lignin phenols in forest soil were significantly higher than those in grassland and farmland. There was no significant difference in the content of suberin between grassland and forest soil. The ratio of suberin to cutin in grassland was the highest, with an average of 2.96, and the averages of farmland and forest were 1.68 and 2.21, respectively. The ratio of syringic acid to syringaldehyde (Ad/Al)S and the ratio of vanillic acid to vanillin (Ad/Al)V of farmland soil were the largest, which were 1.25 and 1.58, respectively, and were significantly higher than those in grassland (0.46 and 0.69) and forest (0.78 and 0.7). The results of correlation analysis showed that in farmland soil, suberin was significantly correlated with mean annual precipitation (MAP) and clay; cutin was significantly correlated with clay; and lignin was significantly correlated with mean annual temperature (MAT), MAP, sand, and bulk density. In grassland soil, total free lipids were significantly correlated with MAP and bulk density; suberin and cutin were significantly correlated with MAT and MAP; and lignin was significantly correlated with MAP, pH, sand, and bulk density. However, only lignin was significantly correlated with MAP and sand in forest soils. Overall, the contents of SOC and molecular components in forest soil were higher under the three land use practices, and the contribution of plant roots to SOM in grassland soil was greater. In farmland soil, the degradation of lignin was accelerated due to human farming activities. Future research should focus on the regulation of soil physicochemical properties and climatic conditions on the molecular composition of SOM.

7.
New Phytol ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38571393

RESUMO

The conquest of land by plants was concomitant with, and possibly enabled by, the evolution of three-dimensional (3D) growth. The moss Physcomitrium patens provides a model system for elucidating molecular mechanisms in the initiation of 3D growth. Here, we investigate whether the phytohormone ethylene, which is believed to have been a signal before land plant emergence, plays a role in 3D growth regulation in P. patens. We report ethylene controls 3D gametophore formation, based on results from exogenously applied ethylene and genetic manipulation of PpEIN2, which is a central component in the ethylene signaling pathway. Overexpression (OE) of PpEIN2 activates ethylene responses and leads to earlier formation of gametophores with fewer gametophores produced thereafter, phenocopying ethylene-treated wild-type. Conversely, Ppein2 knockout mutants, which are ethylene insensitive, show initially delayed gametophore formation with more gametophores produced later. Furthermore, pharmacological and biochemical analyses reveal auxin levels are decreased in the OE lines but increased in the knockout mutants. Our results suggest that evolutionarily, ethylene and auxin molecular networks were recruited to build the plant body plan in ancestral land plants. This might have played a role in enabling ancient plants to acclimate to the continental surfaces of the planet.

8.
Chem Biodivers ; : e202400519, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38576052

RESUMO

One new highly degraded steroid, namely 21-nor-4-ene-chaxine A (1) furnishing a 5/6/5-tricyclic, along with one known related analogue (2), were isolated from the South China Sea sponge Spongia officinalis. Their structures including absolute configurations were established by extensive spectroscopic data analysis, TDDFT-ECD calculation, and comparison with the spectral data previously reported in the literature. Compound 1 represent the new member of incisterols family with a highly degradation in ring B. In vitro bioassays revealed compound 2 exhibited significant anti-microglial inflammatory effect on lipopolysaccharide (LPS)-induced inflammation in BV-2 microglial cells.

10.
ISA Trans ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38631933

RESUMO

This paper investigates the problem of bumpless transfer control for switched impulsive positive systems with L1-gain performance. For switched impulsive positive systems, the control bump is brought from both switching behavior and impulsive effects. First, the concept of bumpless transfer performance is proposed by imposing magnitude constraints on the control signal to measure the level of bumpless transfer in the switched impulsive positive system. Then, based on a new class of multiple piecewise-continuous copositive Lyapunov function, a tighter mode-dependent average dwell time switching signal bound and bumpless transfer controller are designed to realize positive property, bumpless transfer and L1-gain performance of the closed-loop systems. Finally, the feasibility and superiority of the proposed control strategy are illustrated by simulations.

11.
Cardiology ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615672

RESUMO

INTRODUCTION: Calcium channel gene variations have been reported to be associated with hypertrophic cardiomyopathy (HCM) in family, but the relationship between calcium channel gene variations and HCM remains undefined in population. METHODS: A total of 719 HCM unrelated patients were initially enrolled. Finally, 371 patients were identified based on inclusion and exclusion criteria, including 145 patients with gene negative, 28 patients with a single rare calcium channel gene variation (calcium gene variation), 162 patients with a single pathogenic/likely pathogenic sarcomere gene variation (sarcomere gene variation) and 36 patients with a single pathogenic/likely pathogenic sarcomere gene variation and a single rare calcium channel gene variation (double gene variations). Then the demographic, electrocardiographic, echocardiographic and follow-up data were collected. RESULTS: Patients with double gene variations were at an earlier age and had more percent of family history of HCM, and had thicker walls, higher left ventricular outflow tract pressure gradient, more pathological Q waves, and more bundle branch block as compared with those with single sarcomere gene variation. During the follow-up period, patients with double gene variations had more primary endpoints than other three groups (p=0.0013). Multivariate analysis showed that double gene variations was the independent predictor of for primary endpoint events in patients (HR 4.82, 95% CI 1.77 to 13.2; p=0.002). CONCLUSION: We found that patients with double gene variations had more severe HCM phenotype and prognosis. The pathogenesis effects of sarcomere gene variation and calcium channel gene variation may be cumulative in HCM populations.

12.
Opt Express ; 32(5): 7342-7355, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38439417

RESUMO

Coherent superposition has been proposed to synthesize high-order quadrature amplitude modulation (QAM) by coherently superposing low-order QAMs in the optical domain. These approaches could effectively relax the digital-to-analog converter resolution and reduce the complexity of the driving electronics. However, in the superposition process, imperfect phase rotations (IPRs) in low-order QAMs will be transferred to the resultant high-order QAM. Importantly, the induced IPR cannot be compensated for by conventional linear equalizers and carrier recovery methods. To combat the induced IPR, herein, we propose a hierarchical blind phase search (HBPS) algorithm to compensate for the IPRs in synthesized high-order QAMs. The proposed HBPS can match the generation mechanism of the IPRs in coherent superposition, by tracing back and estimating the IPR in the QPSK-like constellation of each hierarchy and finally correcting the induced IPRs. Simulation and experimental results verify that this algorithm could effectively compensate for the IPR in the resultant 16-QAMs synthesized using coherent superposition approaches. The proposed HBPS shows significant optical signal-to-noise ratio (OSNR) gains compared to the conventional blind phase search (BPS) method for high-order QAMs coherently superposed using optical signal processing (OSP) and tandem modulators (TMs). Specifically, at the BER of 2.4e-2, the HBPS achieves a 1.5-dB OSNR sensitivity enhancement over the BPS in either OSP or TMs-based schemes, even with an imperfection rotation of up to 20∘.

13.
Environ Toxicol ; 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38440848

RESUMO

BACKGROUND: Sepsis remains a crucial global health issue characterized by high mortality rates and a lack of specific treatments. This study aimed to elucidate the molecular mechanisms underlying sepsis and to identify potential therapeutic targets and compounds. METHODS: High-throughput sequencing data from the GEO database (GSE26440 as the training set and GSE13904 and GSE32707 as the validation sets), weighted gene co-expression network analysis (WGCNA), Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, alongside a combination of PPI and machine learning methods (LASSO and SVM) were utilized. RESULTS: WGCNA identified the black module as positively correlated, and the green module as negatively correlated with sepsis. Further intersections of these module genes with age-related genes yielded 57 sepsis-related genes. GO and KEGG pathway enrichment analysis, PPI, LASSO, and SVM selected six hub aging-related genes: BCL6, FOS, ETS1, ETS2, MAPK14, and MYC. A diagnostic model was constructed based on these six core genes, presenting commendable performance in both the training and validation sets. Notably, ETS1 demonstrated significant differential expression between mild and severe sepsis, indicating its potential as a biomarker of severity. Furthermore, immune infiltration analysis of these six core genes revealed their correlation with most immune cells and immune-related pathways. Additionally, compounds were identified in the traditional Chinese medicine Danshen, which upon further analysis, revealed 354 potential target proteins. GO and KEGG enrichment analysis of these targets indicated a primary enrichment in inflammation and immune-related pathways. A Venn diagram intersects these target proteins, and our aforementioned six core genes yielded three common genes, suggesting the potential efficacy of Danshen in sepsis treatment through these genes. CONCLUSIONS: This study highlights the pivotal roles of age-related genes in the molecular mechanisms of sepsis, offers potential biomarkers, and identifies promising therapeutic compounds, laying a robust foundation for future studies on the treatment of sepsis.

14.
Nat Commun ; 15(1): 1950, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431640

RESUMO

In muscular dystrophies, muscle fibers loose integrity and die, causing significant suffering and premature death. Strikingly, the extraocular muscles (EOMs) are spared, functioning well despite the disease progression. Although EOMs have been shown to differ from body musculature, the mechanisms underlying this inherent resistance to muscle dystrophies remain unknown. Here, we demonstrate important differences in gene expression as a response to muscle dystrophies between the EOMs and trunk muscles in zebrafish via transcriptomic profiling. We show that the LIM-protein Fhl2 is increased in response to the knockout of desmin, plectin and obscurin, cytoskeletal proteins whose knockout causes different muscle dystrophies, and contributes to disease protection of the EOMs. Moreover, we show that ectopic expression of fhl2b can partially rescue the muscle phenotype in the zebrafish Duchenne muscular dystrophy model sapje, significantly improving their survival. Therefore, Fhl2 is a protective agent and a candidate target gene for therapy of muscular dystrophies.


Assuntos
Proteínas com Domínio LIM , Proteínas Musculares , Distrofia Muscular de Duchenne , Músculos Oculomotores , Animais , Proteínas do Citoesqueleto/metabolismo , Distrofina/genética , Expressão Ectópica do Gene , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/metabolismo , Músculos Oculomotores/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas Musculares/metabolismo , Proteínas com Domínio LIM/metabolismo
15.
Cancers (Basel) ; 16(5)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38473416

RESUMO

BACKGROUND: An atypical teratoid/rhabdoid tumor (AT/RT) is an uncommon and aggressive pediatric central nervous system neoplasm. However, a universal clinical consensus or reliable prognostic evaluation system for this malignancy is lacking. Our study aimed to develop a risk model based on comprehensive clinical data to assist in clinical decision-making. METHODS: We conducted a retrospective study by examining data from the Surveillance, Epidemiology, and End Results (SEER) repository, spanning 2000 to 2019. The external validation cohort was sourced from the Children's Hospital Affiliated to Chongqing Medical University, China. To discern independent factors affecting overall survival (OS) and cancer-specific survival (CSS), we applied Least Absolute Shrinkage and Selection Operator (LASSO) and Random Forest (RF) regression analyses. Based on these factors, we structured nomogram survival predictions and initiated a dynamic online risk-evaluation system. To contrast survival outcomes among diverse treatments, we used propensity score matching (PSM) methodology. Molecular data with the most common mutations in AT/RT were extracted from the Catalogue of Somatic Mutations in Cancer (COSMIC) database. RESULTS: The annual incidence of AT/RT showed an increasing trend (APC, 2.86%; 95% CI:0.75-5.01). Our prognostic study included 316 SEER database participants and 27 external validation patients. The entire group had a median OS of 18 months (range 11.5 to 24 months) and median CSS of 21 months (range 11.7 to 29.2). Evaluations involving C-statistics, DCA, and ROC analysis underscored the distinctive capabilities of our prediction model. An analysis via PSM highlighted that individuals undergoing triple therapy (integrating surgery, radiotherapy, and chemotherapy) had discernibly enhanced OS and CSS. The most common mutations of AT/RT identified in the COSMIC database were SMARCB1, BRAF, SMARCA4, NF2, and NRAS. CONCLUSIONS: In this study, we devised a predictive model that effectively gauges the prognosis of AT/RT and briefly analyzed its genomic features, which might offer a valuable tool to address existing clinical challenges.

16.
Vet Microbiol ; 292: 110066, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38555788

RESUMO

Porcine reproductive and respiratory syndrome (PRRS), which has posed substantial threats to the swine industry worldwide, is primarily characterized by interstitial pneumonia. A disintegrin and metalloproteinase 17 (ADAM17) is a multifunctional sheddase involved in various inflammatory diseases. Herein, our study showed that PRRS virus (PRRSV) infection elevated ADAM17 activity, as demonstrated in primary porcine alveolar macrophages (PAMs), an immortalized PAM cell line (IPAM cells), and the lung tissues of PRRSV-infected piglets. We found that PRRSV infection promoted ADAM17 translocation from the endoplasmic reticulum to the Golgi by enhancing its interaction with inactive rhomboid protein 2 (iRhom2), a newly identified ADAM17 regulator, which in turn elevated ADAM17 activity. By screening for PRRSV-encoded structural proteins, viral envelope (E) and nucleocapsid (N) proteins were identified as the predominant ADAM17 activators. E and N proteins bind with both ADAM17 and iRhom2 to form ternary protein complexes, ultimately strengthening their interactions. Additionally, we demonstrated, using an ADAM17-knockout cell line, that ADAM17 augmented the shedding of soluble TNF-α, a pivotal inflammatory mediator. We also discovered that ADAM17-mediated cleavage of porcine TNF-α occurred between Arg-78 and Ser-79. By constructing a precision mutant cell line with Arg-78-Glu/Ser-79-Glu substitution mutations in TNF-α, we further revealed that the ADAM17-mediated production of soluble TNF-α contributed to the induction of inflammatory responses by PRRSV and its E and N proteins. Taken together, our results elucidate the mechanism by which PRRSV infection activates the iRhom2/ADAM17/TNF-α axis to enhance inflammatory responses, providing valuable insights into the elucidation of PRRSV pathogenesis.


Assuntos
Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Doenças dos Suínos , Suínos , Animais , Síndrome Respiratória e Reprodutiva Suína/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Pulmão , Macrófagos Alveolares
17.
Trends Immunol ; 45(4): 274-287, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38494365

RESUMO

Lipopolysaccharide (LPS), a key component of the outer membrane in Gram-negative bacteria (GNB), is widely recognized for its crucial role in mammalian innate immunity and its link to mortality in intensive care units. While its recognition via the Toll-like receptor (TLR)-4 receptor on cell membranes is well established, the activation of the cytosolic receptor caspase-11 by LPS is now known to lead to inflammasome activation and subsequent induction of pyroptosis. Nevertheless, a fundamental question persists regarding the mechanism by which LPS enters host cells. Recent investigations have identified at least four primary pathways that can facilitate this process: bacterial outer membrane vesicles (OMVs); the spike (S) protein of SARS-CoV-2; host-secreted proteins; and host extracellular vesicles (EVs). These delivery systems provide new avenues for therapeutic interventions against sepsis and infectious diseases.


Assuntos
Imunidade Inata , Lipopolissacarídeos , Animais , Humanos , Inflamassomos/metabolismo , Caspases/metabolismo , Mamíferos
18.
J Dermatol Sci ; 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38556434

RESUMO

BACKGROUND: Treg plays a pivotal role in the suppression of Th2 cell and the maintenance of immune homeostasis. The precise molecular mechanism underlying the disruption of Treg suppression of Th2 cell and the promotion of Th2 type inflammation in allergic diseases remains elusive. OBJECTIVE: This study aims to investigate the molecular mechanism underlying quantitative and functional changes of Treg in AD. METHODS: The molecular mechanism was investigated using flow cytometry, mRNA sequencing, co-culture experiments, co-immunoprecipitation, chromatin immunoprecipitation, and bisulfite sequencing in vitro or in AD mice model and patients with AD. RESULTS: Increased proportion of Treg was detected in mild and moderate AD. Conversely, characteristic decrease in both the number and CTLA-4 expression of Treg was relevant to serum IL-4 level in severe AD patients, which was verified under a high concentration of IL-4 treatment in vitro. The underlying mechanism is that IL-4/pSTAT6 pathway recruits DNMT1 and HDAC2 to inhibit transcriptional regulation of Foxp3 and CTLA-4 loci. High level of IL-4 impaired the suppression of Treg against Th2 cell differentiation mediated by CTLA-4, and blockade of IL-4Rα signaling in Treg restored Treg number and suppression of Th2 cell in AD model mice and patients with AD. CONCLUSION: The number of Treg is relevant to stratification of severity and serum IL-4 level in patients with AD. Abnormal high level of IL-4 epigenetically triggers a decrease in both the number and CTLA-4 expression of Treg. The reduced expression of CTLA-4 on Treg induced by IL-4 impairs suppression of Th2 cell differentiation.

19.
Redox Biol ; 71: 103112, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38461791

RESUMO

The Warburg effect, also referred as aerobic glycolysis, is a common metabolic program during viral infection. Through targeted metabolomics combined with biochemical experiments and various cell models, we investigated the central carbon metabolism (CCM) profiles of cells infected with porcine deltacoronavirus (PDCoV), an emerging enteropathogenic coronavirus with zoonotic potential. We found that PDCoV infection required glycolysis but decreased glycolytic flux, exhibiting a non-Warburg effect characterized by pyruvic acid accumulation. Mechanistically, PDCoV enhanced pyruvate kinase activity to promote pyruvic acid anabolism, a process that generates pyruvic acid with concomitant ATP production. PDCoV also hijacked pyruvic acid catabolism to increase biosynthesis of non-essential amino acids (NEAAs), suggesting that pyruvic acid is an essential hub for PDCoV to scavenge host energy and metabolites. Furthermore, PDCoV facilitated glutaminolysis to promote the synthesis of NEAA and pyrimidines for optimal proliferation. Our work supports a novel CCM model after viral infection and provides potential anti-PDCoV drug targets.


Assuntos
Infecções por Coronavirus , Coronavirus , Doenças dos Suínos , Suínos , Animais , Coronavirus/metabolismo , Ácido Pirúvico/metabolismo , Doenças dos Suínos/metabolismo , Doenças dos Suínos/patologia , Infecções por Coronavirus/patologia
20.
Radiother Oncol ; 195: 110259, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38548112

RESUMO

BACKGROUND AND AIMS: Radiotherapy is widely applied for lung adenocarcinoma (LUAD), while individualized differences led to different outcomes. This study aimed to establish a multi-gene risk scoring model to predict the benefits of LUAD patients from radiotherapy, based on different types of cell death respectively. RESULTS: Other than autophagy, pyroptosis, ferroptosis and Immunogenic cell death (ICD), the LUAD prognostic model based on apoptosis had the best performance, and the area under curves (AUCs) of the receiver operating curve (ROC) for 1-, 3-, and 5-year OS were 0.700,0.736,0.723,respectively. Such genes were involved as SLC7A5, EXO1, ABAT, NLRP1 and GAR1. Then patients were divided into high and low risk groups by the median apoptosis-LUAD risk score. For patients in the high-risk group, i.e., the radiotherapy-tolerant group, we screened adjuvant chemotherapy and found that besides the conventional first-line chemotherapy regimen, drugs such as Fludarabine, Pevonedistat, and Podophyllotoxin Bromide may also have potential therapeutic value. CONCLUSION: The multi-gene risk scoring model based on apoptosis might predict the radiotherapy benefits of LUAD patients and for those radioresistant patients classified by the model we also provided effective adjuvant chemicals, which would be used to guide clinical treatment.

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