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2.
Sci Total Environ ; 946: 174257, 2024 Jun 25.
Article de Anglais | MEDLINE | ID: mdl-38936721

RÉSUMÉ

The influence of tree age on the growth response of Picea likiangensis, a predominant timber species in southwestern China, to climatic factors has been under-researched. In this study, we examined the relationships between tree age and the response of P. likiangensis to climatic factors and extreme drought events using tree-ring samples procured from the southeastern edge of the Tibetan Plateau. The results revealed differential responses of the radial growth of P. likiangensis trees of varying ages to climatic factors and extreme drought events. Specifically, deficient water availability during the early growing season emerged as the principal factor constraining radial growth across all age classes. Young and middle-aged trees (<100 years) demonstrated greater responsiveness to water availability than did mature trees (>100 years). Mature trees, in contrast, demonstrated markedly greater resistance to extreme drought events than young and middle-aged trees. Comparative studies of individual trees across different ages revealed negligible differences in the response of young and middle-aged trees to climatic factors and extreme drought events. Given these responses, future forest management practices should prioritize young and middle-aged trees that are more affected by drought to maximize the ecological value of the species. According to the specific research objectives, sample collection processes should classify mature trees and young and middle-aged trees, to minimize the influence of tree age on the final findings of the study.

3.
Plant Physiol Biochem ; 213: 108805, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38861819

RÉSUMÉ

Transcription factors play crucial roles in almost all physiological processes including leaf senescence. Cell death is a typical symptom appearing in senescing leaves, which is also classified as developmental programmed cell death (PCD). However, the link between PCD and leaf senescence still remains unclear. Here, we found a WRKY transcription factor WRKY47 positively modulates age-dependent leaf senescence in Arabidopsis (Arabidopsis thaliana). WRKY47 was expressed preferentially in senescing leaves. A subcellular localization assay indicated that WRKY47 was exclusively localized in nuclei. Overexpression of WRKY47 showed precocious leaf senescence, with less chlorophyll content and higher electrolyte leakage, but loss-of-function mutants of WRKY47 delayed this biological process. Through qRT-PCR and dual luciferase reporter assays, we found that WRKY47 could activate the expression of senescence-associated genes (SAGs) and PCD-associated genes to regulate leaf senescence. Furthermore, through electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP)-qPCR, WRKY47 was found to bind to W-box fragments in promoter regions of BFN1 (Bifunctional Nuclease 1) and MC6 (Metacaspase 6) directly. In general, our research revealed that WRKY47 regulates age-dependent leaf senescence by activating the transcription of two PCD-associated genes.


Sujet(s)
Protéines d'Arabidopsis , Arabidopsis , Régulation de l'expression des gènes végétaux , Feuilles de plante , Sénescence des plantes , Facteurs de transcription , Arabidopsis/génétique , Arabidopsis/métabolisme , Protéines d'Arabidopsis/génétique , Protéines d'Arabidopsis/métabolisme , Feuilles de plante/métabolisme , Feuilles de plante/génétique , Facteurs de transcription/métabolisme , Facteurs de transcription/génétique , Sénescence des plantes/génétique , Régions promotrices (génétique)/génétique , Apoptose/génétique
4.
Physiol Plant ; 176(3): e14371, 2024.
Article de Anglais | MEDLINE | ID: mdl-38837414

RÉSUMÉ

The WRKY transcription factor (TF) genes form a large family in higher plants, with 72 members in Arabidopsis (Arabidopsis thaliana). The gaseous phytohormone ethylene (ET) regulates multiple physiological processes in plants. It is known that 1-aminocyclopropane-1-carboxylic acid (ACC) synthases (ACSs, EC 4.4.1.14) limit the enzymatic reaction rate of ethylene synthesis. However, whether WRKY TFs regulate the expression of ACSs and/or ACC oxidases (ACOs, EC 1.14.17.4) remains largely elusive. Here, we demonstrated that Arabidopsis WRKY22 positively regulated the expression of a few ACS and ACO genes, thus promoting ethylene production. Inducible overexpression of WRKY22 caused shorter hypocotyls without ACC treatment. A qRT-PCR screening demonstrated that overexpression of WRKY22 activates the expression of several ACS and ACO genes. The promoter regions of ACS5, ACS11, and ACO5 were also activated by WRKY22, which was revealed by a dual luciferase reporter assay. A follow-up chromatin immunoprecipitation coupled with quantitative PCR (ChIP-qPCR) and electrophoretic mobility shift assay (EMSA) showed that the promoter regions of ACS5 and ACO5 could be bound by WRKY22 directly. Moreover, wrky22 mutants had longer primary roots and more lateral roots than wild type, while WRKY22-overexpressing lines showed the opposite phenotype. In conclusion, this study revealed that WRKY22 acts as a novel TF activating, at least, the expression of ACS5 and ACO5 to increase ethylene synthesis and modulate root development.


Sujet(s)
Protéines d'Arabidopsis , Arabidopsis , Éthylènes , Régulation de l'expression des gènes végétaux , Lyases , Racines de plante , Facteurs de transcription , Arabidopsis/génétique , Arabidopsis/croissance et développement , Arabidopsis/métabolisme , Éthylènes/métabolisme , Éthylènes/biosynthèse , Facteurs de transcription/métabolisme , Facteurs de transcription/génétique , Protéines d'Arabidopsis/génétique , Protéines d'Arabidopsis/métabolisme , Racines de plante/génétique , Racines de plante/croissance et développement , Racines de plante/métabolisme , Lyases/génétique , Lyases/métabolisme , Amino-acid oxidoreductases/génétique , Amino-acid oxidoreductases/métabolisme , Régions promotrices (génétique)/génétique , Carbon-carbon lyases/métabolisme , Carbon-carbon lyases/génétique , Activation de la transcription/génétique
5.
Ecol Lett ; 27(6): e14447, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38844351

RÉSUMÉ

Host specialization plays a critical role in the ecology and evolution of plant-microbe symbiosis. Theory predicts that host specialization is associated with microbial genome streamlining and is influenced by the abundance of host species, both of which can vary across latitudes, leading to a latitudinal gradient in host specificity. Here, we quantified the host specificity and composition of plant-bacteria symbioses on leaves across 329 tree species spanning a latitudinal gradient. Our analysis revealed a predominance of host-specialized leaf bacteria. The degree of host specificity was negatively correlated with bacterial genome size and the local abundance of host plants. Additionally, we found an increased host specificity at lower latitudes, aligning with the high prevalence of small bacterial genomes and rare host species in the tropics. These findings underscore the importance of genome streamlining and host abundance in the evolution of host specificity in plant-associated bacteria along the latitudinal gradient.


Sujet(s)
Taille du génome , Spécificité d'hôte , Feuilles de plante , Symbiose , Feuilles de plante/microbiologie , Bactéries/génétique , Bactéries/classification , Génome bactérien , Arbres/microbiologie
6.
Biochem Pharmacol ; : 116372, 2024 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-38885773

RÉSUMÉ

MicroRNA and mitofusin-2 (Mfn2) play an important role in the myocardial apoptosis induced by acute myocardial infarction (AMI). However, the target relationship and underlying mechanism associated with interorganelle interaction between endoplasmic reticulum (ER) and mitochondria under ischemic condition is not completely clear. MI-induced injury, Mfn2 expression, Mfn2-mediated mitochondrial function and ER stress, and target regulation by miRNA-15b (miR-15b) were evaluated by animal MI and cellular hypoxic models with advanced molecular techniques. The results confirmed that Mfn2 was down-regulated and miR-15b was up-regulated upon the target binding profile under ischemic/hypoxic condition. Our data showed that miR-15b caused cardiac apoptotic injury that was reversed by rAAV9-anti-miR-15b or AMO-15b. The damage effect of miR-15b on Mfn2 expression and mitochondrial function was observed and rescued by rAAV9-anti-miR-15b or AMO-15b. The targeted regulation of miR-15b on Mfn2 was verified by luciferase reporter and microRNA-masking. Importantly, miR-15b-mediated Mfn2 suppression activated PERK/CHOP pathway, by which leads to ER stress and mitochondrial dysfunction, and cardiac apoptosis eventually. In conclusion, our research, for the first time, revealed the missing molecular link in Mfn2 and apoptosis and elucidated that pro-apoptotic miR-15b plays crucial roles during the pathogenesis of AMI through down-regulation of Mfn2 and activation of PERK-mediated ER stress. These findings may provide an opportunity to develop new therapies for prophylaxis and treatment of ischemic heart disease.

7.
Front Endocrinol (Lausanne) ; 15: 1394785, 2024.
Article de Anglais | MEDLINE | ID: mdl-38883597

RÉSUMÉ

Osteoporosis (OP) is a chronic systemic bone metabolism disease characterized by decreased bone mass, microarchitectural deterioration, and fragility fractures. With the demographic change caused by long lifespans and population aging, OP is a growing health problem. The role of miRNA in the pathogenesis of OP has also attracted widespread attention from scholars in recent years. Type H vessels are unique microvessels of the bone and have become a new focus in the pathogenesis of OP because they play an essential role in osteogenesis-angiogenesis coupling. Previous studies found some miRNAs regulate type H vessel formation through the regulatory factors, including platelet-derived growth factor-BB (PDGF-BB), hypoxia-inducible factor 1α (HIF-1α), vascular endothelial growth factor (VEGF), and so on. These findings help us gain a more in-depth understanding of the relationship among miRNAs, type H vessels, and OP to find a new perspective on treating OP. In the present mini-review, we will introduce the role of type H vessels in the pathogenesis of OP and the regulation of miRNAs on type H vessel formation by affecting regulatory factors to provide some valuable insights for future studies of OP treatment.


Sujet(s)
microARN , Ostéoporose , Animaux , Humains , Os et tissu osseux/vascularisation , Os et tissu osseux/métabolisme , Os et tissu osseux/anatomopathologie , microARN/génétique , microARN/métabolisme , Microvaisseaux/anatomopathologie , Microvaisseaux/métabolisme , Néovascularisation pathologique/génétique , Néovascularisation pathologique/métabolisme , Néovascularisation pathologique/anatomopathologie , Ostéogenèse/génétique , Ostéogenèse/physiologie , Ostéoporose/génétique , Ostéoporose/métabolisme , Ostéoporose/anatomopathologie
8.
Mil Med Res ; 11(1): 36, 2024 Jun 11.
Article de Anglais | MEDLINE | ID: mdl-38863031

RÉSUMÉ

BACKGROUND: Dysregulation of enhancer transcription occurs in multiple cancers. Enhancer RNAs (eRNAs) are transcribed products from enhancers that play critical roles in transcriptional control. Characterizing the genetic basis of eRNA expression may elucidate the molecular mechanisms underlying cancers. METHODS: Initially, a comprehensive analysis of eRNA quantitative trait loci (eRNAQTLs) was performed in The Cancer Genome Atlas (TCGA), and functional features were characterized using multi-omics data. To establish the first eRNAQTL profiles for colorectal cancer (CRC) in China, epigenomic data were used to define active enhancers, which were subsequently integrated with transcription and genotyping data from 154 paired CRC samples. Finally, large-scale case-control studies (34,585 cases and 69,544 controls) were conducted along with multipronged experiments to investigate the potential mechanisms by which candidate eRNAQTLs affect CRC risk. RESULTS: A total of 300,112 eRNAQTLs were identified across 30 different cancer types, which exert their influence on eRNA transcription by modulating chromatin status, binding affinity to transcription factors and RNA-binding proteins. These eRNAQTLs were found to be significantly enriched in cancer risk loci, explaining a substantial proportion of cancer heritability. Additionally, tumor-specific eRNAQTLs exhibited high responsiveness to the development of cancer. Moreover, the target genes of these eRNAs were associated with dysregulated signaling pathways and immune cell infiltration in cancer, highlighting their potential as therapeutic targets. Furthermore, multiple ethnic population studies have confirmed that an eRNAQTL rs3094296-T variant decreases the risk of CRC in populations from China (OR = 0.91, 95%CI 0.88-0.95, P = 2.92 × 10-7) and Europe (OR = 0.92, 95%CI 0.88-0.95, P = 4.61 × 10-6). Mechanistically, rs3094296 had an allele-specific effect on the transcription of the eRNA ENSR00000155786, which functioned as a transcriptional activator promoting the expression of its target gene SENP7. These two genes synergistically suppressed tumor cell proliferation. Our curated list of variants, genes, and drugs has been made available in CancereRNAQTL ( http://canernaqtl.whu.edu.cn/#/ ) to serve as an informative resource for advancing this field. CONCLUSION: Our findings underscore the significance of eRNAQTLs in transcriptional regulation and disease heritability, pinpointing the potential of eRNA-based therapeutic strategies in cancers.


Sujet(s)
Éléments activateurs (génétique) , Tumeurs , Locus de caractère quantitatif , Humains , Éléments activateurs (génétique)/génétique , Tumeurs/génétique , Variation génétique/génétique , Étude d'association pangénomique/méthodes , Tumeurs colorectales/génétique , Études cas-témoins , ARN/génétique , Chine ,
9.
Biol Methods Protoc ; 9(1): bpae037, 2024.
Article de Anglais | MEDLINE | ID: mdl-38863526

RÉSUMÉ

Molecular techniques that recover unknown sequences next to a known sequence region have been widely applied in various molecular studies, such as chromosome walking, identification of the insertion site of transposon mutagenesis, fusion gene partner, and chromosomal breakpoints, as well as targeted sequencing library preparation. Although various techniques have been introduced for efficiency enhancement, searching for relevant single molecular event present in a large-sized genome remains challenging. Here, the optimized ligation-mediated polymerase chain reaction (PCR) method was developed and successfully identified chromosomal breakpoints far away from the exon of the new exon junction without the need for nested PCR. In addition to recovering unknown sequences next to a known sequence region, the high efficiency of the method could also improve the performance of targeted  next-generation sequencing (NGS).

10.
Patient Prefer Adherence ; 18: 1141-1150, 2024.
Article de Anglais | MEDLINE | ID: mdl-38863947

RÉSUMÉ

Objective: This study aimed to explore the needs and constraints to cardiac rehabilitation (CR) among patients diagnosed with coronary heart disease (CHD) in a community-based setting, and thereby facilitating the implementation of effective CR programs for this population. Methods: Focus group interviews were used as the primary research methodology. A total of 11 community-dwelling individuals diagnosed with CHD were selected from a community hospital to participate in in-depth interviews, aiming to discern and analyze their requirements and constraints experienced concerning medical resources and healthcare agency. The textual data underwent examination using Colaizzi's method of descriptive data analysis. Results: Deficits existed in the perceptions of patients with CHD within a community-based setting about their condition and CR, and in the social support for this disease. Patients expressed expectations for professional guidance during CR, gained an understanding about the beneficial effects of emotional stability on cognitive function. Patients expressed their thoughts and feelings regarding the diversity of physical exercise options. Two main themes and seven sub-themes were identified: (a) "Insufficient CR resources for patients": Lack of awareness about CHD; inadequate knowledge about secondary prevention/CR; insufficient support from family and friends. (b) "Patient CR initiative": Patient self-adjustment; expectation of professional rehabilitation guidance; stable emotions improving cognition; diverse attitudes and awareness of exercise. Conclusion: For more effective CR, community-based medical teams should provide more comprehensive and individualized rehabilitation programs. They should focus on individual variations and preferences of patients, as well as enhance the autonomy of patients and improve their self-care ability through effective empowerment measures.

11.
Genomics ; 116(4): 110875, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38849018

RÉSUMÉ

Exploration of a stably expressed gene as a reference is critical for the accurate evaluation of miRNAs isolated from small extracellular vesicles (sEVs). In this study, we analyzed small RNA sequencing on plasma sEV miRNAs in the training dataset (n = 104) and found that miR-140-3p was the most stably expressed candidate reference for sEV miRNAs. We further demonstrated that miR-140-3p expressed most stably in the validation cohort (n = 46) when compared to two other reference miRNAs, miR-451a and miR-1228-3p, and the commonly-used miRNA reference U6. Finally, we compared the capability of miR-140-3p and U6 as the internal reference for sEV miRNA expression by evaluating key miRNAs expression in lung cancer patients and found that miR-140-3p was more suitable as a sEV miRNA reference gene. Taken together, our data indicated miR-140-3p as a stable internal reference miRNA of plasma sEVs to evaluate miRNA expression profiles in lung cancer patients.


Sujet(s)
Vésicules extracellulaires , Tumeurs du poumon , microARN , Humains , microARN/sang , microARN/génétique , Tumeurs du poumon/génétique , Tumeurs du poumon/sang , Vésicules extracellulaires/génétique , Vésicules extracellulaires/métabolisme , Femelle , Mâle , Normes de référence , Réaction de polymérisation en chaine en temps réel/normes , Adulte d'âge moyen , Marqueurs biologiques tumoraux/sang , Marqueurs biologiques tumoraux/génétique
12.
Sci Total Environ ; 938: 173389, 2024 Aug 15.
Article de Anglais | MEDLINE | ID: mdl-38810743

RÉSUMÉ

Climate change has profoundly affected the synchrony of tree growth at multiple scales, thereby altering the structure and function of forest ecosystems. The Asian boreal forests extend southward to the Greater Khingan Range in northeast China. Given the ecological importance and susceptibility to climate change, the impacts of warming on this marginal forest community have been extensively investigated. Nonetheless, how tree growth synchrony changes across this region remains less understood. Focusing on this knowledge gap, we compiled a contiguously-distributed tree-ring network, containing 18 sampling populations and 475 individual larch trees, to explore the changes in multiple-scale growth synchrony across this region. We found increasing growth synchrony at both the individual and population levels over the past decades. The increasing trend of the regional inter-population growth synchrony was well in line with the increasing temperature and PDSI. Furthermore, 11 of the 18 sampling populations showed significant increases in their intra-population growth synchrony. We further associated the sliding intra-population growth synchrony with local climates. Intra-population growth synchrony of 13 and 11 sampling populations were significantly positively correlated with local temperature, and negatively correlated with local PDSI, respectively, demonstrating the driving role of warming-induced drought on growth synchrony. The linear regression model quantifying this relationship suggested that an increase of 1 °C in annual mean temperature would drive the intra-population growth synchrony to increase by 0.047. As warming trends in the study area are projected to continue over this century, our study warns of the further consequences of the increasing growth synchrony may have on the functioning, resilience, and persistence of forests.


Sujet(s)
Changement climatique , Arbres , Chine , Arbres/croissance et développement , Taïga , Forêts , Réchauffement de la planète , Température , Écosystème
13.
Redox Biol ; 73: 103184, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38718533

RÉSUMÉ

RATIONALE: The disruption of the balance between fatty acid (FA) uptake and oxidation (FAO) leads to cardiac lipotoxicity, serving as the driving force behind diabetic cardiomyopathy (DbCM). Sirtuin 5 (Sirt5), a lysine de-succinylase, could impact diverse metabolic pathways, including FA metabolism. Nevertheless, the precise roles of Sirt5 in cardiac lipotoxicity and DbCM remain unknown. OBJECTIVE: This study aims to elucidate the role and underlying mechanism of Sirt5 in the context of cardiac lipotoxicity and DbCM. METHODS AND RESULTS: The expression of myocardial Sirt5 was found to be modestly elevated in diabetic heart failure patients and mice. Cardiac dysfunction, hypertrophy and lipotoxicity were exacerbated by ablation of Sirt5 but improved by forced expression of Sirt5 in diabetic mice. Notably, Sirt5 deficiency impaired FAO without affecting the capacity of FA uptake in the diabetic heart, leading to accumulation of FA intermediate metabolites, which mainly included medium- and long-chain fatty acyl-carnitines. Mechanistically, succinylomics analyses identified carnitine palmitoyltransferase 2 (CPT2), a crucial enzyme involved in the reconversion of fatty acyl-carnitines to fatty acyl-CoA and facilitating FAO, as the functional succinylated substrate mediator of Sirt5. Succinylation of Lys424 in CPT2 was significantly increased by Sirt5 deficiency, leading to the inactivation of its enzymatic activity and the subsequent accumulation of fatty acyl-carnitines. CPT2 K424R mutation, which mitigated succinylation modification, counteracted the reduction of enzymatic activity in CPT2 mediated by Sirt5 deficiency, thereby attenuating Sirt5 knockout-induced FAO impairment and lipid deposition. CONCLUSIONS: Sirt5 deficiency impairs FAO, leading to cardiac lipotoxicity in the diabetic heart through the succinylation of Lys424 in CPT2. This underscores the potential roles of Sirt5 and CPT2 as therapeutic targets for addressing DbCM.


Sujet(s)
Carnitine O-palmitoyltransferase , Cardiomyopathies diabétiques , Acides gras , Métabolisme lipidique , Myocytes cardiaques , Sirtuines , Animaux , Cardiomyopathies diabétiques/métabolisme , Cardiomyopathies diabétiques/génétique , Cardiomyopathies diabétiques/anatomopathologie , Carnitine O-palmitoyltransferase/métabolisme , Carnitine O-palmitoyltransferase/génétique , Sirtuines/métabolisme , Sirtuines/génétique , Souris , Acides gras/métabolisme , Myocytes cardiaques/métabolisme , Humains , Mâle , Oxydoréduction , Diabète expérimental/métabolisme , Diabète expérimental/complications
14.
J Agric Food Chem ; 72(22): 12445-12458, 2024 Jun 05.
Article de Anglais | MEDLINE | ID: mdl-38771652

RÉSUMÉ

Global water deficit is a severe abiotic stress threatening the yielding and quality of crops. Abscisic acid (ABA) is a phytohormone that mediates drought tolerance. Protein kinases and phosphatases function as molecular switches in eukaryotes. Protein phosphatases type 2C (PP2Cs) are a major family that play essential roles in ABA signaling and stress responses. However, the role and underlying mechanism of PP2C in rapeseed (Brassica napus L.) mediating drought response has not been reported yet. Here, we characterized a PP2C family member, BnaPP2C37, and its expression level was highly induced by ABA and dehydration treatments. It negatively regulates drought tolerance in rapeseed. We further identified that BnaPP2C37 interacted with multiple PYR/PYL receptors and a drought regulator BnaCPK5 (calcium-dependent protein kinase 5) through yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays. Specifically, BnaPYL1 and BnaPYL9 repress BnaPP2C37 phosphatase activity. Moreover, the pull-down assay and phosphatase assays show BnaPP2C37 interacts with BnaCPK5 to dephosphorylate BnaCPK5 and its downstream BnaABF3. Furthermore, a dual-luciferase assay revealed BnaPP2C37 transcript level was enhanced by BnaABF3 and BnaABF4, forming a negative feedback regulation to ABA response. In summary, we identified that BnaPP2C37 functions negatively in drought tolerance of rapeseed, and its phosphatase activity is repressed by BnaPYL1/9 whereas its transcriptional level is upregulated by BnaABF3/4.


Sujet(s)
Acide abscissique , Brassica napus , Sécheresses , Régulation de l'expression des gènes végétaux , Protéines végétales , Acide abscissique/métabolisme , Protéines végétales/métabolisme , Protéines végétales/génétique , Brassica napus/génétique , Brassica napus/métabolisme , Protein phosphatase 2C/métabolisme , Protein phosphatase 2C/génétique , Stress physiologique , Facteur de croissance végétal/métabolisme , Phosphoprotein Phosphatases/métabolisme , Phosphoprotein Phosphatases/génétique , Résistance à la sécheresse
15.
Acta Pharmacol Sin ; 2024 May 17.
Article de Anglais | MEDLINE | ID: mdl-38760544

RÉSUMÉ

Cardiac fibrosis is a detrimental pathological process, which constitutes the key factor for adverse cardiac structural remodeling leading to heart failure and other critical conditions. Circular RNAs (circRNAs) have emerged as important regulators of various cardiovascular diseases. It is known that several circRNAs regulate gene expression and pathological processes by binding miRNAs. In this study we investigated whether a novel circRNA, named circNSD1, and miR-429-3p formed an axis that controls cardiac fibrosis. We established a mouse model of myocardial infarction (MI) for in vivo studies and a cellular model of cardiac fibrogenesis in primary cultured mouse cardiac fibroblasts treated with TGF-ß1. We showed that miR-429-3p was markedly downregulated in the cardiac fibrosis models. Through gain- and loss-of-function studies we confirmed miR-429-3p as a negative regulator of cardiac fibrosis. In searching for the upstream regulator of miR-429-3p, we identified circNSD1 that we subsequently demonstrated as an endogenous sponge of miR-429-3p. In MI mice, knockdown of circNSD1 alleviated cardiac fibrosis. Moreover, silence of human circNSD1 suppressed the proliferation and collagen production in human cardiac fibroblasts in vitro. We revealed that circNSD1 directly bound miR-429-3p, thereby upregulating SULF1 expression and activating the Wnt/ß-catenin pathway. Collectively, circNSD1 may be a novel target for the treatment of cardiac fibrosis and associated cardiac disease.

16.
Infect Drug Resist ; 17: 1643-1652, 2024.
Article de Anglais | MEDLINE | ID: mdl-38707989

RÉSUMÉ

Purpose: The isolation rate of carbapenem-resistant Enterobacter cloacae complex (CREC) is continuously increasing. The aims of this study were to investigate the molecular characteristics and risk factors associated with CREC infections. Methods: Bacterial species were identified using the matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) (Bruker Daltonik GmbH, Bremen, Germany), and the hsp60 gene was utilized for further typing. Antimicrobial susceptibilities were assessed through the MicroScan WalkAway 96 Plus system (Siemens, Germany) and the microbroth dilution method. Antimicrobial resistance genes were screened through polymerase chain reaction (PCR), while the homologous relationship was assessed using multilocus sequence typing (MLST). Conjugation experiments were performed to verify whether the plasmid could be transferred. Additionally, logistic regression model was employed to analyze risk factors for CREC infections. Results: 32 strains of CREC bacteria were isolated during the study, yet only 20 were retained for preservation. While the isolates demonstrated resistance to the majority of antibiotics, they exhibited high sensitivity to polymyxin B and tigecycline. All isolates carried the blaNDM resistance gene, including 13 blaNDM-1 isolates and 7 blaNDM-5 isolates. MLST homology analysis revealed the presence of seven known ST types and one new ST type. Conjugation experiments confirmed that 13 isolates were capable of transferring the blaNDM resistance gene to Escherichia coli strain EC600. Single-factor analysis identified multiple primary risk factors for CREC infection, but multivariate analysis did not reveal independent risk factors. Conclusion: This study investigates the molecular characteristics and risk factors associated with CREC infections. The detection rate of CREC strains in our hospital is continuously rising and homology analysis suggested that strains might spread in our hospital, emphasizing the importance of implementing effective preventive measures to control the horizontal transmission of plasmid-mediated antimicrobial resistance genes.

18.
Article de Anglais | MEDLINE | ID: mdl-38702157

RÉSUMÉ

Introduction: Preeclampsia (PE) is a fundamental cause of preterm labor, intrauterine growth restriction, and persistent postpartum hypertension. In the present study, we aimed to investigate the correlation between 24-h urinary protein excretion, serum markers, and placental growth factor and their adverse pregnancy outcomes in patients with PE. Methods: A total of 126 pregnant women with PE (86 cases of mild PE and 40 cases of severe PE, assigned to the observation group) who came to our hospital from March 2019 to December 2021 for regular obstetric checkups and delivery were selected, with 60 healthy pregnant women assigned to the control group. Routine biochemical parameters, 24-h urinary protein quantification, serum parameters, and placental growth factor levels were recorded. The incidence of adverse neonatal pregnancy outcomes and abnormal fetal heart monitoring, neonatal body mass, 1 min Apgar score, and other adverse pregnancy outcomes were also analyzed in the different groups. Results: In comparison with healthy pregnant subjects, PE patients had earlier delivery gestational weeks (P < .05), significantly higher systolic blood pressure (SBP), diastolic blood pressure (DBP), 24-h urinary protein excretion, total cholesterol (TC), triglyceride (TG), D-Dimer and human chorionic gonadotropin (ß-hCG) levels (P < .05), lower albumin (ALB), platelet count, pregnant associated plasma protein A (PAPP-A) and placental growth factor (PLGF) (P < .05), and higher incidence of maternal and perinatal adverse outcomes (P < .05). Conclusions: Combined screening of 24-h urinary protein, PAPP-A, ß-hCG, PLGF, and serum indicators in early pregnancy are essential in predicting PE, allowing timely assessment of the risk of adverse pregnancy, and providing a basis for clinical intervention.

19.
ACS Nano ; 18(20): 13266-13276, 2024 May 21.
Article de Anglais | MEDLINE | ID: mdl-38709874

RÉSUMÉ

One key challenge in postoperative glioblastoma immunotherapy is to guarantee a potent and durable T-cell response, which is restricted by the immunosuppressive microenvironment within the lymph nodes (LNs). Here, we develop an in situ sprayed exosome-cross-linked gel that acts as an artificial LN structure to directly activate the tumor-infiltrating T cells for prevention of glioma recurrence. Briefly, this gel is generated by a bio-orthogonal reaction between azide-modified chimeric exosomes and alkyne-modified alginate polymers. Particularly, these chimeric exosomes are generated from dendritic cell (DC)-tumor hybrid cells, allowing for direct and robust T-cell activation. The gel structure with chimeric exosomes as cross-linking points avoids the quick clearance by the immune system and thus prolongs the durability of antitumor T-cell immunity. Importantly, this exosome-containing immunotherapeutic gel provides chances for ameliorating functions of antigen-presenting cells (APCs) through accommodating different intracellular-acting adjuvants, such as stimulator of interferon genes (STING) agonists. This further enhances the antitumor T-cell response, resulting in the almost complete elimination of residual lesions after surgery. Our findings provide a promising strategy for postsurgical glioma immunotherapy that warrants further exploration in the clinical arena.


Sujet(s)
Exosomes , Glioblastome , Immunothérapie , Noeuds lymphatiques , Exosomes/composition chimique , Glioblastome/thérapie , Glioblastome/immunologie , Glioblastome/anatomopathologie , Humains , Noeuds lymphatiques/immunologie , Noeuds lymphatiques/anatomopathologie , Animaux , Souris , Gels/composition chimique , Cellules dendritiques/immunologie , Lymphocytes T/immunologie , Lignée cellulaire tumorale , Tumeurs du cerveau/immunologie , Tumeurs du cerveau/thérapie , Tumeurs du cerveau/anatomopathologie , Souris de lignée C57BL
20.
Acta Pharmacol Sin ; 2024 May 27.
Article de Anglais | MEDLINE | ID: mdl-38802569

RÉSUMÉ

Graft-versus-host disease (GVHD), an immunological disorder that arises from donor T cell activation through recognition of host alloantigens, is the major limitation in the application of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Traditional immunosuppressive agents can relieve GVHD, but they induce serious side effects. It is highly required to explore alternative therapeutic strategy. Human amniotic epithelial stem cells (hAESCs) were recently considered as an ideal source for cell therapy with special immune regulatory property. In this study, we evaluated the therapeutic role of hAESCs in the treatment of GVHD, based on our previous developed cGMP-grade hAESCs product. Humanized mouse model of acute GVHD (aGVHD) was established by injection of huPBMCs via the tail vein. For prevention or treatment of aGVHD, hAESCs were injected to the mice on day -1 or on day 7 post-PBMC infusion, respectively. We showed that hAESCs infusion significantly alleviated the disease phenotype, increased the survival rate of aGVHD mice, and ameliorated pathological injuries in aGVHD target organs. We demonstrated that hAESCs directly induced CD4+ T cell polarization, in which Th1 and Th17 subsets were downregulated, and Treg subset was elevated. Correspondingly, the levels of a series of pro-inflammatory cytokines were reduced while the levels of the anti-inflammatory cytokines were upregulated in the presence of hAESCs. We found that hAESCs regulated CD4+ subset polarization in a paracrine mode, in which TGFß and PGE2 were selectively secreted to mediate Treg elevation and Th1/Th17 inhibition, respectively. In addition, transplanted hAESCs preserved the graft-versus-leukemia (GVL) effect by inhibiting leukemia cell growth. More intriguingly, hAESCs infusion in HSCT patients displayed potential anti-GVHD effect with no safety concerns and confirmed the immunoregulatory mechanisms in the preclinical study. We conclude that hAESCs infusion is a promising therapeutic strategy for post-HSCT GVHD without compromising the GVL effect. The clinical trial was registered at www.clinicaltrials.gov as #NCT03764228.

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