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1.
Plants (Basel) ; 13(15)2024 Jul 24.
Article de Anglais | MEDLINE | ID: mdl-39124154

RÉSUMÉ

Increased aboveground biomass is contingent on enhanced photosynthetically active radiation intercepted by the canopy (IPAR), improved radiation use efficiency (RUE), or both. We investigated whether and how optimized agronomic management practices promote IPAR and RUE. Four integrated agronomic management treatments, i.e., local traditional practice (LP), improved local traditional practice (ILP), high-yield agronomic management (HY), and improved high-yield agronomic management (IHY), were compared over two wheat (Triticum aestivum L.) growing seasons. The average grain yield obtained with IHY was 96% relative to that of HY and was 7% and 23% higher than that with ILP and LP, respectively. Both HY and IHY consistently supported large values of the leaf area index and IPAR fraction, thereby increasing total IPAR. Treatment HY showed increased pre-anthesis RUE, manifested as a higher specific leaf nitrogen content and whole-plant N nutrition index at anthesis. The highest pre-anthesis aboveground biomass was obtained with HY due to the highest pre-anthesis IPAR and RUE. Along with a higher canopy apparent photosynthetic rate, IHY produced higher post-anthesis aboveground biomass due to its higher post-anthesis IPAR and RUE. Treatment IHY had a slightly lower total IPAR but a similar total RUE and harvest index, thus producing a slightly lower grain yield relative to HY. These results demonstrate that the optimized agronomic management practice used under IHY effectively enhances radiation capture and improves radiation utilization. Additionally, the net profit for IHY was higher than that for HY, ILP, and LP by 8%, 11%, and 88%, respectively. Considering the high grain yield, high RUE and high economic benefits, we recommend IHY as the agronomic management practice in the target region, although further study of improvements in pre-anthesis RUE is required.

2.
J Cachexia Sarcopenia Muscle ; 15(1): 173-188, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-38009816

RÉSUMÉ

BACKGROUND: Handelin is a bioactive compound from Chrysanthemum indicum L. that improves motor function and muscle integrity during aging in Caenorhabditis elegans. This study aimed to further evaluate the protective effects and molecular mechanisms of handelin in a mouse muscle atrophy model induced by cachexia and aging. METHODS: A tumour necrosis factor (TNF)-α-induced atrophy model was used to examine handelin activity in cultured C2C12 myotubes in vitro. Lipopolysaccharide (LPS)-treated 8-week-old model mice and 23-month-old (aged) mice were used to examine the therapeutic effects of handelin on cachexia- and aging-induced muscle atrophy, respectively, in vivo. Protein and mRNA expressions were analysed by Western blotting, ELISA and quantitative PCR, respectively. Skeletal muscle mass was measured by histological analysis. RESULTS: Handelin treatment resulted in an upregulation of protein levels of early (MyoD and myogenin) and late (myosin heavy chain, MyHC) differentiation markers in C2C12 myotubes (P < 0.05), and enhanced mitochondrial respiratory (P < 0.05). In TNF-α-induced myotube atrophy model, handelin maintained MyHC protein levels, increased insulin-like growth factor (Igf1) mRNA expression and phosphorylated protein kinase B protein levels (P < 0.05). Handelin also reduced atrogin-1 expression, inhibited nuclear factor-κB activation and reduced mRNA levels of interleukin (Il)6, Il1b and chemokine ligand 1 (Cxcl1) (P < 0.05). In LPS-treated mice, handelin increased body weight (P < 0.05), the weight (P < 0.01) and cross-sectional area (CSA) of the soleus muscle (P < 0.0001) and improved motor function (P < 0.05). In aged mice, handelin slightly increased the weight of the tibialis anterior muscle (P = 0.06) and CSA of the tibialis anterior and gastrocnemius muscles (P < 0.0001). In the tibialis anterior muscle of aged mice, handelin upregulated mRNA levels of Igf1 (P < 0.01), anti-inflammatory cytokine Il10 (P < 0.01), mitochondrial biogenesis genes (P < 0.05) and antioxidant-related enzymes (P < 0.05) and strengthened Sod and Cat enzyme activity (P < 0.05). Handelin also reduced lipid peroxidation and protein carbonylation, downregulated mRNA levels of Fbxo32, Mstn, Cxcl1, Il1b and Tnf (P < 0.05), and decreased IL-1ß levels in serum (P < 0.05). Knockdown of Hsp70 or using an Hsp70 inhibitor abolished the ameliorating effects of handelin on myotube atrophy. CONCLUSIONS: Handelin ameliorated cachexia- and aging-induced skeletal muscle atrophy in vitro and in vivo, by maintaining homeostasis of protein synthesis and degradation, possibly by inhibiting inflammation. Handelin is a potentially promising drug candidate for the treatment of muscle wasting.


Sujet(s)
Cachexie , Homéostasie protéique , Terpènes , Animaux , Souris , Cachexie/traitement médicamenteux , Cachexie/étiologie , Cachexie/métabolisme , Lipopolysaccharides/métabolisme , Lipopolysaccharides/pharmacologie , Lipopolysaccharides/usage thérapeutique , Amyotrophie/traitement médicamenteux , Amyotrophie/étiologie , Amyotrophie/métabolisme , Muscles squelettiques/anatomopathologie , Facteur de nécrose tumorale alpha , Modèles animaux de maladie humaine , Inflammation/métabolisme , ARN messager/métabolisme
3.
Int J Mol Sci ; 25(1)2023 12 20.
Article de Anglais | MEDLINE | ID: mdl-38203268

RÉSUMÉ

Skeletal muscle differentiation is a precisely coordinated process. While many of the molecular details of myogenesis have been investigated extensively, the dynamic changes and functions of amino acids and related transporters remain unknown. In this study, we conducted a comprehensive analysis of amino acid levels during different time points of C2C12 myoblast differentiation using high-performance liquid chromatography (HPLC). Our findings revealed that the levels of most amino acids exhibited an initial increase at the onset of differentiation, reaching their peak typically on the fourth or sixth day, followed by a decline on the eighth day. Particularly, arginine and branched-chain amino acids showed a prominent increase during this period. Furthermore, we used RNA-seq analysis to show that the gene encoding the arginine transporter, Slc7a2, is significantly upregulated during differentiation. Knockdown of Slc7a2 gene expression resulted in a significant decrease in myoblast proliferation and led to a reduction in the expression levels of crucial myogenic regulatory factors, hindering the process of myoblast differentiation, fusion, and subsequent myotube formation. Lastly, we assessed the expression level of Slc7a2 during aging in humans and mice and found an upregulation of Slc7a2 expression during the aging process. These findings collectively suggest that the arginine transporter SLC7A2 plays a critical role in facilitating skeletal muscle differentiation and may hold potential as a therapeutic target for sarcopenia.


Sujet(s)
Acides aminés , Antifibrinolytiques , Animaux , Humains , Souris , Systèmes de transport d'acides aminés basiques/génétique , Acides aminés à chaine ramifiée , Arginine , Analyse de profil d'expression de gènes , Protéines de transport membranaire , RNA-Seq
4.
Int J Mol Sci ; 23(20)2022 Oct 20.
Article de Anglais | MEDLINE | ID: mdl-36293483

RÉSUMÉ

Natriuretic peptide receptor 1 (NPR1) serves as a modulator of vascular endothelial homeostasis. Interactions between monocytes and endothelial cells may initiate endothelium dysfunction, which is known as an early hallmark of atherosclerosis. In this study, we performed RNA-sequencing analysis for the aorta of Npr1 knockout (Npr1+/-) mice and found that differentially expressed genes were significantly related to cell adhesion. This result was supported by an increased expression of intercellular adhesion molecule 1 (ICAM-1) in the aortic endothelium of Npr1+/- mice. Moreover, we observed that the knockdown of NPR1 increased ICAM-1 expression and promoted THP-1 monocyte adhesion to human umbilical vein endothelial cells (HUVECs). NPR1 overexpression decreased ICAM-1 expression and inhibited the adhesion of monocytes to HUVECs treated by TNF-α (a cell adhesion inducer). Further analysis showed that adhesion-related genes were enriched in the focal adhesion signaling pathway, in which integrin beta 4 (Itgb4) was determined as a key gene. Notably, ITGB4 expression increased in vascular endothelium of Npr1+/- mice and in NPR1-knockdown HUVECs. The deficiency of ITGB4 decreased ICAM-1 expression and attenuated monocyte adhesion to NPR1-knockdown endothelial cells. Additionally, a reduced NPR1 and an increased ITGB4 expression level were found in an atherosclerosis mouse model. In conclusion, our findings demonstrate that NPR1 deficiency increases vascular endothelial cell adhesion by stimulating ITGB4 expression, which may contribute to the development of atherosclerosis.


Sujet(s)
Athérosclérose , Molécule-1 d'adhérence intercellulaire , Humains , Souris , Animaux , Molécule-1 d'adhérence intercellulaire/génétique , Molécule-1 d'adhérence intercellulaire/métabolisme , Endothélium vasculaire/métabolisme , Facteur de nécrose tumorale alpha/métabolisme , Monocytes/métabolisme , Adhérence cellulaire/génétique , Molécule-1 d'adhérence des cellules vasculaires/métabolisme , Cellules endothéliales de la veine ombilicale humaine/métabolisme , Athérosclérose/génétique , Athérosclérose/métabolisme , Intégrines/métabolisme , ARN/métabolisme
5.
Genes (Basel) ; 13(9)2022 08 24.
Article de Anglais | MEDLINE | ID: mdl-36140689

RÉSUMÉ

Endothelial cell senescence has a vital implication for vascular dysfunction, leading to age-related cardiovascular disease, especially hypertension and atherosclerosis. E2F transcription factor 2 (E2F2) plays a critical role in cell proliferation, differentiation, and DNA damage response. Up to date, no study has ever connected E2F2 to vascular endothelial cell senescence. Here, we demonstrate that E2F2 is involved in endothelial cellular senescence. We found that E2F2 expression is decreased during the replicative senescence of human umbilical vein endothelial cells (HUVECs) and the aortas of aged mice. The knockdown of E2F2 in young HUVECs induces premature senescence characterized by an increase in senescence-associated ß-galactosidase (SA-ß-gal) activity, a reduction in phosphorylated endothelial nitric oxide synthase (p-eNOS) and sirtuin 1 (SIRT1), and the upregulation of senescence-associated secretory phenotype (SASP) IL-6 and IL-8. The lack of E2F2 promoted cell cycle arrest, DNA damage, and cell proliferation inhibition. Conversely, E2F2 overexpression reversed the senescence phenotype and enhanced the cellular function in the senescent cells. Furthermore, E2F2 deficiency downregulated downstream target genes including CNNA2, CDK1, and FOXM1, and overexpression restored the expression of these genes. Our findings demonstrate that E2F2 plays an indispensable role in endothelial cell senescence.


Sujet(s)
Vieillissement de la cellule , Facteur de transcription E2F2 , Nitric oxide synthase type III , Sirtuine-1 , Animaux , Cellules cultivées , Vieillissement de la cellule/génétique , Facteur de transcription E2F2/génétique , Facteur de transcription E2F2/métabolisme , Cellules endothéliales de la veine ombilicale humaine/métabolisme , Humains , Interleukine-6 , Interleukine-8 , Souris , Nitric oxide synthase type III/métabolisme , Sirtuine-1/génétique , beta-Galactosidase
6.
Curr Med Sci ; 42(4): 871-884, 2022 Aug.
Article de Anglais | MEDLINE | ID: mdl-35451808

RÉSUMÉ

OBJECTIVE: This study aimed to identify microRNAs (miRNAs) involved in the development of perioperative neurocognitive disorders (PND). METHODS: Plasma exosomal miRNA expression was examined in patients before and after cardiopulmonary bypass (CPB) using microarray and qRT-PCR and these patients were diagnosed as PND later. Elderly rats were subjected to CPB, and the cognitive functions were examined. Bioinformatics analysis was conducted to predict the targets of miR-214-3p. Rats were administered rno-miR-214-3p agomir before or after CPB to investigate the role of miR-214-3p in PND development. RESULTS: We identified 76 differentially expressed plasma exosomal miRNAs in PND patients after surgery (P<0.05, ∣log2FC∣>0.58), including the upregulated hsa-miR-214-3p (P=0.002399392). Prostaglandin-endoperoxide synthase 2 (PTGS2) was predicted as a miR-214-3p target. In rats, CPB reduced the platform crossing numbers and target quadrant stay time, accompanied with hippocampal neuronal necrosis. The rno-miR-214-3p level was significantly increased in plasma exosomes but decreased in rat hippocampus after surgery, exhibiting a negative correlation (P<0.001, r=-0.762). A negative correlation between miR-214-3p and PTGS2 protein expression was also observed in the hippocampus after surgery. Importantly, rno-miR-214-3p agomir treatment, before or after surgery, significantly increased the platform crossing numbers (P=0.035) and target quadrant stay time (P=0.029) compared with negative control. Hippocampal PTGS2 protein level was increased in the untreated surgery group and decreased in response to rno-miR-214-3p agomir treatment before or after surgery (both P<0.05 vs. negative control). CONCLUSION: These data suggest that miR-214-3p/PTGS2 signaling contributes to the development of PND, serving as a potential therapeutic target for PND.


Sujet(s)
Pontage cardiopulmonaire , Exosomes , microARN , Troubles neurocognitifs , Animaux , Pontage cardiopulmonaire/effets indésirables , Biologie informatique , Cyclooxygenase 2/génétique , Exosomes/génétique , Humains , microARN/génétique , Troubles neurocognitifs/étiologie , Troubles neurocognitifs/génétique , Rats
7.
Biogerontology ; 23(1): 115-128, 2022 02.
Article de Anglais | MEDLINE | ID: mdl-35038074

RÉSUMÉ

Aging and aging-related disorders contribute to formidable socioeconomic and healthcare challenges. Several promising small molecules have been identified to target conserved genetic pathways delaying aging to extend lifespan and healthspan in many organisms. We previously found that extract from an edible and medicinal plant Chrysanthemum indicum L. (C. indicum L.) protect skin from UVB-induced photoaging, partially by reducing reactive oxygen species (ROS) generation. Thus, we hypothesized that C. indicum L. and its biological active compound may extend lifespan and health span in vivo. We find that both water and ethanol extracts from C. indicum L. extended lifespan of Caenorhabditis elegans, with better biological effect on life extending for ethanol extracts. As one of the major biological active compounds, handelin extended lifespan of C. elegans too. RNA-seq analysis revealed overall gene expression change of C. elegans post stimulation of handelin focus on several antioxidative proteins. Handelin significantly reduced ROS level and maintained the number and morphology of mitochondria. Moreover, handelin improveed many C. elegans behaviors related to healthspan, including increased pharyngeal pumping and body movement. Muscle fiber imaging analyses revealed that handelin maintains muscle architecture by stabilizing myofilaments. In conclusion, our present study finds a novel compound handelin, from C. indicum L., which bring about biologically beneficial effects by mild stress response, termed as hormetin, that can extend both lifespan and healthspan in vivo on C. elegans. Further study on mammal animal model of natural aging or sarcopenia will verify the potential clinical value of handelin.


Sujet(s)
Protéines de Caenorhabditis elegans , Caenorhabditis elegans , Animaux , Caenorhabditis elegans/physiologie , Protéines de Caenorhabditis elegans/génétique , Protéines de Caenorhabditis elegans/métabolisme , Éthanol/pharmacologie , Longévité/physiologie , Mammifères/métabolisme , Extraits de plantes/pharmacologie , Espèces réactives de l'oxygène/métabolisme , Terpènes
8.
Sci Total Environ ; 688: 136-142, 2019 Oct 20.
Article de Anglais | MEDLINE | ID: mdl-31229811

RÉSUMÉ

OBJECTIVES: We aimed to assess the effects of short-term and long-term exposure to ambient fine particle matter (PM2.5) on acute nasopharyngitis. METHODS: A total of 9468 participants aged 18 years and above were recruited from 10 communities in four cities of Guangdong, China during the baseline survey in 2014, and they were followed-up from January 2015 to December 2016. Air pollution exposure was assessed based on the daily concentrations (short-term) and annual concentrations (long-term) of the nearby air monitoring station and the survey date. A mixed-effect logistic model and Cox proportional hazards model were used to quantify the short-term and long-term associations after adjustment for potential confounding factors. RESULTS: Significantly positive associations were found between both short-term and long-term exposures of PM2.5 and acute nasopharyngitis. The adjusted odds ratio was 1.15 (95% CI: 1.07, 1.23) for each 10 µg/m3 increase in daily PM2.5 at lag2 day (short-term effects), and the hazard risk was 1.18 (95% CI: 1.10, 1.25) for each 10 µg/m3 increase in annual PM2.5 (long-term effects). Stronger associations between short-term PM2.5 exposure and acute nasopharyngitis were observed among men (OR = 1.10; 95% CI: 1.04, 1.17) and participants aged above 65 years (OR = 1.13; 95% CI: 1.04, 1.23) in the stratified analyses. No significant association was found in women (OR = 1.00; 95% CI: 0.92, 1.10) or young participants ≤65 years (OR = 0.96; 95% CI: 0.88, 1.04). However, for the long-term exposure, the hazard risk was higher for participants younger than 65 years (OR = 1.22; 95% CI: 1.12, 1.32) than the older group (OR = 1.11; 95% CI: 1.00, 1.24). CONCLUSION: This study indicates that both short-term and long-term exposures to higher concentrations of PM2.5 could increase the risk of acute nasopharyngitis.


Sujet(s)
Pollution de l'air/statistiques et données numériques , Exposition environnementale/statistiques et données numériques , Rhinopharyngite/épidémiologie , Matière particulaire/analyse , Adolescent , Adulte , Sujet âgé , Polluants atmosphériques/analyse , Chine/épidémiologie , Villes , Femelle , Humains , Modèles logistiques , Mâle , Adulte d'âge moyen , Facteurs temps
9.
Environ Sci Pollut Res Int ; 25(24): 24093-24100, 2018 Aug.
Article de Anglais | MEDLINE | ID: mdl-29948685

RÉSUMÉ

Currently, cucumber cultivation is mainly through monoculture, as continuous culture leads to the decrease of crop yield and soil quality. In order to improve soil quality to achieve continuous monocultures, soil physicochemical properties, microbial biomass, content of phenolic compounds, and the size of bacterial, fungal, ammonia-oxidizing bacteria (AOB), and Fusarium oxysporum were first evaluated in cucumber monoculture solar greenhouse. Soil improvement technology, including catch wheat (CW), calcium cyanamide disinfection (LN), and straw reactor technology (SR) during summer fallow period, was compared with conventional fallow (CK). Results showed that CW, LN, and SR all significantly increased soil pH, and LN and SR increased soil electrical conductivity (EC); however, CW decreased soil EC. Meanwhile, LN increased soil available N content significantly and SR increased available P content significantly. CW had negative effect on the accumulation of soil available nutrients, conversely, CW and SR had positive effect on the accumulation of microbial biomass carbon (MBC). All the treatments increased the total phenol content in the soil compared with CK. While CW increased the size of bacteria, AOB in the soil inhibited fungal and wilt pathogen size. LN also increased the size of soil bacteria and reduced the size of fungi. The comprehensive evaluation of all treatments showed that CW could control soil nutrient loss and improve the continuous cropping soil, making the soil transform from fungi to bacteria type. All the treatments accelerate the accumulation of phenolic compound, while whether or not developing autotoxicity requires further investigation.


Sujet(s)
Cucumis sativus/croissance et développement , Microbiologie du sol , Sol/composition chimique , Agriculture/instrumentation , Agriculture/méthodes , Ammoniac/métabolisme , Bactéries/métabolisme , Biomasse , Carbone/métabolisme , Cucumis sativus/composition chimique , Cyanamide/pharmacologie , Conductivité électrique , Champignons/métabolisme , Fusarium , Concentration en ions d'hydrogène , Hydroxybenzoates/analyse
10.
Front Chem ; 3: 53, 2015.
Article de Anglais | MEDLINE | ID: mdl-26389111

RÉSUMÉ

Nanocomposites are becoming a new paradigm in thermoelectric study: by incorporating nanophase(s) into a bulk matrix, a nanocomposite often exhibits unusual thermoelectric properties beyond its constituent phases. To date most nanophases are binary, while reports on ternary nanoinclusions are scarce. In this work, we conducted an exploratory study of introducing ternary (Ag2Te)x(Sb2Te3)1-x inclusions in the host matrix of Yb0.25Co4Sb12. Yb0.25Co4Sb12-4wt% (Ag2Te)x(Sb2Te3)1-x nanocomposites were prepared by a melting-milling-hot-pressing process. Microstructural analysis showed that poly-dispersed nanosized Ag-Sb-Te inclusions are distributed on the grain boundaries of Yb0.25Co4Sb12 coarse grains. Compared to the pristine nanoinclusion-free sample, the electrical conductivity, Seebeck coefficient, and thermal conductivity were optimized simultaneously upon nanocompositing, while the carrier mobility was largely remained. A maximum ZT of 1.3 was obtained in Yb0.25Co4Sb12-4wt% (Ag2Te)0.42(Sb2Te3)0.58 at 773 K, a ~ 40% increase compared to the pristine sample. The electron and phonon mean-free-path were estimated to help quantify the observed changes in the carrier mobility and lattice thermal conductivity.

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