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1.
Plant Physiol ; 193(2): 1491-1507, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37315209

RESUMO

Cold and drought stresses severely limit crop production and can occur simultaneously. Although some transcription factors and hormones have been characterized in plants subjected each stress, the role of metabolites, especially volatiles, in response to cold and drought stress exposure is rarely studied due to lack of suitable models. Here, we established a model for studying the role of volatiles in tea (Camellia sinensis) plants experiencing cold and drought stresses simultaneously. Using this model, we showed that volatiles induced by cold stress promote drought tolerance in tea plants by mediating reactive oxygen species and stomatal conductance. Needle trap microextraction combined with GC-MS identified the volatiles involved in the crosstalk and showed that cold-induced (Z)-3-hexenol improved the drought tolerance of tea plants. In addition, silencing C. sinensis alcohol dehydrogenase 2 (CsADH2) led to reduced (Z)-3-hexenol production and significantly reduced drought tolerance in response to simultaneous cold and drought stress. Transcriptome and metabolite analyses, together with plant hormone comparison and abscisic acid (ABA) biosynthesis pathway inhibition experiments, further confirmed the roles of ABA in (Z)-3-hexenol-induced drought tolerance of tea plants. (Z)-3-Hexenol application and gene silencing results supported the hypothesis that (Z)-3-hexenol plays a role in the integration of cold and drought tolerance by stimulating the dual-function glucosyltransferase UGT85A53, thereby altering ABA homeostasis in tea plants. Overall, we present a model for studying the roles of metabolites in plants under multiple stresses and reveal the roles of volatiles in integrating cold and drought stresses in plants.


Assuntos
Camellia sinensis , Resposta ao Choque Frio , Ácido Abscísico/metabolismo , Camellia sinensis/genética , Camellia sinensis/metabolismo , Secas , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Chá/metabolismo , Regulação da Expressão Gênica de Plantas
2.
NMR Biomed ; 37(3): e5059, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37872862

RESUMO

While single-shot late gadolinium enhancement (LGE) is useful for imaging patients with arrhythmia and/or dyspnea, it produces low spatial resolution. One approach to improve spatial resolution is to accelerate data acquisition using compressed sensing (CS). Our previous work described a single-shot, multi-inversion time (TI) LGE pulse sequence using radial k-space sampling and CS, but over-regularization resulted in significant image blurring that muted the benefits of data acceleration. The purpose of the present study was to improve the spatial resolution of the single-shot, multi-TI LGE pulse sequence by incorporating view sharing (VS) and k-space weighted contrast (KWIC) filtering into a GRASP-Pro reconstruction. In 24 patients (mean age = 61 ± 16 years; 9/15 females/males), we compared the performance of our improved multi-TI LGE and standard multi-TI LGE, where clinical standard LGE was used as a reference. Two clinical raters independently graded multi-TI images and clinical LGE images visually on a five-point Likert scale (1, nondiagnostic; 3, clinically acceptable; 5, best) for three categories: the conspicuity of myocardium or scar, artifact, and noise. The summed visual score (SVS) was defined as the sum of the three scores. Myocardial scar volume was quantified using the full-width at half-maximum method. The SVS was not significantly different between clinical breath-holding LGE (median 13.5, IQR 1.3) and multi-TI LGE (median 12.5, IQR 1.6) (P = 0.068). The myocardial scar volumes measured from clinical standard LGE and multi-TI LGE were strongly correlated (coefficient of determination, R2 = 0.99) and in good agreement (mean difference = 0.11%, lower limit of the agreement = -2.13%, upper limit of the agreement = 2.34%). The inter-rater agreement in myocardial scar volume quantification was strong (intraclass correlation coefficient = 0.79). The incorporation of VS and KWIC into GRASP-Pro improved spatial resolution. Our improved 25-fold accelerated, single-shot LGE sequence produces clinically acceptable image quality, multi-TI reconstruction, and accurate myocardial scar volume quantification.


Assuntos
Meios de Contraste , Gadolínio , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Cicatriz/patologia , Imageamento por Ressonância Magnética/métodos , Miocárdio/patologia
3.
Plant J ; 109(6): 1489-1506, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34931743

RESUMO

Cold and drought stress are the most critical stresses encountered by crops and occur simultaneously under field conditions. However, it is unclear whether volatiles contribute to both cold and drought tolerance, and if so, by what mechanisms they act. Here, we show that airborne eugenol can be taken up by the tea (Camellia sinensis) plant and metabolized into glycosides, thus enhancing cold and drought tolerance of tea plants. A uridine diphosphate (UDP)-glucosyltransferase, UGT71A59, was discovered, whose expression is strongly induced by multiple abiotic stresses. UGT71A59 specifically catalyzes glucosylation of eugenol glucoside in vitro and in vivo. Suppression of UGT71A59 expression in tea reduced the accumulation of eugenol glucoside, lowered reactive oxygen species (ROS) scavenging capacity, and ultimately impaired cold and drought stress tolerance. Exposure to airborne eugenol triggered a marked increase in UGT71A59 expression, eugenol glucoside accumulation, and cold tolerance by modulating ROS accumulation and CBF1 expression. It also promoted drought tolerance by altering abscisic acid homeostasis and stomatal closure. CBF1 and CBF3 play positive roles in eugenol-induced cold tolerance and CBF2 may be a negative regulator of eugenol-induced cold tolerance in tea plants. These results provide evidence that eugenol functions as a signal in cold and drought tolerance regulation and shed new light on the biological functions of volatiles in the response to multiple abiotic stresses in plants.


Assuntos
Camellia sinensis , Camellia sinensis/metabolismo , Temperatura Baixa , Secas , Eugenol/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico , Chá/metabolismo
4.
J Neurochem ; 164(5): 624-642, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36453259

RESUMO

Early life stress alters brain-derived neurotrophic factor (BDNF) promoter IV methylation and BDNF expression, which is closely related to the pathophysiological process of depression. However, the role of abnormal methylation of BDNF induced by stress during adolescence due to depression has not yet been clarified. In this study, adolescent mice were exposed to chronic unpredictable mild stress (CUMS). Depression-like behaviors, BDNF promoter IV methylation, expression of DNA methyltransferases (DNMTs), demethylation machinery enzymes, BDNF protein levels, and neuronal development in the prefrontal cortex (PFC) and hippocampus (HIP) were assessed in adolescent and adult mice. The DNMT inhibitor, 5-Aza-2-deoxycytidine (5-AzaD), was used as an intervention. Stress in adolescence induces behavioral dysfunction, elevated methylation levels of BDNF promoter IV, changes in the expression of DNMT, and demethylation machinery enzymes in adolescent and adult mice. Additionally, the stress in adolescence induced lower levels of BDNF and abnormal hippocampal doublecortin (DCX) expression in adolescent and adult mice. However, DNMT inhibitor treatment in adolescent-stressed mice relieved the abnormal behaviors, normalized the methylation level of BDNF promoter IV, BDNF protein expression, expression of DNMTs, and demethylation machinery enzymes, and improved the neuronal development of adult mice. These results suggest that stress in adolescence induces short- and long-term hypermethylation of BDNF promoter IV, which is regulated by DNMTs, and leads to the development of depression.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Córtex Pré-Frontal , Camundongos , Masculino , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Córtex Pré-Frontal/metabolismo , Metilação de DNA , Inibidores Enzimáticos , Hipocampo/metabolismo , Estresse Psicológico/metabolismo , Depressão/metabolismo , Modelos Animais de Doenças
5.
Biochem Biophys Res Commun ; 682: 250-258, 2023 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-37826948

RESUMO

Cathepsin D (CTSD) is an aspartic endopeptidase, however, we found that it was also capable of enzymatic digestion of nucleic acids (NAs). The purpose of this study was to investigate the basic properties of CTSD enzymatic activity on NAs, and explore the degradation mechanism. The results showed that NAs were efficiently digested between pH 3.0 and 5.0, and the optimum pH was 3.5. CTSD exhibited optimum activity at the temperature of 50°C. The degradation rate was improved with an increased CTSD concentration, and NAs were digested to an enzyme concentration of 0.001%, at which point, NAs were no longer digested. Ca2+ and Mg2+ at low concentrations of 5 mM promoted the digestion remarkably. As the protein substrate for CTSD, both Hb and BSA had no effect on DNA degradation, even when the molar ratio of protein:DNA was 104:1. Kinetic parameters of Km and kcat/Km value were (42 ± 1) µM and (1.62 ± 0.1) × 10-2 s-1mM-1 respectively, using real-time quantitative PCR (RT-PCR). Specially, pepstatin A which is the specific aspartic protease inhibitor exhibited inhibitory effect on NA digestion by CTSD as well, suggesting that the catalytic active site of CTSD for NAs might be the same as protein. A brief degradation mechanism is discussed. The present study may change the cognition of CTSD specificity for substrate and contribute greatly to enzymology of CTSD.


Assuntos
Catepsina D , Ácidos Nucleicos , Ácido Aspártico Endopeptidases , Catepsina D/metabolismo , DNA/metabolismo , Humanos , Animais , Bovinos
6.
Plant Physiol ; 188(3): 1507-1520, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-34893910

RESUMO

Plant immune response following pathogenic infection is regulated by plant hormones, and salicylic acid (SA) and its sugar conjugates play important roles in establishing basal resistance. Here, the important pathogen Pseudopestalotiopsis camelliae-sinensis (Pcs) was isolated from tea gray blight, one of the most destructive diseases in tea plantations. Transcriptomic analysis led to the discovery of the putative Camellia sinensis UDP-glucosyltransferase CsUGT87E7 whose expression was significantly induced by SA application and Pcs infection. Recombinant CsUGT87E7 glucosylates SA with a Km value of 12 µM to form SA glucose ester (SGE). Downregulation reduced the accumulation of SGE, and CsUGT87E7-silenced tea plants exhibited greater susceptibility to pathogen infection than control plants. Similarly, CsUGT87E7-silenced tea leaves accumulated significantly less SA after infection and showed reduced expression of pathogenesis-related genes. These results suggest that CsUGT87E7 is an SA carboxyl glucosyltransferase that plays a positive role in plant disease resistance by modulating SA homeostasis through a mechanism distinct from that described in Arabidopsis (Arabidopsis thaliana). This study provides insight into the mechanisms of SA metabolism and highlights the role of SGE in the modulation of plant disease resistance.


Assuntos
Ascomicetos/patogenicidade , Camellia sinensis/genética , Camellia sinensis/metabolismo , Camellia sinensis/microbiologia , Resistência à Doença/genética , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Ácido Salicílico/metabolismo , China , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Produtos Agrícolas/microbiologia , Resistência à Doença/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Genótipo , Doenças das Plantas/microbiologia
7.
Anal Chem ; 94(12): 5122-5131, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35306816

RESUMO

The levels of l-arginine and asymmetric dimethylarginine (ADMA) and the amount of the nitric oxide (NO) production have recently been linked to breast cancer and pharmaceutical effect evaluation. Herein, a method combining electrochemistry and high-resolution mass spectrometry (HRMS) was established and used to study NO metabolism and its modulation by ginsenoside compound K (CK) in breast cancer cells. Platinum nanoparticles-decorated fluorine tin oxide was employed as an electrochemical sensor for in situ detection of NO release, while HRMS was used for the analysis of the NO-related metabolites. Through the combination of the electrochemical and HRMS results, decreases in arginine and NO and increases in ADMA and ornithine were observed after modulation by CK, and two highly correlated metabolic pathways including arginine and proline metabolism and vascular smooth muscle contraction were found. This method offers a new strategy for fast evaluation of pharmaceutical efficacy based on NO metabolism.


Assuntos
Neoplasias da Mama , Nanopartículas Metálicas , Arginina/química , Neoplasias da Mama/tratamento farmacológico , Eletroquímica , Feminino , Ginsenosídeos , Humanos , Óxido Nítrico/metabolismo , Preparações Farmacêuticas , Platina , Espectrometria de Massas em Tandem/métodos
8.
Plant Biotechnol J ; 20(11): 2089-2106, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35810348

RESUMO

The tea plant is an economically important woody beverage crop. The unique taste of tea is evoked by certain metabolites, especially catechin esters, whereas their precise formation mechanism in different cell types remains unclear. Here, a fast protoplast isolation method was established and the transcriptional profiles of 16 977 single cells from 1st and 3rd leaves were investigated. We first identified 79 marker genes based on six isolated tissues and constructed a transcriptome atlas, mapped developmental trajectories and further delineated the distribution of different cell types during leaf differentiation and genes associated with cell fate transformation. Interestingly, eight differently expressed genes were found to co-exist at four branch points. Genes involved in the biosynthesis of certain metabolites showed cell- and development-specific characteristics. An unexpected catechin ester glycosyltransferase was characterized for the first time in plants by a gene co-expression network in mesophyll cells. Thus, the first single-cell transcriptional landscape in woody crop leave was reported and a novel metabolism pathway of catechin esters in plants was discovered.


Assuntos
Catequina , Catequina/genética , Catequina/metabolismo , Transcriptoma/genética , Regulação da Expressão Gênica de Plantas/genética , Ésteres/metabolismo , Proteínas de Plantas/genética , Folhas de Planta/genética , Folhas de Planta/metabolismo , Redes e Vias Metabólicas , Chá/genética , Chá/metabolismo
9.
Haemophilia ; 28(5): 726-736, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35714660

RESUMO

AIM: To predict the long-term benefits and economic costs of the improvements in haemophilia care in China demonstrated by increasing use of prophylaxis, compared with the current status. METHODS: City-level predictions from 2018 to 2033 were conducted for five representative cities in China. The long-term clinical and economic outcomes in the scenario where haemophilia care has significantly improved and the existing scenario of haemophilia care were calculated and compared. The model input data were obtained from local records, expert interviews, published literature, and other sources. Outcome measures including number of bleeds and joint bleeds, number of target joints, disability rate, direct and indirect costs were calculated at the patient and population levels. RESULTS: The long-term predictions for 2033 demonstrated significantly improved bleed control and joint outcomes due to increased use of prophylaxis. The total number of averted bleed events per patient ranged from 3.9 in Shenyang to 16.1 in Zhengzhou in 2033, and the population-level averted bleed events ranged from 1963 in Xiamen to 14,868 in Zhengzhou. The treatment improvement also leads to significant economic costs driven by increase in clotting factor costs (more than 90%). At the population level, the additional total costs were highest in Zhengzhou (CNY 177.4 million) and lowest in Shenyang (CNY 45.4 million), due to their different population sizes and various existing treatment regimens. The outpatient and hospitalization costs decreased, while the factor costs increased. CONCLUSION: The long-term prophylaxis is associated with avoided bleed events and disabilities. The improved treatment regimens are also associated with a significant economic burden, driven by factor costs.


Assuntos
Hemofilia A , Fatores de Coagulação Sanguínea/uso terapêutico , Fator VIII/uso terapêutico , Hemartrose/complicações , Hemofilia A/complicações , Hemofilia A/tratamento farmacológico , Hemorragia/complicações , Hospitalização , Humanos
10.
J Sep Sci ; 45(14): 2446-2457, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35503988

RESUMO

An herbal prescription is usually composed of several herbal medicines. The complex and diverse components bring great challenges to its bioactivity study. To comprehensively analyze the bioactivity of an herbal prescription, a new strategy based on peak-by-peak cutting and knock-out chromatography was proposed. In this strategy, active compounds were screened out via peak-by-peak cutting from an herbal extract, and the influence of a compound on the overall activity of the herbal extract was evaluated by knock-out chromatography. Qiliqiangxin capsule is an herbal prescription composed of 11 herbal medicines for the treatment of chronic heart failure. A total of 71 peaks were collected through peak-by-peak cutting, and each peak was identified by a high-resolution mass spectrum. The bioassay against 1,1-diphenyl-2-picrylhydrazyl showed that two types of compounds namely salvianolic acids and caffeoylquinic acids were potent scavengers. Knock-out chromatography suggested that the removal of one single compound had no obvious influence on the overall activity of the Qiliqiangxin capsule. After all the main peaks in the Qiliqiangxin capsule were knocked out, the remaining part still exhibited a potent activity, indicating high activity stability of the Qiliqiangxin capsule. The proposed strategy is helpful for the comprehensive analysis of the bioactivity of other herbal prescriptions.


Assuntos
Medicamentos de Ervas Chinesas , Plantas Medicinais , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Plantas Medicinais/química , Prescrições
11.
Reprod Domest Anim ; 57(11): 1440-1449, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36317481

RESUMO

Increased palmitic acid (PA) levels have been found in females with reduced fertility due to metabolic disorders. However, effective antioxidant astaxanthin (AXE) might positively affect animal reproduction. Therefore, the present study was designed to evaluate the impact of a high concentration of PA on oocyte maturation and the possible protective effect of AXE against high PA concentration in pigs. Firstly, different concentrations (0.2, 0.5, 0.8 mM) of PA were conducted on in vitro maturation (IVM) of pig oocytes (PA0.2, PA0.5, and PA0.8), while no addition of PA was performed as the control group (Ctrl). Results showed that the cumulus cell expansion index (CCEI) was lower in PA0.5 and PA0.8 groups compared to Ctrl group (p < .05). In PA0.5 group, not only did the percentage of matured oocytes with the first polar body (PB1) reduced, that with more oocytes arrested at germinal vesicle (GV) stage (53.44% ± 7.16% vs. 20.93% ± 5.16%, p < .05), but also a higher number of transzonal projections (TZPs) was observed in PA0.5 than Ctrl group. Besides, supplement of PA resulted in a dose-dependent decrease in mitochondrial activity. Although no difference of lipid content was observed between PA0.5 and Ctrl groups, the lipid content was at a higher level in PA0.2 group than in the other three groups. Hence, concentration of 0.5 mM of PA was performed in the following experiments, and 2.5 µM AXE carried out to investigate the possible relief effects of PA (PA0.5 + AXE). Results showed that the percentage of matured oocytes with PB1 was higher in PA0.5 + AXE than in PA0.5 group (63.43% ± 1.50% vs. 55.33% ± 0.81%, p < .01), and ROS levels both in oocytes and their cumulus cells (CCs) reduced in PA0.5 + AXE when compared to PA0.5 group. In addition, the rate of CCs with apoptosis decreased in PA0.5 + AXE, and the expression level of caspase 3 and BAX was lower than PA0.5 group. In conclusion, the maturation of pig oocytes was inhibited by the high concentration of PA; however, this negative effect of PA-induced might be relieved by the supplement of AXE.


Assuntos
Técnicas de Maturação in Vitro de Oócitos , Ácido Palmítico , Feminino , Animais , Suínos , Técnicas de Maturação in Vitro de Oócitos/veterinária , Técnicas de Maturação in Vitro de Oócitos/métodos , Ácido Palmítico/farmacologia , Ácido Palmítico/metabolismo , Células do Cúmulo , Oócitos
12.
Ren Fail ; 44(1): 1376-1387, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35969012

RESUMO

Renal ischemia-reperfusion injury (IRI) is a common prerequisite of acute renal injury (AKI) that involves the entire system and induces critical illness. The C domain of insulin-like growth factor-1 (IGF-1C) plays an important role in promoting angiogenesis and enhancing the inflammatory response. However, given the shortcomings of its short half-life and poor stability, the application of IGF-1C is restricted. In the present study, IGF-1C nanoparticles (NP-IGF-1C) were constructed by combining 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[maleimide (polye thyleneglycol)](DSPE-PEG-MAL) and IGF-1C through a Michael addition reaction to evaluate the effects of NP-IGF-1C on preventing IRI. In vitro studies have shown that NP-IGF-1C is not cytotoxic and protects cells from oxidative damage. The renal enrichment and biocompatibility of NP-IGF-1C were determined in vivo by connecting fluorescent molecules to NP-IGF-1C for in vivo imaging and pathological staining of important organs. After IRI, renal function decreased, and inflammatory cell infiltration, oxidative stress and apoptosis increased. As expected, NP-IGF-1C reversed these changes, indicating that NP-IGF-1C played a protective role in the process of IRI, which may be mediated by its antioxidant, anti-inflammatory and antiapoptotic activities.


Assuntos
Injúria Renal Aguda , Nanopartículas , Traumatismo por Reperfusão , Injúria Renal Aguda/patologia , Animais , Rim , Camundongos , Estresse Oxidativo , Traumatismo por Reperfusão/metabolismo
13.
Angew Chem Int Ed Engl ; 61(21): e202116059, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35261133

RESUMO

Achieving efficient catalytic conversion over a heterogeneous catalyst with excellent resistance against leaching is still a grand challenge for sustainable chemical synthesis in aqueous solution. Herein, we devised a single-atom Pt1 /hydroxyapatite (HAP) catalyst via a simple hydrothermal strategy. Gratifyingly, this robust Pt1 /HAP catalyst exhibits remarkable catalytic selectivity and catalyst stability for the selective oxidation of C2 -C4 polyols to corresponding primary hydroxy acids. It is found that the Pt-(O-P) linkages with strong electron-withdrawing function of PO4 3- (Pt1 -OPO4 3- pair active site) not only realize the activation of the C-H bond, but also destabilize the transition state from adsorbed hydroxy acids toward the C-C cleavage, resulting in the sharply increased selectivity of hydroxy acids. Moreover, the strong PO4 3- -coordination effect provides electrostatic stabilization for single-atom Pt, ensuring the highly efficient catalysis of Pt1 /HAP for over 160 hours with superior leaching resistance.

14.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(7): 728-735, 2022 Jul 15.
Artigo em Chinês | MEDLINE | ID: mdl-35894185

RESUMO

OBJECTIVES: To investigate the psychological and behavioral problems and related influencing factors in children and adolescents during the coronavirus disease 2019 (COVID-19) epidemic. METHODS: China National Knowledge Infrastructure, Wanfang Data, PubMed, and Web of Science were searched using the method of subject search for articles published up to March 31, 2022, and related data were extracted for Scoping review. RESULTS: A total of 3 951 articles were retrieved, and 35 articles from 12 countries were finally included. Most of the articles were from the journals related to pediatrics, psychiatry, psychology, and epidemiology, and cross-sectional survey was the most commonly used research method. Psychological and behavioral problems in children and adolescents mainly included depression/anxiety/stress, sleep disorder, internet behavior problems, traumatic stress disorder, and self-injury/suicide. Influencing factors were analyzed from the three aspects of socio-demographic characteristics, changes in living habits, and ways of coping with COVID-19. CONCLUSIONS: During the COVID-19 epidemic, the psychological and behavioral problems of children and adolescents in China and overseas are severe. In the future, further investigation and research can be carried out based on relevant influencing factors to improve the psychological and behavioral problems.


Assuntos
COVID-19 , Comportamento Problema , Adolescente , Ansiedade/epidemiologia , Ansiedade/etiologia , Criança , China/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Humanos , Saúde Mental
15.
J Neuroinflammation ; 18(1): 254, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34736493

RESUMO

BACKGROUND: Chronic unpredictable mild stress (CUMS) can not only lead to depression-like behavior but also change the composition of the gut microbiome. Regulating the gut microbiome can have an antidepressant effect, but the mechanism by which it improves depressive symptoms is not clear. Short-chain fatty acids (SCFAs) are small molecular compounds produced by the fermentation of non-digestible carbohydrates. SFCAs are ubiquitous in intestinal endocrine and immune cells, making them important mediators of gut microbiome-regulated body functions. The balance between the pro- and anti-inflammatory microglia plays an important role in the occurrence and treatment of depression caused by chronic stress. Non-absorbable antibiotic rifaximin can regulate the structure of the gut microbiome. We hypothesized that rifaximin protects against stress-induced inflammation and depression-like behaviors by regulating the abundance of fecal microbial metabolites and the microglial functions. METHODS: We administered 150 mg/kg rifaximin intragastrically to rats exposed to CUMS for 4 weeks and investigated the composition of the fecal microbiome, the content of short-chain fatty acids in the serum and brain, the functional profiles of microglia and hippocampal neurogenesis. RESULTS: Our results show that rifaximin ameliorated depressive-like behavior induced by CUMS, as reflected by sucrose preference, the open field test and the Morris water maze. Rifaximin increased the relative abundance of Ruminococcaceae and Lachnospiraceae, which were significantly positively correlated with the high level of butyrate in the brain. Rifaximin increased the content of anti-inflammatory factors released by microglia, and prevented the neurogenic abnormalities caused by CUMS. CONCLUSIONS: These results suggest that rifaximin can regulate the inflammatory function of microglia and play a protective role in pubertal neurodevelopment during CUMS by regulating the gut microbiome and short-chain fatty acids.


Assuntos
Eixo Encéfalo-Intestino/efeitos dos fármacos , Depressão , Fármacos Gastrointestinais/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Microglia/metabolismo , Rifaximina/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Eixo Encéfalo-Intestino/fisiologia , Depressão/etiologia , Microbioma Gastrointestinal/fisiologia , Masculino , Microglia/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Estresse Psicológico/complicações
16.
Plant Cell Environ ; 44(4): 1178-1191, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32713005

RESUMO

Herbivore-induced plant volatiles play important ecological roles in defense against stresses. However, if and which volatile(s) are involved in the plant-plant communication in response to herbivorous insects in tea plants remains unknown. Here, plant-plant communication experiments confirm that volatiles emitted from insects-attacked tea plants can trigger plant resistance and reduce the risk of herbivore damage by inducing jasmonic acid (JA) accumulation in neighboring plants. The emission of six compounds was significantly induced by geometrid Ectropis obliqua, one of the most common pests of the tea plant in China. Among them, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) could induce the accumulation of JA and thus promotes the resistance of neighboring intact plants to herbivorous insects. CsCYP82D47 was identified for the first time as a P450 enzyme, which catalyzes the final step in the biosynthesis of DMNT from (E)-nerolidol. Down-regulation of CsCYP82D47 in tea plants resulted in a reduced accumulation of DMNT and significantly reduced the release of DMNT in response to the feeding of herbivorous insects. The first evidence for plant-plant communication in response to herbivores in tea plants will help to understand how plants respond to volatile cues in response to herbivores and provide new insight into the role(s) of DMNT in tea plants.


Assuntos
Alcenos/metabolismo , Camellia sinensis/metabolismo , Ciclopentanos/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Oxilipinas/metabolismo , Defesa das Plantas contra Herbivoria , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Animais , Camellia sinensis/genética , Camellia sinensis/fisiologia , Clonagem Molecular , Comunicação , Sistema Enzimático do Citocromo P-450/genética , Regulação da Expressão Gênica de Plantas , Larva , Mariposas , Reguladores de Crescimento de Plantas/fisiologia , Proteínas de Plantas/genética , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Compostos Orgânicos Voláteis/metabolismo
17.
Opt Express ; 29(12): 17775-17783, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34154053

RESUMO

We demonstrate the high quality (Q) factor microdisk resonators in high index-contrast chalcogenide glass (ChG) film GeSbSe using electron-beam lithography followed by plasma dry etching. High confinement, low-loss, and single-point-coupled microdisk resonators with a loaded Q factor of 5×105 are measured. We also present pulley-coupled microdisk resonators for relaxing the requirements on the coupling gap. While adjusting the wrap-around coupling waveguides to be phase-matched to the resonator mode, a single specific microdisk radial mode can be excited. Moreover, the thermal characterization of microdisk resonators is carried out to estimate the thermo-optic coefficient of 6.7×10-5/K for bulk ChG.

18.
Nanotechnology ; 32(49)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34450603

RESUMO

Electrons can degrade pentachlorphenate sodium (PCPNa) directly or activate molecular oxygen to produce·O2-and ·OH for its degradation. However, less work has been performed to control such two kinds of reaction pathway by modifying BiOCl. Herein, we firstly regulated the reaction pathway between electrons and PCPNa by adjusting the amount of surface oxygen vacancies (OVs) and surface adsorbed hydroxyl groups in I-doped BiOCl exposed with different facets. OVs on (001) facets-exposed I-doped BiOCl enabled large amount of PCPNa to adsorb on its surface and facilitated the direct reaction between electrons and PCPNa. In contrary, more surface adsorbed hydroxyl groups and oxygen on (010) facets-exposed I-doped BiOCl can retard the direct reaction between electrons and PCPNa via lowering the adsorption of PCPNa and increasing the activation of molecular oxygen by electrons. Although more·O2-and ·OH generated in I-doped (010)-facets exposed BiOCl, I-doped (001)-facets exposed BiOCl exhibited better photocatalytic activity. We proposed that the direct reaction between electrons and PCPNa can enhance the utilization efficiency of photogenerated electrons and improve photocatalytic degradation efficiency of PCPNa.

19.
J Cell Mol Med ; 24(13): 7301-7312, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32463592

RESUMO

Cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-activated Cl- channel, is extensively expressed in the epithelial cells of various tissues and organs. Accumulating evidence indicates that aberrant expression or mutation of CFTR is related to carcinoma development. Malignant gliomas are the most common and aggressive intracranial tumours; however, the role of CFTR in the development of malignant gliomas is unclear. Here, we report that CFTR is expressed in malignant glioma cell lines. Suppression of CFTR channel function or knockdown of CFTR suppresses glioma cell viability whereas overexpression of CFTR promotes it. Additionally, overexpression of CFTR suppresses apoptosis and promotes glioma progression in both subcutaneous and orthotopic xenograft models. Cystic fibrosis transmembrane conductance regulator activates Akt/Bcl2 pathway, and suppression of PI3K/Akt pathway abolishes CFTR overexpression-induced up-regulation of Bcl2 (MK-2206 and LY294002) and cell viability (MK-2206). More importantly, the protein expression level of CFTR is significantly increased in glioblastoma patient samples. Altogether, our study has revealed a mechanism by which CFTR promotes glioma progression via up-regulation of Akt/Bcl2-mediated anti-apoptotic pathway, which warrants future studies into the potential of using CFTR as a therapeutic target for glioma treatment.


Assuntos
Apoptose/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Glioma/genética , Glioma/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Regulação para Cima/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos Nus
20.
New Phytol ; 226(2): 362-372, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31828806

RESUMO

Plants produce and emit terpenes, including sesquiterpenes, during growth and development, which serve different functions in plants. The sesquiterpene nerolidol has health-promoting properties and adds a floral scent to plants. However, the glycosylation mechanism of nerolidol and its biological roles in plants remained unknown. Sesquiterpene UDP-glucosyltransferases were selected by using metabolites-genes correlation analysis, and its roles in response to cold stress were studied. We discovered the first plant UGT (UGT91Q2) in tea plant, whose expression is strongly induced by cold stress and which specifically catalyzes the glucosylation of nerolidol. The accumulation of nerolidol glucoside was consistent with the expression level of UGT91Q2 in response to cold stress, as well as in different tea cultivars. The reactive oxygen species (ROS) scavenging capacity of nerolidol glucoside was significantly higher than that of free nerolidol. Down-regulation of UGT91Q2 resulted in reduced accumulation of nerolidol glucoside, ROS scavenging capacity and tea plant cold tolerance. Tea plants absorbed airborne nerolidol and converted it to its glucoside, subsequently enhancing tea plant cold stress tolerance. Nerolidol plays a role in response to cold stress as well as in triggering plant-plant communication in response to cold stress. Our findings reveal previously unidentified roles of volatiles in response to abiotic stress in plants.


Assuntos
Camellia sinensis , Glucosiltransferases , Sesquiterpenos , Camellia sinensis/enzimologia , Resposta ao Choque Frio , Regulação da Expressão Gênica de Plantas , Glucosiltransferases/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Chá
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