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1.
Front Mol Biosci ; 11: 1274850, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38523661

RESUMO

Mammalian cytosolic thioredoxin reductase (TrxR1) serves as an antioxidant protein by transferring electrons from NADPH to various substrates. The action of TrxR1 is achieved via reversible changes between NADPH-reduced and non-reduced forms, which involves C-terminal selenolthiol/selenenylsulfide exchanges. TrxR1 may be released into extracellular environment, where TrxR1 is present mainly in the non-reduced form with active-site disulfide and selenenylsulfide bonds. The relationships between extracellular TrxR1 and tumor metastasis or cellular signaling have been discovered, but there are few reports on small-molecule compounds in targeted the non-reduced form of TrxR1. Using eight types of small-molecule thiol-reactive reagents as electrophilic models, we report that the selenenylsulfide bond in the non-reduced form of TrxR1 functions as a selector for the thiol-reactive reagents at pH 7.5. The non-reduced form of TrxR1 is resistant to hydrogen peroxide/oxidized glutathione, but is sensitive to certain electrophilic reagents in different ways. With 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB) and S-nitrosoglutathione (GSNO), the polarized selenenylsulfide bond breaks, and selenolate anion donates electron to the dynamic covalent bond in DTNB or GSNO, forming TNB-S-Se-TrxR1 complex or ON-Se-TrxR1 complex. The both complexes lose the ability to transfer electrons from NADPH to substrate. For diamide, the non-reduced TrxR1 actually prevents irreversible damage by this oxidant. This is consistent with the regained activity of TrxR1 through removal of diamide via dialysis. Diamide shows effective in the presence of human cytosolic thioredoxin (hTrx1), Cys residue(s) of which is/are preferentially affected by diamide to yield disulfide, hTrx1 dimer and the mixed disulfide between TrxR1-Cys497/Sec498 and hTrx1-Cys73. In human serum samples, the non-reduced form of TrxR1 exists as dithiothreitol-reducible polymer/complexes, which might protect the non-reduced TrxR1 from inactivation by certain electrophilic reagents under oxidative conditions, because cleavage of these disulfides can lead to regain the activity of TrxR1. The details of the selective response of the selenenylsulfide bond to electrophilic reagents may provide new information for designing novel small-molecule inhibitors (drugs) in targeted extracellular/non-reduced TrxR1.

2.
Sci Rep ; 14(1): 5894, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38467703

RESUMO

Global climate change associated with increased carbon emissions has become a global concern. Resource-based cities, by estimations, have emerged as major contributors to carbon emissions, accounting for approximately one-third of the national total. This underscores their pivotal role in the pursuit of carbon neutrality goals. Despite this, resource-based cities have long been neglected in current climate change mitigation policy discussions. Accordingly, using exploratory spatial data analysis and Geographical Weighted Regression method, this study investigates the determinants of carbon emissions and their spatial pattern in 113 resource-based cities in China. It can be concluded that: (1) The proportion of carbon emissions from resource-based cities in the national total has shown a marginal increase between 2003 and 2017, and the emissions from these cities have not yet reached their peak. (2) A relatively stable spatial pattern of "northeast high, southwest low" characterizes carbon emissions in resource-based cities, displaying significant spatial autocorrelation. (3) Population size, economic development level, carbon abatement technology, and the proportion of resource-based industries all contribute to the increase in carbon emissions in these cities, with carbon abatement technology playing a predominant role. (4) There is a spatial variation in the strength of the effects of the various influences.

3.
Case Rep Oncol ; 17(1): 361-369, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38415271

RESUMO

Introduction: Cadonilimab (AK104) is an innovative human programmed cell death-1 (PD-1)/cytotoxic T lymphocyte antigen-4 (CTLA-4) bispecific antibody. Compared with the combination therapy of PD-1 and CTLA-4 blockers, less cellular toxicity of cadonilimab was significantly manifested. As one of the characteristic adverse effects of cadonilimab, infusion-related reactions (IRRs) represent fever, chills, rash, decreased blood pressure, and other symptoms. Case Presentation: Here, we documented seven cases of IRRs after the administration of cadonilimab. The symptoms of IRRs were relieved after the discontinuation of cadonilimab and the administration of diphenhydramine, dexamethasone, and cimetidine. Notably, 3 patients were able to tolerate the subsequent cadonilimab therapy under the pretreatment. Conclusion: In this study, we discovered that cadonilimab-related IRRs might be lessened or prevented by administering medication and the proper pretreatment and lowering the infusion rate.

4.
Phys Chem Chem Phys ; 26(11): 8784-8793, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38420852

RESUMO

The homogeneous condensation of water vapor at ambient temperature is studied using molecular dynamics simulation. We reveal that there is a droplet size at the nanoscale where water droplets can be stabilized in the condensation process. Our simulations show that the growth of water droplets is dominated by collision and coagulation between small water droplets after nucleation. This process is found to be accompanied by exceptionally fast evaporation such that droplet growth is balanced by evaporation when water droplets grow to a critical size, approximately 12.5 Å in radius, reaching a stable size distribution. The extremely high evaporation rate is attributed to the curvature dependence of surface tension. Surface tension shows a significant decrease with decreasing droplet size below 20 Å, which causes the total free energy of nanoscaled water droplets to rise after collision and coagulation. Consequently, water droplets have to shrink via fast evaporation. The curvature dependence of surface tension is related to the dielectric ordering of water molecules near the surface of water droplets. Owing to fast evaporation, secondary condensation occurs, and many small water clusters form, ultimately exhibiting a bimodal distribution of water-droplet size.

5.
Cell ; 187(1): 184-203.e28, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38181741

RESUMO

We performed comprehensive proteogenomic characterization of small cell lung cancer (SCLC) using paired tumors and adjacent lung tissues from 112 treatment-naive patients who underwent surgical resection. Integrated multi-omics analysis illustrated cancer biology downstream of genetic aberrations and highlighted oncogenic roles of FAT1 mutation, RB1 deletion, and chromosome 5q loss. Two prognostic biomarkers, HMGB3 and CASP10, were identified. Overexpression of HMGB3 promoted SCLC cell migration via transcriptional regulation of cell junction-related genes. Immune landscape characterization revealed an association between ZFHX3 mutation and high immune infiltration and underscored a potential immunosuppressive role of elevated DNA damage response activity via inhibition of the cGAS-STING pathway. Multi-omics clustering identified four subtypes with subtype-specific therapeutic vulnerabilities. Cell line and patient-derived xenograft-based drug tests validated the specific therapeutic responses predicted by multi-omics subtyping. This study provides a valuable resource as well as insights to better understand SCLC biology and improve clinical practice.


Assuntos
Neoplasias Pulmonares , Proteogenômica , Carcinoma de Pequenas Células do Pulmão , Humanos , Linhagem Celular , Neoplasias Pulmonares/química , Neoplasias Pulmonares/genética , Carcinoma de Pequenas Células do Pulmão/química , Carcinoma de Pequenas Células do Pulmão/genética , Xenoenxertos , Biomarcadores Tumorais/análise
7.
Environ Monit Assess ; 195(12): 1423, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37934331

RESUMO

Industrial wastewater from drug production is one of the contributors to water pollution. For drug wastewater treatment, photodegradation-based chemical technology has gained more attention because of the drug's microbicidal nature and stability. A zinc-chromium-nickel trimetallic-layered double hydroxide compounding with graphene oxide catalyst (ZnCrNi/GO) was synthesized and exhibited a clustered crumb sheet morphology. The prepared catalyst was characterized by a scanning electron microscope (SEM) equipped with an energy-dispersive X-ray spectrometer (EDS), Fourier transform infrared (FTIR) spectra, and X-ray photoelectron spectroscopy (XPS). The results of material analysis established the crystallographic structures of catalysts and evidenced the successful synthesis. The ZnCrNi/GO nanohybrid revealed a higher activity of approximately 90% degradation of tolysin under high-pressure mercury lamp irradiation. The optimized condition of the catalyst dosage of 500 mg/L and the natural pH of the solution at 7.0 under the tylosin concentration of 10 mg/L with high photocatalytic efficiency was explored. In addition, the main reactive species involved in this photocatalysis degradation were explored as the active cavity h+ and ·O2- to a certain extent by the radical trapping experiments. Reuse experiments have shown that as-prepared catalysts possessed the properties of high efficiency and long-lasting catalytic performance, which could meet pharmaceutical wastewater treatment. A three-metal-layered double hydroxide composed by the metal of Ni, Zn, and Cr was synthesized and attached onto graphene oxide. The catalytic materials obtained in this way have a significant catalysis efficiency to tylosin with the likely degradation mechanism of the active cavity h+ and the oxidative capacity of hydroxyl radials.


Assuntos
Monitoramento Ambiental , Tilosina , Hidróxidos
8.
Small ; : e2306237, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38009589

RESUMO

Manganese-based materials are regarded as the most prospective cathode materials because of their high natural abundance, low toxicity, and high specific capacity. Nevertheless, the low conductivity, poor cycling performance, and controversial energy storage mechanisms hinder their practical application. Here, the MnS0.5 Se0.5 microspheres are synthesized by a two-step hydrothermal approach and employed as cathode materials for aqueous zinc-ion batteries (AZIBs) for the first time. Interestingly, in-depth ex situ tests and electrochemical kinetic analyses reveal that MnS0.5 Se0.5 is first irreversibly converted into low-crystallinity ZnMnO3 and MnOx by in situ electrooxidation (MnS0.5 Se0.5 -EOP) during the first charging process, and then a reversible co-insertion/extraction of H+ /Zn2+ occurs in the as-obtained MnS0.5 Se0.5 -EOP electrode during the subsequent discharging and charging processes. Benefiting from the increased surface area, shortened ion transport path, and stable lamellar microsphere structure, the MnS0.5 Se0.5 -EOP electrodes deliver high reversible capacity (272.8 mAh g-1 at 0.1 A g-1 ), excellent rate capability (91.8 mAh g-1 at 2 A g-1 ), and satisfactory cyclic stability (82.1% capacity retention after 500 cycles at 1 A g-1 ). This study not only provides a powerful impetus for developing new types of manganese-based chalcogenides, but also puts forward a novel perspective for exploring the intrinsic mechanisms of in situ electrooxidation behavior.

9.
Sci Rep ; 13(1): 12657, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37542076

RESUMO

The neutron capture cross section of [Formula: see text]Ta is relevant to s-process of nuclear astrophysics, extraterrestrial samples analysis in planetary geology and new generation nuclear energy system design. The [Formula: see text]Ta([Formula: see text]) cross section had been measured between 1 eV and 800 keV at the back-streaming white neutron facility (Back-n) of China spallation neutron source(CSNS) using the time-of-flight (TOF) technique and [Formula: see text] liquid scintillator detectors. The experimental results are compared with the data of several evaluated libraries and previous experiments in the resolved and unresolved resonance region. Resonance parameters are extracted using the R-Matrix code SAMMY in the 1-700 eV region. The astrophysical Maxwell average cross section(MACS) from kT = 5 to 100 keV is calculated over a sufficiently wide range of neutron energies. For the characteristic thermal energy of an astrophysical site, at kT = 30keV the MACS value of [Formula: see text]Ta is 834 ± 75 mb, which shows an obvious discrepancy with the Karlsruhe Astrophysical Database of Nucleosynthesis in Stars (KADoNiS) recommended value 766 ± 15 mb. The new measurements strongly constrain the MACS of [Formula: see text]Ta([Formula: see text]) reaction in the stellar s-process temperatures.

10.
World J Clin Cases ; 11(10): 2308-2314, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37122521

RESUMO

BACKGROUND: Conservative treatments have been reported to diminish or resolve clinical symptoms of lumbar intervertebral disc herniation (LIDH) within a few weeks. CASE SUMMARY: Computed tomography and magnetic resonance imaging (MRI) of the lumbar region of a 25-year-old male diagnosed with LIDH showed prolapse of the L5/S2 disc. The disc extended 1.0 cm beyond the vertebral edge and hung along the posterior vertebral edge. The patient elected a conservative treatment regimen that included traditional Chinese medicine (TCM), acupuncture, and massage. During a follow-up period of more than 12 mo, good improvement in pain was reported without complications. MRI of the lumbar region after 12 mo showed obvious reabsorption of the herniation. CONCLUSION: A conservative treatment regimen of TCM, acupuncture, and massage promoted reabsorption of a prolapsed disc.

11.
Acta Biochim Biophys Sin (Shanghai) ; 55(6): 948-955, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37249335

RESUMO

Small cell lung cancer (SCLC) accounts for approximately 15% of all lung cancer cases and features a strong predilection for early metastasis and extremely poor prognosis. Despite being highly sensitive to chemotherapy and/or radiotherapy initially, most SCLC patients develop therapeutic resistance within one year and die of distant metastases. Multiple studies have revealed the high heterogeneity and strong plasticity of SCLC associated with frequent metastases and early development of therapeutic resistance as well as poor clinical outcome. Importantly, different SCLC subtypes are associated with different therapeutic vulnerabilities, and the inflamed subtype tends to have the best response to immunotherapy, which highlights the importance of precision medicine in the clinic. Here, we review recent advances in SCLC heterogeneity and plasticity and their link to distant metastases and chemotherapy resistance. We hope that a better understanding of the molecular mechanisms underlying SCLC malignant progression will help to develop better intervention strategies for this deadly disease.


Assuntos
Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/patologia , Neoplasias Pulmonares/patologia
12.
Cell Stress Chaperones ; 28(2): 133-144, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36652120

RESUMO

Mitochondria are dynamic organelles that alter their morphology through fission (fragmentation) and fusion (elongation). These morphological changes correlate highly with mitochondrial functional adaptations to stressors, such as hypoxia, pressure overload, and inflammation, and are important in the setting of heart failure. Pathological mitochondrial remodeling, characterized by increased fission and reduced fusion, is associated with impaired mitochondrial respiration, increased mitochondrial oxidative stress, abnormal cytoplasmic calcium handling, and increased cardiomyocyte apoptosis. Considering the impact of the mitochondrial morphology on mitochondrial behavior and cardiomyocyte performance, altered mitochondrial dynamics could be expected to induce or exacerbate the pathogenesis and progression of heart failure. However, whether alterations in mitochondrial fission and fusion accelerate or retard the progression of heart failure has been the subject of intense debate. In this review, we first describe the physiological processes and regulatory mechanisms of mitochondrial fission and fusion. Then, we extensively discuss the pathological contributions of mitochondrial fission and fusion to heart failure. Lastly, we examine potential therapeutic approaches targeting mitochondrial fission/fusion to treat patients with heart failure.


Assuntos
Insuficiência Cardíaca , Dinâmica Mitocondrial , Humanos , Dinâmica Mitocondrial/fisiologia , Mitocôndrias/patologia , Apoptose , Proteínas Mitocondriais
13.
Mol Ecol Resour ; 23(1): 253-272, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35932461

RESUMO

Locoweeds are perennial forbs poisonous to livestock and cause extreme losses to animal husbandry. Locoweed toxicity is attributed to the symbiotic endophytes in Alternaria sect. Undifilum, which produce a mycotoxin swainsonine (SW). We performed a de novo whole genome sequencing of the most common locoweed in China, Oxytropis ochrocephala (2n = 16), and assembled a high-quality, chromosome-level reference genome. Its genome size is 958.83 Mb with 930.94 Mb (97.09%) anchored and oriented onto eight chromosomes, and 31,700 protein-coding genes were annotated. Phylogenetic and collinearity analysis showed it is closely related to Medicago truncatula with a pair of large interchromosomal rearrangements, and both species underwent a whole-genome duplication event. We also derived the genome of A. oxytropis at 74.48 Mb with a contig N50 of 8.87 Mb and 10,657 protein-coding genes, and refined the genes of SW biosynthesis. Multiple Alternaria species containing the swnK gene were grouped into a single clade, but in other genera, swnK's homologues are diverse. Resequencing of 41 A. oxytropis strains revealed one SNP in the SWN cluster causing changes in SW concentration. Comparing the transcriptomes of symbiotic and nonsymbiotic interactions identified differentially expressed genes (DEGs) linked to defence and secondary metabolism in the host. Within the endophyte DEGs were linked to cell wall degradation, fatty acids and nitrogen metabolism. Symbiosis induced the upregulation of most of the SW biosynthetic genes. These two genomes and relevant sequencing data should provide valuable genetic resources for the study of the evolution, interaction, and SW biosynthesis in the symbiont.


Assuntos
Ascomicetos , Oxytropis , Swainsonina/análise , Swainsonina/metabolismo , Oxytropis/genética , Oxytropis/metabolismo , Endófitos/genética , Endófitos/metabolismo , Alternaria/genética , Alternaria/metabolismo , Simbiose/genética , Filogenia , Ascomicetos/metabolismo
14.
Cancer Cell ; 41(1): 88-105.e8, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36525973

RESUMO

Lung squamous cell carcinoma (LUSC) represents a major subtype of lung cancer with limited treatment options. KMT2D is one of the most frequently mutated genes in LUSC (>20%), and yet its role in LUSC oncogenesis remains unknown. Here, we identify KMT2D as a key regulator of LUSC tumorigenesis wherein Kmt2d deletion transforms lung basal cell organoids to LUSC. Kmt2d loss increases activation of receptor tyrosine kinases (RTKs), EGFR and ERBB2, partly through reprogramming the chromatin landscape to repress the expression of protein tyrosine phosphatases. These events provoke a robust elevation in the oncogenic RTK-RAS signaling. Combining SHP2 inhibitor SHP099 and pan-ERBB inhibitor afatinib inhibits lung tumor growth in Kmt2d-deficient LUSC murine models and in patient-derived xenografts (PDXs) harboring KMT2D mutations. Our study identifies KMT2D as a pivotal epigenetic modulator for LUSC oncogenesis and suggests that KMT2D loss renders LUSC therapeutically vulnerable to RTK-RAS inhibition.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Animais , Humanos , Camundongos , Carcinogênese/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/genética , Transformação Celular Neoplásica , Pulmão/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Proteínas ras/antagonistas & inibidores , Proteínas ras/metabolismo
15.
Funct Integr Genomics ; 23(1): 24, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36576616

RESUMO

Colorectal cancer (CRC) is one of the most common malignancies worldwide; however, the potentially possible molecular biological mechanism of CRC is still not completely comprehended. This study aimed to confirm candidate key hub genes involved in the growth and development of CRC and their connection with immune infiltration as well as the related pathways. Gene expression data were selected from the GEO dataset. Hub genes for CRC were identified on the basis of differential expression analysis, weighted gene co-expression network analysis (WGCNA), and LASSO regression. Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and Gene Set Enrichment Analysis (GSEA) were applied to reveal possible functions of the differential genes. Single-sample GSEA (ssGSEA) was implemented to identify the relationship between immune cells infiltration and hub genes. Two hundred and sixty-two differentially expressed genes (DEGs) were identified. Three modules were acquired based on WGCNA, and the blue module presented the highest relevance with CRC. Ten hub genes (AQP8, B3GALT5, CDH3, CEMIP, CPM, FOXQ1, PLAC8, SCNN1B, SPINK5, and SST) were acquired with LASSO analysis as underlying biomarkers for CRC. Compared with normal tissues, CRC tissues presented significantly higher numbers of CD4 T cells, CD8 T cells, B cells, natural regulatory T (Treg) cells, and monocytes. The functional enrichment analyses demonstrated that hub genes were primarily enriched in metabolic process, inflammatory-related, and immune-related response. Ten hub genes were identified to be involved in the occurrence and development of CRC and may be deemed as novel biomarkers for clinical diagnosis and treatment.


Assuntos
Neoplasias Colorretais , Perfilação da Expressão Gênica , Humanos , Biomarcadores , Ontologia Genética , Aprendizado de Máquina , Neoplasias Colorretais/genética , Redes Reguladoras de Genes , Fatores de Transcrição Forkhead , Proteínas
16.
J Chem Phys ; 157(21): 214703, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36511537

RESUMO

The rotational dynamics of water near the ice/water interface and its relation with the crystal growth of ice are investigated by using molecular dynamics simulations. We find that the dipole-moment profiles of water adjacent to interfaces display an oscillation behavior, which is in contrast to the monotonic decay near the free surface for water films. This dielectric oscillation phenomenon is associated with the strong response to hard solid/water interface. It significantly suppresses the dielectric relaxation and slows down the rotational diffusion near the interface compared to bulk water. We propose that the rotational diffusion determines the active degree of growth sites on interfaces, and its slowdown due to the interfacial dielectric oscillation contributes to reducing the growth rate of ice. With this idea, we predict the crystal growth rate of ice based on the modified Wilson-Frenkel model involving rotational dynamics. The theoretical result agrees well with the simulation.

17.
Int J Mol Sci ; 23(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36499701

RESUMO

Brassinolide (BR) is the "sixth class" plant hormone, which plays an important role in various physiological and biochemical processes of plants. The wide variety of functions of Pinellia ternata means that there is huge demand for it and thus it is in short supply. This paper mainly assessed the changes of yield and quality in P. ternata at different stages after BR treatments by principal component analysis, in order to improve the yield and quality of P. ternata and at the same time determine the best harvest time. The results showed that the tuber yield of P. ternata was significantly increased by BR treatments at different stages (except for the 15th day). After the 15th, 45th, 60th, 75th, 90th, and 105th day of treatments, the tuber yield of P. ternata reached peak values at 0.10 (0.65 g), 0.50 (1.97 g), 0.50 (1.98 g), 1.00 (2.37 g), 1.00 (2.84 g), and 2.00 mg/L (3.76 g) BR treatment, respectively. The optimal harvest time was the 75th day after 0.10, 0.50, and 1.00 mg/L BR treatments, which not only significantly improved the yield of P. ternata, but also retained high level of total alkaloids in the tubers (20.89, 5.37, and 13.44%) and bulbils (9.74, 20.42, and 13.62%), high total flavone content in the tubers (17.66, 16.26, and 12.74%) and bulbils (52.63, 12.79, and 38.69%), and high ß-sitosterol content in the tubers (25.26, 16.65, and 0.62%) of P. ternata, compared with the control, respectively.


Assuntos
Alcaloides , Pinellia , Pinellia/química , Análise de Componente Principal , Tubérculos/química , Reguladores de Crescimento de Plantas/análise , Alcaloides/análise
18.
Int J Mol Sci ; 23(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36361895

RESUMO

Low temperatures are often used to preserve fruits and vegetables. However, low-temperature storage also causes problems, such as chilling injury, nitrite accumulation, and browning aggravation in plants. This study investigated the effects of brassinolide (BR,1.0 mg L-1) solution soaking, storage temperatures (-2 ± 0.5 °C, 4 ± 0.5 °C, and 20 ± 1 °C), and their combinations on nitrite content, color change, and quality of stored Toona sinensis bud. The results showed that low temperature (LT, 4 ± 0.5 °C) and near freezing-point temperature (NFPT, -2 ± 0.5 °C) storage effectively inhibited the decay of T. sinensis bud compared to room temperature (20 ± 1 °C, the control). The combined treatments of BR with LT or NFPT reduced nitrite content and maintained the color and the contents of vitamin C, carotenoids, saponins, ß-sitosterol, polyphenol, anthocyanin, flavonoids, and alkaloids in T. sinensis bud. BR soaking delayed the occurrence of chilling injury during NFPT storage. Meanwhile, BR soaking enhanced the DPPH radical scavenging activity, ABTS activity, and FRAP content by increasing SOD and POD activity and the contents of proline, soluble, and glutathione, thus decreasing MDA and hydrogen peroxide content and the rate of superoxide radical production in T. sinensis bud during NFPT storage. This study provides a valuable strategy for postharvest T. sinensis bud in LT and NFPT storage. BR soaking extended the shelf life during LT storage and maintained a better appearance and nutritional quality during NFPT storage.


Assuntos
Nitritos , Toona , Temperatura , Nitritos/farmacologia , Congelamento , Frutas/química
19.
Int J Mol Sci ; 23(18)2022 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-36142812

RESUMO

Pinellia ternata (Thunb.) Druce is a traditional medicinal plant containing a variety of alkaloids, which are important active ingredients. Brassinolide (BR) is a plant hormone that regulates plant response to environmental stress and promotes the accumulation of secondary metabolites in plants. However, the regulatory mechanism of BR-induced alkaloid accumulation in P. ternata is not clear. In this study, we investigated the effects of BR and BR biosynthesis inhibitor (propiconazole, Pcz) treatments on alkaloid biosynthesis in the bulbil of P. ternata. The results showed that total alkaloid content and bulbil yield was enhanced by 90.87% and 29.67% under BR treatment, respectively, compared to the control. We identified 818 (476 up-regulated and 342 down-regulated) and 697 (389 up-regulated and 308 down-regulated) DEGs in the BR-treated and Pcz-treated groups, respectively. Through this annotated data and the Kyoto encyclopedia of genes and genomes (KEGG), the expression patterns of unigenes involved in the ephedrine alkaloid, tropane, piperidine, pyridine alkaloid, indole alkaloid, and isoquinoline alkaloid biosynthesis were observed under BR and Pcz treatments. We identified 11, 8, 2, and 13 unigenes in the ephedrine alkaloid, tropane, piperidine, and pyridine alkaloid, indole alkaloid, and isoquinoline alkaloid biosynthesis, respectively. The expression levels of these unigenes were increased by BR treatment and were decreased by Pcz treatment, compared to the control. The results provided molecular insight into the study of the molecular mechanism of BR-promoted alkaloid biosynthesis.


Assuntos
Alcaloides , Pinellia , Alcaloides/metabolismo , Brassinosteroides , Efedrina , Perfilação da Expressão Gênica , Isoquinolinas/metabolismo , Pinellia/genética , Piperidinas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Piridinas/metabolismo , Esteroides Heterocíclicos , Transcriptoma , Tropanos
20.
Front Plant Sci ; 13: 917301, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35958199

RESUMO

Brassinolide (BR) improves the antioxidant capacity of plants under various abiotic stresses. However, it is not clear about the effect of BR on the antioxidant capacity in plants under non-stress conditions. In the present study, the antioxidant defense response of Pinellia ternata was to be assessed by applying BR and propiconazole (Pcz) under non-stress conditions. BR treatment enhanced the flavonoid content, peroxidase, and ascorbate peroxidase (APX) activity by 12.31, 30.62, and 25.08% and led to an increase in 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity by 4.31% and a decrease in malondialdehyde content by 1.04%. Exogenous application of BR improved the expression levels of PAL, CHS, CHI, and DFR genes by 3. 18-, 3. 39-, 2. 21-, and 0.87-fold in flavonoid biosynthesis, PGI, PMI, and GME genes by 6. 60-, 1437. 79-, and 3.11-fold in ascorbic acid (ASA), biosynthesis, and γECs and GSHS genes by 6.08- and 2.61-fold in glutathione (GSH) biosynthesis pathway, and the expression of these genes were inhibited by Pcz treatment. In addition, BR treatment promoted the ASA-GSH cycle by enhancing the expression of APX, DHAR, and MDHAR genes, which were enhanced by 3. 33-, 157. 85-, and 154.91-fold, respectively. These results provided novel insights into the effect of BR on the antioxidant capacity in bulbil of P. ternata under non-stress conditions and useful knowledge of applying BR to enhance the antioxidant capacity of plants.

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