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1.
Anal Chem ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709576

RESUMO

Cytoarchitectural staining is of great importance in disease diagnosis and cell biology research. This study developed user-friendly multifunctional red-emissive carbon dots (R-CDs) for rapid cell nucleus staining via targeting nuclear proteins. R-CDs, simply prepared by electrochemical treatment of 1,2,4-benzenetriamine, exhibit strong emission at 635 nm when excited at 507 nm. The R-CDs can rapidly stain the nucleus of human SH-SY5Y, HepG2, and HUH-7 cells with a high signal-to-noise ratio owing to fluorescence enhancement after entering the nucleus. Compared to conventional cytosolic dyes such as Hoechst and DAPI, R-CDs are cheaper, more highly dispersed in water, and more stable (requiring no stringent storage conditions). The R-CDs show stable optical properties with insignificant photobleaching over 7 days and salt resistance up to 2 M of NaCl. More importantly, R-CDs, possessing a positive charge, allow rapid staining of live cells (3 min) and dead cells (10 s) in saline. According to kinetic variation, R-CDs can distinguish live cells from dead cells. Staining exhibits high efficiency in onion epidermal cells, Aspergillus niger, Caenorhabditis elegans, and human spermatozoa. The mechanism for efficient staining is based on their fast accumulation in the nucleus due to their small size and positive charge and strong interaction with nuclear proteins at amino acid residues of histidine and arginine, resulting in fluorescence enhancement by dozens of times. The developed R-CDs do not bind to DNA and would not cause genetic damage and will find various safe applications in biological and medical fields.

2.
Pathol Res Pract ; 256: 155270, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38552564

RESUMO

BACKGROUND: Non-small cell lung cancer (NSCLC) is a malignancy with high mortality. Immediate early response 5 like (IER5L) has been found to associate with worse prognosis in colorectal cancer patients. However, its role in the prognosis prediction of NSCLC has remained largely unknown. METHODS: The IER5L expression in NSCLC and normal tissues was analyzed in two public cohorts: TCGA-LUAD-LUSC and GSE159857. Additionally, functional enrichment, survival analysis, CIBERSORT and tumor mutation burden (TMB) were investigated between low- and high-IER5L level groups. The in vitro IER5L mRNA and protein levels were determined using RT-qPCR and western blot, respectively. RESULTS: The data from TCGA-LUAD-LUSC and GSE159857 cohorts showed a high IER5L mRNA expression in NSCLC tissue samples compared to normal controls. The increased expression of IER5L in NSCLC cells were also validated by RT-qPCR and western blot analysis. Additionally, NSCLC patients with high-IER5L level had significantly worse prognosis and IER5L could be used as an independent prognostic factor for NSCLC patients. Meanwhile, patients in the high-IER5L group had higher TMB level. IER5L expression was negatively correlated with the proportion of Monocytes and T cells CD4 memory resting, and was positively related to the proportion of Tregs and M0 macrophages in tumor tissues. Besides, transcription factors TFAP4 and ZNF692 may bind to the promoter region of IER5L, and then modulate IER5L gene transcription, thereby affecting IER5L gene expression. Furthermore, GSEA results showed that IER5L gene was closely related to MAPK, PI3K-Akt, NF-kappaB signaling pathways in NSCLC. CONCLUSION: Collectively, high IER5L expression may be a promising unfavorable prognostic biomarker and therapeutic target for NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Inibidores de Checkpoint Imunológico , Fosfatidilinositol 3-Quinases , Neoplasias Pulmonares/genética , Prognóstico , RNA Mensageiro , Proteínas de Ligação a DNA , Fatores de Transcrição
3.
Trends Biochem Sci ; 49(5): 417-430, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38514273

RESUMO

Ion channels establish the voltage gradient across cellular membranes by providing aqueous pathways for ions to selectively diffuse down their concentration gradients. The selectivity of any given channel for its favored ions has conventionally been viewed as a stable property, and in many cation channels, it is determined by an ion-selectivity filter within the external end of the ion-permeation pathway. In several instances, including voltage-activated K+ (Kv) channels, ATP-activated P2X receptor channels, and transient receptor potential (TRP) channels, the ion-permeation pathways have been proposed to dilate in response to persistent activation, dynamically altering ion permeation. Here, we discuss evidence for dynamic ion selectivity, examples where ion selectivity filters exhibit structural plasticity, and opportunities to fill gaps in our current understanding.


Assuntos
Canais Iônicos , Humanos , Canais Iônicos/metabolismo , Canais Iônicos/química , Cátions/metabolismo , Cátions/química , Animais , Ativação do Canal Iônico
4.
J Agric Food Chem ; 72(9): 4574-4586, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38385335

RESUMO

Extensive research has been conducted on Camellia oleifera Abel., a cultivar predominantly distributed in China, to investigate its phytochemical composition, owning to its potential as an edible oil crop. Pentacyclic triterpene saponins, as essential active constituents, play a significant role in contributing to the pharmacological effects of this cultivar. The saponins derived from C. oleifera (CoS) offer a diverse array of bioactivity benefits, including antineoplastic/bactericidal/inflammatory properties, cardiovascular protection, neuroprotection, as well as hypoglycemic and hypolipidemic effects. This review presents a comprehensive analysis of the isolation and pharmacological properties of CoS. Specially, we attempt to reveal the antitumor structure-activity relationship (SAR) of CoS-derived triterpenoids. The active substitution sites of CoS, namely, C-3, C-15, C-16, C-21, C-22, C-23, and C-28 pentacyclic triterpenoids, make it a unique and highly valuable substance with significant medicinal and culinary applications. As such, CoS can play a critical role in transforming people's lives, providing unique medicinal benefits, and contributing to the advancement of both medicine and cuisine.


Assuntos
Camellia , Saponinas , Triterpenos , Humanos , Triterpenos/química , Camellia/química , Relação Estrutura-Atividade , Sementes/química , Saponinas/farmacologia , Saponinas/química
5.
Int J Mol Sci ; 25(4)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38396654

RESUMO

Light is one of the most important environmental factors for plant growth. In the production process of tung oil tree cultivation, due to the inappropriate growth of shading conditions, the lower branches are often dry and dead, which seriously affects the yield of tung oil trees. However, little is known about the key factors of light-induced tree photomorphogenesis. In this study, a total of 22 VfBBX family members were identified to provide a reference for candidate genes in tung tree seedlings. All members of the VfBBX family have different numbers of highly conserved B-box domains or CCT domains. Phylogenetic evolution clustered the VfBBX genes into four categories, and the highest density of members was on chromosome 6. Interspecific collinearity analysis suggested that there were six pairs of duplicate genes in VfBBX members, but the expression levels of all family members in different growth and development stages of the tung tree were significantly divergent. After different degrees of shading treatment and physiological data determination of tung tree seedlings, the differential expression level and chlorophyll synthesis genes correlation analysis revealed that VfBBX9 was a typical candidate nuclear localization transcription factor that was significantly differentially expressed in light response. This study systematically identified the VfBBX gene family and provided a reference for studying its molecular function, enhanced the theoretical basis for tung tree breeding, and identified excellent varieties.


Assuntos
Aleurites , Aleurites/genética , Aleurites/metabolismo , Filogenia , Melhoramento Vegetal , Regulação da Expressão Gênica de Plantas
6.
Chem Asian J ; 19(4): e202301036, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38230541

RESUMO

Malignant tumors seriously threaten human life and well-being. Emerging Near-infrared II (NIR-II, 1000-1700 nm) phototheranostic nanotechnology integrates diagnostic and treatment modalities, offering merits including improved tissue penetration and enhanced spatiotemporal resolution. This remarkable progress has opened promising avenues for advancing tumor theranostic research. The tumor microenvironment (TME) differs from normal tissues, exhibiting distinct attributes such as hypoxia, acidosis, overexpressed hydrogen peroxide, excess glutathione, and other factors. Capitalizing on these attributes, researchers have developed TME-activatable NIR-II phototheranostic agents with diagnostic and therapeutic attributes concurrently. Therefore, developing TME-activatable NIR-II phototheranostic agents with diagnostic and therapeutic activation holds significant research importance. Currently, research on TME-activatable NIR-II phototheranostic agents is still in its preliminary stages. This review examines the recent advances in developing dual-functional NIR-II activatable phototheranostic agents over the past years. It systematically presents NIR-II phototheranostic agents activated by various TME factors such as acidity (pH), hydrogen peroxide (H2 O2 ), glutathione (GSH), hydrogen sulfide (H2 S), enzymes, and their hybrid. This encompasses NIR-II fluorescence and photoacoustic imaging diagnostics, along with therapeutic modalities, including photothermal, photodynamic, chemodynamic, and gas therapies triggered by these TME factors. Lastly, the difficulties and opportunities confronting NIR-II activatable phototheranostic agents in the simultaneous diagnosis and treatment field are highlighted.


Assuntos
Nanopartículas , Neoplasias , Humanos , Fototerapia/métodos , Nanomedicina Teranóstica/métodos , Microambiente Tumoral , Peróxido de Hidrogênio , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Glutationa , Nanopartículas/uso terapêutico , Linhagem Celular Tumoral
7.
Dalton Trans ; 53(2): 666-674, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38073603

RESUMO

Although antibacterial platforms involving nanozymes have been extensively investigated, there are still problems of poor reactive oxygen species generation efficiency and obstinate bacterial biofilms. Developing a nanozyme-photothermal therapy nanoplatform with superior sterilization effects and minimal side effects would be a good alternative for completely eliminating bacteria and biofilms. Herein, an ultrathin PdMo bimetallene nanozyme with a planar topology and boosted metal utilization, exhibiting excellent photothermal and peroxidase-like activity, is designed for synergistic nanozyme-photothermal sterilization applications and accelerated wound healing. The superior catalytic activity of PdMo bimetallene nanozymes could convert a biosafe concentration of hydrogen peroxide (H2O2) into large quantities of toxic hydroxyl radicals (•OH) under laser irradiation, enhancing bacterial membrane permeability and thermal sensitivity for efficient removal of bacteria and biofilms. In addition, PdMo bimetallene presents a good wound-healing ability according to the results of fibroblast proliferation and collagen deposition with minor side effects. This work would provide an innovative avenue for developing metallene-based nanozymes for biomedical applications.


Assuntos
Peróxido de Hidrogênio , Cicatrização , Peróxido de Hidrogênio/farmacologia , Antibacterianos/farmacologia , Biofilmes , Permeabilidade da Membrana Celular
8.
Adv Healthc Mater ; 13(10): e2303451, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37983596

RESUMO

Chemodynamic therapy (CDT) is a particular oncological therapeutic strategy by generates the highly toxic hydroxyl radical (•OH) from the dismutation of endogenous hydrogen peroxide (H2O2) via Fenton or Fenton-like reactions. However, single CDT therapies have been limited by unsatisfactory efficacy. Enhanced chemodynamic therapy (ECDT) triggered by near-infrared (NIR) is a novel therapeutic modality based on light energy to improve the efficiency of Fenton or Fenton-like reactions. However, the limited penetration and imaging capability of the visible (400-650 nm) and traditional NIR-I region (650-900 nm) light-amplified CDT restrict the prospects for its clinical application. Combined with the high penetration/high precision imaging characteristics of the second near-infrared (NIR-II,) nanoplatform, it is expected to kill deep tumors efficiently while imaging the treatment process in real-time, and more notably, the NIR-II region radiation with wavelengths above 1000 nm can minimize the irradiation damage to normal tissues. Such NIR-II ECDT nanoplatforms have greatly improved the effectiveness of CDT therapy and demonstrated extraordinary potential for clinical applications. Accordingly, various strategies have been explored in the past years to improve the efficiency of NIR-II Enhanced CDT. In this review, the mechanisms and strategies used to improve the performance of NIR-II-enhanced CDT are outlined.


Assuntos
Nanopartículas , Neoplasias , Humanos , Peróxido de Hidrogênio , Fototerapia , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Microambiente Tumoral
9.
Sci Adv ; 9(49): eadj5539, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38064553

RESUMO

Eukaryotic voltage-gated K+ channels have been extensively studied, but the structural bases for some of their most salient functional features remain to be established. C-type inactivation, for example, is an auto-inhibitory mechanism that confers temporal resolution to their signal-firing activity. In a recent breakthrough, studies of a mutant of Shaker that is prone to inactivate indicated that this process entails a dilation of the selectivity filter, the narrowest part of the ion conduction pathway. Here, we report an atomic-resolution cryo-electron microscopy structure that demonstrates that the wild-type channel can also adopt this dilated state. All-atom simulations corroborate this conformation is congruent with the electrophysiological characteristics of the C-type inactivated state, namely, residual K+ conductance and altered ion specificity, and help rationalize why inactivation is accelerated or impeded by certain mutations. In summary, this study establishes the molecular basis for an important self-regulatory mechanism in eukaryotic K+ channels, laying a solid foundation for further studies.


Assuntos
Ativação do Canal Iônico , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Microscopia Crioeletrônica , Dilatação , Ativação do Canal Iônico/fisiologia
10.
J Nanobiotechnology ; 21(1): 489, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38111035

RESUMO

Orthotopic advanced hepatic tumor resection without precise location and preoperative downstaging may cause clinical postoperative recurrence and metastasis. Early accurate monitoring and tumor size reduction based on the multifunctional diagnostic-therapeutic integration platform could improve real-time imaging-guided resection efficacy. Here, a Near-Infrared II/Photoacoustic Imaging/Magnetic Resonance Imaging (NIR-II/PAI/MRI) organic nanoplatform IRFEP-FA-DOTA-Gd (IFDG) is developed for integrated diagnosis and treatment of orthotopic hepatic tumor. The IFDG is designed rationally based on the core "S-D-A-D-S" NIR-II probe IRFEP modified with folic acid (FA) for active tumor targeting and Gd-DOTA agent for MR imaging. The IFDG exhibits several advantages, including efficient tumor tissue accumulation, good tumor margin imaging effect, and excellent photothermal conversion effect. Therefore, the IFDG could realize accurate long-term monitoring and photothermal therapy non-invasively of the hepatic tumor to reduce its size. Next, the complete resection of the hepatic tumor in situ lesions could be realized by the intraoperative real-time NIR-II imaging guidance. Notably, the preoperative downstaging strategy is confirmed to lower the postoperative recurrence rate of the liver cancer patients under middle and advanced stage effectively with fewer side effects. Overall, the designed nanoplatform demonstrates great potential as a diagnostic-therapeutic integration platform for precise imaging-guided surgical navigation of orthotopic hepatic tumors with a low recurrence rate after surgery, providing a paradigm for diagnosing and treating the advanced tumors in the future clinical translation application.


Assuntos
Neoplasias Hepáticas , Nanopartículas , Cirurgia Assistida por Computador , Humanos , Fototerapia , Imageamento por Ressonância Magnética/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Linhagem Celular Tumoral
11.
Anal Chem ; 95(47): 17372-17383, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37963241

RESUMO

The activable NIR-based phototheranostic nanoplatform (NP) is considered an efficient and reliable tumor treatment due to its strong targeting ability, flexible controllability, minimal side effects, and ideal therapeutic effect. This work describes the rational design of a second near-infrared (NIR-II) fluorescence imaging-guided organic phototheranostic NP (FTEP-TBFc NP). The molecular-engineered phototheranostic NP has a sensitive response to glutathione (GSH), generating hydrogen sulfide (H2S) gas, and delivering ferrocene molecules in the tumor microenvironment (TME). Under 808 nm irradiation, FTEP-TBFc could not only simultaneously generate fluorescence, heat, and singlet oxygen but also greatly enhance the generation of reactive oxygen species to improve chemodynamic therapy (CDT) and photodynamic therapy (PDT) at a biosafe laser power of 0.33 W/cm2. H2S inhibits the activity of catalase and cytochrome c oxidase (COX IV) to cause the enhancement of CDT and hypothermal photothermal therapy (HPTT). Moreover, the decreased intracellular GSH concentration further increases CDT's efficacy and downregulates glutathione peroxidase 4 (GPX4) for the accumulation of lipid hydroperoxides, thus causing the ferroptosis process. Collectively, FTEP-TBFc NPs show great potential as a versatile and efficient NP for specific tumor imaging-guided multimodal cancer therapy. This unique strategy provides new perspectives and methods for designing and applying activable biomedical phototheranostics.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Microambiente Tumoral , Fotoquimioterapia/métodos , Terapia Combinada , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Imagem Óptica , Linhagem Celular Tumoral , Nanomedicina Teranóstica/métodos
12.
Adv Sci (Weinh) ; 10(36): e2304104, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37983599

RESUMO

Tumor microenvironment (TME)-triggered phototheranostic platform offers a feasible strategy to improve cancer diagnosis accuracy and minimize treatment side effects. Developing a stable and biocompatible molecular phototheranostic platform for TME-activated second near-infrared (NIR-II) fluorescence imaging-guided multimodal cascade therapy is a promising strategy for creating desirable anticancer agents. Herein, a new NIR-II fluorescence imaging-guided activatable molecular phototheranostic platform (IR-FEP-RGD-S-S-S-Fc) is presented for actively targeted tumor imaging and hydrogen sulfide (H2 S) gas-enhanced chemodynamic-hypothermal photothermal combined therapy (CDT/HPTT). It is revealed for the first time that the coupling distance between IR-FE and ferrocene is proportional to the photoinduced electron transfer (PET), and the aqueous environment is favorable for PET generation. The part of Cyclic-RGDfK (cRGDfk) peptides can target the tumor and benefit the endocytosis of nanoparticles. The high-concentration glutathione (GSH) in the TME will separate the fluorescence molecule and ferrocene by the GSH-sensitive trisulfide bond, realizing light-up NIR-II fluorescence imaging and a cascade of trimodal synergistic CDT/HPTT/gas therapy (GT). In addition, the accumulation of hydroxyl radicals (•OH) and down-regulation of glutathione peroxidase 4 (GPX4) can produce excessive harmful lipid hydroperoxides, ultimately leading to ferroptosis.


Assuntos
Neoplasias , Terapia Fototérmica , Humanos , Metalocenos , Imagem Óptica , Glutationa , Microambiente Tumoral
13.
Nature ; 622(7982): 410-417, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37758949

RESUMO

The Kv2.1 voltage-activated potassium (Kv) channel is a prominent delayed-rectifier Kv channel in the mammalian central nervous system, where its mechanisms of activation and inactivation are critical for regulating intrinsic neuronal excitability1,2. Here we present structures of the Kv2.1 channel in a lipid environment using cryo-electron microscopy to provide a framework for exploring its functional mechanisms and how mutations causing epileptic encephalopathies3-7 alter channel activity. By studying a series of disease-causing mutations, we identified one that illuminates a hydrophobic coupling nexus near the internal end of the pore that is critical for inactivation. Both functional and structural studies reveal that inactivation in Kv2.1 results from dynamic alterations in electromechanical coupling to reposition pore-lining S6 helices and close the internal pore. Consideration of these findings along with available structures for other Kv channels, as well as voltage-activated sodium and calcium channels, suggests that related mechanisms of inactivation are conserved in voltage-activated cation channels and likely to be engaged by widely used therapeutics to achieve state-dependent regulation of channel activity.


Assuntos
Ativação do Canal Iônico , Mutação , Canais de Potássio Shab , Animais , Humanos , Microscopia Crioeletrônica , Interações Hidrofóbicas e Hidrofílicas , Ativação do Canal Iônico/genética , Canais de Potássio Shab/genética , Canais de Potássio Shab/metabolismo , Canais de Potássio Shab/ultraestrutura , Espasmos Infantis/genética
14.
Plants (Basel) ; 12(10)2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37653852

RESUMO

The Camellia oil tree (Camellia oleifera Abel.) is an important nonwood forest species in China, and the majority of its cultivars are late-acting self-incompatibility (LSI) types. Although several studies have examined the mechanism of LSI, the process is quite complicated and unclear. In this study, pollen tube growth and fruit setting of two Camellia oil tree cultivars Huashuo (HS) and Huajin (HJ) were investigated after non and self-pollination, and transcriptomic analysis of the ovaries was performed 48 h after self-pollination to identify the potential genes implicated in the LSI of Camellia oil trees. The results showed that the fruit set of HS was significantly higher than that of HJ after self-pollination. Transcriptomic analysis revealed that plant hormone signal transduction, the phosphatidylinositol signaling system, ATP-binding cassette (ABC) transporters, reactive oxygen species (ROS) metabolism, and Ca2+ signaling were mainly contributed in the LSI of reaction of Camellia oil tree. Moreover, nine RNase T2 genes were identified from the transcriptome analysis, which also showed that CoRNase7 participated in the self-incompatibility reaction in HS. Based on phylogenetic analysis, CoRNase6 was closely related to S-RNase from coffee, and CoRNase7 and CoRNase8 were closely related to S-RNase from Camellia sinensis. The 9 RNase T2 genes successfully produced proteins in prokaryotes. Subcellular localization indicated that CoRNase1 and CoRNase5 were cytoplasmic proteins, while CoRNase7 was a plasma membrane protein. These results screened the main metabolic pathways closely related to LSI in Camellia oil tree, and SI signal transduction might be regulated by a large molecular regulatory network. The discovery of T2 RNases provided evidence that Camellia oil tree might be under RNase-based gametophytic self-incompatibility.

15.
Planta ; 258(3): 65, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37566145

RESUMO

MAIN CONCLUSION: Ectopic expression of Camellia oleifera Abel. gibberellin 20-oxidase 1 caused a taller phenotype, promoted secondary cell wall deposition, leaf enlargement, and early flowering, and reduced chlorophyll and anthocyanin accumulation and seed enlargement phenotype in Arabidopsis. Plant height and secondary cell wall (SCW) deposition are important plant traits. Gibberellins (GAs) play important roles in regulating plant height and SCWs deposition. Gibberellin 20-oxidase (GA20ox) is an important enzyme involved in GA biosynthesis. In the present study, we identified a GA synthesis gene in Camellia oleifera. The total length of the CoGA20ox1 gene sequence was 1146 bp, encoding 381 amino acids. Transgenic plants with CoGA20ox1 had a taller phenotype; a seed enlargement phenotype; promoted SCWs deposition, leaf enlargement, and early flowering; and reduced chlorophyll and anthocyanin accumulation. Genetic analysis showed that the mutant ga20ox1-3 Arabidopsis partially rescued the phenotype of CoGA20ox1 overexpression plants. The results showed that CoGA20ox1 participates in the growth and development of C. oleifera. The morphological changes in CoGA20ox1 overexpressed plants provide a theoretical basis for further exploration of GA biosynthesis and analysis of the molecular mechanism in C. oleifera.


Assuntos
Arabidopsis , Camellia , Arabidopsis/metabolismo , Camellia/genética , Camellia/metabolismo , Antocianinas/metabolismo , Expressão Ectópica do Gene , Giberelinas/metabolismo , Plantas Geneticamente Modificadas/genética , Parede Celular/metabolismo , Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas
16.
Elife ; 122023 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-37199723

RESUMO

The cation-permeable TRPV2 channel is important for cardiac and immune cell function. Cannabidiol (CBD), a non-psychoactive cannabinoid of clinical relevance, is one of the few molecules known to activate TRPV2. Using the patch-clamp technique, we discover that CBD can sensitize current responses of the rat TRPV2 channel to the synthetic agonist 2-aminoethoxydiphenyl borate (2-APB) by over two orders of magnitude, without sensitizing channels to activation by moderate (40°C) heat. Using cryo-EM, we uncover a new small-molecule binding site in the pore domain of rTRPV2 in addition to a nearby CBD site that had already been reported. The TRPV1 and TRPV3 channels are also activated by 2-APB and CBD and share multiple conserved features with TRPV2, but we find that strong sensitization by CBD is only observed in TRPV3, while sensitization for TRPV1 is much weaker. Mutations at non-conserved positions between rTRPV2 and rTRPV1 in either the pore domain or the CBD sites failed to confer strong sensitization by CBD in mutant rTRPV1 channels. Together, our results indicate that CBD-dependent sensitization of rTRPV2 channels engages multiple channel regions, and that the difference in sensitization strength between rTRPV2 and rTRPV1 channels does not originate from amino acid sequence differences at the CBD binding site or the pore domain. The remarkably robust effect of CBD on TRPV2 and TRPV3 channels offers a promising new tool to both understand and overcome one of the major roadblocks in the study of these channels - their resilience to activation.


Assuntos
Canabidiol , Canabinoides , Ratos , Animais , Canabidiol/farmacologia , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo , Temperatura Alta , Mutação
17.
Plant Dis ; 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37018209

RESUMO

Puding County is the major Allium tuberosum growing area in Guizhou Province of China. In 2019, white leaf spots were observed on Allium tuberosum in Puding County (26.31°N, 105.64°E). The white spots, ranging from elliptic to irregular in shape, first appeared on leaf tips. With disease aggravation, spots gradually coalesced, forming necrotic patches with yellow margins causing leaf necrosis; sometimes there was gray mold on dead leaves. The incidence of the diseased leaf rate was estimated to be 27-48%. To identify the pathogenic agent, 150 leaf tissues (5 mm × 5 mm) were obtained from disease-healthy junctions of 50 diseased leaves. Leaf tissues were disinfected in 75% ethanol for 30 s, soaked in 0.5% sodium hypochlorite for 5 min, and flushed three times with sterile water, before being placed on potato dextrose agar (PDA) in the dark at 25 °C. When colonies appeared, the mycelial tips were picked and placed on new PDA. Purified fungus was obtained after repeating this last step several times. The colonies were grayish-green with white round margins. Conidiophores (2.7-4.5 µm × 27-81 µm) were brown, straight, or flexuous with branches and septa. Conidia (8-34 µm × 5-16 µm) were brown, with 0-5 transverse septa and 0-4 longitudinal septa. The 18S nuclear ribosomal DNA (nrDNA; SSU), 28S nrDNA (LSU), RNA polymerase II second largest subunit (RPB2), internal transcribed spacer (ITS), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and translation elongation factor 1-alpha (TEF-α) (Woudenberg et al. 2013) were amplified and sequenced. The sequences were deposited in GenBank (ITS: OP703616, LSU: OP860684, SSU: OP860685, GAPDH: OP902372, RPB2: OP902373, TEF1-α: OP902374). According to BLAST analysis, the ITS, LSU, GAPDH, RPB2, SSU, and TEF1-α of the straishowed 100% (689 of 731 base pairs; bp), 100% (916 of 938 bp), 100% (579 of 600 bp), 100% (946 of 985 bp), 100% (1093 of 1134 bp), and 100% (240 of 240 bp) sequence identity to those of Alternaria alternata (ITS: LC440581.1, LSU: KX609781.1, GAPDH: MT109295.1, RPB2: MK605900.1, SSU: ON055699.1 and TEF1-α: OM220081.1). A phylogenetic tree was constructed using PAUP4 and the maximum parsimony method with 1000 replicas of bootstrapping for all datasets. According to morphological characteristics and phylogenetic analysis, FJ-1 was identified as Alternaria alternata (Simmons 2007, Woudenberg et al. 2015). The strain was preserved in the Agricultural Culture Collection of China (preservation number: ACC39969). To determine the pathogenicity of Alternaria alternata against Allium tuberosum, wounded healthy leaves were inoculated with a conidial suspension (106 conidial/mL) and round mycelial plugs (4mm). Sterile agar PDA plugs with no mycelium or sterile water were inoculated as negative controls. Three days later, white spots appeared on the wounded leaves inoculated with mycelial plugs or conidial suspension. However, the symptoms caused by conidial suspensions were weaker than those caused by mycelial plugs. No symptoms were observed in the control group. The experimental symptoms were consistent with the phenomena observed in the field. The same fungus was reisolated from necrotic lesions and identified as Alternaria alternata using the method described above. To our knowledge, this is the first report of Alternaria alternata causing white leaf spots on Allium tuberosum in China, a disease seriously affected the yield and quality of Allium tuberosum and caused economic losses to farmers. Reference: Simmons EG (2007) Alternaria: an identification manual. CBS Fungal Biodiversity Centre, Utrecht, the Netherlands. Woudenberg JHC, Groenewald JZ, Binder M, Crous PW ( 2013) Alternaria redefined. Stud Mycol, 75: 171-212. https://doi.org/10.3114/sim0015. Woudenberg JHC, Seidl MF, Groenewald JZ, Vries M de, Stielow JB, Thomma BPHJ, Crous PW (2015) Alternaria section Alternaria: Species, formae speciales or pathotypes? Stud Mycol, 82:1-21. https://doi.org/10.1016/j.simyco.2015.07.001.

18.
Front Plant Sci ; 14: 1126660, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36968351

RESUMO

Introduction: The Camellia oleifera (C. oleifera) cultivars 'Huashuo' (HS) and 'Huaxin' (HX) are new high-yielding and economically valuable cultivars that frequently encounter prolonged cold weather during the flowering period, resulting in decreased yields and quality. The flower buds of HS sometimes fail to open or open incompletely under cold stress, whereas the flower buds of HX exhibit delayed opening but the flowers and fruits rarely drop. Methods: In this study, flower buds at the same development stage of two C. oleifera cultivars were used as test materials for a combination of physiological, transcriptomic and metabolomic analyses, to unravel the different cold regulatory mechanisms between two cultivars of C. oleifera. Results and discussion: Key differentially expressed genes (DEGs) and differentially expressed metabolites (DEMs) involved in sugar metabolism, phenylpropanoid biosynthesis, and hormone signal transduction were significantly higher in HX than in HS, which is consistent with phenotypic observations from a previous study. The results indicate that the flower buds of HX are less affected by long-term cold stress than those of HS, and that cold resistance in C. oleifera cultivars varies among tissues or organs.This study will provide a basis for molecular markers and molecular breeding of C. oleifera.

19.
Small ; 19(26): e2207995, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36942859

RESUMO

Effectively interfering energy metabolism in tumor cells and simultaneously activating the in vivo immune system to perform immune attacks are meaningful for tumor treatment. However, precisely targeted therapy is still a huge challenge. Herein, a mitochondrial-targeting phototheranostic system, FE-T nanoparticles (FE-T NPs) are developed to damage mitochondria in tumor cells and change the tumor immunosuppressive microenvironment. FE-T NPs are engineered by encapsulating the near-infrared (NIR) absorbed photosensitizer IR-FE-TPP within amphiphilic copolymer DSPE-SS-PEG-COOH for high-performing with simultaneous mitochondrial-targeting, near-infrared II (NIR-II) fluorescence imaging, and synchronous photothermal therapy (PTT) /photodynamic therapy (PDT) /immune therapy (IMT). In tumor treatment, the disulfide in the copolymer can be cleaved by excess intracellular glutathione (GSH) to release IR-FE-TPP and accumulate in mitochondria. After 808 nm irradiation, the mitochondrial localization of FE-T NPs generated reactive oxygen species (ROS), and hyperthermia, leading to mitochondrial dysfunction, photoinductive apoptosis, and immunogenic cell death (ICD). Notably, in situ enhanced PDT/PTT in vivo via mitochondrial-targeting with FE-T NPs boosts highly efficient ICD toward excellent antitumor immune response. FE-T NPs provide an effective mitochondrial-targeting phototheranostic nanoplatform for imaging-guided tumor therapy.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Terapia Combinada , Fármacos Fotossensibilizantes , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Polímeros , Mitocôndrias , Fotoquimioterapia/métodos , Linhagem Celular Tumoral , Fototerapia/métodos , Microambiente Tumoral
20.
bioRxiv ; 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36747846

RESUMO

The cation-permeable TRPV2 channel is essential for cardiac and immune cells. Cannabidiol (CBD), a non-psychoactive cannabinoid of clinical relevance, is one of the few molecules known to activate TRPV2. Using the patch-clamp technique we discover that CBD can sensitize current responses of the rat TRPV2 channel to the synthetic agonist 2-aminoethoxydiphenyl borate (2- APB) by over two orders of magnitude, without sensitizing channels to activation by moderate (40 °C) heat. Using cryo-EM we uncover a new small-molecule binding site in the pore domain of rTRPV2 that can be occupied by CBD in addition to a nearby CBD site that had already been reported. The TRPV1 and TRPV3 channels share >40% sequence identity with TRPV2 are also activated by 2-APB and CBD, but we only find a strong sensitizing effect of CBD on the response of mouse TRPV3 to 2-APB. Mutations at non-conserved positions between rTRPV2 and rTRPV1 in either the pore domain or the CBD sites failed to confer strong sensitization by CBD in mutant rTRPV1 channels. Together, our results indicate that CBD-dependent sensitization of TRPV2 channels engages multiple channel regions and possibly involves more than one CBD and 2-APB sites. The remarkably robust effect of CBD on TRPV2 and TRPV3 channels offers a promising new tool to both understand and overcome one of the major roadblocks in the study of these channels - their resilience to activation.

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