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1.
Small ; 20(14): e2304622, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37988675

RESUMO

With the rapid development of high-power electronic instruments and communication technology, efficient electromagnetic shielding materials with strong absorption of electromagnetic waves and low reflection characteristics have become the focus of the world's attention. This study designs and synthesizes N-doped carbon-coated hollow Fe3O4 nanospheres (Fe3O4@NC) by spraying Ag nanowires (AgNWs) on textiles as conductive networks. Because of the high permeability and hollow structure Fe3O4@NC, electromagnetic wave goes through a unique process of "absorption, reflection, and reabsorption" when it passes through the surface of the composite textile. In X-band (≈8.2-12.4 GHz), the average electromagnetic interference shielding effectiveness (EMI SE) reaches 50.1 dB, while the reflectance shielding efficiency (SER) is only 2.6 dB, and the average reflectance power coefficient (R) is as low as 0.45. The composite fabric has excellent properties and provides an effective strategy for electromagnetic interference shielding based on absorption.

2.
New Phytol ; 242(6): 2702-2718, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38515244

RESUMO

Hydrolyzable tannins (HTs), predominant polyphenols in oaks, are widely used in grape wine aging, feed additives, and human healthcare. However, the limited availability of a high-quality reference genome of oaks greatly hampered the recognition of the mechanism of HT biosynthesis. Here, high-quality reference genomes of three Asian oak species (Quercus variabilis, Quercus aliena, and Quercus dentata) that have different HT contents were generated. Multi-omics studies were carried out to identify key genes regulating HT biosynthesis. In vitro enzyme activity assay was also conducted. Dual-luciferase and yeast one-hybrid assays were used to reveal the transcriptional regulation. Our results revealed that ß-glucogallin was a biochemical marker for HT production in the cupules of the three Asian oaks. UGT84A13 was confirmed as the key enzyme for ß-glucogallin biosynthesis. The differential expression of UGT84A13, rather than enzyme activity, was the main reason for different ß-glucogallin and HT accumulation. Notably, sequence variations in UGT84A13 promoters led to different trans-activating activities of WRKY32/59, explaining the different expression patterns of UGT84A13 among the three species. Our findings provide three high-quality new reference genomes for oak trees and give new insights into different transcriptional regulation for understanding ß-glucogallin and HT biosynthesis in closely related oak species.


Assuntos
Regulação da Expressão Gênica de Plantas , Genoma de Planta , Genômica , Taninos Hidrolisáveis , Quercus , Quercus/genética , Quercus/metabolismo , Taninos Hidrolisáveis/metabolismo , Genômica/métodos , Regiões Promotoras Genéticas/genética , Especificidade da Espécie , Biomarcadores/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genes de Plantas
3.
Exp Eye Res ; 238: 109743, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38056550

RESUMO

Pigment epithelium-derived factor (PEDF) is widely recognized as a neuroprotective factor expressed in the retina and has shown therapeutic potential in several retinal diseases. Our study aimed to identify the neuroprotective fragment in PEDF and investigate its protective activity in retinas under ischemia-reperfusion (IR) condition. We synthesized a series of shorter synthetic peptides, 6-mer (Ser93-Gln98) and its d-form variant (6 dS) derived from the 44-mer (Val78-Thr121; a PEDF neurotrophic fragment), to determine their cytoprotective activity in IR injury, which was induced in rat retinas by injection of saline into the anterior chamber to increase the intraocular pressure (IOP) followed by reperfusion. We found the cytoprotective effect of 6-mer on glutamate-treated Neuro-2a cells and tert-butyl hydroperoxide (tBHP)-treated 661W cells were 2.6-fold and 1.5-fold higher than the 44-mer, respectively. The cytoprotective effect was blocked by a chemical inhibitor atglistatin and blocking antibody targeting PEDF receptor (PEDF-R). IR induced several impairments in retina, including cell apoptosis, activation of microglia/macroglia, degeneration of retinal capillaries, reduction in electroretinography (ERG) amplitudes, and retinal atrophy. Such IR injuries were ameliorated by treatment with 6-mer and 6 dS eye drops. Also, the neuroprotective activity of 6-mer and 6 dS in ischemic retinas were dramatically reversed by atglistatin preconditioning. Taken together, our data demonstrate smallest neuroprotective fragment of PEDF has potential to treat retinal degeneration-related diseases.


Assuntos
Proteínas do Olho , Fatores de Crescimento Neural , Traumatismo por Reperfusão , Retina , Retinite , Serpinas , Animais , Ratos , Coelhos , Fatores de Crescimento Neural/administração & dosagem , Fatores de Crescimento Neural/química , Fatores de Crescimento Neural/metabolismo , Proteínas do Olho/administração & dosagem , Proteínas do Olho/química , Proteínas do Olho/metabolismo , Serpinas/administração & dosagem , Serpinas/química , Serpinas/metabolismo , Retina/metabolismo , Retina/patologia , Traumatismo por Reperfusão/metabolismo , Citoproteção , Apoptose , Neurônios/metabolismo , Retinite/tratamento farmacológico , Retinite/metabolismo , Administração Tópica , Peptídeos/administração & dosagem , Peptídeos/metabolismo
4.
Inorg Chem ; 63(15): 6714-6722, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38557020

RESUMO

Converting CO2 into valuable chemicals via sustainable energy sources is indispensable for human development. Photothermal catalysis combines the high selectivity of photocatalysis and the high yield of thermal catalysis, which is promising for CO2 reduction. However, the present photothermal catalysts suffer from low activity due to their poor light absorption ability and fast recombination of photogenerated electrons and holes. Here, a TiO2@Bi2WO6 heterojunction photocatalyst featuring a hierarchical hollow structure was prepared by an in situ growth method. The visible light absorption and photothermal effect of the TiO2@Bi2WO6 photocatalyst is promoted by a hierarchical hollow structure, while the recombination phenomenon is significantly mitigated due to the construction of the heterojunction interface and the existence of excited Bi(3-x)+ sites. Such a catalyst exhibits excellent photothermal performance with a CO yield of 43.7 µmol h-1 g-1, which is 15 and 4.7 times higher than that of pure Bi2WO6 and that of physically mixed TiO2/Bi2WO6, respectively. An in situ study shows that the pathway for the transformation of CO2 into CO over our TiO2@Bi2WO6 proceeds via two important intermediates, including COO- and COOH-. Our work provides a new idea of excited states for the design and synthesis of highly efficient photothermal catalysts for CO2 conversion.

5.
J Nanobiotechnology ; 22(1): 274, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38773614

RESUMO

Small extracellular vesicle-derived microRNAs (sEV-miRNAs) have emerged as promising noninvasive biomarkers for early cancer diagnosis. Herein, we developed a molecular probe based on three-dimensional (3D) multiarmed DNA tetrahedral jumpers (mDNA-Js)-assisted DNAzyme activated by Na+, combined with a disposable paper-based electrode modified with a Zr-MOF-rGO-Au NP nanocomplex (ZrGA) to fabricate a novel biosensor for sEV-miRNAs Assay. Zr-MOF tightly wrapped by rGO was prepared via a one-step method, and it effectively aids electron transfer and maximizes the effective reaction area. In addition, the mechanically rigid, and nanoscale-addressable mDNA-Js assembled from the bottom up ensure the distance and orientation between fixed biological probes as well as avoid probe entanglement, considerably improving the efficiency of molecular hybridization. The fabricated bioplatform achieved the sensitive detection of sEV-miR-21 with a detection limit of 34.6 aM and a dynamic range from100 aM to 0.2 µM. In clinical blood sample tests, the proposed bioplatform showed results highly consistent with those of qRT-PCRs and the signal increased proportionally with the NSCLC staging. The proposed biosensor with a portable wireless USB-type analyzer is promising for the fast, easy, low-cost, and highly sensitive detection of various nucleic acids and their mutation derivatives, making it ideal for POC biosensing.


Assuntos
Técnicas Biossensoriais , Vesículas Extracelulares , Limite de Detecção , Estruturas Metalorgânicas , MicroRNAs , Papel , Estruturas Metalorgânicas/química , Vesículas Extracelulares/química , Humanos , Técnicas Biossensoriais/métodos , DNA Catalítico/química , Grafite/química , Ouro/química , DNA/química , Nanopartículas Metálicas/química , Hibridização de Ácido Nucleico , Técnicas Eletroquímicas/métodos , Eletrodos , Zircônio/química
6.
J Asian Nat Prod Res ; 26(3): 293-301, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37162445

RESUMO

Four new iridoid glycosides (1-4), rehmaglutosides L-O, were isolated from the air-dried roots of Rehmannia glutinosa. Their structures were established from the spectroscopic data obtained and by chemical evidence. The known mellittoside (5) and ajugol (6) were also obtained in the current investigation, and the structure of mellittoside was unequivocally defined using X-ray diffraction data. Compounds 1-6 were tested for their cytotoxicity against five human tumor cell lines and proliferation effects on Lactobacillus Reuteri.


Assuntos
Glicosídeos , Rehmannia , Humanos , Glicosídeos/farmacologia , Glicosídeos/química , Rehmannia/química , Glicosídeos Iridoides/farmacologia
7.
J Asian Nat Prod Res ; 26(2): 280-292, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36877100

RESUMO

Seven new pentasaccharides (1-7), rehmaglupentasaccharides A-G, were isolated from the air-dried roots of Rehmannia glutinosa. Their structures were established from the spectroscopic data obtained and by chemical evidence. The known verbascose (8) and stachyose (9) were also obtained in the current investigation, and the structure of stachyose was unequivocally defined using X-ray diffraction data. Compounds 1-9 were tested for their cytotoxicity against five human tumor cell lines, influence on dopamine receptor activation, and proliferation effects against Lactobacillus reuteri.


Assuntos
Rehmannia , Humanos , Rehmannia/química , Linhagem Celular , Raízes de Plantas/química
8.
Phytother Res ; 37(6): 2262-2279, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36726293

RESUMO

Distal metastases from breast cancer, especially bone metastases, are extremely common in the late stages of the disease and are associated with a poor prognosis. EMT is a biomarker of the early process of bone metastasis, and MMP-9 and MMP-13 are important osteoclastic activators. Previously, we found that meso-Hannokinol (HA) could significantly inhibit EMT and MMP-9 and MMP-13 expressions in breast cancer cells. On this basis, we further explored the role of HA in breast cancer bone metastasis. In vivo, we established a breast cancer bone metastasis model by intracardially injecting breast cancer cells. Intraperitoneal injections of HA significantly reduced breast cancer cell metastasis to the leg bone in mice and osteolytic lesions caused by breast cancer. In vitro, HA inhibited the migration and invasion of breast cancer cells and suppressed the expressions of EMT, MMP-9, MMP-13, and other osteoclastic activators. HA inhibited EMT and MMP-9 by activating the ROS/JNK pathway as demonstrated by siJNK and SP600125 inhibition of JNK phosphorylation and NAC scavenging of ROS accumulation. Moreover, HA promoted bone formation and inhibited bone resorption in vitro. In conclusion, our findings suggest that HA may be an excellent candidate for treating breast cancer bone metastasis.


Assuntos
Neoplasias Ósseas , Osteólise , Animais , Camundongos , Metaloproteinase 9 da Matriz , Espécies Reativas de Oxigênio , Metaloproteinase 13 da Matriz , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Metástase Neoplásica
9.
Int J Mol Sci ; 24(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36675134

RESUMO

Acute myeloid leukemia (AML) with a nucleophosmin 1 (NPM1) mutation is a unique subtype of adult leukemia. Recent studies show that NPM1-mutated AML has high autophagy activity. However, the mechanism for upholding the high autophagic level is still not fully elucidated. In this study, we first identified that tumor protein p53 inducible nuclear protein 2 (TP53INP2) was highly expressed and cytoplasmically localized in NPM1-mutated AML cells. Subsequent data showed that the expression of TP53INP2 was upregulated by fat mass and obesity-associated protein (FTO)-mediated m6A modification. Meanwhile, TP53INP2 was delocalized to the cytoplasm by interacting with NPM1 mutants. Functionally, cytoplasmic TP53INP2 enhanced autophagy activity by promoting the interaction of microtubule-associated protein 1 light chain 3 (LC3) - autophagy-related 7 (ATG7) and further facilitated the survival of leukemia cells. Taken together, our study indicates that TP53INP2 plays an oncogenic role in maintaining the high autophagy activity of NPM1-mutated AML and provides further insight into autophagy-targeted therapy of this leukemia subtype.


Assuntos
Leucemia Mieloide Aguda , Proteínas Nucleares , Adulto , Humanos , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Autofagia/genética , Citoplasma/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Mutação , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Nucleofosmina
10.
Int J Mol Sci ; 24(22)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38003547

RESUMO

piRNAs are a class of small non-coding RNAs that play essential roles in modulating gene expression and abundant biological processes. To decode the piRNA-regulated larval response of western honeybees (Apis mellifera) to Ascosphaera apis infection, the expression pattern of piRNAs in Apis mellifera ligustica larval guts after A. apis inoculation was analyzed based on previously obtained high-quality small RNA-seq datasets, followed by structural characterization, target prediction, regulatory network investigation, and functional dissection. Here, 504, 657, and 587 piRNAs were respectively identified in the 4-, 5-, and 6-day-old larval guts after inoculation with A. apis, with 411 ones shared. These piRNAs shared a similar length distribution and first base bias with mammal piRNAs. Additionally, 96, 103, and 143 DEpiRNAs were detected in the 4-, 5-, and 6-day-old comparison groups. Targets of the DEpiRNAs were engaged in diverse pathways such as the phosphatidylinositol signaling system, inositol phosphate metabolism, and Wnt signaling pathway. These targets were involved in three energy metabolism-related pathways, eight development-associated signaling pathways, and seven immune-relevant pathways such as the Jak-STAT signaling pathway. The expression trends of five randomly selected DEpiRNAs were verified using a combination of RT-PCR and RT-qPCR. The effective overexpression and knockdown of piR-ame-945760 in A. apis-infected larval guts were achieved by feeding a specific mimic and inhibitor. Furthermore, piR-ame-945760 negatively regulated the expression of two target immune mRNAs, SOCS5 and ARF1, in the larval gut during the A. apis infection. These findings indicated that the overall expression level of piRNAs was increased and the expression pattern of piRNAs in larval guts was altered due to the A. apis infection, DEpiRNAs were putative regulators in the A. apis-response of A. m. ligustica worker larvae. Our data provide not only a platform for the functional investigation of piRNAs in honeybees, especially in bee larvae, but also a foundation for illuminating the piRNA-involved mechanisms underlying the host response to the A. apis infection.


Assuntos
Onygenales , RNA de Interação com Piwi , Abelhas/genética , Animais , Larva/genética , Larva/metabolismo , Via de Sinalização Wnt , Mamíferos
11.
J Med Virol ; 94(10): 5051-5055, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35729074

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused by the coronavirus severe acute respiratory syndrome coronavirus 2 remains risky worldwide. We elucidate here that good IDM (isolation, disinfection, and maintenance of health) is powerful to reduce COVID-19 deaths based on the striking differences in COVID-19 case fatality rates among various scenarios. IDM means keeping COVID-19 cases away from each other and from other people, disinfecting their living environments, and maintaining their health through good nutrition, rest, and treatment of symptoms and pre-existing diseases (not through specific antiviral therapy). Good IDM could reduce COVID-19 deaths by more than 85% in 2020 and more than 99% in 2022. This is consistent with the fact that good IDM can minimize co-infections and maintain body functions and the fact that COVID-19 has become less pathogenic (this fact was supported with three novel data in this report). Although IDM has been frequently implemented worldwide to some degree, IDM has not been highlighted sufficiently. Good IDM is relative, nonspecific, flexible, and feasible in many countries, and can reduce deaths of some other relatively mild infectious diseases. IDM, vaccines, and antivirals aid each other to reduce COVID-19 deaths. The IDM concept and strategy can aid people to improve their health behavior and fight against COVID-19 and future pandemics worldwide.


Assuntos
Tratamento Farmacológico da COVID-19 , Antivirais/uso terapêutico , Humanos , Pandemias/prevenção & controle , SARS-CoV-2
12.
J Med Virol ; 94(6): 2388-2401, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35072274

RESUMO

The newly established virus family Phenuiviridae in Bunyavirales harbors viruses infecting three kingdoms of host organisms (animals, plants, and fungi), which is rare in known virus families. Many phenuiviruses are arboviruses and replicate in two distinct hosts (e.g., insects and humans or rice). Multiple phenuivirid species, such as Dabie bandavirus, Rift Valley fever phlebovirus, and Rice stripe tenuivirus, are highly pathogenic to humans, animals, or plants. They impose heavy global burdens on human health, livestock industry, and agriculture and are research hotspots. In recent years the taxonomy of Phenuiviridae has been expanded greatly, and research on phenuiviruses has made significant progress. With these advances, this review drew a novel panorama regarding the biomedical significance, distribution, morphology, genomics, taxonomy, evolution, replication, transmission, pathogenesis, and control of phenuiviruses, to aid researchers in various fields to recognize this highly adaptive and important virus family and conduct relevant risk analysis.


Assuntos
Arbovírus , Phlebovirus , Vírus de RNA , Animais , Genômica , Humanos
13.
Inflamm Res ; 71(10-11): 1375-1388, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36109396

RESUMO

OBJECTIVE: The excessive proliferation of fibroblast-like synoviocytes (FLSs) is a key inducement for the occurrence and development of rheumatoid arthritis (RA). Hypoxia inducible factor-α (HIF-α) accumulation is involved in the regulation of cell biological functions in the hypoxic microenvironment of synovium. This study aimed to investigate the roles of HIF-α and its level regulator prolyl hydroxylases (PHDs) in FLSs proliferation and to explore the regulatory effect of geniposide (GE). MATERIALS AND METHODS: Adjuvant arthritis rats and RA-FLSs cell line MH7A were taken as the research objects. MH7A cells were incubated in a hypoxic chamber with 2% O2 for hypoxia treatment. CCK-8, FACS, EdU and Western blot assays were performed to evaluate MH7A cells proliferation. Iron assay was conducted to determine intracellular Fe2+ level. RESULTS: MH7A cells proliferation was significantly enhanced under hypoxia, accompanied by an increase of HIF-1α level. Decreased HIF-1α level by PX-478 inhibited MH7A cells proliferation. Furthermore, PHD2 was highly expressed in vivo and in vitro, and played a key role in modulation of HIF-1α protein level, which was confirmed by PHD2 inhibitor IOX4 and proteasome inhibitor MG132. GE treatment alleviated synovial hyperplasia in AA rats and inhibited MH7A cells proliferation with a reduction in HIF-1α level. Fe2+ acts as an enzymatic cofactor to control PHD2 activity. Iron assay showed that GE reversed the decline of Fe2+ level in MH7A cells under hypoxia. CONCLUSION: GE attenuates abnormal proliferation of RA-FLSs via inhibiting HIF-1α accumulation through enhancement of PHD2 activity.


Assuntos
Artrite Reumatoide , Sinoviócitos , Ratos , Animais , Sinoviócitos/metabolismo , Células Cultivadas , Membrana Sinovial/metabolismo , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Fibroblastos/metabolismo , Hipóxia/metabolismo , Proliferação de Células , Ferro/metabolismo , Ferro/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo
14.
Chem Rev ; 120(20): 11194-11294, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-32915551

RESUMO

Hierarchical zeolites combine the intrinsic catalytic properties of microporous zeolites and the enhanced access and transport of the additional meso- and/or macroporous system. These materials are the most desirable catalysts and sorbents for industry and become a highly evolving field of important current interests. In addition to the enhanced mass transfer leading to high activity, selectivity, and cycle time, another essential merit of the hierarchical structure in zeolite materials is that it can significantly improve the utilization effectiveness of zeolite materials resulting in the minimum energy, time, and raw materials consumption. Substantial progress has been made in the synthesis, characterization, and application of hierarchical zeolites. Herein, we provide an overview of recent achievements in the field, highlighting the significant progress in the past decade on the development of novel and remarkable strategies to create an additional pore system in zeolites. The most innovative synthesis approaches are reviewed according to the principle, versatility, effectiveness, and degree of reality while establishing a firm link between the preparation route and the resultant hierarchical pore quality in zeolites. Zeolites with different hierarchically porous structures, i.e., micro-mesoporous structure, micro-macroporous structure, and micro-meso-macroporous structure, are then analyzed in detail with concrete examples to illustrate their benefits and their fabrications. The significantly improved performances in catalytic, environmental, and biological applications resulting from enhanced mass transport properties are discussed through a series of representative cases. In the concluding part, we envision the emergence of "material-properties-by-quantitative and real rational design" based on the "generalized Murray's Law" that enables the predictable and controlled productions of bioinspired hierarchically structured zeolites. This Review is expected to attract important interests from catalysis, separation, environment, advanced materials, and chemical engineering fields as well as biomedicine for artificial organ and drug delivery systems.


Assuntos
Dióxido de Carbono/isolamento & purificação , Desenho de Fármacos , Compostos Orgânicos Voláteis/isolamento & purificação , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Zeolitas/síntese química , Adsorção , Dióxido de Carbono/química , Tamanho da Partícula , Porosidade , Compostos Orgânicos Voláteis/química , Poluentes Químicos da Água/química , Zeolitas/química
15.
Risk Anal ; 42(5): 1124-1135, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35286734

RESUMO

Infrastructure damage has household-level consequences after a major disaster. Losses are experienced due to factors such as unavailable services and impaired mobility. Socially vulnerable residents, in particular, have few resources with which to adapt. Decision support tools for making justifiable, transparent, repeatable decisions that center the needs of users during recovery are currently nonexistent. In part, this is because infrastructure recovery is a complex process, often involving the coordination of multiple entities. The recovery problem can be rendered more tractable by applying tools suitable for modeling complex systems and processes. System theoretic process analysis (STPA) can be used for goalsetting in a complex, dynamic system such as community civil infrastructure. STPA is used here to devise a decision support tool architecture suitable for coordinated multiagency recovery efforts. The example application is a long-term recovery process with widespread infrastructure damage, population displacement, and other disruptions in system use due to a major disaster. In the example, losses and hazards are defined to reflect recovery challenges commonly faced by vulnerable populations experiencing partial or total displacement. This extension of STPA then reverses these hazards, starting with the most hazardous system states and progressing sequentially to less hazardous states until recovery is complete.


Assuntos
Desastres , Populações Vulneráveis , Tomada de Decisões , Humanos , Análise de Sistemas
16.
Int J Mol Sci ; 23(13)2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35805917

RESUMO

Due to their sessile state, plants are inevitably affected by and respond to the external environment. So far, plants have developed multiple adaptation and regulation strategies to abiotic stresses. One such system is epigenetic regulation, among which DNA methylation is one of the earliest and most studied regulatory mechanisms, which can regulate genome functioning and induce plant resistance and adaption to abiotic stresses. In this review, we outline the most recent findings on plant DNA methylation responses to drought, high temperature, cold, salt, and heavy metal stresses. In addition, we discuss stress memory regulated by DNA methylation, both in a transient way and the long-term memory that could pass to next generations. To sum up, the present review furnishes an updated account of DNA methylation in plant responses and adaptations to abiotic stresses.


Assuntos
Metilação de DNA , Regulação da Expressão Gênica de Plantas , Epigênese Genética , Plantas/genética , Estresse Fisiológico/genética
17.
Int J Mol Sci ; 24(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36613856

RESUMO

The aim was to assess the protective effect of pioglitazone (PGZ) on retinal ganglion cells (RGCs) after anterior ischemic optic neuropathy (AION) in diabetic and non-diabetic mice. Adult C57BL/6 mice with induced diabetes were divided into three groups: group 1: oral PGZ (20 mg/kg) in 0.1% dimethyl sulfoxide (DMSO) for 4 weeks; group 2: oral PGZ (10 mg/kg) in 0.1% DMSO for 4 weeks; and group 3: oral DMSO only for 4 weeks (control group). Two weeks after treatment, AION was induced through photochemical thrombosis. For non-diabetic mice, adult C57BL/6 mice were divided into four groups after AION was induced: group 1: oral DMSO for 4 weeks; group 2: oral PGZ (20 mg/kg) in 0.1% DMSO for 4 weeks; group 3: oral PGZ (20 mg/kg) in 0.1% DMSO + peritoneal injection of GW9662 (one kind of PPAR-γ inhibitor) (1 mg/kg) for 4 weeks; group 4: peritoneal injection of GW9662 (1 mg/kg) for 4 weeks; One week after the induction of AION in diabetic mice, apoptosis in RGCs was much lower in group 1 (8.0 ± 4.9 cells/field) than in group 2 (24.0 ± 11.5 cells/field) and 3 (25.0 ± 7.7 cells/field). Furthermore, microglial cell infiltration in the retina (group 1: 2.0 ± 2.6 cells/field; group 2: 15.6 ± 3.5 cells/field; and group 3: 14.8 ± 7.5 cells/field) and retinal thinning (group 1: 6.7 ± 5.7 µm; group 2: 12.8 ± 6.1 µm; and group 3: 15.8 ± 5.8 µm) were also lower in group 1 than in the other two groups. In non-diabetic mice, preserved Brn3A+ cells were significantly greater in group 2 (2382 ± 140 Brn3A+ cells/mm2, n = 7) than in group 1 (1920 ± 228 Brn3A+ cells/mm2; p = 0.03, n = 4), group 3 (1938 ± 213 Brn3A+ cells/mm2; p = 0.002, n = 4), and group 4 (2138 ± 126 Brn3A+ cells/mm2; p = 0.03, n = 4), respectively; PGZ confers protection to RGCs from damage caused by ischemic optic neuropathy in diabetic and non-diabetic mice.


Assuntos
Disco Óptico , Neuropatia Óptica Isquêmica , Camundongos , Animais , Células Ganglionares da Retina , Neuropatia Óptica Isquêmica/tratamento farmacológico , Pioglitazona/farmacologia , Dimetil Sulfóxido , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
18.
Mol Pharm ; 18(7): 2586-2599, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34102842

RESUMO

Increasing evidence has shown that nanocarriers have effects on several efflux drug transporters. To date, little is known about whether influx transporters are also modulated. Herein, we investigated the impact of amphiphilic polymer micelles on the uptake function of organic cation transporters (OCTs) and the influence on the pharmacokinetics and pharmacodynamics of metformin, a well-characterized substrate of OCTs. Five types of polymeric micelles (mPEG2k-PCL2k, mPEG2k-PCL3.5k, mPEG2k-PCL5k, mPEG2k-PCL7.5k, and mPEG2k-PCL10k) were prepared to evaluate the inhibition of hOCT1-3-overexpressing Madin-Darby canine kidney cells. The mPEG2k-PCLx micelles played an inhibitory role above the critical micelle concentration. The inhibitory potency could be ranked as mPEG2k-PCL2k > mPEG2k-PCL3.5k > mPEG2k-PCL5k > mPEG2k-PCL7.5k > mPEG2k-PCL10k, which negatively declined with the increase of molecular weight of the hydrophobic segment. The inhibitory effects of polymeric micelles on the hOCT1 isoform were the most pronounced, with the lowest IC50 values ranging from 0.106 to 0.280 mg/mL. The mPEG2k-PCL2k micelles distinctly increased the plasma concentration of metformin and significantly decreased Vss by 35.6% (p < 0.05) after seven consecutive treatments in rats, which was interrelated with the restrained metformin distribution in the liver and kidney. The uptake inhibition of micelles on hepatic and renal rOcts also diminished the glucose-lowering effect of metformin and fasting insulin levels in the oral glucose tolerance test. Consistent with the inhibitory effects, the mRNA and protein levels of rOct1 and rOct2 were decreased in the liver, kidney, and small intestine. The present study demonstrated that mPEG2k-PCLx micelles could inhibit the transport function of OCTs, indicating a potential risk of drug-drug interactions during concomitant medication of nanomedicine with organic cationic drugs.


Assuntos
Glicemia/metabolismo , Metformina/farmacologia , Metformina/farmacocinética , Micelas , Proteínas de Transporte de Cátions Orgânicos/antagonistas & inibidores , Polietilenoglicóis/química , Polímeros/química , Animais , Cães , Hipoglicemiantes/química , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/farmacologia , Células Madin Darby de Rim Canino , Masculino , Metformina/química , Metacrilatos/química , Poliésteres/química , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
19.
Environ Res ; 198: 111176, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33933489

RESUMO

A binary component catalyst consists of single atoms (SAs- Pt and Au) anchored on self-doped TiO2 nanotubes (TNTs), was developed for photocatalytic CO2 reduction. The defects introduced TNTs substrate was stabilized with atomic Pt and Au via strong metal support interactions (MSI), due to which, the covalent interactions facilitated an effective transfer of photo-generated electrons from the defective sites to the SAs, and in turn an enhanced separation of electron-hole pairs and charge-carrier transmission. The Pt-Au/R-TNTs with 0.33 wt% of SA metals, exhibited a maximum of 149 times higher photocatalytic performance than unmodified R-TNT and a total apparent quantum yield (AQY) of 17.9%, in which the yield of CH4 and C2H6 reached to 360.0 and 28.8 µmol g-1 h-1, respectively. The metals loading shifted the oxidation path of H2O from •OH generation into O2 evolution, that inhibited the self-oxidization of the photocatalyst.


Assuntos
Dióxido de Carbono , Nanotubos , Catálise , Titânio
20.
Clin Exp Pharmacol Physiol ; 48(8): 1080-1089, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33495999

RESUMO

Sphingosine 1-phosphate (S1P) exerts its various physiological and pathological effects by interacting with G protein-coupled receptors. In addition, S1P can induce biological dysfunction in fibroblast-like synoviocytes (FLSs) in the development of rheumatoid arthritis (RA). However, the mechanism underlying this S1P-induced dysfunction remains unclear. An imbalance between Gαi and Gαs can affect the level of cAMP, an important regulator of numerous cell functions. Therefore, we studied the effects of S1P receptor (S1PR) 1-, 2-, and 3-associated Gαi/Gαs imbalance on the biological function of rheumatoid arthritis fibroblast-like synoviocyte (MH7A cells). The results showed that blocking S1PR1/3 and Gαi, and activating Gαs, inhibited the proliferation, migration, invasion, and proinflammatory cytokine release of MH7A cells in a S1P-induced inflammation model, whereas suppressing S1PR2 only affected the invasion and the release of proinflammatory cytokines of these cells. Analysis of the expression of S1PR1/2/3 and Gαi/Gαs further showed that S1PR1/2/3 could regulate the Gαi/Gαs balance. Furthermore, our data suggested that the level of cAMP was also affected. Combined, our results showed that impaired S1PR1/2/3 signalling can affect MH7A cells biological function via Gαi/Gαs-cAMP signalling, which can provide a new idea for the treatment of RA.


Assuntos
Artrite Reumatoide , Lisofosfolipídeos , Esfingosina/análogos & derivados , Receptores de Esfingosina-1-Fosfato , Sinoviócitos
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