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1.
Nano Lett ; 23(23): 11233-11242, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-37992235

RESUMO

Rechargeable magnesium batteries (RMBs) have been proposed as a promising alternative to currently commercialized lithium-ion batteries. However, Mg anode passivation in conventional electrolytes necessitates the use of highly corrosive Cl- ions in the electrolyte. Herein for the first time, we design a chloride-free electrolyte for RMBs with magnesium bis(hexamethyldisilazide) (Mg(HMDS)2) and magnesium triflate (Mg(OTf)2) as the main salts and tetrabutylammonium triflate (TBAOTf) as an additive. The TBAOTf additive improved the dissolution of Mg salts, consequently enhancing the charge-carrying species in the electrolyte. COMSOL studies further revealed desirable Mg growth in our modulated electrolyte, substantiated by homogeneous electric flux distribution across the electrolyte-electrode interface. Post-mortem chemical composition analysis uncovered a MgF2-rich solid electrolyte interphase (SEI) that facilitated exceptional Mg deposition/dissolution reversibility. Our study illustrates a highly promising strategy for synthesizing a corrosion-free and reversible Mg battery electrolyte with a widened anodic stability window of up to 4.43 V.

2.
Nat Commun ; 14(1): 5499, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679330

RESUMO

The emergence of caste-differentiated colonies, which have been defined as 'superorganisms', in ants, bees, and wasps represents a major transition in evolution. Lifetime mating commitment by queens, pre-imaginal caste determination and lifetime unmatedness of workers are key features of these animal societies. Workers in superorganismal species like honey bees and many ants have consequently lost, or retain only vestigial spermathecal structures. However, bumble bee workers retain complete spermathecae despite 25-40 million years since their origin of superorganismality, which remains an evolutionary mystery. Here, we show (i) that bumble bee workers retain queen-like reproductive traits, being able to mate and produce colonies, underlain by queen-like gene expression, (ii) the social conditions required for worker mating, and (iii) that these abilities may be selected for by early queen-loss in these annual species. These results challenge the idea of lifetime worker unmatedness in superorganisms, and provide an exciting new tool for the conservation of endangered bumble bee species.


Assuntos
Abelhas , Abelhas/anatomia & histologia , Abelhas/genética , Abelhas/fisiologia , Masculino , Feminino , Animais , Expressão Gênica , Comportamento Sexual Animal , Evolução Biológica
3.
ACS Nano ; 17(19): 19459-19469, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37768556

RESUMO

Low-temperature lithium metal batteries are of vital importance for cold-climate condition applications. Their realization, however, is plagued by the extremely sluggish Li+ transport kinetics in the vicinity of Li metal anode at low temperatures. Different from the widely adopted electrolyte engineering, a functional interphase design concept is proposed in this work to efficiently improve the low-temperature electrochemical reaction kinetics of Li metal anodes. As a proof of concept, we design a hybrid polymer-alloy-fluoride (PAF) interphase featuring numerous gradient fluorinated solid-solution alloy composite nanoparticles embedded in a polymerized dioxolane matrix. Systematic experimental and theoretical investigations demonstrate that the hybrid PAF interphase not only exhibits superior lithiophilicity but also provides abundant ionic conductive pathways for homogeneous and fast Li+ transport at the Li-electrolyte interface. With enhanced interfacial dynamics of Li-ion migration, the as-designed PAF-Li anode works stably for 720 h with low voltage hysteresis and dendrite-free electrode morphology in symmetric cell configurations at -40 °C. The full cells with PAF-Li anode display a commercial-grade capacity of 4.26 mAh cm-2 and high capacity retention of 74.7% after 150 cycles at -20 °C. The rational functional interphase design for accelerating ion-transfer kinetics sheds innovative insights for developing high-areal-capacity and long-lifespan lithium metal batteries at low temperatures.

4.
Nano Lett ; 23(12): 5762-5769, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37310729

RESUMO

Lithium-sulfur batteries (LSBs) are known to be potential next-generation energy storage devices. Recently, our group reported an LSB cathode made using sulfur spheres that has been spherically templated by MXene nanosheets decorated with CoSe2 nanoparticles, forming a "loose-templating" configuration. It was postulated that the minimal restacking of the outer nanoparticle-decorated MXene layer helps to enable facile ionic transport. However, as the nanosheets do not adhere conformally to the internal sphere's surface, such a configuration can be controversial, thus requiring a more systematic understanding. In this work, we report and quantify for the first time the independent and dependent variables involved in this morphology, allowing us to identify that having smaller nanoparticles resulted in better Li+ ion transport and enhanced electrochemical performances. The optimized cathode structure exhibited an initial specific capacity of 1274 mAh/g and a 0.06% decay rate per cycle at 0.5 C over 1000 cycles in LSBs.

5.
Small Methods ; 7(8): e2201598, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36807580

RESUMO

Magnesium metal batteries are promising candidates for next-generation high-energy-density and low-cost energy storage systems. Their application, however, is precluded by infinite relative volume changes and inevitable side reactions of Mg metal anodes. These issues become more pronounced at large areal capacities that are required for practical batteries. Herein, for the first time, double-transition-metal MXene films are developed to promote deeply rechargeable magnesium metal batteries using Mo2 Ti2 C3 as a representative example. The freestanding Mo2 Ti2 C3 films, which are prepared using a simple vacuum filtration method, possess good electronic conductivity, unique surface chemistry, and high mechanical modulus. These superior electro-chemo-mechanical merits of Mo2 Ti2 C3 films help to accelerate electrons/ions transfer, suppress electrolyte decomposition and dead Mg formation, as well as maintain electrode structural integrity during long-term and large-capacity operation. As a result, the as-developed Mo2 Ti2 C3 films exhibit reversible Mg plating/stripping with high Coulombic efficiency of 99.3% at a record-high capacity of 15 mAh cm-2 . This work not only sheds innovative insights into current collector design for deeply cyclable Mg metal anodes, but also paves the way for the application of double-transition-metal MXene materials in other alkali and alkaline earth metal batteries.

6.
Nano Lett ; 23(4): 1564-1572, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36749889

RESUMO

Highly reversible Mg battery chemistry demands a suitable electrolyte formulation highly compatible with currently available electrodes. In general, conventional electrolytes form a passivation layer on the Mg anode, requiring the use of MgCl2 additives that lead to severe corrosion of cell components and low anodic stability. Herein, for the first time, we conducted a comparative study of a series of Mg halides as potential electrolyte additives in conventional magnesium bis(hexamethyldisilazide)-based electrolytes. A novel electrolyte formulation that includes MgBr2 showed unprecedented performance in magnesium plating/stripping, with an average Coulombic efficiency of 99.26% over 1000 cycles at 0.5 mA/cm2 and 0.5 mAh/cm2. Further analysis revealed the in situ formation of a robust Mg anode-electrolyte interface, which leads to dendrite-free Mg deposition and stable cycling performance in a Mg-Mo6S8 battery over 100 cycles. This study demonstrates the rational formulation of a novel MgBr2-based electrolyte with high anodic stability of 3.1 V for promising future applications.

7.
Adv Mater ; 35(2): e2207310, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36308044

RESUMO

The creation of fluorinated interphase has emerged as an effective strategy for improving Li-metal anodes for rechargeable high-energy batteries. In contrast to the introduction of fluorine-containing species through widely adopted electrolyte engineering, a Li-metal composite design is reported in which LiF can locally redistribute on the Li-metal surface in liquid electrolytes via a dissolution-reprecipitation mechanism, and enable the formation of a high-fluorine-content solid electrolyte interphase (SEI). For validation, a Li/Li22 Sn5 /LiF ternary composite is investigated, where the as-formed LiF-rich SEI locks the active Li metal from corrosive electrolyte. The Li/Li22 Sn5 /LiF anode displays an impressive average Coulombic efficiency (ACE, ≈99.2%) at 1 mA cm-2 and 1 mAh cm-2 in a carbonate electrolyte and a remarkable cycling life of over 1600 h at 1 mA cm-2 and 2 mAh cm-2 . Applied to a LiCoO2 full cell with a high cathode areal capacity of 4.0 mAh cm-2 , a high capacity retention of ≈91.1% is realized for 100 cycles at 0.5 C between 2.8 to 4.5 V with a low negative/positive (N/P) ratio of 2:1. This design is conceptually different from the design employing the widely used fluorine-containing electrolyte additive and provides an alternative approach to realize reliable Li-metal batteries.

8.
Nano Lett ; 22(24): 10184-10191, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36475747

RESUMO

Two-dimensional metal dichalcogenides have demonstrated outstanding potential as cathodes for magnesium-ion batteries. However, the limited capacity, poor cycling stability, and severe electrode pulverization, resulting from lack of void space for expansion, impede their further development. In this work, we report for the first time, nickel sulfide (NiS2) hollow nanospheres assembled with nanoparticles for use as cathode materials in magnesium-ion batteries. Notably, the nanospheres were prepared by a one-step solvothermal process in the absence of an additive. The results show that regulating the synergistic effect between the rich anions and hollow structure positively affects its electrochemical performance. Crystallographic and microstructural characterizations reveal the reversible anionic redox of S2-/(S2)2-, consistent with density functional theory results. Consequently, the optimized cathode (8-NiS2 hollow nanospheres) could deliver a large capacity of 301 mA h g-1 after 100 cycles at 50 mA g-1, supporting the promising practical application of NiS2 hollow nanospheres in magnesium-ion batteries.

9.
Front Pharmacol ; 13: 1021655, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36545313

RESUMO

Objective: In animals, Helicobacter pylori (Hp)-induced gastric injury is accompanied by a decrease in the activity of the cysteine/glutamate transporter (xCT), which regulates extracellular glutamate levels. However, the impact of xCT activity in patients with Hp infection remains unclear. This study aims to investigate variations of xCT activity in the gastric mucosa of patients with Hp infection and to provide a clinical basis for identifying targets related to Hp infection. Methods: Our study included a total of 67 patients with gastritis, which consisted of 44 Hp-negative and 23 Hp-positive peptic ulcer cases. The inclusion criteria used to select patients were as follows: gastric histology was determined with a gastroscope, antral biopsies were taken for urease tests, and pathology and culture were performed for analysis of Hp-colonization. The clinical characteristics of the patients were obtained, the expressions of microRNAs and xCT protein were detected using immune histochemical analysis, and the concentration of glutamate in their gastric secretion was determined. Results: The findings revealed that xCT expression was significantly lower in Hp-positive patients as compared to Hp-negative individuals, which was accompanied by a decrease in glutamate concentration in gastric juice. We also discovered a high expression of microRNAs that have been shown to negatively regulate xCT expression, in Hp-positive patients. Conclusion: Reduced xCT activity in patients may play an important role in gastric ulcers caused by Hp infection. Our findings suggest that the microRNA/xCT pathway could be a potential treatment target for Hp-infection-related ulcers.

10.
Nano Lett ; 22(22): 9138-9146, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36354212

RESUMO

Owing to its high volumetric capacity and natural abundance, magnesium (Mg) metal has attracted tremendous attention as an ideal anode material for rechargeable Mg batteries. Despite Mg deposition playing an integral role in determining the cycling lifespan, its exact behavior is not clearly understood yet. Herein, for the first time, we introduce a facile approach to build magnesiophilic In/MgIn sites in situ on a Mg metal surface using InCl3 electrolyte additive for rechargeable Mg batteries. These magnesiophilic sites can regulate Mg deposition behaviors by homogenizing the distributions of Mg-ion flux and electric field at the electrode-electrolyte interphase, allowing flat and compact Mg deposition to inhibit short-circuiting. The as-designed Mg metal batteries achieve a stable cycling lifespan of 340 h at 1.0 mA cm-2 and 1.0 mAh cm-2 using Celgard separators, while the full cell coupled with Mo6S8 cathode maintains a high capacity retention of 95.5% over 800 cycles at 1 C.

11.
Front Pharmacol ; 13: 968098, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36249798

RESUMO

Stress ulcers are complicated by severe trauma and other critical diseases, the mechanism of which remains unclear. An increasing number of studies have shown that microRNAs (miRNAs) are important regulators of stress responses such as hypoxia, abnormal temperature, and inflammation. The evidence indicates that miRNAs are also involved in regulating stress-induced ulcers. Recently, we demonstrated that gastric mucosal injury induced by aspirin is related to the reduction of glutamate levels by inhibition of cystine/glutamate transporter (xCT) activity. In the present study, the effect of a miRNA/xCT on gastric mucosal injury induced by cold stimulation was investigated. We found that cold stimulation induced gastric mucosa injury with a reduction in glutamate levels and xCT activity and upregulation of miR-143, miR-152, and miR-181 expression. Exogenous glutamate significantly alleviated gastric mucosa injury by cold stimulation. In vitro experiments demonstrated that treatment with miR-143, miR-152, or miR-181 mimics directly induced cell damage. The effects of these mimics were alleviated by exogenous glutamate. The present study suggests that miR-143, miR-152, and miR-181 are involved in cold stimulation-induced acute gastric mucosal injury. Furthermore, the regulatory effect of miRNAs on gastric mucosa injury induced by cold stimulation is related to a decrease in glutamate release by reduction of cystine/glutamate transporter activity.

12.
Nano Lett ; 22(21): 8679-8687, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36315106

RESUMO

Two-dimensional MXenes produce competitive performances when incorporated into lithium-sulfur batteries (LSBs), solving key problems such as the poor electronic conductivity of sulfur and dissolution of its polysulfide intermediates. However, MXene nanosheets are known to easily aggregate and restack during electrode fabrication, filtration, or water removal, limiting their practical applicability. Furthermore, in complex electrocatalytic reactions like the multistep sulfur reduction process in LSBs, MXene alone is insufficient to ensure an optimal reaction pathway. In this work, we demonstrate for the first time a loose templating of sulfur spheres using Ti3C2Tx MXene nanosheets decorated with polymorphic CoSe2 nanoparticles. This work shows that the templating of sulfur spheres using nanoparticle-decorated MXene nanosheets can prevent nanosheet aggregation and exert a strong electrocatalytic effect, thereby enabling improved reaction kinetics and battery performance. The S@MXene-CoSe2 cathode demonstrated a long cycle life of 1000 cycles and a low capacity decay rate of 0.06% per cycle in LSBs.

13.
Eur J Pharmacol ; 931: 175196, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35987259

RESUMO

The senescence and dysfunction of vascular endothelial cells are important features of diabetic vascular disease. High mobility group box-1(HMGB1) may be involved in vascular injury in response to high glucose. Glycyrrhizin (GL) is an HMGB1 inhibitor that significantly reduces HMGB1. However, the relationship between HMGB1 and vascular ageing in diabetes is not clear, the protective mechanism of GL against vascular injury in type 2 diabetes mellitus (T2DM) is unclear too. This study aims to examine the role of HMGB1 in vascular endothelial cell senescence and the protective effects of GL on vascular aging in high fat diet/streptozotocin (HFD/STZ) induce type 2 diabetic rats.After induction of diabetes, GL (150 mg/kg/d) was treated by gavage for 4 weeks. Results showed that compared with the Control group, the serum level of HMGB1 was increased in rats with type 2 diabetes, while the expression of HMGB1 mRNA and protein in the thoracic aorta was upregulated, with a decrease in endothelium-dependent vasodilation function and an increase in aging degree in the thoracic aorta. However, the above indicators were significantly improved after GL treatment. In HUVECs, we found that treated with HMGB1 (50, 100 and 200 ng/ml) for 48 h induced cells senescence and GL (50, 100 mg/L) significantly inhibited high-glucose-induced endothelial cell senescence, meanwhile GL (50, 100 mg/L) significantly inhibited the high-glucose-induced HMGB1 release and upregulated p53 expression. In conclusion, GL as an HMGB1 inhibitor, attenuates endothelium-dependent relaxation impairment and vascular ageing in an animal model of diabetes and high-glucose-induced endothelial cell senescence.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Proteína HMGB1 , Lesões do Sistema Vascular , Animais , Senescência Celular , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Dieta Hiperlipídica , Células Endoteliais , Glucose , Ácido Glicirrízico/farmacologia , Ácido Glicirrízico/uso terapêutico , Proteína HMGB1/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Ratos , Ratos Sprague-Dawley , Estreptozocina
14.
Nano Lett ; 22(16): 6808-6815, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-35947428

RESUMO

Metallic magnesium is a promising high-capacity anode material for energy storage technologies beyond lithium-ion batteries. However, most reported Mg metal anodes are only cyclable under shallow cycling (≤1 mAh cm-2) and thus poor Mg utilization (<3%) conditions, significantly compromising their energy-dense characteristic. Herein, composite Mg metal anodes with high capacity utilization of 75% are achieved by coating magnesiophilic gold nanoparticles on copper foils for the first time. Benefiting from homogeneous ionic flux and uniform deposition morphology, the Mg-plated Au-Cu electrode exhibits high average Coulombic efficiency of 99.16% over 170 h cycling at 75% Mg utilization. Moreover, the full cell based on Mg-plated Au-Cu anode and Mo6S8 cathode achieves superior capacity retention of 80% after 300 cycles at a low negative/positive ratio of 1.33. This work provides a simple yet effective general strategy to enhance Mg utilization and reversibility, which can be extended to other metal anodes as well.

15.
Kaohsiung J Med Sci ; 38(2): 149-156, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34741409

RESUMO

Previous studies have demonstrated that the levels of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide (NO) synthesis, are strongly associated with hypertension, diabetes, and cardiovascular diseases. Profilin-1, an actin-binding protein, has been documented to be involved in endothelial injury and in the proliferation of vascular smooth muscle cells resulting from hypertension. However, the role of profilin-1 in ADMA-induced vascular injury in hypertension remains largely unknown. Forty healthy subjects and forty-two matched patients with essential hypertension were enrolled, and the related indexes of vascular injury in plasma were detected. Rat aortic smooth muscle cells (RASMCs) were treated with different concentrations of ADMA for different periods of time and transfected with profilin-1 small hairpin RNA to interrupt the expression of profilin-1. To determine the role of the Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) pathway, RASMCs were pretreated with AG490 or rapamycin. The expression of profilin-1 was tested using real-time polymerase chain reaction (PCR) and western blot analysis. Cell proliferation was measured by flow cytometry and 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazoliumbromide assays. Compared with healthy subjects, the levels of ADMA and profilin-1 were markedly elevated in hypertensive individuals, while the levels of NO were significantly decreased (p < 0.05). In vitro, studies showed ADMA-induced profilin-1 expression in a concentration- and time-dependent manner in RASMCs (p < 0.05), concomitantly with promoting the proliferation of RASMCs. Furthermore, ADMA-mediated proliferation of RASMCs and upregulation expression of profilin-1 were inhibited by blockade of the JAK2/STAT3 pathway or knockdown of profilin-1. Profilin-1 implicated in the ADMA-mediated vascular lesions in hypertension.


Assuntos
Arginina/análogos & derivados , Endotélio Vascular/efeitos dos fármacos , Hipertensão/etiologia , Miócitos de Músculo Liso/efeitos dos fármacos , Profilinas/fisiologia , Animais , Arginina/farmacologia , Arginina/fisiologia , Proliferação de Células , Endotélio Vascular/patologia , Humanos , Miócitos de Músculo Liso/patologia , Ratos
16.
Nano Lett ; 21(15): 6656-6663, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34291943

RESUMO

Lithium-sulfur (Li-S) batteries suffer from sluggish sulfur redox reactions under high-sulfur-loading and lean-electrolyte conditions. Herein, a typical Co@NC heterostructure composed of Co nanoparticles and a semiconductive N-doped carbon matrix is designed as a model Mott-Schottky catalyst to exert the electrocatalytic effect on sulfur electrochemistry. Theoretical and experimental results reveal the redistribution of charge and a built-in electric field at the Co@NC heterointerface, which are critical to lowering the energy barrier of polysulfide reduction and Li2S oxidation in the discharge and charge process, respectively. With Co@NC Mott-Schottky catalysts, the Li-S batteries display an ultrahigh capacity retention of 92.1% and a system-level gravimetric energy density of 307.8 Wh kg-1 under high S loading (10.73 mg cm-2) and lean electrolyte (E/S = 5.9 µL mgsulfur-1) conditions. The proposed Mott-Schottky heterostructure not only deepens the understanding of the electrocatalytic effect in Li-S chemistry but also inspires a rational catalyst design for advanced high-energy-density batteries.

17.
Mol Med Rep ; 23(1)2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33179114

RESUMO

Calcitonin gene­related peptide (CGRP) is the predominant neurotransmitter located in sensory nerves. This peptide is extensively distributed in central and peripheral tissues. CGRP causes relaxation of cardiovascular smooth muscle cells and confers protection against ischaemic myocardium and cardiac remodeling. The pharmacological effects of nitroglycerine and rutaecarpine have been demonstrated to be associated with an increase in the synthesis and release of CGRP. In the gastrointestinal tissues, CGRP participates in the regulation of gastrointestinal function, and exerts protective effects on gastric mucosa. Rutaecarpine, capsaicin and its derivatives, such as evodiamine, decrease gastric mucosal damage induced by several factors, including increased synthesis and release of CGRP. Taken together, this review focuses on the pharmacological effects of several CGRP related canonical drugs and suggests that synthesis and secretion of CGRP exhibit significant therapeutic effects in the occurrence and development of cardiovascular and gastrointestinal diseases.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Doenças Cardiovasculares/metabolismo , Gastroenteropatias/metabolismo , Alcaloides Indólicos/farmacologia , Nitroglicerina/farmacologia , Quinazolinas/farmacologia , Doenças Cardiovasculares/tratamento farmacológico , Gastroenteropatias/tratamento farmacológico , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Alcaloides Indólicos/uso terapêutico , Terapia de Alvo Molecular , Nitroglicerina/uso terapêutico , Quinazolinas/uso terapêutico , Regulação para Cima
18.
Clin Transl Gastroenterol ; 11(5): e00178, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32677810

RESUMO

INTRODUCTION: Helicobacter pylori infection is a major cause of gastrointestinal diseases. However, the pathogenesis of gastric mucosal injury by H. pylori remains unclear. Exogenous glutamate supplementation protects against gastric mucosal injury caused by H. pylori. Previously, we showed that aspirin-induced gastric injury is associated with reduction in glutamate release by inhibition of cystine-glutamate transporter (xCT) activity. We hypothesized that the xCT pathway is involved in H. pylori-induced gastric mucosal injury. In this study, we tested the activity of xCT and evaluated the regulatory effect of outer inflammatory protein (Oip) A on xCT in H. pylori-induced gastric mucosal injury. METHODS: In the H. pylori-infected mice and cell lines, the activity of xCT and the regulatory effect of microRNA on xCT were tested, and the effect of OipA from H. pylori on xCT activity was observed. RESULTS: The results of in vivo and in vitro experiments showed that H. pylori infection induced gastric mucosal injury. This was accompanied by a reduction in xCT activity, which was attenuated by exogenous glutamate treatment. Furthermore, the expression of miR-30b was upregulated, and miR-30b inhibitors significantly restored xCT activity and gastric mucosal injury caused by H. pylori infection. The OipA, a virulence protein from H. pylori, significantly upregulated the expression levels of miR-30b and inhibited xCT activity. DISCUSSION: OipA plays a significant role in H. pylori-induced gastric mucosal injury, and the effects are mediated by micro30b/xCT pathway.


Assuntos
Sistema y+ de Transporte de Aminoácidos/metabolismo , Proteínas da Membrana Bacteriana Externa/metabolismo , Mucosa Gástrica/patologia , Infecções por Helicobacter/patologia , Animais , Linhagem Celular , Modelos Animais de Doenças , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Helicobacter pylori/metabolismo , Helicobacter pylori/patogenicidade , Humanos , Masculino , Camundongos , MicroRNAs/metabolismo , Transdução de Sinais/genética , Regulação para Cima , Fatores de Virulência/metabolismo
19.
Mol Med Rep ; 22(2): 1227-1234, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32626984

RESUMO

Helicobacter pylori (Hp) infection is a major cause of gastrointestinal disease. However, the pathogenesis of gastric mucosa injury by Hp has remained elusive. Small non­coding RNA (sRNA) is a type of widespread RNA in prokaryotic organisms and regulates bacterial growth, reproduction and virulence. In the present study, Hp sRNA profiles were generated to reveal the sequences and possible functions of sRNA by bioinformatics analysis. The role of sRNA in tinidazole (TNZ) treatment was also explored. Total sRNAs of HP26695 were sequenced using an Illumina HiSeq2000. Detected Tags were then compared with a known sRNA database to build an sRNA profile. Reverse transcription­quantitative (RT­q)PCR products were sequenced directly and agarose gel electrophoresis was used to identify NAT­67 and 5'ureB­sRNA in HP. Furthermore, HP was treated with TNZ for 6, 12 and 24 h. The bacterial concentration was measured, the expression of NAT­67, 5'ureB­sRNA and ceuE was determined by RT­qPCR and superoxide dismutase (SOD) activity and reactive oxygen species (ROS) production were detected. A total of 163 sRNA tags were predicted in Hp through bioinformatics analysis. Among them, 35 tags were evolutionarily aconserved in different Hp strains. By target prediction, it was indicated that certain candidate sRNAs were associated with bacterial oxidative stress, virulence and chemotaxis. It was also observed that NAT­67 and 5'ureB­sRNA were downregulated in TNZ­treated HP. TNZ treatment inhibited the growth of Hp, which was accompanied by downregulation of ceuE and SOD activity, as well as upregulation of ROS. RNA sequencing and bioinformatics are valuable in predicting the expression profile and function of sRNA in HP. sRNA­targeted genes may be associated with virulence, oxidative stress and chemokines. Downregulation of NAT­67 by TNZ may be involved in Hp oxidative stress regulation, which may comprise one of the mechanisms of the antibacterial effects of TNZ.


Assuntos
Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Helicobacter pylori , RNA Bacteriano/genética , Pequeno RNA não Traduzido/genética , Tinidazol/farmacologia , Virulência/genética , Quimiocinas/metabolismo , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/genética , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
20.
Cardiovasc Toxicol ; 20(5): 507-519, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32607760

RESUMO

Doxorubicin (Dox) is widely used in cancer therapy, but the clinical application is limited by its cardiotoxicity. The underlying mechanism of Dox-induced cardiotoxicity remains unclear. Present study aimed to evaluate the role of NLRP3 inflammasome in Dox-induced cardiotoxicity. The NLRP3 inflammasome was activated in the myocardium of Dox-treating (5 mg/kg, once every other day, cumulative dosage to 15 mg/kg and sacrificed after 2 days of last Dox injection) C57BL/6 mice as shown by the up-regulation of NLRP3 and Caspase-1 p20. Dox (1 µM for 48 h) induced the apoptosis of H9c2 cells and primary cardiomyocytes concomitantly with up-regulation of NLRP3, ASC and Caspase-1 p20 expressions, as well as the increased IL-1ß secretion, suggesting the activation of NLRP3 inflammasome. These effects of Dox on H9c2 cells and primary cardiomyocytes can be reversed by MCC950, a specific inhibitor of NLRP3. In view of the key role of ROS on the Dox-induced cardiotoxicity, the relationship between ROS and NLRP3 was further investigated. The ROS level was increased in myocardium, H9c2 cells and primary cardiomyocytes after treating with Dox. Decreasing ROS level by NAC can inhibit the NLRP3 inflammasome activation, secretion of IL-1ß and apoptosis in Dox-treating H9c2 cells and primary cardiomyocytes. Collectively, this study reveals a crucial role of ROS/NLRP3-associated inflammasome activation in Dox-induced cardiotoxicity, and NLRP3 inflammasome may represent a new therapeutic target for Dox-induced cardiotoxicity.


Assuntos
Doxorrubicina , Cardiopatias/metabolismo , Inflamassomos/metabolismo , Miócitos Cardíacos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Animais , Apoptose , Cardiotoxicidade , Linhagem Celular , Modelos Animais de Doenças , Cardiopatias/induzido quimicamente , Cardiopatias/patologia , Interleucina-1beta/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/patologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
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