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1.
Molecules ; 29(7)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38611739

RESUMO

In this paper, we study the drift behavior of organic electrochemical transistor (OECT) biosensors in a phosphate-buffered saline (PBS) buffer solution and human serum. Theoretical and experimental methods are illustrated in this paper to understand the origin of the drift phenomenon and the mechanism of ion diffusion in the sensing layer. The drift phenomenon is explained using a first-order kinetic model of ion adsorption into the gate material and shows very good agreement with experimental data on drift in OECTs. We show that the temporal current drift can be largely mitigated using a dual-gate OECT architecture and that dual-gate-based biosensors can increase the accuracy and sensitivity of immuno-biosensors compared to a standard single-gate design. Specific binding can be detected at a relatively low limit of detection, even in human serum.


Assuntos
Projetos de Pesquisa , Humanos , Adsorção , Difusão , Cinética
2.
Front Pharmacol ; 15: 1336693, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38370481

RESUMO

The pathological mechanisms and treatments of osteoarthritis (OA) are critical topics in medical research. This paper reviews the regulatory mechanisms of hydrogen sulfide (H2S) in OA and the therapeutic potential of H2S donors. The review highlights the importance of changes in the endogenous H2S pathway in OA development and systematically elaborates on the role of H2S as a third gaseous transmitter that regulates inflammation, oxidative stress, and pain associated with OA. It also explains how H2S can lessen bone and joint inflammation by inhibiting leukocyte adhesion and migration, reducing pro-inflammatory mediators, and impeding the activation of key inflammatory pathways such as nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK). Additionally, H2S is shown to mitigate mitochondrial dysfunction and endoplasmic reticulum stress, and to modulate Nrf2, NF-κB, PI3K/Akt, and MAPK pathways, thereby decreasing oxidative stress-induced chondrocyte apoptosis. Moreover, H2S alleviates bone and joint pain through the activation of Kv7, K-ATP, and Nrf2/HO-1-NQO1 pathways. Recent developments have produced a variety of H2S donors, including sustained-release H2S donors, natural H2S donors, and synthetic H2S donors. Understanding the role of H2S in OA can lead to the discovery of new therapeutic targets, while innovative H2S donors offer promising new treatments for patients with OA.

3.
Eur J Pharmacol ; 963: 176265, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38070636

RESUMO

Hydrogen sulfide (H2S), a colorless exhaust gas, has been traditionally considered an air pollutant. However, recent studies have revealed that H2S functions as a novel gas signaling molecule, exerting diverse biological effects on various systems, including the cardiovascular, digestive, and nervous systems. Thus, H2S is involved in various pathophysiological processes. As H2S affects reproductive function, it has potential therapeutic implications in reproductive system diseases. This review examined the role of H2S in various female reproductive organs, including the ovary, fallopian tube, vagina, uterus, and placenta. Additionally, the regulatory function of H2S in the female reproductive system has been discussed to provide useful insights for developing clinical therapeutic strategies for reproductive diseases.


Assuntos
Sistema Cardiovascular , Sulfeto de Hidrogênio , Feminino , Humanos , Sulfeto de Hidrogênio/farmacologia , Sulfeto de Hidrogênio/uso terapêutico , Ovário , Útero , Transdução de Sinais
4.
Front Pharmacol ; 14: 1303465, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074127

RESUMO

Hydrogen sulfide (H2S) and sulfur dioxide (SO2), recognized as endogenous sulfur-containing gas signaling molecules, were the third and fourth molecules to be identified subsequent to nitric oxide and carbon monoxide (CO), and exerted diverse biological effects on the cardiovascular system. However, the exact mechanisms underlying the actions of H2S and SO2 have remained elusive until now. Recently, novel post-translational modifications known as S-sulfhydration and S-sulfenylation, induced by H2S and SO2 respectively, have been proposed. These modifications involve the chemical alteration of specific cysteine residues in target proteins through S-sulfhydration and S-sulfenylation, respectively. H2S induced S-sulfhydrylation can have a significant impact on various cellular processes such as cell survival, apoptosis, cell proliferation, metabolism, mitochondrial function, endoplasmic reticulum stress, vasodilation, anti-inflammatory response and oxidative stress in the cardiovascular system. Alternatively, S-sulfenylation caused by SO2 serves primarily to maintain vascular homeostasis. Additional research is warranted to explore the physiological function of proteins with specific cysteine sites, despite the considerable advancements in comprehending the role of H2S-induced S-sulfhydration and SO2-induced S-sulfenylation in the cardiovascular system. The primary objective of this review is to present a comprehensive examination of the function and potential mechanism of S-sulfhydration and S-sulfenylation in the cardiovascular system. Proteins that undergo S-sulfhydration and S-sulfenylation may serve as promising targets for therapeutic intervention and drug development in the cardiovascular system. This could potentially expedite the future development and utilization of drugs related to H2S and SO2.

5.
Small ; : e2310527, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38050933

RESUMO

This paper reports a new mechanism for particulate matter detection and identification. Three types of carbon particles are synthesized with different functional groups to mimic the real particulates in atmospheric aerosol. After exposing polymer-based organic devices in organic field effect transistor (OFET) architectures to the particle mist, the sensitivity and selectivity of the detection of different types of particles are shown by the current changes extracted from the transfer curves. The results indicate that the sensitivity of the devices is related to the structure and functional groups of the organic semiconducting layers, as well as the morphology. The predominant response is simulated by a model that yielded values of charge carrier density increase and charge carriers delivered per unit mass of particles. The research points out that polymer semiconductor devices have the ability to selectively detect particles with multiple functional groups, which reveals a future direction for selective detection of particulate matter.

6.
Angew Chem Int Ed Engl ; 62(23): e202219313, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37021740

RESUMO

N-Type thermoelectrics typically consist of small molecule dopant+polymer host. Only a few polymer dopant+polymer host systems have been reported, and these have lower thermoelectric parameters. N-type polymers with high crystallinity and order are generally used for high-conductivity ( σ ${\sigma }$ ) organic conductors. Few n-type polymers with only short-range lamellar stacking for high-conductivity materials have been reported. Here, we describe an n-type short-range lamellar-stacked all-polymer thermoelectric system with highest σ ${\sigma }$ of 78 S-1 , power factor (PF) of 163 µW m-1 K-2 , and maximum Figure of merit (ZT) of 0.53 at room temperature with a dopant/host ratio of 75 wt%. The minor effect of polymer dopant on the molecular arrangement of conjugated polymer PDPIN at high ratios, high doping capability, high Seebeck coefficient (S) absolute values relative to σ ${\sigma }$ , and atypical decreased thermal conductivity ( κ ${\kappa }$ ) with increased doping ratio contribute to the promising performance.

7.
Biomater Sci ; 11(8): 2828-2844, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36857622

RESUMO

Bacteria eradication and subsequent periodontal tissue reconstruction is the primary task for periodontitis treatment. Commonly used antibiotic therapy suffers from antibiotic resistance. Meanwhile, promoting fibroblast activity is crucial for re-establishing a damaged periodontal structure. In addition to the fibroblast activation property of Mg2+, photobiomodulation (PBM) has recently attracted increasing attention in wound healing. Using the same 635 nm laser resource, PBM could simultaneously work with antibacterial photodynamic therapy (aPDT) to achieve antibacterial function and fibroblast activation effect. Herein, multifunctional microspheres were designed by employing poly (lactic-co-glycolic acid) (PLGA) microspheres to load tetrakis (4-carboxyphenyl) porphyrin (TCPP) and magnesium oxide (MgO) nanoparticles, named as PMT, with sustained Mg2+ release for 20 days. PMT achieved excellent antibacterial photodynamic effect for periodontal pathogens F. nucleatum and P. gingivalis by generating reactive oxygen species, which increases cell membrane permeability and destroys bacteria integrity to cause bacteria death. Meanwhile, PMT itself exhibited improved fibroblast viability and adhesion, with the PMT + light group revealing further activation of fibroblast cells, suggesting the coordinated action of Mg2+ and PBM effects. The underlying molecular mechanism might be the elevated gene expressions of Fibronectin 1, Col1a1, and Vinculin. In addition, the in vivo rat periodontitis model proved the superior therapeutic effects of PMT with laser illumination using micro-computed tomography analysis and histological staining, which presented decreased inflammatory cells, increased collagen production, and higher alveolar bone level in the PMT group. Our study sheds light on a promising strategy to fight periodontitis using versatile microspheres, which combine aPDT and PBM-assisted fibroblast activation functions.


Assuntos
Periodontite , Fotoquimioterapia , Ratos , Animais , Óxido de Magnésio , Microesferas , Microtomografia por Raio-X , Fotoquimioterapia/métodos , Periodontite/tratamento farmacológico , Periodontite/microbiologia , Antibacterianos/farmacologia
8.
Front Cell Dev Biol ; 11: 1332049, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38259518

RESUMO

The Keap1-Nrf2 signaling pathway plays a crucial role in cellular defense against oxidative stress-induced damage. Its activation entails the expression and transcriptional regulation of several proteins involved in detoxification and antioxidation processes within the organism. Keap1, serving as a pivotal transcriptional regulator within this pathway, exerts control over the activity of Nrf2. Various post-translational modifications (PTMs) of Keap1, such as alkylation, glycosylation, glutathiylation, S-sulfhydration, and other modifications, impact the binding affinity between Keap1 and Nrf2. Consequently, this leads to the accumulation of Nrf2 and its translocation to the nucleus, and subsequent activation of downstream antioxidant genes. Given the association between the Keap1-Nrf2 signaling pathway and various diseases such as cancer, neurodegenerative disorders, and diabetes, comprehending the post-translational modification of Keap1 not only deepens our understanding of Nrf2 signaling regulation but also contributes to the identification of novel drug targets and biomarkers. Consequently, this knowledge holds immense importance in the prevention and treatment of diseases induced by oxidative stress.

9.
J Mater Sci Mater Med ; 33(10): 73, 2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36209337

RESUMO

Although titanium (Ti) and Ti-based alloy have been widely used as dental and orthopedic implant materials, its bioinertness hindered the rapid osseointegration. Therefore, it is recommended to acquire ideal topographic and chemical characteristics through surface modification methods. 3D printing is a delicate manufacture technique which possesses superior controllability and reproducibility. While aspirin serve as a well-established non-steroidal anti-inflammatory agent. Recently, the importance of immune system in regulating bone dynamics has attracted increasing attention. We herein superimposed the aspirin/poly (lactic-co-glycolic acid) (ASP/PLGA) coating on the 3D-printed Ti-6Al-4V surface with uniform micro-structure to establish the Ti64-M-ASP/PLGA substrate. Scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS) and contact angle test confirmed the successful fabrication of the Ti64-M-ASP/PLGA substrate, with increased wettability and sustained release pattern of ASP. Compared with the Ti64 base material, the Ti64-M-ASP/PLGA substrate showed enhanced M2 and depressed M1 genes and proteins expressions in macrophages. The novel Ti64-M-ASP/PLGA substrate also displayed enhanced osteoblast proliferation, adhesion, extracellular mineralization ability and osteogenic gene expressions when cultured with macrophage conditioned medium in vitro. Furthermore, rat femora implantation model was used for in vivo evaluation. After 4 weeks of implantation, push out test, micro-computed tomography (micro-CT) and histological analyses all confirmed the superior osseointegration capabilities of the Ti64-M-ASP/PLGA implant than the other groups. Our study revealed the synergistic role played by 3D-printed micro topography and immunoregulatory drug aspirin in promoting osteogenesis in vitro and accelerating osseointegration in vivo, thus providing a promising method for better modifying the implant surface. Graphical abstract.


Assuntos
Osseointegração , Titânio , Ligas/farmacologia , Animais , Anti-Inflamatórios não Esteroides , Aspirina/farmacologia , Meios de Cultivo Condicionados/farmacologia , Preparações de Ação Retardada , Macrófagos , Osteoblastos , Osteogênese , Impressão Tridimensional , Ratos , Reprodutibilidade dos Testes , Propriedades de Superfície , Titânio/química , Microtomografia por Raio-X
10.
Materials (Basel) ; 15(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36079344

RESUMO

Host immune response has gradually been accepted as a critical factor in achieving successful implant osseointegration. The aim of this study is to create a favorable immune microenvironment by the dominant release of IL-4 during the initial few days after implant insertion to mitigate early inflammatory reactions and facilitate osseointegration. Herein, the B-TNT/PDA/IL-4 substrate was established by immobilizing an interleukin-4 (IL-4)/polydopamine (PDA) coating on a black TiO2 nanotube (B-TNT) surface, achieving on-demand IL-4 release under near infrared (NIR) irradiation. Gene Ontology (GO) enrichment analyses based on high-throughput DNA microarray data revealed that IL-4 addition inhibited osteoclast differentiation and function. Animal experiment results suggested that the B-TNT/PDA/IL-4+Laser substrate induced the least inflammatory, tartrate-resistant acid phosphatase, inducible nitric oxide synthase and the most CD163 positive cells, compared to the Ti group at 7 days post-implantation. In addition, 28 days post-implantation, micro-computed tomography results showed the highest bone volume/total volume, trabecular thickness, trabecular number and the lowest trabecular separation, while Hematoxylin-eosin and Masson-trichrome staining revealed the largest amount of new bone formation for the B-TNT/PDA/IL-4+Laser group. This study revealed the osteoimmunoregulatory function of the novel B-TNT/PDA/IL-4 surface by photothermal release of IL-4 at an early period post-implantation, thus paving a new way for dental implant surface modification.

11.
Biosens Bioelectron ; 216: 114691, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36113388

RESUMO

We developed new measurement configurations based on organic electrochemical transistors (OECTs). Three types of COOH-functionalized bioreceptor layers were deposited on indium tin oxide (ITO) electrodes on poly(ethylene terephthalate) (PET) substrates and their performance was tested using single gate functionalization organic electrochemical transistor (S-OECT) and dual gate functionalization organic electrochemical transistor (D-OECT) configurations. The three layers included one p-type semiconductor, one insulator, and one self-assembled layer, and the dual gates were connected in series through buffer solutions, so the solution-electrode interfaces had the opposite polarities. We investigated the sensitivities of these systems using the human IgG antigen-human IgG antibody receptor pair for main experiments, and drifts of antibody-functionalized gates without analytes as control experiments. Drifts without analyte can obscure the real sensitivity. We show that the D-OECT has the capability to cancel the drifts, and is also beneficial for showing the sensitivity more exactly. This configuration has the ability to increase the accuracy of antibody-antigen interaction detection, and further decrease or eliminate the effect of ions in the buffer solution. We also prove that the D-OECT can work well with different bioreceptor materials, which indicates that the system can be further applied to different conditions.


Assuntos
Técnicas Biossensoriais , Eletrodos , Etilenos , Humanos , Imunoglobulina G , Íons
12.
Redox Biol ; 48: 102192, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34818607

RESUMO

OBJECTIVE: This study aimed to determine the communicational pattern of gaseous signaling molecules sulfur dioxide (SO2) and nitric oxide (NO) between vascular endothelial cells (VECs) and vascular smooth muscle cells (VSMCs), and elucidate the compensatory role and significance of endogenous SO2 in the development of hypertension due to NO deficiency. APPROACH AND RESULTS: Blood pressure was monitored by the tail-cuff and implantable physiological signal telemetry in L-nitro-arginine methyl ester (l-NAME)-induced hypertensive mice, and structural alterations of mouse aortic vessels were detected by the elastic fiber staining method. l-NAME-treated mice showed decreased plasma NO levels, increased SO2 levels, vascular remodeling, and increased blood pressure, and application of l-aspartate-ß-hydroxamate, which inhibits SO2 production, further aggravated vascular structural remodeling and increased blood pressure. Moreover, in a co-culture system of HAECs and HASMCs, NO from HAECs did not influence aspartate aminotransferase (AAT)1 protein expression but decreased AAT1 activity in HASMCs, thereby resulting in the inhibition of endogenous SO2 production. Furthermore, NO promoted S-nitrosylation of AAT1 protein in HASMCs and purified AAT1 protein. Liquid chromatography with tandem mass spectrometry showed that the Cys192 site of AAT1 purified protein was modified by S-nitrosylation. In contrast, dithiothreitol or C192S mutations in HASMCs blocked NO-induced AAT1 S-nitrosylation and restored AAT1 enzyme activity. CONCLUSION: Endothelium-derived NO inhibits AAT activity by nitrosylating AAT1 at the Cys192 site and reduces SO2 production in HASMCs. Our findings suggest that SO2 acts as a compensatory defense system to antagonize vascular structural remodeling and hypertension when the endogenous NO pathway is disturbed.

13.
Artigo em Inglês | MEDLINE | ID: mdl-34326887

RESUMO

Application of the anticancer drug doxorubicin (DOX) is restricted due to its adverse, cardiotoxic side effects, which ultimately result in heart failure. Moreover, there are a limited number of chemical agents for the clinical prevention of DOX-induced cardiotoxicity. Based on the theories of traditional Chinese medicine (TCM) on chronic heart failure (CHF), Shenlijia (SLJ), a new TCM compound, has been developed to fulfill multiple functions, including improving cardiac function and inhibiting cardiac fibrosis. In the present study, the protective effects and molecular mechanisms of SLJ on DOX-induced CHF rats were investigated. The CHF rat model was induced by intraperitoneal injection of DOX for six weeks with the cumulative dose of 15 mg/kg. All rats were then randomly divided into the control, CHF, CHF + SLJ (3.0 g/kg per day), and CHF + captopril (3.8 mg/kg per day) groups and treated for further four weeks. Echocardiography and the assessment of hemodynamic parameters were performed to evaluate heart function. A protein chip was applied to identify proteins with diagnostic values that were differentially expressed following SLJ treatment. The data from these investigations showed that SLJ treatment significantly improved cardiac function by increasing the left ventricular ejection fraction, improving the hemodynamic index, and inhibiting interstitial fibrosis. Protein chip analysis revealed that SLJ upregulated MCP-1, MDC, neuropilin-2, TGF-ß3, thrombospondin, TIE-2, EG-VEGF/PK1, and TIMP-1/2/3 expressions and downregulated that of MMP-13. In addition, immunohistochemistry and western blot results further confirmed that SLJ promoted TIMP-1/2/3 and inhibited MMP-13 expression. The results of the present study suggest that SLJ was effective against DOX-induced CHF rats and is related to the improvement of heart function and ultrastructure and the inhibition of myocardial fibrosis.

14.
J Glob Antimicrob Resist ; 27: 75-78, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34284126

RESUMO

OBJECTIVES: The emergence of colistin-resistant Klebsiella pneumoniae (CoRKp) is a serious public-health issue as colistin is the last line of defence against infections caused by multidrug-resistant Gram-negative bacteria. In this study, we generated a draft genome sequence for CoRKp strain P094-1 isolated from a sputum sample of an infected patient. METHODS: Whole genomic DNA of strain P094-1 was sequenced using a PacBio sequencing platform. Generated reads were de novo assembled using Hierarchical Genome Assembly Process (HGAP) v.3.0. Colistin resistance-related genes were predicted from the genome sequence and were validated experimentally. RESULTS: The genome of strain P094-1 lacked a 20.3-kb region, including complete deletion of the mgrB gene. Molecular and genome sequencing-based analyses revealed that the observed colistin resistance of P094-1 could not be attributed to plasmid-borne genes mcr-1 to mcr-9 or to alteration of the pmr and pho operons (deletions, insertions or substitutions), but was conferred by an insertion sequence 1 (IS1)-induced total deletion of mgrB. CONCLUSION: This is the first reported whole-genome sequence of an unusual CoRKp isolate containing an IS1-induced deletion of mgrB.


Assuntos
Colistina , Infecções por Klebsiella , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Colistina/farmacologia , Genômica , Humanos , Klebsiella pneumoniae/genética
15.
J Adv Res ; 29: 55-65, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33842005

RESUMO

Introduction: Mast cell (MC) degranulation is an important step in the pathogenesis of inflammatory reactions and allergies; however, the mechanism of stabilizing MC membranes to reduce their degranulation is unclear. Methods: SO2 content in MC culture supernatant was measured by HPLC-FD. The protein and mRNA expressions of the key enzymes aspartate aminotransferase 1 (AAT1) and AAT2 and intracellular AAT activity were detected. The cAMP level in MCs was detected by immunofluorescence and ELISA. The release rate of MC degranulation marker ß-hexosaminidase was measured. The expression of AAT1 and cAMP, the MC accumulation and degranulation in lung tissues were detected. Objectives: To exam whether an endogenous sulfur dioxide (SO2) pathway exists in MCs and if it serves as a novel endogenous MC stabilizer. Results: We firstly show the existence of the endogenous SO2/AAT pathway in MCs. Moreover, when AAT1 was knocked down in MCs, MC degranulation was significantly increased, and could be rescued by a SO2 donor. Mechanistically, AAT1 knockdown decreased the cyclic adenosine monophosphate (cAMP) content in MCs, while SO2 prevented this reduction in a dose-independent manner. Pretreatment with the cAMP-synthesizing agonist forskolin or the cAMP degradation inhibitor IBMX significantly blocked the increase in AAT1 knockdown-induced MC degranulation. Furthermore, in hypoxia-stimulated MCs, AAT1 protein expression and SO2 production were markedly down regulated, and MC degranulation was activated, which were blunted by AAT1 overexpression. The cAMP synthesis inhibitor SQ22536 disrupted the suppressive effect of AAT1 overexpression on hypoxia-induced MC degranulation. In a hypoxic environment, mRNA and protein expression of AAT1 was significantly reduced in lung tissues of rats. Supplementation of SO2 elevated the cAMP level and reduced perivascular MC accumulation and degranulation in lung tissues of rats exposed to a hypoxic environment in vivo. Conclusion: SO2 serves as an endogenous MC stabilizer via upregulating the cAMP pathway under hypoxic circumstance.


Assuntos
Degranulação Celular , Hipóxia/metabolismo , Mastócitos/metabolismo , Dióxido de Enxofre/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , AMP Cíclico/metabolismo , Regulação para Baixo , Humanos , Inflamação/metabolismo , Pulmão/metabolismo , Masculino , Ratos , Ratos Wistar , Transdução de Sinais , beta-N-Acetil-Hexosaminidases/metabolismo
16.
J Adv Res ; 27: 155-164, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33318874

RESUMO

INTRODUCTION: The proliferation of vascular smooth muscle cells (VSMCs) is an important physiological and pathological basis for many cardiovascular diseases. Endogenous hydrogen sulfide (H2S), the third gasotransmitter, is found to preserve vascular structure by inhibiting VSMC proliferation. However, the mechanism by which H2S suppresses VSMC proliferation has not been fully clear. OBJECTIVES: This study aimed to explore whether H2S persulfidates the transcription factor FOXO1 to inhibit VSMC proliferation. METHODS: After the proliferation of VSMC A7r5 cells was induced by endothelin-1 (ET-1), FOXO1 phosphorylation and proliferating cell nuclear antigen (PCNA) expression were detected by Western blotting, the degree of FOXO1 nuclear exclusion and PCNA fluorescent signals in the nucleus were detected by immunofluorescence, and the persulfidation of FOXO1 was measured through a biotin switch assay. RESULTS: The results showed that ET-1 stimulation increased cell proliferation, FOXO1 phosphorylation and FOXO1 nuclear exclusion to the cytoplasm in the cells. However, pretreatment with NaHS, an H2S donor, successfully abolished the ET-1-induced increases in the VSMC proliferation, FOXO1 phosphorylation, and FOXO1 nuclear exclusion to the cytoplasm. Mechanistically, H2S persulfidated the FOXO1 protein in A7r5 and 293T cells, and the thiol reductant DTT reversed this effect. Furthermore, the C457S mutation of FOXO1 abolished the H2S-induced persulfidation of FOXO1 in the cells and the subsequent inhibitory effects on FOXO1 phosphorylation at Ser256, FOXO1 nuclear exclusion to the cytoplasm and cell proliferation. CONCLUSION: Thus, our findings demonstrated that H2S might inhibit VSMC proliferation by persulfidating FOXO1 at Cys457 and subsequently preventing FOXO1 phosphorylation at Ser256.

17.
ACS Appl Mater Interfaces ; 12(40): 45036-45044, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32924437

RESUMO

Ionic doping effects in conjugated polymers often cause nonspecific signaling and a low selectivity of bioelectronic sensing. Using remote-gate field-effect transistor characterization of molecular and ionic doping in poly(3-hexylthiophene) (P3HT) and acid-functionalized polythiophene, poly[3-(3-carboxypropyl) thiophene-2,5-diyl] (PT-COOH), we discovered that proton doping effects on the interfacial potential occurring in P3HT could be suppressed by sequentially doping P3HT by 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ). To be specific, intrinsic pH sensitivity shown by pure P3HT (18 mV/pH in a range from pH 3 to 9) was fully dissipated for doped P3HT:F4TCNQ. However, F4TCNQ sequential doping instead increases pH sensitivity of acid-functionalized polythiophene, PT-COOH (40 mV/pH), compared to that of a pure PT-COOH (30 mV/pH). Interactions between polythiophene backbone and side chains, which constrain the activity of COOH, are weakened by stronger F4TCNQ doping leaving behind responsive COOH groups exposed to aqueous solutions. This is supported by the reduced pH sensitivity of PT-COOH sequentially doped by a weaker dopant, tetracyanoethylene (TCNE) (21 mV/pH). Thus, doping is shown to stabilize a nonpolar conjugated polymer to pH-induced fluctuations on one hand, and to activate a COOH side chain to pH-induced response on the other.


Assuntos
Técnicas Biossensoriais , Polímeros/química , Concentração de Íons de Hidrogênio , Íons/química , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
18.
Int J Nanomedicine ; 15: 5061-5072, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764936

RESUMO

PURPOSE: Zirconia is one of the most promising implant materials due to its favorable physical, mechanical and biological properties. However, until now, we know little about the mechanism of osseointegration on zirconia. The purpose of this study is to evaluate the effect of Syndecan (Sdc) on osteoblastic cell (MC3T3-E1) adhesion and proliferation onto zirconia materials. MATERIALS AND METHODS: The mirror-polished disks 15 mm in diameter and 1.5 mm in thick of commercial pure titanium (CpTi), 3mol% yttria-stabilized tetragonal zirconia polycrystalline (3Y-TZP) and nano-zirconia (NanoZr) are used in this study. MC3T3-E1 cells were seeded onto specimen surfaces and subjected to RNA interference (RNAi) for Syndecan-1, Syndecan-2, Syndecan-3, and Syndecan-4. At 48h post-transfection, the cell morphology, actin cytoskeleton, and focal adhesion were observed using scanning electron microscopy or laser scanning confocal fluorescence microscopy. At 24h and 48h post-transfection, cell counting kit-8 (CCK-8) assay was used to investigate cell proliferation. RESULTS: The cell morphology of MC3T3-E1 cells on CpTi, 3Y-TZP, and NanoZr changed into abnormal shape after gene silencing of Syndecan. Among the Syndecan family, Sdc-2 is responsible for NanoZr-specific morphology regulation, via maintenance of cytoskeletal conformation without affecting cellular attachment. According to CCK-8 assay, Sdc-2 affects the osteoblastic cell proliferation onto NanoZr. CONCLUSION: Within the limitation of this study, we suggest that Syndecan affects osteoblastic cell adhesion on CpTi, 3Y-TZP, and NanoZr. Sdc-2 might be an important heparin-sensitive cell membrane regulator in osteoblastic cell adhesion, specifically on NanoZr, through the organization of actin cytoskeleton and affects osteoblastic cell proliferation.


Assuntos
Osseointegração/fisiologia , Osteoblastos/citologia , Osteoblastos/fisiologia , Sindecanas/metabolismo , Citoesqueleto de Actina/efeitos dos fármacos , Animais , Adesão Celular/fisiologia , Membrana Celular/efeitos dos fármacos , Proliferação de Células/fisiologia , Células Cultivadas , Camundongos , Microscopia Eletrônica de Varredura , Osseointegração/genética , Propriedades de Superfície , Sindecana-2/genética , Sindecana-2/metabolismo , Sindecanas/genética , Titânio/química , Ítrio/química , Zircônio/química
19.
Pharm Biol ; 58(1): 417-426, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32429724

RESUMO

Context: Therapeutic doxorubicin administration is restricted as this anticancer drug may be cardiotoxic. The traditional Chinese medicine qiliqiangxin has been approved for clinical treatment of chronic heart failure.Objective: To explore the protective effects and molecular mechanisms of qiliqiangxin on doxorubicin-induced congestive heart failure (CHF) in rats.Materials and methods: A CHF rat model was established via intraperitoneal DOX injections (2.5 mg/kg/week) for 6 weeks. The rats were randomly assigned to control, CHF, CHF + QL (1.0 g/kg/d), or captopril (3.8 mg/kg/d) treatment groups (n = 10) for 4 weeks. MicroRNA sequencing elucidated the molecular mechanisms of qiliqiangxin on doxorubicin-induced CHF in rats.Results: Unlike in the CHF group, QL significantly reduced Bax:Bcl-2 (2.05 ± 0.23 vs. 0.94 ± 0.09, p < 0.05) and the levels of collagen I (0.19 ± 0.02 vs. 0.15 ± 0.01, p < 0.05), collagen III (0.19 ± 0.02 vs. 0.14 ± 0.02, p < 0.05), TGF-ß1 (5.28 ± 0.89 vs. 2.47 ± 0.51, p < 0.05), Smad3 (1.23 ± 0.12 vs. 0.78 ± 0.09, p < 0.05), MMP-2 (0.89 ± 0.01 vs. 0.53 ± 0.05, p < 0.05), and TIMP-2 (0.24 ± 0.03 vs. 0.44 ± 0.03, p < 0.05). QL also upregulated TGF-ß3 (0.65 ± 0.06 vs. 0.96 ± 0.10, p < 0.05) and Smad7 (0.09 ± 0.01 vs. 0.19 ± 0.023, p < 0.05). Moreover, Smad3 was a target of miR-345-3p.Discussion and Conclusions: The beneficial effects of QL on DOX-induced CHF in rats are mediated by reduction in myocardial fibrosis, promotion of TGF-ß3/Smad7, and inhibition of TGF-ß1/Smad3. QL may also modulate specific miRNAs. These results provide evidence that QL might be an effective treatment for DOX-induced CHF.


Assuntos
Doxorrubicina/toxicidade , Medicamentos de Ervas Chinesas/uso terapêutico , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/tratamento farmacológico , Remodelação Ventricular/efeitos dos fármacos , Animais , Antibióticos Antineoplásicos/toxicidade , Medicamentos de Ervas Chinesas/farmacologia , Insuficiência Cardíaca/patologia , Masculino , Ratos , Ratos Wistar , Remodelação Ventricular/fisiologia
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