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1.
Chemosphere ; 361: 142554, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38851502

ABSTRACT

Increasing multidrug-resistant pathogenic microbial around the world become a global problem, making it imperative to develop effective methods for bacterial inactivation in wastewater. In this study, we propose a multifunctional photoelectrochemical (PEC) system to successfully disinfect microbial cells and degrade orange (II) dyes. CoOx NP were synthesized by spin-coating onto hydrothermally synthesized TiO2 nanorod arrays followed by electrodeposited NiFe-LDH to develop the NiFe-LDH/CoOx NP-TiO2 NRs. Interestingly, spin-coated CoOx NP-TiO2 NRs exhibited a 1.5-fold enhancement in photocurrent (1.384 mA/cm2) than pristine TiO2 NRs (0.92 mA/cm2). A NiFe-layered double hydroxide (LDH) cocatalysts layer further exhibits the maximum photocurrent density of 1.64 mA/cm2 with IPCE of 84.5% at 1.0 VAg/AgCl at 380 nm. Furthermore, NiFe-LDH/CoOx-TiO2 NR photoanodes were effectually employed for photoelectrochemical bacteria disinfection and organic pollutant removals. With NiFe-LDH/CoOx-TiO2 NR, 99% (120 min) bacterial inactivation and 99% (60 min) orange II dye decomposition efficiency was achieved. Superoxide radicals (-O2•), hydroxyl radicals (HO•), and holes (h+) played a critical role in the PEC degradation systems. Due to the synergy between NiFe-LDH cocatalyst and CoOx interlayer, surface water oxidation reactions were accelerated over NiFe-LDH/CoOx NP-TiO2 NRs. The charge transport process in NiFe-LDH/CoOx NP-TiO2 NRs photoanode-based PEC system was proposed in detail.


Subject(s)
Electrodes , Titanium , Wastewater , Titanium/chemistry , Wastewater/chemistry , Catalysis , Electrochemical Techniques/methods , Water Pollutants, Chemical/chemistry , Hydroxides/chemistry , Waste Disposal, Fluid/methods , Photochemical Processes , Nanotubes/chemistry , Coloring Agents/chemistry , Azo Compounds/chemistry , Water Purification/methods , Disinfection/methods
2.
Chemosphere ; 360: 142450, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38801902

ABSTRACT

Herein, we successfully synthesized Hf/Zr co-doping on Fe2O3 nanorod photocatalyst by a hydrothermal process and quenching methods. The synergistic roles of Hf and Zr double-doping on the bacteria inactivation test and decomposition of organic pollutants were investigated in detail for the 1 wt% CoOx loaded Hf/Zr-Fe2O3 NRs and CuOx/CoOx loaded Hf/Zr-Fe2O3 NRs photocatalyst. Initially, the rod-like porous morphology of the Hf/Zr-doped Fe2O3 NRs was produced via a hydrothermal method at various Hf co-doping (0, 2, 4, 7 and 10)%. Further, CoOx and CuOx loaded by a wet impregnation approach on the Hf/Zr-Fe2O3 NRs and a highly photoactive Hf(4)/Zr-Fe2O3 [CoOx/CuOx] NRs photocatalyst were developed. After the Hf(4)/Zr-Fe2O3 [CoOx/CuOx] NRs photocatalyst treatment, the Bio-TEM imagery of bacterial cells showed extensive morphological deviations in cell membranes. Hf(4)/Zr-Fe2O3 NR achieved 84.1% orange II degradation upon 3 h illumination, which is higher than that of Hf-Fe2O3 and Zr-Fe2O3 (68.7 and 73.5%, respectively). Additionally, the optimum sample, Hf(4)/Zr-Fe2O3 [CoOx/CuOx] photocatalyst, exhibited 95.5% orange II dye degradation after light radiation for 3 h. Optimized Hf(4)/Zr-Fe2O3 [CoOx/CuOx] catalysts exhibited 99.9% and 99.7% inactivation of E. coli and S. aureus with 120 min, respectively. Further, scavenger experiments revealed that the electrons are the primary responsible species for photocatalytic kinetics. This work will provide a rapid method for the development of high photocatalytic performance materials for bacterial disinfection and organic degradation.


Subject(s)
Anti-Bacterial Agents , Copper , Ferric Compounds , Nanotubes , Zirconium , Zirconium/chemistry , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Catalysis , Nanotubes/chemistry , Ferric Compounds/chemistry , Copper/chemistry , Copper/pharmacology , Hafnium/chemistry , Oxides/chemistry , Cobalt/chemistry , Photochemical Processes
3.
Int J Mol Sci ; 25(3)2024 Jan 29.
Article in English | MEDLINE | ID: mdl-38338917

ABSTRACT

Viruses have evolved sophisticated mechanisms to manipulate host cell processes and utilize intracellular organelles to facilitate their replication. These complex interactions between viruses and cellular organelles allow them to hijack the cellular machinery and impair homeostasis. Moreover, viral infection alters the cell membrane's structure and composition and induces vesicle formation to facilitate intracellular trafficking of viral components. However, the research focus has predominantly been on the immune response elicited by viruses, often overlooking the significant alterations that viruses induce in cellular organelles. Gaining a deeper understanding of these virus-induced cellular changes is crucial for elucidating the full life cycle of viruses and developing potent antiviral therapies. Exploring virus-induced cellular changes could substantially improve our understanding of viral infection mechanisms.


Subject(s)
Virus Diseases , Virus Replication , Humans , Organelles/ultrastructure , Host-Pathogen Interactions
4.
Micromachines (Basel) ; 15(1)2024 Jan 18.
Article in English | MEDLINE | ID: mdl-38258265

ABSTRACT

Free-form factor optoelectronics is becoming more important for various applications. Specifically, flexible and transparent optoelectronics offers the potential to be adopted in wearable devices in displays, solar cells, or biomedical applications. However, current transparent electrodes are limited in conductivity and flexibility. This study aims to address these challenges and explore potential solutions. For the next-generation transparent conductive electrode, Al-doped zinc oxide (AZO) and silver (AZO/Ag/AZO) deposited by in-line magnetron sputtering without thermal treatment was investigated, and this transparent electrode was used as a transparent organic light-emitting diode (OLED) anode to maximize the transparency characteristics. The experiment and simulation involved adjusting the thickness of Ag and AZO and OLED structure to enhance the transmittance and device performance. The AZO/Ag/AZO with Ag of 12 nm and AZO of 32 nm thickness achieved the results of the highest figure of merit (FOM) (Φ550 = 4.65 mΩ-1) and lowest roughness. The full structure of transparent OLED (TrOLED) with AZO/Ag/AZO anode and Mg:Ag cathode reached 64.84% transmittance at 550 nm, and 300 cd/m2 at about 4 V. The results demonstrate the feasibility of adopting flexible substrates, such as PET, without the need for thermal treatment. This research provides valuable insights into the development of transparent and flexible electronic devices.

5.
Sci Rep ; 14(1): 2309, 2024 01 28.
Article in English | MEDLINE | ID: mdl-38280903

ABSTRACT

Epithelial-mesenchymal transition (EMT) is the process by which epithelial cells acquire mesenchymal characteristics. This process induces cell migration and invasion, which are closely related to cancer metastasis and malignancy. EMT consists of various intermediate states that express both epithelial and mesenchymal traits, called partial EMT. Recently, several studies have focused on the roles of voltage-gated potassium (Kv) channels associated with EMT in cancer cell migration and invasion. In this study, we demonstrate the relationship between Kv3.4 and EMT and confirm the effects of cell migration and invasion. With TGF-ß treatment, EMT was induced and Kv3.4 was also increased in A549 cells, human lung carcinoma cells. The knockdown of Kv3.4 blocked the EMT progression reducing cell migration and invasion. However, the Kv3.4 overexpressed cells acquired mesenchymal characteristics and increased cell migration and invasion. The overexpression of Kv3.4 also has a synergistic effect with TGF-ß in promoting cell migration. Therefore, we conclude that Kv3.4 regulates cancer migration and invasion through TGF-ß-induced EMT and these results provide insights into the understanding of cancer metastasis.


Subject(s)
Lung Neoplasms , Transforming Growth Factor beta , Humans , A549 Cells , Transforming Growth Factor beta/pharmacology , Cell Line, Tumor , Transforming Growth Factor beta1/pharmacology , Lung Neoplasms/pathology , Epithelial-Mesenchymal Transition , Cell Movement
6.
Chemosphere ; 341: 140057, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37673185

ABSTRACT

In this study, in situ silver (Ag) - porous ZnO photocatalysts were synthesized via solvothermal and post-annealing treatment. The formation of the porous ZnO structure due to the removal of organic moieties from the inorganic-organic hybrids Ag-ZnS(en)0.5 during the annealing process. The optimal Ag-ZnO photocatalyst showed excellent photocatalytic degradation activity, with 95.5% orange II dye and 97.2% bisphenol A (BPA) degradation under visible light conditions. Additionally, the photocatalytic inactivation of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) led to a 97% inactivation rate after 2 h under dark conditions. Trapping experiments suggest that the superoxide anion (O2-) radicals are the main active species to degrade the organic dye. The improved photocatalytic dye degradation activity and inactivation of bacteria were attributed to the synergistic effect of Ag and porous ZnO structure, increased surface area, and efficiently separated the photoexcited charge carriers. This work could provide an effective strategy for the synthesis of porous structures toward organic pollutant degradation and bacterial inactivation in wastewater.


Subject(s)
Environmental Pollutants , Zinc Oxide , Escherichia coli , Porosity , Staphylococcus aureus , Bacteria
7.
Clin Exp Otorhinolaryngol ; 16(4): 317-325, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37536749

ABSTRACT

Conventional surgery through a transcervical incision is indicated for the treatment of certain tumors in the head and neck. However, this method can cause multiple problems, including scarring and cosmetic concerns. The endoscope-assisted hairline approach, which serves as an alternative to conventional surgical procedures, is gaining popularity due to its excellent cosmetic and functional outcomes. However, given the anatomical complexity involved, the endoscope-assisted hairline technique is not frequently employed in head and neck surgery. The evolution of the hairline surgical approach has been influenced by changes in disease conditions and recent advances in surgical tools. This review article discusses the use of endoscope-assisted hairline approaches in the resection of head and neck masses, focusing on the surgical procedure and postoperative clinical outcomes.

8.
Korean J Physiol Pharmacol ; 27(4): 417-426, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-37394239

ABSTRACT

The TRPM4 gene encodes a Ca2+-activated monovalent cation channel called transient receptor potential melastatin 4 (TRPM4) that is expressed in various tissues. Dysregulation or abnormal expression of TRPM4 has been linked to a range of diseases. We introduced the hemagglutinin (HA) tag into the extracellular S6 loop of TRPM4, resulting in an HA-tagged version called TRPM4-HA. This TRPM4-HA was developed to investigate the purification, localization, and function of TRPM4 in different physiological and pathological conditions. TRPM4-HA was successfully expressed in the intact cell membrane and exhibited similar electrophysiological properties, such as the current-voltage relationship, rapid desensitization, and current size, compared to the wild-type TRPM4. The presence of the TRPM4 inhibitor 9-phenanthrol did not affect these properties. Furthermore, a wound-healing assay showed that TRPM4-HA induced cell proliferation and migration, similar to the native TRPM4. Co-expression of protein tyrosine phosphatase, non-receptor type 6 (PTPN6 or SHP-1) with TRPM4-HA led to the translocation of TRPM4-HA to the cytosol. To investigate the interaction between PTPN6 and tyrosine residues of TRPM4 in enhancing channel activity, we generated four mutants in which tyrosine (Y) residues were substituted with phenylalanine (F) at the N-terminus of TRPM4. The YF mutants displayed properties and functions similar to TRPM4-HA, except for the Y256F mutant, which showed resistance to 9-phenanthrol, suggesting that Y256 may be involved in the binding site for 9-phenanthrol. Overall, the creation of HA-tagged TRPM4 provides researchers with a valuable tool to study the role of TRPM4 in different conditions and its potential interactions with other proteins, such as PTPN6.

9.
Chemosphere ; 337: 139255, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37356589

ABSTRACT

Hydrothermal and wet impregnation methods are presented in this study for synthesizing CoOx(1 wt%)/Sn/Zr-codoped Fe2O3 nanorod photocatalysts for the degradation of organic pollutants and deactivation of bacteria. A hydrothermal route was used to synthesize self-assembled rod-like hierarchical structures of Sn(0-6%) doped Zr-Fe2O3 NRs. Additionally, a wet impregnation method was used to load CoOx onto the surface of photocatalysts (Sn(0-6%)-doped Zr-Fe2O3 NRs). A series of 1 wt% CoOx modified Sn(0-6%)-doped Zr-Fe2O3 NRs were synthesized, characterized, and utilized for the photocatalytic decomposition of organic contaminants, along with the killing of E. coli and S. aureus. In comparison with 0, 2, and 6% Sn co-doped Zr-Fe2O3 NRs, the CoOx(1 wt%)/4%Sn/Zr-Fe2O3 NRs photocatalyst exhibited an E. coli and S. aureus inactivation efficiencies (90 and 98%). A bio-TEM study of treated and untreated bacterial cells revealed that the CoOx(1 wt%)/4%Sn/Zr-Fe2O3 NRs photocatalyst led to considerable changes in the bacterial cell membranes' morphology. The optimal CoOx(1 wt%)/Sn(4%) co-doped Zr-Fe2O3 NRs photocatalyst achieved degradation efficiencies of 98.5% and 94.6% for BPA and orange II dye, respectively. As a result, this work will provide a facile and effective method for developing visible light-active photocatalysts for bacterial inactivation and organic pollutants degradation.


Subject(s)
Escherichia coli , Nanotubes , Staphylococcus aureus , Catalysis , Light
10.
Article in English | MEDLINE | ID: mdl-32789791

ABSTRACT

The capacity of cells to organize complex biochemical reactions in intracellular space is a fundamental organizational principle of life. Key to this organization is the compartmentalization of the cytoplasm into distinct organelles, which is frequently achieved through intracellular membranes. Recent evidence, however, has added a new layer of flexibility to cellular compartmentalization. As such, in response to specific stimuli, liquid-liquid phase separations can lead to the rapid rearrangements of the cytoplasm to form membraneless organelles. Stress granules (SGs) are one such type of organelle that form specifically when cells are faced with stress stimuli, to aid cells in coping with stress. Inherently, altered SG formation has been linked to the pathogenesis of diseases associated with stress and inflammatory conditions, including cancer. Exciting discoveries have indicated an intimate link between SGs and tumorigenesis. Several pro-tumorigenic signaling molecules including the RAS oncogene, mTOR, and histone deacetylase 6 (HDAC6) have been shown to upregulate SG formation. Based on these studies, SGs have emerged as structures that can integrate oncogenic signaling and tumor-associated stress stimuli to enhance cancer cell fitness. In addition, growing evidence over the past decade suggests that SGs function not only to regulate the switch between survival and cell death, but also contribute to cancer cell proliferation, invasion, metastasis, and drug resistance. Although much remains to be learned about the role of SGs in tumorigenesis, these studies highlight SGs as a key regulatory hub in cancer and a promising therapeutic target.


Subject(s)
Cytoplasmic Granules , Neoplasms , Humans , Cytoplasmic Granules/metabolism , Cytoplasmic Granules/pathology , Stress Granules , Cytoplasm , Signal Transduction , Neoplasms/metabolism , Carcinogenesis/metabolism , Carcinogenesis/pathology
11.
Chem Commun (Camb) ; 59(2): 195-198, 2022 Dec 22.
Article in English | MEDLINE | ID: mdl-36477026

ABSTRACT

Hierarchical plasmonic nanostructures comprising gold nanorod (AuNR)-covered microballs via syringe-injection reduction show good potential for selective single-cell calcium ionophore (A23187) delivery and apoptosis induction in heterogenous cancer cells.


Subject(s)
Nanostructures , Nanotubes , Calcium Ionophores , Nanotubes/chemistry , Cell Line, Tumor , Gold/pharmacology , Gold/chemistry
12.
Acta Otolaryngol ; 142(9-12): 668-674, 2022.
Article in English | MEDLINE | ID: mdl-36384386

ABSTRACT

BACKGROUND: Although dizziness is a common symptom after vaccination, the mechanism, and prognosis are not well understood. AIMS/OBJECTIVES: This study aimed to investigate patients with dizziness after COVID-19 vaccination by analyzing objective information. METHODS: A retrospective study of patients who visited the outpatient clinics of two institutes with a complaint of dizziness occurring within 72 h after a COVID-19 vaccination. RESULTS: In most cases, patients experienced only a single event of dizziness, and the subjective symptom was relieved after a few weeks. All patients decreased gain of vestibular ocular reflex (VOR). The vestibular function test results showed signs of central vestibulopathy in some cases. We separated patients into two groups; the direction-fixed nystagmus (DFN) group and the direction-changing nystagmus (DCN) group. All patients showed decreased gain on the rotational chair test (RCT). The DFN group showed an 80% decrease in video head impulse test (vHIT) gain, whereas the DCN group only showed a decrease of 25%. In RCT, 66% of the DFN group showed asymmetry compared to 20% showing asymmetry in the DCN group. CONCLUSION AND SIGNIFICANCE: The patients who suffered from dizziness after the COVID-19 vaccination exhibited decreased VOR gain and in some cases signs of central vestibulopathy.


Subject(s)
COVID-19 , Nystagmus, Pathologic , Humans , Dizziness/diagnosis , Tertiary Care Centers , COVID-19/prevention & control , Vertigo/diagnosis , Vestibular Function Tests , Head Impulse Test/methods , Nystagmus, Pathologic/etiology , Nystagmus, Pathologic/diagnosis , Reflex, Vestibulo-Ocular
13.
Anal Chem ; 94(17): 6463-6472, 2022 05 03.
Article in English | MEDLINE | ID: mdl-35435669

ABSTRACT

Raman thermometry based on surface-enhanced Raman scattering has been developed using nanopipettes in cancer cell photothermal therapy (PTT). Gold nanorods (AuNRs) are robustly epoxied on glass pipettes with a high surface coverage of ∼95% and less than 10 nm-wide nanogaps for intracellular thermometry and photothermal cancer therapy. The temperature changes could be estimated from the N≡C band shifts of 4-fluorophenyl isocyanide (FPNC)-adsorbed AuNRs on the Raman thermometry nanopipette (RTN) surfaces. An intracellular temperature change of ∼2.7 °C produced by altering the [Ca2+] in A431 cells was detected using the RTN in vitro, as checked from fura-2 acetoxymethyl ester (fura-2 AM) fluorescence images. For in vivo experiments, local temperature rises of ∼19.2 °C were observed in the mouse skin, whereas infrared camera images could not tract due to spatial resolution. In addition, a tumor growth suppression was observed in the PTT processes after an administration of the three AuNR-coated nanopipettes combined with a 671 nm laser irradiation for 5 min in 30 days. These results demonstrate not only the localized temperature sensing ability of FPNC-tagged AuNR nanopipettes in cell biology but also anti-cancer effects in photothermal cancer therapy.


Subject(s)
Nanotubes , Neoplasms , Thermometry , Animals , Cell Line, Tumor , Fura-2 , Gold , Mice , Neoplasms/diagnostic imaging , Neoplasms/pathology , Neoplasms/therapy , Photothermal Therapy
14.
BMB Rep ; 54(12): 620-625, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34814975

ABSTRACT

Microglia are known to be activated in the hypothalamic paraventricular nucleus (PVN) of rats with cardiovascular diseases. However, the exact role of microglial activation in the plasticity of presympathetic PVN neurons associated with the modulation of sympathetic outflow remains poorly investigated. In this study, we analyzed the direct link between microglial activation and spontaneous firing rate along with the underlying synaptic mechanisms in PVN neurons projecting to the rostral ventrolateral medulla (RVLM). Systemic injection of LPS induced microglial activation in the PVN, increased the frequency of spontaneous firing activity of PVN-RVLM neurons, reduced GABAergic inputs into these neurons, and increased plasma NE levels and heart rate. Systemic minocycline injection blocked all the observed LPS-induced effects. Our results indicate that LPS increases the firing rate and decreases GABAergic transmission in PVN-RVLM neurons associated with sympathetic outflow and the alteration is largely attributed to the activation of microglia. Our findings provide some insights into the role of microglial activation in regulating the activity of PVN-RVLM neurons associated with modulation of sympathetic outflow in cardiovascular diseases. [BMB Reports 2021; 54(12): 620-625].


Subject(s)
Microglia , Paraventricular Hypothalamic Nucleus , Animals , Lipopolysaccharides/pharmacology , Neural Pathways/physiology , Neurons , Paraventricular Hypothalamic Nucleus/physiology , Rats , Rats, Sprague-Dawley
15.
Biochem Biophys Res Commun ; 551: 140-147, 2021 04 30.
Article in English | MEDLINE | ID: mdl-33740620

ABSTRACT

Cell migration is a complex and important process in cancer progression. Vimentin has pivotal roles in cancer cell migration, and various signaling pathways including the AKT pathway are involved in cancer cell migration via vimentin regulation. Recent studies have revealed that voltage-gated potassium (Kv) channels have important functions in cancer cell migration; however, the exact mechanism is still unclear. In the present study, we focused on Kv3 channels with vimentin in cancer migration using human cervical cancer cells (HeLa) and canine mammary tumor cells (CHMp). Cancer cell migration was significantly inhibited, and vimentin expression was significantly decreased by Kv3 blocker, BDS-II. The Kv3 blocker also inactivated the AKT pathway in HeLa cells. In addition, reduced expressions of vimentin and Kv3.4 were observed in HeLa cells when treated with AKT blocker, MK2206. These results suggest that Kv3 channels play important roles in cancer cell migration by regulating vimentin and having closely related with the AKT pathway in human cervical cancer cells.


Subject(s)
Cell Movement , Neoplasms/metabolism , Neoplasms/pathology , Shaw Potassium Channels/metabolism , Vimentin/metabolism , Animals , Cell Line , Cell Movement/drug effects , Dogs , HeLa Cells , Humans , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Proto-Oncogene Proteins c-akt/metabolism , Shaw Potassium Channels/antagonists & inhibitors , Vimentin/biosynthesis
16.
BMB Rep ; 54(2): 130-135, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33407994

ABSTRACT

Voltage-gated potassium (Kv) channels are involved in many important cellular functions and play pivotal roles in cancer progression. The expression level of Kv2.1 was observed to be higher in the highly metastatic prostate cancer cells (PC-3), specifically in their membrane, than in immortalized prostate cells (WPMY-1 cells) and comparatively less metastatic prostate cancer cells (LNCaP and DU145 cells). However, Kv2.1 expression was significantly decreased when the cells were treated with antioxidants, such as N-acetylcysteine or ascorbic acid, implying that the highly expressed Kv2.1 could detect reactive oxygen species (ROS) in malignant prostate cancer cells. In addition, the blockade of Kv2.1 with stromatoxin-1 or siRNA targeting Kv2.1 significantly inhibited the migration of malignant prostate cancer cells. Our results suggested that Kv2.1 plays an important role as a ROS sensor and that it is a promising therapeutic molecular target in metastasis of prostate cancer. [BMB Reports 2021; 54(2): 130-135].


Subject(s)
Prostatic Neoplasms/metabolism , Shab Potassium Channels/metabolism , Cell Line , Cell Movement/drug effects , Humans , Male , PC-3 Cells , Prostatic Neoplasms/pathology , RNA, Messenger/antagonists & inhibitors , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Small Interfering/pharmacology , Shab Potassium Channels/antagonists & inhibitors , Shab Potassium Channels/genetics
17.
Biochem Biophys Res Commun ; 533(4): 1255-1261, 2020 12 17.
Article in English | MEDLINE | ID: mdl-33066958

ABSTRACT

Oxidative stress is one of the most important risk factors for cataractogenesis. Previous studies have indicated that BDS-II, a Kv3 channel blocker, plays pivotal roles in oxidative stress-related diseases. This study demonstrates that BDS-II exerts a protective effect on cataractogenesis. Specifically, BDS-II was observed to inhibit lens opacity induced by H2O2. BDS-II was also determined to inhibit cataract progression in a sodium selenite-induced in vivo cataract model by inhibiting reduction of the total GSH. In addition, BDS-II was demonstrated to protect human lens epithelial cells against H2O2-induced cell death. Our results suggest that BDS-II is a potential pharmacological candidate in cataract therapy.


Subject(s)
Cataract/prevention & control , Oxidative Stress/drug effects , Potassium Channel Blockers/therapeutic use , Shaw Potassium Channels/antagonists & inhibitors , Animals , Cell Death , Cell Line , Disease Progression , Epithelial Cells/drug effects , Female , Humans , Lens, Crystalline/cytology , Male , Potassium Channel Blockers/pharmacology , Rats, Sprague-Dawley , Shaw Potassium Channels/metabolism
18.
Angew Chem Int Ed Engl ; 58(9): 2710-2714, 2019 02 25.
Article in English | MEDLINE | ID: mdl-30600872

ABSTRACT

Multiple sharp-edged gold nanostars were efficiently assembled on nanopipette tips through electrostatic interactions for use as a potent intracellular hypoxia-sensing Raman probe. Colloidal stability and surface immobilization were checked using scanning electron microscopy, light scattering, and zeta potential measurements. Site-specific intracellular hypoxia levels can be estimated in vitro and in vivo using Raman lancets (RL). Distinct Raman spectral changes for the nitro-(NO2 ) functional group of the redox marker 4-nitrothiophenol (4NTP) can be quantified according to the intracellular oxygen (O2 ) content, ranging from 1 % to 10 %. Redox potential changes in mitochondrial respiration were also examined through serial injections of inhibitors. 3D-cultured cells and in vivo tests were used to validate our method, and its application in the assessment of the aggressiveness of cancer cells by differentiating spectral changes between malignant and benign cells was demonstrated.


Subject(s)
Breast Neoplasms/diagnostic imaging , Cell Hypoxia , Molecular Probes/chemistry , Nanoparticles/chemistry , Oxygen/analysis , Single-Cell Analysis , Animals , Cells, Cultured , Female , Humans , Injections, Subcutaneous , Mice , Molecular Probes/administration & dosage , Optical Imaging , Oxidation-Reduction , Particle Size , Spectrum Analysis, Raman , Surface Properties
19.
Int J Mol Sci ; 19(4)2018 Apr 02.
Article in English | MEDLINE | ID: mdl-29614836

ABSTRACT

Voltage-gated potassium (Kv) channels, including Kv3.1 and Kv3.4, are known as oxygen sensors, and their function in hypoxia has been well investigated. However, the relationship between Kv channels and tumor hypoxia has yet to be investigated. This study demonstrates that Kv3.1 and Kv3.4 are tumor hypoxia-related Kv channels involved in cancer cell migration and invasion. Kv3.1 and Kv3.4 protein expression in A549 and MDA-MB-231 cells increased in a cell density-dependent manner, and the pattern was similar to the expression patterns of hypoxia-inducible factor-1α (HIF-1α) and reactive oxygen species (ROS) according to cell density, whereas Kv3.3 protein expression did not change in A549 cells with an increase in cell density. The Kv3.1 and Kv3.4 blocker blood depressing substance (BDS) did not affect cell proliferation; instead, BDS inhibited cell migration and invasion. We found that BDS inhibited intracellular pH regulation and extracellular signal-regulated kinase (ERK) activation in A549 cells cultured at a high density, potentially resulting in BDS-induced inhibition of cell migration and invasion. Our data suggest that Kv3.1 and Kv3.4 might be new therapeutic targets for cancer metastasis.


Subject(s)
Shaw Potassium Channels/metabolism , A549 Cells , Cell Line, Tumor , Cell Movement/drug effects , HT29 Cells , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Potassium Channel Blockers/pharmacology , Reactive Oxygen Species/metabolism
20.
Sci Rep ; 7(1): 2075, 2017 05 18.
Article in English | MEDLINE | ID: mdl-28522852

ABSTRACT

The Kv3.4 channel is characterized by fast inactivation and sensitivity to oxidation. However, the physiological role of Kv3.4 as an oxidation-sensitive channel has yet to be investigated. Here, we demonstrate that Kv3.4 plays a pivotal role in oxidative stress-related neural cell damage as an oxidation-sensitive channel and that HIF-1α down-regulates Kv3.4 function, providing neuroprotection. MPP+ and CoCl2 are reactive oxygen species (ROS)-generating reagents that induce oxidative stress. However, only CoCl2 decreases the expression and function of Kv3.4. HIF-1α, which accumulates in response to CoCl2 treatment, is a key factor in Kv3.4 regulation. In particular, mitochondrial Kv3.4 was more sensitive to CoCl2. Blocking Kv3.4 function using BDS-II, a Kv3.4-specific inhibitor, protected SH-SY5Y cells against MPP+-induced neural cell death. Kv3.4 inhibition blocked MPP+-induced cytochrome c release from the mitochondrial intermembrane space to the cytosol and mitochondrial membrane potential depolarization, which are characteristic features of apoptosis. Our results highlight Kv3.4 as a possible new therapeutic paradigm for oxidative stress-related diseases, including Parkinson's disease.


Subject(s)
Apoptosis , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Neurons/metabolism , Oxidative Stress , Shaw Potassium Channels/metabolism , 1-Methyl-4-phenylpyridinium/toxicity , Cell Line, Tumor , Cobalt/toxicity , Humans , Neurons/drug effects , Potassium Channel Blockers/pharmacology , Shaw Potassium Channels/antagonists & inhibitors
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