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1.
Front Immunol ; 15: 1369326, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38953022

RESUMEN

Objectives: Mast cell (MC) degranulation is a key process in allergic reactions and inflammatory responses. Aspartate aminotransferase 1 (AAT1)-derived endogenous sulfur dioxide (SO2) is an important regulator of MC function. However, the mechanism underlying its role in MC degranulation remains unclear. This study aimed to investigate the mechanism by which endogenous SO2 controlled MC degranulation. Methods: HMC-1 and Rat basophilic leukemia cell MC line (RBL-2H3) were used in the cell experiments. SO2 content was detected by in situ fluorescent probe. MC degranulation represented by the release rate of MC ß-hexosaminidase was determined using a colorimetric assay. Sulfenylation of galectin-9 (Gal-9) in MCs and purified protein was detected using a biotin switch assay. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to determine the exact sulfenylation sites of Gal-9 by SO2. Animal models of passive cutaneous anaphylaxis (PCA) and hypoxia-driven pulmonary vascular remodeling were used to investigate the effect of SO2 on mast cell activation in vivo. Site-directed mutation of Gal-9 was conducted to confirm the exact site of SO2 and support the significance of SO2/Gal-9 signal axis in the regulation of MC degranulation. Results: Degranulation was increased in AAT1-knockdowned MCs, and SO2 supplementation reversed the increase in MC degranulation. Furthermore, deficiency of endogenous SO2 contributed to IgE-mediated degranulation in vitro. Besides, SO2 inhibited IgE-mediated and hypoxia-driven MC degranulation in vivo. Mechanistically, LC-MS/MS analysis and site-directed mutation results showed that SO2 sulfenylated Gal-9 at cysteine 74. Sulfenylation of the 74th cysteine of Gal-9 protein was required in the SO2-inhibited MC degranulation under both physiological and pathophysiological conditions. Conclusion: These findings elucidated that SO2 inhibited MC degranulation via sulfenylating Gal-9 under both physiological and pathophysiological conditions, which might provide a novel treatment approach for MC activation-related diseases.


Asunto(s)
Degranulación de la Célula , Cisteína , Galectinas , Mastocitos , Dióxido de Azufre , Animales , Degranulación de la Célula/efectos de los fármacos , Mastocitos/metabolismo , Mastocitos/inmunología , Mastocitos/efectos de los fármacos , Cisteína/metabolismo , Ratas , Dióxido de Azufre/farmacología , Dióxido de Azufre/metabolismo , Humanos , Galectinas/metabolismo , Ratones , Masculino , Anafilaxis Cutánea Pasiva , Línea Celular
2.
Zool Res ; 45(4): 857-874, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39004863

RESUMEN

Emerging evidence indicates that sleep deprivation (SD) can lead to Alzheimer's disease (AD)-related pathological changes and cognitive decline. However, the underlying mechanisms remain obscure. In the present study, we identified the existence of a microbiota-gut-brain axis in cognitive deficits resulting from chronic SD and revealed a potential pathway by which gut microbiota affects cognitive functioning in chronic SD. Our findings demonstrated that chronic SD in mice not only led to cognitive decline but also induced gut microbiota dysbiosis, elevated NLRP3 inflammasome expression, GSK-3ß activation, autophagy dysfunction, and tau hyperphosphorylation in the hippocampus. Colonization with the "SD microbiota" replicated the pathological and behavioral abnormalities observed in chronic sleep-deprived mice. Remarkably, both the deletion of NLRP3 in NLRP3 -/- mice and specific knockdown of NLRP3 in the hippocampus restored autophagic flux, suppressed tau hyperphosphorylation, and ameliorated cognitive deficits induced by chronic SD, while GSK-3ß activity was not regulated by the NLRP3 inflammasome in chronic SD. Notably, deletion of NLRP3 reversed NLRP3 inflammasome activation, autophagy deficits, and tau hyperphosphorylation induced by GSK-3ß activation in primary hippocampal neurons, suggesting that GSK-3ß, as a regulator of NLRP3-mediated autophagy dysfunction, plays a significant role in promoting tau hyperphosphorylation. Thus, gut microbiota dysbiosis was identified as a contributor to chronic SD-induced tau pathology via NLRP3-mediated autophagy dysfunction, ultimately leading to cognitive deficits. Overall, these findings highlight GSK-3ß as a regulator of NLRP3-mediated autophagy dysfunction, playing a critical role in promoting tau hyperphosphorylation.


Asunto(s)
Autofagia , Disbiosis , Microbioma Gastrointestinal , Proteína con Dominio Pirina 3 de la Familia NLR , Privación de Sueño , Proteínas tau , Animales , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Microbioma Gastrointestinal/fisiología , Privación de Sueño/metabolismo , Privación de Sueño/fisiopatología , Privación de Sueño/complicaciones , Ratones , Autofagia/fisiología , Proteínas tau/metabolismo , Proteínas tau/genética , Masculino , Hipocampo/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Inflamasomas/metabolismo
3.
Zhongguo Zhong Yao Za Zhi ; 49(11): 2940-2946, 2024 Jun.
Artículo en Chino | MEDLINE | ID: mdl-39041153

RESUMEN

The chemical constituents from Leucas ciliata belonging to Leucas genus in Lamiaceae were systematically explored by silica gel column chromatography, ODS column chromatography, Sephadex LH-20 gel column chromatography, and preparative high performance liquid chromatography, and seventeen phenolic acids were isolated. The chemical structures of the compounds were identified by their physicochemical properties, spectroscopic data, and literature. They were 4-hydroxyphenethyl ethyl succinate(1), 4-hydroxyphenethyl methyl succinate(2), 2-(4-hydroxyphenyl) ethyl acetate(3), p-hydroxyphenylethyl anisate(4), cassia cis-trans diphenylpropanoid(5), p-coumaric acid(6), 3,4-dihydroxybenzenepropionic acid methyl ester(7), caffeic acid(8), trans-p-hydroxyl ethyl cinnamate(9), methyl p-hydroxybenzeneacetate(10), 4-hydroxyphenethyl alcohol(11), syringic acid(12), vanillin(13), protocatechuic acid(14), salicylic acid(15), p-hydroxybenzaldehyde(16), and diorcinol(17). Among them, compound 1 was new, and compounds 2-10, 12, 14, and 16-17 were isolated from the plants belonging to Leucas genus for the first time. All compounds were obtained from L. ciliata for the first time. The anti-inflammatory activity of compounds 1-17 on NO production in lipopolysaccharide(LPS)-induced mouse leukemia cells of monocyte macrophage(RAW264. 7) cells was evaluated. The results showed that compounds 5, 7, and 9 exhibited significant anti-inflammatory activity, with IC50values of(10. 14±0. 36)-(21. 17±0. 11) µmol·L~(-1).


Asunto(s)
Antiinflamatorios , Hidroxibenzoatos , Antiinflamatorios/farmacología , Antiinflamatorios/química , Hidroxibenzoatos/química , Hidroxibenzoatos/farmacología , Animales , Ratones , Células RAW 264.7 , Lamiaceae/química , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Estructura Molecular , Óxido Nítrico , Macrófagos/efectos de los fármacos
4.
Opt Lett ; 49(12): 3300-3303, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38875605

RESUMEN

Optical path length (OPL) noise resulting from stray light significantly constrains interferometry displacement measurements in the low-frequency band. This paper presents an analytical model considering the presence of stray light in heterodyne laser interferometers. Due to the cyclic nonlinear coupling effect, there will be some special OPLs of stray light, minimizing the frequency-mixing impact to zero. Consequently, we propose a noise suppression scheme that locks the OPL of stray light at the zero coupling point. Therefore, we significantly enhanced the interference displacement measurement noise within the low-frequency band. Experimental results show that the interferometer achieves a displacement noise level lower than 6 pm/Hz1/2 covering 1 mHz.

5.
Spine J ; 2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38914373

RESUMEN

BACKGROUND CONTEXT: Large annulus fibrosus (AF) defects often lead to a high rate of reherniation, particularly in the medial AF region, which has limited self-healing capabilities. The increasing prevalence of herniated discs underscores the need for effective repair strategies. PURPOSE: The objectives of this study were to design an AF repair technique to reduce solve the current problems of insufficient mechanical properties and poor sealing capacity. STUDY DESIGN: In vitro biomechanical experiments and finite element analysis. METHODS: The materials used in this study were patches and hydrogels with good biocompatibility and sufficient mechanical properties to withstand loading in the lumbar spine. Five repair techniques were assessed in this study: hydrogel filler (HF), AF patch medial barrier (MB), AF patch medial barrier and hydrogel filler (MB&HF), AF patch medial-lateral barrier (MLB), and AF patch medial-lateral barrier and hydrogel filler (MLB&HF). The repair techniques were subjected to in vitro testing (400 N axial compression and 0-500 N fatigue loading at 5Hz) and finite element analysis (400 N axial compression) to evaluate the effectiveness at repairing large AF defects. The evaluation included repair tightness, spinal stability, and fatigue resistance. RESULTS: From the in vitro testing, the failure load of the repair techniques was in the following order HF MLB >MB&HF >MLB&HF. CONCLUSIONS: The combined use of patches and hydrogels exhibited promising mechanical properties postdiscectomy, providing a promising solution for addressing large AF defects and improving disc stability. CLINICAL SIGNIFICANCE: This study introduces a promising method for repairing large annular fissure (AF) defects after disc herniation, combining patch repair with a hydrogel filler. These techniques hold potential for developing clinical AF repair products to address this challenging issue.

6.
Acta Biomater ; 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38909721

RESUMEN

Bacterial pneumonia is a common disease with significant health risks. However, the overuse antibiotics in clinics face challenges such as inadequate targeting and limited drug utilization, leading to drug resistance and gut dysbiosis. Herein, a dual-responsive lung inflammatory tissue targeted nanoparticle (LITTN), designed for targeting lung tissue and bacteria, is screened from a series of prepared nanoparticles consisting of permanent cationic lipids, acid-responsive lipids, and reactive oxygen species-responsive and phenylboronic acid-modified lipids with different surface properties. Such nanoparticle is further verified to enhance the adsorption of vitronectin in serum. Additionally, the optimized nanoparticle exhibits more positive charge and coordination of boric acid with cis-diol in the infected microenvironment, facilitating electrostatic interactions with bacteria and biofilm penetration. Importantly, the antibacterial efficiency of dual-responsive rifampicin-loaded LITTN (Rif@LITTN) against methicillin-resistant staphylococcus aureus is 10 times higher than that of free rifampicin. In a mouse model of bacterial pneumonia, the intravenous administration of Rif@LITTN could precisely target the lungs, localize in the lung infection microenvironment, and trigger the responsive release of rifampicin, thereby effectively alleviating lung inflammation and reducing damage. Notably, the targeted delivery of rifampicin helps protect against antibiotic-induced changes in the gut microbiota. This study establishes a new strategy for precise delivery to the lung-infected microenvironment, promoting treatment efficacy while minimizing the impact on gut microbiota. STATEMENT OF SIGNIFICANCE: Intravenous antibiotics play a critical role in clinical care, particularly for severe bacterial pneumonia. However, the inability of antibiotics to reach target tissues causes serious side effects, including liver and kidney damage and intestinal dysbiosis. Therefore, achieving precise delivery of antibiotics is of great significance. In this study, we developed a novel lung inflammatory tissue-targeted nanoparticle that could target lung tissue after intravenous administration and then target the inflammatory microenvironment to trigger dual-responsive antibiotics release to synergistically treat pneumonia while maintaining the balance of gut microbiota and reducing the adverse effects of antibiotics. This study provides new ideas for targeted drug delivery and reference for clinical treatment of pneumonia.

7.
Neurosci Bull ; 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38819707

RESUMEN

Knowledge about the neuronal dynamics and the projectome are both essential for understanding how the neuronal network functions in concert. However, it remains challenging to obtain the neural activity and the brain-wide projectome for the same neurons, especially for neurons in subcortical brain regions. Here, by combining in vivo microscopy and high-definition fluorescence micro-optical sectioning tomography, we have developed strategies for mapping the brain-wide projectome of functionally relevant neurons in the somatosensory cortex, the dorsal hippocampus, and the substantia nigra pars compacta. More importantly, we also developed a strategy to achieve acquiring the neural dynamic and brain-wide projectome of the molecularly defined neuronal subtype. The strategies developed in this study solved the essential problem of linking brain-wide projectome to neuronal dynamics for neurons in subcortical structures and provided valuable approaches for understanding how the brain is functionally organized via intricate connectivity patterns.

8.
Phytochemistry ; 223: 114139, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38750707

RESUMEN

Eleven undescribed isoquinoline alkaloids (1-8, 14, 15, and 24), along with 19 analogues (9-13, 16-23, and 25-30) were isolated from the barks of Alangium salviifolium. The structures of the undescribed compounds were elucidated through the analysis of their HR-ESI-MS, 1D and 2D NMR, IR, UV, and X-ray diffraction. The absolute configuration of 8 was established via the ECD calculation. Notably, compounds 1/2 and 3/4 were two pairs of C-14 epimers. The isolated alkaloids were evaluated for their cytotoxicity against various cancer cell lines, including SGC-7901, HeLa, K562, A549, BEL-7402, HepG2, and B16, ß-carboline-benzoquinolizidine (14-22) and cepheline-type (24-28) alkaloids exhibited remarkable cytotoxicity, with IC50 values ranging from 0.01 to 48.12 µM. Remarkably, compounds 17 and 21 demonstrated greater cytotoxicity than the positive control doxorubicin hydrochloride. Furthermore, a significant proportion of these bioactive alkaloids possess a C-1' epimer configuration. The exploration of their structure-activity relationship holds promise for directing future investigations into alkaloids derived from Alangium, potentially leading to novel insights and therapeutic advancements.


Asunto(s)
Alcaloides , Antineoplásicos Fitogénicos , Ensayos de Selección de Medicamentos Antitumorales , Isoquinolinas , Corteza de la Planta , Humanos , Alcaloides/química , Alcaloides/farmacología , Alcaloides/aislamiento & purificación , Corteza de la Planta/química , Isoquinolinas/química , Isoquinolinas/farmacología , Isoquinolinas/aislamiento & purificación , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Estructura Molecular , Relación Estructura-Actividad , Línea Celular Tumoral , Alangiaceae/química , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga
9.
Int J Biol Macromol ; 270(Pt 2): 132181, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38740155

RESUMEN

Nowadays, developing vascular grafts (e.g., vascular patches and tubular grafts) is challenging. Bacterial cellulose (BC) with 3D fibrous network has been widely investigated for vascular applications. In this work, different from BC vascular patch cultured with the routine culture medium, dopamine (DA)-containing culture medium is employed to in situ synthesize dense BC fibrous structure with significantly increased fiber diameter and density. Simultaneously, BC fibers are modified by DA during in situ synthesis process. Then DA on BC fibers can self-polymerize into polydopamine (PDA) accompanied with the removal of bacteria in NaOH solution, obtaining PDA-modified dense BC (PDBC) vascular patch. Heparin (Hep) is subsequently covalently immobilized on PDBC fibers to form Hep-immobilized PDBC (Hep@PDBC) vascular patch. The obtained results indicate that Hep@PDBC vascular patch exhibits remarkable tensile and burst strength due to its dense fibrous structure. More importantly, compared with BC and PDBC vascular patches, Hep@PDBC vascular patch not only displays reduced platelet adhesion and improved anticoagulation activity, but also promotes the proliferation, adhesion, spreading, and protein expression of human umbilical vein endothelial cells, contributing to the endothelialization process. The combined strategy of in situ densification and Hep immobilization provides a feasible guidance for the construction of BC-based vascular patches.


Asunto(s)
Prótesis Vascular , Celulosa , Heparina , Células Endoteliales de la Vena Umbilical Humana , Celulosa/química , Heparina/química , Heparina/farmacología , Humanos , Adhesividad Plaquetaria/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Polímeros/química , Polímeros/farmacología , Indoles/química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología
10.
Front Cardiovasc Med ; 11: 1273666, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38590695

RESUMEN

Background: The relationship between gut microbiota composition and coronary heart disease (CHD) has been recently reported in several observational studies. However, the causal effect of gut microbiota on coronary heart disease is uncharted. Objective: This study attempted to investigate the effect of gut microbiota on coronary heart disease by Mendelian randomization (MR) analysis. Methods: Through the two-sample MR method, single-nucleotide polymorphisms relevant to gut microbiota were selected as instrument variables to evaluate the causal association between gut microbiota and the risk of CHD. Results: According to the selection criteria of the inverse variance-weighted average method, Class Actinobacteria, Class Lentisphaeria, Family Clostridiales vadinBB60group, Genus Clostridium innocuum group, Genus Bifidobacterium, Genus Butyricicoccus, Genus Oxalobacter, Genus Turicibacter, and Order Victivallales, presented a suggestive association with coronary heart disease. Conclusion: This two-sample Mendelian randomization study found that gut microbiota was causally associated with coronary heart disease. Further randomized controlled trials are needed to clarify the protective effect of probiotics on coronary heart disease and their specific protective mechanisms.

11.
Inorg Chem ; 63(17): 7746-7753, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38609344

RESUMEN

A novel two-dimensional (2D) Hofmann-type coordination polymer, {FeII(PyHbim)2[Pd(CN)4]}·2CH3OH [1·2CH3OH, PyHbim = 2-(4-pyridyl)benzimidazole], has been synthesized, which can undergo a spontaneous guest exchange, transforming to 1·2H2O in a single-crystal-to-single-crystal (SCSC) manner, shifting from orthorhombic Cmmm to monoclinic C2/m involving the displacement of 2D layers. The solvent-induced SCSC transformation process was reversible and verified through powder X-ray diffraction (PXRD) and single-crystal X-ray crystallography analyses. Both 1·2CH3OH and 1·2H2O exhibit complete and abrupt spin crossover (SCO) behaviors in two steps, while their SCO temperature ranges drastically shift by ca.100 K, spanning room temperature, owing to different intermolecular interactions resulting from diverse interlayer packing manners and host-guest interactions. Besides, a structural phase transition is observed in 1·2CH3OH, contributing to the two-step spin transition.

12.
Oncol Lett ; 27(4): 148, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38385116

RESUMEN

Occult urothelial carcinoma (UC), particularly with mediastinal metastases, is an uncommon clinical occurrence. The present study describes the unusual case of a 70-year-old male patient who developed mediastinal metastases from an occult UC. Histological evaluations and immunohistochemical features of the mediastinal tumor were indicative of UC; however, extensive imaging failed to identify the primary urological lesion. The findings suggest that mediastinal metastases from UCs, despite their rarity, should be considered in cases where patients with mediastinal tumors exhibit chest-related symptoms. Prompt pathological examinations are crucial for ascertaining the nature and origin of the tumor. Moreover, individualized treatment should be performed in strict accordance with the established oncology guidelines.

13.
Chemistry ; 30(24): e202303912, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38319524

RESUMEN

Adsorption of metal-organic complexes on metallic surfaces to produce well-defined single site catalysts is a novel approach combining the advantages of homogeneous and heterogeneous catalysis. To avoid the "surface trans-effect" a dome-shaped molybdenum(0) tricarbonyl complex supported by an tolylazacalix[3](2,6)pyridine ligand is synthesized. This vacuum-evaporable complex both activates CO and reacts with molecular oxygen (O2) to form a Mo(VI) trioxo complex which in turn is capable of catalytically mediating oxygen transfer. The molybdenum tricarbonyl- and trioxo complexes are investigated in the solid state, in homogeneous solution and on noble metal surfaces (Cu, Au) employing a range of spectroscopic and analytical methods.

14.
Int J Biol Macromol ; 261(Pt 2): 129834, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38302029

RESUMEN

The unique stere-complex crystal formed by poly(ʟ-lactide)/poly(ᴅ-lactide) (PLLA/PDLA) has a significant impact on properties of poly-lactide materials and is considered an effective means to improve the barrier properties of poly-lactide (PLA). In this work, poly-lactide films with different aggregate structures were prepared and the relationship of aggregate structure and barrier properties were explored. The results show that the crystal structure including crystallinity and crystal forms can be controlled by adjusting the isothermal crystallization time and crystallization temperature during the molding process. PLLA/PDLA composite films contain both homochiral crystallites and stereo-complex crystallites, and there is a synergistic crystallization effect between the two of them, which provides the composite films with high crystallinity and excellent barrier properties. Compared to the PLLA with homochiral crystallites, the PLLA/PDLA composite film with only stereo-complex crystallites exhibits higher barrier properties. The linear correlation between the crystallinity and the barrier properties is weak due to the changes in crystallization behavior and then the structure of poly-lactide caused by stereo-complexation. The linear correlation between the crystallinity and the barrier properties of the blend film is strong in the low crystallinity but weak at high crystallinity. Compared to homochiral crystallites, stereo-complex crystallites exhibits lower crystallinity dependence. It has been proven that different crystal forms have different design ideas for preparing high-barrier films, but the stereo-complexation resulting from the intermolecular forces between PLLA and PDLA having complementary chemical structure, is an effective method for enhancing the barrier performances of poly-lactide sustainably.


Asunto(s)
Dioxanos , Poliésteres , Cristalización , Poliésteres/química
15.
Bioinformatics ; 40(2)2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38291952

RESUMEN

MOTIVATION: Spectral imaging is often used to observe different objects with multiple fluorescent labels to reveal the development of the biological event. As the number of observed objects increases, the spectral overlap between fluorophores becomes more serious, and obtaining a "pure" picture of each fluorophore becomes a major challenge. Here, we propose a blind spectral unmixing algorithm called BINGO (Blind unmixing via SVD-based Initialization Nmf with project Gradient descent and spare cOnstrain), which can extract all kinds of fluorophores more accurately from highly overlapping multichannel data, even if the spectra of the fluorophores are extremely similar or their fluorescence intensity varies greatly. RESULTS: BINGO can isolate up to 10 fluorophores from spectral imaging data for a single excitation. nine-color living HeLa cells were visualized distinctly with BINGO. It provides an important algorithmic tool for multiplex imaging studies, especially in intravital imaging. BINGO shows great potential in multicolor imaging for biomedical sciences. AVAILABILITY AND IMPLEMENTATION: The source code used for this paper is available with the test data at https://github.com/Xinyuan555/BINGO_unmixing.


Asunto(s)
Algoritmos , Programas Informáticos , Humanos , Microscopía Fluorescente/métodos , Células HeLa , Colorantes Fluorescentes
16.
Chemphyschem ; 25(5): e202300693, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38183359

RESUMEN

Lithium-sulfur batteries (LSBs) are considered as the development direction of the new generation energy storage system due to their high energy density and low cost. The slow redox kinetics of sulfur and the shuttle effect of lithium polysulfide (LiPS) are considered to be the main obstacles to the practical application of LSBs. Transition-metal sulfide as the cathode host can improve the Li-S redox chemistry. However, there has been no investigation of the application of FeS2 host in Li-S redox chemistry. Applying the first-principles calculations, we investigated the formation energy, band gap, Li+ diffusion, adsorption energy, catalytic performance and Li2 S decomposition barrier of FeAx S2-x (A=N, P, O, Se; x=0, 0.125, 0.25, 0.375) to explore the Li-S redox chemistry and finally select excellent host material. FeA0.25 S1.75 (A=P, Se) has a low Li+ diffusion barrier and superior electronic conductivity. FeO0.25 S1.75 is more favorable for LiPS adsorption, followed by FeP0.25 S1.75 . FeP0.25 S1.75 (001) shows a low overpotential for the Li-S redox chemistry. In summary, FeP0.25 S1.75 has more application potential in LSBs due to its physical and chemical properties, followed by FeSe0.25 S1.75 . This work provides theoretical guidance for the design and selection of the sulfur cathode host materials in LSBs.

17.
Phys Chem Chem Phys ; 26(3): 2249-2259, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38165279

RESUMEN

Lithium-sulfur batteries (LSBs) are one of the most promising energy storage devices with high energy density. However, their application and commercialization are hampered by the slow Li-S redox chemistry. Fe0.875M0.125S2 (M = Ti, V), as the sulfur cathode host, enhances the Li-S redox chemistry. FeS2 with Pa3̄ is transformed into Li2FeS2 with P3̄m1 after discharge. The structure changes and physicochemical properties during Fe0.875M0.125S2 discharge process are further investigated to screen out the sulfur cathode host materials with the best comprehensive properties. The discharge structure of Fe0.875M0.125S2 is verified by the thermodynamic stability of Li-deficient phases, voltage and capacity based on Monte Carlo methods. Fe0.875M0.125S2 with Pa3̄ is transformed into Li2Fe0.875M0.125S2 with P3̄m1 after discharge. Using the first-principles calculations, the physicochemical properties of Li2Fe0.875M0.125S2 are systematically investigated, including the formation energy, voltage, theoretical capacity, electrical conductivity, Li+ diffusion, catalytic performance and Li2S oxidation decomposition. The average redox voltage of Li2Fe0.875V0.125S2 is higher than that of Li2Fe0.875Ti0.125S2. Li2Fe0.875M0.125S2 shows metallic properties. Li2Fe0.875V0.125S2 is more beneficial to the reduction reaction of Li2S2 and Li2S oxidation decomposition. Fe0.875V0.125S2 has more potential as the sulfur cathode host than Fe0.875Ti0.125S2 in LSBs. A new strategy for the selection of the sulfur cathode host material for LSBs is provided by this work.

18.
Antioxid Redox Signal ; 40(1-3): 145-167, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37548538

RESUMEN

Significance: Gasotransmitters, including nitric oxide (NO), hydrogen sulfide (H2S) and sulfur dioxide (SO2), participate in various cellular processes via corresponding oxidative posttranslational modifications (oxiPTMs) of specific cysteines. Recent Advances: Accumulating evidence has clarified the mechanisms underlying the formation of oxiPTMs derived from gasotransmitters and their biological functions in multiple signal pathways. Because of the specific existence and functional importance, determining the sites of oxiPTMs in cysteine is crucial in biology. Recent advances in the development of selective probes, together with upgraded mass spectrometry (MS)-based proteomics, have enabled the quantitative analysis of cysteinome. To date, several cysteine residues have been identified as gasotransmitter targets. Critical Issues: To clearly understand the underlying mechanisms for gasotransmitter-mediated biological processes, it is important to identify modified targets. In this review, we summarize the chemical formation and biological effects of gasotransmitter-dependent oxiPTMs and highlight the state-of-the-art detection methods. Future Directions: Future studies in this field should aim to develop the next generation of probes for in situ labeling to improve spatial resolution and determine the dynamic change of oxiPTMs, which can lay the foundation for research on the molecular mechanisms and clinical translation of gasotransmitters. Antioxid. Redox Signal. 40, 145-167.


Asunto(s)
Gasotransmisores , Sulfuro de Hidrógeno , Gasotransmisores/metabolismo , Cisteína/metabolismo , Sulfuro de Hidrógeno/metabolismo , Óxido Nítrico/metabolismo , Oxidación-Reducción , Procesamiento Proteico-Postraduccional , Estrés Oxidativo
19.
Phytomedicine ; 123: 155227, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38128398

RESUMEN

BACKGROUND: Atherosclerosis (AS) is a progressive chronic disease. Currently, cardiovascular diseases (CVDs) caused by AS is responsible for the global increased mortality. Yanshanjiang as miao herb in Guizhou of China is the dried and ripe fruit of Fructus Alpinia zerumbet. Accumulated evidences have confirmed that Yanshanjiang could ameliorate CVDs, including AS. Nevertheless, its effect and mechanism on AS are still largely unknown. PURPOSE: To investigate the role of essential oil from Fructus Alpinia zerumbet (EOFAZ) on AS, and the potential mechanism. METHODS: A high-fat diet (HFD) ApoE-/- mice model of AS and a oxLDL-induced model of macrophage-derived foam cells (MFCs) were reproduced to investigate the pharmacological properties of EOFAZ on AS in vivo and foam cell formation in vitro, respectively. The underlying mechanisms of EOFAZ were investigated using Network pharmacology and molecular docking. EOFAZ effect on PPARγ protein stability was measured using a cellular thermal shift assay (CETSA). Pharmacological agonists and inhibitors and gene interventions were employed for clarifying EOFAZ's potential mechanism. RESULTS: EOFAZ attenuated AS progression in HFD ApoE-/- mice. This attenuation was manifested by the reduced aortic intima plaque development, increased collagen content in aortic plaques, notable improvement in lipid profiles, and decreased levels of inflammatory factors. Moreover, EOFAZ inhibited the formation of MFCs by enhancing cholesterol efflux through activiting the PPARγ-LXRα-ABCA1/G1 pathway. Interestingly, the pharmacological knockdown of PPARγ impaired the beneficial effects of EOFAZ on MFCs. Additionally, our results indicated that EOFAZ reduced the ubiquitination degradation of PPARγ, and the chemical composition of EOFAZ directly bound to the PPARγ protein, thereby increasing its stability. Finally, PPARγ knockdown mitigated the protective effects of EOFAZ on AS in HFD ApoE-/- mice. CONCLUSION: These findings represent the first confirmation of EOFAZ's in vivo anti-atherosclerotic effects in ApoE-/- mice. Mechanistically, its chemical constituents can directly bind to PPARγ protein, enhancing its stability, while reducing PPARγ ubiquitination degradation, thereby inhibiting foam cell formation via activation of the PPARγ-LXRα-ABCA1/G1 pathway. Simultaneously, EOFAZ could ameliorates blood lipid metabolism and inflammatory microenvironment, thus synergistically exerting its anti-atherosclerotic effects.


Asunto(s)
Alpinia , Aterosclerosis , Aceites Volátiles , Placa Aterosclerótica , Animales , Ratones , PPAR gamma/metabolismo , Aceites Volátiles/farmacología , Frutas , Simulación del Acoplamiento Molecular , Transducción de Señal , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/metabolismo , Placa Aterosclerótica/tratamiento farmacológico , Apolipoproteínas E , Transportador 1 de Casete de Unión a ATP/metabolismo , Receptores X del Hígado/metabolismo
20.
Cell Metab ; 36(1): 78-89.e5, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38113886

RESUMEN

Over 50 billion cells undergo apoptosis each day in an adult human to maintain immune homeostasis. Hydrogen sulfide (H2S) is also required to safeguard the function of immune response. However, it is unknown whether apoptosis regulates H2S production. Here, we show that apoptosis-deficient MRL/lpr (B6.MRL-Faslpr/J) and Bim-/- (B6.129S1-Bcl2l11tm1.1Ast/J) mice exhibit significantly reduced H2S levels along with aberrant differentiation of Th17 cells, which can be rescued by the additional H2S. Moreover, apoptotic cells and vesicles (apoVs) express key H2S-generating enzymes and generate a significant amount of H2S, indicating that apoptotic metabolism is an important source of H2S. Mechanistically, H2S sulfhydrates selenoprotein F (Sep15) to promote signal transducer and activator of transcription 1 (STAT1) phosphorylation and suppress STAT3 phosphorylation, leading to the inhibition of Th17 cell differentiation. Taken together, this study reveals a previously unknown role of apoptosis in maintaining H2S homeostasis and the unique role of H2S in regulating Th17 cell differentiation via sulfhydration of Sep15C38.


Asunto(s)
Sulfuro de Hidrógeno , Adulto , Ratones , Humanos , Animales , Sulfuro de Hidrógeno/farmacología , Sulfuro de Hidrógeno/metabolismo , Células Th17 , Ratones Endogámicos MRL lpr , Diferenciación Celular , Apoptosis
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