Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 71
Filtrar
1.
J Am Chem Soc ; 146(12): 8280-8297, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38467029

RESUMO

Single-site copper-based catalysts have shown remarkable activity and selectivity for a variety of reactions. However, deactivation by sintering in high-temperature reducing environments remains a challenge and often limits their use due to irreversible structural changes to the catalyst. Here, we report zeolite-based copper catalysts in which copper oxide agglomerates formed after reaction can be repeatedly redispersed back to single sites using an oxidative treatment in air at 550 °C. Under different environments, single-site copper in Cu-Zn-Y/deAlBeta undergoes dynamic changes in structure and oxidation state that can be tuned to promote the formation of key active sites while minimizing deactivation through Cu sintering. For example, single-site Cu2+ reduces to Cu1+ after catalyst pretreatment (270 °C, 101 kPa H2) and further to Cu0 nanoparticles under reaction conditions (270-350 °C, 7 kPa EtOH, 94 kPa H2) or accelerated aging (400-450 °C, 101 kPa H2). After regeneration at 550 °C in air, agglomerated CuO was dispersed back to single sites in the presence and absence of Zn and Y, which was verified by imaging, in situ spectroscopy, and catalytic rate measurements. Ab initio molecular dynamics simulations show that solvation of CuO monomers by water facilitates their transport through the zeolite pore, and condensation of the CuO monomer with a fully protonated silanol nest entraps copper and reforms the single-site structure. The capability of silanol nests to trap and stabilize copper single sites under oxidizing conditions could extend the use of single-site copper catalysts to a wider variety of reactions and allows for a simple regeneration strategy for copper single-site catalysts.

2.
Small ; : e2311500, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38372501

RESUMO

Singlet oxygen (term symbol 1 Δg , hereafter 1 O2 ), a reactive oxygen species, has recently attracted increasing interest in the field of rechargeable batteries and electrocatalysis and photocatalysis. These sustainable energy conversion and storage technologies are of vital significance to replace fossil fuels and promote carbon neutrality and finally tackle the energy crisis and climate change. Herein, the recent progresses of 1 O2 for energy storage and conversion is summarized, including physical and chemical properties, formation mechanisms, detection technologies, side reactions in rechargeable batteries and corresponding inhibition strategies, and applications in electrocatalysis and photocatalysis. The formation mechanisms and inhibition strategies of 1 O2 in particular aprotic lithium-oxygen (Li-O2 ) batteries are highlighted, and the applications of 1 O2 in photocatalysis and electrocatalysis is also emphasized. Moreover, the confronting challenges and promising directions of 1 O2 in energy conversion and storage systems are discussed.

3.
Lipids Health Dis ; 23(1): 97, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566047

RESUMO

BACKGROUND: Observational studies have suggested an association between birth weight and type 2 diabetes mellitus, but the causality between them has not been established. We aimed to obtain the causal relationship between birth weight with T2DM and quantify the mediating effects of potential modifiable risk factors. METHODS: Two-step, two-sample Mendelian randomization (MR) techniques were applied using SNPs as genetic instruments for exposure and mediators. Summary data from genome-wide association studies (GWAS) for birth weight, T2DM, and a series of fatty acids traits and their ratios were leveraged. The inverse variance weighted (IVW) method was the main analysis approach. In addition, the heterogeneity test, horizontal pleiotropy test, Mendelian randomization pleiotropy residual sum and outlier (MR-PRESSO) test, and leave-one-out analysis were carried out to assess the robustness. RESULTS: The IVW method showed that lower birth weight raised the risk of T2DM (ß: -1.113, 95% CI: -1.573 ∼ -0.652). Two-step MR identified 4 of 17 candidate mediators partially mediating the effect of lower birth weight on T2DM, including ratio of polyunsaturated fatty acids to monounsaturated fatty acids (proportion mediated: 7.9%), ratio of polyunsaturated fatty acids to total fatty acids (7.2%), ratio of omega-6 fatty acids to total fatty acids (8.1%) and ratio of linoleic acid to total fatty acids ratio (6.0%). CONCLUSIONS: Our findings supported a potentially causal effect of birth weight against T2DM with considerable mediation by modifiable risk factors. Interventions that target these factors have the potential to reduce the burden of T2DM attributable to low birth weight.


Assuntos
Diabetes Mellitus Tipo 2 , Ácidos Graxos , Humanos , Diabetes Mellitus Tipo 2/genética , Peso ao Nascer/genética , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Ácidos Graxos Monoinsaturados
4.
BMC Genomics ; 24(1): 648, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37891463

RESUMO

BACKGROUND: The Begonia species are common shade plants that are mostly found in southwest China. They have not been well studied despite their medicinal and decorative uses because gene penetration, decreased adaptability, and restricted availability are all caused by frequent interspecific hybridization. RESULT: To understand the patterns of mutation in the chloroplast genomes of different species of Begonia, as well as their evolutionary relationships, we collected seven Begonia species in China and sequenced their chloroplast genomes. Begonia species exhibit a quadripartite structure of chloroplast genomes (157,634 - 169,694 bp), consisting of two pairs of inverted repeats (IR: 26,529 - 37,674 bp), a large single copy (LSC: 75,477 - 86,500 bp), and a small single copy (SSC: 17,861 - 18,367 bp). 128-143 genes (comprising 82-93 protein-coding genes, 8 ribosomal RNAs, and 36-43 transfer RNAs) are found in the chloroplast genomes. Based on comparative analyses, this taxon has a relatively similar genome structure. A total of six substantially divergent DNA regions (trnT-UGU-trnL-UAA, atpF-atpH, ycf4-cemA, psbC-trnS-UGA, rpl32-trnL-UAG, and ccsA-ndhD) are found in the seventeen chloroplast genomes. These regions are suitable for species identification and phylogeographic analysis. Phylogenetic analysis shows that Begonia species that were suited to comparable environments grouped in a small clade and that all Begonia species formed one big clade in the phylogenetic tree, supporting the genus' monophyly. In addition, positive selection sites were discovered in eight genes (rpoC1, rpoB, psbE, psbK, petA, rps12, rpl2, and rpl22), the majority of which are involved in protein production and photosynthesis. CONCLUSION: Using these genome resources, we can resolve deep-level phylogenetic relationships between Begonia species and their families, leading to a better understanding of evolutionary processes. In addition to enhancing species identification and phylogenetic resolution, these results demonstrate the utility of complete chloroplast genomes in phylogenetically and taxonomically challenging plant groupings.


Assuntos
Begoniaceae , Genoma de Cloroplastos , Humanos , Filogenia , Begoniaceae/genética , Genômica/métodos , Cloroplastos/genética , Sequência de Bases
5.
Proc Natl Acad Sci U S A ; 117(23): 12576-12583, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-31767762

RESUMO

Technoeconomic and life-cycle analyses are presented for catalytic conversion of ethanol to fungible hydrocarbon fuel blendstocks, informed by advances in catalyst and process development. Whereas prior work toward this end focused on 3-step processes featuring dehydration, oligomerization, and hydrogenation, the consolidated alcohol dehydration and oligomerization (CADO) approach described here results in 1-step conversion of wet ethanol vapor (40 wt% in water) to hydrocarbons and water over a metal-modified zeolite catalyst. A development project increased liquid hydrocarbon yields from 36% of theoretical to >80%, reduced catalyst cost by an order of magnitude, scaled up the process by 300-fold, and reduced projected costs of ethanol conversion 12-fold. Current CADO products conform most closely to gasoline blendstocks, but can be blended with jet fuel at low levels today, and could potentially be blended at higher levels in the future. Operating plus annualized capital costs for conversion of wet ethanol to fungible blendstocks are estimated at $2.00/GJ for CADO today and $1.44/GJ in the future, similar to the unit energy cost of producing anhydrous ethanol from wet ethanol ($1.46/GJ). Including the cost of ethanol from either corn or future cellulosic biomass but not production incentives, projected minimum selling prices for fungible blendstocks produced via CADO are competitive with conventional jet fuel when oil is $100 per barrel but not at $60 per barrel. However, with existing production incentives, the projected minimum blendstock selling price is competitive with oil at $60 per barrel. Life-cycle greenhouse gas emission reductions for CADO-derived hydrocarbon blendstocks closely follow those for the ethanol feedstock.

6.
Small ; 18(43): e2107013, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35253367

RESUMO

MgH2 is one of the most promising solid hydrogen storage materials due to its high capacity, excellent reversibility, and low cost. However, its operation temperature needs to be greatly reduced to realize its practical applications, especially in the highly desired fuel cell fields. This work synthesizes a 2D nanoflake-shape bimetallic Ti-Nb oxide of TiNb2 O7 , which has high surface area and shows superior catalytic effect for the hydrogen storage of MgH2 . Incorporated with the TiNb2 O7 nanoflakes as low as 3 wt%, MgH2 shows a low onset dehydrogenation temperature of 178 °C, which is lowered by 100 °C compared with the pristine one. A dehydrogenation capacity as high as 7.0 wt% H2 is achieved upon heating to 300 °C. The capacity retention is as high as 96% after 30 cycles. The mechanism of the improved hydrogen storage properties is analyzed by density functional theory (DFT) calculation and the microstructural evolution during dehydrogenation and hydrogenation. This work provides an MgH2 system with high available capacity and low operation temperature by a unique structural design of the catalyst. The high surface area feature of the TiNb2 O7 nanoflakes and the synthesis method hopefully can develop the application of TiNb2 O7 .

7.
Hepatology ; 73(4): 1419-1435, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32750152

RESUMO

BACKGROUND AND AIMS: Circular RNAs (circRNAs) and extracellular vesicles (EVs) are involved in various malignancies. We aimed to clarify the functions and mechanisms of dysregulated circRNAs in the cells and EVs of cholangiocarcinoma (CCA). APPROACH AND RESULTS: CircRNA microarray was used to identify circRNA expression profiles in CCA tissues and bile-derived EVs (BEVs). CCA-associated circRNA 1 (circ-CCAC1) expression was measured by quantitative real-time PCR. The clinical importance of circ-CCAC1 was analyzed by receiver operating characteristic curves, Fisher's exact test, Kaplan-Meier plots, and Cox regression model. The functions of circ-CCAC1 and exosomal circ-CCAC1 were explored in CCA cells and human umbilical vein endothelial cells (HUVECs), respectively. Different animal models were used to verify the in vitro results. RNA sequencing, bioinformatics, RNA immunoprecipitation, RNA pulldown, chromatin immunoprecipitation followed by sequencing, and luciferase reporter assays were used to determine the regulatory networks of circ-CCAC1 in CCA cells and HUVECs. Circ-CCAC1 levels were increased in cancerous bile-resident EVs and tissues. The diagnostic and prognostic values of circ-CCAC1 were identified in patients with CCA. For CCA cells, circ-CCAC1 increased cell progression by sponging miR-514a-5p to up-regulate Yin Yang 1 (YY1). Meanwhile, YY1 directly bound to the promoter of calcium modulating ligand to activate its transcription. Moreover, circ-CCAC1 from CCA-derived EVs was transferred to endothelial monolayer cells, disrupting endothelial barrier integrity and inducing angiogenesis. Mechanistically, circ-CCAC1 increased cell leakiness by sequestering enhancer of zeste homolog 2 in the cytoplasm, thus elevating SH3 domain-containing GRB2-like protein 2 expression to reduce the levels of intercellular junction proteins. In vivo studies further showed that increased circ-CCAC1 levels in circulating EVs and cells accelerated both CCA tumorigenesis and metastasis. CONCLUSIONS: Circ-CCAC1 plays a vital role in CCA tumorigenesis and metastasis and may be an important biomarker/therapeutic target for CCA.


Assuntos
Neoplasias dos Ductos Biliares/sangue , Carcinogênese/metabolismo , Colangiocarcinoma/sangue , Endotélio Vascular/metabolismo , Neovascularização Patológica/metabolismo , RNA Circular/sangue , RNA Circular/genética , Animais , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/patologia , Carcinogênese/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Sobrevivência Celular/genética , Colangiocarcinoma/genética , Colangiocarcinoma/patologia , Coledocolitíase/sangue , Coledocolitíase/genética , Coledocolitíase/patologia , Vesículas Extracelulares/metabolismo , Técnicas de Silenciamento de Genes , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos , Camundongos Nus , Reação em Cadeia da Polimerase em Tempo Real , Transfecção , Carga Tumoral/genética , Ensaios Antitumorais Modelo de Xenoenxerto
8.
World J Surg Oncol ; 19(1): 229, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34348716

RESUMO

BACKGROUND: Digestive tract reconstruction in totally laparoscopic total gastrectomy can be divided into two types: instrument anastomosis and hand-sewn anastomosis. This study explored the feasibility and safety of hand-sewn sutures in esophagojejunostomy of totally laparoscopic total gastrectomy, compared with instrument anastomosis using an overlap linear cutter. METHODS: This retrospective cohort study was conducted from January 2017 to January 2020 at one institution. The clinical data of 50 patients who underwent totally laparoscopic total gastrectomy, with an average follow-up time of 12 months, were collected. The clinicopathologic data, short-term survival prognosis, and results of patients in the hand-sewn anastomosis (n=20) and the overlap anastomosis (n=30) groups were analyzed. RESULTS: There were no significant differences between the groups in sex, age, body mass index, American Society of Anesthesiologists score, tumor location, preoperative complications, abdominal operation history, tumor size, pTNM stage, blood loss, first postoperative liquid diet, exhaust time, or postoperative length of hospital stay. The hand-sewn anastomosis group had a significantly prolonged operation time (204±26.72min versus 190±20.90min, p=0.04) and anastomosis time (58±22.0min versus 46±15.97min, p=0.029), and a decreased operation cost (CNY 77,100±1700 versus CNY 71,900±1300, p<0.0001). Postoperative complications (dynamic ileus, abdominal infection, and pancreatic leakage) occurred in three patients (15%) in the hand-sewn anastomosis group and in four patients (13.3%) in the overlap anastomosis group (anastomotic leakage, anastomotic bleeding, dynamic ileus, and duodenal stump leakage). CONCLUSION: The hand-sewn anastomosis method of esophagojejunostomy under totally laparoscopic total gastrectomy is safe and feasible and is an important supplement to linear and circular stapler anastomosis. It may be more convenient regarding obesity, a relatively high position of the anastomosis, edema of the esophageal wall, and short jejunal mesentery.


Assuntos
Laparoscopia , Neoplasias Gástricas , Anastomose Cirúrgica/efeitos adversos , Gastrectomia/efeitos adversos , Humanos , Complicações Pós-Operatórias/etiologia , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/cirurgia , Técnicas de Sutura
9.
Cancer Cell Int ; 20: 324, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32694946

RESUMO

BACKGROUND: Cholangiocarcinoma (CCA) is a mortal cancer with high mortality, whereas the function and mechanism of occurrence and progression of CCA are still mysterious. Long non-coding RNAs (lncRNAs) could function as important regulators in carcinogenesis and cancer progression. Growing evidences have indicated that the novel lncRNA linc00473 plays an important role in cancer progression and metastasis. However, its function and molecular mechanism in CCA remain unknown. METHODS: The linc00473 expression in CCA tissues and cell lines was analyzed using qRT-PCR. Gain- and loss-of-function experiments were conducted to investigate the biological functions of linc00473 both in vitro and in vivo. Insights into the underlying mechanisms of competitive endogenous RNAs (ceRNAs) were determined by bioinformatics analysis, dual-luciferase reporter assays, qRT-PCR arrays, RNA immunoprecipitation (RIP) and rescue experiments. RESULTS: Linc00473 was highly expressed in CCA tissues and cell lines. Linc00473 knockdown inhibited CCA growth and metastasis. Furthermore, linc00473 acted as miR-506 sponge and regulated its target gene DDX5 expression. Rescue assays verified that linc00473 modulated the tumorigenesis of CCA by regulating miR-506. CONCLUSIONS: The data indicated that linc00473 played an oncogenic role in CCA growth and metastasis, and could serve as a novel molecular target for treating CCA.

10.
J Cell Mol Med ; 23(12): 8258-8268, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31565837

RESUMO

LncRNAs has been demonstrated to modulate neoplastic development by modulating downstream miRNAs and functional genes. In this study, we aimed to detect the interaction among lncRNA ZFAS1 miR-296-5p and USF1. We explored the proliferation, migration and invasion of cholangiocarcinoma. The differentially expressed ZFAS1 was discovered in both tissues and cell lines by qRT-PCR. The targeting relationship between miR-296-5p and ZFAS1 or USF1 was validated by dual-luciferase assay. The impact of ZFAS1 on CCA cell proliferation was observed by CCK-8 assay. The protein expression of USF1 was determined by Western blot. The effects of ZFAS1, miR-296-5p and USF1 on tumour growth were further confirmed using xenograft model. LncRNA ZFAS1 expression was relatively up-regulated in tumour tissues and cells while miR-296-5p was significantly down-regulated. Knockdown of ZFAS1 significantly suppressed tumour proliferation, migration, invasion and USF1 expression. Overexpressed miR-296-5p suppressed cell proliferation and metastasis. Knockdown of USF1 inhibited cell proliferation and metastasis and xenograft tumour growth. In conclusion, ZFAS1 might promote cholangiocarcinoma proliferation and metastasis by modulating USF1 via miR-296-5p.


Assuntos
Neoplasias dos Ductos Biliares/genética , Proliferação de Células/genética , Colangiocarcinoma/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Fatores Estimuladores Upstream/genética , Animais , Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/terapia , Linhagem Celular Tumoral , Colangiocarcinoma/metabolismo , Colangiocarcinoma/terapia , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , Interferência de RNA , Terapêutica com RNAi/métodos , Análise de Sobrevida , Regulação para Cima , Fatores Estimuladores Upstream/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
11.
J Cell Physiol ; 234(10): 17113-17126, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30888066

RESUMO

Cholangiocarcinoma (CCA) is one of the most fatal cancers in humans, with a gradually increasing incidence worldwide. The efficient diagnostic and therapeutic measures for CCA to reduce mortality are urgently needed. Long noncoding RNAs (lncRNAs) may provide the potential diagnostic and therapeutic option for suppressing the CCA development. LncRNAs are a type of non-protein-coding RNAs, which are larger than 200 nucleotides in length. Increasing evidence reveals that lncRNAs exhibit critical roles in the carcinogenesis and development of CCA. Deregulation of lncRNAs impacts the proliferation, migration, invasion, and antiapoptosis of CCA cells by multiple sophisticated mechanisms. Consequently, lncRNAs likely represent promising biomarkers or intervention targets of CCA. In this review, we summarize current studies regarding the biological functions and regulatory mechanisms of diverse lncRNAs in CCA.


Assuntos
Neoplasias dos Ductos Biliares/genética , Colangiocarcinoma/genética , RNA Longo não Codificante/genética , Animais , Carcinogênese/genética , Humanos
12.
J Biomed Sci ; 25(1): 23, 2018 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-29534728

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNAs), which are a portion of non-protein-coding RNAs (ncRNAs), have manifested a paramount role in the pathophysiology of human diseases, particularly in pathogenesis and progression of disease. Myocardial infarction associated transcript (MIAT), which was recently found to demonstrate aberrant expression in various diseases, such as myocardial infarction, schizophrenia, ischemic stroke, diabetic complications, age-related cataract and cancers, is a novel disease-related lncRNA. This work summarize current evidence regarding the biological functions and underlying mechanisms of lncRNA MIAT during disease development. SHORT CONCLUSION: LncRNA MIAT likely represents a feasible cancer biomarker or therapeutic target.


Assuntos
Biomarcadores Tumorais/genética , Infarto do Miocárdio/genética , Doenças não Transmissíveis , RNA Longo não Codificante/genética , Biomarcadores/metabolismo , Biomarcadores Tumorais/metabolismo , Humanos , RNA Longo não Codificante/metabolismo
14.
Phys Chem Chem Phys ; 19(21): 13679-13686, 2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28497134

RESUMO

In this work, the influence of oxygen vacancy defect (OVD) in compact titanium oxide (c-TiO2) on the performance of planar perovskite solar cells (p-PSCs) is investigated, and the possible mechanisms are also proposed. To meet our objective, anatase c-TiO2 thin films with various OVD concentrations are prepared by changing the oxygen flux during the DC magnetron sputtering process and are characterized by the intensity of defect signals in the X-ray photoelectron spectra. We conclude that abundant OVDs can trigger an obviously increased majority carrier accumulation zone at the metal oxide/perovskite interface and enhanced capacitance, thereby greatly deteriorating photogenerated carrier collection efficiency. A detailed analysis of the study results also reveals that the presence of OVD in the bulk and surface of c-TiO2 can slow down electronic carrier transport and lower its electron quasi-Fermi level under illumination, leading to the detrimental charge recombination in p-PSCs. Furthermore, we report a remarkably enhanced p-PSC efficiency via preparing c-TiO2 using high oxygen flux and subsequent ultraviolet ozone treatment. As a consequence, repeatable power conversion efficiency (PCE) is propelled to as high as 16.62%, coupled with negligible hysteresis and increased stability. These results provide a significant implication for further perfecting efficient and stable p-PSCs for their record efficiency.

15.
Sci Total Environ ; 924: 171547, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38458467

RESUMO

Pretreatment process is considered as the most important step for effective microalgae biomass refining and has gained more interest since last decades. However, the main obstacles to commercialize microalgae products are recalcitrant cell wall and lack of cost-effective, green, and sustainable pretreatment approaches. Till now, various microalgae pretreatment approaches have been applied prior to extraction steps to enhance the accessibility of solvent inside the cells. However, high energy consumption and the hazardousness of solvents are considerable problem for these pretreatment methods. In this regard, deep eutectic solvents are recognized as sustainable and green solvents possessing great potential for microalgae biomass processing due to their low toxicity, low cost, biodegradability, easy recycling, and reuse. This article provides the fundamentals of DES composition, synthesis, properties, and the current advances in the application of microalgae biomass process.


Assuntos
Lignina , Microalgas , Solventes Eutéticos Profundos , Biomassa , Solventes
16.
Phytomedicine ; 128: 155341, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38518636

RESUMO

BACKGROUND: Atherosclerosis (AS) is a chronic disease characterized by lipid accumulation in the aortic wall and the formation of foam cells overloaded with large lipids inclusions. Currently, Western medicine is primarily used to improve lipid metabolism disorders and reduce inflammatory reactions to delay AS progression, but these medicines come with serious side effects and drug resistance. Gualou-Xiebai (GLXB) is a renowned herb pair that has been proven effective against AS. However, the potential molecular mechanism through which GLXB exerts the anti-atherosclerotic effects of increasing lipophagy in vascular smooth muscle cells (VSMCs) remains unknown. PURPOSE: This study aims to explore the role of lipophagy and the therapeutic mechanism of GLXB in AS. METHODS: UPLC-Q-TOF-MS for the determination of the main components of GLXB-containing serum. An AS mouse model was established by feeding a high-fat diet (HFD) to ApoE-/- mice for 12 weeks. Ultrasonography monitoring was used to confirm the successful establishment of the AS model. Plaque areas and lipid deposition were evaluated using HE staining and aorta imagingafter GLXB treatment. Immunofluorescence staining and Western blotting were utilized to observe the P2RY12 and lipophagy levels in AS mice. VSMCs were stimulated with oxidized low-density lipoprotein (ox-LDL) to induce foam cell formation. The degree of lipophagy and the related molecular mechanisms were assessed after treating the VSMCs with GLXB-containing serum or si-P2RY12 transfection. The active components of GLXB-containing serum that act on P2RY12 were screened and verified by molecular docking and dual-luciferase reporter assays. RESULTS: Seventeen components of GLXB were identified in rat serum by UPLC-Q-TOF-MS. GLXB significantly reduced lipid deposition in HFD-fed ApoE-/- mice and ox-LDL-induced VSMCs. GLXB strikingly increased lipophagy levels by downregulating P2RY12, p62, and plin2, upregulating LC3Ⅱ protein expression, and increasing the number of autophagosomes. Notably, the lipophagy inhibitor CQ and the P2RY12 receptor agonist ADPß abolished the GLXB-induced increase in lipophagy. Last, we confirmed that albiflorin, apigenin, luteolin, kaempferol, 7,8-dihydroxyflavone, and hesperetin from GLXB significantly inhibited P2RY12. CONCLUSION: GLXB activates lipophagy and inhibits lipid accumulation-associated VSMC-derived foam cell formation through suppressing P2RY12 activation, resulting in anti-atherosclerotic effects. The GLXB components albiflorin, apigenin, luteolin, kaempferol, 7,8-dihydroxyflavone, and hesperetin are the potential active effectors against P2RY12.


Assuntos
Aterosclerose , Medicamentos de Ervas Chinesas , Células Espumosas , Músculo Liso Vascular , Receptores Purinérgicos P2Y12 , Animais , Aterosclerose/tratamento farmacológico , Células Espumosas/efeitos dos fármacos , Células Espumosas/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Masculino , Camundongos , Medicamentos de Ervas Chinesas/farmacologia , Receptores Purinérgicos P2Y12/metabolismo , Dieta Hiperlipídica , Camundongos Endogâmicos C57BL , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Ratos , Modelos Animais de Doenças , Autofagia/efeitos dos fármacos , Ratos Sprague-Dawley , Metabolismo dos Lipídeos/efeitos dos fármacos , Aorta/efeitos dos fármacos , Lipoproteínas LDL/metabolismo
17.
Curr Neurovasc Res ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38629368

RESUMO

BACKGROUND: Gualou is derived from the fruit of Trichosanthes kirilowii Maxim, while Xiebai from the bulbs of Allium macrostemon Bunge. Gualou and Xiebai herb pair (2:1) is widely used in clinical practice to treat atherosclerotic cardiovascular diseases. However, the mechanism underlying its potential activity on atherosclerosis (AS) has not been fully elucidated. METHODS: The extract of Gualou-Xiebai herb pair (GXE) was prepared from Gualou (80 g) and Xiebai (40 g) by continuous refluxing with 50% ethanol for 2 h at 80°C. In vivo, ApoE-/- mice were fed a high-fat diet (HFD) for 10 weeks to induce an AS model, and then the mice were treated with GXE (3, 6, 12 g/kg) or atorvastatin (10 mg/kg) via oral gavage. Besides, RAW264.7 macrophages were stimulated by ox-LDL to establish a foam cell model in vitro. RESULTS: GXE suppressed plaque formation, regulated plasma lipids, and promoted liver lipid clearance in AS mice. In addition, 0.5, 1, and 2 mg/mL GXE significantly reduced the TC and FC levels in ox-LDL (50 µg/mL)-stimulated foam cells. GXE increased cholesterol efflux from the foam cells to ApoA-1 and HDL, and enhanced the protein expressions of ABCA1, ABCG1, and SR-BI, which were reversed by the PPARγ inhibitor. Meanwhile, GXE increased the LCAT levels, decreased the lipid levels and increased the TBA levels in the liver of AS mice. Molecular docking indicated that some compounds in GXE showed favorable binding energy with PPARγ, LCAT and CYP7A1 proteins, especially apigenin-7-O-ß-D-glucoside and quercetin. CONCLUSION: In summary, our results suggested that GXE improved lipid metabolism disorders by enhancing RCT, providing a scientific basis for the clinical use of GXE in AS treatment.

18.
J Ethnopharmacol ; 326: 117892, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38350505

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Atherosclerosis (AS) is a chronic vascular ailment characterized by inflammatory and lipid deposition in the arterial wall caused by endothelial injury. Ferroptosis is a novel type of cell death, and endothelial ferroptosis is a significant contributor to the progression of AS. Gualou-Xiebai (GLXB) is a renowned Chinese herb pair that serves a crucial function in treating AS. However, whether the underlying mechanism of GLXB plays a role in anti-atherosclerotic effects by inhibiting ferroptosis in endothelial cells has not been determined. AIM OF THE STUDY: To explore the influence of GLXB on endothelial ferroptosis and determine its underlying mechanism of action in AS. MATERIALS AND METHODS: In ApoE-/- mice, ultrasound was performed in mice fed a high-fat diet (HFD) for 12 weeks to assess the success of AS establishment. Then, ApoE-/- mice were treated with GLXB and Simvastatin (positive control) for 4 weeks. The effects of GLXB on AS pathology were assessed through aorta imaging and hematoxylin-eosin (HE) staining. To confirm the presence of ferroptosis, mitochondrial damage was observed using transmission electron microscope (TEM), along with analysis of free iron and lipid peroxidation levels. In vitro: ox-LDL-induced human vascular endothelial cells (HUVECs) injury and treated with GLXB, the ferroptosis inducer Erastin and an Nrf2 inhibitor ML385. Cell viability was evaluated using the CCK-8 assay in all groups. Flow cytometry was employed to detect lipid peroxidation and intracellular ferrous iron levels. Immunofluorescence staining microscopy verified Nrf2 nuclear translocation. Protein expression were measured by Western blot analysis. RESULTS: GLXB improved atherosclerotic aortic lesions and vascular plaques. GLXB inhibited endothelial injury in the aorta by decreasing the levels of inflammatory factors and adhesion factors, and by decreasing the shedding of endothelial cells. GLXB suppressed ferroptosis in ApoE-/- mice by attenuating mitochondrial damage in ECs, increasing the levels of glutathione (GSH) and superoxide dismutase (SOD) in aortic tissues and down-regulating the levels of levels of lipid peroxide (LPO) and malondialdehyde (MDA). Interestingly, Erastin was used to demonstrate in vitro that GLXB inhibition of ferroptosis attenuated ox-LDL-induced injuring effects on HUVECs that were reversed by Erastin. Mechanistically, GLXB activates the Nrf2 signaling pathway to inhibit ferroptosis by increasing downstream anti-ferroptosis target proteins and promoting the interaction between Nrf2 and SLC7A11. More convincingly, ML385 (Nrf2 inhibitor) reversed the anti-ferroptosis effect of GLXB. CONCLUSION: GLXB inhibits ferroptosis-mediated endothelial cell injury via activating the Nrf2 signaling pathway and further alleviates AS pathological damage.


Assuntos
Aterosclerose , Ferroptose , Lipoproteínas LDL , Humanos , Animais , Camundongos , Células Endoteliais , Fator 2 Relacionado a NF-E2/metabolismo , Dieta Hiperlipídica/efeitos adversos , Aterosclerose/metabolismo , Apolipoproteínas E/genética , Ferro/metabolismo
19.
Nat Commun ; 15(1): 928, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38296957

RESUMO

Non-dissociative chemisorption solid-state storage of hydrogen molecules in host materials is promising to achieve both high hydrogen capacity and uptake rate, but there is the lack of non-dissociative hydrogen storage theories that can guide the rational design of the materials. Herein, we establish generalized design principle to design such materials via the first-principles calculations, theoretical analysis and focused experimental verifications of a series of heteroatom-doped-graphene-supported Ca single-atom carbon nanomaterials as efficient non-dissociative solid-state hydrogen storage materials. An intrinsic descriptor has been proposed to correlate the inherent properties of dopants with the hydrogen storage capability of the carbon-based host materials. The generalized design principle and the intrinsic descriptor have the predictive ability to screen out the best dual-doped-graphene-supported Ca single-atom hydrogen storage materials. The dual-doped materials have much higher hydrogen storage capability than the sole-doped ones, and exceed the current best carbon-based hydrogen storage materials.

20.
ACS Nano ; 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38334290

RESUMO

LiBH4 is one of the most promising candidates for use in all-solid-state lithium batteries. However, the main challenges of LiBH4 are the poor Li-ion conductivity at room temperature, excessive dendrite formation, and the narrow voltage window, which hamper practical application. Herein, we fabricate a flexible polymeric electronic shielding layer on the particle surfaces of LiBH4. The electronic conductivity of the primary LiBH4 is reduced by 2 orders of magnitude, to 1.15 × 10-9 S cm-1 at 25 °C, due to the high electron affinity of the electronic shielding layer; this localizes the electrons around the BH4- anions, which eliminates electronic leakage from the anionic framework and leads to a 68-fold higher critical electrical bias for dendrite growth on the particle surfaces. Contrary to the previously reported work, the shielding layer also ensures fast Li-ion conduction due to the fast-rotational dynamics of the BH4- species and the high Li-ion (carrier) concentration on the particle surfaces. In addition, the flexibility of the layer guarantees its structural integrity during Li plating and stripping. Therefore, our LiBH4-based solid-state electrolyte exhibits a high critical current density (11.43 mA cm-2) and long cycling stability of 5000 h (5.70 mA cm-2) at 25 °C. More importantly, the electrolyte had a wide operational temperature window (-30-150 °C). We believe that our findings provide a perspective with which to avoid dendrite formation in hydride solid-state electrolytes and provide high-performance all-solid-state lithium batteries.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa