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2.
Front Psychiatry ; 15: 1399167, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39328343

RESUMO

The hospital is a workplace full of stressful events for healthcare workers (HCWs) due to unpredictable changes in their daily routines. Perceptions of stressful events (stress mindset) have a significant impact on an individual's health and well-being. However, few studies have reported the factors and potential counter mechanisms influencing these perceptions. This study aimed to evaluate the relationship between empathy, self-disclosure, social support, and stress mindset of HCWs, and to explore the mechanism of empathy on stress mindset. Five hundred and eight HCWs (35.2% men and 64.8% women) completed the Interpersonal Reactivity Index (IRI), the Distress Disclosure Index (DDI), the Social Support Rating Scale (SSRS), the Stress Mindset Measure (SMM), and demographic questionnaires online in China. The results showed that empathy was positively linked with stress mindset and positively correlated with self-disclosure and social support. In the multiple mediating model, self-disclosure and social support mediated the association between empathy and stress mindset sequentially. The results imply that empathy, self-disclosure, and social support play a significant role in the formation of HCWs' stress mindset. These findings have substantial ramifications for reducing stress and creating successful government interventions to fortify stress mindset in healthcare.

3.
J Psychiatr Res ; 178: 259-269, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39167905

RESUMO

BACKGROUND: Each year, 3-4% of the global population experiences post-traumatic stress disorder (PTSD), a chronic mental disorder with significant social and economic repercussions. Although it has been shown that ketamine can effectively alleviate PTSD symptoms in individuals, the specific mechanism of action underlying its anti-PTSD effects remains unclear. In this study, we investigated how a single, low dose of ketamine affected the glycogen synthase kinase 3ß (GSK-3ß)/glucocorticoid receptor (GR) signaling pathway in a single prolonged stress (SPS)-induced PTSD rat model. METHODS: After establishing the model, stress-related behavioral alterations in the rats were assessed following intraperitoneal injections of ketamine (10 mg/kg) and GSK-3ß antagonist SB216763 (5 mg/kg). In the hippocampus, alterations in the expression of specific proteins implicated in PTSD development, such as GR, brain-derived neurotrophic factor (BDNF), GSK-3ß, and phosphorylated glycogen synthase kinase 3ß (p-GSK-3ß), were assessed. We also measured changes in the mRNA expression levels of GR, BDNF, GSK-3ß, FK501 binding protein 51 (FKBP5), and corticotropin-releasing hormone (CRH), as well as synaptic ultrastructure, in the hippocampus, and measured changes in corticosterone levels in the blood. RESULTS: SPS induced anxiety-like and depression-like behaviors in rats and induced morphological changes in synapse, which were accompanied by higher GSK-3ß protein expression and conversely, decreased expression of GR, BDNF, p-GSK-3ß, FKBP5 and CRH. Intraperitoneal administration of ketamine (10 mg/kg) after SPS prevented SPS-induced anxiety-like behaviors. Most importantly, ketamine attenuated SPS-induced dysfunctions in GSK-3ß/GR signaling and synaptic deficits. Furthermore, treatment with a GSK-3ß inhibitor played the same effect as ketamine on behavioral changes of SPS model rats. CONCLUSION: Single doses of ketamine effectively ameliorate SPS-induced anxiety-like symptoms, potentially by improving synaptic plastic in the hippocampus by regulating GSK-3ß/GR signaling.


Assuntos
Modelos Animais de Doenças , Glicogênio Sintase Quinase 3 beta , Hipocampo , Ketamina , Plasticidade Neuronal , Ratos Sprague-Dawley , Transdução de Sinais , Transtornos de Estresse Pós-Traumáticos , Animais , Ketamina/farmacologia , Ketamina/administração & dosagem , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Transtornos de Estresse Pós-Traumáticos/metabolismo , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Masculino , Plasticidade Neuronal/efeitos dos fármacos , Plasticidade Neuronal/fisiologia , Transdução de Sinais/efeitos dos fármacos , Ratos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/efeitos dos fármacos , Antagonistas de Aminoácidos Excitatórios/farmacologia , Antagonistas de Aminoácidos Excitatórios/administração & dosagem , Comportamento Animal/efeitos dos fármacos , Indóis , Maleimidas
4.
Angew Chem Int Ed Engl ; : e202412835, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39172117

RESUMO

Single-atom alloy (SAA) catalysts exhibit huge potential in heterogeneous catalysis. Manufacturing SAAs requires complex and expensive synthesis methods to precisely control the atomic scale dispersion to form diluted alloys with less active sites and easy sintering of host metal, which is still in the early stages of development.  Here, we address these limitations with a straightforward strategy from a brand-new perspective involving the 'islanding effect' for manufacturing SAAs without dilution: homogeneous RuNi alloys were continuously refined to highly dispersed alloy-islands (~ 1 nm) with completely single-atom sites where the relative metal loading was as high as 40%. Characterized by advanced atomic-resolution techniques, single Ru atoms were bonded with Ni as SAAs with extraordinary long-term stability and no sintering of the host metal. The SAAs exhibited 100% CO selectivity, over 55 times reverse water-gas shift (RWGS) rate than the alloys with Ru cluster sites, and over 3-4 times higher than SAAs by the dilution strategy. This study reports a one-step manufacturing strategy for SAA's using the wetness impregnation method with durable high atomic efficiency and holds promise for large-scale industrial applications.

5.
ChemSusChem ; : e202400128, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39045636

RESUMO

WOx/ZrO2 with a higher concentration of Brønsted acid sites (BAS) and a bigger ratio of Brønsted to Lewis acid sites (B/L) than achievable by conventional impregnation (IM) were synthesized using flame spray pyrolysis (FSP). The rapid quenching and short residence time inherent to FSP prevent the accumulation of W atoms on the ZrO2 support and thus provide an excellent surface dispersion of WOx species. As a result, FSP-made WOx/ZrO2 (FSP-WOx/ZrO2) has a much higher surface concentration of three-dimensional Zr-WOx clusters than corresponding materials prepared by conventional impregnation (IM-WOx/ZrO2). The coordination of W-OH to the unsaturated Zr4+ sites in these clusters results in a remarkable decrease of the concentration of Lewis acid sites (LAS) on the surface of ZrO2 and promotes the formation of bridging W-O(H)-Zr hydroxyl groups acting as BAS. FSP-WOx/ZrO2 possesses ~80% of BAS and a B/L ratio of around 4, while IM-WOx/ZrO2 exhibits ~50% BAS and a B/L ratio of around 1. These catalysts were evaluated in the dehydration of glucose to HMF. The catalytic study demonstrated that B/L ratio plays a crucial role in glucose conversion. The best catalyst, FSP-WOx/ZrO2 with a W/Zr ratio of 1/10 affords nearly 100% glucose conversion and an HMF selectivity of 56-69%.

6.
Anal Chem ; 96(26): 10851-10859, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38912707

RESUMO

Mitochondrial Membrane Chromatography (MMC) is a bioaffinity chromatography technique developed to study the interaction between target proteins embedded in the mitochondrial membrane and their ligand compounds. However, the MMC stationary phases (MMSP) prepared by chemical immobilization are prone to nonspecific binding in candidate agent screening inevitably. To address these challenges, Twin Strep-Tag/Strep Tactin was employed to establish a specific affinity system in the present study. We prepared a carnitine palmitoyltransferase 1A (CPT1A) MMSP by specifically linking Strep-tactin-modified silica gel with the Twin Strep-Tag on the CPT1A-oriented mitochondrial membrane. This Twin Strep-Tag/Strep Tactin modified CPT1A/MMC method exhibited remarkably better retention behavior, longer stationary phase lifespan, and higher screening specificity compared with previous MMC systems with glutaraldehyde immobilization. We adopted the CPT1A-specific MMC system in screening CPT1A ligands from traditional Chinese medicines, and successfully identified novel candidate ligands: ononin, isoliquiritigenin, and aloe-emodin, from Glycyrrhiza uralensis Fisch and Senna tora (L.) Roxb extracts. Biological assessments illustrated that the compounds screened promote CPT1A enzyme activity without affecting CPT1A protein expression, as well as effectively reduce the lipid droplets and triglyceride levels in the high fat induction HepG2 cells. The results suggest that we have developed an MMC system, which is promising for studying the bioaffinity of mitochondrial membrane proteins to candidate compounds. This system provides a platform for a key step in mitochondrial medicine discovery, especially for bioactive molecule screening from complex herbal extracts.


Assuntos
Carnitina O-Palmitoiltransferase , Metabolismo dos Lipídeos , Membranas Mitocondriais , Humanos , Carnitina O-Palmitoiltransferase/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Cromatografia de Afinidade , Ligantes
7.
Chempluschem ; : e202300511, 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38853143

RESUMO

The paramount concerns of global warming, fossil fuel depletion, and energy crises have prompted the need of hydrocarbons productions via CO2 conversion. In order to achieve global carbon neutrality, much attention needs to be diverted towards CO2 management. Catalytic hydrogenation of CO2 is an exciting opportunity to curb the increasing CO2 and produce value-added products. However, the comprehensive understanding of CO2 hydrogenation is still a matter of discussion due to its complex reaction mechanism and involvement of various species. This review comprehensively discusses three processes: reverse water gas shift (RWGS) reaction, modified Fischer Tropsch synthesis (MFTS), and methanol-mediated route (MeOH) for CO2 hydrogenation to hydrocarbons. Along with analysing the reaction pathways, it is also very important to understand the real-time evolvement of catalytic process and reaction intermediates by employing in-situ characterization techniques under actual reaction conditions. Subsequently, in second part of this review, we provided a systematic analysis of advancements in in-situ techniques aimed to monitor the evolution of catalysts during CO2 reduction process. The section also highlights the key components of in-situ cells, their working principles, and applications in identifying reaction mechanisms for CO2 hydrogenation. Finally, by reviewing respective achievements in the field, we identify key gaps and present some future directions for CO2 hydrogenation and in-situ studies.

8.
ChemSusChem ; : e202400602, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760993

RESUMO

The selective hydrogenation of biomass derivatives presents a promising pathway for the production of high-value chemicals and fuels, thereby reducing reliance on traditional petrochemical industries. Recent strides in catalyst nanostructure engineering, achieved through tailored support properties, have significantly enhanced the hydrogenation performance in biomass upgrading. A comprehensive understanding of biomass selective upgrading reactions and the current advancement in supported catalysts is crucial for guiding future processes in renewable biomass. This review aims to summarize the development of supported nanocatalysts for the selective hydrogenation of the US DOE's biomass platform compounds derivatives into valuable upgraded molecules. The discussion includes an exploration of the reaction mechanisms and conditions in catalytic transfer hydrogenation (CTH) and high-pressure hydrogenation. By thoroughly examining the tailoring of supports, such as metal oxide catalysts and porous materials, in nano-supported catalysts, we elucidate the promoting role of nanostructure engineering in biomass hydrogenation. This endeavor seeks to establish a robust theoretical foundation for the fabrication of highly efficient catalysts. Furthermore, the review proposes prospects in the field of biomass utilization and address application bottlenecks and industrial challenges associated with the large-scale utilization of biomass.

9.
Gene ; 925: 148591, 2024 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-38788818

RESUMO

Primary liver cancer has consistently exhibited a high prevalence and fatality rate, necessitating the investigation of associated diagnostic markers and inhibition mechanisms to effectively mitigate its impact. The significance of apolipoprotein M (ApoM) in impeding the progression of neoplastic ailments is progressively gaining recognition. However, a comprehensive understanding of its underlying mechanism in liver cancer advancement remains to be elucidated. Recent evidence indicates a potential association between ApoM and polyunsaturated fatty acids (PUFAs), with the peroxidation of phospholipids (PLs) containing PUFAs being recognized as a crucial element in the occurrence of ferroptosis. This prompts us to investigate the impact of the APOM gene on the progression of liver cancer through the ferroptosis pathway and elucidate its underlying mechanisms. The findings of this study indicate that the liver cancer cell model, which was genetically modified to overexpress the APOM gene, demonstrated a heightened ferroptosis effect. Moreover, the observed inhibition of the GSH (Glutathione) - GPX4 (Glutathione Peroxidase 4) regulatory axis suggests that the role of this axis in inhibiting ferroptosis is weakened. Through intersection screening and validation, we found that Mucin 1,cell surface associated (MUC1) can inhibit ferroptosis and is regulated by the APOM gene. Bioinformatics analysis and screening identified miR-4489 as a mediator between the two. Experimental results using the dual luciferase reporter gene confirmed that has-miR-4489 targets MUC1's 3'-UTR and inhibits its expression. In conclusion, this study provides evidence that the APOM gene induces a down-regulation in the expression of the ferroptosis-inhibiting gene MUC1, mediated by miR-4489, thereby impeding the advancement of liver cancer cells through the facilitation of ferroptosis.


Assuntos
Apolipoproteínas M , Carcinoma Hepatocelular , Ferroptose , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas , MicroRNAs , Ferroptose/genética , Humanos , Apolipoproteínas M/genética , Apolipoproteínas M/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Linhagem Celular Tumoral , Células Hep G2
10.
Nat Commun ; 15(1): 2718, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548724

RESUMO

Unraveling the effect of spatially separated bifunctional sites on catalytic reactions is significant yet challenging. In this report, we investigate the role of spatial separation on the oxidation of methane in a series of Cu-exchanged aluminosilicate zeolites. Regulation of the bifunctional sites is done either through studying a physical mixture of Cu-exchanged zeolites and acidic zeolites or by systematically varying the Cu and acid density within a family of zeolite materials. We show that separated Cu and acid sites are beneficial for the formation of hydrocarbons while high-density Cu sites, which are closer together, facilitate the production of CO2. By contrast, a balance of the spatial separation of Cu and acid sites shows more favorable formation of methanol. This work will further guide approaches to methane oxidation to methanol and open an avenue for promoting hydrocarbon synthesis using methanol as an intermediate.

11.
ACS Appl Mater Interfaces ; 16(10): 13234-13246, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38411590

RESUMO

Carnitine palmitoyltransferase 1A (CPT1A), which resides on the mitochondrial outer membrane, serves as the rate-limiting enzyme of fatty acid ß-oxidation. Identifying the compounds targeting CPT1A warrants a promising candidate for modulating lipid metabolism. In this study, we developed a CPT1A-overexpressed mitochondrial membrane chromatography (MMC) to screen the compounds with affinity for CPT1A. Cells overexpressing CPT1A were cultured, and subsequently, their mitochondrial membrane was isolated and immobilized on amino-silica gel cross-linked by glutaraldehyde. After packing the mitochondrial membrane column, retention components of MMC were performed with LC/MS, whose analytic peaks provided structural information on compounds that might interact with mitochondrial membrane proteins. With the newly developed MMC-LC/MS approach, several Chinese traditional medicine extracts, such as Scutellariae Radix and Polygoni Cuspidati Rhizoma et Radix (PCRR), were analyzed. Five noteworthy compounds, baicalin, baicalein, wogonoside, wogonin, and resveratrol, were identified as enhancers of CPT1A enzyme activity, with resveratrol being a new agonist for CPT1A. The study suggests that MMC serves as a reliable screening system for efficiently identifying modulators targeting CPT1A from complex extracts.


Assuntos
Carnitina O-Palmitoiltransferase , Metabolismo dos Lipídeos , Carnitina O-Palmitoiltransferase/genética , Carnitina O-Palmitoiltransferase/química , Carnitina O-Palmitoiltransferase/metabolismo , Resveratrol , Membranas Mitocondriais , Cromatografia
12.
Brief Bioinform ; 25(1)2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-38048081

RESUMO

Identifying task-relevant structures is important for molecular property prediction. In a graph neural network (GNN), graph pooling can group nodes and hierarchically represent the molecular graph. However, previous pooling methods either drop out node information or lose the connection of the original graph; therefore, it is difficult to identify continuous subtructures. Importantly, they lacked interpretability on molecular graphs. To this end, we proposed a novel Molecular Edge Shrinkage Pooling (MESPool) method, which is based on edges (or chemical bonds). MESPool preserves crucial edges and shrinks others inside the functional groups and is able to search for key structures without breaking the original connection. We compared MESPool with various well-known pooling methods on different benchmarks and showed that MESPool outperforms the previous methods. Furthermore, we explained the rationality of MESPool on some datasets, including a COVID-19 drug dataset.


Assuntos
COVID-19 , Aprendizado Profundo , Humanos , Redes Neurais de Computação , Benchmarking
13.
J Am Chem Soc ; 145(37): 20365-20374, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37671920

RESUMO

This study reports the successful development of a sustainable synthesis protocol for a phase-pure metal azolate framework (MAF-6) and its application in enzyme immobilization. An esterase@MAF-6 biocomposite was synthesized, and its catalytic performance was compared with that of esterase@ZIF-8 and esterase@ZIF-90 in transesterification reactions. Esterase@MAF-6, with its large pore aperture, showed superior enzymatic performance compared to esterase@ZIF-8 and esterase@ZIF-90 in catalyzing transesterification reactions using both n-propanol and benzyl alcohol as reactants. The hydrophobic nature of the MAF-6 platform was shown to activate the immobilized esterase into its open-lid conformation, which exhibited a 1.5- and 4-times enzymatic activity as compared to free esterase in catalyzing transesterification reaction using n-propanol and benzyl alcohol, respectively. The present work offers insights into the potential of MAF-6 as a promising matrix for enzyme immobilization and highlights the need to explore MOF matrices with expanded pore apertures to broaden their practical applications in biocatalysis.


Assuntos
1-Propanol , Carboxilesterase , Esterases , Álcool Benzílico
14.
JACS Au ; 3(9): 2586-2596, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37772179

RESUMO

Solid acid catalysts with bi-acidity are promising as workhouse catalysts in biorefining to produce high-quality chemicals and fuels. Herein, we report a new strategy to develop bi-acidic cascade catalysts by separating both acid sites in geometry via the atomic layer deposition (ALD) of Lewis acidic alumina on Brønsted acidic supports. Visualized by transmission electron microscopy and electron energy loss spectroscopy mapping, the ALD-deposited alumina forms a conformal alumina domain with a thickness of around 3 nm on the outermost surface of mesoporous silica-alumina. Solid state nuclear magnetic resonance investigation shows that the dominant Lewis acid sites distribute on the outermost surface, whereas intrinsic Brønsted acid sites locate inside the nanopores within the silica-rich substrate. In comparison to other bi-acidic solid catalyst counterparts, the special geometric distance of Lewis and Brønsted acid sites minimized the synergetic effect, leading to a cascade reaction environment. For cascade glucose conversion, the designed ALD catalyst showed a highly enhanced catalytic performance.

15.
FEBS J ; 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37221945

RESUMO

As a self-degrading and highly conserved survival mechanism, autophagy plays an important role in maintaining cell survival and recycling. The discovery of autophagy-related (ATG) genes has revolutionized our understanding of autophagy. Lysosomal membrane proteins (LMPs) are important executors of lysosomal function, and increasing evidence has demonstrated their role in the induction and regulation of autophagy. In addition, the functional dysregulation of the process mediated by LMPs at all stages of autophagy is closely related to neurodegenerative diseases and cancer. Here, we review the role of LMPs in autophagy, focusing on their roles in vesicle nucleation, vesicle elongation and completion, the fusion of autophagosomes and lysosomes, and degradation, as well as their broad association with related diseases.

16.
Chemistry ; 29(31): e202300543, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-36891991

RESUMO

The usage of hierarchical MFI zeolite enables a boost of the catalytic performance of Mo-based catalysts for the olefin-metathesis reaction. The harvest of active catalysts roots in a segmental evolution track between hierarchical zeolite and Al2 O3 slices for the fabrication of active sites. The working evolution track requires the indispensable engagements from intracrystalline mesoporous surface, Al2 O3 slices, and zeolitic Brønsted acid sites. The infilling of disaggregated Al2 O3 slices into the intracrystalline mesopores triggers the creation of localized intrazeolite-Al2 O3 interfaces, which enables the subsequent migration and trapping of surface molybdates into the micropores. The insulation of intrazeolite-Al2 O3 interface or shielding of zeolitic Brønsted acid sites leads to the break of the evolution track. Our findings disclose the hidden functionality of mesoporosity as intrazeolite interface boundary for the fabrication of active sites and supply a new strategy for the rational design of zeolite catalysts.

17.
FEBS J ; 290(19): 4626-4637, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36176242

RESUMO

The SID1 transmembrane family, member 2, namely, Sidt2, is a highly glycosylated multichannel lysosomal transmembrane protein, but its specific physiological function remains unknown. Lysosomal membrane proteins are very important for the executive functioning of lysosomes. As an important part of the lysosomal membrane, Sidt2 can maintain the normal morphology of lysosomes and help stabilize them from the acidic pH environment within. As a receptor/transporter, it binds and transports nucleic acids and mediates the uptake and degradation of RNA and DNA by the lysosome. During glucose metabolism, deletion of Sidt2 can cause an increase in fasting blood glucose and the impairment of grape tolerance, which is closely related to the secretion of insulin. During lipid metabolism, the loss of Sidt2 can cause hepatic steatosis and lipid metabolism disorders and can also play a role in signal regulation and transport. Here, we review the function of the lysosomal membrane protein Sidt2, and focus on its role in glucose and lipid metabolism, autophagy and nucleotide (DNA/RNA) transport.


Assuntos
Proteínas de Membrana , RNA , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , RNA/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Lisossomos/metabolismo , Proteínas de Membrana Lisossomal/metabolismo , DNA/metabolismo , Autofagia
18.
Cell Death Dis ; 13(1): 7, 2021 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-34923568

RESUMO

The regulation and homeostasis of autophagy are essential for maintaining organ morphology and function. As a lysosomal membrane protein, the effect of Sidt2 on kidney structure and renal autophagy is still unknown. In this study, we found that the kidneys of Sidt2-/- mice showed changes in basement membrane thickening, foot process fusion, and mitochondrial swelling, suggesting that the structure of the kidney was damaged. Increased urine protein at 24 h indicated that the kidney function was also damaged. At the same time, the absence of Sidt2 caused a decrease in the number of acidic lysosomes, a decrease in acid hydrolase activity and expression in the lysosome, and an increase of pH in the lysosome, suggesting that lysosomal function was impaired after Sidt2 deletion. The accumulation of autophagolysosomes, increased LC3-II and P62 protein levels, and decreased P62 mRNA levels indicated that the absence of the Sidt2 gene caused abnormal autophagy pathway flow. Chloroquine experiment, immunofluorescence autophagosome, and lysosome fusion assay, and Ad-mcherry-GFP-LC3B further indicated that, after Sidt2 deletion, the production of autophagosomes did not increase, but the fusion of autophagosomes and lysosomes and the degradation of autophagolysosomes were impaired. When incubating Sidt2-/- cells with the autophagy activator rapamycin, we found that it could activate autophagy, which manifested as an increase in autophagosomes, but it could not improve autophagolysosome degradation. Meanwhile, it further illustrated that the Sidt2 gene plays an important role in the smooth progress of autophagolysosome processes. In summary, the absence of the Sidt2 gene caused impaired lysosome function and a decreased number of acidic lysosomes, leading to formation and degradation disorders of the autophagolysosomes, which eventually manifested as abnormal kidney structure and function. Sidt2 is essential in maintaining the normal function of the lysosomes and the physiological stability of the kidneys.


Assuntos
Lisossomos/metabolismo , Proteínas de Transporte de Nucleotídeos/metabolismo , Animais , Autofagia , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Transfecção
19.
FASEB J ; 35(10): e21848, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34582051

RESUMO

Lysosomes have long been regarded as the "garbage dump" of the cell. More recently, however, researchers have revealed novel roles for lysosomal membranes in autophagy, ion transport, nutrition sensing, and membrane fusion and repair. With active research into lysosomal membrane proteins (LMP), increasing evidence has become available showing that LMPs are inextricably linked to glucose and lipid metabolism, and this relationship represents mutual influence and regulation. In this review, we summarize the roles of LMPs in relation to glucose and lipid metabolism, and describe their roles in glucose transport, glycolysis, cholesterol transport, and lipophagy. The role of transport proteins can be traced back to the original discoveries of GLUT8, NPC1, and NPC2, which were all found to have significant roles in the pathways involved in glucose and lipid metabolism. CLC-5 and SIDT2-knockout animals show serious phenotypic disorders of metabolism, and V-ATPase and LAMP-2 have been found to interact with proteins related to glucose and lipid metabolism. These findings all emphasize the critical role of LMPs in glycolipid metabolism and help to strengthen our understanding of the independent and close relationship between LMPs and glycolipid metabolism.


Assuntos
Glucose/metabolismo , Metabolismo dos Lipídeos , Proteínas de Membrana Lisossomal/metabolismo , Animais , Humanos
20.
JACS Au ; 1(3): 262-271, 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-34467291

RESUMO

Amorphous silica-aluminas (ASAs) are important solid catalysts and supports for many industrially essential and sustainable processes, such as hydrocarbon transformation and biorefining. However, the wide distribution of acid strength on ASAs often results in undesired side reactions, lowering the product selectivity. Here we developed a strategy for the synthesis of a unique class of ASAs with unvarying strength of Brønsted acid sites (BAS) and Lewis acid sites (LAS) using double-flame-spray pyrolysis. Structural characterization using high-resolution transmission electron microscopy (TEM) and solid-state nuclear magnetic resonance (NMR) spectroscopy showed that the uniform acidity is due to a distinct nanostructure, characterized by a uniform interface of silica-alumina and homogeneously dispersed alumina domains. The BAS population density of as-prepared ASAs is up to 6 times higher than that obtained by classical methods. The BAS/LAS ratio, as well as the population densities of BAS and LAS of these ASAs, could be tuned in a broad range. In cyclohexanol dehydration, the uniform Brønsted acid strength provides a high selectivity to cyclohexene and a nearly linear correlation between acid site densities and cyclohexanol conversion. Moreover, the concerted action of these BAS and LAS leads to an excellent bifunctional Brønsted-Lewis acid catalyst for glucose dehydration, affording a superior 5-hydroxymethylfurfural yield.

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