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1.
Chemphyschem ; 24(9): e202200947, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36715013

RESUMO

Planar, tubular, cage-like, and bilayer boron clusters Bn +/0/- (n=3∼48) have been observed in joint experimental and theoretical investigations in the past two decades. Based on extensive global searches augmented with first-principles theory calculations, we predict herein the smallest perfect core-shell octahedral borospherene Oh B@B38 + (1) and its endohedral metallo-borospherene analogs Oh Be@B38 (2), and Oh Zn@B38 (3) which, with an octa-coordinate B, Be or Zn atom located exactly at the center, turn out to be the well-defined global minima of the systems highly stable both thermodynamically and dynamically. B@B38 + (1) represents the first boron-containing molecule reported to date which contains an octa-coordinate B center covalently coordinated by eight face-capping boron atoms at the corners of a perfect cube in the first coordination sphere. Detailed natural bonding orbital (NBO) and adaptive natural density partitioning (AdNDP) bonding analyses indicate that these high-symmetry core-shell complexes X@B38 +/0/- (X=B, Be, Zn) as super-noble gas atoms follow the octet rule in coordination bonding patterns (1S2 1P6 ), with one delocalized 9c-2e S-type coordination bond and three delocalized 39c-2e P-type coordination bonds formed between the octa-coordinate X center and its octahedral Oh B38 ligand to effectively stabilize the systems. Their IR, Raman, and UV-Vis spectra are computationally simulated to facilitate their spectroscopic characterizations.

2.
Chemphyschem ; 24(9): e202300222, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37129295

RESUMO

The front cover artwork is provided by Prof. Si-Dian Li's group at Shanxi University, China. The image shows the smallest perfect core-shell octahedral borospherene Oh B@B38 + and its endohedral metallo-borospherene analogs Oh Be@B38 and Oh Zn@B38 obtained at first-principles theory. Read the full text of the Research Article at 10.1002/cphc.202200947.

3.
Molecules ; 28(9)2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37175301

RESUMO

Transition-metal-doped boron nanoclusters exhibit unique structures and bonding in chemistry. Using the experimentally observed seashell-like borospherenes C2 B28-/0 and Cs B29- as ligands and based on extensive first-principles theory calculations, we predict herein a series of novel transition-metal-centered endohedral seashell-like metallo-borospherenes C2 Sc@B28- (1), C2 Ti@B28 (2), C2 V@B28+ (3), and Cs V@B292- (4) which, as the global minima of the complex systems, turn out to be the boron analogues of dibenzenechromium D6h Cr(C6H6)2 with two B12 ligands on the top and bottom interconnected by four or five corner boron atoms on the waist and one transition-metal "pearl" sandwiched at the center in between. Detailed molecular orbital, adaptive natural density partitioning (AdNDP), and iso-chemical shielding surface (ICSS) analyses indicate that, similar to Cr(C6H6)2, these endohedral seashell-like complexes follow the 18-electron rule in bonding patterns (1S21P61D10), rendering spherical aromaticity and extra stability to the systems.

4.
Acta Biomater ; 181: 308-316, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38570107

RESUMO

Acute lung injury (ALI) represents a critical respiratory condition typified by rapid-onset lung inflammation, contributing to elevated morbidity and mortality rates. Central to ALI pathogenesis lies macrophage dysfunction, characterized by an overabundance of pro-inflammatory cytokines and a shift in metabolic activity towards glycolysis. This study emphasizes the crucial function of glucose metabolism in immune cell function under inflammatory conditions and identifies hexokinase 2 (HK2) as a key regulator of macrophage metabolism and inflammation. Given the limitations of HK2 inhibitors, we propose the CRISPR/Cas9 system for precise HK2 downregulation. We developed an aerosolized core-shell liposomal nanoplatform (CSNs) complexed with CaP for efficient drug loading, targeting lung macrophages. Various CSNs were synthesized to encapsulate an mRNA based CRISPR/Cas9 system (mCas9/gHK2), and their gene editing efficiency and HK2 knockout were examined at both gene and protein levels in vitro and in vivo. The CSN-mCas9/gHK2 treatment demonstrated a significant reduction in glycolysis and inflammation in macrophages. In an LPS-induced ALI mouse model, inhaled CSN-mCas9/gHK2 mitigated the proinflammatory tumor microenvironment and reprogrammed glucose metabolism in the lung, suggesting a promising strategy for ALI prevention and treatment. This study highlights the potential of combining CRISPR/Cas9 gene editing with inhalation delivery systems for effective, localized pulmonary disease treatment, underscoring the importance of targeted gene modulation and metabolic reprogramming in managing ALI. STATEMENT OF SIGNIFICANCE: This study investigates an inhalable CRISPR/Cas9 gene editing system targeting pulmonary macrophages, with the aim of modulating glucose metabolism to alleviate Acute Lung Injury (ALI). The research highlights the role of immune cell metabolism in inflammation, as evidenced by changes in macrophage glucose metabolism and a notable reduction in pulmonary edema and inflammation. Additionally, observed alterations in macrophage polarization and cytokine levels in bronchoalveolar lavage fluid suggest potential therapeutic implications. These findings not only offer insights into possible ALI treatments but also contribute to the understanding of immune cell metabolism in inflammatory diseases, which could be relevant for various inflammatory and metabolic disorders.


Assuntos
Lesão Pulmonar Aguda , Sistemas CRISPR-Cas , Hexoquinase , Lesão Pulmonar Aguda/patologia , Lesão Pulmonar Aguda/terapia , Animais , Camundongos , Hexoquinase/genética , Hexoquinase/metabolismo , Camundongos Endogâmicos C57BL , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Administração por Inalação , Lipossomos/química , Células RAW 264.7 , Masculino , Reprogramação Celular/efeitos dos fármacos , Edição de Genes , Glicólise/efeitos dos fármacos
5.
Nanoscale ; 14(31): 11443-11451, 2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-35904368

RESUMO

Inspired by the experimentally observed bilayer B48-/0 and theoretically predicted bilayer B50-B72 and based on extensive density functional theory calculations, we report herein a series of novel medium-sized bilayer boron nanoclusters C1 B84 (I), C2v B86 (II), C1 B88 (III), C1 B90 (IV), C1 B92 (V), C1 B94 (VI), C2v B96 (VII), and C1 B98 (VIII) which are the most stable isomers of the systems reported to date effectively stabilized by optimum numbers of interlayer B-B σ bonds between the inward-buckled atoms on top and bottom layers. Detailed bonding analyses indicate that these bilayer species follow the universal bonding pattern of σ + π double delocalization, rendering three-dimensional aromaticity in the systems. More interestingly, the AA-stacked bilayer structural motif in B96 (VII) with a B72 bilayer hexagonal prism at the center can be extended to form bilayer C2 B128 (IX), D2h B214 (X), C2v B260 (XI), D2h B372 (XII), and D2 B828 (XIII) which contain one or multiple conjoined B72 bilayer hexagonal prisms sharing interwoven zig-zag boron triple chains between them. Such bilayer species or their close-lying AB isomers can be viewed as embryos of the newly reported most stable freestanding BL-α+ bilayer borophenes and quasi-freestanding bilayer borophenes on Ag(111) which are composed of interwoven zig-zag boron triple chains shared by conjoined BL B72 hexagonal prisms, presenting a bottom-up approach from medium-sized bilayer boron nanoclusters to two-dimensional bilayer borophene nanomaterials.

6.
Commun Chem ; 5(1): 25, 2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36697605

RESUMO

Despite its electron deficiency, boron can form multiple bonds with a variety of elements. However, multiple bonds between boron and main-group metal elements are relatively rare. Here we report the observation of boron-lead multiple bonds in PbB2O- and PbB3O2-, which are produced and characterized in a cluster beam. PbB2O- is found to have an open-shell linear structure, in which the bond order of B☱Pb is 2.5, while the closed-shell [Pb≡B-B≡O]2- contains a B≡Pb triple bond. PbB3O2- is shown to have a Y-shaped structure with a terminal B = Pb double bond coordinated by two boronyl ligands. Comparison between [Pb≡B-B≡O]2-/[Pb=B(B≡O)2]- and the isoelectronic [Pb≡B-C≡O]-/[Pb=B(C≡O)2]+ carbonyl counterparts further reveals transition-metal-like behaviors for the central B atoms. Additional theoretical studies show that Ge and Sn can form similar boron species as Pb, suggesting the possibilities to synthesize new compounds containing multiple boron bonds with heavy group-14 elements.

7.
J Mol Model ; 27(12): 364, 2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34842972

RESUMO

The successive experimental observations of planar, cage-like, seashell-like, and bilayer Bn-/0 clusters in the size range between n = 3-48 well demonstrate the structural diversity and rich chemistry of boron nanoclusters. Based on extensive global minimum search and density functional theory calculations, we predict herein the bilayer C1 B50 (I), C2h B52 (II), C1 B56 (IV), and C2v B58 (V) as the global minima of the systems to fill in the missing gap in the bilayer B2n series between B48-B72. These highly stable species all contain a B38 bilayer hexagonal prism at the center, with 2, 2, 3, and 3 effective interlayer B-B σ-bonds formed between inward-buckled atoms on the top and bottom layers, respectively. Our bilayer C1 B50 (I) and C1 B56 (IV) prove to be obviously more stable than the previously reported quasi-planar C2v B50 and C2v B56 with two adjacent B6 hexagonal holes. Detailed bonding analyses indicate that these bilayer clusters follow the universal bonding pattern of σ + π double delocalization, making them three-dimensionally aromatic in nature. The bilayer B2n species in the size range between B48-B72 evolve gradually on the waist around the B38 or elongated B46 bilayer hexagonal prism at the center.

8.
Oxid Med Cell Longev ; 2019: 5847040, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31885805

RESUMO

Resveratrol (RES), a dietary polyphenol compound, has been shown to possess health benefits due to its anti-inflammatory, antioxidative, and antiatherosclerosis properties. Tryptophan metabolite-derived indoxyl sulfate (IS) is identified as one of the uremic toxins and physiological endogenous ligand/activator of aryl hydrocarbon receptor (AHR), associated with atherosclerosis in chronic kidney disease (CKD) patients. Studies have shown that a high serum level of IS causes deleterious effects on health primarily by inducing oxidative stress and endothelial dysfunction. However, the precise mechanisms are still unclear. Here, we investigated the underlying mechanism of IS effect on endothelial permeability and the role of RES on IS-induced endothelial hyperpermeability via the AHR/Src-dependent pathway. Bovine aorta endothelial cells (BAECs) were cultured and incubated with IS in the presence or absence of RES, and transendothelial electrical resistance (TEER) and permeability of cells were measured. Alongside, AHR, Src kinase, and Vascular Endothelial Cadherin (VE-Cadherin) activation were examined. Our data showed that IS reduced TEER of cells resulting in increased permeability. VE-Cadherin, a vital regulator of endothelial permeability, was also significantly activated in response to IS, which appeared to be associated with changes of endothelial permeability and AHR/Src kinase. Interestingly, in this setting, RES reversed the effect of IS and inhibited the increased activation of Src induced by IS-activated AHR and modulated VE-Cadherin and permeability. CH223191, an inhibitor of AHR, significantly inhibits IS-induced endothelial hyperpermeability. Further analysis with treatment of PP2, an inhibitor of Src abolishing Src activation, suggests downstream factors. All our data indicated that IS upregulated the AHR/Src kinase pathway, and increased endothelial permeability and phosphorylation of VE-Cadherin may be represented and provide new strategies for addressing protective properties of RES against Src kinase involved in AHR-mediated endothelial hyperpermeability. The findings may be crucial for managing diseases in which endothelial permeability is compromised, and the dietary polyphenols are involved.


Assuntos
Antioxidantes/farmacologia , Aorta/patologia , Aterosclerose/tratamento farmacológico , Células Endoteliais/fisiologia , Receptores de Hidrocarboneto Arílico/metabolismo , Insuficiência Renal Crônica/tratamento farmacológico , Resveratrol/farmacologia , Animais , Antígenos CD/metabolismo , Caderinas/metabolismo , Bovinos , Permeabilidade da Membrana Celular , Células Cultivadas , Impedância Elétrica , Células Endoteliais/patologia , Indicã/metabolismo , Estresse Oxidativo , Transdução de Sinais , Quinases da Família src/metabolismo
9.
PLoS One ; 12(7): e0180865, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28686680

RESUMO

Defective lipid metabolism is associated with increased risk of various chronic diseases, such as obesity, cardiovascular diseases, and diabetes. Resveratrol (RSV), a natural polyphenol, has been shown the potential of ameliorating disregulations of lipid metabolism. The objective of this study was to investigate the effects of feed intake and RSV on lipid metabolism in zebrafish (Danio rerio). The adult males were randomly allocated to 6 groups: control (Con, 8 mg cysts/fish/day), control with 20 µmol/L RSV (Con+RSV), calorie restriction (CR, 5 mg cysts/fish/day), calorie restriction with RSV (CR+RSV), overfeed (OF, 60 mg cysts/fish/day), and overfeed with RSV (OF+RSV) groups. The treatment period was 8 weeks. Results showed that CR reduced body length, body weight, and condition factor of zebrafish. CR reduced levels of plasma triglyceride (TG) and induced protein expression of phosphorylated AMP-activated protein kinase-α (pAMPKα), silent information regulator 2 homolog 1 (Sirt1), and peroxisome proliferator activated receptor gamma coactivator-1α (PGC1α). RSV attenuated CR-induced pAMPKα/AMPKαincreases. RSV increased levels of Sirt1 protein in the OF zebrafish, and decreased OF-induced increase in peroxisome proliferator-activated receptor-γ (PPARγ) protein level. Additionally, RSV down-regulated caveolin-1 and up-regulated microtubule-associated protein 1 light chain 3 -II (LC3-II) protein levels in OF zebrafish. In conclusion, these results suggest that 1) CR reduces plasma TG level through activation of the AMPKα-Sirt1- PGC1α pathway; 2) under different dietary stress conditions RSV might regulate AMPK phosphorylation bi-directionally; 3) RSV might regulate lipid metabolism through the AMPKα-Sirt1-PPARγ pathway in OF zebrafish.


Assuntos
Antioxidantes/farmacologia , Dieta/métodos , Regulação da Expressão Gênica/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Estilbenos/farmacologia , Quinases Proteína-Quinases Ativadas por AMP , Animais , Restrição Calórica/efeitos adversos , Caveolina 1/genética , Caveolina 1/metabolismo , Ingestão de Alimentos/fisiologia , Feminino , Metabolismo dos Lipídeos/genética , Masculino , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Fosforilação , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Resveratrol , Transdução de Sinais , Sirtuína 1/genética , Sirtuína 1/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Triglicerídeos/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
10.
Nutrients ; 9(5)2017 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-28505110

RESUMO

Epidemiological and experimental studies reveal that Western dietary patterns contribute to chronic kidney disease, whereas dietary restriction (DR) or dietary polyphenols such as green tea polyphenols (GTPs) can ameliorate the progression of kidney injury. This study aimed to investigate the renal protective effects of GTPs and explore the underlying mechanisms. Sixty Wistar rats were randomly divided into 6 groups: standard diet (STD), DR, high-fat diet (HFD), and three diets plus 200 mg/kg(bw)/day GTPs, respectively. After 18 weeks, HFD group exhibited renal injuries by increased serum cystatin C levels and urinary N-acetyl-ß-d-glucosaminidase activity, which can be ameliorated by GTPs. Meanwhile, autophagy impairment as denoted by autophagy-lysosome related proteins, including LC3-II, Beclin-1, p62, cathepsin B, cathepsin D and LAMP-1, was observed in HFD group, whereas DR or GTPs promoted renal autophagy activities and GTPs ameliorated HFD-induced autophagy impairment. In vitro, autophagy flux suppression was detected in palmitic acid (PA)-treated human proximal tubular epithelial cells (HK-2), which was ameliorated by epigallocatechin-3-gallate (EGCG). Furthermore, GTPs (or EGCG) elevated phosphorylation of AMP-activated protein kinase in the kidneys of HFD-treated rats and in PA-treated HK-2 cells. These findings revealed that GTPs mimic the effects of DR to induce autophagy and exert a renal protective effect by alleviating HFD-induced autophagy suppression.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Autofagia/efeitos dos fármacos , Polifenóis/farmacologia , Chá/química , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Antioxidantes/farmacologia , Glicemia/metabolismo , Catequina/análogos & derivados , Catequina/farmacologia , Linhagem Celular , Colesterol/sangue , Creatinina/sangue , Creatinina/urina , Cistatina C/sangue , Dieta Hiperlipídica/efeitos adversos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Fosforilação , Ratos , Ratos Wistar , Triglicerídeos/sangue
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