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1.
Chemistry ; 29(9): e202203189, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36401594

RESUMO

Arene hydrogenation is the most straightforward method to prepare carbo- and heterocycles. However, the high resonance energy prevents aromatic substrates from hydrogenation. Herein the homogeneous, nucleophilic hydrogenation of less electron-rich arenes and heteroarenes is reported. The Co(P4 N2 )H species that has been demonstrated to be a strong hydride donor could deliver a hydride ion to the cyano (hetero)arene substrates. Deuterium labeling experiments supported a Michael-type reaction pathway. Theoretical analyses have been conducted to investigate the hydricity of the catalytically active CoH species and the electrophilicity of the arene substrates. An outlook for the synthesis of more challenging substituted benzenes was proposed based on the in silico modification of the CoH species.

2.
J Org Chem ; 88(3): 1504-1514, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36660775

RESUMO

It is highly desirable to avoid using rare or toxic metals for oxidative reactions in the synthesis of pharmaceuticals and fine chemicals. Hypervalent iodine compounds are environmentally benign alternatives, but their catalytic use has been quite limited. Herein, the protocol for in situ hypoiodite-catalyzed oxidative rearrangement of chalcones is first realized under mild and metal-free conditions, which provided a nontoxic, environmental-benign, and catalytic alternative to the thallium-based protocol. Also, the applicability and effectiveness of this catalytic protocol got well demonstrated via gram-scale synthesis and product derivatization. What is more, control and NMR tracking experiments were performed to figure out the possible catalytic species and intermediates.

3.
Water Sci Technol ; 87(4): 834-851, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36853765

RESUMO

The experimental and theoretical studies on the adsorption of Cu(II) on the surface of Na-montmorillonite (Na-Mt) were reported. Effects of batch adsorption experimental parameters were studied. Density functional theory and molecular dynamics simulations were used to study the adsorption of Cu(II) on montmorillonite (001) surface. The adsorption reached equilibrium within 80 min and the adsorption capacity was 35.23 mg·g-1 at 25 °C. The adsorption data of Cu(II) were consistent with pseudo-second-order kinetics and Langmuir isotherm models. The adsorption process was dominated by physical adsorption (Ea was 37.08 kJ·mol-1) with spontaneous endothermic behavior. The influence of coexisting cations on the adsorption capacity of Cu(II) was Mg(II) > Co(II) > Ca(II) > Na(I). The simulation results demonstrated that there were no significant differences in the adsorption energy of Cu(II) at the four adsorption sites on the montmorillonite (001) surface. Cu(II) had more electron transfer than Na(I). The diffusion coefficient of Cu(II) in the aqueous solution system containing montmorillonite was 0.85×10-10 m2·s-1. Considerable amounts of Cu(II) ions were adsorbed at a distance of 0.26 and 2.25 Å from the montmorillonite (001) surface. The simulation results provided strong supporting evidence for experimental conclusions.


Assuntos
Bentonita , Íons , Adsorção , Simulação por Computador , Cinética
4.
BMC Genomics ; 23(1): 484, 2022 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35780085

RESUMO

BACKGROUND: Apple replant disease is a soilborne disease caused by Fusarium proliferatum f. sp. malus domestica strain MR5 (abbreviated hereafter as Fpmd MR5) in China. This pathogen causes root tissue rot and wilting leaves in apple seedlings, leading to plant death. A comparative transcriptome analysis was conducted using the Illumina Novaseq platform to identify the molecular defense mechanisms of the susceptible M.26 and the resistant M9T337 apple rootstocks to Fpmd MR5 infection. RESULTS: Approximately 518.1 million high-quality reads were generated using RNA sequencing (RNA-seq). Comparative analysis between the mock-inoculated and Fpmd MR5 infected apple rootstocks revealed 28,196 significantly differentially expressed genes (DEGs), including 14,572 up-regulated and 13,624 down-regulated genes. Among them, the transcriptomes in the roots of the susceptible genotype M.26 were reflected by overrepresented DEGs. MapMan analysis indicated that a large number of DEGs were involved in the response of apple plants to Fpmd MR5 stress. The important functional groups identified via gene ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment were responsible for fundamental biological regulation, secondary metabolism, plant-pathogen recognition, and plant hormone signal transduction (ethylene and jasmonate). Furthermore, the expression of 33 up-regulated candidate genes (12 related to WRKY DNA-binding proteins, one encoding endochitinase, two encoding beta-glucosidases, ten related to pathogenesis-related proteins, and eight encoding ethylene-responsive transcription factors) were validated by quantitative real-time PCR. CONCLUSION: RNA-seq profiling was performed for the first time to analyze response of apple root to Fpmd MR5 infection. We found that the production of antimicrobial compounds and antioxidants enhanced plant resistance to pathogens, and pathogenesis-related protein (PR10 homologs, chitinase, and beta-glucosidase) may play unique roles in the defense response. These results provide new insights into the mechanisms of the apple root response to Fpmd MR5 infection.


Assuntos
Malus , Etilenos , Fusarium , Regulação da Expressão Gênica de Plantas , Malus/genética , Doenças das Plantas/genética , Transcriptoma
5.
J Org Chem ; 87(24): 16941-16946, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36473047

RESUMO

Converting cheap and abundant internal alkenes to value-added linear aldehydes is of great importance but not an addressed issue. In this paper, an integration of a Milstein-type Ru-PNN catalyst and our Rh-Tribi/Tetrabi catalyst was first demonstrated in highly improved isomerization linear selective hydroformylation of 2-, 3-, and 4-alkenes, yielding excellent linear selectivities and activities (linear selectivity improvements of 2.2-58%, up to 94.2-98.6%, and turnover numbers improvements of 61-335 TON, up to 385-851) compared to the Ru-PNN/Rh-Bisbi system.

6.
Int J Health Plann Manage ; 37(5): 2918-2935, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35709332

RESUMO

Reducing health inequality and ensuring national health equity have become issues of great concern to all countries in the world. This paper based on the ordered Probit model and concentrated index decomposition method, analysed the influencing factors and evolution trend of health inequality among the elderly with high age in China from 2005 to 2017. The study found that in 2005-2017, the self-rated health distribution of the elderly with high age in China showed an obvious inverted "U" shape, with the proportion of general and relatively healthy being the largest, while the proportion of unhealthy and very healthy was lower. Lifestyle, family income, and age were the main important factors to expand health inequality. Therefore, encouraging the elderly with high age to develop good living habits and narrowing the income gap of the elderly are conducive to solving the health inequality of the elderly with high age and achieving the goals of active ageing and healthy ageing.


Assuntos
Disparidades nos Níveis de Saúde , Renda , Idoso , Envelhecimento , China , Nível de Saúde , Humanos , Fatores Socioeconômicos
7.
Proteome Sci ; 19(1): 2, 2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33446211

RESUMO

BACKGROUND: Apple replant disease (ARD) has been reported from all major fruit-growing regions of the world, and is often caused by biotic factors (pathogen fungi) and abiotic factors (phenolic compounds). In order to clarify the proteomic differences of Fusarium moniliforme under the action of phloridzin, and to explore the potential mechanism of F. moniliforme as the pathogen of ARD, the role of Fusarium spp. in ARD was further clarified. METHODS: In this paper, the quantitative proteomics method iTRAQ analysis technology was used to analyze the proteomic differences of F. moniliforme before and after phloridzin treatment. The differentially expressed protein was validated by qRT-PCR analysis. RESULTS: A total of 4535 proteins were detected, and 293 proteins were found with more than 1.2 times (P< 0.05) differences. In-depth data analysis revealed that 59 proteins were found with more than 1.5 times (P< 0.05) differences, and most proteins were consistent with the result of qRT-PCR. Differentially expressed proteins were influenced a variety of cellular processes, particularly metabolic processes. Among these metabolic pathways, a total of 8 significantly enriched KEGG pathways were identified with at least 2 affiliated proteins with different abundance in conidia and mycelium. Functional pathway analysis indicated that up-regulated proteins were mainly distributed in amino sugar, nucleotide sugar metabolism, glycolysis/ gluconeogenesis and phagosome pathways. CONCLUSIONS: This study is the first to perform quantitative proteomic investigation by iTRAQ labeling and LC-MS/MS to identify differentially expressed proteins in F. moniliforme under phloridzin conditions. The results confirmed that F. moniliforme presented a unique protein profile that indicated the adaptive mechanisms of this species to phloridzin environments. The results deepened our understanding of the proteome in F. moniliforme in response to phloridzin inducers and provide a basis for further exploration for improving the efficiency of the fungi as biocontrol agents to control ARD.

8.
Acta Pharmacol Sin ; 42(6): 964-974, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32934347

RESUMO

Beige adipocytes have been considered as a potential strategy in anti-obesity therapy because of its thermogenic capacity. AMP-activated protein kinase (AMPK) plays important roles in regulating adipose tissue function. C29 is a novel pyrazolone derivative with AMPK activity. In the current study, we investigated the role of C29 in the regulation of thermogenesis using differentiated adipocytes and diet-induced obese mice, and explored the mechanisms that might be involved in energy expenditure via adipocyte AMPK activation. We showed that treatment with C29 (2.5-10 µM) concentration-dependently increased thermogenesis in differentiated preadipocytes separated from inguinal white adipose tissue (iWAT), evidenced by increased expression levels of thermogenesis markers such as Ucp1, Pgc-1α, Dio2, Prdm16, Cox7a1, Cox8b, Elovl3, and Cidea, fatty acid oxidation (FAO) genes including Cpt1a, Lcad and Pparα, as well as beige-selective genes such as Cd137, Tmem26, Slc27a1, and Tbx1. In high-fat diet (HFD)-fed mice, oral administration of C29 (30 mg·kg-1·day-1) for 9 weeks alleviated HFD-induced obesity, promoted energy expenditure and modulated iWAT browning. However, these effects were not observed in adipose-specific AMPKα1/α2 knockout (AKO) mice following C29 administration. Together, this study demonstrates that C29 regulates energy balance via adipocyte AMPK. Our findings show that the discovery of AMPK activators that specifically target adipose tissue may have therapeutic potential for treating obesity-related metabolic diseases.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Ativadores de Enzimas/uso terapêutico , Obesidade/tratamento farmacológico , Pirazolonas/uso terapêutico , Adipócitos/efeitos dos fármacos , Tecido Adiposo Bege/enzimologia , Tecido Adiposo Bege/metabolismo , Tecido Adiposo Branco/enzimologia , Tecido Adiposo Branco/metabolismo , Animais , Temperatura Corporal/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Dieta Hiperlipídica , Resistência à Insulina/fisiologia , Masculino , Camundongos Endogâmicos C57BL , Obesidade/enzimologia , Obesidade/metabolismo , Termogênese/efeitos dos fármacos
9.
Angew Chem Int Ed Engl ; 60(20): 11384-11390, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33605007

RESUMO

Chiral carboxylic acids are important compounds because of their prevalence in pharmaceuticals, natural products and agrochemicals. Asymmetric hydrogenation of α,ß-unsaturated carboxylic acids has been widely recognized as one of the most efficient synthetic approaches to afford such compounds. Although related asymmetric hydrogenation of di- and trisubstituted unsaturated acids with noble metals is well established, asymmetric hydrogenation of challenging tetrasubstituted α,ß-unsaturated carboxylic acids is rarely reported. We demonstrate enantioselective hydrogenation of cyclic and acyclic tetrasubstituted α,ß-unsaturated carboxylic acids via cobalt(II) catalysis. This protocol showed broad substrate scope and gave chiral carboxylic acids in good yields with excellent enantiocontrol (up to 98 % yield and 99 % ee). Combined experimental and computational mechanistic studies support a CoII catalytic cycle involving migratory insertion and σ-bond metathesis processes. DFT calculations reveal that enantioselectivity may originate from the steric effect between the phenyl groups of the ligand and the substrate.

11.
J Am Chem Soc ; 141(51): 20424-20433, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31791120

RESUMO

The development of catalysts based on earth abundant metals in place of noble metals is becoming a central topic of catalysis. We herein report a cobalt/tetraphosphine complex-catalyzed homogeneous hydrogenation of polar unsaturated compounds using an air- and moisture-stable and scalable precatalyst. By activation with potassium hydroxide, this cobalt system shows both high efficiency (up to 24 000 TON and 12 000 h-1 TOF) and excellent chemoselectivities with various aldehydes, ketones, imines, and even N-heteroarenes. The preference for 1,2-reduction over 1,4-reduction makes this method an efficient way to prepare allylic alcohols and amines. Meanwhile, efficient hydrogenation of the challenging N-heteroarenes is also furnished with excellent functional group tolerance. Mechanistic studies and control experiments demonstrated that a CoIH complex functions as a strong hydride donor in the catalytic cycle. Each cobalt intermediate on the catalytic cycle was characterized, and a plausible outer-sphere mechanism was proposed. Noteworthy, external inorganic base plays multiple roles in this reaction and functions in almost every step of the catalytic cycle.

12.
J Org Chem ; 84(22): 14381-14393, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31664828

RESUMO

The structure of a water-soluble hypervalent iodine(V) reagent AIBX is re-examined through its single-crystal X-ray analysis and theoretical calculations including Mayer bond order and localized orbital locator (LOL) and AIBX is believed to be a pseudocyclic iodylarene because of the strong electron-withdrawing nature of the trimethylammonium cation on its phenyl ring, which would decrease the electron density of carboxylic anion and make the ortho-carboxyl oxygen anion incapable to form hypervalent bond with iodine atom. However, the cyclic benziodoxole structure of AIBX could be obtained by adding a Brønsted acid, which was supported by the calculation result including the increase of Mayer bond order and the shortening of the I-O bond length. Moreover, the fact that the system of AIBX and TFA could oxidize various alcohols to their corresponding carbonyl compounds would indicate that AIBX constitutes a cyclic benziodoxole structure under acidic conditions. In addition, an efficient method has been developed for the synthesis of isoxazoline N-oxides via AIBX-induced dehydrogenative cyclization using ß-keto esters as substrates and methyl nitroacetate as a nucleophile.

13.
Mediators Inflamm ; 2019: 4530534, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31565033

RESUMO

Atherosclerosis (AS) is a chronic inflammatory disease, and macrophages play a key role in all phases of AS. Recent studies have shown that miR-221 is a biomarker for AS and stroke; however, the role and mechanism of miR-221 in AS are unclear. Herein, we found that miR-221 and NCoR levels were decreased in ox-LDL-treated THP-1-derived macrophages. In contrast, DNMT3b, IL-6, and TNF-α expression levels were increased under these conditions. Upregulation of miR-221 or NCoR could partially inhibit ox-LDL-induced IL-6 and TNF-α expression. Further studies showed that DNMT3b was a target of miR-221. DNMT3b inhibition also suppressed IL-6 and TNF-α expression and increased NCoR expression in the presence of ox-LDL. Moreover, DNMT3b was involved in ox-LDL-induced DNA methylation in the promoter region of NCoR. These findings suggest that miR-221 suppresses ox-LDL-induced inflammatory responses via suppressing DNMT3b-mediated DNA methylation in the promoter region of NCoR. These results provide a rationale for using intracellular miR-211 as a possible antiatherosclerotic target.


Assuntos
Inflamação/metabolismo , Lipoproteínas LDL/metabolismo , Macrófagos/metabolismo , MicroRNAs/metabolismo , Western Blotting , DNA (Citosina-5-)-Metiltransferases/metabolismo , Células HEK293 , Humanos , Interleucina-6/metabolismo , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase em Tempo Real , Células THP-1 , Fator de Necrose Tumoral alfa/metabolismo , DNA Metiltransferase 3B
14.
Cell Biol Int ; 42(11): 1564-1574, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30136751

RESUMO

Ovarian cancer is one of the most common gyneacologic malignancies, with high morbidity and high mortality. Hsa-miR-122-5p (miR-122) has been reported with tumor-suppressing roles in various cancers. In this study, miR-122 was overexpressed in ovarian cancer cells, and phenotypic experiments demonstrated that miR-122 inhibited migration and invasion in SKOV3 and OVCAR3 cells. MiR-122 also suppressed epithelial mesenchymal transition (EMT), evidenced by expression changes of E-cadherin, vimentin, matrix metalloproteinase (MMP)2, and MMP14. Prolyl-4-hydroxylase subunit alpha-1 (P4HA1) was identified as a target of miR-122, and downregulated by miR-122. MiR-122-induced the elevation of migration, invasion, and EMT were recovered by P4HA1. Additionally, miR-122 restrained the tumor metastasis of SKOV3 cells in peritoneal cavity of nude mice. In summary, we demonstrated that miR-122 inhibited migration, invasion, EMT, and metastasis in peritoneal cavity of ovarian cancer cells by targeting P4HA1 for the first time, which shed lights on the discovery of miR-122 and P4HA1 as possible potential diagnostic markers and therapeutic targets for ovarian cancer.


Assuntos
Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Pró-Colágeno-Prolina Dioxigenase/genética , Animais , Sequência de Bases , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação para Baixo/genética , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias Peritoneais/patologia , Neoplasias Peritoneais/secundário , Fenótipo , Pró-Colágeno-Prolina Dioxigenase/metabolismo
15.
Bioorg Med Chem ; 26(8): 2017-2027, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29545016

RESUMO

To discover more derivatives with better glucose-lowering efficacy compared with berberine, twenty-three novel compounds with 4,7,12,12a-tetrahydro-5H-thieno[3',2':3,4]pyrido[1,2-b]isoquinoline or 5,8,12,12a-tetrahydro-6H-thieno[2',3':4,5]pyrido[2,1-a]isoquinoline cores were designed, synthesized, and biologically evaluated in vitro in continuation of our previous work on indirect activators of adenosine 5'-monophosphate-activated protein kinase (AMPK). Nine compounds effectively stimulated glucose consumption (>2.3-fold at 10 µM) in L6 myotube cells, and two compounds (4d and 4s) exhibited superior inhibitory activity (<57.6% at 5 µM) compared with berberine on gluconeogenesis in rat primary hepatocytes. Additionally, these compounds significantly up-regulated the phosphorylation of AMPK and its substrate, acetyl-CoA carboxylase (ACC) and slightly decreased the mitochondrial membrane potential in L6 myotube cells.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Desenho de Fármacos , Isoquinolinas/química , Proteínas Quinases Ativadas por AMP/química , Animais , Células Cultivadas , Glucose/metabolismo , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Isoquinolinas/síntese química , Isoquinolinas/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
16.
J Nat Prod ; 80(4): 899-908, 2017 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-28345906

RESUMO

LC-MS-guided phytochemical isolation of malonylginsenosides, featuring neutral elimination of CO2 and C3H2O3 by the negative mode collision-induced dissociation, from the flower buds of Panax ginseng led to the isolation of 19 malonyl-substituted triterpenoid saponins. They include 15 new malonylginsenosides, malonylfloralginsenosides-Re1-Re3 (1-3), -Rb1 and -Rb2 (4, 5), -Rd1-Rd6 (6-11), and -Rc1-Rc4 (12-15), and the known m-Rb1, m-Rc, m-Rb2, and m-Rd (16-19). Compound 11 represents the first dimalonyl saponin isolated from the Panax genus, while 2-4, 9, and 10 are five ginsenosides with single malonylation at the C-20 sugar chain. The antidiabetic activities of nine of these malonyl-substituted ginsenosides (1, 3, 4, 8, 13, and 16-19) and five of the corresponding non-malonyl ginsenosides (Re, Rb1, Rb2, Rc, and Rd) were evaluated by L6 myotubes' glucose consumption and AMPKα2ß1γ1 activation. Ginsenoside Rb2, 1, and 18 promoted glucose consumption of differentiated L6 myotubes, while ginsenosides Rb1, Rb2, and Rd and the malonylginsenosides 4, 8, 13, 16, 17, and 19 activated AMPKα2ß1γ1 (EC50: 0.0168-2.8 µM, fold: 1.7-4.7).


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Flores/química , Ginsenosídeos/isolamento & purificação , Ginsenosídeos/farmacologia , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/farmacologia , Panax/química , Saponinas/isolamento & purificação , Saponinas/farmacologia , Animais , Cromatografia Líquida , Diabetes Mellitus/tratamento farmacológico , Medicamentos de Ervas Chinesas/química , Ginsenosídeos/química , Hipoglicemiantes/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Ratos , Saponinas/química
17.
J Lipid Res ; 57(12): 2176-2184, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27729386

RESUMO

Cluster of differentiation 36 (CD36) variants influence fasting lipids and risk of metabolic syndrome, but their impact on postprandial lipids, an independent risk factor for cardiovascular disease, is unclear. We determined the effects of SNPs within a ∼410 kb region encompassing CD36 and its proximal and distal promoters on chylomicron (CM) remnants and LDL particles at fasting and at 3.5 and 6 h following a high-fat meal (Genetics of Lipid Lowering Drugs and Diet Network study, n = 1,117). Five promoter variants associated with CMs, four with delayed TG clearance and five with LDL particle number. To assess mechanisms underlying the associations, we queried expression quantitative trait loci, DNA methylation, and ChIP-seq datasets for adipose and heart tissues that function in postprandial lipid clearance. Several SNPs that associated with higher serum lipids correlated with lower adipose and heart CD36 mRNA and aligned to active motifs for PPARγ, a major CD36 regulator. The SNPs also associated with DNA methylation sites that related to reduced CD36 mRNA and higher serum lipids, but mixed-model analyses indicated that the SNPs and methylation independently influence CD36 mRNA. The findings support contributions of CD36 SNPs that reduce adipose and heart CD36 RNA expression to inter-individual variability of postprandial lipid metabolism and document changes in CD36 DNA methylation that influence both CD36 expression and lipids.


Assuntos
Antígenos CD36/genética , Remanescentes de Quilomícrons/sangue , Lipoproteínas LDL/sangue , Adulto , Ilhas de CpG , Metilação de DNA , Feminino , Expressão Gênica , Frequência do Gene , Estudos de Associação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/metabolismo , Especificidade de Órgãos , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Triglicerídeos/sangue
18.
Chemistry ; 21(37): 13052-7, 2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-26215427

RESUMO

We have developed a method for recyclable hypervalent-iodine-mediated direct dehydrogenative α,ß'- bifunctionalization of ß-ketoesters and ß-diketones under metal-free conditions, which affords a straightforward way to synthesize benzo-fused 2,3-dihydrofurans. This efficient, mild method, which has a wide substrate scope and good functional-group tolerance, was used for the multistep synthesis of the protected aglycone of a naturally occurring phenolic glycoside. A mechanism involving Michael addition to an enone intermediate and subsequent oxidative cyclization is proposed.

19.
Biomolecules ; 14(6)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38927022

RESUMO

Recent studies increasingly suggest that targeting brown/beige adipose tissues to enhance energy expenditure offers a novel therapeutic approach for treating metabolic diseases. Brown/beige adipocytes exhibit elevated expression of uncoupling protein 1 (UCP1), which is a thermogenic protein that efficiently converts energy into heat, particularly in response to cold stimulation. Polyphenols possess potential anti-obesity properties, but their pharmacological effects are limited by their bioavailability and distribution within tissue. This study discovered 18a, a polyphenol compound with a favorable distribution within adipose tissues, which transcriptionally activates UCP1, thereby promoting thermogenesis and enhancing mitochondrial respiration in brown adipocytes. Furthermore, in vivo studies demonstrated that 18a prevents high-fat-diet-induced weight gain and improves insulin sensitivity. Our research provides strong mechanistic evidence that UCP1 is a complex mediator of 18a-induced thermogenesis, which is a critical process in obesity mitigation. Brown adipose thermogenesis is triggered by 18a via the AMPK-PGC-1α pathway. As a result, our research highlights a thermogenic controlled polyphenol compound 18a and clarifies its underlying mechanisms, thus offering a potential strategy for the thermogenic targeting of adipose tissue to reduce the incidence of obesity and its related metabolic problems.


Assuntos
Dieta Hiperlipídica , Obesidade , Polifenóis , Termogênese , Proteína Desacopladora 1 , Proteína Desacopladora 1/metabolismo , Proteína Desacopladora 1/genética , Termogênese/efeitos dos fármacos , Animais , Obesidade/metabolismo , Obesidade/tratamento farmacológico , Polifenóis/farmacologia , Camundongos , Dieta Hiperlipídica/efeitos adversos , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Marrom/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Humanos , Metabolismo Energético/efeitos dos fármacos
20.
Stem Cell Res Ther ; 15(1): 149, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783393

RESUMO

BACKGROUND: Autoimmune uveitis is an inflammatory disease triggered by an aberrant immune response. Mesenchymal stem cell-derived small extracellular vesicles (MSC-sEVs) are emerging as potential therapeutic agents for this condition. CD73, an ectoenzyme present on MSC-sEVs, is involved in mitigating inflammation by converting extracellular adenosine monophosphate into adenosine. We hypothesize that the inhibitory effect of MSC-sEVs on experimental autoimmune uveitis (EAU) could be partially attributed to the surface expression of CD73. METHODS: To investigate novel therapeutic approaches for autoimmune uveitis, we performed lentiviral transduction to overexpress CD73 on the surface of MSC-sEVs, yielding CD73-enriched MSC-sEVs (sEVs-CD73). Mice with interphotoreceptor retinoid-binding protein (IRBP)-induced EAU were grouped randomly and treated with 50 µg MSC-sEVs, vector infected MSC-sEVs, sEVs-CD73 or PBS via single tail vein injection. We evaluated the clinical and histological features of the induced mice and analyzed the proportion and functional capabilities of T helper cells. Furthermore, T-cells were co-cultured with various MSC-sEVs in vitro, and we quantified the resulting inflammatory response to assess the potential therapeutic benefits of sEVs-CD73. RESULTS: Compared to MSC-sEVs, sEVs-CD73 significantly alleviates EAU, leading to reduced inflammation and diminished tissue damage. Treatment with sEVs-CD73 results in a decreased proportion of Th1 cells in the spleen, draining lymph nodes, and eyes, accompanied by an increased proportion of regulatory T-cells (Treg cells). In vitro assays further reveal that sEVs-CD73 inhibits T-cell proliferation, suppresses Th1 cells differentiation, and enhances Treg cells proportion. CONCLUSION: Over-expression of CD73 on MSC-sEVs enhances their immunosuppressive effects in EAU, indicating that sEVs-CD73 has the potential as an efficient immunotherapeutic agent for autoimmune uveitis.


Assuntos
5'-Nucleotidase , Doenças Autoimunes , Vesículas Extracelulares , Células-Tronco Mesenquimais , Uveíte , Animais , Uveíte/patologia , Uveíte/terapia , Uveíte/metabolismo , Uveíte/imunologia , 5'-Nucleotidase/metabolismo , 5'-Nucleotidase/genética , Vesículas Extracelulares/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/imunologia , Camundongos , Doenças Autoimunes/terapia , Doenças Autoimunes/patologia , Doenças Autoimunes/imunologia , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Feminino , Proteínas de Ligação ao Retinol , Humanos
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