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1.
Org Biomol Chem ; 22(20): 4057-4061, 2024 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-38716633

RESUMO

An efficient and practical one-pot synthesis of isoindolines from readily available starting materials was achieved under mild conditions by implementing an isoindole umpolung strategy. A variety of isoindolines were prepared with good to excellent yields. Biological screens of these identified compounds demonstrated that they are potent potentiators of colistin for multi-drug resistant Acinetobacter baumannii.


Assuntos
Acinetobacter baumannii , Antibacterianos , Colistina , Farmacorresistência Bacteriana Múltipla , Testes de Sensibilidade Microbiana , Acinetobacter baumannii/efeitos dos fármacos , Colistina/farmacologia , Colistina/síntese química , Colistina/química , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/farmacologia , Antibacterianos/química , Isoindóis/síntese química , Isoindóis/farmacologia , Isoindóis/química , Estrutura Molecular , Relação Estrutura-Atividade
2.
Comput Biol Chem ; 110: 108088, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38685167

RESUMO

Cichorium glandulosum, a common traditional Chinese medicine used by Uyghur and Mongolian ethnic groups, is recognized for its potential to ameliorate metabolic disorders. However, the specific efficacy and mechanisms of Cichorium glandulosum in treating the comorbidity of hyperuricaemia and hyperlipidaemia remain unexplored. This study aims to explore the pharmacological effects and mechanisms of Cichorium glandulosum on this comorbidity through a combination of animal experiments, network pharmacology, and molecular docking techniques. A rat model of hyperuricaemia combined with hyperlipidaemia was established through a high-fat and high-purine diet, and the effective parts of the aqueous extract of Cichorium glandulosum to reduce uric acid and lipid levels were screened and the components of the parts were analysed by LC-MS/MS. The active components, core targets, and key pathways were analysed using network pharmacology and validated by molecular docking. Animal experimental results indicated that the n-butanol extract of Cichorium glandulosum showed a significant therapeutic effect on this comorbidity. Analysis of the n-butanol extract yielded 35 active ingredients and 138 intersecting targets related to diseases. Key targets identified through compound-target-pathway (C-T-P) and Protein-Protein Interaction (PPI) analyses included RELA, CASP3, PTGS2, TNF, and ESR1. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses revealed 2515 functional items and 164 pathways, respectively. Molecular docking demonstrated that isochlorogenic acid A, baicalin, chicoric acid, and lactucopicrin showed the highest binding affinity to RELA and PTGS2. The n-butanol fraction from the aqueous extract of Cichorium glandulosum was found to reduce uric acid and lipid levels effectively. In summary, Cichorium glandulosum has a therapeutic effect on hyperuricaemia combined with hyperlipidaemia through its multi-component, multi-target, and multi-pathway characteristics.


Assuntos
Hiperlipidemias , Hiperuricemia , Simulação de Acoplamento Molecular , Farmacologia em Rede , Extratos Vegetais , Hiperuricemia/tratamento farmacológico , Hiperuricemia/metabolismo , Animais , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/metabolismo , Ratos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Masculino , Ratos Sprague-Dawley , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa , Modelos Animais de Doenças
3.
Prep Biochem Biotechnol ; : 1-12, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38334942

RESUMO

This study aims to establish a method for purifying total flavonoids in roses using macroporous resin columns, intending to leverage and harness their potential. We screened six macroporous resins to evaluate their capacity for their adsorption and desorption, ultimately identifying X5 macroporous resin as the most effective. To comprehensively understand the adsorption behavior, we analyzed it using various models, such as pseudo-first-order and pseudo-second-order kinetic models, particle diffusion models, and Langmuir, Freundlich, and Temkin isotherm models. Employing both single-factor and uniform design, approaches, the focus of this work was on maximizing the total flavonoid recovery rate. A 3-factor and 10-level uniform design table was utilized for optimizing the optimal process parameters and exploring the antioxidant properties of the purified flavonoids. The optimal process conditions for purifying total flavonoids from roses can be summarized as follows: a sample concentration of 2 mg/mL, pH at 2, 55 mL sample volume, eluent ethanol concentration of 75%, eluent volume of 5 BV, and the elution rate set at 1 mL/min. Following purification, the total flavonoid content peaked at 57.82%, achieving an 84.93% recovery rate, signifying substantial antioxidant potential. Consequently, the method established for purifying TFR using X5 macroporous resin in this study proves to be a dependable and reliable method consistent approach.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 308: 123683, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38006864

RESUMO

Detecting heavy metal copper ions in lubricating oil holds immense significance for assessing mechanical wear and predicting mechanical failure. While perovskite nanocrystals offer high sensitivity in detecting copper ions, traditional lead halide perovskites suffer from lead toxicity defects. Lead-free perovskites, like Cs2NaInCl6, avoid the issue of lead toxicity but display lower luminescence intensity due to the presence of forbidden optical transitions. To address these issues, this study synthesized Cs2NaInCl6 nanocrystals (NCs) co-doped with Sb3+ and Tb3+ ions for copper ions detection in lubricating oil. The introduction of Sb3+ effectively reduced the band gap of the Cs2NaInCl6 host, creating an energy transfer pathway for Tb3+ emission via self-trapped excitations (STEs). Moreover, the doping of Tb3+ ions resulted in the suppression of STEs emission due to electron transfer from STEs to Tb3+. The emission of Tb3+ increased initially and then decreased with the increasing Tb3+ concentration, peaking at 40 %. Finally, Cs2NaInCl6: 2.5 %Sb3+, 40 %Tb3+ NCs were employed as probes for copper ions detection, exhibiting superior sensitivity and selectivity compared to similar probes. The presence of copper ions introduced competition between copper and Tb3+ for electrons from STEs, consequently leading to the quenching of multiple emission intensities associated with STEs and Tb3+. This method shows promising potential in predicting mechanical failure.

5.
Nanomaterials (Basel) ; 13(24)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38132999

RESUMO

Novel and high-security anti-counterfeiting technology has always been the focus of attention and research. This work proposes a nanocomposite combination of upconversion nanoparticles (UCNPs) and perovskite quantum dots (PeQDs) to achieve color-adjustable dual-mode luminescence anti-counterfeiting. Firstly, a series of NaGdF4: Yb/Tm UCNPs with different sizes were synthesized, and their thermal-enhanced upconversion luminescence performances were investigated. The upconversion luminescence (UCL) intensity of the samples increases with rising temperature, and the UCL thermal enhancement factor rises as the particle size decreases. This intriguing thermal enhancement phenomenon can be attributed to the mitigation of surface luminescence quenching. Furthermore, CsPbBr3 PeQDs were well adhered to the surfaces and surroundings of the UCNPs. Leveraging energy transfer and the contrasting temperature responses of UCNPs and PeQDs, this nanocomposite was utilized as a dual-mode thermochromic anti-counterfeiting system. As the temperature increases, the color of the composite changes from green to pink under 980 nm excitation, while it displays green to non-luminescence under 365 nm excitation. This new anti-counterfeiting material, with its high security and convenience, has great potential in anti-counterfeiting applications.

6.
Antimicrob Agents Chemother ; 67(10): e0005123, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37681969

RESUMO

Novel antibacterial agents and strategies are urgently needed to fight against the ongoing global antibiotic resistance problem. While natural products remain the main source in antibiotic discovery, synthetic antibacterials provide an attractive alternative and may evade the ancient antibiotic resistance. Herein, we report a small molecule that re-sensitizes methicillin-resistant Staphylococcus aureus to ß-lactam antibiotics with extremely low potential for resistance development. It belongs to a new class of broad-spectrum antibacterials, trypyricins, which share similar structural characteristics and mechanism of action to the cationic antimicrobial peptides. Mechanistic studies indicated that trypyricins fluidize and disrupt bacterial cytoplasmic membrane. These results suggested that trypyricins represent a promising new class of antibacterials and may be further developed as antibiotic adjuvants to fight against resistant bacteria in the clinic.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Monobactamas , Resistência Microbiana a Medicamentos
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 288: 122181, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36463625

RESUMO

The content of Cu2+ in lubricating oil and lubricant temperature are important indicators predicting mechanical failure. Therefore, developing a nontoxic fluorescence probe is necessary to detect Cu2+ and temperature in lubricating oil. The lead-free inorganic double perovskite nanocrystals (NCs) Cs2AgInCl6 are potential candidates. However, the low fluorescence intensity and the high excitation energy required of Cs2AgInCl6 NCs limit their practical applications. In this study, Bi3+ and Tb3+ were successfully co-doped into Cs2AgInCl6 NCs via the hot-injection method. The doping of Bi3+ produces a broad emission originating from self-trapped excitons and reduces the excitation energy, allowing commercial LEDs as excitation sources. Tb3+ ions doping offers characteristic emission peaks (5D0-7FJ) of Tb3+ ions and improves the fluorescence intensity of Cs2AgInCl6 NCs. Furthermore, the Cs2AgInCl6: Bi3+/Tb3+ NCs have been employed as optical thermometry, which provide a temperature calibration curve with the maximum absolute and relative sensitivities of 2.15% K-1 at 350 K and 2.25% K-1 at 303 K in the temperature range of 303-423 K, respectively. Finally, the nanocrystals have been applied to detect Cu2+ in lubricating oil. The fluorescent probe shows a good detection sensitivity of 8.94 × 10-4 nM-1 and a low detection limit of 14.3 nM in the range of 10-300 nM. This work not merely offers a novel way for improving the luminescence performances of double perovskite NCs Cs2AgInCl6, but broadens their potential for detection of Cu2+ and temperature.

8.
Bioorg Med Chem Lett ; 72: 128878, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35788034

RESUMO

Multidrug-resistant (MDR) Gram-negative bacteria are an urgent and rapidly spreading threat to human health with limited treatment options. Previously, we discovered a novel [1,2,5]oxadiazolo[3,4-b]pyrazine-containing compound (1) that selectively re-sensitized a variety of MDR Gram-negative bacteria to colistin, one of the last-resort antibiotic. Herein, we report the structure-activity relationship studies of compound 1 that led to the discovery of several more potent and/or less toxic resistance-modifying agents (RMAs). Further evaluation of these RMAs showed that they were effective in a wide range of MDR bacteria. These results demonstrated these compounds as a novel class of RMAs and may be further developed as therapeutic agents.


Assuntos
Infecções por Bactérias Gram-Negativas , Polimixinas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana Múltipla , Bactérias Gram-Negativas , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana , Polimixinas/farmacologia , Pirazinas/farmacologia , Pirazinas/uso terapêutico , Relação Estrutura-Atividade
9.
Front Cell Dev Biol ; 10: 956334, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35837331

RESUMO

The rapid development of medical technology and widespread application of immunosuppressive drugs have improved the success rate of organ transplantation significantly. However, the use of immunosuppressive agents increases the frequency of malignancy greatly. With the prospect of "precision medicine" for tumors and development of next-generation sequencing technology, more attention has been paid to the application of high-throughput sequencing technology in clinical oncology research, which is mainly applied to the early diagnosis of tumors and analysis of tumor-related genes. All generations of cancers carry somatic mutations, meanwhile, significant differences were observed in mutational signatures across tumors. Systematic sequencing of cancer genomes from patients after organ transplantation can reveal DNA damage and repair processes in exposed cancer cells and their precursors. In this review, we summarize the application of high-throughput sequencing and organoids in the field of organ transplantation, the mutational patterns of cancer genomes, and propose a new research strategy for understanding the mechanism of cancer following organ transplantation.

10.
ACS Omega ; 7(14): 12442-12446, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35449921

RESUMO

Antibiotic resistance is a growing global health concern. Colistin is one of the last-resort antibiotics that treats multidrug-resistant (MDR) Gram-negative bacterial infection. However, bacteria resistant to colistin have become increasingly prevalent. Using a bacterial whole-cell screen of a fragment-based library, one compound was discovered to resensitize MDR Escherichia coli AR-0493 to colistin with low mammalian toxicity. Interestingly, postscreening validation studies identified a highly related yet distinct compound as the actual substance responsible for the activity. Further studies showed that this novel resistance-modifying agent is not only very potent but also highly selective to potentiate the activity of polymyxin family antibiotics in a wide range of MDR Gram-negative bacteria. Thus, it may be further developed as a combination therapy to prolong the life span of colistin in the clinic.

11.
Anim Biotechnol ; 33(2): 392-400, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32615852

RESUMO

The effect of Vitamin E on the proliferation of ovine Sertoli cells was investigated. Sertoli cells were isolated and treated with various amounts of Vitamin E (0 µM, 400 µM, 800 µM, 1000 µM, 1200 µM, 1400 µM and 1600 µM) for 24 h. We found that at the concentration of 1200 µM, Vitamin E promoted Sertoli cell proliferation very effectively. It also increased the proportion of cells in the G1 phase while reduced that in the S and G2/M phases, suggesting that its effect on Sertoli cell proliferation is achieved by enhancing progression through the cell cycle. In addition, Vitamin E significantly up-regulated the transcript level of the PDPN, BMP6, AMPKα, GSK3ß, Myc, and CDK6 genes and down-regulated that of PPARγ, Cyclin B1 and CDK4 as determined by qRT-PCR. Western blot analysis revealed that the expression of BMP6 and PDPN was also upregulated at the protein level, in accordance with the results of the qRT-PCR. Taken together, Vitamin E promoted Sertoli cell proliferation by affecting the expression of genes that regulate cell division and the cell cycle; this indicates that it can have a positive effect on sheep reproductive performance.


Assuntos
Células de Sertoli , Vitamina E , Animais , Ciclo Celular/genética , Divisão Celular , Proliferação de Células/genética , Masculino , Ovinos/genética
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120275, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34411769

RESUMO

A turn on upconversion fluorescence probe based on the combination of ~32 nm NaYF4: Yb/Tm nanoparticles and MnO2 nanosheets has been established for rapid, sensitive detection of Fe2+ ions levels in aqueous solutions and serum. X-ray diffraction (XRD), transmission electron microscopy (TEM), absorption and emission spectra have been used to characterize the crystal structure, morphology and optical properties of the samples. MnO2 nanosheets on the surface of UCNPs act as a fluorescence quencher, resulting in the quenching of the blue fluorescence (with excitation/emission maximum of 980/476 nm) via fluorescence resonance energy transfer from upconversion nanoparticles to MnO2 nanosheets. With the adding of Fe2+, upconversion fluorescence of the nanocomposites recovers due to the reduction of MnO2 to Mn2+. Because of the low background of the probe offered by upconversion fluorescence, this probe can be used for detecting Fe2+ in aqueous solutions in the range of 0.1-22 µM with detection limit of 0.113 µM. The developed method has also been applied to detect 10 µM Fe2+ ions in serum with recoveries ranging from 97.6 to 105.3% for the five serum samples. Significantly, the probe shows fast response and stable signal, which is beneficial for long-time dynamic sensing. Thus, the proposed strategy holds great potential for disease diagnosis and treatment.


Assuntos
Compostos de Manganês , Nanopartículas , Transferência Ressonante de Energia de Fluorescência , Íons , Óxidos
13.
Br J Nutr ; 128(1): 1-12, 2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34325757

RESUMO

Maternal folic acid (FA) plays an important role in the fetus development, but it is unknown the response of hepatic metabolism in the offspring from different litter sizes to maternal FA supplementation. In the present study, this was done by feeding the ewes with 0, 16 and 32 mg/(kg·DM) FA supplemented diet during pregnancy and analysing the hepatic one-carbon metabolism-related indices and gene expression in the neonatal lambs of different litter sizes (twins, TW; triplets, TR). Regardless of litter sizes, the concentrations of folate, methionine, S-adenosylmethionine and DNA methyltransferase increased significantly, but homocysteine and S-adenosylhomocysteine decreased in the liver of newborn lambs from ewes whose diet was supplemented with FA. In TW, maternal FA status has little effect on hepatic genes expression profile of newborn lambs, and no significant enriched pathway was found. However, DEG involved in cell proliferation such as CCNA2, CCNB2, CCNE2, CDK1 and BUB1 were significantly enriched when the ewes were supplemented with FA in TR groups. In addition, nucleotide synthesis-related genes such as POLD1, POLD2, MCM4 and MCM5 were enriched markedly in DNA replication and pyrimidine metabolism pathways in triplets when a higher FA ingestion [32 mg/(kg·DM)] was implemented in ewes. This finding demonstrated that the hepatic methyl metabolism in TW and TR newborn lambs was regulated by maternal FA status. The hepatic cell proliferation and nucleotide metabolism related genes in TR were more susceptible to maternal dietary FA supplementation during pregnancy.


Assuntos
Dieta , Suplementos Nutricionais , Gravidez , Animais , Ovinos , Feminino , Tamanho da Ninhada de Vivíparos , Dieta/veterinária , Ácido Fólico/metabolismo , Carneiro Doméstico/metabolismo , Nucleotídeos
14.
Acta Pharmacol Sin ; 43(1): 39-49, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33767380

RESUMO

Alzheimer's disease (AD) is associated with high incidence of cardiovascular events but the mechanism remains elusive. Our previous study reveals a tight correlation between cardiac dysfunction and low mitochondrial aldehyde dehydrogenase (ALDH2) activity in elderly AD patients. In the present study we investigated the effect of ALDH2 overexpression on cardiac function in APP/PS1 mouse model of AD. Global ALDH2 transgenic mice were crossed with APP/PS1 mutant mice to generate the ALDH2-APP/PS1 mutant mice. Cognitive function, cardiac contractile, and morphological properties were assessed. We showed that APP/PS1 mice displayed significant cognitive deficit in Morris water maze test, myocardial ultrastructural, geometric (cardiac atrophy, interstitial fibrosis) and functional (reduced fractional shortening and cardiomyocyte contraction) anomalies along with oxidative stress, apoptosis, and inflammation in myocardium. ALDH2 transgene significantly attenuated or mitigated these anomalies. We also noted the markedly elevated levels of lipid peroxidation, the essential lipid peroxidation enzyme acyl-CoA synthetase long-chain family member 4 (ACSL4), the transcriptional regulator for ACLS4 special protein 1 (SP1) and ferroptosis, evidenced by elevated NCOA4, decreased GPx4, and SLC7A11 in myocardium of APP/PS1 mutant mice; these effects were nullified by ALDH2 transgene. In cardiomyocytes isolated from WT mice and in H9C2 myoblasts in vitro, application of Aß (20 µM) decreased cell survival, compromised cardiomyocyte contractile function, and induced lipid peroxidation; ALDH2 transgene or activator Alda-1 rescued Aß-induced deteriorating effects. ALDH2-induced protection against Aß-induced lipid peroxidation was mimicked by the SP1 inhibitor tolfenamic acid (TA) or the ACSL4 inhibitor triacsin C (TC), and mitigated by the lipid peroxidation inducer 5-hydroxyeicosatetraenoic acid (5-HETE) or the ferroptosis inducer erastin. These results demonstrate an essential role for ALDH2 in AD-induced cardiac anomalies through regulation of lipid peroxidation and ferroptosis.


Assuntos
Aldeído-Desidrogenase Mitocondrial/metabolismo , Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Coenzima A Ligases/metabolismo , Modelos Animais de Doenças , Presenilina-1/metabolismo , Doença de Alzheimer/patologia , Animais , Relação Dose-Resposta a Droga , Ferroptose , Camundongos , Camundongos Transgênicos , Estrutura Molecular , Contração Miocárdica , Relação Estrutura-Atividade
15.
Molecules ; 26(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34361674

RESUMO

(1) Background: the current research was conducted to investigate the potential non-antioxidant roles of vitamin E in the protection of hepatocysts from oxidative damage. (2) Methods: primary sheep hepatocytes were cultured and exposed to 200, 400, 600, or 800 µmol/L hydrogen peroxide, while their viability was assessed using a CCK-8 kit. Then, cells were treated with 400 µmol/L hydrogen peroxide following a pretreatment with 50, 100, 200, 400, and 800 µmol/L vitamin E and their intracellular ROS levels were determined by means of the DCF-DA assay. RNA-seq, verified by qRT-PCR, was conducted thereafter: non-treated control (C1); cells treated with 400 µmol/L hydrogen peroxide (C2); and C2 plus a pretreatment with 100 µmol/L vitamin E (T1). (3) Results: the 200-800 µmol/L hydrogen peroxide caused significant cell death, while 50, 100, and 200 µmol/L vitamin E pretreatment significantly improved the survival rate of hepatocytes. ROS content in the cells pretreated with vitamin E was significantly lower than that in the control group and hydrogen-peroxide-treated group, especially in those pretreated with 100 µmol/L vitamin E. The differentially expressed genes (DEGs) concerning cell death involved in apoptosis (RIPK1, TLR7, CASP8, and CASP8AP2), pyroptosis (NLRP3, IL-1ß, and IRAK2), and ferroptosis (TFRC and PTGS2). The abundances of IL-1ß, IRAK2, NLRP3, CASP8, CASP8AP2, RIPK1, and TLR7 were significantly increased in the C1 group and decreased in T1 group, while TFRC and PTGS2 were increased in T1 group. (4) Conclusions: oxidative stress induced by hydrogen peroxide caused cellular damage and death in sheep hepatocytes. Pretreatment with vitamin E effectively reduced intracellular ROS levels and protected the hepatocytes from cell death by regulating gene expression associated with apoptosis (RIPK1, TLR7, CASP8, and CASP8AP2) and pyroptosis (NLRP3, IL-1ß, and IRAK2), but not ferroptosis (TFRC and PTGS2).


Assuntos
Antioxidantes/farmacologia , Ferroptose/genética , Expressão Gênica/efeitos dos fármacos , Hepatócitos/metabolismo , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Piroptose/genética , Vitamina E/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ferroptose/efeitos dos fármacos , Regulação da Expressão Gênica , Hepatócitos/efeitos dos fármacos , Fígado/citologia , Piroptose/efeitos dos fármacos , RNA-Seq/métodos , Espécies Reativas de Oxigênio/metabolismo , Ovinos , Transdução de Sinais/efeitos dos fármacos
16.
Micromachines (Basel) ; 12(6)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207022

RESUMO

It is urgent that a convenient and sensitive technique of detecting Hg2+ be developed because of its toxicity. Conventional fluorescence analysis works with a single fluorescence probe, and it often suffers from signal fluctuations which are influenced by external factors. In this research, a novel dual-emission probe assembled through utilizing CdTe quantum dots (QDs) and rhodamine B was designed to detect Hg2+ visually. Only the emission of CdTe QDs was quenched after adding Hg2+ in the dual-emission probe, which caused an intensity ratio change of the two different emission wavelengths and hence facilitated the visual detection of Hg2+. Compared to single emission QDs-based probe, a better linear relationship was shown between the variation of fluorescence intensity and the concentration of Hg2+, and the limit of detection (LOD) was found to be11.4 nM in the range of 0-2.6 µM. Interestingly, the intensity of the probe containing Hg2+ could be recovered in presence of glutathione (GSH) due to the stronger binding affinity of Hg2+ towards GSH than that towards CdTe QDs. Based on this phenomenon, an IMPLICATION logic gate using Hg2+/GSH as inputs and the fluorescence signal of QDs as an output was constructed.

17.
Front Pharmacol ; 12: 683613, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33995112

RESUMO

The development of liver fibrosis is closely related to the gut microbiota, and the "gut-liver axis" is the most important connection between the two. ethyl acetate extract of Cichorium pumilum Jacq (CGEA) is an herbal extract consisting mainly of sesquiterpenoids. The anti-inflammatory and hepatoprotective effects of CGEA have been reported, but the anti-fibrotic effects of CGEA via intestinal microbes and the "gut-liver axis" cycle have rarely been reported. In this study, we observed that CGEA not only directly attenuated inflammatory factor levels in inflamed mice, but also attenuated liver inflammation as well as liver fibrosis degeneration in rats with liver fibrosis caused by colitis. We observed in vitro that CGEA significantly promoted the growth of Bifidobacterium adolescentis. Similarly, fecal 16S rDNA sequencing of liver fibrosis rats showed that CGEA intervention significantly altered the composition of the intestinal microbiota of liver fibrosis rats. CGEA increased the abundance of intestinal microbiota, specifically, CGEA increased the ratio of Firmicutes to Bacteroidetes, CGEA could significantly increase the levels of Ruminococcus. In addition, CGEA intervention significantly protected intestinal mucosal tissues and improved intestinal barrier function in rats. Lactucin is the main sesquiterpenoid in CGEA, and HPLC results showed its content in CGEA was up to 6%. Lactucin has been reported to have significant anti-inflammatory activity, and in this study, we found that Lactucin decreased p38 kinases (p38), phosphorylation of the extracellular signal-regulated kinase (ERK) and protein kinase B (AKT) protein phosphorylation in lipopolysaccharide (LPS)-activated RAW264.7 cells, thereby reducing mRNA expression and protein expression of pro-inflammatory factors inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and inhibiting the release of inflammatory factors interleukin (IL)-6 and nitric oxide (NO), exerting anti-inflammatory effects. In summary, the prevention of liver fibrosis caused by intestinal inflammation by CGEA may be achieved by regulating the intestinal microbiota and restoring the intestinal barrier thereby improving the "gut-liver axis" circulation, reducing liver inflammation, and ultimately alleviating liver fibrosis. Notably, the direct anti-inflammatory effect of CGEA may be due to its content of Lactucin, which can exert anti-inflammatory effects by inhibiting the phosphorylation of Mitogen-activated protein kinase (MAPK) and Akt signaling pathways.

18.
Biol Reprod ; 104(6): 1322-1336, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-33709108

RESUMO

Leydig cells play a critical role in male reproductive physiology, and their dysfunction is usually associated with male infertility. Melatonin has an important protective and regulatory role in these cells. However, the lack of suitable animal models impedes us from addressing the impact of endogenous melatonin on these cells. In the current study, by using arylalkylamine N-acetyltransferase (AANAT) overexpression transgenic sheep and AANAT knockout mice, we confirmed the regulatory effects of endogenously occurring melatonin on Leydig cells as well as its beneficial effects on male reproductive performance. The results showed that the endogenously elevated melatonin level was correlated with decreased Leydig cell apoptosis, increased testosterone production, and improved quality of sperm in melatonin-enriched transgenic mammals. Signal transduction analysis indicated that melatonin targeted the mitochondrial apoptotic Bax/Bcl2 pathway and thus suppressed Leydig cell apoptosis. In addition, melatonin upregulated the expression of testosterone synthesis-related genes of Steroidogenic Acute Regulatory Protein (StAR), Steroidogenic factor 1 (SF1), and Transcription factor GATA-4 (Gata4) in Leydig cells. This action was primarily mediated by the melatonin nuclear receptor RAR-related orphan receptor alpha (RORα) since blockade of this receptor suppressed the effect of melatonin on testosterone synthesis. All of these actions of melatonin cause Leydig cells to generate more testosterone, which is necessary for spermatogenesis in mammals. In contrast, AANAT knockout animals have dysfunctional Leydig cells and reduced reproductive performance.


Assuntos
Antioxidantes/farmacologia , Células Intersticiais do Testículo/metabolismo , Melatonina/farmacologia , Reprodução , Carneiro Doméstico/fisiologia , Testosterona/biossíntese , Animais , Células Intersticiais do Testículo/efeitos dos fármacos , Masculino , Camundongos , Camundongos Knockout
19.
Gene ; 773: 145364, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33359122

RESUMO

Vitamin E is generally believed to promote the production of ovine sperm mainly through its antioxidant effect. Our previous studies have shown that some non-antioxidant genes may also be key in mediating this process. The objective of this study was to identify key candidate proteins that were differentially expressed in response to a treatment with Vitamin E. Prepubertal ovine testicular cells were isolated and divided into two groups. They were either treated with 800 µM Vitamin E (based on our previous results) or used as a non-treated control. After 24 h, all the cells were harvested for proteomic analysis. We found 115 differentially expressed proteins, 4 of which were up-regulated and 111 were down-regulated. A GO term enrichment analysis identified 127 Biological Process, 63 Cell Component and 26 Molecular Function terms that were enriched. Within those terms, 13, 11 and 26 terms were significantly enriched, respectively. Terms related to membrane and enzyme activity including the inner acrosomal membrane, signal peptidase complex, cysteine-type endopeptidase activity, etc., were also markedly enriched, while none of the KEGG pathways were enriched. We found that many of the differentially expressed proteins, such as CD46 (membrane cofactor protein), FLNA (Filamin A), DYSF (Dysferlin), IFT20 (Intraflagellar transport 20), SPCS1 (Signal peptidase complex subunit 1) and SPCS3 (Signal peptidase complex subunit 3) were related to the acrosomal and plasma membranes. A parallel reaction monitoring (PRM) analysis verified that Vitamin E improved spermatogenesis by regulating the expression of FLNA, SPCS3, YBX3 and RARS, proteins that are associated with the plasma membranes and protamine biosynthesis of the spermatozoa.


Assuntos
Protaminas/genética , Ovinos/crescimento & desenvolvimento , Espermatogênese/genética , Vitamina E/genética , Acrossomo/metabolismo , Animais , Membrana Celular , Regulação da Expressão Gênica no Desenvolvimento/genética , Masculino , Proteômica , Ovinos/genética , Espermatozoides/metabolismo , Testículo/crescimento & desenvolvimento , Testículo/metabolismo , Vitamina E/metabolismo
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 230: 118047, 2020 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-31954362

RESUMO

The development of upconversion nanoparticles based logic systems, especially integrated logic systems is still a challenge until now. In this work, an upconversion nanocomposite system is developed and studied for the sensing abilities toward hydrion, hydroxyl ions, metal ions and anions (S2-, I-) by taking the advantages of turn-on and turn-off upconversion fluorescence switching response. Triggering by different kinds of ions, the upconversion system can act as a fluorescence switch due to the specific recognition abilities of Rhodamine 6G functionalized PEI for specific ions and the energy transfer process from upconversion nanoparticles to recognition molecules. Based on these results, multiple molecular logic gates, including single-input logic operation (YES, NOT), double-inputs logic operation (OR, AND, NOR, INHIBIT) and multiple-input integrative logic operation (INHIBIT+OR) are developed by employing hydrion, hydroxyl ions, metal ions and anions as inputs and the changes in the upconversion fluorescence intensity as output. The multiple logic operations are of great significance for the applications in biomedicine and molecular calculation.

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