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1.
ACS Nano ; 18(23): 15154-15166, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38808726

RESUMO

Platinum ditelluride (1T-PtTe2) is a two-dimensional (2D) topological semimetal with a distinctive band structure and flexibility of van der Waals integration as a promising candidate for future electronics and spintronics. Although the synthesis of large-scale, uniform, and highly crystalline films of 2D semimetals system is a prerequisite for device application, the synthetic methods meeting these criteria are still lacking. Here, we introduce an approach to synthesize highly oriented 2D topological semimetal PtTe2 using a thermally assisted conversion called tellurization, which is a cost-efficient method compared to the other epitaxial deposition methods. We demonstrate that achieving highly crystalline 1T-PtTe2 using tellurization is not dependent on epitaxy but rather relies on two critical factors: (i) the crystallinity of the predeposited platinum (Pt) film and (ii) the surface coverage ratio of the Pt film considering lateral lattice expansion during transformation. By optimizing the surface coverage ratio of the epitaxial Pt film, we successfully obtained 2 in. wafer-scale uniformity without in-plane misalignment between antiparallelly oriented domains. The electronic band structure of 2D topological PtTe2 is clearly resolved in momentum space, and we observed an interesting 6-fold gapped Dirac cone at the Fermi surface. Furthermore, ultrahigh electrical conductivity down to ∼3.8 nm, which is consistent with that of single crystal PtTe2, was observed, proving its ultralow defect density.

2.
Adv Mater ; 36(21): e2312013, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38270245

RESUMO

The recent discovery of room-temperature ferromagnetism in 2D van der Waals (vdW) materials, such as Fe3GaTe2 (FGaT), has garnered significant interest in offering a robust platform for 2D spintronic applications. Various fundamental operations essential for the realization of 2D spintronics devices are experimentally confirmed using these materials at room temperature, such as current-induced magnetization switching or tunneling magnetoresistance. Nevertheless, the potential applications of magnetic skyrmions in FGaT systems at room temperature remain unexplored. In this work, the current-induced generation of magnetic skyrmions in FGaT flakes employing high-resolution magnetic transmission soft X-ray microscopy is introduced, supported by a feasible mechanism based on thermal effects. Furthermore, direct observation of the current-induced magnetic skyrmion motion at room temperature in FGaT flakes is presented with ultra-low threshold current density. This work highlights the potential of FGaT as a foundation for room-temperature-operating 2D skyrmion device applications.

3.
Biol Trace Elem Res ; 201(1): 368-376, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35080709

RESUMO

The aim of this study was to investigate the role of selenoproteins in Macranthoidin B (MB) with regard to the inhibition of hepa1-6 cell proliferation. The CCK8 method was used to detect the inhibition rate in hepa1-6 cell of proliferation. The production of ROS, MDA, GSH levels, and GSH-Px and SOD activities was detected according to corresponding reagent kits. We determined the mRNA expressions of 25 selenoproteins in hepa1-6 cells via real-time quantitative PCR (qRT-PCR); moreover, the heat map and principal component analysis were used for further bioinformatics analysis. The results revealed that with an increasing concentration of MB, the inhibitory effect on hepa1-6 cell proliferation intensified. Compared with the control group, the treatment group showed significantly increased ROS levels, elevated MDA contents, and decreased GSH level, GSH-Px activity, and SOD activity. Increasing MB concentration treatment induced remarkable degradation of Txnrd1, Txnrd2, Txnrd3, Gpx1, Gpx2, Gpx3, Gpx6, Dio1, Dio2, Selt, Selp, Selh, Selk, Selw, Seln, and Dio3. Principal component analysis revealed that Txnrd 3, Selk, Selo, Selw, Selt, Dio2, Txnrd1, Dio3, Gpx6, and Dio1 were highly correlated with MB. In conclusion, MB dose dependently inhibited hepa1-6 cell proliferation and induced oxidative stress. Based on bioinformatics analysis, with MB treatment, Txnrd 3, Selk, Selo, Selw, Selt, Dio2, Txnrd1, Dio3, Gpx6, and Dio1 exhibited critical role in the inhibition of hepa1-6 cells proliferation. The functions of these selenoproteins were associated with oxidative stress.


Assuntos
Selênio , Camundongos , Animais , Espécies Reativas de Oxigênio , Selênio/farmacologia , Camundongos Endogâmicos , Selenoproteínas/metabolismo , Estresse Oxidativo , Proliferação de Células , Superóxido Dismutase/metabolismo
4.
Front Pharmacol ; 13: 895724, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935824

RESUMO

JinQi Jiangtang tablet (JQJTT) is a Chinese patent medicine that has been shown to be beneficial for patients with diabetes both preclinically and clinically; however, the molecular mechanism underlying the effects of JQJTT remains unclear. In this study, surface plasmon resonance fishing was employed to identify JQJTT constituent molecules that can specifically bind to fibroblast growth factor receptor 1 (FGFR1), leading to the retrieval of palmatine (PAL), a key active ingredient of JQJTT. In vivo and in vitro experiments demonstrated that PAL can significantly stimulate FGFR1 phosphorylation and upregulate glucose transporter type 1 (GLUT-1) expression, thereby facilitating glucose uptake in insulin resistance (IR) HepG2 cells as well as alleviating hyperglycemia in diabetic mice. Our results revealed that PAL functions as an FGFR1 activator and that the hypoglycemic effect of JQJTT is partially dependent on the PAL-induced activation of the FGFR1 pathway. In addition, this study contributed to the understanding the pharmacodynamic basis and mechanism of action of JQJTT and provided a novel concept for future research on PAL.

5.
Front Immunol ; 13: 857069, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35419003

RESUMO

Schisandrin B (Sch B) is well-known for its antitumor effect; however, its underlying mechanism remains confusing. Our study aimed to investigate the role of selenoproteins in Sch B-induced autophagy and Th1/Th2 imbalance in Hepa1-6 cells. Hepa1-6 cells were chosen to explore the antitumor mechanism and were treated with 0, 25, 50, and 100 µM of Sch B for 24 h, respectively. We detected the inhibition rate of proliferation, transmission electron microscopy (TEM), monodansylcadaverine (MDC) staining, reactive oxygen species (ROS) level and oxidative stress-related indicators, autophagy-related genes, related Th1/Th2 cytokines, and selenoprotein mRNA expression. Moreover, the heat map, principal component analysis (PCA), and correlation analysis were used for further bioinformatics analysis. The results revealed that Sch B exhibited well-inhibited effects on Hepa1-6 cells. Subsequently, under Sch B treatment, typical autophagy characteristics were increasingly apparent, and the level of punctate MDC staining enhanced and regulated the autophagy-related genes. Overall, Sch B induced autophagy in Hepa1-6 cells. In addition, Sch B-promoted ROS accumulation eventually triggered autophagy initiation. Results of Th1 and Th2 cytokine mRNA expression indicated that Th1/Th2 immune imbalance was observed by Sch B treatment in Hepa1-6 cells. Intriguingly, Sch B downregulated the majority of selenoprotein expression. Also, the heat map results observed significant variation of autophagy-related genes, related Th1/Th2 cytokines, and selenoprotein expression in response to Sch B treatment. PCA outcome suggested the key role of Txnrd1, Txnrd3, Selp, GPX2, Dio3, and Selr with its potential interactions in ROS-mediated autophagy and Th1/Th2 imbalance of Hepa1-6 cells. In conclusion, Sch B induced ROS-mediated autophagy and Th1/Th2 imbalance in Hepa1-6 cells. More importantly, the majority of selenoproteins were intimately involved in the process of autophagy and Th1/Th2 imbalance, Txnrd3, Selp, GPX2, Dio3, and Selr had considerable impacts on the process.


Assuntos
Autofagia , Selenoproteínas , Animais , Ciclo-Octanos , Citocinas/metabolismo , Lignanas , Camundongos , Compostos Policíclicos , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Células Th1 , Células Th2
6.
Food Sci Biotechnol ; 30(13): 1709-1719, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34925945

RESUMO

Blueberry residue is usually discarded as waste, but has a high anthocyanins content. The extraction method of anthocyanins from blueberry residue with ultrasonic assisted dual-aqueous phase system was optimized. In terms of the principle of central group and design (CCD) experimental design, three-factor and five-level response surface analysis was adopted to optimize the extraction conditions with the extraction rate of anthocyanins. The optimum extraction rate of anthocyanin was 12.372 ± 0.078 mg/g. Anthocyanin extract could protect the pBR322 DNA oxidative damage induced by Fenton reagent, increase the superoxide dismutase(SOD) and glutathione peroxidase (GSH-Px) enzyme activities, and decrease the H2O2-induced cell apoptosis of human normal liver cell (LO2 cell). The study indicates that the extraction rate of anthocyanin was increased by optimized ultrasonic assisted dual-aqueous phase system. The anthocyanin extract could protect DNA and LO2 cell from oxidative damage.

7.
J Med Food ; 24(2): 116-123, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33523769

RESUMO

This study focused on the antibacterial effects of the endophytic fungi producing naringenin from Dalbergia odorifera T. Chen against Staphylococcus aureus. The antibacterial activity was measured by the inhibition diameters, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). The time-killing curve was also used to evaluate its antibacterial efficacy. The results of antibacterial activity determinations showed that endophytic fungi secondary metabolites can inhibit the growth of five pathogenic bacteria (S. aureus, Escherichia coli, Salmonella enteritidis, Pseudomonas aeruginosa, and Bacillus subtilis) and the most sensitive strain was S. aureus that had the MIC and MBC values of 0.13 and 0.50 mg/mL, respectively. The membrane permeability study was measured by a DNA leakage assay and electrical conductivity assay. Furthermore, the whole-cell protein lysates and DNA fragmentation assay was evaluated. The morphology of S. aureus treated with the endophytic fungi products was observed by scanning electron microscopy (SEM). The probable antibacterial mechanism of endophytic fungi secondary metabolites was the increased membrane permeability that leads to leaks of nucleic acids and proteins. SEM results further confirmed that the extracts can interfere with the integrity of S. aureus cell membrane and further inhibit the growth of bacteria, resulting in the death of bacteria. This study provides a new perspective for the antibacterial functions of endophytic fungi secondary metabolites for biomedical applications.


Assuntos
Proteínas de Bactérias , Membrana Celular , DNA Bacteriano , Dalbergia , Flavanonas , Fungos , Staphylococcus aureus , Antibacterianos/farmacologia , Proteínas de Bactérias/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , DNA Bacteriano/efeitos dos fármacos , Dalbergia/microbiologia , Flavanonas/farmacologia , Fungos/química , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos
8.
Bioengineered ; 12(1): 382-391, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33472492

RESUMO

The trypsin-assisted extraction of polysaccharides from Allium cepa L. was optimized using the response surface methodology (RSM). The optimum extraction conditions were extraction temperature, extraction time, extraction pH, and enzyme amount of 37.16°C, 180 min, 8.57, and 5.16%, respectively. Under the optimized conditions, the yield of A. cepa L. polysaccharides (ACP) reached 9.69%, which was comparable with the predicted yield (9.73%). Mid- and high-dose ACP significantly inhibited the tumor growth (43.93%) and the tumor inhibition percentage (38.05%), which were more than 30%. The ACP could extend the survival time of H22 ascites tumor-bearing mice. Furthermore, the ACP could reduce the thymus and the spleen atrophy and significantly promoted the Con A-induced proliferation of splenocytes and elevated the serum IFN-γ and IL-2 levels. Therefore, the ACP could inhibit the tumor growth in tumor-bearing mice and regulated the immune function of mice. Practical ApplicationsThe trypsin-assisted extraction has high efficiency, is carried out through the polysaccharide extraction and the deproteinization at the same time, and is more convenient and fast than traditional methods. No detailed study on the optimization of the trypsin extraction of onion polysaccharides is available. Thus, this experiment aims to use the BBD (4 factors and 3 levels) to optimize the roles of extraction temperature, extraction time, extraction pH, and amount of enzyme on the yield of polysaccharides obtained from the fruit of A. cepa L. In addition, when looking for high-quality biological functional principles for the pharmaceutical industry, the antitumor activity of ACP was evaluated. A. cepa L. is one of the most widely cultivated and consumed crops worldwide. Polysaccharides are the main active ingredient, and studies have shown that a high intake of Allium vegetables is associated with reduced risk of cancers.


Assuntos
Antineoplásicos Fitogênicos , Cebolas/química , Compostos Fitoquímicos , Polissacarídeos , Tripsina/metabolismo , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células , Citocinas/metabolismo , Feminino , Imunomodulação , Masculino , Camundongos , Neoplasias Experimentais , Cebolas/metabolismo , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Projetos de Pesquisa
9.
Nat Prod Res ; 35(24): 5710-5719, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32998585

RESUMO

Strain SZW01 was isolated from sea sediment collected from Shenzhen in Guangdong province, China, and was later identified as Aspergillus fumigatus by16S rDNA sequence analysis. Various chromatographic processes led to the isolation and purification of three compounds from the fermentation culture of SZW01, including a new compound, 2,6'-dihydroxy-2,4'dimethoxy-8'-methyl-6-methoxy-acyl-ethyl-diphenylmethanone (1), and two known compounds: fumigaclavine C (2) and alternarosin A (3), as characterised by UV, IR, 1 D, 2 D-NMR and MS data. The antioxidant and α-glucosidase inhibitory activities of these compounds were evaluated. The result illustrated that compound 1 exhibited a moderate antioxidant activity and stronger α-glucosidase inhibitory activity than acarbose.


Assuntos
Aspergillus fumigatus , Inibidores de Glicosídeo Hidrolases , Acarbose , Antioxidantes/farmacologia , Aspergillus fumigatus/química , Benzofenonas/farmacologia , China , Sedimentos Geológicos/microbiologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Água do Mar/microbiologia , alfa-Glucosidases
10.
Nat Prod Res ; 35(15): 2489-2497, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31674853

RESUMO

Butyrolactone I, one of the major secondary metabolites of fungus Aspergillus terreus, is a selective cdc2 kinase inhibitor. In the present study, the metabolism of butyrolactone I in male Wistar rats was investigated by characterising metabolites excreted into faeces. Following an oral dose of 40 mg/kg butyrolactone I, two phase I metabolites were isolated from the faeces of rat. The new structure was identified on the spectroscopic data analysis. The new compound V1 and known compound V2 were tested for their cytotoxicity, antimicrobial and antioxidant activity. V1 and V2 showed significant free radical scavenging ability. V2 also showed strong inhibitory activity against Staphylococcus aureus.


Assuntos
4-Butirolactona , Aspergillus/química , Benzofenonas , 4-Butirolactona/análogos & derivados , 4-Butirolactona/farmacologia , Animais , Antibacterianos/farmacologia , Benzofenonas/farmacologia , Fezes , Sequestradores de Radicais Livres/farmacologia , Masculino , Ratos , Ratos Wistar , Staphylococcus aureus/efeitos dos fármacos
11.
Artigo em Inglês | MEDLINE | ID: mdl-33354225

RESUMO

We successfully extracted isoliquiritigenin from Glycyrrhiza uralensis via fermentation with Aspergillus niger and ultrasonic-assisted extraction. In brief, we used A. niger fermentation to culture G. uralensis powder, and we optimized some key parameters such as reaction conditions of pH, inoculation concentration of A. niger, fermentation time, and solid-liquid ratio. Based on a single-factor experiment, we utilized the response surface methodology (RSM) approach to optimize this extraction procedure. Using the RSM approach, optimized conditions of pH = 3.694, the solid-liquid ratio = 1 : 2.155, and the inoculation concentration of A. niger = 1466745 were selected. Optimized conditions resulted in an extraction efficiency of 1.525 mg/g. These results showed that the extraction of isoliquiritigenin was most affected by pH and then the time of fermentation and the solid-liquid ratio. Overall, the developed extraction technique yielded 5 times the amount of isoliquiritigenin when compared to traditional methods.

12.
Biomed Res Int ; 2020: 7102046, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33062693

RESUMO

We successfully extracted isoliquiritigenin from Glycyrrhiza uralensis through the utilization of an ionic liquid-based ultrasonic-assisted extraction (ILUAE) approach. Briefly, we utilized the solution of 1-butyl-3-methylimidazolium bromide ([BMIM]Br) as solvent and optimized key ILUAE parameters such as solid-liquid ratios, concentrations of ionic liquids, and the times of ultrasonication. Based on a single-factor experiment, we utilized the response surface method (RSM) approach to optimize the extraction procedure. The approach revealed that the optimal energy consumption time was 120 min, with the ultrasonic extraction temperature of 60°C. Using these optimized parameters together with the solid-liquid ratio (dried G. uralensis powder: [BMIM]Br of 0.3 mol/L) of 1 : 16.163 and the [BMIM]Br of 0.3 mol/L, we achieved a 0.665 mg/g extraction yield. Overall, these findings thus indicate that we were able to effectively use ILUAE as an efficient approach to reliably extract isoliquiritigenin in a reproducible and environmentally friendly manner.


Assuntos
Chalconas/isolamento & purificação , Glycyrrhiza uralensis/química , Líquidos Iônicos/química , Sonicação/métodos , Imidazóis/química , Preparações de Plantas/química
13.
Biochim Biophys Acta Mol Basis Dis ; 1866(12): 165920, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800946

RESUMO

Neutrophils are key inflammatory cells in the immunopathogenesis of asthma. Neutrophil migration can be initiated through activation of the CXCR1 and CXCR2 receptors by CXC chemokines, such as IL-8. Although transcription factor KLF2 has been found to maintain T cell migration patterns through repression of several chemokine receptors, whether KLF2 can regulate neutrophil migration via modulation of CXCR1 and CXCR2 is unknown. Here, we aimed to explore the functions of KLF2, CXCR1 and CXCR2 in neutrophil migration in asthma and to establish a regulatory role of KLF2 for CXCR1/2. We demonstrate that with asthma aggravation, the percentages and migration rates of peripheral blood neutrophils gradually increased in asthmatic patients and the guinea pig asthma model. Correspondingly, both the KLF2 mRNA and protein levels in neutrophils were gradually reduced. While CXCR1 and CXCR2 expression was negatively correlated with KLF2. In vitro knockdown of KLF2 dramatically increased the migration of HL-60-drived neutrophil-like cells, which was accompanied by an increase in the CXCR1 and CXCR2 mRNA and protein expression levels. Taken together, our results indicate that decreased KLF2 aggravates asthma progression by promoting neutrophil migration, which is associated with the transcriptional upregulation of CXCR1 and CXCR2. The KLF2 and/or CXCR1/2 expression levels may represent an indicator of asthma severity.


Assuntos
Asma/metabolismo , Movimento Celular , Fatores de Transcrição Kruppel-Like/metabolismo , Neutrófilos/citologia , Neutrófilos/metabolismo , Receptores de Interleucina-8A/metabolismo , Receptores de Interleucina-8B/metabolismo , Idoso , Animais , Feminino , Cobaias , Humanos , Masculino , Pessoa de Meia-Idade
14.
Arch Pharm Res ; 43(8): 788-797, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32779151

RESUMO

LXRα agonists have attracted significant attention due to their potential biological activities on promoting cholesterol efflux. This study was designed to investigate whether setosphapyrone C and D have potential lipid-lowering capacity and the underlying mechanisms in vitro. Our data showed that setosphapyrone C and D had weak cytotoxicity compared to the liver X receptor α (LXRα) agonist T0901317. In RAW 264.7 macrophages, setosphapyrone C and D significantly enhanced [3H]-cholesterol efflux by ~ 21.3% and 32.4%, respectively; furthermore, setosphapyrone C and D enhanced the protein levels of ATP-binding cassette transporter (ABC) A1 and LXRα by 58% and 69%, and 60% and 70% (8 µM), respectively; however, they had no effect on the protein levels of ABCG1 and scavenger receptor B type 1; additionally, they had minor effect on the mRNA expression of lipogenic genes. Of note, setosphapyrone C and D significantly enhanced LXRα/ABCA1pathway in mice primary macrophages. In BRL cells, setosphapyrone C and D significantly improved the protein levels of ABCA1 and ABCG1; setosphapyrone D significantly enhanced the protein expression of low-density lipoprotein. Collectively, setosphapyrone C and D with weak cytotoxicity exhibited effective lipid-lowering effect via enhancing LXRα/ABC pathways. Setosphapyrones possess potential application for the treatment of hyperlipidemic diseases.


Assuntos
Colesterol/metabolismo , Hipolipemiantes/farmacologia , Receptores X do Fígado/agonistas , Macrófagos/efeitos dos fármacos , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Hidrocarbonetos Fluorados/farmacologia , Receptores X do Fígado/metabolismo , Macrófagos/metabolismo , Camundongos , Células RAW 264.7 , Sulfonamidas/farmacologia
15.
Exp Ther Med ; 20(1): 630-636, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32537020

RESUMO

Undaria pinnatifida (U. pinnatifida) polysaccharides (UPPS) are considered to be the major bioactive components of U. pinnatifida. The aim of the present study was to investigate the separation, sulfated modification, characterization and monosaccharide composition of UPPS. The optimal processing conditions were as follows: Distilled water-to-solid ratio, 50 ml/g; extraction time, 300 min; and extraction temperature, 90˚C. The major polysaccharide fraction of U. pinnatifida (UPPS-B1) was purified via DEAE-52 and Sephadex G-200 column chromatography. The chlorosulfonic acid-pyridine method was applied for sulfation modification. UPPS-B1 and sulfated (S)-UPPS-B1 were characterized via chemical analysis, ultraviolet-visible and Fourier-transformed infrared spectroscopy, gas chromatography and high-performance liquid chromatography. The total sugar content of UPPS-B1 and S-UPPS-B1 was 79.78 and 77.28%, respectively. The sulfate radical content of UPPS-B1 and S-UPPS-B1 was 8.53 and 29.12%, whilst the content of uronic acid was 9.29 and 7.98%, respectively. The average molecular weight of UPPS-B1 and S-UPPS-B1 was determined to be 37 and 110 kD, respectively. UPPS-B1 was considered to be a heteropolysaccharide composed of xylose, mannose, glucose and galactose at a ratio of 7.9:8.7:12.0:9.8. In addition, S-UPPS-B1 was a heteropolysaccharide composed of xylose, mannose, glucose and galactose at a ratio of 1.0:9.7:6.4:1.6. The results of the tumor growth inhibition experiment demonstrated that UPPS-B1 exhibited anti-tumor activity in vivo, which was improved following sulfation to yield S-UPPS-B1.

16.
Colloids Surf B Biointerfaces ; 193: 111069, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32371286

RESUMO

Cajaninstilbene acid (CSA) exerts wide pharmacological activities, such as anti-inflammation, hypoglycaemic activity, analgesic effect and cognition improvement. However, it underwent severe phase II metabolism mediated by UDP-glucuronosyltransferase (UGT) in the gastrointestinal (GI) tract after oral administration, affecting its oral bioavailability. In the present study, we utilize UGT inhibitory excipient containing self-microemulsion (SME) delivery system to reduce the production of glucuronide metabolites and increase its oral bioavailability. The present results showed that although similar properties in physiochemical, cytotoxicity, cellular uptake, absorption and transport across rat everted gut sacs between SME-1 (inhibitory excipient containing SME) and SME-2 (control SME, without inhibitory excipient), an improved absolute bioavailability of 57.3 % was conferred by SME-1, significantly higher than the value of 35.4 % by SME-2 and 34.0 % by free CSA. Noticeably, the significantly lower AUC value of CSA glucuronide was determined in rats treated with SME-1 than those either treated with SME-2 or free CSA. Thus, the ability of SME-1 to enhance oral bioavailability of CSA is mainly attributed to the inhibition of phase II metabolism in the GI tract.


Assuntos
Inibidores Enzimáticos/farmacologia , Glucuronosiltransferase/antagonistas & inibidores , Salicilatos/farmacologia , Estilbenos/farmacologia , Administração Oral , Animais , Disponibilidade Biológica , Emulsões/administração & dosagem , Emulsões/farmacologia , Inibidores Enzimáticos/administração & dosagem , Glucuronosiltransferase/metabolismo , Humanos , Masculino , Ratos , Ratos Wistar , Salicilatos/administração & dosagem , Estilbenos/administração & dosagem , Células Tumorais Cultivadas
17.
Biomed Chromatogr ; 34(8): e4845, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32267542

RESUMO

An ultra-high performance liquid chromatography tandem mass spectrometry method was developed for determination of homocysteine (HCY) in human plasma. The HCY was derivatized with 2-chloro-1-methylquinolinium tetrafluoroborate and isolated using solid-phase extraction. Derivatization, isolation and detection procedures were optimized. Satisfactory linearity was obtained with determination coefficients (r2 ) >0.999. The intra- and inter-day precisions were in the interval of 1.2-5.1% and accuracy was within ±7%. Mean recoveries were close to 100%. The limit of detection and the limit of quantification were 0.46 and 1.38 µmol/L, respectively. The method was then applied to investigate the relationship between plasma HCY and whole blood 5-methyltetrahydrofolate levels in healthy volunteers. The results revealed that the plasma level of HCY was significantly negatively correlated to whole blood 5-methyltetrahydrofolate in volunteers.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Homocisteína/sangue , Espectrometria de Massas em Tandem/métodos , Tetra-Hidrofolatos/sangue , Adulto , Estabilidade de Medicamentos , Feminino , Humanos , Limite de Detecção , Modelos Lineares , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
18.
Ann Transl Med ; 8(5): 232, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32309379

RESUMO

BACKGROUND: Diabetic retinopathy (DR), a diabetic vascular complication, is prone to developing into blindness. Ginsenoside Rg1 (GRg1), a major saponin in ginseng, exerts high anti-apoptotic activity. METHODS: This study aimed to explore the protective effects of GRg1 against diabetes-induced retinal damage. Measurements of blood glucose, blood lipids and vascular permeability were performed, as well as assessments of pathological changes, and the retinal thickness of each layer. Retinal cell apoptosis related protein expression levels were measured by immunofluorescence and western blot assays. RESULTS: Our data demonstrated that GRg1 effectively reduced blood glucose and triglyceride levels and maintained normal retinal permeability and physiological structure. GRg1 maintained the thickness of the ganglion cell layer (GCL) and the inner nuclear layer (INL) by reducing cell apoptosis. CONCLUSIONS: These data strongly indicate that GRg1 prevents diabetic retinal changes by decreasing GCL and INL cell apoptosis. GRg1 may be a promising drug for early DR treatment.

19.
Lipids Health Dis ; 19(1): 24, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-32035489

RESUMO

BACKGROUND: The LDL-C lowering effect of ezetimibe has been attributed primarily to increased catabolism of LDL-C via up-regulation of LDL receptor (LDLR) and decreased cholesterol absorption. Recently, ezetimibe has been demonstrated to have reverse cholesterol transport (RCT) promoting effects in mice, hamsters and humans. However, the underlying mechanisms are still not clear. The aim of this study is to investigate whether ezetimibe improves RCT-related protein expression in LDLR-/- hamsters. METHODS: A high-fat diet was used to induce a human-like hyperlipidemia in LDLR-/- hamsters. Lipid profiles were assayed by commercially available kits, and the effects of ezetimibe on lipid metabolism-related protein expression were carried out via western blot. RESULTS: Our data demonstrated that ezetimibe administration significantly reduced plasma total cholesterol (~ 51.6% reduction, P < 0.01) and triglyceride (from ~ 884.1 mg/dL to ~ 277.3 mg/dL) levels in LDLR-/- hamsters fed a high-fat diet. Ezetimibe administration (25 mg/kg/d) significantly promoted the protein expression of cholesterol 7 alpha-hydroxylase A1 (CYP7A1), LXRß and peroxisome proliferator-activated receptor (PPAR) γ; and down-regulated the protein expression of PPARα and PPARß. However, it showed no significant effect on sterol regulatory element-binding protein (SREBP)-1c, SREBP-2, proprotein convertase subtilisin/kexin type 9 (PCSK9), Niemann-Pick C1-like 1 (NPC1L1), and ATP-biding cassette (ABC) G5/G8. CONCLUSION: Ezetimibe may accelerate the transformation from cholesterol to bile acid via promoting CYP7A1 and thereby enhance RCT. As a compensatory mechanism of TG lowering, ezetimibe promoted the protein expression of PPARγ and decreased PPARα and ß. These results are helpful in explaining the lipid-lowering effects of ezetimibe and the potential compensatory mechanisms.


Assuntos
Colesterol 7-alfa-Hidroxilase/metabolismo , Ezetimiba/farmacologia , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Receptores de LDL/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Western Blotting , Colesterol/metabolismo , Cricetinae , Dieta Hiperlipídica , Metabolismo dos Lipídeos/efeitos dos fármacos , Receptores de LDL/deficiência , Receptores de LDL/genética
20.
Chem Biodivers ; 17(2): e1900640, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31805214

RESUMO

The extract of the strain Aspergillus flavipes DL-11 exerted antibacterial activities against six Gram-positive bacteria. During the following bioassay-guided separation, ten diphenyl ethers (1-10), two benzophenones (11-12), together with two xanthones (13-14) were isolated. Among them, 4'-chloroasterric acid (1) was a new chlorinated diphenyl ether. Their structures were elucidated by extensive spectroscopic data analysis, including IR, HR-ESI-MS, NMR experiments, and by comparison with the literature data. All compounds showed moderate to strong antibacterial effects on different Gram-positive bacteria with MIC values that ranged from 3.13 to 50 µg/mL, but none of the compounds exhibited activity against Gram-negative bacteria Vibrio parahaemolyticus ATCC17802 (MIC>100 µg/mL). In particular, the MICs of some compounds are at the level of positive control.


Assuntos
Antibacterianos/química , Aspergillus/química , Benzofenonas/química , Éteres Fenílicos/química , Xantonas/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Aspergillus/metabolismo , Benzofenonas/isolamento & purificação , Benzofenonas/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Conformação Molecular , Éteres Fenílicos/isolamento & purificação , Éteres Fenílicos/farmacologia , Xantonas/isolamento & purificação , Xantonas/farmacologia
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