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1.
Chin J Nat Med ; 22(5): 441-454, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38796217

RESUMO

Five novel (9,10-dihydro) phenanthrene and bibenzyl trimers, as well as two previously identified biphenanthrenes and bibenzyls, were isolated from the tubers of Bletilla striata. Their structures were elucidated through comprehensive analyses of NMR and HRESIMS spectroscopic data. The absolute configurations of these compounds were determined by calculating rotational energy barriers and comparison of experimental and calculated ECD curves. Compounds 5b and 6 exhibited inhibitory effects on LPS-induced NO production in BV-2 cells, with IC50 values of 12.59 ± 0.40 and 15.59 ± 0.83 µmol·L-1, respectively. A mechanistic study suggested that these compounds may attenuate neuroinflammation by reducing the activation of the AKT/IκB/NF-κB signaling pathway. Additionally, compounds 3a, 6, and 7 demonstrated significant PTP1B inhibitory activities, with IC50 values of 1.52 ± 0.34, 1.39 ± 0.11, and 1.78 ± 0.01 µmol·L-1, respectively. Further investigation revealed that compound 3a might inhibit LPS-induced PTP1B overexpression and NF-κB activation, thereby mitigating the neuroinflammatory response in BV-2 cells.


Assuntos
NF-kappa B , Orchidaceae , Fenantrenos , Tubérculos , Transdução de Sinais , Fenantrenos/farmacologia , Fenantrenos/química , NF-kappa B/metabolismo , Orchidaceae/química , Transdução de Sinais/efeitos dos fármacos , Tubérculos/química , Animais , Camundongos , Estrutura Molecular , Bibenzilas/farmacologia , Bibenzilas/química , Linhagem Celular , Lipopolissacarídeos/farmacologia , Óxido Nítrico/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Humanos
2.
J Asian Nat Prod Res ; 26(2): 177-188, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38166573

RESUMO

Two pairs of new dihydrophenanthro[b]furan enantiomers blephebibnols G-H (1-2), one new dihydrophenanthro[b]furan derivative blephebibnol I (3), along with four known analogues (4-7), were isolated from the tubers of Bletilla striata. Their structures including the absolute configurations were determined by the combination of spectroscopic data analysis, ECD and NMR calculations. Compounds 1a, 1b, and 2b showed inhibition of NO production in LPS-stimulated BV-2 cells, with IC50 values ranging from 4.11 to 14.65 µM. Further mechanistic study revealed that 1a suppressed the phosphorylation of p65 subunit to regulate the NF-κB signaling pathway. In addition, some compounds displayed selective cytotoxic activities against HCT-116, HepG2, A549, or HGC27 cancer cell lines with IC50 values ranging from 0.1 to 8.23 µM.


Assuntos
Orchidaceae , Transdução de Sinais , Estrutura Molecular , Espectroscopia de Ressonância Magnética , NF-kappa B , Orchidaceae/química
3.
Environ Sci Technol ; 57(38): 14237-14247, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37695749

RESUMO

Interactions and nutrient exchanges among members of microbial communities are important for understanding functional relationships in environmental microbiology. We can begin to elucidate the nature of these complex systems by taking a bottom-up approach utilizing simplified, but representative, community members. Here, we assess the effects of a toxic stress event, the addition of arsenite (As(III)), on a syntrophic co-culture containing lactate-fermenting Desulfovibrio vulgaris Hildenborough and solvent-dechlorinating Dehalococcoides mccartyi strain 195. Arsenic and trichloroethene (TCE) are two highly prevalent groundwater contaminants in the United States, and the presence of bioavailable arsenic is of particular concern at remediation sites in which reductive dechlorination has been employed. While we previously showed that low concentrations of arsenite (As(III)) inhibit the keystone TCE-reducing microorganism, D. mccartyi, this study reports the utilization of physiological analysis, transcriptomics, and metabolomics to assess the effects of arsenic on the metabolisms, gene expression, and nutrient exchanges in the described co-culture. It was found that the presence of D. vulgaris ameliorated arsenic stress on D. mccartyi, improving TCE dechlorination under arsenic-contaminated conditions. Nutrient and amino acid export by D. vulgaris may be a stress-ameliorating exchange in this syntrophic co-culture under arsenic stress, based on upregulation of transporters and increased extracellular nutrients like sarcosine and ornithine. These results broaden our knowledge of microbial community interactions and will support the further development and implementation of robust bioremediation strategies at multi-contaminant sites.


Assuntos
Arsênio , Arsenitos , Tricloroetileno , Solventes , Ácido Láctico
4.
Org Biomol Chem ; 20(23): 4736-4745, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35612380

RESUMO

Two pairs of novel trimeric dihydrophenanthrene-bibenzyl-dihydrophenanthrene enantiomers (1 and2), the first examples of a dihydrophenanthrene dimer linked to a bibenzyl or dihydrophenanthrene through a C-O-C bond (3 and4), and a pair of rare polymers with a bibenzyl connected to C-8' of the dihydrophenanthro[b]furan moiety via a methylene (5), together with four known compounds (6-9) were isolated from the tubers of Bletilla striata. Their structures including the absolute configurations were determined using spectroscopic data analysis and ECD and NMR calculations, combined with the exciton chirality method or the reversed helicity rule. The atropisomerism of dihydrophenanthrenes and related polymers was considered based on their chiral optical properties, and QM torsion profile calculations, which revealed the racemic mixture form of the polymers. Compounds 4, 5b, 6a and 7b significantly inhibited the production of NO in LPS-induced BV-2 cells, with IC50 values ranging from 0.78 to 5.52 µM. Further mechanistic study revealed that 7b suppressed the expression of iNOS, and suppressed the phosphorylation of the p65 subunit to regulate the NF-κB signaling pathway. Furthermore, compounds 2b, 5a, 5b, 7a and 7b displayed significant protein tyrosine phosphatase 1B (PTP1B) inhibitory activities with IC50 values of 3.43-12.30 µM.


Assuntos
Bibenzilas , Orchidaceae , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Bibenzilas/análise , Bibenzilas/química , Bibenzilas/farmacologia , Orchidaceae/química , Tubérculos/química , Polímeros
5.
Appl Opt ; 60(28): 8875-8881, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34613117

RESUMO

In terms of the shortcomings of defect detection based on the electroluminescence of conventional silicon solar panels, which can only be performed under darkroom conditions, a defect detection system that can work under the Sun with any irradiance in all weather is designed. The system electrifies solar panels through a modulated current source, uses high frame rate InGaAs area array detectors for image data acquisition, and transmits images via CameraLink. Using these image data as data sources, a defect display algorithm model is designed. Through experiments, it can effectively collect the defect information of solar panels within the range of 0.2 to 1300W/m2 of sunlight irradiance. Based on this, according to the relationship of the modulated phase difference between the defective points and the nondefective points found in the experiment, an enhancing algorithm for image saliency is proposed. The results show that this algorithm can reduce background interference in an effective way and improve the contrast of defects displayed under high irradiance.

6.
Phytochemistry ; 182: 112609, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33326906

RESUMO

Thirteen undescribed phenanthrene and bibenzyl derivatives, named blestanols A-M, including one pair of biphenanthrene enantiomers, two bis 9,10-dihydrophenanthrene ethers, five pairs of 9,10-dihydrophenanthrene/bibenzyl atropisomers, one racemic 9,10-dihydrophenanthrene/bibenzyl dimer, one 9,10-dihydrophenanthrenebibenzyl ether, two pairs of bibenzyl derivatives, and one stilbene, together with 12 known analogues were isolated from the tubers of Bletilla striata. The structures were elucidated via spectroscopic data analysis. 15 compounds were purified to yield enantiomers (a, b) via chiral-phase HPLC, and their configurations were determined by optical rotation values and the comparison of the experimental and calculated electronic circular dichroism (ECD) curves. Blestanols K-L possessed a cycloheptene moiety, which is rarely observed in bibenzyl derivatives. A putative biosynthetic pathway for the identified components is deduced. Among these compounds, 14 compounds showed inhibition of NO production, with IC50 values ranging from 5.0 to 19.0 µM. Eight compounds displayed selective cytotoxic activities against HCT-116, HepG2, BGC-823, A549 or U251 cancer cell lines, with IC50 values ranging from 1.4 to 8.3 µM. In addition, their structure-activity relationships are discussed briefly.


Assuntos
Bibenzilas , Orchidaceae , Fenantrenos , Bibenzilas/farmacologia , Estrutura Molecular , Fenantrenos/farmacologia , Estereoisomerismo
7.
Org Biomol Chem ; 17(3): 567-572, 2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-30574990

RESUMO

Eight new phenanthrenequinones (four pairs of enantiomers), named bulbocodioidins A-D (1-4), have been isolated from the ethanolic extract of tubers of Pleione bulbocodioides. Their structures, including absolute configurations, were determined by extensive NMR analysis combined with experimental and calculated ECD (electronic circular dichroism) data analyses. Compounds 1-4 possessed a 9(10)H-phenanthren-10(9)-one structure, which is a rarely reported instance from natural sources. Their possible biosynthetic pathway was discussed in the text. The cytotoxic effects of the isolated phenanthrenequinones were evaluated in several human cancer cell lines, and compounds 1a and 4a exhibited marked cytotoxic activities.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Orchidaceae/química , Fenantrenos/farmacologia , Tubérculos/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Fenantrenos/química , Fenantrenos/isolamento & purificação , Estereoisomerismo , Relação Estrutura-Atividade
8.
J Food Sci ; 81(10): H2587-H2596, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27603972

RESUMO

Buddleja officinalis Maxim, one of the most popular herbal medicines in China, is widely prescribed for curing eye diseases for centuries. In this study, the major components of B. officinalis extract (BOE) and their metabolites in rat urine were detected and identified by ultra-high-pressure liquid chromatography coupled with linear ion trap-orbitrap tandem mass spectrometry (UHPLC-LTQ-Orbitrap). A total of 19 compounds, including 8 flavonoids and 11 phenylethanoid glycosides, were confirmed or tentatively identified from BOE. In vivo, 33 components, including 3 prototypes and 30 metabolies, were confirmed or tentatively identified in rat urine samples. The metabolic pathways of different types of compounds were also proposed. This study would effectively narrow the range of potentially bioactive constituents of BOE and shed light to its action mechanism.


Assuntos
Buddleja/química , Flavonoides/análise , Glicosídeos/química , Extratos Vegetais/química , Animais , China , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Extratos Vegetais/urina , Ratos , Ratos Sprague-Dawley , Valores de Referência , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
9.
Molecules ; 21(6)2016 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-27248984

RESUMO

Metabolic study of bioactive compounds that undergo a dynamic and sequential process of metabolism is still a great challenge. Salidroside, one of the most active ingredients of Rhodiola crenulata, can be metabolized in different sites before being absorbed into the systemic blood stream. This study proposed an approach for describing the sequential biotransformation process of salidroside based on comparative analysis. In vitro incubation, in situ closed-loop and in vivo blood sampling were used to determine the relative contribution of each site to the total metabolism of salidroside. The results showed that salidroside was stable in digestive juice, and it was metabolized primarily by the liver and the intestinal flora and to a lesser extent by the gut wall. The sequential metabolism method described in this study could be a general approach to characterizing the metabolic routes in the digestive system for natural products.


Assuntos
Glucosídeos/metabolismo , Fenóis/metabolismo , Animais , Cromatografia Líquida , Suco Gástrico/metabolismo , Glucosídeos/sangue , Glucosídeos/química , Mucosa Intestinal/metabolismo , Masculino , Metabolômica/métodos , Fenóis/sangue , Fenóis/química , Ratos , Espectrometria de Massas em Tandem
10.
Curr Drug Metab ; 17(7): 681-91, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27216792

RESUMO

BACKGROUND: Angiotensin receptor blockers (ARBs) are the most recent class of agents for the treatment of hypertension. However, ARBs may cause a low incidence of headache, upper respiratory infection, back pain, muscle cramps, fatigue, dizziness, and many other side effects. In some cases, such toxicity is associated with pharmacokinetic alterations. METHODS: The cytochrome P450 (CYP) enzyme system plays an important role in a lot of clinically important pharmacokinetic drug interactions. To identify relevant studies on drug-drug and food-drug pharmacokinetic interactions with the ARBs, a literature search of Google Scholar was performed from January 1994 to June 2015, with the following keywords: 'losartan', 'valsartan,' 'candesartan,' 'irbesartan,' 'telmisartan,' 'eprosartan,' 'olmesartan,' and 'azilsartan', combined with the keyword 'pharmacokinetic interactions' and 'CYP'. RESULTS: Based on the literatures published, it has been demonstrated that pharmacokinetic interactions of losartan with other agents are mainly via CYP2C9- and CYP3A4-mediated, the role played by CYP enzyme system in the metabolism of valsartan, candesartan, irbesartan, and azilsartan appears modest, and cytochrome P450 system has no influence on the metabolism of telmisartan, eprosartan, olmesartan. Therefore, according to these pharmacokinetic findings, no dosage adjustment is recommended when eprosartan, telmisartan and olmesartan are combined with other pharmacological agents in patients with hypertension. CONCLUSION: This review summarize the available data on cytochrome P450 - related drug-drug interactions reported in the literature for the eight ARBs. Knowledge of the pharmacokinetic properties of the ARBs should allow the avoidance of the majority of drug interactions without compromising therapeutic benefits.


Assuntos
Antagonistas de Receptores de Angiotensina/farmacocinética , Sistema Enzimático do Citocromo P-450/metabolismo , Animais , Interações Medicamentosas , Humanos
11.
Zhongguo Zhong Yao Za Zhi ; 39(23): 4484-8, 2014 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-25911787

RESUMO

Evaluation of the permeability mainly focuses on intestinal absorption in biopharmaceutics classification system (BCS). It is more complicated that the absorption and metabolism under multicomponent environment in biopharmaceutics classification system of Chinese materia medica (CMMBCS) compared with single component environment, which needs suitable mathematical models to be described. Therefore, with full consideration of existing single component mathematical algorithm combining with the characteristics of intestinal absorption and metabolism, we explored and designed a new mathematical algorithm of intestinal absorption and metabolism of multicomponent drug. Then we put forward a new coefficient, P (influence), the relative change rate of the single component's intestinal absorption and metabolism under multicomponent environment compared with single component environment, which described the influences of intestinal absorption and metabolism of the component under multicomponent environment. Moreover, P (influence) highlights the distinctive characteristics of multicomponent drug's intestinal absorption and metabolism, and lays the foundation for the construction of CMMBCS.


Assuntos
Medicamentos de Ervas Chinesas/farmacocinética , Absorção Intestinal , Mucosa Intestinal/metabolismo , Algoritmos , Medicamentos de Ervas Chinesas/química , Humanos , Intestinos/química , Modelos Teóricos , Solubilidade
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