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1.
Sci Rep ; 14(1): 7613, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38556537

RESUMO

The functionally graded composite structures with viscoelastic polymers inherits the excellent performance of functionally graded composites and also possesses large damping performance, which has broad application prospects in the aerospace and mechanical engineering fields. However, due to the complexity of the structure itself, there is limited literature available on its theoretical modeling for efficient solutions. To predict its dynamic performance, a simplified dynamic model of the functionally graded composite structures with viscoelastic polymers is established. This model takes into account the displacement transfer relationship between the functional graded composite layer and the viscoelastic polymer layer. The governing differential equations are obtained by applying the Navier method and complex modulus theory. These equations are then solved using the Rayleigh-Ritz method. The validity of the theoretical model is confirmed by comparing it with existing literature and the results obtained from ANSYS software. Additionally, the model that has been developed is used to analyze how the graded index and elastic modulus of the structure, as well as its geometric parameters, affect its vibration and damping characteristics.

2.
Environ Pollut ; 347: 123738, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38458522

RESUMO

The pollution of quinolone antibiotics in the marine environment has attracted widespread attention, especially for ofloxacin (OFL) and oxolinic acid (OXO) due to their frequent detection. However, few studies have been conducted to assess the behaviors and microbial community response to these antibiotics in marine sediments, particularly for potential antibiotic-resistant bacteria. In this work, the adsorption characteristics, natural attenuation characteristics, and variation of microbial communities of OFL and OXO in marine sediments were investigated. The adsorption process of antibiotics in sediments occurred on the surface and internal pores of organic matter, where OFL was more likely to be transferred from seawater to sediment compared with OXO. Besides, the adsorption of two antibiotics on sediment surfaces was attributed to physisorption (pore filling, electrostatic interaction) and chemisorption (hydrogen bonding). The natural attenuation of OFL and OXO in marine sediment followed second-order reaction kinetics with half-lives of 6.02 and 26.71 days, respectively, wherein biodegradation contributed the most to attenuation, followed by photolysis. Microbial community structure in marine sediments exposure to antibiotics varied by reducing abundance and diversity of microbial communities, as a whole displaying as an increase in the relative abundance of Firmicutes whereas a decrease of Proteobacteria. In detail, Escherichia-Shigella sp., Blautia sp., Bifidobacterium sp., and Bacillus sp. were those antibiotic-resistant bacteria with potential ability to degrade OFL, while Bacillus sp. may be resistant to OXO. Furthermore, functional predictions indicated that the microbial communities in sediment may resist the stress caused by OFL and OXO through cyano-amino acid metabolism, and ascorbate and aldarate metabolism, respectively. The research is key to understanding fate and bacterial resistance of antibiotics in marine sediments.


Assuntos
Microbiota , Ofloxacino , Ofloxacino/química , Ácido Oxolínico , Adsorção , Antibacterianos/toxicidade , Antibacterianos/química , Sedimentos Geológicos/química , Microbiota/fisiologia , Bactérias
4.
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
5.
Hepatol Commun ; 8(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38206204

RESUMO

BACKGROUND: The impact of HBV infection on the prognosis of patients with intrahepatic cholangiocarcinoma (ICC) remains uncertain, and the underlying mechanism has not been elucidated. This study aims to explore the potential mechanism via clinical perspectives and immune features. METHODS: We retrospectively reviewed 1308 patients with ICC treated surgically from January 2007 to January 2015. Then, we compared immune-related markers using immunohistochemistry staining to obtain the gene expression profile GSE107943 and related literature for preliminary bioinformatics analysis. Subsequently, we conducted a drug sensitivity assay to validate the role of TNFSF9 in the ICC organoid-autologous immune cell coculture system and in the patient-derived organoids-based xenograft platform. RESULTS: The analysis revealed that tumors in patients without HBV infection exhibited greater size and a higher likelihood of lymphatic metastasis, tumor invasion, and relapse. After resection, HBV-infected patients had longer survival time than uninfected patients (p<0.01). Interestingly, the expression of immune-related markers in HBV-positive patients with ICC was higher than that in uninfected patients (p<0.01). The percentage of CD8+ T cells in HBV-positive tissue was higher than that without HBV infection (p<0.05). We screened 21 differentially expressed genes and investigated the function of TNFSF9 through bioinformatics analyses. The expression of TNFSF9 in ICC organoids with HBV infection was lower than that in organoids without HBV infection. The growth of HBV-negative ICC organoids was significantly inhibited by inhibiting the expression of TNFSF9 with a neutralizing antibody. Additionally, the growth rate was faster in HbsAg (-) ICC patient-derived organoids-based xenograft model than in HbsAg (+) group. CONCLUSIONS: The activation of the immune response induced by HBV infection makes the prognosis of HBV-positive patients with ICC differ from that of uninfected patients.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Animais , Humanos , Vírus da Hepatite B , Antígenos de Superfície da Hepatite B , Estudos Retrospectivos , Recidiva Local de Neoplasia , Prognóstico , Colangiocarcinoma/genética , Colangiocarcinoma/cirurgia , Modelos Animais de Doenças , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos , Imunidade
6.
Cell Oncol (Dordr) ; 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38150154

RESUMO

PURPOSE: Uveal melanoma (UM) with BAP1 inactivating mutations has a high risk of metastasis, but the mechanism behind BAP1 deficiency driving UM metastasis is unknown. METHODS: We analyzed the single-cell RNA sequencing (scRNA-Seq) data comprised primary and metastatic UM with or without BAP1 mutations (MUTs) to reveal inter- and intra-tumor heterogeneity among different groups. Then, an immune-competent mouse liver metastatic model was used to explore the role of ITGB2-ICAM1 in BAP1-associated UM metastasis. RESULTS: Cluster 1 tumor cells expressed high levels of genes linked to tumor metastasis, such as GDF15, ATF3, and CDKN1A, all of which are associated with poor prognosis. The strength of communication between terminally exhausted CD8+ T cells and GDF15hiATF3hiCDKN1Ahi tumor cells was enhanced in BAP1-mutated UM, with CellChat analysis predicting strong ITGB2-ICAM1 signaling between them. High expression of either ITGB2 or ICAM1 was a worse prognostic indicator. Using an immune-competent mouse liver metastatic model, we indicated that inhibiting either ICAM1 or ITGB2 prevented liver metastasis in the BAP1-mutated group in vivo. The inhibitors primarily inhibited hypoxia- and ECM-related pathways indicated by changes in the expression of genes such as ADAM8, CAV2, ENO1, PGK1, LOXL2, ITGA5, and VCAN. etc. CONCLUSION: This study suggested that the ITGB2-ICAM1 axis may play a crucial role for BAP1-associated UM metastasis by preserving hypoxia- and ECM- related signatures, which provide a potential strategy for preventing UM metastasis in patients with BAP1 mutation.

7.
Phytomedicine ; 121: 155110, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37776618

RESUMO

BACKGROUND: Neuroinflammation is a vital factor participating in the whole pathogenetic process of diverse neurodegenerative disorders, but accessible clinical drugs are still insufficient due to their inefficacy and side effects. Triterpenoids are reported to possess potential anti-neuroinflammatory activities, and the leaves of Ilex chinensis are a commonly used herbal medicine containing many ursane-type and oleanane-type triterpenoids. However, the novel triterpenoids from I. chinensis and their underlying mechanisms are still elusive. PURPOSE: To isolate novel seco-ursane triterpenoids with anti-neuroinflammatory effects from the leaves of I. chinensis and reveal their underlying mechanisms. STUDY DESIGN AND METHODS: The novel compound was purified by column chromatography and identified by comprehensive spectroscopic experiments. The LPS-induced BV-2 cell model and LPS-induced acute murine brain inflammation model were used to assess the anti-neuroinflammatory effect of the structure and further understand its underlying mechanisms by cell viability, ELISA, Western blot analysis, qRT‒PCR analysis, behavior analysis, H&E staining, and immunofluorescence staining experiments. RESULTS: Ilexchinene is a novel ursane-type triterpenoid with a rare 18,19-seco-ring skeleton that was first isolated and identified from I. chinensis. Ilexchinene evidently reduced the overexpression of inflammatory substances in vitro. A mechanistic study suggested that ilexchinene could decrease NF-κB activation to prevent the formation of the NLRP3 inflammasome in the early neuroinflammatory response; in addition, it could prevent the phosphorylation of ERK and JNK. In vivo, ilexchinene remarkably improved LPS-induced mouse behavioral deficits and diminished the number of overactivated microglial cells. Furthermore, ilexchinene evidently diminished the overexpression of inflammatory substances in mouse brains. A mechanistic study confirmed that ilexchinene markedly suppressed the MAPK/NF-κB pathway to relieve the neuroinflammatory response. CONCLUSION: We identified a novel 18,19-seco-ursane triterpenoid from the leaves of I. chinensis and revealed its underlying mechanism of neuroinflammation for the first time. These findings suggest that ilexchinene might possess promising therapeutic effects in neuroinflammation.


Assuntos
Ilex , Triterpenos , Camundongos , Animais , NF-kappa B/metabolismo , Doenças Neuroinflamatórias , Triterpenos/farmacologia , Triterpenos/metabolismo , Ilex/química , Lipopolissacarídeos/farmacologia , Transdução de Sinais , Inflamação/metabolismo , Microglia
8.
Phytochemistry ; 215: 113832, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37598991

RESUMO

Six undescribed compounds, including three phenolic glycosides (1-3) and three indole alkaloids (4-6), together with ten known alkaloids (7-16) and three known phenolic glycosides (17-19), were isolated from 70% EtOH aqueous extracts of the roots and rhizomes of Clematis chinensis Osbeck. The structures were elucidated by NMR, HRESIMS and X-ray diffraction spectroscopies. The anti-inflammatory activity of these compounds was evaluated, and twelve compounds showed significant inhibitory activity against TNF-α with an inhibition ratio from 47.87% to 94.70% at a dose of 10 µM. Compound 7 exhibited significant inhibitory activity against TNF-α and IL-6 with IC50 values of 3.99 µM and 2.24 µM, respectively. Compound 8 displayed potent anti-inflammatory activity against mouse ear edema induced by croton oil. A mechanistic study suggested that compounds 7 and 8 decreased the activation of the NF-κB signaling pathway to reduce the secretion of inflammatory factors in LPS-induced RAW 264.7 cells.


Assuntos
Clematis , Glicosídeos , Camundongos , Animais , Glicosídeos/farmacologia , Rizoma , Clematis/química , Clematis/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Alcaloides Indólicos
9.
J Colloid Interface Sci ; 652(Pt A): 997-1005, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37639930

RESUMO

The adsorption-catalysis synergy for accelerated conversion of polysulfides is critical toward the electrochemical stability of lithium-sulfur battery (LSB). Herein, a non-metallic polymer network with anion receptor units, trifluoromethanesulfonyl (CF3SO2-) substituted aza-ether, was in-situ integrated on PE separator, working as an efficient host for anchoring lithium thiophosphates (LPS) as redox mediators and polysulfides through Lewis acid-base interaction. The anchored LPS on the modified PE separator displayed a robust chemical adsorption ability towards polysulfides through the formation of SS bond. Meanwhile, LPS decreased the energy barrier of Li2S nucleation and promoted redox reaction kinetics. The battery with LPS decorated separator revealed a long cycling lifespan with a per cycle decay of 0.056 % after 600 cycles, and a competitive initial capacity of 889.1 mAh/g when the of sulfur cathode increased to 3 mg cm-2. This work developed a new design strategy to promote the utilization of lithium phosphorus sulfide compounds in LSB.

10.
Mol Cancer Ther ; 22(9): 1013-1027, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37302522

RESUMO

HER3 is a unique member of the EGFR family of tyrosine kinases, which is broadly expressed in several cancers, including breast, lung, pancreatic, colorectal, gastric, prostate, and bladder cancers and is often associated with poor patient outcomes and therapeutic resistance. U3-1402/Patritumab-GGFG-DXd is the first successful HER3-targeting antibody-drug conjugate (ADC) with clinical efficacy in non-small cell lung cancer. However, over 60% of patients are nonresponsive to U3-1402 due to low target expression levels and responses tend to be in patients with higher target expression levels. U3-1402 is also ineffective in more challenging tumor types such as colorectal cancer. AMT-562 was generated by a novel anti-HER3 antibody Ab562 and a modified self-immolative PABC spacer (T800) to conjugate exatecan. Exatecan showed higher cytotoxic potency than its derivative DXd. Ab562 was selected because of its moderate affinity for minimizing potential toxicity and improving tumor penetration purposes. Both alone or in combination therapies, AMT-562 showed potent and durable antitumor response in low HER3 expression xenograft and heterogeneous patient-derived xenograft/organoid models, including digestive system and lung tumors representing of unmet needs. Combination therapies pairing AMT-562 with therapeutic antibodies, inhibitors of CHEK1, KRAS, and tyrosine kinase inhibitor showed higher synergistic efficacy than Patritumab-GGFG-DXd. Pharmacokinetic and safety profiles of AMT-562 were favorable and the highest dose lacking severe toxicity was 30 mg/kg in cynomolgus monkeys. AMT-562 has potential to be a superior HER3-targeting ADC with a higher therapeutic window that can overcome resistance to generate higher percentage and more durable responses in U3-1402-insensitive tumors.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Imunoconjugados , Neoplasias Pulmonares , Masculino , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Imunoconjugados/farmacologia , Imunoconjugados/uso terapêutico , Receptor ErbB-3 , Receptores ErbB , Linhagem Celular Tumoral
11.
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
12.
Front Pharmacol ; 13: 793087, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401243

RESUMO

Bone homeostasis only exists when the physical function of osteoblast and osteoclast stays in the balance between bone formation and resorption. Bone resorption occurs when the two processes are uncoupled, shifting the balance in favour of bone resorption. Excessive activation of osteoclasts leads to a range of osteolytic bone diseases including osteoporosis, aseptic prosthesis loosening, rheumatoid arthritis, and osteoarthritis. Receptor activator of nuclear factor kappa-B ligand (RANKL) and its downstream signaling pathways are recognized as key mediators that drive the formation and activation of osteoclastic function. Hence, osteoclast formation and/or its function remain as dominant targets for research and development of agents reaching the treatment towards osteolytic diseases. Chrysin (CHR) is a flavonoid with a wide range of anti-inflammatory and anti-tumor effects. However, its effect on osteoclasts remains unknown. In this study, we found the effects of CHR on inhibiting osteoclast differentiation which were assessed in terms of the number and size of TRAcP positive multinucleated osteoclasts (OCs). Further, the inhibitory effects of CHR on bone resorption and osteoclast fusion of pre-OC were assessed by hydroxyapatite resorption pit assay and F-actin belts staining; respectively. Western blotting analysis of RANKL-induced signaling pathways and immunofluorescence analysis for p65 nuclear translocation in response to RANKL-induced osteoclasts were used to analyze the mechanism of action of CHR affecting osteoclasts. Lastly, the murine calvarial osteolysis model revealed that CHR could protect against particle-induced bone destruction in vivo. Collectively, our data strongly suggested that CHR with its promising anti-tumor effects would also be a potential therapeutic agent for osteolytic diseases.

13.
J Environ Manage ; 313: 114980, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35398639

RESUMO

This research aims to evaluate the environmental feasibility of sulfometuron-methyl (SM) as a growth inhibitor for restricting the growth of Spartina alterniflora. To achieve this purpose, the natural attenuation characteristics, ecological risk, degradation pathway, and comprehensive toxicity changes of SM in seawater were investigated under the simulated marine environmental conditions of Jiaozhou Bay, China. The natural attenuation of SM in seawater followed first-order reaction kinetics with a rate constant (K) of 0.0694 d-1 and a half-life of 9.99 days. When photolysis, hydrolysis, and biodegradation pathways act alone, the rate constants K of SM were 0.0167, 0.0143, and 0.0099 d-1 respectively, indicating that their contributions to the total removal of SM decreased in turn. The calculation results of risk quotient (RQ) showed that the seawater containing 10 mg/L of SM demonstrated a very high risk to marine diatom Skeletonema costatum before and after 21 days of attenuation with RQ values of 24.46 and 6.32, respectively, however, the risk to other marine organisms (fish, crustaceans, and bivalves) decreased from moderate (RQ < 1) to low (RQ < 0.01). Four attenuation products of SM were identified and two degradation pathways of SM in seawater were proposed. Based on the rate of inhibition of bioluminescence, SM in seawater was not harmful to Photobacterium phosphoreum T3, whereas the toxicity of seawater containing SM increased with the extension of attenuation time, suggesting the formation of intermediate products with high aquatic toxicity. According to the toxicity values predicted by ECOSAR, the toxicity of one identified attenuation product was higher than that of SM. To the best of our knowledge, this is the first report on the attenuation characteristics and toxicity changes of SM in seawater. The results indicated that the toxicity of both SM and its degradation products to non-target marine organisms should be considered in evaluating the feasibility of SM in controlling coastal Spartina alterniflora.


Assuntos
Diatomáceas , Poluentes Químicos da Água , Animais , Organismos Aquáticos , Cinética , Medição de Risco , Água do Mar/microbiologia , Compostos de Sulfonilureia , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
14.
Nat Prod Res ; 36(8): 1980-1987, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33121294

RESUMO

Two new phenylpropanoid glycosidic compounds (a pair of epimers), named pleionosides K (1) and L (2), were isolated from the pseudobulbs of Pleione bulbocodioides (Franch.) Rolfe. Their structures, including absolute configurations, were elucidated by a combination of MS, NMR data, chemical methods and the comparison of experimental and calculated electronic circular dichroism (ECD). Their possible biosynthetic pathway was discussed in the text. Furthermore, the two compounds exhibited moderate hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced HepG2 cell damage in in vitro assays, with cell survival rates of 25.83% and 28.82% at 10 µM, respectively, and antioxidant effect against H2O2-induced toxicity in human SK-N-SH cell, with increasing viability at 10 µM of 24.9% and 34.6%, respectively.


Assuntos
Peróxido de Hidrogênio , Orchidaceae , Glicosídeos/química , Glicosídeos/farmacologia , Células Hep G2 , Humanos , Peróxido de Hidrogênio/farmacologia , Estrutura Molecular , Orchidaceae/química
15.
Bioorg Chem ; 113: 105025, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34082247

RESUMO

Neuroinflammation is emerging as a crucial reason of major neurodegenerative diseases in recent years. Increasingly evidences have supported that bioactive natural products from traditional Chinese medicines have efficiency for neuroinflammation. Forsythia suspensa, a typical medicinal herb, showed potential neuroprotective and anti-inflammatory properties in previous pharmacological studies. In our research to obtain neuroprotective and anti-inflammatory natural products, three unprecedented C6-C7'/C6-C16' linked phenylethanoidglycoside dimers (1-3), three new phenylethanoidglycosides (4-6), and six known compounds (7-12) were isolated from the fruits of Forsythia suspensa. Their structures were determined by comprehensive spectroscopic data and comparison to the literature data. All isolated compounds were evaluated their neuroprotective and anti-inflammatory activities. Compounds 1 and 10 exhibited significant neuroprotective activities with the cell viability values of 75.24 ± 8.05% and 93.65 ± 10.17%, respectively, for the serum-deprivation and rotenone induced pheochromocytoma (PC12) cell injury. Meanwhile, compound 1 exhibited excellent anti-inflammatory activity against tumor necrosis factor (TNF)-α expression in LPS induced RAW264.7 cells with the IC50 value of 1.30 µM. This study revealed that the bioactive phenylethanoidglycosides may attenuate neuroinflammation through their neuroprotective and anti-inflammatory activities.


Assuntos
Anti-Inflamatórios/química , Forsythia/química , Glicosídeos/química , Fármacos Neuroprotetores/química , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Forsythia/metabolismo , Frutas/química , Frutas/metabolismo , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Conformação Molecular , Fármacos Neuroprotetores/isolamento & purificação , Fármacos Neuroprotetores/farmacologia , Células PC12 , Extratos Vegetais/química , Células RAW 264.7 , Ratos , Fator de Necrose Tumoral alfa/metabolismo
16.
Chin J Nat Med ; 19(5): 376-384, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33941342

RESUMO

Seven new triterpenoid saponins, including five ursane-type saponins, ilexchinenosides R-V (1-5), and two oleanane-type saponins, ilexchinenosides W-X (6-7), with four known triterpenoid saponins (8-11) were isolated from the leaves of Ilex chinensis. Their structures were elucidated by comprehensive spectroscopic 1D and 2D NMR and HR-ESI-MS data. Their sugar moieties were determined by HPLC analysis compared with standards after hydrolysis and derivatization. Compounds 1, 2, 4, 9 and 10 exhibited potential hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced HepG2 cell injury in vitro.


Assuntos
Ilex , Substâncias Protetoras/farmacologia , Saponinas , Triterpenos , Células Hep G2 , Humanos , Ilex/química , Fígado/efeitos dos fármacos , Estrutura Molecular , Compostos Fitoquímicos/farmacologia , Folhas de Planta/química , Saponinas/farmacologia , Triterpenos/farmacologia
17.
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
18.
Bioorg Chem ; 104: 104312, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33142424

RESUMO

Approximately 17 compounds were isolated from a 60% EtOH aqueous extract of the roots and rhizomes of Clematis hexapetala Pall., including three new guaianolide sesquiterpenoids with 5/7/5-fused rings and 3S-configuration (1-3), five new prenylated tetra-substituted phenolic glycosides (4-8) with 6/6-fused 9H-benzopyran skeleton (5) and 6/7-fused 7,10-dihydro-benzoxepin skeleton (6-8), one new isoferulyl glucoside (9), two new furofuran lignan diglucosides (10-11), and six known compounds. The chemical structures of the new compounds were elucidated via spectroscopic data and electronic circular dichroism (ECD) analyses in combination with a modified Mosher's method. The possible biosynthetic relationships of prenylated tetra-substituted phenols were postulated. In the in vitro assays, compound 16 exhibited moderate TNF-α secretion inhibitory activity with IC50 value of 3.419 µM. Compounds 14-16 displayed potent PTP1B enzymatic inhibitory activities with inhibition ratios of 48.30-86.00%. And compound 16 showed significant PTP1B enzymatic inhibition with IC50 value of 4.623 µM.


Assuntos
Anti-Inflamatórios/farmacologia , Clematis/química , Glicosídeos/farmacologia , Lignanas/farmacologia , Fenóis/farmacologia , Rizoma/química , Sesquiterpenos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Relação Dose-Resposta a Droga , Glicosídeos/química , Glicosídeos/isolamento & purificação , Lignanas/química , Lignanas/isolamento & purificação , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos , Estrutura Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Fenóis/química , Fenóis/isolamento & purificação , Raízes de Plantas/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Células RAW 264.7 , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossíntese
19.
J Cell Physiol ; 235(9): 5951-5961, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32026468

RESUMO

Osteoporosis is a devastating disease that features reduced bone quantity and microstructure, which causes fragility fracture and increases mortality, especially in the aged population. Due to the long-term side-effects of current drugs for osteoporosis, it is of importance to find other safe and effective medications. Ellagic acid (EA) is a phenolic compound found in nut galls, plant extracts, and fruits, and exhibits antioxidant and antineoplastic effects. Here, we showed that EA attenuated the formation and function of osteoclast dose-dependently. The underlying mechanism was further discovered by western blot, immunofluorescence assay, and luciferase assay, which elucidated that EA suppressed osteoclastogenesis and bone resorption mainly through attenuating receptor activator of nuclear factor-κB (NF-κB) ligand-induced NF-κB activation and extracellular signal-regulated kinase signaling pathways, accompanied by decreased protein expression of nuclear factor of activated T-cells calcineurin-dependent 1 and c-Fos. Moreover, EA inhibits osteoclast marker genes expression including Dc-stamp, Ctsk, Atp6v0d2, and Acp5. Intriguingly, we also found that EA treatment could significantly protect ovariectomy-induced bone loss in vivo. Conclusively, this study suggested that EA might have the therapeutic potentiality for preventing or treating osteoporosis.


Assuntos
Doenças Ósseas Metabólicas/tratamento farmacológico , Reabsorção Óssea/tratamento farmacológico , Ácido Elágico/farmacologia , Osteoporose/tratamento farmacológico , Animais , Conservadores da Densidade Óssea/farmacologia , Doenças Ósseas Metabólicas/etiologia , Doenças Ósseas Metabólicas/genética , Doenças Ósseas Metabólicas/patologia , Reabsorção Óssea/genética , Reabsorção Óssea/patologia , Diferenciação Celular/efeitos dos fármacos , Humanos , Camundongos , NF-kappa B , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteoporose/etiologia , Osteoporose/genética , Osteoporose/patologia , Ovariectomia/efeitos adversos , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos
20.
Fitoterapia ; 142: 104487, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31987981

RESUMO

Two new tetrahydrobenzocyclooctabenzofuranone lignans (1-2), a new dibenzocyclooctadiene lignan (3) and three new schiartane-type triterpenoids (4-6), together with six known compounds (7-12), were isolated from the roots of Kadsura longipedunculata. Their structures were elucidated by extensive NMR and HRESIMS spectroscopic data analysis. The absolute configurations of these compounds were determined by comparison of the experimental and calculated ECD spectra. Compound 12 exhibited moderate hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced toxicity in HepG2 cells with cell survival rates of 53.04%.


Assuntos
Hepatócitos/efeitos dos fármacos , Kadsura/química , Lignanas/farmacologia , Raízes de Plantas/química , Triterpenos/farmacologia , Acetaminofen/toxicidade , Analgésicos não Narcóticos/toxicidade , Células Hep G2 , Humanos , Lignanas/química , Estrutura Molecular , Triterpenos/química
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