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1.
Biol Pharm Bull ; 44(7): 926-931, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33952795

RESUMO

Background Astragalus polysaccharide (APS) had shown great promise in anti-tumour activities in our previous studies. The present study was designed to investigate whether APS has synergistic effect with cisplatin on the growth-inhibitory of human nasopharyngeal carcinoma cell lines and the possible mechanism. Methods Here, nasopharyngeal carcinoma cell lines (CNE-1) were divided into CNE-1 group, Cisplatin treatment group (2 µg/mL Cisplatin), APS treatment group (200 µg/mL APS) and combination group (2 µg/mL Cisplatin and 200 µg/mL APS). The proliferation inhibition rate of CNE-1 cells was determined by Cell Counting Kit-8 (CCK-8) method after treatment with different concentrations of APS for 24, 48, and 72 h. Apoptosis rates and cell cycle retardation of cells were detected by flow cytometry. Cell migration and invasion was evaluated by transwell assay. Western blotting and quantitative (q)RT-PCR were performed to detect the expression of Bcl-2, Bax, caspase-3, matrix metalloproteinase-2 (MMP-2), p53 and matrix metalloproteinase-9 (MMP-9) proteins in CNE-1 cells. Results APS have an inhibition on the proliferation of CNE-1 cells with time and dose dependence manner. Both the APS and combination therapy could promote apoptosis of CNE-1 cells, with the count of cells increased in G0/G1 and S phase while decreased in G2/M phase, and inhibited the migration and invasion of CNE-1 cells. Moreover, co-administration of Cisplatin and APS was more efficacious for the antitumor effect than either agent alone, as evidenced by the significant decrease in MMP-9 level and increase in p53. Conclusion APS, in combination with cisplatin, had significantly synergistic growth-inhibitory effect on nasopharyngeal carcinoma cell lines, which may be related to cell cycle and migration induction.


Assuntos
Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Cisplatino/farmacologia , Carcinoma Nasofaríngeo/tratamento farmacológico , Polissacarídeos/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Combinação de Medicamentos , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/metabolismo
2.
J Liposome Res ; 31(1): 79-89, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31691619

RESUMO

In this study, we describe a novel synthesis of galactosylated lipids by lipase catalysis. Lactitol (Lac), galactose (Gal), or N-acetyl galactosamine (GalNAc) was coupled with cholesterol (CHS) as target head groups by enzyme-catalyzed regioselective esterification to produce three kinds of lipids: CHS-1-Gal, CHS-6-Gal, or CHS-6-GalNAc1. The biological effects of galactosylated lipids carrying different constitutional isomers of the pendent sugar species were investigated. LP-1-Gal (liposomes containing 5.0 molar% of CHS-1-Gal) showed strong binding to tetrameric lectins of Ricinus communis agglutinin (RCA120) in vitro, while LP-6-Gal (liposomes containing 5.0 molar% of CHS-6-Gal) and LP-6-GalNAc (liposomes containing 5.0 molar% of CHS-6-GalNAc) did not. After intravenous injection, LP-6-GalNAc, LP-1-Gal and LP-6-Gal rapidly disappeared from the blood and accumulated rapidly in liver (up to 74.88 ± 4.11%, 58.67 ± 5.75%, and 47.66 ± 4.56% of injected dose/g organ within 4 h, respectively). This is significantly higher than the uptake of unmodified liposomes (Unmod-LP) (18.67 ± 6.07%). Pre-injection of asialofetuin significantly inhibits liver uptake of Gal-liposomes (P < 0.01), with the degree of inhibition appearing in the following order: LP-6-GalNAc (73.29%) > LP-1-Gal (67.06%) > LP-6-Gal (53.61%). More importantly, LP-6-GalNAc was preferentially taken up by hepatocytes and the uptake ratio by parenchymal cells (PC) and nonparenchymal cells (NPC) (PC/NPC ratio) was 11.03 higher than LP-1-Gal (7.32), LP-6-Gal (5.83) and Unmod-LP (2.39). We suggest that liposomes containing the novel galactosylated lipid CHS-6-GalNAc have potential as drug delivery carriers for hepatocyte-selective targeting.


Assuntos
Receptor de Asialoglicoproteína/metabolismo , Galactosamina/metabolismo , Galactose/metabolismo , Hepatócitos/metabolismo , Animais , Receptor de Asialoglicoproteína/química , Feminino , Galactosamina/química , Galactose/química , Hepatócitos/química , Lipossomos/química , Lipossomos/metabolismo , Camundongos , Camundongos Endogâmicos , Estrutura Molecular , Tamanho da Partícula , Estereoisomerismo
3.
Molecules ; 26(23)2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34885772

RESUMO

Three novel monoterpenoid indole alkaloids gardflorine A (1), gardflorine B (2), and gardflorine C (3) were isolated from the leaves of Gardneria multiflora. Their structures, including absolute configurations, were established on the basis of spectroscopic methods (MS, UV, IR, 1D and 2D NMR) and circular dichroism experiments. All the compounds were evaluated for their vasorelaxant and acetylcholinesterase (AChE) inhibitory activities. Compound 1 exhibited potent vasorelaxant activity, with an EC50 value of 8.7 µM, and compounds 2 and 3 showed moderate acetylcholinesterase (AChE) inhibitory activities, with IC50 values of 26.8 and 29.2 µM, respectively.


Assuntos
Inibidores da Colinesterase/farmacologia , Loganiaceae/química , Folhas de Planta/química , Alcaloides de Triptamina e Secologanina/farmacologia , Vasodilatadores/farmacologia , Inibidores da Colinesterase/química , Dicroísmo Circular , Espectroscopia de Prótons por Ressonância Magnética , Alcaloides de Triptamina e Secologanina/química , Vasodilatadores/química
4.
Chem Biodivers ; 15(3): e1700577, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29356325

RESUMO

Five new quinolizidine alkaloids, including three sparteine-type alkaloids (1 - 3) and two cytisine-type alkaloids (4 and 5), along with four known ones, were isolated from the roots of Sophora flavescens. Their structures were determined by extensive spectroscopic techniques including IR, UV, NMR, and HR-ESI-MS. All the compounds were evaluated for their antibacterial activities against Staphylococcus aureus and Escherichia coli.


Assuntos
Alcaloides/farmacologia , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Sophora/química , Staphylococcus aureus/efeitos dos fármacos , Alcaloides/química , Alcaloides/isolamento & purificação , Antibacterianos/química , Antibacterianos/isolamento & purificação , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Conformação Molecular , Relação Estrutura-Atividade
5.
Zhonghua Nan Ke Xue ; 23(1): 69-72, 2017 Jan.
Artigo em Zh | MEDLINE | ID: mdl-29658241

RESUMO

OBJECTIVE: To investigate the nursing care of prostate cancer (PCa) patients againstradioactive proctitisinduced byCyberKnifetreatment. METHODS: Sixty-eightPCapatients undergoingCyberKnife treatment in the observation group receivedspecialnursing care againstradioactive proctitis. The nursing measures includedthoserelevant toCyberKnife treatment, prevention ofradioactive proctitis, skin care, and discharge guidance. Meanwhile, another 54 prostate cancer patients received traditional nursing care as controls. We compared the incidence rate and severity of radioactive proctitis between the two groups of patients. RESULTS: The incidence rate of radioactive proctitiswas markedly lower in the observation group than in the control (2.9% vs 13.0%, P<0.05), but no statistically significant difference was observed in the severity of radioactive proctitis between the two groups of patients. CONCLUSIONS: The special nursing care againstCyberKnife-induced radioactiveproctitiscan significantlyreduce the incidence of radioactive proctitis andimprove the effect of CyberKnife treatment of prostate cancer, which therefore deserves wide clinical application.


Assuntos
Proctite/enfermagem , Neoplasias da Próstata/radioterapia , Lesões por Radiação/enfermagem , Radiocirurgia/efeitos adversos , Estudos de Casos e Controles , Humanos , Masculino , Proctite/etiologia , Proctite/prevenção & controle , Lesões por Radiação/prevenção & controle
6.
J Nat Prod ; 78(8): 2036-44, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26222693

RESUMO

The first rotameric monoterpenoid indole alkaloids (MIAs), 1a and 1b, and two unusual dimeric MIAs, 2 and 3, with new dimerization patterns, together with their putative biosynthetic intermediates 4-7, were isolated from the roots of Gelsemium elegans. Compounds 2 and 3 represent the first natural aromatic azo- and the first urea-linked dimeric MIAs, respectively. Their structures and absolute configurations were elucidated by means of NMR spectroscopy, single-crystal X-ray diffraction, and electronic circular dichroism data analyses. The interconverting mechanism of rotamers 1a and 1b was studied by density functional theory computation. Compounds 2 and 3 showed moderate cytotoxic activity against MCF-7 and PC-12 cells, respectively. In addition, a plausible biosynthesis pathway for the new alkaloids was proposed on the basis of the coexistence of their biosynthetic precursors.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Gelsemium/química , Alcaloides de Triptamina e Secologanina/isolamento & purificação , Animais , Cristalografia por Raios X , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Células PC12 , Raízes de Plantas/química , Ratos , Alcaloides de Triptamina e Secologanina/química , Alcaloides de Triptamina e Secologanina/farmacologia , Sais de Tetrazólio/farmacocinética , Tiazóis/farmacocinética
7.
J Asian Nat Prod Res ; 17(3): 274-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25296028

RESUMO

A new phenylpropanoid and a new isoflavone glycoside were isolated from Shenqi Fuzheng Injection. Their structures were elucidated as (αS)-α-ethenyl-4-hydroxy-3-methoxy-benzenemethanol (1) and calycosin 7-O-[α-d-glucopyranosyl (1 â†’ 4)]-ß-d-glucopyranoside (2) by means of spectroscopic methods including UV, IR, HR-ESI-MS, and NMR. The absolute configurations of 1 and 2 were confirmed by quantum chemical calculation and acid hydrolysis.


Assuntos
Medicamentos de Ervas Chinesas/química , Glicosídeos/isolamento & purificação , Isoflavonas/isolamento & purificação , Fenilpropionatos/isolamento & purificação , Glucosídeos , Glicosídeos/química , Isoflavonas/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Fenilpropionatos/química
8.
Zhongguo Zhong Yao Za Zhi ; 38(8): 1188-92, 2013 Apr.
Artigo em Zh | MEDLINE | ID: mdl-23944033

RESUMO

Ten Amaryllidaceae alkaloids were isolated from the bulbs of Lycoris radiata. Their structures were identified as oxovittatine (1), apohaemanthamine (2), 9-O-demethylhomolycorine N-oxide (3), incartine (4), ismine (5), 6-O-methylpretazettine (6), tazettine (7), ungeremine (8), homolycorine (9), and O-methyllycorenine (10) by spectroscopic data analyses. Compound 1 was a new natural product. Compounds 2 and 3 were reported form the genus Lycoris for the first time and compounds 4-6 were isolated form the title plant for the first time.


Assuntos
Alcaloides/química , Lycoris/química , Raízes de Plantas/química , Extratos Vegetais/química
9.
Chem Commun (Camb) ; 59(64): 9742-9745, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37477603

RESUMO

The aromatization mechanisms of ligustilide (1), a versatile monomeric phthalide, were investigated. DFT calculations combined with control experiments prove that the aromatization could result from direct oxidation by triplet oxygen in mild conditions with no catalyst, which is generally thought to be difficult. Moreover, it is predicted that the aromatization could rapidly clear away the harmful-to-organism singlet oxygen, which may be relevant to the general antioxidation activity of phthalides, providing a new point of view to understand the bioactivity from chemical reaction.

10.
Signal Transduct Target Ther ; 8(1): 236, 2023 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-37332010

RESUMO

T lymphopenia, occurring in the early phase of sepsis in response to systemic inflammation, is commonly associated with morbidity and mortality of septic infections. We have previously shown that a sufficient number of T cells is required to constrain Toll-like receptors (TLRs) mediated hyperinflammation. However, the underlying mechanisms remains unsolved. Herein, we unveil that CD4+ T cells engage with MHC II of macrophages to downregulate TLR pro-inflammatory signaling. We show further that the direct contact between CD4 molecule of CD4+ T cells or the ectodomain of CD4 (soluble CD4, sCD4), and MHC II of resident macrophages is necessary and sufficient to prevent TLR4 overactivation in LPS and cecal ligation puncture (CLP) sepsis. sCD4 serum concentrations increase after the onset of LPS sepsis, suggesting its compensatory inhibitive effects on hyperinflammation. sCD4 engagement enables the cytoplasmic domain of MHC II to recruit and activate STING and SHP2, which inhibits IRAK1/Erk and TRAF6/NF-κB activation required for TLR4 inflammation. Furthermore, sCD4 subverts pro-inflammatory plasma membrane anchorage of TLR4 by disruption of MHC II-TLR4 raft domains that promotes MHC II endocytosis. Finally, sCD4/MHCII reversal signaling specifically interferes with TLR4 but not TNFR hyperinflammation, and independent of the inhibitive signaling of CD40 ligand of CD4+ cells on macrophages. Therefore, a sufficient amount of soluble CD4 protein can prevent excessive inflammatory activation of macrophages via alternation of MHC II-TLR signaling complex, that might benefit for a new paradigm of preventive treatment of sepsis.


Assuntos
Antígenos CD4 , Sepse , Humanos , Antígenos CD4/metabolismo , Receptor 4 Toll-Like/genética , Lipopolissacarídeos/metabolismo , Macrófagos/metabolismo , Sepse/genética , Sepse/metabolismo , Inflamação/metabolismo
11.
Int J Pharm ; 624: 121967, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-35777585

RESUMO

In this study, we explored the effect of the hydrophile-lipophile balance (HLB) in the linker unit of Galactose (Gal)/N-acetylgalactosamine (GalNAc) ligands on their affinity toward asialoglycoprotein receptors (ASGPRs). Two Gal/GalNAc ligands with lipophilic linkers-{(5-cholesten-3b-ol)[(2-acetamido-2-deoxy-d-galactopyranose-6-o)sebacate]} (CHS-6-GalNAc) and {(5-cholesten-3b-ol)[(d-galactopyranose-6-o)sebacate]} (CHS-6-Gal)-and two with hydrophilic linkers-{(5-cholesten-yl)[(4-O-b-D-galactopyranosyl)-D-glucitol-6-yl]sebacate} (CHS-1-Gal) and {(5-cholesten-3a-ol)[(2-acetamido-2-deoxy-d-galactopyranose-6-o)3,6-dioxa-octanedioate]} (CHS-PEG2-6-GalNAc)-were synthesized by enzymatic catalysis. Compared with unmodified liposomes, all Gal/GalNAc ligand-modified liposomes showed higher efficiency toward the hepatocyte target as evaluated by weighted-average overall drug-targeting efficiency (Te*) in vivo and HepG2 cell uptake efficiency in vitro. The ligands containing linkers with high HLB values (i.e., CHS-PEG2-6-GalNAc and CHS-1-Gal) exhibited higher ASGPR affinity than those containing linkers with low HLB values (i.e., CHS-6-GalNAc and CHS-6-Gal). We used molecular-dynamics (MD) simulations to investigate the structure-activity relationship between the HLB value of the linker in a ligand and ASGPR affinity. MD simulation results indicated that a Gal/GalNAc ligand with a more hydrophilic linker (i.e., higher HLB value) unit tended to have a higher solvent-accessible surface area (SASA), leading to lower steric hindrance for effective ASGPR recognition. The results of this study will provide an improved design for Gal/GalNAc ligand-based surface-modified liposomes with high ASGPR affinity.


Assuntos
Galactose , Lipossomos , Receptor de Asialoglicoproteína/metabolismo , Hepatócitos/metabolismo , Ligantes , Lipossomos/farmacologia
12.
Nat Prod Res ; 35(19): 3254-3260, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31872787

RESUMO

Two new isoquinoline alkaloids, 6 R,6aS-N-nantenine Nß-oxide (1), 6S,6aS-N-nantenine Nα-oxide (2), along with nine known alkaloids, nantenine (3), oxonantenine (4), protopine (5), nornantenine (6), N-methyl-laurotetanine (7), isocorydine (8), O-methyflavinantine (9), N-methyl-2,3,6-trimethoxymorphinan-dien-7-one Nß-oxide (10) and (+)-10-O-methylhernovine Nß-oxide (11) were isolated from the seeds of Nandina domestica. Their structures were elucidated by extensive analyses of spectroscopic data (IR, UV, HRESIMS, 1 D and 2 D NMR), ECD calculation and comparison with the related literatures. In addition, the cytotoxicity against A549 cells of these alkaloids was determined by the MTT assay.


Assuntos
Alcaloides , Berberidaceae , Isoquinolinas/farmacologia , Células A549 , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Berberidaceae/química , Humanos , Isoquinolinas/isolamento & purificação , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais , Sementes/química
13.
Fitoterapia ; 153: 104997, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34302917

RESUMO

Eight new stilbene dimer xylosides (1-8) and one new flavanol (9), along with seven known ones (10-16) were isolated from the roots of Lysidice rhodostegia. Their structures were elucidated by extensive analysis of spectroscopic data (IR, UV, HR-ESI-MS, 1D and 2D NMR), ECD calculations and acid hydrolysis. Compounds 1-16 were evaluated for their antioxidant activities using DPPH radical-scavenging assay. Especially, compounds 9 and 10 exhibited stronger antioxidant effects than the positive control (vitamin E), with IC50 values of 9.57 ± 1.30 and 13.60 ± 1.47 µM, respectively.


Assuntos
Antioxidantes/farmacologia , Fabaceae/química , Glicosídeos/farmacologia , Polifenóis/farmacologia , Estilbenos/farmacologia , Antioxidantes/isolamento & purificação , China , Glicosídeos/isolamento & purificação , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Raízes de Plantas/química , Polifenóis/isolamento & purificação , Estilbenos/isolamento & purificação
14.
Nat Commun ; 10(1): 1507, 2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30944315

RESUMO

Exhaustion of cytotoxic effector natural killer (NK) and CD8+ T cells have important functions in the establishment of persistent viral infections, but how exhaustion is induced during chronic hepatitis C virus (HCV) infection remains poorly defined. Here we show, using the humanized C/OTg mice permissive for persistent HCV infection, that NK and CD8+ T cells become sequentially exhausted shortly after their transient hepatic infiltration and activation in acute HCV infection. HCV infection upregulates Qa-1 expression in hepatocytes, which ligates NKG2A to induce NK cell exhaustion. Antibodies targeting NKG2A or Qa-1 prevents NK exhaustion and promotes NK-dependent HCV clearance. Moreover, reactivated NK cells provide sufficient IFN-γ that helps rejuvenate polyclonal HCV CD8+ T cell response and clearance of HCV. Our data thus show that NKG2A serves as a critical checkpoint for HCV-induced NK exhaustion, and that NKG2A blockade sequentially boosts interdependent NK and CD8+ T cell functions to prevent persistent HCV infection.


Assuntos
Hepacivirus/imunologia , Hepatite C Crônica/imunologia , Células Matadoras Naturais/imunologia , Subfamília C de Receptores Semelhantes a Lectina de Células NK/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Citocinas/imunologia , Modelos Animais de Doenças , Hepatite C Crônica/virologia , Hepatócitos/virologia , Antígenos de Histocompatibilidade Classe I/imunologia , Interferon gama/imunologia , Ativação Linfocitária/fisiologia , Proteínas de Membrana/imunologia , Camundongos , Distribuição Aleatória
15.
Fitoterapia ; 118: 112-117, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28300700

RESUMO

Five new koumine-type alkaloids (1-5) along with six known ones were isolated from the roots of Gelsemium elegans. Their structures with absolute configurations were elucidated on the basis of NMR spectroscopy and electronic circular dichroism spectral analyses. The inhibitory effects of compounds 1-11 on the viability of three tumor cell lines (A-649, HepG2, and HuH7) were evaluated by the MTT assay.


Assuntos
Gelsemium/química , Alcaloides Indólicos/química , Linhagem Celular Tumoral , Dicroísmo Circular , Humanos , Alcaloides Indólicos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Raízes de Plantas/química
16.
Org Lett ; 6(22): 3925-8, 2004 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-15496065

RESUMO

[reaction: see text] Two types of trisaza-bridged [60]fulleroids have been synthesized for the first time. By means of (13)C NMR, (1)H NMR, MALDI-TOF MS, FTIR, UV-vis, and 2D-NMR (gHSQC, gHMBC, and NOSEY) spectroscopy, they have been shown to be tris[6,5]-opened-aza-bridged adducts with substituents on the same five-membered ring with C(s)() symmetry. Some data of nonlinear optics and electrochemistry for the product are also reported.

17.
Nat Prod Res ; 28(13): 971-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24684175

RESUMO

To investigate the chemical constituents of medicinal plant Uncaria hirsuta, three new monoterpenoid alkaloids, named hirsutanines A-C (1-3), were isolated. Their structures with absolute configurations were elucidated by means of NMR, X-ray diffraction and CD analysis. Compound 3 was the first dimeric monoterpenoid alkaloid obtained from genus Uncaria.


Assuntos
Alcaloides/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Monoterpenos/isolamento & purificação , Uncaria/química , Alcaloides/química , Dicroísmo Circular , Cristalografia por Raios X , Medicamentos de Ervas Chinesas/química , Monoterpenos/química , Ressonância Magnética Nuclear Biomolecular
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