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1.
Biotechnol Bioeng ; 121(3): 1005-1015, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38108196

RESUMO

Bioproduction of chiral amines is limited by low transaminase (TA) activity on nonnatural substrates, leading to the need for protein engineering. To address the challenge of quickly and precisely identifying the engineering targets, a strategy was proposed based on analyzing the mode changes in the high-energy intermediate state (H-state) of the substrate-enzyme complex during catalysis. By substituting the residues with minimal structural changes in catalytically active mode (A-mode) and distance-free mode (F-mode) of the H-state complex with more conserved ones to stabilize it, a TA mutant M5(T295C/L387A/V436A) with 121.9-fold higher activity for synthesizing the (S)-Rivastigmine precursor (S)-1-(3-methoxyphenyl)ethylamine was created. The applicability of this strategy was also validated by engineering another TA for 1.52-fold higher activity and >99% selectivity toward (R)-3-amino-1-butanol biopreparation. The much higher stereoselectivity of the mutant compared with the wild type (28.3%) demonstrated that this strategy is not only advantageous in engineering enzyme activity but also applicable for modulating stereoselectivity.


Assuntos
Engenharia de Proteínas , Transaminases , Transaminases/genética , Transaminases/metabolismo , Aminas/química , Especificidade por Substrato
2.
Front Pharmacol ; 11: 570476, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33364945

RESUMO

The prominent human symbiont Bacteroides fragilis protects animals from intestinal diseases, such as ulcerative colitis, and its capsular polysaccharide plays a key role in reducing inflammation. B. fragilis strain ZY-312 was isolated from the feces of a healthy breast-fed infant, and the zwitterionic capsular polysaccharide zwitterionic polysaccharide, TP2, was extracted. In rats with 2,4-dinitrobenzenesulfonic acid (DNBS)-induced enteritis, TP2 at an optimal dose of 2.5 mg/kg could significantly alleviate enteritis and reduced the degree of intestinal adhesions, the intestinal ulcer area, and the incidence of ulcers in rats. To understand the underlying mechanism, TP2 was labeled with Fluorescein isothiocyanate and orally administered at a dose of 2.5 mg/kg in rats. TP2 was mainly distributed in the cecum and colorectum, but it was not detected in the blood and other organs except that a compound with a molecular weight greater than that of TP2-FITC was found in liver tissue. During the absorption, distribution, metabolism, and excretion, TP2 was indigestible. These results were further confirmed by investigation in the simulated gastric, intestinal fluid, and colonic fluid with fecal microbiota in vitro, where TP2 remained unaltered at different time points. Furthermore, flora composition was analyzed in simulated colonic fluid with TP2 added and it was found that TP2 increased the abundance of Faecalibacterium, Enterococcus romboutsia, and Ruminococcaceae, whereas the abundance of the phylum Proteobacteria represented by Sutterella, Desulfovibrio, and Enterobacteriaceae was decreased. However, the amount of short-chain fatty acids in the simulated colonic fluid was not changed by intestinal flora post-TP2 addition. In conclusion, these findings confirmed that TP2, a capsular polysaccharide of B. fragilis, protects against ulcerative colitis in an undegraded form.

3.
Fitoterapia ; 137: 104268, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31306720

RESUMO

Solanum nigrum L. (also called as European black nightshade) has been traditionally used as folk medicine and food in some regions. Phytochemical investigations of the immature fruits of S. nigrum yielded five steroidal alkaloid glycosides (1-5), including an unprecedented nor-spirosolane type steroidal alkaloid with a five-membered ring A (1) and two novel spirosolane type steroidal alkaloid glycosides (2, 3), together with eight known phenolic compounds (6-13). Their structures were elucidated on the basis of spectroscopic and chemical methods, including IR, NMR, HR-ESI-MS, and GC analyses. Five steroidal alkaloid glycosides were tested for their potential antiproliferative effects against HL-60, U-937, Jurkat, K562, and HepG2 cell lines and inhibitory activities on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in a macrophage cell line RAW 264.7. Compound 1 exhibited significant inhibition on NO production with an IC50 value of 23.4 ±â€¯2.0 µM, compared to positive control indomethacin (IC50, 47.40 ±â€¯4.50 µM). Compound 4 exhibited significant cytotoxicity against all tested cell lines.


Assuntos
Alcaloides/farmacologia , Glicosídeos/farmacologia , Solanum nigrum/química , Esteroides/farmacologia , Alcaloides/isolamento & purificação , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , China , Frutas/química , Glicosídeos/isolamento & purificação , Humanos , Camundongos , Estrutura Molecular , Óxido Nítrico/metabolismo , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Células RAW 264.7 , Esteroides/isolamento & purificação
4.
Steroids ; 148: 11-18, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31026467

RESUMO

Phytochemical investigations on the bulbs of Chinese onion led to the isolation of three new furostanol saponins (1, 2, 5) together with seven known furostanol saponins (3, 4, 6-10). Their chemical structures were elucidated on the basis of spectroscopic and chemical methods, including IR, MS, NMR, and GC analyses. The anti-proliferative and anti-inflammatory activities of the isolates were evaluated. Compounds 7-10 showed potential anti-proliferative activities against human cancer cell lines (HepG2, A549, SPC-A-1, MGC80-3, MDA-MB-231, SW620 and CNE-1) with IC50 values below 30 µM. Compounds 4 and 7 could induce G2/M cell-cycle arrest and apoptosis through mitochondria-mediate pathway in HepG2 cells. Compounds 7 and 10 showed strong inhibitory effects against LPS induced NO production in RAW264.7 cells with IC50 values of 2.01 ±â€¯1.40 µM and 2.49 ±â€¯1.54 µM, respectively.


Assuntos
Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Cebolas/química , Saponinas/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos , Mitocôndrias/metabolismo , Conformação Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Células RAW 264.7 , Saponinas/química , Saponinas/isolamento & purificação , Relação Estrutura-Atividade
5.
Phytomedicine ; 42: 83-89, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29655701

RESUMO

BACKGROUND: Our previous study has revealed that the spirostanol saponins isolated from the rhizomes of Rohdea chinensis (Baker) N. Tanaka (synonym Tupistra chinensis Baker) (Convallariaceae) (a reputed folk medicine) exhibited potent antiproliferative activity. However, the underlying mechanism of purified saponins remains unclear. More studies are necessary to assess the apoptosis and autophagy activities of the saponins from R. chinensis and clarify their antiproliferative mechanisms. PURPOSE: The present study certificated the potential antiproliferative activity and mechanism of 5ß-spirost-25(27)-en-1ß,3ß-diol-1-O-α-L-rhamnopyranosyl-(1→2)- ß-D-xylopyranosyl-3-O-α-L-rhamnopyranoside (SPD), a spirostanol saponin from R. chinensis, against human acute promyelocytic leukemia cells (HL-60). METHODS: The antiproliferative activity of SPD in vitro was evaluated by MTT assay compared with cis-dichlorodiammineplatinum (II). The autophagic activity was assessed using MDC staining and western blot, cell apoptosis inspection was detected by Annexin V-FITC/PI double staining and the mitochondrial membrane potential was detected by JC-1 fluorescence dye combined with flow cytometry. The potential mechanisms for protein levels of apoptosis and autophagy were evaluated by western blot. RESULTS: Treatment of HL-60 cells with SPD resulted in growth inhibition (IC50 value of 2.0 ± 0.2 µM, after 48 h treatment) and induction of apoptosis and autophagy. Results from Annexin V-FITC/PI double-staining assay and mitochondrial membrane potential detection showed that apoptosis was happened after SPD treatment. The regulation of caspase-3, Bax, Bcl-2, PARP following SPD treatment contributed to the induction of mitochondria-dependent apoptosis. Meanwhile, SPD induced autophagy related with Akt/mTOR/p70S6K signaling and activated of AMPK signaling pathway. Furthermore, blocking autophagy with bafilomycin A1 reduced the cytotoxicity of SPD in HL-60 cells. CONCLUSION: The antiproliferative, apoptosis and pro-death autophagy activities of SPD suggested that spirostanol saponins from R. chinensis would be a potential cytotoxic candidate against acute promyelocytic leukemia.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Autofagia/efeitos dos fármacos , Saponinas/farmacologia , Espirostanos/farmacologia , Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Rizoma/química , Saponinas/química , Espirostanos/química , Serina-Treonina Quinases TOR/metabolismo
6.
Phytochemistry ; 148: 87-96, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29421515

RESUMO

Seven previously undescribed steroidal glycosides, along with three known congeners were isolated from the unripe berries of Solanum nigrum L. (Solanaceae). Their structures were elucidated on basis of 1D and 2D NMR, HR-ESI-MS spectroscopic data and GC analysis after acid hydrolysis. The potential inhibitory effects on nitric oxide (NO) production induced by lipopolysaccharide in RAW 264.7 cell line and the anti-proliferative activities against five cancer cell lines (HL-60, U-937, Jurkat, K562 and HepG2) were evaluated. Seven compounds exhibited inhibition activities on NO production with IC50 values ranging from 11.33 to 49.35 µM. Structure-activity relationships of the isolated compounds were also discussed.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Frutas/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Solanum nigrum/química , Esteroides/isolamento & purificação , Esteroides/farmacologia , Animais , Anti-Inflamatórios/química , Glicosídeos/química , Células HL-60 , Células Hep G2 , Humanos , Concentração Inibidora 50 , Células K562 , Camundongos , Estrutura Molecular , Óxido Nítrico/metabolismo , Raízes de Plantas/química , Células RAW 264.7 , Esteroides/química , Relação Estrutura-Atividade
7.
Food Chem ; 241: 215-221, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28958521

RESUMO

Durian, known for its abundant nutrition, is a delicious fruit from Southeast Asia with increasing popularity worldwide. In this study, a series of chromatographic methods and bioactivity assays were applied to identify major compounds from durian shells. Two new triterpenoids, two new phenolics, and seven new glycoside esters, as well as sixteen known compounds, were isolated and identified. Anti-inflammatory activities were assayed and evaluated for the isolated compounds. Most of the isolated compounds exhibited pronounced inhibitory activities on lipopolysaccharides-induced NO production in RAW 264.7 cells. The results indicated that durian shells could serve as anti-inflammatory agents for functional food or medicinal use. This study additionally provided motivation for the ecological protection of durian shells.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Bombacaceae , Glicosídeos/isolamento & purificação , Triterpenos/isolamento & purificação , Sudeste Asiático , Frutas
8.
Fitoterapia ; 121: 229-234, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28782581

RESUMO

Four new phenylpropanoids (1-4) along with ten known phenolics were isolated and purified from the roots of hairy fig (Ficus hirta Vahl.). Their structures were elucidated by the extensive spectroscopic analysis and chemical degradation. The anti-inflammatory activities of the purified compounds were evaluated. Results indicated that the extracts and some purified compounds exhibited pronounced inhibitory effects on the lipopolysaccharides (LPS) induced nitric oxide (NO) production in murine macrophage RAW 264.7 compared to indomethacin, which suggested that hairy fig could be served as an anti-inflammatory agent for health products.


Assuntos
Anti-Inflamatórios/farmacologia , Ficus/química , Macrófagos/efeitos dos fármacos , Fenóis/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Camundongos , Estrutura Molecular , Óxido Nítrico/metabolismo , Fenóis/isolamento & purificação , Extratos Vegetais/química , Raízes de Plantas/química , Células RAW 264.7
9.
Phytochemistry ; 143: 81-86, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28780427

RESUMO

Six previously undescribed piperidine alkaloids were isolated from the rhizomes of Alocasia macrorrhiza (L.) Schott. Their structures were elucidated based on 1D and 2D NMR, IR, HR-ESI-MS spectroscopic analysis and the application of a modified Mosher method. All isolated alkaloids were evaluated for cytotoxicity against five human cancer cell lines (CNE-1, Detroit 562, Fadu, MGC-803, and MCF-7) using the MTT method. Only one compound exhibited cytotoxic effects against Detroit 562, Fadu, and MCF-7 cell lines with IC50 values less than 10 µM.


Assuntos
Alcaloides/isolamento & purificação , Alocasia/química , Antineoplásicos Fitogênicos/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Piperidinas/isolamento & purificação , Alcaloides/química , Alcaloides/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Células MCF-7 , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Piperidinas/química , Piperidinas/farmacologia , Rizoma/química
10.
Phytomedicine ; 28: 10-18, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28478808

RESUMO

BACKGROUND: Harmine, a ß-carboline alkaloid from Peganum harmala, has multiple anti-tumor activities, especially for its folk therapy for digestive system neoplasm. However, the underlying mechanism of harmine on gastric cancer remains unclear. PURPOSE: To illuminate the potential anti-tumor activity and mechanism of harmine against gastric cancer cells. METHODS/STUDY DESIGNS: The anti-proliferative activity of harmine in vitro was evaluated by MTT assay. The autophagic activity induced by harmine was assessed using GFP-LC3 transfection. FITC/PI double staining was applied for the apoptosis inspection. The mitochondrial membrane potential was detected by JC-1 fluorescence probe. The potential mechanisms for proteins level in autophagy and apoptosis were analyzed by Western blot. RESULTS: Harmine exhibited potent effects on both autophagy and apoptosis. Treatment with harmine could enhance dots of GFP-LC3 in cells. Meanwhile, the process had connection with Beclin-1, LC3-II, and p62 by the inhibition of Akt/mTOR/p70S6K signaling. However, high concentration of harmine led to apoptosis characterized by the propidium/Annexin V-positive cell pollution, cell shrunk and the collapse of mitochondrial membrane potential. The regulation of Bcl-2, Bax and the gathering of cleaved-PARP, cleaved-caspase 3 and cleaved-caspase 9 contributed to the induction of apoptosis. In addition, 10µM LY294002 (a specific inhibitor of PI3K/Akt) combination with 40µM harmine significantly increased the cytotoxicity to the gastric cancer cells and up-regulated both the apoptosis-related protein (cleaved-PARP, cleaved-caspase-3) and autophagy-related protein (Beclin-1, LC3-II, and p62). Adding the inhibitor of autophagy, 3-MA or BafA1, increased the viability of harmine-exposured gastric cancer cells, which confirmed the role of autophagy played in the gastric cancer cell death induced by harmine. CONCLUSION: Harmine might be a potent inducer of apoptosis and autophagy, which offered evidences to therapy of harmine in gastric carcinoma in the folk medicine.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Autofagia/efeitos dos fármacos , Harmina/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Proteína Beclina-1/metabolismo , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
11.
J Agric Food Chem ; 65(21): 4262-4272, 2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28486801

RESUMO

Solanum nigrum L. or European black nightshade (Solanum genus) is a common weed of crops and gardens. The berries and leaves of S. nigrum L. are consumed as food or vegetable in some regions and reported to possess a range of biological activities. In this study, nine new steroidal saponins, solanigrosides Y1-Y9 (1-6, 10-12), together with seven known congeners, were isolated from the berries of S. nigrum. Their potential inhibitory effects on nitric oxide (NO) and IL-6 and IL-1ß production induced by lipopolysaccharide (LPS) in macrophages cell line RAW 264.7 were evaluated. Compound 1 exhibited significant inhibition on NO production with an IC50 value of 9.7 µM, and some compounds exhibited significant inhibition effects on the LPS-induced IL-6 and IL-1ß production. These results suggest that the steroidal saponins from berries of S. nigrum demonstrated pronounced anti-inflammatory activity and might be explored as a healthy benefit agent.


Assuntos
Anti-Inflamatórios/análise , Extratos Vegetais/análise , Saponinas/análise , Solanum nigrum/química , Animais , Anti-Inflamatórios/farmacologia , Frutas/química , Interleucina-6/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Óxido Nítrico/imunologia , Extratos Vegetais/farmacologia , Células RAW 264.7 , Saponinas/farmacologia
12.
Fitoterapia ; 117: 126-132, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28161134

RESUMO

Five new lignanamides (1-5), and one new monoindole alkaloid (6), along with eight known compounds (7-14) were isolated and identified from the rhizomes of Alocasia macrorrhiza (giant taro). All purified compounds were evaluated for their inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 cells, and the antiproliferative activities against human nasopharyngeal carcinoma epithelial (CNE-1), human gastric carcinoma (MGC-803), and human breast cancer (MCF-7) cell lines by MTT method. Compounds 2, 4, 7 and 8 exhibited significant inhibitory effects on NO production with the IC50 values of 2.35±0.38, 9.20±0.94, 3.45±0.39 and 7.96±0.56µM, respectively. The results suggested the lignanamides and monoindoles might be responsible for the anti-inflammatory activity of giant taro and might be potential anti-inflammatory candidates.


Assuntos
Alocasia/química , Anti-Inflamatórios/química , Indóis/química , Lignanas/química , Animais , Anti-Inflamatórios/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Indóis/isolamento & purificação , Lignanas/isolamento & purificação , Lipopolissacarídeos , Camundongos , Estrutura Molecular , Óxido Nítrico/metabolismo , Células RAW 264.7 , Rizoma/química
13.
Steroids ; 116: 28-37, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27770616

RESUMO

Phytochemical investigations of the rhizome of Tupistra chinensis led to the isolation of ten new furostanol saponins along with fourteen known spirostanols. Their chemical structures were elucidated on the basis of spectroscopic and chemical methods, including IR, NMR, MS, and GC analyses. The antiproliferative effects against FaDu and Detroit 562 cell lines and inhibitory activities on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in a macrophage cell line RAW 264.7 were assayed for all the isolated compounds. Compound 14 exhibited significant antiproliferative effects against FaDu and Detroit 562 cells with IC50 values of 1.1±0.1 and 1.2±0.1µM, respectively. Compounds 1, 2, 6, 13, 16, 19 and 24 exhibited inhibitory effects on NO production with IC50 values ranging from 15.7 to 46.2µM.


Assuntos
Liliaceae/química , Rizoma/química , Saponinas/farmacologia , Animais , Anti-Inflamatórios , Linhagem Celular , Humanos , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Células RAW 264.7 , Saponinas/química
14.
J Agric Food Chem ; 64(40): 7475-7480, 2016 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-27643634

RESUMO

Mango (Mangifera indica L.) is a succulent tropical fruit. Bioactive phytochemical investigation has been carried out to the leaves of mango. Three new benzophenone glycosides, along with 14 known compounds, were purified and identified. The novel benzophenones were elucidated to be 2,4,4',6-tetrahydroxy-3'-methoxybenzophenone-3-C-ß-d-glucopyranoside (1), 4,4',6-trihydroxybenzophenone-2-O-α-l-arabinofuranoside (7), and 4',6-dihydroxy-4-methoxybenzophenone-2-O-(2″),3-C-(1″)-1″-desoxy-α-l-fructofuranoside (11). The α-glucosidase inhibitory, NO production inhibitory, and antioxidant activities were assessed for the purified benzophenones and triterpenoids. Some benzophenones showed moderate α-glucosidase and NO inhibitory activities. The IC50 value of the α-glucosidase inhibitory of isolated compounds 1, 13, and 14 were 284.93 ± 20.29, 239.60 ± 25.00, and 297.37 ± 8.12 µM, respectively. Most compounds showed moderate effects to reduce the NO content in 50 and 100 µM. The above results of bioactivity powerfully demonstrated the phytochemicals from mango, especially benzophenones, probably partially rational for its antidiabetes and anti-inflammatory.


Assuntos
Benzofenonas/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Mangifera/química , Óxidos de Nitrogênio/metabolismo , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Benzofenonas/química , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores de Glicosídeo Hidrolases/química , Macrófagos/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Camundongos , Estrutura Molecular , Folhas de Planta/química , alfa-Glucosidases/metabolismo
15.
Int J Oncol ; 49(5): 1911-1920, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27633959

RESUMO

Near-infrared fluorescence (NIRF) imaging is a novel imaging modality that allows for detection and real­time monitoring of various pathophysiological states. IR-780 iodide has been used as an ideal platform to construct theranostic agents for cancer imaging and therapy. Abiraterone is a 17α­hydroxylase/C17, 20­lyase (CYP17) inhibitor that has been approved for use in patients with prostate cancer after androgen deprivation therapy. We report the synthesis and characterization of IR-780 conjugated abiraterone for the dual purpose of prostate cancer imaging and therapy. The new compound Abi-780 retained the excellent photophysical characteristics and NIRF imaging property of IR-780 dye. Abi-780 preferentially accumulated in plasmonic organelles of prostate cancer cells but not in normal prostate epithelial cells. Dose-dependent inhibition of cultured prostate cancer cells by Abi-780 was found. Abi-780 at 20 µM significantly reduced the capabilities of colony formation and migration/invasion potential as well as increasing the apoptosis rate of prostate cancer cells. NIRF imaging using Abi-780 selectively identified the tumors in mice bearing prostate cancer xenografts. Moreover, Abi-780 treatment significantly retarded the tumor growth. No severe systemic toxicity was observed in mice with daily injection of high-dose Abi-780 for one month. In conclusion, biocompatible Abi-780 is highly effective both in prostate cancer imaging and therapy. Constructing theranostic agents using the NIRF dye platform holds great promise in accurate diagnosis and targeted treatment of cancer.


Assuntos
Androstenos/farmacologia , Indóis/química , Imagem Óptica/métodos , Neoplasias da Próstata/diagnóstico por imagem , Androstenos/química , Animais , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Citometria de Fluxo , Corantes Fluorescentes/química , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/tratamento farmacológico , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Tumour Biol ; 37(10): 14153-14163, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27539728

RESUMO

The purpose of this study was to prepare tumor-specific dual-mode nanobubbles as both ultrasound contrast agents (UCAs) and near-infrared fluorescence (NIRF) imaging agents for female tumors. Recent studies have demonstrated the conjugation of anti-tumor ligands on the surface of nanobubbles for use as molecule-targeting ultrasound contrast agents for tumor visualization. However, this complicated procedure has also posed a challenge to nanobubble stability. Thus, in the present study, we combined the fluorescent dye, NIRF IR-780 iodide, which has lipid solubility and tumor-targeting characteristics, with the phospholipid film of nanobubbles that we constructed. We then characterized the physical features of the IR-780-nanobubbles, observed their tumor-targeting capacity in multiple female tumor cell types in vitro, and verified their capability for use in tumor-specific ultrasound contrast imaging and NIRF imaging in vivo. The results showed that the new IR-780-nanobubbles had a uniform nano-size (442.5 ± 48.6 nm) and stability and that they were safe and effective at NIRF imaging and ultrasound imaging in vitro. The IR-780-nanobubbles were found to automatically accumulate on different female tumor cells in vitro with a considerable targeting rate (close to 40 %) but did not accumulate on cardiac muscle cells used as a negative control. Importantly, the IR-780-nanobubbles can detect female tumors precisely via dual-mode imaging in vivo. In conclusion, the new dual-mode IR-780-nanobubbles are stable and have potential advantages in non-invasive tumor-specific detection for female tumors via contrast-enhanced ultrasound and NIRF imaging.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Meios de Contraste , Indóis , Nanopartículas/química , Ultrassonografia/métodos , Animais , Apoptose , Neoplasias da Mama/metabolismo , Proliferação de Células , Feminino , Citometria de Fluxo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/administração & dosagem , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Sci Rep ; 6: 31633, 2016 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-27530890

RESUMO

Tupistra chinensis is widely distributed in southwestern China and its rhizome is a famous folk medicine for the treatment of carbuncles and pharyngitis. Its chemical identity of potent antiproliferative and anti-inflammatory constituents has been carried out in this study. Twenty-three polyhydroxylated spirostanol saponins, including nine novels, were isolated and identified. The new spirostanol saponins were elucidated as spirost-25(27)-en-1ß,2ß,3ß,4ß,5ß-pentol-2-O-ß-D-xylopyranoside (1), spirost-25(27)- en-1ß,2ß,3ß,4ß,5ß-pentol-2-O-α-L-arabinopyranoside (2), spirost-25(27)-en- 1ß,3α,5ß-triol (12), spirost-25(27)-en-1ß,3α,4ß,5ß,6ß-pentol (13), spirost-25(27)-en- 1ß,2ß,3ß,5ß-tetraol-5-O-ß-D-glucopyranoside (16), 5ß-spirost-25(27)-en-1ß,3ß-diol- 3-O-ß-D-glucopyranosyl-(1 → 4)-ß-D-glucopyranoside (17), (25R)-5ß-spirostan- 1ß,3ß-diol-3-O-ß-D-glucopyranosyl-(1 → 6)-ß-D-glucopyranoside (18), (25R)-5ß- spirostan-1ß,3ß-diol-3-O-ß-D-fructofuranosyl-(2 → 6)-ß-D-glucopyranoside (19), 5ß-spirost-25(27)-en-3ß-ol-3-O-ß-D-glucopyranosyl-(1 → 4)-ß-D-glucopyranoside (20). The antiproliferative effects against seven human cancer cell lines and inhibitory activities on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in a macrophage cell line RAW 264.7 were assayed for all the isolated compounds. Compounds 17, 19 and 21 exhibited potential antiproliferative activities against all of human cancer cell lines tested. Compounds 21 showed significant inhibition on NO production with IC50 values of 11.5 µM. These results showed that the spirostanol saponins isolated from the dried rhizomes of T. chinensis have potent antiproliferative and anti-inflammatory activities and T. chinensis might be used as anticancer and.anti-inflammatory supplement.


Assuntos
Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Asparagaceae/química , Saponinas/farmacologia , Espirostanos/farmacologia , Anti-Inflamatórios/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , China , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Células Hep G2 , Humanos , Células K562 , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Óxido Nítrico/biossíntese , Plantas Medicinais/química , Rizoma/química , Saponinas/isolamento & purificação , Espirostanos/isolamento & purificação
18.
J Agric Food Chem ; 64(21): 4273-9, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27159409

RESUMO

Durian, known as the king of fruits, is native to Southeast Asia and popular in many countries. Bioactivity-guided fractionation of the peel of durian was applied to determine its bioactive constituents. Four novel phenolics, along with 16 known, were purified and identified. Four novel phenolics were elucidated to be durianol A (1), durianol B (2), durianol C (3), and 5'-methoxy-7'-epi-jatrorin A (4), respectively. The antioxidant and NO inhibitory activities were evaluated for the isolated phenolics. Some phenolics showed significant antioxidant activity in the DPPH and superoxide anion radical scavenging capacity assay. Most of the phenolics revealed pronounced inhibitory effects on NO production in murine RAW 264.7 cells induced by LPS, which showed more potent NO inhibitory activity compared to indomethacin. The results strongly demonstrated that the phenolics may be partially responsible for durian's NO inhibitory activity.


Assuntos
Antioxidantes/química , Bombacaceae/química , Óxido Nítrico/antagonistas & inibidores , Fenóis/química , Animais , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Frutas/química , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Fenóis/isolamento & purificação , Fenóis/farmacologia , Células RAW 264.7
19.
Oncotarget ; 7(26): 40174-40188, 2016 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-27233075

RESUMO

BKCa is a large conductance calcium activated potassium channel promoting prostate cancer cell proliferation, although the mechanism is not fully elucidated. In addition, whether BKCa is involved in metastasis of prostate cancer remains to be explored. Here, we report that BKCa is overexpressed in prostate cancer. BKCa expression positively correlates with Ki67 index and gleason score of prostate cancer. Upregulation of BKCa promoted proliferation, migration and invasion of prostate cancer cells. On the contrary, downregulation of BKCa inhibited growth and metastasis of prostate cancer cells both in vitro and in vivo. Moreover, the ion-conducting function of BKCa contributed moderately to prostate cancer proliferation and migration, although, this was not the primary mechanism. BKCa action was mainly mediated through forming a functional complex with αvß3 integrin. The BKCa/αvß3 integrin complex promoted FAK phosphorylation independent of the channel activity. Overexpression of BKCa enhanced its association with αvß3 integrin and FAK which increased FAK phosphorylation. Conversely, disrupting the complex by downregulation of BKCa reduced FAK phosphorylation. Finally, blocking of αvß3 integrin or p-FAK activity using LM609 or Y15 markedly abrogated BKCa-enhanced cell proliferation and migration. Taken together, these results suggest that targeting BKCa/αvß3/FAK may inaugurate innovative approaches to inhibit prostate cancer growth and metastasis.


Assuntos
Quinase 1 de Adesão Focal/metabolismo , Integrina alfaVbeta3/metabolismo , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Neoplasias da Próstata/patologia , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Nus , Invasividade Neoplásica , Metástase Neoplásica , Técnicas de Patch-Clamp , Fosforilação , Neoplasias da Próstata/metabolismo , Transdução de Sinais
20.
Steroids ; 108: 39-46, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26898537

RESUMO

Phytochemical investigations of the rhizome of Tupistra chinensis led to the isolation of six new spirostanol saponins, one new spirostanol, along with eight known spirostanols. Their chemical structures were elucidated on the basis of spectroscopic and chemical methods, including IR, NMR, MS, and GC analyses. The antiproliferative effects against five human cancer cell lines were assayed for all the isolated compounds. Compounds 8, 12 and 15 showed potent cytotoxic activities against K562 cells. The isolated compounds were evaluated for their inhibitory activities on nitric oxide (NO) production induced by lipopolysaccharide in a macrophage cell line RAW 264.7. Compounds 2 and 12 showed significant inhibition on NO production with IC50 values of 16.1±1.8 and 13.5±1.2 µM, respectively.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Asparagaceae/química , Rizoma/química , Saponinas/química , Saponinas/farmacologia , Espirostanos/química , Animais , Antineoplásicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Humanos , Células K562 , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Óxido Nítrico/biossíntese , Células RAW 264.7 , Saponinas/isolamento & purificação
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