Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20.686
Filtrar
1.
An Acad Bras Cienc ; 91(3): e20180654, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365653

RESUMO

Candida albicans is the most frequent fungal species that causes infections in humans. Fluconazole is the main antifungal used to treat Candida infections, and its prolonged and indiscriminate use for the last decades are the most established causes which originated resistant strains. Fungal drug resistance is associated to alterations in ERG11 gene and overexpression of multidrug resistance (MDR) transporters belonging to two families: ATP-binding cassette (ABC) and Major Facilitator Superfamily (MFS). To evaluate the role of MFS transporters in azoles resistance of C. albicans clinical strains, this study aimed to analyze four Candida albicans clinical isolates from the University Hospital in Juiz de Fora (Minas Gerais/Brazil), selected in our previous study as they were unaffected by FK506, an ABC pumps inhibitor. In a primary investigation on MFS proteins overexpression, the extrusion of fluorescent substrates (rhodamine 6G and nile red) was analyzed by fluorescence microscopy and flow cytometry. Results suggest participation of MFS transporters in azole resistance of C. albicans isolates and indicate the existence of secondary resistance mechanisms. Therefore, this study contributes to the information about Candida albicans infections in Brazil and reinforces the importance of epidemiological studies focusing on an improved understanding of the disease and further resistance reversion.


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Candida albicans/efeitos dos fármacos , Proteínas de Membrana Transportadoras/metabolismo , Azóis/classificação , Transporte Biológico/efeitos dos fármacos , Citometria de Fluxo , Humanos , Proteínas de Membrana Transportadoras/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Microscopia de Fluorescência , Centros de Atenção Terciária
2.
J Agric Food Chem ; 67(32): 8839-8846, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31334651

RESUMO

Natural products are one of the main sources for discovering new lead compounds. We previously reported that cinnamon extract has a promising effect in regulating lipid tissue volume and insulin sensitivity in vivo. However, its effective component and the underlying mechanism are not known. In the present study, we analyzed the effect of different components of cinnamon on regulating insulin sensitivity in 3T3-L1 adipocytes. Functional assay revealed that, of the six major components of cinnamon extracts, the B-type procyanidin, procyanidin C1, improves the differentiation of 3T3-L1 cells (TG content: 1.10 ± 0.09 mM at a dosage of 25 µM vs 0.67 ± 0.02 mM in vehicle group, p < 0.001) and promotes insulin-induced glucose uptake (8.58 ± 1.43 at a dosage of 25 µM vs 3.05 ± 1.24 in vehicle group, p < 0.001). Mechanism studies further suggested that procyanidin C1 activates the AKT-eNOS pathway, thus up-regulating glucose uptake and enhancing insulin sensitivity in mature adipocytes. Taken together, our study identified B-type procyanidin C1, a component of cinnamon extract, that stimulates preadipocyte differentiation and acts as a potential insulin action enhancer through the AKT-eNOS pathway in mature adipocytes.


Assuntos
Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Biflavonoides/farmacologia , Catequina/farmacologia , Cinnamomum zeylanicum/química , Insulina/metabolismo , Extratos Vegetais/farmacologia , Proantocianidinas/farmacologia , Células 3T3-L1 , Adipócitos/citologia , Animais , Transporte Biológico/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Glucose/metabolismo , Camundongos , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo
3.
J Cancer Res Clin Oncol ; 145(8): 1949-1976, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31292714

RESUMO

PURPOSE: Efflux transporters of the adenosine triphosphate-binding cassette (ABC)-superfamily play an important role in the development of multidrug resistance (multidrug resistant; MDR) in cancer. The overexpression of these transporters can directly contribute to the failure of chemotherapeutic drugs. Several in vitro and in vivo models exist to screen for the efficacy of chemotherapeutic drugs against MDR cancer, specifically facilitated by efflux transporters. RESULTS: This article reviews a range of efflux transporter-based MDR models used to test the efficacy of compounds to overcome MDR in cancer. These models are classified as either in vitro or in vivo and are further categorised as the most basic, conventional models or more complex and advanced systems. Each model's origin, advantages and limitations, as well as specific efflux transporter-based MDR applications are discussed. Accordingly, future modifications to existing models or new research approaches are suggested to develop prototypes that closely resemble the true nature of multidrug resistant cancer in the human body. CONCLUSIONS: It is evident from this review that a combination of both in vitro and in vivo preclinical models can provide a better understanding of cancer itself, than using a single model only. However, there is still a clear lack of progression of these models from basic research to high-throughput clinical practice.


Assuntos
Transportadores de Cassetes de Ligação de ATP/fisiologia , Antineoplásicos/isolamento & purificação , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Modelos Biológicos , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/genética , Antineoplásicos/farmacologia , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/genética , Técnicas de Cultura/métodos , Técnicas de Apoio para a Decisão , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistência a Múltiplos Medicamentos/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Especificidade de Órgãos , Seleção de Pacientes
4.
Life Sci ; 231: 116557, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31194994

RESUMO

AIMS: Vinegar-baked Radix Bupleuri (VBRB) potentiates the activity of anticancer drugs in the liver by increasing their hepatic distribution. However, this phenomenon may be associated with drug transporters. We investigated the effect of saikosaponin b2 (SSb2; the main component of VBRB) on the activity and expression of different drug transporters in both normal cells and those that overexpress the transporter. MAIN METHODS: The activities of transporters were analyzed by concentration of their cellular substrates. Concentrations of colchicine (substrate of Pgp and MRP1) and cisplatin (substrate of OCT2 and MRP2) were determined by high-performance liquid chromatography (HPLC). The concentration of rhodamine B was determined by flow cytometry. The expression of transporter gene and protein were determined by qRT-PCR and Western blotting analysis. KEY FINDINGS: SSb2 increased colchicine efflux in HEK293 cells by primarily increasing Mrp1 activity, independent of gene and protein expression. SSb2 enhanced Mrp2 function and increased cisplatin efflux in BRL3A cells by upregulating Mrp2 gene expression, with a marginal effect on Pgp in normal cells. SSb2 increased OCT2 activity in OCT2-HEK293 cells by increasing the expression of OCT2 protein and mRNA; however, SSb2 inhibited MRP2 activity in MRP2-HEK293 cells by decreasing MRP2 protein expression, and decreased Pgp and MRP1 activity in Pgp- and MRP1-HEK293 cells. SIGNIFICANCE: SSb2 might potentially be the key active component of VBRB that enhances the hepatotargeting of anticancer drugs through the inhibition of multidrug resistance-associated drug transporters (Pgp, MRP1, and MRP2) in an environment-dependent manner.


Assuntos
Proteínas Associadas à Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Ácido Oleanólico/análogos & derivados , Saponinas/metabolismo , Saponinas/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Antineoplásicos/farmacologia , Transporte Biológico/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Cisplatino/análise , Cisplatino/metabolismo , Cisplatino/farmacologia , Colchicina/análise , Colchicina/metabolismo , Colchicina/farmacologia , Resistência a Múltiplos Medicamentos/fisiologia , Células HEK293 , Humanos , Medicina Tradicional Chinesa , Proteínas de Membrana Transportadoras/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Ácido Oleanólico/metabolismo , Ácido Oleanólico/farmacologia , RNA Mensageiro/metabolismo , Rodaminas/análise , Rodaminas/metabolismo , Regulação para Cima/efeitos dos fármacos
5.
BMC Plant Biol ; 19(1): 283, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31248369

RESUMO

BACKGROUND: Metal homeostasis is critical for plant growth, development and adaptation to environmental stresses and largely governed by a variety of metal transporters. The plant ZIP (Zn-regulated transporter, Iron-regulated transporter-like Protein) family proteins belong to the integral membrane transporters responsible for uptake and allocation of essential and non-essential metals. However, whether the ZIP family members mediate metal efflux and its regulatory mechanism remains unknown. RESULTS: In this report, we provided evidence that OsZIP1 is a metal-detoxified transporter through preventing excess Zn, Cu and Cd accumulation in rice. OsZIP1 is abundantly expressed in roots throughout the life span and sufficiently induced by excess Zn, Cu and Cd but not by Mn and Fe at transcriptional and translational levels. Expression of OsZIP-GFP fusion in rice protoplasts and tobacco leaves shows that OsZIP1 resides in the endoplasmic reticulum (ER) and plasma membrane (PM). The yeast (Saccharomyces cerevisiae) complementation test shows that expression of OsZIP1 reduced Zn accumulation. Transgenic rice overexpressing OsZIP1 grew better under excess metal stress but accumulated less of the metals in plants. In contrast, both oszip1 mutant and RNA interference (RNAi) lines accumulated more metal in roots and contributed to metal sensitive phenotypes. These results suggest OsZIP1 is able to function as a metal exporter in rice when Zn, Cu and Cd are excess in environment. We further identified the DNA methylation of histone H3K9me2 of OsZIP1 and found that OsZIP1 locus, whose transcribed regions imbed a 242 bp sequence, is demethylated, suggesting that epigenetic modification is likely associated with OsZIP1 function under Cd stress. CONCLUSION: OsZIP1 is a transporter that is required for detoxification of excess Zn, Cu and Cd in rice.


Assuntos
Cádmio/metabolismo , Proteínas de Transporte de Cátions/genética , Cobre/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Oryza/genética , Proteínas de Plantas/genética , Zinco/metabolismo , Transporte Biológico/efeitos dos fármacos , Proteínas de Transporte de Cátions/química , Proteínas de Transporte de Cátions/metabolismo , Oryza/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Estresse Fisiológico
6.
J Agric Food Chem ; 67(25): 7157-7166, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31146527

RESUMO

Lonicera caerulea berry polyphenols (LCBP) are known to reduce cholesterol accumulation. Currently, it is unknown whether LCBP can activate Sirtuin 1 (SIRT1) to regulate the formation of RAW264.7 macrophage foam cells. In this study, the effect of LCBP on lipid accumulation in macrophages was evaluated. Fluorescently labeled ox-LDL and 25-NBD cholesterol were used to detect the ox-LDL uptake and cholesterol outflow rate from macrophages. Gene silencing was performed using siRNA to detect changes in the expression of the ATP-binding cassette transporter A1 (ABCA1), sterol regulatory element-binding protein 2 (SREBP2), and SIRT1 proteins using Western blotting, and changes in the expression of miR-33 were detected by real-time polymerase chain reaction. The results showed that treatment with 80 µg/mL LCBP significantly inhibited the accumulation of lipids in RAW264.7 macrophages induced by ox-LDL and reduced intracellular cholesterol levels by activating SIRT1 to enhance the expression of ABCA1, a cholesterol efflux gene, but not independent effect. Of the three key LCBP components investigated, chlorogenic acid was found to activate SIRT1 and regulate the expression of the cholesterol-related factors ABCA1, SREBP2, and miR-33; cyanidin-3-glucoside and catechins were effective to a lesser extent. Our results suggest a novel hypolipidemic mechanism of LCBP.


Assuntos
Colesterol/metabolismo , Células Espumosas/efeitos dos fármacos , Lonicera/química , Macrófagos/efeitos dos fármacos , Polifenóis/farmacologia , Sirtuína 1/metabolismo , Transportador 1 de Cassete de Ligação de ATP/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Células Espumosas/metabolismo , Frutas/química , Lipoproteínas LDL/metabolismo , Macrófagos/metabolismo , Camundongos , Células RAW 264.7 , Sirtuína 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo
7.
J Agric Food Chem ; 67(26): 7348-7364, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31180673

RESUMO

A chemical study on the peels of the cultivated edible mushroom Wolfiporia cocos led to the isolation and identification of 47 lanostane triterpenoids including 16 new compounds (1-16). The structures of the new compounds were determined by analysis of the NMR, MS, and electronic circular dichroism (ECD) data. Compounds 1 and 2 represent new members of the family of 4,5-secolanostane triterpenes. Compound 3 is a new aromatic lanostane triterpene with an unusual methyl rearrangement from C-10 to C-6. The absolute configurations of 1 and 8 were assigned by ECD spectra calculation. All compounds were evaluated for cytotoxicity (K562, SW480, and HepG2) and glucose-uptake-stimulating effects. Compounds 23, 25, 29, and 31 showed weak inhibition on the K562 cells with IC50 in the range of 25.7 to 68.2 µM, respectively. Compounds 21, 28, and 30 increased the glucose uptake in 3T3-L1 cells by 25%, 14%, and 50% at 5 µM, respectively. In addition, compounds 14, 23, 29, 35, and 43 showed insulin-sensitizing activity by increasing the insulin-stimulated glucose uptake at 2.5 µM in 3T3-L1 adipocytes. A preliminary structure-activity relationship analysis indicates that the 6/6/6/5 ring skeleton and the double bond between C-8 and C-9 are beneficial for the glucose-uptake-stimulating and insulin-sensitizing activities. Furthermore, the alkaline-insoluble fraction mainly containing compounds 22, 24, 28, and 31 were confirmed to have hypoglycemic and hypolipidemic activity on high-fat-diet-induced obese mice. This work confirms the potential of the peels' extracts of W. cocos as a functional food or dietary supplements.


Assuntos
Glucose/metabolismo , Extratos Vegetais/farmacologia , Triterpenos/farmacologia , Wolfiporia/química , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/farmacologia , Insulina/metabolismo , Camundongos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Triterpenos/química , Triterpenos/isolamento & purificação
8.
J Agric Food Chem ; 67(26): 7232-7242, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31184888

RESUMO

In the present study, the effect of imidacloprid uptake from contaminated soils on the growth of leaf vegetable Shanghaiqing was investigated. The result showed that during 35-day exposure, the concentration of imidacloprid (IMI) was in the order of vegetable shoots > vegetable roots > soil, indicating that IMI was more readily concentrated in vegetable shoots than in roots. Moreover, the biomass of IMI-treated vegetable shoots was comparable to that of the controls with early exposure, but was higher than that of the controls after 7-day exposure, showing that the test concentration of IMI could stimulate vegetable growth. The plant metabolic analysis of vegetable shoots using LC-QTOF/MS revealed that IMI may cause oxidative stress to the plant shoots with early exposure; however, the stressful situation of IMI seems to be relieved with the increase of some substances (such as spermidine and phenylalanine) with late exposure. Moreover, the upregulation of N-rich amino acids (glutamine, aspartate, and arginine) suggested that the process of fixing inorganic nitrogen in the plant should be enhanced, possibly contributing to enhanced growth rates. Additionally, four IMI's metabolites were identified by using MS-FINDER software, and the distribution of three metabolites in vegetable tissues was compared.


Assuntos
Inseticidas/farmacologia , Neonicotinoides/farmacologia , Nitrocompostos/farmacologia , Poluentes do Solo/farmacologia , Verduras/efeitos dos fármacos , Aminoácidos/metabolismo , Transporte Biológico/efeitos dos fármacos , Inseticidas/análise , Espectrometria de Massas , Neonicotinoides/análise , Nitrocompostos/análise , Estresse Oxidativo/efeitos dos fármacos , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/química , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Brotos de Planta/química , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Solo/química , Poluentes do Solo/análise , Verduras/química , Verduras/crescimento & desenvolvimento , Verduras/metabolismo
9.
J Microbiol Biotechnol ; 29(6): 973-983, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31216793

RESUMO

It is well known that iron is critical for bacterial growth and pathogenic virulence. Due to chemical similarity, Ga3+ competes with Fe3+ for binding to compounds that usually bind Fe3+, thereby interfering with various essential biological reactions. In our present study, gallium(III) nitrate [Ga(NO3)3] could repress the growth of V. splendidus Vs without complete inhibition. In the presence of Ga(NO3)3, the secretion of homogentisic acid-melanin (HGAmelanin) in V. splendidus Vs cells could be increased by 4.8-fold, compared to that in the absence of Ga(NO3)3. HGA-melanin possessed the ability to reduce Fe3+ to Fe2+. In addition, HGA-melanin increased the mRNA levels of feoA and feoB, genes coding Fe2+ transport system proteins to 1.86- and 6.1-fold, respectively, and promoted bacterial growth to 139.2%. Similarly, the mRNA expression of feoA and feoB was upregulated 4.11-fold and 2.71-fold in the presence of 640 µM Ga(NO3)3, respectively. In conclusion, our study suggested that although Ga(NO3)3 could interfere with the growth of V. splendidus Vs, it could also stimulate both the production of Fe3+-reducing HGA-melanin and the expression of feoA and feoB , which facilitate Fe2+ transport in V. splendidus Vs.


Assuntos
Gálio/farmacologia , Ferro/metabolismo , Vibrio/efeitos dos fármacos , Proteínas de Bactérias/genética , Transporte Biológico/efeitos dos fármacos , Proteínas de Transporte de Cátions/genética , Relação Dose-Resposta a Droga , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Ácido Homogentísico/química , Ácido Homogentísico/metabolismo , Ácido Homogentísico/farmacologia , Melaninas/química , Melaninas/metabolismo , Melaninas/farmacologia , Oxirredução , Sideróforos/metabolismo , Vibrio/crescimento & desenvolvimento , Vibrio/metabolismo
10.
Int J Nanomedicine ; 14: 3055-3067, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31118622

RESUMO

Purpose: The aim of this research was to develop a phospholipid complex based nanoemulsion system for oral insulin delivery. Methods: Insulin-phospholipid complex (IPC) was firstly prepared by an anhydrous co-solvent lyophilization method, and then encapsulated into the oil phase of nanoemulsion to obtain the IPC-based nanoemulsion (IPC-NE). Both water-in-oil (W/O) IPC-NE and oil-in-water (O/W) IPC-NE were formulated and evaluated for comparison. Results: The obtained W/O IPC-NE and O/W IPC-NE were both spherical in shape with a mean particle size of 18.6±0.79 nm and 27.3±1.25 nm, respectively. While both IPC-NEs exhibited enhanced Caco-2 cell monolayers permeability than IPC and insulin solution, W/O IPC-NE showed relatively greater protective effects against enzymatic degradation than O/W IPC-NE. Moreover, oral administration of W/O IPC-NE exhibited significant hypoglycemic effects, with 12.4-fold and 1.5-fold higher oral bioavailability compared with insulin solution and O/W IPC-NE, respectively. Conclusion: IPC-NEs, especially the W/O IPC-NE showed promising efficiency in vitro and in vivo, thus could be a potential strategy for oral insulin delivery.


Assuntos
Sistemas de Liberação de Medicamentos , Emulsões/química , Insulina/administração & dosagem , Nanopartículas/química , Fosfolipídeos/química , Administração Oral , Animais , Transporte Biológico/efeitos dos fármacos , Glicemia/metabolismo , Células CACO-2 , Morte Celular/efeitos dos fármacos , Portadores de Fármacos , Liberação Controlada de Fármacos , Emulsões/administração & dosagem , Humanos , Hipoglicemiantes/administração & dosagem , Insulina/farmacocinética , Insulina/farmacologia , Masculino , Nanopartículas/ultraestrutura , Tamanho da Partícula , Permeabilidade , Ratos Sprague-Dawley , Suínos , Difração de Raios X
11.
Environ Sci Pollut Res Int ; 26(20): 20475-20484, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31102230

RESUMO

The ambiguous mechanism that selenite seems to be absorbed by roots via phosphorus (P) and silicon (Si) transporters signifies P and Si may affect selenite uptake. However, the role of P and Si in phloem-mediated selenium (Se) transport within plant tissue is unknown. Therefore, in this work, tomato (Solanum lycopersicum L.) seedlings were exposed to selenite under different hydroponic conditions firstly. And then, split-root experiments were conducted. Results showed that Se uptake decreased as external pH increased. At pH 8, more selenite in the form of SeO32- was assimilated under P-deficient conditions than under P-normal conditions. Silicate inhibited Se uptake only at pH 3 (27.5% H2SeO3 +72.5% HSeO3-). The results of split-root experiments showed that Se concentrations in seedlings increased under heterogeneously high P or Si. Selenium transport from shoots to roots immersed in solution without selenite was also enhanced. This study illustrated that the affinity of tomato roots to assimilate selenite species followed the order of H2SeO3 >HSeO3- >SeO32-. H2SeO3 was absorbed into roots via Si transporters, whereas HSeO3- and a portion of SeO32- were absorbed via low- and high-affinity P transporters, respectively. In addition, heterogeneously high P or Si concentrations in environmental media could enhance phloem-mediated Se redistribution.


Assuntos
Lycopersicon esculentum/efeitos dos fármacos , Floema/metabolismo , Fosfatos/farmacologia , Ácido Selenioso/farmacocinética , Silicatos/farmacologia , Transporte Biológico/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Hidroponia , Lycopersicon esculentum/metabolismo , Floema/efeitos dos fármacos , Fósforo/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Plântula/efeitos dos fármacos , Selênio/metabolismo , Selênio/farmacocinética
12.
J Agric Food Chem ; 67(22): 6222-6231, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31117505

RESUMO

The anti-inflammatory effects and cellular transport mechanisms of all- E-astaxanthin and its 9Z- and 13Z-isomers were investigated in a Caco-2 cell monolayer model. All three astaxanthin isomers at 1.2 µM significantly reduced the TNF-α-induced secretion of IL-8 by 22-27%. Z-Astaxanthins, especially 9 Z-astaxanthin exhibited greater anti-inflammatory effect than all- E-astaxanthin by down-regulating pro-inflammatory cytokines COX-2 and TNF-α gene expression to 0.88 ± 0.01-fold and 0.83 ± 0.17-fold that of the negative control (NC), respectively. The anti-inflammatory effects of astaxanthin isomers were achieved via modulating the NF-κB signaling pathway as they down-regulated TNF-α-induced phosphorylation of IκBα from 5.3 ± 0.19-fold to 3.8 ± 0.33-4.5 ± 0.27-fold of NC. The scavenger receptor class B type I protein (SR-BI) was found to facilitate the cellular uptake of astaxanthin isomers. Its inhibitor (BLT-1) and antibody (Anti-SRBI) significantly reduced cellular uptake efficiency of all- E-astaxanthin (18.9% and 16.7%, respectively) and 13Z-astaxanthin (28.8% and 30.2%, respectively), but not of 9Z-astaxanthin. The molecular docking experiment showed that 13 Z-astaxanthin had significantly higher affinity with SR-BI (atomic contact energy: -420.31) than all- E-astaxanthin and 9 Z-astaxanthin, which at least partially supports the higher bioavailability of 13 Z-astaxanthin observed in vivo by others.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Receptores Depuradores Classe B/metabolismo , Transporte Biológico/efeitos dos fármacos , Células CACO-2 , Membrana Celular/efeitos dos fármacos , Membrana Celular/genética , Membrana Celular/metabolismo , Humanos , Interleucina-8/genética , Interleucina-8/metabolismo , Mucosa Intestinal/metabolismo , Isomerismo , Simulação de Acoplamento Molecular , NF-kappa B/metabolismo , Receptores Depuradores Classe B/genética , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Xantofilas/química , Xantofilas/metabolismo
13.
J Agric Food Chem ; 67(20): 5782-5791, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31055921

RESUMO

Reverse cholesterol transport (RCT) is a physiological process, in which excess peripheral cholesterol is transported to the liver and further excreted into the bile and then feces. Recently, fucoidans are reported to have a lipid-lowering effect. This study was designed to investigate whether fucoidan from the brown seaweed Ascophyllum nodosum lowers lipid by modulating RCT in C57BL/6J mice fed a high-fat diet. Our results indicated that fucoidan intervention significantly reduced plasma triglyceride, total cholesterol, and fat pad index and markedly increased high-density lipoprotein cholesterol in a dose-dependent manner. In the liver, fucoidan significantly increased the expression of peroxisome proliferator-activated receptor (PPAR)α, PPARγ, liver X receptor (LXR)ß, adenosine triphosphate (ATP) binding cassette (ABC)A1, ABCG8, low-density lipoprotein receptor (LDLR), scavenger receptor B type 1 (SR-B1), and cholesterol 7-α-hydroxylase A1 (CYP7A1) and decreased the triglyceride level and expression of proprotein convertase subtilisin/kexin type 9 (PCSK9) and PPARß but had no effect on LXRα, ABCG1, and ABCG5. In the small intestine, the fucoidan treatment significantly reduced the expression of Niemann-Pick C1-like 1 (NPC1L1) and improved ABCG5 and ABCG8. These results demonstrated that fucoidan can improve lipid transfer from plasma to the liver by activating SR-B1 and LDLR and inactivating PCSK9 and upregulate lipid metabolism by activating PPARα, LXRß, ABC transporters, and CYP7A1. In the small intestine, this fucoidan can decrease cholesterol absorption and increase cholesterol excretion by activating NPC1L1 and ABCG5 and ABCG8, respectively. In conclusion, fucoidan from A. nodosum may lower lipids by modulating RCT-related protein expression and can be explored as a potential compound for prevention or treatment of hyperlipidemia-related diseases.


Assuntos
Ascophyllum/química , Colesterol/metabolismo , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/administração & dosagem , Metabolismo dos Lipídeos/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Polissacarídeos/administração & dosagem , Alga Marinha/química , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Colesterol 7-alfa-Hidroxilase/genética , Colesterol 7-alfa-Hidroxilase/metabolismo , Dieta Hiperlipídica/efeitos adversos , Humanos , Hiperlipidemias/etiologia , Hiperlipidemias/genética , Hiperlipidemias/metabolismo , Receptores X do Fígado/genética , Receptores X do Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores de LDL/genética , Receptores de LDL/metabolismo , Receptores Depuradores/genética , Receptores Depuradores/metabolismo
14.
Plant Sci ; 283: 424-434, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31128714

RESUMO

Glutathione is a tripeptide involved in diverse aspects of plant metabolism. We investigated how the reduced form of glutathione, GSH, applied site-specifically to plants, affects zinc (Zn) distribution and behavior in oilseed rape plants (Brassica napus) cultured hydroponically. Foliar-applied GSH significantly increased the Zn content in shoots and the root-to-shoot Zn translocation ratio; furthermore, this treatment raised the Zn concentration in the cytosol of root cells and substantially enhanced Zn xylem loading. Notably, microarray analysis revealed that the gene encoding pectin methylesterase was upregulated in roots following foliar GSH treatment. We conclude that certain physiological signals triggered in response to foliar-applied GSH were transported via sieve tubes and functioned in root cells, which, in turn, increased Zn availability in roots by releasing Zn from their cell wall. Consequently, root-to-shoot translocation of Zn was activated and Zn accumulation in the shoot was markedly increased.


Assuntos
Brassica napus/efeitos dos fármacos , Glutationa/farmacologia , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Zinco/metabolismo , Transporte Biológico/efeitos dos fármacos , Brassica napus/metabolismo , Cromatografia Líquida de Alta Pressão , Análise de Sequência com Séries de Oligonucleotídeos , Floema/metabolismo , Folhas de Planta/metabolismo , Xilema/metabolismo
15.
Nature ; 569(7754): 141-145, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31019304

RESUMO

The serotonin transporter (SERT) regulates neurotransmitter homeostasis through the sodium- and chloride-dependent recycling of serotonin into presynaptic neurons1-3. Major depression and anxiety disorders are treated using selective serotonin reuptake inhibitors-small molecules that competitively block substrate binding and thereby prolong neurotransmitter action2,4. The dopamine and noradrenaline transporters, together with SERT, are members of the neurotransmitter sodium symporter (NSS) family. The transport activities of NSSs can be inhibited or modulated by cocaine and amphetamines2,3, and genetic variants of NSSs are associated with several neuropsychiatric disorders including attention deficit hyperactivity disorder, autism and bipolar disorder2,5. Studies of bacterial NSS homologues-including LeuT-have shown how their transmembrane helices (TMs) undergo conformational changes during the transport cycle, exposing a central binding site to either side of the membrane1,6-12. However, the conformational changes associated with transport in NSSs remain unknown. To elucidate structure-based mechanisms for transport in SERT we investigated its complexes with ibogaine, a hallucinogenic natural product with psychoactive and anti-addictive properties13,14. Notably, ibogaine is a non-competitive inhibitor of transport but displays competitive binding towards selective serotonin reuptake inhibitors15,16. Here we report cryo-electron microscopy structures of SERT-ibogaine complexes captured in outward-open, occluded and inward-open conformations. Ibogaine binds to the central binding site, and closure of the extracellular gate largely involves movements of TMs 1b and 6a. Opening of the intracellular gate involves a hinge-like movement of TM1a and the partial unwinding of TM5, which together create a permeation pathway that enables substrate and ion diffusion to the cytoplasm. These structures define the structural rearrangements that occur from the outward-open to inward-open conformations, and provide insight into the mechanism of neurotransmitter transport and ibogaine inhibition.


Assuntos
Microscopia Crioeletrônica , Ibogaína/química , Ibogaína/farmacologia , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/ultraestrutura , Inibidores de Captação de Serotonina/farmacologia , Serotonina/metabolismo , Sítios de Ligação/efeitos dos fármacos , Ligação Competitiva , Transporte Biológico/efeitos dos fármacos , Alucinógenos/química , Alucinógenos/farmacologia , Humanos , Modelos Moleculares , Conformação Proteica/efeitos dos fármacos , Proteínas da Membrana Plasmática de Transporte de Serotonina/química , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Inibidores de Captação de Serotonina/química , Relação Estrutura-Atividade
16.
Methods Mol Biol ; 1981: 87-98, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31016649

RESUMO

Drug-induced liver injury, and more specifically drug-induced cholestasis, is responsible for a large amount of hospitalizations and attrition of new drug candidates in preclinical drug development. Drug-induced cholestasis can be triggered by drugs that are inhibitors of the hepatic bile acid transporters. Therefore, it is of considerable interest in preclinical drug development to detect whether new candidate drugs can cause interference with the hepatic bile acid transporters. Although several cost-effective and fast in vitro assays are available to that end, these do not mimic the in vivo situation completely. In vivo research to monitor a new candidate drug's cholestatic potential is still relevant, yet is time-consuming and requires invasive sampling of a lot of laboratory animals. In this chapter, a protocol is provided to determine in vivo inhibition of the hepatic bile acid transporters in mice, using the nuclear imaging techniques positron emission tomography and single photon emission computed tomography. The protocol includes detailed information on preparation of the animal, scan acquisition, processing, and (statistical) analysis.


Assuntos
Ácidos e Sais Biliares/metabolismo , Ácidos e Sais Biliares/farmacologia , Animais , Transporte Biológico/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Colestase/metabolismo , Fígado , Camundongos , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada de Emissão de Fóton Único
17.
ACS Appl Mater Interfaces ; 11(18): 16905-16913, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-30993970

RESUMO

The physiochemical properties of nanoparticles (NPs), including surface charge, will affect their uptake, transformation, translocation, and final fate in the environment. In this study, we compared the phytoxoxicity and transport behaviors of nano CeO2 (nCeO2) functionalized with positively charged (Cs-nCeO2) and negatively charged (PAA-nCeO2) coatings. Cucumber seedlings were hydroponically exposed to 0-1000 mg/L of Cs-nCeO2 and PAA-nCeO2 for 14 days and the contents, distribution, translocation, and transformation of Ce in plants were analyzed using inductively coupled plasma mass spectrometry, micro X-ray fluorescence (µ-XRF), and X-ray absorption near-edge spectroscopy (XANES), respectively. Results showed that the seedling growth and Ce contents in plant tissues were functions of exposure concentrations and surface charge. Cs-nCeO2 was adsorbed strongly on a negatively charged root surface, which led to significantly higher Ce contents in the roots and lower translocation factors of Ce from the roots to shoots in Cs-nCeO2 group than in PAA-nCeO2 group. The results of µ-XRF showed that Ce elements were mainly accumulated at the root tips and lateral roots, as well as in the veins and at the edge of leaves. XANES results revealed that the proportion of Ce(III) was comparable in the plant tissues of the two groups. We speculated that Cs-nCeO2 and PAA-nCeO2 were partially dissolved under the effect of root exudates, releasing Ce3+ ions as a result. Then, the Ce3+ ions were transported upward in the form of Ce(III) complexes along the vascular bundles and eventually accumulated in the veins. The other portion of Cs-nCeO2 and PAA-nCeO2 entered the roots through the gap of a Casparian strip at root tips/lateral roots and was transported upward as intact NPs and finally accumulated at the edge of the blade. This study will greatly advance our information on how the properties of NPs influence their phytotoxicity, uptake, and subsequent trophic transfer in terrestrial food webs.


Assuntos
Cério/química , Cucumis sativus/efeitos dos fármacos , Nanopartículas/química , Plântula/efeitos dos fármacos , Transporte Biológico/efeitos dos fármacos , Cério/farmacologia , Cério/toxicidade , Cucumis sativus/crescimento & desenvolvimento , Cucumis sativus/ultraestrutura , Espectrometria de Massas , Nanopartículas/toxicidade , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/química , Raízes de Plantas/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/ultraestrutura , Espectroscopia por Absorção de Raios X
18.
Nutrients ; 11(4)2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30939853

RESUMO

Type 2 diabetes is a complex, heterogeneous, and polygenic disease. Currently, available drugs for treating type 2 diabetes predominantly include sulfonylureas, α-glucosidase inhibitors, and biguanides. However, long-term treatment with these therapeutic drugs is often accompanied by undesirable side effects, which have driven interest in the development of more effective and safer antidiabetic agents. To address the urgent need for new chemical solutions, we focused on the analysis of structurally novel and/or biologically new metabolites produced by insect-associated microbes as they have recently been recognized as a rich source of natural products. Comparative LC/MS-based analysis of Actinomadura sp. RB99, isolated from a fungus-growing termite, led to the identification of the type II polyketide synthase-derived fridamycin A. The structure of fridamycin A was confirmed by ¹H NMR data and LC/MS analysis. The natural microbial product, fridamycin A, was examined for its antidiabetic properties in 3T3-L1 adipocytes, which demonstrated that fridamycin A induced glucose uptake in 3T3-L1 cells by activating the AMP-activated protein kinase (AMPK) signaling pathway but did not affect adipocyte differentiation, suggesting that the glucose uptake took place through activation of the AMPK signaling pathway without inducing adipogenesis. Our results suggest that fridamycin A has potential to induce fewer side effects such as weight gain compared to rosiglitazone, a commonly used antidiabetic drug, and that fridamycin A could be a novel potential therapeutic candidate for the management of type 2 diabetes.


Assuntos
Adipócitos/efeitos dos fármacos , Glucose/metabolismo , Hipoglicemiantes/farmacologia , Células 3T3-L1 , Adipócitos/fisiologia , Adipogenia/efeitos dos fármacos , Animais , Transporte Biológico/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Hipoglicemiantes/química , Camundongos , Estrutura Molecular
19.
Phytomedicine ; 59: 152916, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30978651

RESUMO

BACKGROUND: Shengmai Formula (SMF) is widely used to treat cardiovascular disease such as chronic heart disease, coronary atherosclerotic heart disease, viral myocarditis, and others. Our previous studies have shown that OATP1B1/1B3 mediates the interactions between ophiopogon D and ginsenoside Rb1/Rd, which are the major active components in SMF. The herb-drug interactions that involve sodium taurocholate co-transporting polypeptide (NTCP) have been drawing increasing amounts of attention. PURPOSE: The aim of the present study was to investigate the interactions of the major effective components in SMF mediated by NTCP. METHODS: By using NTCP-overexpressing HEK293T cells and liquid chromatograph-mass spectrometer (LC-MS) analytical methods, we investigated the impact of the four main effective fractions and the 12 main effective components in SMF on NTCP-mediated sodium taurocholate (TCNa) uptake. The interactions of these effective components in SMF mediated by NTCP were further studied. RESULTS: The main effective fractions, ginseng total saponins (GTS), ophiopogon total saponins (OTS), ophiopogon total flavonoids (OTF), and fructus schisandrae total lignans (STL), all exhibited a certain inhibitory effect on the uptake of TCNa. Among the 12 main effective components, only ginsenoside Rg1, ophiopogon D', and schizandrin A showed inhibition of TCNa uptake, with IC50 values of 50.49 ± 4.24 µM, 6.71 ± 0.70 µM, and 45.80 ± 3.10 µM, respectively. Additionally, we found that ginsenoside Re and schizandrin B could be transported by NTCP-overexpressing HEK293T cells, and that the uptake of ginsenoside Re was significantly inhibited by OTS, OTF, STL, ginsenoside Rg1, ophiopogon D', and schizandrin A. The uptake of schizandrin B was significantly inhibited by GTS, OTS, OTF, and ophiopogon D'. CONCLUSION: Ginsenoside Rg1, ophiopogon D', and schizandrin A are potential inhibitors of NTCP and may interact with clinical drugs mediated by NTCP. Ginsenoside Re and schizandrin B are also potential substrates of NTCP, and their uptake mediated by NTCP was inhibited by the other components in SMF. The interaction of complex components based on NTCP may be one of the important compatibility mechanisms in SMF.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Transportadores de Ânions Orgânicos Dependentes de Sódio/metabolismo , Simportadores/metabolismo , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/fisiologia , Cromatografia Líquida , Células HEK293 , Humanos , Espectrometria de Massas
20.
Molecules ; 24(7)2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30959739

RESUMO

In recent studies, several alkaloids acting as cholinesterase inhibitors were isolated from Corydalis cava (Papaveraceae). Inhibitory activities of (+)-thalictricavine (1) and (+)-canadine (2) on human acetylcholinesterase (hAChE) and butyrylcholinesterase (hBChE) were evaluated with the Ellman's spectrophotometric method. Molecular modeling was used to inspect the binding mode of compounds into the active site pocket of hAChE. The possible permeability of 1 and 2 through the blood⁻brain barrier (BBB) was predicted by the parallel artificial permeation assay (PAMPA) and logBB calculation. In vitro, 1 and 2 were found to be selective hAChE inhibitors with IC50 values of 0.38 ± 0.05 µM and 0.70 ± 0.07 µM, respectively, but against hBChE were considered inactive (IC50 values > 100 µM). Furthermore, both alkaloids demonstrated a competitive-type pattern of hAChE inhibition and bind, most probably, in the same AChE sub-site as its substrate. In silico docking experiments allowed us to confirm their binding poses into the active center of hAChE. Based on the PAMPA and logBB calculation, 2 is potentially centrally active, but for 1 BBB crossing is limited. In conclusion, 1 and 2 appear as potential lead compounds for the treatment of Alzheimer's disease.


Assuntos
Acetilcolinesterase/efeitos dos fármacos , Alcaloides/química , Butirilcolinesterase/efeitos dos fármacos , Inibidores da Colinesterase/farmacologia , Acetilcolinesterase/química , Alcaloides/farmacologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/enzimologia , Berberina/análogos & derivados , Berberina/química , Berberina/farmacologia , Transporte Biológico/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Butirilcolinesterase/química , Inibidores da Colinesterase/química , Simulação por Computador , Corydalis/química , Dissacarídeos/química , Dissacarídeos/farmacologia , Humanos , Modelos Moleculares , Nitrocompostos/química , Nitrocompostos/farmacologia , Ligação Proteica/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA