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1.
Phytochemistry ; 220: 114037, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38387725

RESUMO

Five undescribed bisabosqual-type meroterpenoids, bisabosquals E (1) and F (2), stachybisbins J-L (4-6), together with two known ones, were isolated from a novel endophytic fungus KMU22001 within the Stachybotryaceae family. Their structures with absolute configurations were elucidated by detailed interpretation of NMR spectroscopy, mass spectrometry, single-crystal X-ray diffraction and electronic circular dichroism calculations. Compounds 2, 4 and 6 exhibited significant cytotoxicities against five human cancer cell lines with IC50 values ranging from 1.80 ± 0.08 to 17.76 ± 0.97 µM.


Assuntos
Antineoplásicos , Delphinium , Humanos , Estrutura Molecular , Antineoplásicos/farmacologia , Cristalografia por Raios X , Dicroísmo Circular
2.
Sci Total Environ ; 918: 170637, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38316314

RESUMO

The Arctic Ocean, as a significant carbon sink, is attracting increased attention within the scientific community. This study focused on the main marginal sea ice zone, which has been the most sensitive to environmental changes in recent decades. Using data from reanalysis, models, and on-site observations, the changes in air-sea CO2 flux (FCO2) were analyzed during the influence of Arctic cyclones (ACs) in 2021-2022. Results indicated that the passage of ACs tended to increase the average carbon sink in the main marginal ice zone, with a more pronounced effect during the cold season. During ACs, the average FCO2 could reach -6.95 mmolC m-2 d-1. This was mainly associated with the stronger and more concentrated distribution of ACs where there was lower pCO2 (air-sea gradient of CO2 partial pressure) in the cold season. Additionally, the change in FCO2 during ACs was primarily affected by the sea surface wind and sea-ice concentration in the cold season, while it was influenced by a variety of environmental factors in the warm season, including the sea surface wind, sea-ice concentration, and ecological factors.

3.
Nat Prod Res ; 38(4): 581-588, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-36855227

RESUMO

The chemical epigenetic modifier 5-azacitidine (5-Aza C), a DNA methyltransferase inhibitor, was used to manipulate the endophytic fungus Penicillium sp. KMU18029. From its rice fermentation extract, a new polyketone compound (3S,4R)-3,4,8-trihydroxy-6-methyl-3,4-dihydronaphthalen-1(2H)-one (1), along with 13 known compounds, 3,4,8-trihydroxy-6-(hydroxymethyl)-3,4-dihydronaphthalen-1(2H)-one (2), decaturin B (3), 15-hydroxydecaturin A (4), oxalicine A (5), pileotin A (6), pyrandecarurin A (7), decaturenol A (8), decaturenoid (9), penisarins A (10), oxaline (11), (4E,8E)-N-D-2'-hydroxyocta-decanoyl-1-O-ß-D-glycopy-ranosyl-9-methyl-4,8-sphingadienine (12), ergosterol (13) and stigma-5-en-3-O-ß-glucoside (14), were separated. Among the known compounds, 2, 7, 12 and 14 were not found in our previous research on this strain. The structure of the new compound was identified by spectroscopic techniques such as HR-ESIMS, 1D NMR, 2D NMR and CD. Furthermore, all the isolated compounds were tested for their antimicrobial activities, and only compounds 1, 2 and 11 showed weak activities against S. aureus, with MICs of 128 µg/mL.


Assuntos
Azacitidina , Penicillium , Penicillium/química , Estrutura Molecular , Staphylococcus aureus , Espectroscopia de Ressonância Magnética , Epigênese Genética
4.
Fitoterapia ; 173: 105793, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38158161

RESUMO

Two novel fungal polyketides, phometides A (1) and B (2), together with four known compounds (3-6), were isolated from the endophytic fungus Phoma sp. YUD17001 obtained from Gastrodia elata Blume. The structures were elucidated based on spectroscopic analyses, X-ray crystal diffraction, and time-dependent density functional theory/electronic circular dichroism (TDDFT/ECD) calculations. Structurally, phometide A (1) represented the first example of C12 polyketide characterized by an unusual tetrahydrobenzofuran-3(2H)-one core with an α,ß-unsaturated ketone functionality, while phometide B (2) was an unprecedented molecule containing a 2-pentylcycloheptan-1-one scaffold. In an antimicrobial activity assay, phometide A (1) exhibited significant inhibitory activity against Staphylococcus aureus with MIC value of 4 µg/mL. Phometide B (2) showed moderate antifungal activity against Candida albicans with an MIC value of 16 µg/mL. Furthermore, compounds 1 and 2 were evaluated for their acetylcholinesterase inhibitory and cytotoxic activities.


Assuntos
Gastrodia , Policetídeos , Estrutura Molecular , Phoma , Acetilcolinesterase , Dicroísmo Circular
5.
Free Radic Biol Med ; 203: 24-33, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37023934

RESUMO

Mild inhibition of mitochondrial function leads to longevity. Genetic disruption of mitochondrial respiratory components either by mutation or RNAi greatly extends the lifespan in yeast, worms, and drosophila. This has given rise to the idea that pharmacologically inhibiting mitochondrial function would be a workable strategy for postponing aging. Toward this end, we used a transgenic worm strain that expresses the firefly luciferase enzyme widely to evaluate compounds by tracking real-time ATP levels. We identified chrysin and apigenin, which reduced ATP production and increased the lifespan of worms. Mechanistically, we discovered that chrysin and apigenin transiently inhibit mitochondrial respiration and induce an early ROS, and the lifespan-extending effect is dependent on transient ROS formation. We also show that AAK-2/AMPK, DAF-16/FOXO, and SKN-1/NRF-2 are required for chrysin or apigenin-mediated lifespan extension. Temporary increases in ROS levels trigger an adaptive response in a mitohormetic way, thereby increasing oxidative stress capacity and cellular metabolic adaptation, finally leading to longevity. Thus, chrysin and apigenin represent a class of compounds isolated from natural products that delay senescence and improve age-related diseases by inhibiting mitochondrial function and shed new light on the function of additional plant-derived polyphenols in enhancing health and delaying aging. Collectively, this work provides an avenue for pharmacological inhibition of mitochondrial function and the mechanism underlining their lifespan-extending properties.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/metabolismo , Longevidade/genética , Apigenina/farmacologia , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Mitocôndrias/metabolismo , Estresse Oxidativo , Trifosfato de Adenosina/metabolismo , Fatores de Transcrição Forkhead/genética
6.
Mech Ageing Dev ; 212: 111819, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37120065

RESUMO

Methods allowing light energy to be modulated in a controllable fashion are potentially important for finding the correlation between light-related environmental factors and aging-related lifespan. Here, we report photo- and thermo-regulation based on photonic crystals (PCs) for extended longevity of C. elegans. We show that PCs can function as a regulator of visible spectrum to tune photonic energy received by C.elegans. We provide direct evidence that lifespan depends on photonic energy, and the use of PCs reflecting blue light (440-537 nm) gives 8.3 % increasement in lifespan. We demonstrate that the exposure to modulated light alleviates photo-oxidative stress and unfolded-protein response. We realize reflective passive cooling temperature using PCs, and favorable low temperature could be created for worms to extend lifespan. This work offers a new path based on PCs to resist negative effects light and temperature for longevity, provides an available platform for studying the role of light in aging.


Assuntos
Proteínas de Caenorhabditis elegans , Longevidade , Animais , Longevidade/fisiologia , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Envelhecimento/fisiologia , Estresse Oxidativo/fisiologia
7.
Fitoterapia ; 166: 105443, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36736743

RESUMO

A new hybrid sorbicillinoid named paeciureallin (1) and a new monomeric sorbicillinoid named paecillyketide (2), along with six known analogues (3-8), were isolated from the rhizospheric soil-derived fungus Paecilomyces sp. KMU21009 associated with Delphinium yunnanense. Their structures were elucidated by extensive spectroscopic analysis and comparison with literature values. Paeciureallin (1) is the first example of hybrid sorbicillinoids possessing a rare sorbicillinoid urea unit and containing a ß-D-ribofuranose functionality. In pharmacological studies, compounds 1 and 2 were evaluated for in vitro anti-inflammatory and cytotoxic activities. Paeciureallin (1) exhibited moderate cytotoxicity against SW480 and A549 cell lines, and the IC50 values were 32.0 ± 0.1 and 34.4 ± 2.0 µM, respectively.


Assuntos
Antineoplásicos , Paecilomyces , Estrutura Molecular , Paecilomyces/química , Antineoplásicos/farmacologia , Anti-Inflamatórios
8.
J Nat Prod ; 85(6): 1486-1494, 2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35658485

RESUMO

Cultivation of an endophytic fungus Penicillium sp. KMU18029 with suberanilohydroxamic acid (SAHA), a histone deacetylase inhibitor, led to the isolation of two pairs of diterpenic meroterpenoids with a unique natural product framework combining features of pyripyropenes and decaturins/oxalicines, pyrandecarurins A (1) and B (2), pileotin A (3) and B (4), along with their potential precursor decaturenoid (5). Compounds 1, 2, 4, and 5 were new. The structures of 1-5 were elucidated by extensive spectroscopic analyses. The absolute configurations of 1-4 were determined by single-crystal X-ray diffraction, NOESY spectra, ECD calculations, and biogenetic considerations. The absolute configuration of compound 3 was confirmed for the first time. Compound 5 showed moderate activity against AChE with an IC50 value of 13.9 ± 1.1 µM.


Assuntos
Penicillium , Cristalografia por Raios X , Epigênese Genética , Inibidores de Histona Desacetilases , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Penicillium/química
9.
J Nat Prod ; 83(11): 3471-3475, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33180498

RESUMO

Penisarins A (1) and B (2), sesquiterpene coumarins with an unusual tricyclic sesquiterpene system, were isolated from endophytic Penicillium sp. KMU18029. Their structures were elucidated on the basis of spectroscopic methods, single-crystal X-ray diffraction, and electronic circular dichroism calculations. Compound 2 showed significant cytotoxicities against two human cancer cell lines, HL-60 and SMMC-7721, with IC50 values of 3.6 ± 0.2 and 3.7 ± 0.2 µM, respectively.


Assuntos
Cumarínicos/isolamento & purificação , Penicillium/química , Sesquiterpenos/isolamento & purificação , Linhagem Celular Tumoral , Dicroísmo Circular , Cumarínicos/química , Cristalografia por Raios X , Humanos , Estrutura Molecular , Sesquiterpenos/química
10.
J Environ Sci (China) ; 97: 45-53, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32933739

RESUMO

Estuarine wetland is the transitional interface linking terrestrial with marine ecosystems, and wetland microbes are crucial to the biogeochemical cycles of nutrients. The soil samples were collected in four seasons (spring, S1; summer, S2; autumn, S3; and winter, S4) from Suaeda wetland of Shuangtaizi River estuary, Northeast China, and the variations of bacterial community were evaluated by high-throughput sequencing. Soil properties presented a significant seasonal change, including pH, carbon (C) and total nitrogen (TN), and the microbial diversity, richness and structure also differed with seasons. Canonical correspondence analysis (CCA) and Mantel tests implied that soil pH, C and TN were the key factors structuring the microbial community. Gillisia (belonging to Bacteroidetes) and Woeseia (affiliating with Gammaproteobacteria) were the two primary components in the rhizosphere soils, displaying opposite variations with seasons. Based on PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) prediction, the xenobiotics biodegradation related genes exhibited a seasonal decline, while the majority of biomarker genes involved in nitrogen cycle showed an ascending trend. These findings could advance the understanding of rhizosphere microbiota of Suaeda in estuarine wetland.


Assuntos
Chenopodiaceae , China , Estuários , Filogenia , Rios , Estações do Ano , Solo , Microbiologia do Solo , Áreas Alagadas
11.
J Antibiot (Tokyo) ; 73(2): 77-81, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31636396

RESUMO

Two new azaphilone derivatives, comazaphilones G and H (1 and 2), together with eight known analogues (3-10), were isolated from an endophytic fungus Penicillium variabile. Their structures were established on the basis of extensive spectroscopic analysis. Compounds 1, 2 and 4-10 were tested their nitric oxide inhibitory activities in lipopolysaccharide-activated RAW 264.7 macrophage cells. Compounds 1, 2 and 4-9 showed significant nitric oxide inhibitory activities with IC50 values ranged from 4.35 ± 0.05 to 40.52 ± 0.47 µM.


Assuntos
Aconitum/microbiologia , Benzopiranos/isolamento & purificação , Óxido Nítrico/antagonistas & inibidores , Penicillium/química , Pigmentos Biológicos/isolamento & purificação , Animais , Benzopiranos/química , Benzopiranos/farmacologia , Endófitos/química , Concentração Inibidora 50 , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Pigmentos Biológicos/química , Pigmentos Biológicos/farmacologia , Raízes de Plantas , Células RAW 264.7
12.
Mar Pollut Bull ; 140: 171-178, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30803632

RESUMO

Microbial communities in wetland soils play vital roles in biogeochemical cycling of nutrients. In this study, the soil samples were collected from Suaeda, reed and Suaeda-reed hybrid zones in Shuangtaizi River Estuary, Northeast China, and the rhizosphere bacterial communities were compared using Illumina MiSeq sequencing. The microbial richness, diversity and structure of bacterial communities varied greatly in reed and Suaeda. Canonical correspondence analysis and Mantel test indicated that pH was the most significant factor (P < 0.05) in bacterial community assembly. Proteobacteria was the most dominant phylum, accounting for 45.7-58.0% of the total sequences. Thioprofundum, Thiohalomonas and Exiguobacterium were the predominant genera in Suaeda, while Exiguobacterium, Gillisia, Desulfomonile, Citrobacter, Thioprofundum and Acinetobacter were the core species in reed. PICRUSt analysis revealed similar functional profiles of rhizosphere microbiota in reed and Suaeda. Nitrate reduction related genes were abundant for nitrogen metabolism, whereas assimilatory sulfate reduction was the major process for sulfur metabolism.


Assuntos
Chenopodiaceae/microbiologia , Microbiota , Poaceae/microbiologia , Proteobactérias/isolamento & purificação , Rizosfera , Microbiologia do Solo , Áreas Alagadas , Chenopodiaceae/crescimento & desenvolvimento , China , Estuários , Poaceae/crescimento & desenvolvimento , Rios , Solo/química
13.
Mol Med Rep ; 15(4): 2353-2359, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28259947

RESUMO

Adipose and endothelial dysfunction is associated with cardiovascular disease. Perivascular adipose tissue (PVAT) directly surrounds vessels and influences vessel function via a paracrine effect, and adenosine monophosphate (AMP)-activated protein kinase (AMPK) modulates the metabolic pathway, thus, the present study hypothesized that activation of AMPK in PVAT may regulate endothelial function in pathological settings. The present study investigated the effect of methotrexate (MTX) on adipocytokine expression in PVAT with an emphasis on the regulation of endothelial function. The effects of MTX and the mechanisms involved were investigated using a relaxation assay and western blot analysis. Reverse transcription­quantitative polymerase chain reaction and western blotting were used to detect the mRNA and protein expression levels. ELISA assay was used to quantify the level of TNF­α and IL­6. Palmitic acid (PA) stimulation induced inflammation and dysregulation of adipocytokine expression in PVAT. MTX treatment inhibited nuclear factor­κB p65 phosphorylation and downregulated expression of pro­inflammatory cytokines, including tumor necrosis factor­α and interleukin-6, whereas adiponectin expression increased. MTX increased AMPK phosphorylation under basal and inflammatory conditions in PVAT, whereas knockdown of AMPK via small interfering RNA diminished its modulatory effect, indicating that MTX inhibits inflammation in an AMPK­dependent manner. The present study prepared conditioned medium from PA­stimulated PVAT to induce endothelial dysfunction and observed that pre­treatment of PVAT with MTX effectively restored the loss of acetylcholine­induced vasodilation and increased endothelial nitric oxide synthase phosphorylation in the rat aorta. The results of the present study demonstrated that MTX ameliorated inflammation-associated adipocytokine dysregulation and thus prevented endothelial dysfunction. These data provide further pharmacological evidence regarding the beneficial effects of MTX in cardiovascular diseases.


Assuntos
Proteínas Quinases Ativadas por AMP/imunologia , Tecido Adiposo/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Endotélio Vascular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Metotrexato/farmacologia , Óxido Nítrico Sintase Tipo III/imunologia , Transdução de Sinais/efeitos dos fármacos , Células 3T3-L1 , Tecido Adiposo/imunologia , Tecido Adiposo/patologia , Animais , Endotélio Vascular/imunologia , Endotélio Vascular/patologia , Inflamação/tratamento farmacológico , Inflamação/imunologia , Inflamação/patologia , Masculino , Camundongos , Ratos Sprague-Dawley , Vasodilatação/efeitos dos fármacos
14.
Int J Nanomedicine ; 11: 1067-76, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27042061

RESUMO

This study aimed to prepare the aminoclay-lipid hybrid composite to enhance the drug release and improve the oral bioavailability of poorly water-soluble fenofibrate. Antisolvent precipitation coupled with an immediate freeze-drying method was adopted to incorporate fenofibrate into aminoclay-lipid hybrid composite (ALC). The optimal composition of the ALC formulation was determined as the ratios of aminoclay to krill oil of 3:1 (w/w), krill oil to fenofibrate of 2:1 (w/w), and antisolvent to solvent of 6:4 (v/v). The morphological characteristics of ALC formulation were determined using scanning electron microscopy, differential scanning calorimetry, and X-ray powder diffraction, which indicated microcrystalline state of fenofibrate in ALC formulation. The ALC formulation achieved almost complete dissolution within 30 minutes, whereas the untreated powder and physical mixture exhibited less than 15% drug release. Furthermore, ALC formulation effectively increased the peak plasma concentration (C max) and area under the curve (AUC) of fenofibric acid (an active metabolite) in rats by approximately 13- and seven-fold, respectively. Furthermore, ALC formulation exhibited much lower moisture sorption behavior than the lyophilized formulation using sucrose as a cryoprotectant. Taken together, the present findings suggest that ALC formulation is promising for improving the oral absorption of poorly soluble fenofibrate.


Assuntos
Portadores de Fármacos/administração & dosagem , Fenofibrato/administração & dosagem , Fenofibrato/farmacocinética , Animais , Área Sob a Curva , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Liberação Controlada de Fármacos , Fenofibrato/análogos & derivados , Fenofibrato/sangue , Fenofibrato/química , Liofilização , Lipídeos/química , Masculino , Microscopia Eletrônica de Varredura , Nanopartículas/administração & dosagem , Nanopartículas/química , Ratos Sprague-Dawley , Solubilidade , Difração de Raios X
15.
Eur J Pharm Sci ; 78: 103-10, 2015 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-26165620

RESUMO

This research aimed to develop the omega-3 phospholipids based solid dispersion to improve the oral bioavailability of fenofibrate. The omega-3 phospholipids based solid dispersion formulation (OPSD) was prepared by an antisolvent precipitation with immediate freeze-drying and the optimal composition of the formulation was determined as the ratios of sucrose to krill oil of 5:1 (w/w), krill oil to fenofibrate of 1.5:1 (w/w), and antisolvent to solvent of 6:4 (v/v). The developed OPSD formulation was characterized by using scanning electron microscopy (SEM), X-ray powder diffraction (XRPD), and differential scanning calorimetry (DSC), which indicated the crystalline state of fenofibrate in the OPSD. The drug release profiles were also examined at different pHs. The OPSD achieved almost complete dissolution within 15 min, while the untreated powder and physical mixture exhibited minimal dissolution (less than 10% even after 2h). Furthermore, this formulation effectively increased the oral drug exposure in rats, as the Cmax and AUC of fenofibric acid (an active metabolite) were enhanced by approximately 6-7 folds. These results suggest that the OPSD formulation should be promising for improving the oral bioavailability of fenofibrate.


Assuntos
Ácidos Graxos Ômega-3 , Fenofibrato/análogos & derivados , Hipolipemiantes , Fosfolipídeos , Animais , Liberação Controlada de Fármacos , Ácidos Graxos Ômega-3/química , Ácidos Graxos Ômega-3/farmacocinética , Fenofibrato/química , Fenofibrato/farmacocinética , Hipolipemiantes/química , Hipolipemiantes/farmacocinética , Secreções Intestinais/química , Masculino , Fosfolipídeos/química , Fosfolipídeos/farmacocinética , Ratos Sprague-Dawley , Solubilidade
16.
Eur J Pharm Biopharm ; 89: 339-46, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25542680

RESUMO

This study aimed to design the chitosan coated TPGS liposome to enhance the bioavailability of Coenzyme Q10 (CoQ10). Optimization of formulation variables for the preparation of the liposome was performed and then three liposomal formulations (TPGS-liposome, TPGS-chitosome, chitosome) were prepared with narrow size distribution and high encapsulation efficiency. All of three liposomal formulations were stable at pH 1.2 and 7.0 for 24h without any significant drug leakage. Furthermore, chitosan-coated liposomes showed the strong mucoadhesive properties. All the tested liposomal formulations significantly enhanced the cellular uptake of CoQ10 as compared to the untreated drug. Particularly, TPGS-chitosome appeared to be most effective in improving the cellular uptake of CoQ10 in Caco-2 cells (about 30-folds greater than the untreated powder formulation). In oral pharmacokinetic studies, TPGS-chitosome enhanced the systemic exposure of CoQ10 by 3.4 folds as compared to the untreated powder and also displayed the extended drug release profile for up to 24h in rats. Compared to the untreated powder CoQ10, TPGS-chitosome significantly improved the antioxidant effect of CoQ10 and reduced the intracellular ROS level. In conclusion, TPGS-chitosome significantly enhanced the oral bioavailability of CoQ10 and prolonged drug release profile in rats, suggesting that TPGS-chitosome could be an effective oral delivery platform to improve the oral bioavailability of poorly absorbable drugs.


Assuntos
Quitosana/química , Lipossomos/química , Ubiquinona/análogos & derivados , Vitamina E/análogos & derivados , Administração Oral , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Disponibilidade Biológica , Células CACO-2 , Linhagem Celular Tumoral , Química Farmacêutica/métodos , Sistemas de Liberação de Medicamentos/métodos , Humanos , Masculino , Tamanho da Partícula , Polietilenoglicóis/química , Pós/química , Pós/metabolismo , Ratos , Ratos Sprague-Dawley , Ubiquinona/química , Ubiquinona/metabolismo , Vitamina E/química
17.
Arch Pharm Res ; 37(12): 1554-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25119994

RESUMO

The present study aimed to develop an effective oral formulation of tranilast (TL), a poorly soluble anti-inflammatory drug, via the formation of drug complex with 3-aminopropyl functionalized magnesium phyllosilicate (AMP clay) and improve the pH-dependent drug dissolution and bioavailability of TL. The drug-clay complex (TL-AMP complex) was prepared by co-precipitation method and its structural properties were characterized by X-ray powder diffraction, Fourier transform infrared spectroscopy and transmission electron microscopy. The dissolution profiles of TL-AMP complex were evaluated at different pHs. The formation of TL-AMP complex significantly improved the dissolution rate as well as the extent of drug release at acidic pHs, while the dissolution of untreated TL was negligible at pH 1.2 and 4.0. TL-AMP complex also achieved faster drug release than untreated drug (about 90 vs 30 % within 30 min) at pH 6.8. After oral administration to rats, TL-AMP complex enhanced significantly (p < 0.05) oral drug exposure and increased Cmax and AUC by six- and threefolds, respectively, compared to untreated TL. In conclusion, TL-AMP complex may be promising to improve the pH-dependent dissolution as well as bioavailability of TL.


Assuntos
Anti-Inflamatórios não Esteroides/química , Portadores de Fármacos/química , Silicatos de Magnésio/química , Silanos/química , ortoaminobenzoatos/química , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacocinética , Disponibilidade Biológica , Relação Dose-Resposta a Droga , Liberação Controlada de Fármacos , Masculino , Microscopia Eletrônica de Transmissão , Propilaminas , Ratos Sprague-Dawley , Solubilidade , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Fatores de Tempo , Difração de Raios X , ortoaminobenzoatos/administração & dosagem , ortoaminobenzoatos/farmacocinética
18.
Int J Pharm ; 471(1-2): 258-63, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-24834880

RESUMO

Telmisartan (TEL) belongs to BCS class II (low solubility/high permeability) and exhibits the pH-dependent drug release. Since 3-aminopropyl functionalized magnesium phyllosilicate (aminoclay) can intercalate or adsorb the negatively charged molecules via the electrostatic interaction, TEL-aminoclay complex was synthesized to improve the pH dependent drug release and the oral exposure of TEL. Co-precipitation method was adopted to incorporate TEL into aminoclay with the variation of drug/aminoclay ratios, and then dissolution profiles of TEL from TEL-aminoclay complex were evaluated at different pHs. Structural characterization was performed by XRD, ATR-FTIR, and TEM, indicating the electrostatic interaction between TEL and the surface of the aminoclay lamellae. Furthermore, drug crystallinity was changed to an amorphous form via the molecular interactions between TEL and aminoclay. TEL exhibited rapid and complete dissolution at pH 1.2 within 15 min from all the tested formulations. However, while the untreated powder indicated negligible dissolution at pH 4 and pH 6.8, the formation of drug-clay complex significantly improved the dissolution rate as well as the extent of drug release at the higher pHs. In addition, following an oral administration of TEL-aminoclay, Cmax and AUC of TEL increased by about 8 and 5 fold respectively, while Tmax was shorten. The results suggest that formation of aminoclay complex should be promising to enhance the bioavailability of a poorly soluble drug, TEL.


Assuntos
Benzimidazóis/administração & dosagem , Benzimidazóis/sangue , Benzoatos/administração & dosagem , Benzoatos/sangue , Portadores de Fármacos/química , Cloreto de Magnésio/química , Silanos/química , Administração Oral , Animais , Benzimidazóis/química , Benzoatos/química , Química Farmacêutica , Cromatografia Líquida de Alta Pressão , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Masculino , Propilaminas , Ratos Sprague-Dawley , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Telmisartan , Distribuição Tecidual
19.
J Mater Chem B ; 2(43): 7567-7574, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-32261894

RESUMO

3-Aminopropyl functionalized magnesium phyllosilicate (aminoclay) is a tailor-made organoclay material that has many biomedical applications. Defining the biodistribution and in vivo pharmacokinetics of aminoclay is essential to gauge the therapeutic potential of aminoclay. Therefore, the present study investigated the in vivo fate of aminoclay nanoparticles in a mouse model. Fluorescent Cy5.0-conjugated-aminoclay (Cy5.0-aminoclay) was synthesized for optical imaging and quantification in vivo and then its tissue distribution as well as elimination pathways was investigated in mice. After intravenous administration, fast tissue distribution of Cy5.0-aminoclay into various organs including the liver, kidney, lung, heart, and intestine was evident, as was the rapid clearance from each organ without any long-term accumulation. In addition, systemically administered nanoparticles were eliminated mainly from the urine and feces, where the nearly complete recovery of administered dose was achieved within 72 h. After oral administration, the biodistribution and pharmacokinetic studies indicated no intestinal absorption of Cy5.0-aminoclay. Consequently, about 90% of orally administered nanoparticles were eliminated via feces within 24 h. Taken all together, the present study highlights the low risk for long-term tissue accumulation of aminoclay particles, which may be desirable attributes for biomedical applications as a drug delivery carrier.

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