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1.
J Cell Physiol ; 234(8): 13252-13262, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30580435

RESUMO

Although cardiac hypertrophy is widely recognized as a risk factor that leads to cardiac dysfunction and, ultimately, heart failure, the complex mechanisms underlying cardiac hypertrophy remain incompletely characterized. The nuclear receptor peroxisome proliferator-activated receptor δ (PPARδ) is involved in the regulation of cardiac lipid metabolism. Here, we describe a novel PPARδ-dependent molecular cascade involving microRNA-29a (miR-29a) and atrial natriuretic factor (ANF), which is reactivated in cardiac hypertrophy. In addition, we identify a novel role of miR-29a, in which it has a cardioprotective function in isoproterenol hydrochloride-induced cardiac hypertrophy by targeting PPARδ and downregulating ANF. Finally, we provide evidence that miR-29a reduces the isoproterenol hydrochloride-induced cardiac hypertrophy response, thereby underlining the potential clinical relevance of miR-29a in which it may serve as a potent therapeutic target for heart hypertrophy treatment.


Assuntos
Fator Natriurético Atrial/metabolismo , Cardiomegalia/metabolismo , Regulação da Expressão Gênica/fisiologia , MicroRNAs/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Regulação para Baixo , Camundongos , Camundongos Endogâmicos ICR , Miócitos Cardíacos/metabolismo
2.
Food Chem ; 208: 61-7, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27132824

RESUMO

Sweet potato (Ipomoea batatas) leaf (SPL) is an underused commercial vegetable with considerable bio-activities. By means of DPPH scavenging ability and α-glucosidase inhibitory oriented isolation, 9 and 7 compounds were isolated and identified, respectively. Among them, trans-N-(p-coumaroyl)tyramine (1), trans-N-feruloyltyramine (2), cis-N-feruloyltyramine (3), 4,5-feruloylcourmaoylquinic acid (8), caffeic acid ethyl ester (10), 7-hydroxy-5-methoxycoumarin (11), 7,3'-dimethylquercetin (13) and indole-3-carboxaldehyde (15), were firstly identified from SPL, and four of them (1, 2, 3 and 10) were firstly identified from genus Ipomoea. Phenethyl cinnamides and 3,4,5-triCQA exhibited the strongest α-glucosidase inhibition, while 3,4,5-triCQA and diCQAs were the dominant antioxidants. Structure-activity relationship revealed that higher caffeoylation of quinic acid and lower methoxylation of flavonols resulted in stronger antioxidant activity, and methylation and cis-configuration structure of phenethyl cinnamides weaken the α-glucosidase inhibition. Aforementioned results could help to explain the antioxidant activity and anti-diabetic activity of SPL, and provide theoretical basis for its further application.


Assuntos
Antioxidantes/análise , Inibidores de Glicosídeo Hidrolases/análise , Ipomoea batatas/química , Folhas de Planta/química , Bioensaio , Ácidos Cafeicos/análise , Ácidos Cumáricos/análise , Flavonóis/análise , Indóis/análise , Ácido Quínico/análise , Relação Estrutura-Atividade , Tiramina/análogos & derivados , Tiramina/análise , alfa-Glucosidases/análise
3.
Food Chem ; 186: 123-32, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25976801

RESUMO

This study aimed to evaluate the antioxidant potential of Artemisia selengensis Turcz (AST) leaves, a byproduct when processing AST stalk, and identify the antioxidant constituents by using HPLC-QTOF-MS(2). The total phenolics content (TPC), total flavonoids content (TFC) and antioxidant abilities of fractions resulted from the successively partition of chloroform, ethyl acetate and n-butanol were compared. Ethyl acetate fraction (EAF) exhibited the highest TFC (65.44 mg QuE/g fraction), n-butanol fraction (nBuF) showed the highest TPC (384.78 mg GAE/g fraction) and the best DPPH scavenging ability, ABTS(+) scavenging ability and reducing power. Totally, 57 compounds were identified or tentatively identified in nBuF and EAF, 40 of them were reported in AST for the first time. The major constituents in EAF were flavonoids, and the major constituents in nBuF were phenolic acids and organic acids. Thus, AST leaves might be a potential low-cost resource of natural antioxidants.


Assuntos
Antioxidantes/química , Artemisia/química , Extratos Vegetais/química , Antioxidantes/metabolismo , Artemisia/metabolismo , Flavonoides/química , Flavonoides/metabolismo , Metabolômica , Fenóis/química , Fenóis/metabolismo , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo
4.
Int J Biol Macromol ; 74: 103-10, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25475842

RESUMO

Dynamic high pressure microfluidization (DHPM)-assisted extraction (DHPMAE) of lotus (Nelumbo nucifera) leaves polysaccharides (LLPs) was optimized by response surface methodology. The optimal extraction conditions were: liquid/solid ratio of 35:1 (v/m, mL/g), processing pressure of 180 MPa, processed two times, extraction temperature of 76°C, extraction time of 50 min. Under the optimal extraction conditions, DHPMAE produced a higher polysaccharides yield (6.31%) than leaching (2.95%). Scanning electron microscope (SEM) analysis revealed that DHPM could reduce the particles size and make the surface more unconsolidated. The LLPs prepared by both methods showed similar FT-IR spectrum, and were consisted of the same monosaccharides, including rhamnose, fucose, arabinose, xylose, mannose, glucose and galactose. The content of each monosaccharide in extracts, however, was quite different. The average molecular weight of LLPs prepared by DHPMAE is 550 kDa, smaller than 578 kDa obtained by leaching. The LLPs prepared by DHPMAE exhibited stronger DPPH scavenging ability (IC50 value of 0.38 mg/mL), HO scavenging ability (IC50 value of 0.61 mg/mL) and reducing power. Therefore, DHPMAE can be a promising alternative to traditional extraction techniques for polysaccharides from plants, and lotus leaves might be a potential resource of natural antioxidants.


Assuntos
Nelumbo/química , Extratos Vegetais/química , Folhas de Planta/química , Polissacarídeos/química , Antioxidantes/química , Antioxidantes/farmacologia , Peso Molecular , Oxirredução/efeitos dos fármacos , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
5.
J Pharm Anal ; 4(6): 412-416, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29403908

RESUMO

A simple, fast and sensitive capillary electrophoresis (CE) strategy combined with chemiluminescence (CL) detection for analysis of ofloxacin (OF) enantiomers was established in the present work. Sulfonated ß-cyclodextrin (ß-CD) was used as the chiral additive being added into the running buffer of luminol-diperiodatocuprate (III) (K5[Cu(HIO6)2], DPC) chemiluminescence system. Under the optimum conditions, the proposed method was successfully applied to separation and analysis of OF enantiomers with the detection limits (S/N=3) of 8.0 nM and 7.0 nM for levofloxacin and dextrofloxacin, respectively. The linear ranges were both 0.010-100 µM. The method was utilized for analyzing OF in urine; the results obtained were satisfactory and recoveries were 89.5-110.8%, which demonstrated the reliability of this method. This approach can also be further extended to analyze different commercial OF medicines.

6.
Colloids Surf B Biointerfaces ; 84(1): 26-34, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21227659

RESUMO

Nanostructured biocomposite scaffolds of poly(l-lactide) (PLLA) blended with collagen (coll) or hydroxyapatite (HA), or both for tissue engineering application, were fabricated by electrospinning. The electrospun scaffolds were characterized for the morphology, chemical and tensile properties by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), water contact angle (WCA), Fourier transform infrared (FTIR) measurement, and tensile testing. Electrospun biocomposite scaffolds of PLLA and collagen or (and) HA in the diameter range of 200-700 nm mimic the nanoscale structure of the extracellular matrix (ECM) with a well-interconnection pore network structure. The presence of collagen in the scaffolds increased their hydrophility, and enhanced cell attachment and proliferation, while HA improved the tensile properties of the scaffolds. The biocompatibility of the electrospun scaffolds and the viability of contacting cells were evaluated by 4',6-diamidino-2-phenylindole dihydrochloride (DAPI) nuclear staining and by fluorescein diacetate (FDA) and propidium iodide (PI) double staining methods. The results support the conclusion that 293T cells grew well on composite scaffolds. Compared with pure PLLA scaffolds a greater density of viable cells was seen on the composites, especially the PLLA/HA/collagen scaffolds.


Assuntos
Colágeno/química , Durapatita/química , Nanoestruturas/química , Poliésteres/química , Adesão Celular , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Engenharia Tecidual
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(11): 1779-81, 2005 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-16499042

RESUMO

In an attempt to implement a novel type of immuno sensor based on IR spectroscopy, th e authorshave immobilized the herbicide atrazine on the surface of gold substrates. First, the authors synthesized a disulphide derivative of atrazine, then immobilized the herbicide atrazine on the surface of gold substrates by spontaneous chemisorption. The organic thin films were characterised by Fourier transform infrared reflection-absorption spectroscopy. A preliminary biological recognition experiment with an anti-ATZ antibody is promising.


Assuntos
Atrazina/análise , Ouro/química , Herbicidas/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral/métodos , Atrazina/química , Herbicidas/química , Estrutura Molecular
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