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1.
Molecules ; 26(20)2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34684890

RESUMO

In the fields of medicine and health, traditional high-performance liquid chromatography or UV-visible spectrophotometry is generally used for substance quantification. However, over time, nuclear magnetic resonance spectroscopy (NMR) has gradually become more mature. Nuclear magnetic resonance spectroscopy has certain advantages in the quantitative analysis of substances, such as being nondestructive, having a high flux and short analysis time. Nuclear magnetic resonance spectroscopy has been included in the pharmacopoeiae of various countries. In this paper, the principle of nuclear magnetic resonance spectroscopy and the recent progress in the quantitative study of natural products by NMR are reviewed, and its application in the quantitative study of natural products is proposed. At the same time, the problems of using NMR alone to quantify natural products are summarized and corresponding suggestions are put forward.


Assuntos
Produtos Biológicos/química , Cromatografia Líquida de Alta Pressão/métodos , Estudos de Avaliação como Assunto , Espectroscopia de Ressonância Magnética/métodos
2.
Molecules ; 26(6)2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33804799

RESUMO

Diffusion-ordered spectroscopy (DOSY) is a powerful tool for investigating mixtures and identifying peaks of chemical components. However, similar diffusion coefficients of the components, particularly for complex mixtures that contain crowded resonances, limit resolution and restrict application of the DOSY technique. In this paper, matrix-assisted DOSY were used to explore whether the diffusion resolution of a complex model involving indole alkaloid mixtures can be realized. Furthermore, we investigated the influence of different factors on the separation effect. The results showed that the changes in diffusion coefficient differences were achieved more obviously when using sodium dodecyl sulfate (SDS) micelles as the matrix. In addition, we also found that increasing the concentration of SDS can improve the resolution of the DOSY spectrum. Finally, after investigating the influence factors and NMR conditions, we demonstrated the applications of the SDS-assisted DOSY on analyzing the total alkaloid extract of Alstonia Mairei, and the virtual separation of mixtures was achieved.


Assuntos
Alcaloides Indólicos/química , Modelos Químicos , Dodecilsulfato de Sódio/química , Ressonância Magnética Nuclear Biomolecular
3.
J Am Chem Soc ; 143(10): 4017-4023, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33663217

RESUMO

Electrically activated soft actuators capable of large deformation are powerful and broadly applicable in multiple fields. However, designing soft actuators that can withstand a high strain, provide a large actuation displacement, and exhibit stable reversibility are still the main challenges toward their practical application. Here, for the first time, we report a two-dimensional (2D) conductive metal-organic framework (MOF) based electrochemical actuator, which consists of vertically oriented and hierarchical Ni-CAT NWAs/CNF electrodes through the use of a facile one-step in situ hydrothermal growth method. The soft actuator prepared in this study demonstrated improvements in actuation performance and benefits from both the intrinsically ordered porous architecture and efficient transfer pathways for fast ion and electron transport; furthermore, this actuator facilitated a considerably high diffusion rate and low interfacial resistance. In particular, the actuator demonstrated a rapid response (<19 s) at a 3 V DC input, large actuation displacement (12.1 mm), and a correspondingly high strain of 0.36% under a square-wave AC voltage of ±3 V. Specifically, the actuator achieved a broad-band frequency response (0.1-20 Hz) and long-term cyclability in air (10000 cycles) with a negligible degradation in actuation performance. Our work demonstrates new opportunities for bioinspired artificial actuators and overcomes current limitations in electrode materials for soft robotics and bionics.

4.
J Sep Sci ; 44(7): 1391-1403, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33470534

RESUMO

Rauvolfia vomitoria is widely distributed in the tropical regions of Africa and Asia, and has been used in traditional folk medicine in China. Indole alkaloids were found to be major bioactive components, while the effects of diabetes mellitus on the pharmacokinetic parameters of the components have not been reflected in vivo. In this study, an efficient and sensitive liquid chromatography-tandem mass spectrometry method was developed and validated for the simultaneous determination of five ingredients of R. vomitoria in rats. Detection was implemented in multiple-reaction-monitoring mode with an electrospray positive-ionization source. Validation parameters were all in accordance with the current criterion. The established method was effectively employed to compare the pharmacokinetic behaviors of five alkaloids (reserpine, yohimbine, ajmaline, ajmalicine, and serpentine) between normal and type 2 diabetic rats. The single-dose pharmacokinetic parameters of the five alkaloids were determined in normal and diabetic rats after oral administration of 100 and 200 mg/kg body weight. The results indicated that diabetes mellitus significantly altered the pharmacokinetic characteristics of yohimbine, ajmaline, and ajmalicine after oral administration in rats. This is an attempt to provide some evidence for clinicians that may serve as a guide for the use of antidiabetic medicine in clinical practice.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/farmacocinética , Alcaloides Indólicos/farmacocinética , Rauwolfia/química , Administração Oral , Animais , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/induzido quimicamente , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/sangue , Alcaloides Indólicos/administração & dosagem , Alcaloides Indólicos/sangue , Masculino , Estrutura Molecular , Plantas Medicinais/química , Ratos , Ratos Sprague-Dawley , Estreptozocina
5.
Planta Med ; 86(16): 1191-1203, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32668478

RESUMO

Physalis Calyx seu Fructus, a traditional Chinese medicine consisting of the calyxes and fruits of Physalis alkekengi var. franchetii, has been used as therapy for inflammation-related respiratory diseases such as excessive phlegm, cough, sore throat, and pharyngitis for a long history in China. The aim of the present study was to investigate the chemical constituents of Physalis Calyx seu Fructus and identify the bioactive constituents responsible for its traditional application as therapy for inflammation-related diseases. In the present study, one new phenylpropanoid (1: ), two new steroids (17: and 18: ), together with 55 known constituents have been purified from the EtOH extract of Physalis Calyx seu Fructus. Among them, seven and twelve known constituents were isolated for the first time from Physalis Calyx seu Fructus and the genus Physalis, respectively. Fourteen constituents, including steroids [physalins (5:  - 9, 12:  - 14: , and 15: ) and ergostane (21: )], a sesquiterpenoid (35: ), alkaloids (36: and 37: ), and a flavonoid (44: ), showed inhibitory effects against oxidative stress. Ten constituents, including steroids (5, 6, 8, 13: , and 15: ), sesquiterpenoids (34: and 35: ), alkaloids (37: and 41: ), and a flavonoid (43: ), were found be potential anti-inflammatory constituents of this medicinal plant. The inhibition of oxidative stress and inflammatory response may be related to the regulation of Nrf2 and nuclear factor-κB pathways. The ethnomedical use of Physalis Calyx seu Fructus as a treatment for respiratory diseases might be attributed to the combined inhibitory effects of steroids, alkaloids, sesquiterpenoids, and flavonoids against oxidative stress and inflammatory response.


Assuntos
Physalis , China , Flores , Frutas , Estresse Oxidativo
6.
Nat Prod Res ; : 1-5, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32722947

RESUMO

Two new triterpenoids, 3ß-hydroxytirucall-7,25-dien-24-one (1) and 3ß-acetoxytirucall-7,23,25-triene (2), along with one new sesquiterpenoid, alloaromadendrane-12α,14ß-dioic acid (3), were isolated from the vines and leaves of Chonemorpha megacalyx Pierre. Their structures were established on the basis of extensive spectroscopic data.

7.
Int J Biol Macromol ; 156: 471-484, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32243933

RESUMO

Glioblastoma (GBM) is the most malignant central nervous system tumor, with poor prognosis. Temozolomide (TMZ) has been used as a first-line drug for the treatment of GBM for over a decade, but its treatment benefits are limited by acquired resistance. Polysaccharides from Cibotium barometz (CBPs) are polysaccharides purified from the root of Cibotium barometz (L.) J. Sm., possessing sensitizing activity. The purpose of this study was to investigate the anti-cancer effect of CBP from different processing methods on U87 cells using a 1H NMR-based metabolic approach, complemented with qRT-PCR and flow cytometry, to identify potential markers and discover the targets to explore the underlying mechanism. Cibotium barometz is usually processed under sand heating in clinical applications. Polysaccharides from both the processed (PCBP) and raw (RCBP) C. barometz were prepared, and the effect on enhancing the sensitivity to TMZ was investigated in vitro. CBP can significantly increase the toxicity of TMZ to the U87 cell line, promote apoptosis, enhance cell cycle changes, and arrest cells in S phase, and RCBP demonstrated better activity. Multivariate statistical analyses, such as principal component analysis (PCA) and orthogonal projection to latent structure with discriminant analysis (OPLS-DA), were used to identify metabolic biomarkers, and 12 metabolites in the cell extract samples were clearly identified as altered after RCBP exposure. NMR-based cell metabolomics provided a holistic method for the identification of CBP's apoptosis-enhancing mechanisms and the exploration of its potential applications in preclinical and clinical studies.


Assuntos
Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polissacarídeos/química , Polissacarídeos/farmacologia , Temozolomida/química , Temozolomida/farmacologia , Traqueófitas/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Espectroscopia de Ressonância Magnética , Metaboloma , Metabolômica/métodos , Peso Molecular , Traqueófitas/metabolismo
8.
J Nat Prod ; 83(4): 1217-1228, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32159343

RESUMO

Environmental toxicant- and oxidant-induced [e.g., cigarette smoke (CS)] respiratory oxidative stress and inflammatory response play a vital role in the onset and progression of COPD. The nuclear factor erythroid 2-related factor 2 (Nrf2) represents an important mechanism for regulating intracellular oxidative stress and inflammatory response and is a promising target for developing agents against COPD. Herein, a bioactivity-guided purification of goldenberry (whole fruits of Physalis peruviana L.) led to the isolation of a novel and potent Nrf2 activator 4ß-hydroxywithanolide E (4ß-HWE). Our study indicated that (i) 4ß-HWE activated the Nrf2-mediated defensive response through interrupting Nrf2-Keap1 protein-protein interaction (PPI) via modification of Cys151 and Cys288 cysteine residues in Keap1 and accordingly suppressing the ubiquitination of Nrf2. (ii) 4ß-HWE enhanced intracellular antioxidant capacity and inhibited oxidative stress in normal human lung epithelial Beas-2B cells and wild-type AB zebrafish. (iii) 4ß-HWE blocked LPS-stimulated inflammatory response and inhibited LPS-stimulated NF-κB activation in RAW 264.7 murine macrophages. (iv) 4ß-HWE effectively suppressed oxidative stress and inflammatory response in a CS-induced mice model of pulmonary injury. Collectively, these results display the feasibility of using 4ß-HWE to prevent or alleviate the pathological progression of COPD and suggest that 4ß-HWE is a candidate or a leading molecule against COPD.


Assuntos
Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Pulmão/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Physalis/química , Vitanolídeos/farmacologia , Animais , Antioxidantes/farmacologia , Células Epiteliais/efeitos dos fármacos , Frutas , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/química , Camundongos , Estrutura Molecular , Fator 2 Relacionado a NF-E2/química , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fumaça , Tabaco , Vitanolídeos/química , Vitanolídeos/isolamento & purificação
9.
Free Radic Biol Med ; 152: 525-539, 2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-31760092

RESUMO

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease resulted from airflow obstructions, and there is a driving requirement for novel and effective preventive and therapeutic agents of COPD. Nuclear factor-erythroid 2-related factor 2 (Nrf2) has been regarded to be a promising therapeutic target for COPD. Resveratrol is a natural Nrf2 activator with antioxidant and anti-inflammatory properties, however, its application is limited by its relative low efficiency and poor bioavailability. Herein, based on the skeleton of resveratrol, trans-4,4'-dihydroxystilbene (DHS) has been firstly identified to be an Nrf2 activator, which is more potent than the well-known sulforaphane (SF) and resveratrol. Our results indicate that DHS blocks Nrf2 ubiquitylation through specifically reacting with Cys151 cysteine in Keap1 protein to activate Nrf2-regulated defensive response, and thus enhances intracellular antioxidant capability. Furthermore, DHS relieves lipopolysaccharide (LPS)-stimulated inflammatory response via inhibition of NF-κB. Importantly, DHS significantly ameliorates pathological alterations (e.g. infiltration of leukocytes and fibrosis), downregulates the levels of oxidant biomarkers malondialdehyde (MDA) and 8-oxo-7,8-dihydro-2'-deoxyguanosin (8-oxo-dG), and inhibits the overproductions of inflammatory mediators [e.g. tumor necrosis factor α (TNF-α), cyclooxygenase-2 (COX-2), and matrix metalloproteinase-9 (MMP-9)] in a cigarette smoke (CS)-induced pulmonary impairment mice model. Taken together, this study demonstrates that DHS attenuates the CS-induced pulmonary impairments through inhibitions of oxidative stress and inflammatory response targeting Nrf2 and NF-κB in vitro and in vivo, and could be developed into a preventive agent against pulmonary impairments induced by CS.


Assuntos
Fator 2 Relacionado a NF-E2 , Doença Pulmonar Obstrutiva Crônica , Animais , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Pulmão/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Fumar/efeitos adversos , Estilbenos
10.
Nat Prod Res ; 34(16): 2249-2254, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29553828

RESUMO

The enhanced osteoblast differentiation is beneficial to the prevention of osteoporosis. In this study, a homogeneous polysaccharide (LRP-S2A) with the potential of promoting osteoblast differentiation was obtained from the fruits of Lycium ruthenicum, a traditional herb for treatment of postmenopausal metabolic disorders. Structural identification indicated that LRP-S2A, with a relative molecular weight of 2.65 × 106 Da and an uronic acid content of 41.8%, contained Rha, Ara, Gal, Glc and GlcA in a molar ratio of 1.00 : 2.07 : 0.57 : 2.59 : 4.33 and was composed of a backbone consisting of 6-O-Me-α-(1→4)-D-GlcpA, 2-O-acetyl-α-(1→4)-D-Glcp, α-(1→2,4)-L-Rhap, ß-(1→3)-D-Galp andα-(1→3,5)-L-Araf, and some branches consisting of 6-O-Me-α-(1→4)-D-GlcpA and terminal α-L-Araf. These results suggested that LRP-S2A with the potential of promoting osteoblast differentiation was a new acidic polysaccharide.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Lycium/química , Osteoblastos/citologia , Polissacarídeos/química , Animais , Células Cultivadas , Frutas/química , Humanos , Peso Molecular , Polissacarídeos/farmacologia , Ácidos Urônicos/análise
11.
Zhongguo Zhong Yao Za Zhi ; 44(22): 4918-4923, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31872601

RESUMO

Ultra performance liquid chromatography-tandem mass spectrometry( UPLC-MS/MS) was used to establish the simultaneous determination method of eight neurotransmitters in brain,liver,kidney,adrenal gland,serum and urine,including serotonin,5-hydroxyindole acetic acid,epinephrine,norepinephrine,dopamine,glutamic acid,γ-aminobutyric acid,and acetylcholine,and then investigate the distribution characteristics of neurotransmitters in rat tissues,blood and urine. Waters ACQUITY UPLC BEH C_(18) column( 2. 1 mm×100 mm,1. 7 µm) was used,with 0. 3% formic acid solution-acetonitrile as the mobile phase for gradient elution.Multiple reaction monitoring( MRM) scanning method under positive mode by atmospheric pressure electrospray ion source( ESI) was also performed to establish the detection method of neurotransmitters for methodological research. The plasma,urine and tissues of normal rats were pre-treated including homogenization,centrifuging,and protein removal,then the 2 µL supernatant was injected for analysis. The results showed that eight kinds of neurotransmitters could be accurately determined within 7 min,with linear correlation coefficients all greater than 0. 99. This method showed high accuracy and good precision,with specificity,stability,extraction recovery and matrix effects all complying with the biological sample analysis requirements. The most abundant transmitters in the brain,liver,kidney,kidney gland,blood and urine were γ-aminobutyric acid,glutamic acid,glutamic acid,adrenaline,glutamic acid and dopamine.The method is sensitive,rapid,precise,accurate and specific,and can be used for simultaneous quantitative analysis of eight neurotransmitters in biological samples. The investigation of the distribution ratio of transmitters in rats is of important significance to disease prevention and treatment.


Assuntos
Neurotransmissores/metabolismo , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Neurotransmissores/sangue , Neurotransmissores/urina , Ratos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Angew Chem Int Ed Engl ; 58(43): 15362-15366, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31441563

RESUMO

The electrochemical nitrogen reduction reaction (NRR) offers an energy-saving and environmentally friendly approach to produce ammonia under ambient conditions. However, traditional catalysts have extremely poor NRR performances because of their low activity and the competitive hydrogen evolution reaction. The high catalytic activity of nanoporous gold (NPG) and the hydrophobicity and molecular concentrating effect of the zeolitic imidazolate framework-8 (ZIF-8) were incorporated in the NPG@ZIF-8 nanocomposite so that the ZIF-8 shell could weaken hydrogen evolution and retard reactant diffusion. A highest Faradaic efficiency of 44 % and an excellent rate of ammonia production of (28.7±0.9) µg h-1 cm-2 were achieved, which are superior to traditional gold nanoparticles and NPG. Moreover, the composite catalyst shows high electrochemical stability and selectivity (98 %). The superior NRR performance makes NPG@ZIF-8 one of the most promising water-based NRR electrocatalysts for ammonia production.

13.
Spectrochim Acta A Mol Biomol Spectrosc ; 222: 117158, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31181505

RESUMO

Artemisinin-based combination therapy is widely used for the treatment of uncomplicated Plasmodium falciparum malaria, and piperaquine (PQ) is one of the important partner drugs. During the biotransformation of PQ, M1 (N-oxidation product), M2 (N-oxidation product), M3 (carboxylic acid product), M4 (N-dealkylation product), and M5 (N-oxidated product of M4) are formed by cytochrome P450 pathways. Despite decades of clinical use, the interactions between PQ and its main metabolites (PQs) with human serum albumin (HSA) have not been reported. In the present study, the binding of PQs with HSA under physiological conditions was investigated systematically through fluorescence, circular dichroism (CD) spectroscopy, and molecular docking methods. The experimental results show that the intrinsic fluorescence quenching of HSA was induced by those compounds resulting from the formation of stable HSA-compound complexes. The main forces involved in the interactions between PQ, M1, and M2 which bind to HSA were hydrogen s and van der Waals forces, while the interactions of M3, M4, and M5 were driven by hydrophobic forces. The main binding sites of the compounds to HSA were also examined by classical fluorescent marker experiments and molecular docking studies. Binding constants (Kb) revealed that the affinities of the PQ, M1, M2, M3, and M4 to HSA were stronger than that of M5. Additionally, the binding rates of PQs with HSA were determined by ultrafiltration methods. Consistent with the binding constant results, the binding rate of M5 was lower than the binding rates of PQ, M1, M2, M3, and M4. Furthermore, PQs binding to HSA led to conformational and structural alterations of HSA, as revealed by multi-spectroscopic studies. In order to investigate one possible mechanism by which PQs inhibit the growth of malaria-causing Plasmodium parasites, 1H NMR spectroscopy was performed to investigate the interaction of the PQs with heme. This study is beneficial to enhance our understanding of the ecotoxicology and environmental behaviors of PQ and its metabolites.


Assuntos
Antimaláricos/metabolismo , Quinolinas/metabolismo , Albumina Sérica Humana/metabolismo , Antimaláricos/química , Sítios de Ligação , Dicroísmo Circular , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Espectroscopia de Prótons por Ressonância Magnética , Quinolinas/química , Albumina Sérica Humana/química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Termodinâmica
14.
Mar Biotechnol (NY) ; 21(4): 475-487, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31020472

RESUMO

Post-transcriptional regulatory mechanisms play important roles in the regulation of LC-PUFA biosynthesis. Our previous study revealed that miR-33 could increase the expression of fatty acyl desaturases (fads2) in the rabbitfish Siganus canaliculatus, but the specific mechanism is unknown. Here, we confirmed that miR-33 could target the 3'UTR of insulin-induced gene 1 (insig1), resulting in downregulation of its protein level in the rabbitfish hepatocyte line (SCHL). In vitro overexpression of miR-33 inhibited the mRNA level of insig1 and increased the mRNA levels of Δ6Δ5 fads2 and elovl5, as well as srebp1. In SCHL cells, proteolytic activation of sterol-regulatory-element-binding protein-1 (Srebp1) was blocked by Insig1, with overexpression of insig1 decreasing mature Srebp1 level, while inhibition of insig1 led to the opposite effect. Srebp1 could enhance the promoter activity of Δ6Δ5 fads2 and elovl5, whose expression levels decreased with knockdown of srebp1 in SCHL. Overexpression of miR-33 also resulted in a higher conversion of 18:3n-3 to 18:4n-3 and 20:5n-3 to 22:5n-3, linked to desaturation and elongation via Δ6Δ5 Fads2 and Elovl5, respectively. The results suggested that the mechanism by which miR-33 regulates LC-PUFA biosynthesis in rabbitfish is through enhancing the expression of srebp1 by targeting insig1. The findings here provide more insight to the mechanism of miRNAs involvement in the regulation of LC-PUFA biosynthesis in teleosts.


Assuntos
Ácidos Graxos Dessaturases/genética , Ácidos Graxos Insaturados/biossíntese , Proteínas de Peixes/genética , MicroRNAs/genética , Perciformes/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Regiões 3' não Traduzidas , Animais , Linhagem Celular , Clonagem Molecular , Ácidos Graxos Dessaturases/metabolismo , Proteínas de Peixes/metabolismo , Expressão Gênica , Regulação da Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Células HEK293 , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Metabolismo dos Lipídeos/genética , MicroRNAs/metabolismo , Perciformes/metabolismo , Regiões Promotoras Genéticas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
15.
Free Radic Res ; 53(3): 348-358, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30773942

RESUMO

The nuclear factor erythroid 2-related factor 2 (Nrf2) plays a crucial role in regulating the intracellular oxidative stress, and thus activation of Nrf2 by nature-derived molecules effectively alleviates the pathological process of oxidative stress-induced chronic diseases. The isopentenyl-substituted flavonoid norartocarpin (NOR) induced the activity of NAD(P)H: quinone reductase (QR), implying that it might be a potential Nrf2 activator. Further studies indicated that NOR upregulated the protein levels of Nrf2 and its downstream genes, NAD(P)H quinone oxidoreductase 1 (NQO1), and γ-glutamyl cysteine synthetase (GCLM) through facilitating the nuclear translocation of Nrf2 and enhancing Nrf2 protein stability. NOR-induced activation of Nrf2 pathway was associated with multiple upstream kinases, including mitogen-activated protein kinase (MAPK), phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K), protein kinase C (PKC), and protein kinase R-like endoplasmic reticulum kinase (PERK). Moreover, NOR protected human lung epithelial Beas-2B cells against sodium arsenite [As(III)]-induced cytotoxicity in an Nrf2-dependent manner. Collectively, NOR was firstly identified to be an Nrf2 activator, which demonstrated the capability of preventing oxidative insults in human lung epithelial cells.


Assuntos
Células Epiteliais/metabolismo , Flavonoides/uso terapêutico , Pulmão/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Flavonoides/farmacologia , Humanos , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais
16.
Inorg Chem ; 57(24): 15062-15068, 2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30346740

RESUMO

The first double-walled bimetal-organic framework [Cd4K4(TADA)4(H2O)12]·6DMF (1, TADA = 3,3'-((6-hydroxy-1,3,5-triazine-2,4-diyl)bis(azanediyl)) dibenzoate) has been successfully constructed. In virtue of its high porosity and abundant basic sites, MOF 1 can be served as a high-efficiently size-selective heterogeneous catalyst for Knovenagel condensation reaction. Remarkably, 1 also exhibits excellent luminescent detectability for metronidazole (MDZ) with the highest quenching constant ( Ksv) of 1.16 × 105 M-1. The results demonstrate that 1 can be served as a unique bifunctional platform for antibiotics sensing and size-selective catalysis.


Assuntos
Antibacterianos/análise , Antibacterianos/química , Estruturas Metalorgânicas/química , Antibacterianos/síntese química , Catálise , Cristalografia por Raios X , Luminescência , Estruturas Metalorgânicas/síntese química , Modelos Moleculares , Tamanho da Partícula , Propriedades de Superfície
17.
Oxid Med Cell Longev ; 2018: 7616852, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29743984

RESUMO

Oxidative stress and inflammation undoubtedly contribute to the pathogenesis of many human diseases. The nuclear transcription factor erythroid 2-related factor (Nrf2) and the nuclear factor κB (NF-κB) play central roles in regulation of oxidative stress and inflammation and thus are targets for developing agents against oxidative stress- and inflammation-related diseases. Our previous study indicated that the EtOH extract of Litsea garrettii protected human bronchial epithelial cells against oxidative insult via the activation of Nrf2. In the present study, a systemic phytochemical investigation of L. garrettii led to the isolation of twenty-one chemical ingredients, which were further evaluated for their inhibitions on oxidative stress and inflammation using NAD(P)H:quinone reductase (QR) assay and nitric oxide (NO) production assay. Of these ingredients, 3-methoxy-5-pentyl-phenol (MPP, 5) was identified as an Nrf2 activator and an NF-κB inhibitor. Further studies demonstrated the following: (i) MPP upregulated the protein levels of Nrf2, NAD(P)H:quinone oxidoreductase 1 (NQO1), and glutamate-cysteine ligase regulatory subunit (GCLM); enhanced the nuclear translocation and stabilization of Nrf2; and inhibited arsenic [As(III)]-induced oxidative insult in normal human lung epithelial Beas-2B cells. And (ii) MPP suppressed the nuclear translocation of NF-κB p65 subunit; inhibited the lipopolysaccharide- (LPS-) stimulated increases of NF-κB p65 subunit, COX-2, iNOS, TNF-α, and IL-1ß; and blocked the LPS-induced biodegrade of IκB-α in RAW 264.7 murine macrophages. Taken together, MPP displayed potential preventive effects against inflammation- and oxidative stress-related diseases.


Assuntos
Anti-Inflamatórios/uso terapêutico , Brônquios/patologia , Células Epiteliais/efeitos dos fármacos , Inflamação/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Fenóis/uso terapêutico , Extratos Vegetais/uso terapêutico , Animais , Anti-Inflamatórios/química , Células Epiteliais/fisiologia , Etanol/química , Regulação da Expressão Gênica , Humanos , Interleucina-1beta/metabolismo , Litsea/imunologia , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Fenóis/química , Extratos Vegetais/química , Quinona Redutases/metabolismo , Células RAW 264.7 , Fator de Necrose Tumoral alfa/metabolismo
18.
Dev Comp Immunol ; 67: 361-376, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27581742

RESUMO

Tumor necrosis factor receptor-associated factor 6 (TRAF6) is a key cytoplasm signal adaptor that mediates signals activated by tumor necrosis factor receptor (TNFR) superfamily and the Interleukin-1 receptor/Toll-like receptor (IL-1/TLR) superfamily. The full-length 2492 bp TRAF6 (Sp-TRAF6) from Scylla paramamosain contains 1800 bp of open reading frame (ORF) encoding 598 amino acids, including an N-terminal RING-type zinc finger, two TRAF-type zinc fingers and a conserved C-terminal meprin and TRAF homology (MATH) domain. Multiple alignment analysis shows that the putative amino acid sequence of Sp-TRAf6 has highest identity of 88% with Pt-TRAF6 from Portunus trituberculatus, while the similarity of Sp-TRAF6 with other crustacean sequences was 54-55%. RT-PCR analysis indicated that Sp-TRAF6 transcripts were predominantly expressed in the hepatopancreas and stomach, whereas it was barely detected in the heart and hemocytes in our study. Moreover, Sp-TRAF6 transcripts were significantly up-regulated after Vibrio parahemolyticus and LPS challenges. RNA interference assay was carried out used by siRNA to investigate the genes expression patterns regulated by Sp-TRAF6. The qRT-PCR results showed that silencing Sp-TRAF6 gene could inhibit SpALF1, SpALF2, SpALF5 and SpALF6 expression in hemocytes, while inhibit SpALF1, SpALF3, SpALF4, SpALF5 and SpALF6 expression in hepatopancreas. Taken together, the acute-phase response to immune challenges and the inhibition of SpALFs gene expression indicate that Sp-TRAF6 plays an important role in host defense against pathogen invasions via regulation of ALF gene expression in S. paramamosain.


Assuntos
Proteínas de Artrópodes/metabolismo , Braquiúros/imunologia , Hepatopâncreas/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Vibrioses/imunologia , Vibrio parahaemolyticus/imunologia , Animais , Proteínas de Artrópodes/genética , Células Cultivadas , Clonagem Molecular , Regulação da Expressão Gênica , Imunidade Inata , Lipopolissacarídeos/imunologia , Filogenia , RNA Interferente Pequeno/genética , Alinhamento de Sequência , Transdução de Sinais , Fator 6 Associado a Receptor de TNF/genética , Receptores Toll-Like/metabolismo , Transcriptoma
19.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(3): 1587-8, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-25208182

RESUMO

In this study, we report the complete mitochondrial genome sequence of David's myotis, Myotis davidii. The genome is found to be 17,531 bp in length and has a base composition of A (33.8%), G (13.2%), C (23.2%), and T (29.8%). Similar to other bats, it contains a typically conserved structure including 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and 1 control region (D-loop). Most of the genes are encoded on H-strand, except for the ND6 subunit gene and 8 tRNA genes. All protein-coding genes start with an ATG codon except for ND2, ND3 and ND5, which initiate with ATT or ATA instead, and terminate with the typical stop codon (TAA/TAG) or a single T (T-) or an unexpected codon of AGA. The complete mitochondrial genome sequence provided here would be useful for further phylogenetic analysis and population genetic studies in M. davidii.


Assuntos
Quirópteros/genética , Genoma Mitocondrial , Animais , Composição de Bases , Códon de Iniciação , Códon de Terminação , DNA Mitocondrial/química , DNA Mitocondrial/isolamento & purificação , DNA Mitocondrial/metabolismo , Fases de Leitura Aberta/genética , RNA Ribossômico/química , RNA Ribossômico/isolamento & purificação , RNA Ribossômico/metabolismo , RNA de Transferência/química , RNA de Transferência/isolamento & purificação , RNA de Transferência/metabolismo , Análise de Sequência de DNA
20.
Artigo em Inglês | MEDLINE | ID: mdl-25103443

RESUMO

In this study, we report the complete mitochondrial genome sequence of brandt's bat, Myotis brandtii. The genome is found to be 17,470 bp in length and has a base composition of A (33.1%), G (13.6%), C (24.6%), and T (28.6%). Similar to other bats, it contains a typically conserved structure including 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and 1 control region (D-loop). Most of the genes are encoded on H-strand, except for the eight tRNA and ND6 genes. All protein-coding genes start with an ATG codon except for ND2, ND3 and ND5, which initiate with ATC or ATA instead, and terminate with the typical stop codon (TAA/TAG) or a single T (T- -) or an unexpected codon of AGA. The complete mitochondrial genome sequence provided here would be useful for further phylogenetic analysis and population genetic studies in M. brandtii.


Assuntos
Quirópteros/genética , Genoma Mitocondrial , Mitocôndrias/genética , Animais , Composição de Bases , Ordem dos Genes , Tamanho do Genoma , Análise de Sequência de DNA/métodos
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