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1.
Phytomedicine ; 123: 155223, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38134862

RESUMO

BACKGROUND AND AIMS: Crohn's disease (CD) is characterized by an overabundance of epithelial cell death and an imbalance in microflora, both of which contribute to the dysfunction of the intestinal barrier. Arjunolic acid (AA) has anti-apoptotic effects and regulates microbiota efficacy. The objective of this study was to assess the impact of the treatment on colitis resembling Crohn's disease, along with exploring the potential underlying mechanism. METHODS: CD animal models were created using Il-10-/- mice, and the impact of AA on colitis in mice was evaluated through disease activity index, weight fluctuations, pathological examination, and assessment of intestinal barrier function. To clarify the direct role of AA on intestinal epithelial cell apoptosis, organoids were induced by LPS, and TUNEL staining was performed. To investigate the potential mechanisms of AA in protecting the intestinal barrier, various methods including bioinformatics analysis and FMT experiments were employed. RESULTS: The treatment for AA enhanced the condition of colitis and the function of the intestinal barrier in Il-10-/- mice. This was demonstrated by the amelioration of weight loss, reduction in tissue inflammation score, and improvement in intestinal permeability. Moreover, AA suppressed the apoptosis of intestinal epithelial cells in Il-10-/- mice and LPS-induced colon organoids, while also reducing the levels of Bax and C-caspase-3. In terms of mechanism, AA suppressed the activation of TLR4 signaling in Il-10-/- mice and colon organoids induced by LPS. In addition, AA increased the abundance of short-chain fatty acid-producing bacteria in the stool of Il-10-/- mice, and transplantation of feces from AA-treated mice improved CD-like colitis. CONCLUSIONS: The results of our study demonstrate that AA has a protective effect on the intestinal barrier in Crohn's disease-like colitis by preventing apoptosis. Additionally, this groundbreaking study reveals the capacity of AA to hinder TLR4 signaling and alter the makeup of the intestinal microbiome. The findings present fresh possibilities for treating individuals diagnosed with Crohn's disease. AA offers a hopeful novel strategy for managing Crohn's disease by obstructing crucial pathways implicated in intestinal inflammation and enhancing the gut microbiota.


Assuntos
Colite , Doença de Crohn , Microbioma Gastrointestinal , Triterpenos , Camundongos , Animais , Doença de Crohn/tratamento farmacológico , Doença de Crohn/metabolismo , Doença de Crohn/patologia , Interleucina-10/metabolismo , Receptor 4 Toll-Like/metabolismo , Lipopolissacarídeos/efeitos adversos , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/metabolismo , Inflamação/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Sulfato de Dextrana/efeitos adversos , Colo/patologia
2.
ChemMedChem ; 15(12): 1089-1100, 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32233075

RESUMO

Gramicidin S (GS), one of the most widely investigated antimicrobial peptides (AMPs), is known for its robust antimicrobial activity. However, it is restricted to topical application due to undesired hemolytic activity. With the aim of obtaining nontoxic GS analogues, we describe herein a molecular approach in which the native GS ß-turn region is replaced by synthetic ß,γ-diamino acids (ß,γ-DiAAs). Four ß,γ-DiAA diastereomers were employed to mimic the ß-turn structure to afford GS analogues GS3-6, which exhibit diminished hemolytic activity. A comparative structural study demonstrates that the (ßR,γS)-DiAA is the most-stable ß-turn mimic. To further improve the therapeutic index (e. g., high antibacterial activity and low hemolytic activity) and to extend the molecular diversity, GS5 and GS6 were used as structural scaffolds to introduce additional hydrophobic or hydrophilic groups. We show that GS6K, GS6F and GS display comparable antibacterial activity, and GS6K and GS6F have significantly decreased toxicity. Moreover, antibacterial mechanism studies suggest that GS6K kills bacteria mainly through the disruption of the membrane.


Assuntos
Antibacterianos/farmacologia , Gramicidina/análogos & derivados , Gramicidina/farmacologia , Antibacterianos/síntese química , Antibacterianos/toxicidade , Bactérias/efeitos dos fármacos , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Gramicidina/toxicidade , Hemólise/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Estereoisomerismo
3.
Life Sci ; 239: 117021, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31678552

RESUMO

OBJECTIVES: Clematichinenoside AR (AR) is a saponin extracted for traditional Chinese medicine with the effects of improving the expression of tight junction (TJ) proteins and mediating anti-inflammatory activities. However, its effect on Crohn's disease (CD) is still unknown. We aimed to investigate the impact of AR on CD-like colitis and determine the mechanism underlying its effects. METHODS: Interleukin-10 gene knockout (Il-10-/-) mice (male, fifteen weeks old) with spontaneous colitis were allocated to the positive control and AR-treated (32 mg/kg AR administered every other day by gavage for 4 weeks) groups. Wild-type (WT) mice (male, fifteen weeks old) composed the negative control group. The effects of AR on intestinal barrier function and structure and T cell responses as well as the potential mechanisms underlying these effects were investigated. RESULTS: AR treatment significantly improved spontaneous colitis in Il-10-/- mice as demonstrated by reductions in the inflammatory score, disease activity index (DAI) and levels of inflammatory factors. The effects of AR on colitis in Il-10-/- mice were related to protecting intestinal barrier function and maintaining immune system homeostasis (regulatory T cell (Treg)/T helper 17 (Th17) cell balance). The anticolitis effect of AR may partly act by downregulating PI3K/Akt signaling. CONCLUSIONS: AR may have therapeutic potential for treating CD in humans.


Assuntos
Colite/tratamento farmacológico , Colite/genética , Interleucina-10/genética , Intestinos/patologia , Saponinas/uso terapêutico , Triterpenos/uso terapêutico , Animais , Translocação Bacteriana/efeitos dos fármacos , Colite/patologia , Citocinas/metabolismo , Intestinos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Reguladores/efeitos dos fármacos
4.
Afr J Tradit Complement Altern Med ; 13(4): 176-183, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28852734

RESUMO

BACKGROUND: The current study was designed to evaluate the effect of Platycodin D (PD), triterpenoid saponins extracted from the roots of Platycodon grandiflorum (PG) on alcohol-induced fatty liver (AFL) and investigate the possible mechanism. METHODS AND MATERIALS: A rat model was set up by feeding ethanol and fish oil to experimental rats, which then were treated with PD of 10, 20, 30 mg/kg body weight/day for 4 weeks, respectively, whereafter, liver function enzymes, endotoxin of serum and liver lipid were assayed by biochemical methods, cytokines, histochemistry of hepatic tissue, the protein expression of CD14 and TLR4, the mRNA expression of MD-2, MyD 88 and TRAF-6 were assayed. RESULTS: Treatment with PD on AFL rats significantly decreased the levels of serum ALT, AST and TBIL, coefficient of liver index and the hepatic tissue contents of TG, additionally and dramatically decreased serum endotoxin levels, down-regulated MD-2 and CD14 levels, as well as the mRNA expression of TLR4, MyD88 and TRAF-6, accordingly suppressed NF-κB: p65 as well as endotoxin-mediated inflammatory factors such as TNF-α and IL-6. CONCLUSIONS: Treatment with PD effectively protects against AFL through anti-inflammatory and anti-endotoxic process, and the confirmed mechanism is that PD treatment ameliorate alcoholic-induced liver injury mainly via TLR4-MyD88-NF-K: B signal path in AFL rat. List of Abbreviations: AFL: alcoholic-induced fatty liver, CD14: cluster of differentiation 14, LPS: lipopolysaccharide, LBP: lipopolysaccharide-binding protein, TLR4: toll-like receptor 4, MD-2: molecule myeloid differential protein-2, MyD 88: myeloid differentiation primary response protein 88, TRAF-6: TNF-receptor associated factor-6, NF-κB: nuclear transcription factor kappa B, IL-6: interleukin-6, TNF-α: tumor necrosis factor-α, PG: Platycodon grandiflorum, PD: Platycodin D.


Assuntos
Álcoois/efeitos adversos , Anti-Inflamatórios/administração & dosagem , Medicamentos de Ervas Chinesas/administração & dosagem , Fígado Gorduroso/tratamento farmacológico , NF-kappa B/metabolismo , Platycodon/química , Saponinas/administração & dosagem , Receptor 4 Toll-Like/metabolismo , Triterpenos/administração & dosagem , Animais , Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , NF-kappa B/genética , Raízes de Plantas/química , Ratos , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
5.
Nat Prod Res ; 29(1): 31-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25204856

RESUMO

In this study, a kind of green solvent named polyethylene glycol (PEG) was developed for the ultrasound-assisted extraction (UAE) of magnolol and honokiol from Cortex Magnoliae Officinalis. The effects of PEG molecular weight, PEG concentration, sample size, pH, ultrasonic power and extraction time on the extraction of magnolol and honokiol were investigated to optimise the extraction conditions. Under the optimal extraction conditions, the PEG-based UAE supplied higher extraction efficiencies of magnolol and honokiol than the ethanol-based UAE and traditional ethanol-reflux extraction. Furthermore, the correlation coefficient (R(2)), repeatability (relative standard deviation, n = 6) and recovery confirmed the validation of the proposed extraction method, which were 0.9993-0.9996, 3.1-4.6% and 92.3-106.8%, respectively.


Assuntos
Compostos de Bifenilo/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Lignanas/isolamento & purificação , Magnolia/química , Polietilenoglicóis/química , Ultrassom , Compostos de Bifenilo/química , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/química , Lignanas/química
6.
J Neurosci Res ; 87(13): 2854-62, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19472225

RESUMO

The extracellular matrix (ECM) is a component of neural cell niches and regulates multiple functions of diverse cell types. To date, limited information is available concerning its biological effects on the growth properties of oligodendrocyte progenitor cells (OPCs). In the present study, we examined effects of several ECM components, i.e., fibronectin, laminin, and Matrigel, on the survival, proliferation, migration, process extension, and purity of OPCs isolated from embryonic day 15 rat spinal cords. All three ECM components enhanced these biological properties of the OPCs compared with a non-ECM substrate, poly-D-lysine. However, the extents of their effects were somewhat different. Among these ECMs, fibronectin showed the strongest effect on almost all aspects of the growth properties of OPCs, implying that this molecule is a better substrate for the growth of OPCs in vitro. Because of its survival- and growth-promoting effects on OPCs, fibronectin may be considered as a candidate substrate for enhancing OPC-mediated repair under conditions when exogenous delivery or endogenous stimulation of OPCs is applied.


Assuntos
Proteínas da Matriz Extracelular/farmacologia , Células-Tronco Multipotentes/efeitos dos fármacos , Oligodendroglia/citologia , Animais , Apoptose/efeitos dos fármacos , Técnicas de Cultura de Células/instrumentação , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Extensões da Superfície Celular/efeitos dos fármacos , Extensões da Superfície Celular/ultraestrutura , Células Cultivadas/efeitos dos fármacos , Colágeno/farmacologia , Combinação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Fibronectinas/farmacologia , Laminina/farmacologia , Células-Tronco Multipotentes/citologia , Proteoglicanas/farmacologia , Ratos , Ratos Wistar , Medula Espinal/citologia , Medula Espinal/embriologia
7.
J Mol Neurosci ; 38(2): 103-13, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19148782

RESUMO

The present study was conducted to investigate whether Ginkgo biloba extract (EGb) 761 could protect spinal cord neurons from H(2)O(2)-induced toxicity. In primary spinal cord neurons isolated from embryonic day 14 rats, H(2)O(2) administration resulted in a significant decrease in the survival of spinal cord neurons. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and Hoechst 33342 nuclear staining showed that these cells die by apoptosis. Such neuronal death, however, was significantly reversed by EGb761 in a dose-dependent manner. Moreover, a marked increase in intracellular free radical generation was found after the H(2)O(2) administration which could be reversed almost completely by EGb761, indicating that inhibition of free radical generation is an important mechanism of the anti-apoptosis action of EGb761. Finally, treatment of cells with H(2)O(2) for 12 h reduced the expression of Bcl-2, an anti-apoptotic gene, by 70% but showed no effect on the level of Bax, a pro-apoptotic gene. EGb76 treatment, however, significantly reversed H(2)O(2)-induced reduction of Bcl-2 expression and inhibited Bax expression by 2.3-fold. Thus, our study provided evidence showing that the protective effect of EGb761 on spinal cord neuronal apoptosis after oxidative stress is mediated, at least in part, by its anti-oxidative action and regulation of apoptosis-related genes Bcl-2 and Bax.


Assuntos
Apoptose/genética , Peróxido de Hidrogênio/farmacologia , Neurônios , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Medula Espinal/citologia , Animais , Apoptose/fisiologia , Células Cultivadas , Feminino , Ginkgo biloba , Humanos , Marcação In Situ das Extremidades Cortadas , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Oxidantes/farmacologia , Oxirredução , Estresse Oxidativo , Gravidez , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Medula Espinal/patologia , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
8.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 32(5): 819-23, 2007 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-18007077

RESUMO

OBJECTIVE: To investigate the effect of decellular treatment on the framework constituents of extracellular matrix and tissue stability in bovine jugular vein conduit (BJVC), and to provide an evidence for tissue engineering of vascular prosthesis. METHODS: Bovine jugular veins were obtained fresh from a local slaughterhouse and were stored in chilled PBS. In the laboratory, any fat and loose connective tissue on the outer surface of the vessel was trimmed. BJVCs were decellularized by a 3-step extraction method as detergent Triton X-100 (0.5%), Trypsin (0.025%) EDTA (0.02%), and DNase I(30kU/L) RNaseA(0.3g/L). Histological and transmission electron microscopy (TEM) techniques were used to study the framework constituents of extracellular matrix of treated the examples, and fresh tissues were used as controls. Tissue contents of hydroxyproline(alkaline hydrolysis method) and elastin (Fastin Elastin Assay) were assayed respectively in the fresh and decellularized groups (n=10). The vascular wall heat shrinking temperature and mechanical strength were measured to evaluate the tissue stability (n=10). RESULTS: Histochemical and TEM analysis of BJVCs treated with decellularization proved a complete removal of nuclear and other cell components. Tissue collagen was well kept,but elastin was partly lessened. Tissue content of hydroxyproline increased comparatively [(25.73+/-2.97)mg/g vs. (29.25+/-2.99)mg/g, P<0.05] and the elastin content obviously decreased [(159.71+/-21.06)mg/g vs. (134.91+/-35.40)mg/g, P<0.05] in the decellular treatment group compared with the control group. The heat shrinking temperature and tensile stress of decelluarized tissue were lower than those of the fresh tissue[(72.50+/-0.53) degrees C vs. (69.75+/-0.54)degrees C ,P<0.05], [(5.19+/-0.65)MPa vs. (3.13+/-0.94)MPa, P<0.05]. CONCLUSION: The basic framework of extracellular matrix in the decellularized BJVC is partly damaged and tissue stability is reduced. Decellularized BJVC should be further crosslinked before being used as a tissue engineering scaffold for clinical pulmonary artery graft.


Assuntos
Prótese Vascular , Matriz Extracelular , Engenharia Tecidual/métodos , Alicerces Teciduais , Animais , Bovinos , Veias Jugulares
9.
J Biol Chem ; 278(48): 47365-9, 2003 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-12972424

RESUMO

Iron and oxygen are essential but potentially toxic constituents of most organisms, and their transport is meticulously regulated both at the cellular and systemic levels. Compartmentalization may be a homeostatic mechanism for isolating these biological reactants in cells. To investigate this hypothesis, we have undertaken a genetic analysis of the interaction between iron and oxygen metabolism in Drosophila. We show that Drosophila iron regulatory protein-1 (IRP1) registers cytosolic iron and oxidative stress through its labile iron sulfur cluster by switching between cytosolic aconitase and RNA-binding functions. IRP1 is strongly activated by silencing and genetic mutation of the cytosolic superoxide dismutase (Sod1), but is unaffected by silencing of mitochondrial Sod2. Conversely, mitochondrial aconitase activity is relatively insensitive to loss of Sod1 function, but drops dramatically if Sod2 activity is impaired. This strongly suggests that the mitochondrial boundary limits the range of superoxide reactivity in vivo. We also find that exposure of adults to paraquat converts cytosolic aconitase to IRP1 but has no affect on mitochondrial aconitase, indicating that paraquat generates superoxide in the cytosol but not in mitochondria. Accordingly, we find that transgene-mediated overexpression of Sod2 neither enhances paraquat resistance in Sod1+ flies nor compensates for lack of SOD1 activity in Sod1-null mutants. We conclude that in vivo, superoxide is confined to the subcellular compartment in which it is formed, and that the mitochondrial and cytosolic SODs provide independent protection to compartment-specific protein iron-sulfur clusters against attack by superoxide generated under oxidative stress within those compartments.


Assuntos
Proteínas Ferro-Enxofre/química , Superóxido Dismutase/química , Aconitato Hidratase/química , Animais , Linhagem Celular , Citosol/enzimologia , Citosol/metabolismo , DNA Complementar/metabolismo , Relação Dose-Resposta a Droga , Drosophila , Herbicidas , Ferro/metabolismo , Proteína 1 Reguladora do Ferro/metabolismo , Mitocôndrias/enzimologia , Mutação , Estresse Oxidativo , Oxigênio/metabolismo , Paraquat/farmacologia , Ligação Proteica , RNA/metabolismo , Interferência de RNA , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1 , Superóxidos , Fatores de Tempo , Transgenes
10.
Zhongguo Zhong Yao Za Zhi ; 28(2): 121-5, 2003 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-15015281

RESUMO

OBJECTIVE: To study the changes of soil fertility in Sheyang county where Chrysanthemum morifolium has been cultivated for more than 30 years and to develop the special fertilizer for cultivation of C. morifolium. METHOD: The pH values, organic matter and the contents of total and available N, P, K and Zn in the soil layer of 0 to 40 cm, as well as the total N, P, K and Zn contents in the flowers, roots, stems and leaves of the plants, were analysed. The balanced fertilization plan for cultivation of C. morifolium was put forward. In addition, the formula of special fertilizer for cultivation of C. morifolium was determined according to flower yield and utilization rate of N, P, and K. RESULTS AND CONCLUSION: The soil had high pH values and high soil salt contents, with unbalanced application of N, P, and K fertilizers and a shortage of available Zn after cultivation of C. morifolium. The contents of soil organic carbon, N and P declined with increasing cultivation time of C. morifolium, which resulted from the improper rotations and fertilization. The balance fertilization practice and the special fertilizer utilization are effective ways to improve soil fertility for C. morifolium.


Assuntos
Chrysanthemum/crescimento & desenvolvimento , Fertilizantes , Plantas Medicinais/crescimento & desenvolvimento , Solo/análise , Chrysanthemum/química , Concentração de Íons de Hidrogênio , Nitrogênio/análise , Fósforo/análise , Raízes de Plantas/química , Plantas Medicinais/química , Potássio/análise , Zinco/análise
11.
Zhongguo Zhong Yao Za Zhi ; 28(1): 28-31, 2003 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-15015262

RESUMO

OBJECTIVE: To investigate botanical characters and yield of four cultivars of Chrysanthemum morifolium for further study on their genetic diversity and selective breeding. METHOD: The characters were observed and yield was investigated by field randomized block and analysis of variance. RESULT AND CONCLUSION: The botanical characters are difference among four cultivars; the amount of single flower head is the main factor influencing on the output of Chrysanthemum morifolium (r = 0.925); the yield of "Hongxinju" and "Xiaobaiju" are remarkably higher than that of "Dabaiju" and "Changbanju".


Assuntos
Chrysanthemum/crescimento & desenvolvimento , Variação Genética , Plantas Medicinais/crescimento & desenvolvimento , Seleção Genética , Cruzamento , Chrysanthemum/anatomia & histologia , Chrysanthemum/genética , Plantas Medicinais/anatomia & histologia , Plantas Medicinais/genética
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