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1.
Nat Commun ; 15(1): 2390, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493199

RESUMO

Metal-halide perovskite thin monocrystals featuring efficient carrier collection and transport capabilities are well suited for radiation detectors, yet their growth in a generic, well-controlled manner remains challenging. Here, we reveal that mass transfer is one major limiting factor during solution growth of perovskite thin monocrystals. A general approach is developed to overcome synthetic limitation by using a high solute flux system, in which mass diffusion coefficient is improved from 1.7×10-10 to 5.4×10-10 m2 s-1 by suppressing monomer aggregation. The generality of this approach is validated by the synthesis of 29 types of perovskite thin monocrystals at 40-90 °C with the growth velocity up to 27.2 µm min-1. The as-grown perovskite monocrystals deliver a high X-ray sensitivity of 1.74×105 µC Gy-1 cm-2 without applied bias. The findings regarding limited mass transfer and high-flux crystallization are crucial towards advancing the preparation and application of perovskite thin monocrystals.

2.
Acta Pharmacol Sin ; 44(12): 2469-2478, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37580493

RESUMO

Intestinal fibrosis is a common complication of inflammatory bowel disease. There is still a lack of effective drugs for the prevention or treatment of intestinal fibrosis. Heat shock protein 47 (HSP47) plays a key role in the development of intestinal fibrosis. In this study we investigated the therapeutic potential and underlying mechanisms of fraxinellone, a degraded limonoid isolated from the root bark of Dictamnus dasycarpus, in the treatment of intestinal fibrosis. Intestinal fibrosis was induced in mice by dextran sodium sulfate (DSS) treatment. DDS-treated mice were administered fraxinellone (7.5, 15, 30 mg·kg-1·d-1, i.g.) for 45 days. We showed that fraxinellone administration dose-dependently alleviated DSS-induced intestinal impairments, and reduced the production of intestinal fibrosis biomarkers such as α-smooth muscle actin (SMA), collagen I, hydroxyproline, fibronectin and laminin, and cytokines such as TGF-ß, TNF-α and IL-ß. We then established in vitro intestinal fibrosis cell models in SW480 and HT-29 cells, and demonstrated that treatment with fraxinellone (3, 10, 30 µM) significantly relieved TGF-ß-induced fibrosis responses by inhibiting the TGF-ß/Smad2/3 signaling pathway. Molecular docking suggested that the fraxinellone might disrupt the interaction between HSP47 and collagen, which was confirmed by coimmunoprecipitation experiments. SPR analysis showed that fraxinellone had a high affinity for HSP47 with a Kd value of 3.542 × 10-5 M. This study provides a new example of HSP47-collagen intervention by a natural compound and has important implications for the clinical treatment of inflammation-induced issue fibrosis.


Assuntos
Colágeno , Proteínas de Choque Térmico HSP47 , Camundongos , Animais , Proteínas de Choque Térmico HSP47/metabolismo , Simulação de Acoplamento Molecular , Colágeno/metabolismo , Fibrose , Epitélio/metabolismo , Fator de Crescimento Transformador beta
3.
Artigo em Inglês | MEDLINE | ID: mdl-37410927

RESUMO

Plastic packaging waste, such as polyethylene terephthalate (PET) has increased significantly in recent decades, arousing a considerable and serious public concern regarding the environment, economy, and policy. Plastic recycling is a useful tool to mitigate this issue. Here, a feasible study was performed to investigate the potential of a novel method for identifying virgin and recycled PET. Ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) was combined with various chemometrics, as a simple and reliable method that achieved a high discrimination rate for 105 batches of virgin PET (v-PET) and recycled PET (r-PET) based on 202 non-volatile organic compounds (NVOCs). Making use of orthogonal partial least-squares discrimination analysis (OPLS-DA) together with non-parametric tests, 26 marker compounds (i.e. 12 intentionally added substances (IAS) and 14 non-intentionally added substances (NIAS) as well as 31 marker compounds (i.e. 11 IAS and 20 NIAS) obtained from positive and combination of positive and negative ionization modes of UPLC-Q-TOF-MS, respectively, were successfully identified. Moreover, 100% accuracy was obtained using a decision tree (DT). Cross-discrimination based on misclassified samples using various chemometrics allowed the prediction accuracy to be improved and to identify a large sample set, thus greatly enhancing the application scope of this method. The possible origins of these detected compounds can be the plastic itself, as well as contamination from food, medicine, pesticides, industry-related substances, and degradation and polymerization products. As many of these compounds are toxic, especially those pesticide related, this indicates an urgent requirement for closed loop recycling. Overall, this analytical method provides a quick, accurate, and robust way to distinguish virgin from recycled PET and thus addresses the issue of potential virgin PET adulteration thereby detecting fraud in the area of PET recycling.


Assuntos
Quimiometria , Polietilenotereftalatos , Polietilenotereftalatos/análise , Espectrometria de Massas/métodos , Cromatografia Líquida , Plásticos/análise , Cromatografia Líquida de Alta Pressão/métodos
5.
EBioMedicine ; 90: 104499, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36870200

RESUMO

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is a severe dose-limiting side effect of chemotherapy and remains a huge clinical challenge. Here, we explore the role of microcirculation hypoxia induced by neutrophil extracellular traps (NETs) in the development of CIPN and look for potential treatment. METHODS: The expression of NETs in plasma and dorsal root ganglion (DRG) are examined by ELISA, IHC, IF and Western blotting. IVIS Spectrum imaging and Laser Doppler Flow Metry are applied to explore the microcirculation hypoxia induced by NETs in the development of CIPN. Stroke Homing peptide (SHp)-guided deoxyribonuclease 1 (DNase1) is used to degrade NETs. FINDINGS: The level of NETs in patients received chemotherapy increases significantly. And NETs accumulate in the DRG and limbs in CIPN mice. It leads to disturbed microcirculation and ischemic status in limbs and sciatic nerves treated with oxaliplatin (L-OHP). Furthermore, targeting NETs with DNase1 significantly reduces the chemotherapy-induced mechanical hyperalgesia. The pharmacological or genetic inhibition on myeloperoxidase (MPO) or peptidyl arginine deiminase-4 (PAD4) dramatically improves microcirculation disturbance caused by L-OHP and prevents the development of CIPN in mice. INTERPRETATION: In addition to uncovering the role of NETs as a key element in the development of CIPN, our finding provides a potential therapeutic strategy that targeted degradation of NETs by SHp-guided DNase1 could be an effective treatment for CIPN. FUNDING: This study was funded by the National Natural Science Foundation of China81870870, 81971047, 81773798, 82271252; Natural Science Foundation of Jiangsu ProvinceBK20191253; Major Project of "Science and Technology Innovation Fund" of Nanjing Medical University2017NJMUCX004; Key R&D Program (Social Development) Project of Jiangsu ProvinceBE2019732; Nanjing Special Fund for Health Science and Technology DevelopmentYKK19170.


Assuntos
Antineoplásicos , Armadilhas Extracelulares , Doenças do Sistema Nervoso Periférico , Camundongos , Animais , Armadilhas Extracelulares/metabolismo , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Oxaliplatina/efeitos adversos , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Antineoplásicos/efeitos adversos
6.
Neural Regen Res ; 18(9): 2067-2074, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36926733

RESUMO

Opioids, such as morphine, are the most potent drugs used to treat pain. Long-term use results in high tolerance to morphine. High mobility group box-1 (HMGB1) has been shown to participate in neuropathic or inflammatory pain, but its role in morphine tolerance is unclear. In this study, we established rat and mouse models of morphine tolerance by intrathecal injection of morphine for 7 consecutive days. We found that morphine induced rat spinal cord neurons to release a large amount of HMGB1. HMGB1 regulated nuclear factor κB p65 phosphorylation and interleukin-1ß production by increasing Toll-like receptor 4 receptor expression in microglia, thereby inducing morphine tolerance. Glycyrrhizin, an HMGB1 inhibitor, markedly attenuated chronic morphine tolerance in the mouse model. Finally, compound C (adenosine 5'-monophosphate-activated protein kinase inhibitor) and zinc protoporphyrin (heme oxygenase-1 inhibitor) alleviated the morphine-induced release of HMGB1 and reduced nuclear factor κB p65 phosphorylation and interleukin-1ß production in a mouse model of morphine tolerance and an SH-SY5Y cell model of morphine tolerance, and alleviated morphine tolerance in the mouse model. These findings suggest that morphine induces HMGB1 release via the adenosine 5'-monophosphate-activated protein kinase/heme oxygenase-1 signaling pathway, and that inhibiting this signaling pathway can effectively reduce morphine tolerance.

7.
Angew Chem Int Ed Engl ; 61(28): e202202298, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35389544

RESUMO

Electrochemical CO2 -to-CO conversion provides a possible way to address problems associated with the greenhouse effect; however, developing low-cost electrocatalysts to mediate high-efficiency CO2 reduction remains a challenge on account of the limited understanding of the nature of the real active sites. Herein, we reveal the Znδ+ metalloid sites as the real active sites of stable nonstoichiometric ZnOx structure derived from Zn2 P2 O7 through operando X-ray absorption fine structure analysis in conjunction with evolutionary-algorithm-based global optimization. Furthermore, theoretical and experimental results demonstrated that Znδ+ metalloid active sites could facilitate the activation of CO2 and the hydrogenation of *CO2 , thus accelerating the CO2 -to-CO conversion. Our work establishes a critical fundamental understanding of the origin of the real active center in the zinc-based electrocatalysts for CO2 reduction reaction.

8.
J Pharm Biomed Anal ; 209: 114526, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-34915323

RESUMO

Pogostemon cablin Benth (PCB) is a well-known traditional Chinese medicine that has been used for treatment of many ailments for several centuries. In presently, the chemical profiling and quality control study of PCB has mainly concentrated on the volatile fractions. However, the non-volatile chemical profile of PCB was still unclear. In this study, 73 non-volatile constituents (i.e., 33 flavonoids, 21 organic acids, 9 phenylpropanoids, 4 sesquiterpenes, 3 alkaloids, and 3 other types of compounds) were identified and characterized in PCB using high performance liquid chromatography coupled with quadruple time-of-flight tandem mass spectrometry (HPLC-Q-TOF-MS). Meanwhile, to assess PCB samples, an established HPLC-Q-TOF-MS fingerprint was combined with multivariate statistical analysis that included similarity analysis (SA), hierarchical cluster analysis (HCA), principal component analysis (PCA), and orthogonal partial least squares-discriminant analysis (OPLS-DA). The PCB samples could be classified into two groups (herbal decoction pieces and processed medicinal materials), and acteoside, isoacteoside, 4',6-Dihydroxy-5,7-dimethoxyflavone, pachypodol and pogostone were screened as the potential chemical markers that attributed classification. In addition, nine representative components (pachypodol, vicenin-2, apigenin, rhamnocitrin, acteoside, isoacteoside, chlorogenic acid, azelaic acid and pogostone) in PCB were simultaneously determined by using an ultra-high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry (UPLC-QQQ-MS/MS). This study is the first to describe the chemical profile of PCB using liquid chromatography tandem mass spectrometry, which would improve our understanding of the substance basis of PCB and is helpful to the PCB further quality evaluation.


Assuntos
Medicamentos de Ervas Chinesas , Pogostemon , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/análise , Pogostemon/química , Espectrometria de Massas em Tandem
9.
An Acad Bras Cienc ; 93(suppl 1): e20200628, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33909810

RESUMO

SiTian is an ambitious ground-based all-sky optical monitoring project, developed by the Chinese Academy of Sciences. The concept is an integrated network of dozens of 1-m-class telescopes deployed partly in China and partly at various other sites around the world. The main science goals are the detection, identification and monitoring of optical transients (such as gravitational wave events, fast radio bursts, supernovae) on the largely unknown timescales of less than 1 day; SiTian will also provide a treasure trove of data for studies of AGN, quasars, variable stars, planets, asteroids, and microlensing events. To achieve those goals, SiTian will scan at least 10,000 square deg of sky every 30 min, down to a detection limit of $V \approx 21$ mag. The scans will produce simultaneous light-curves in 3 optical bands. In addition, SiTian will include at least three 4-m telescopes specifically allocated for follow-up spectroscopy of the most interesting targets. We plan to complete the installation of 72 telescopes by 2030 and start full scientific operations in 2032.


Assuntos
Planetas , Telescópios , China , Análise Espectral
10.
Front Cell Dev Biol ; 8: 269, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32500072

RESUMO

A major unresolved issue in treating pain is the paradoxical hyperalgesia produced by the gold-standard analgesic morphine and other opioids. Endoplasmic reticulum (ER) stress has been shown to contribute to neuropathic or inflammatory pain, but its roles in opioids-induced hyperalgesia (OIH) are elusive. Here, we provide the first direct evidence that ER stress is a significant driver of OIH. GRP78, the ER stress marker, is markedly upregulated in neurons in the spinal cord after chronic morphine treatment. At the same time, morphine induces the activation of three arms of unfolded protein response (UPR): inositol-requiring enzyme 1α/X-box binding protein 1 (IRE1α/XBP1), protein kinase RNA-like ER kinase/eukaryotic initiation factor 2 subunit alpha (PERK/eIF2α), and activating transcription factor 6 (ATF6). Notably, we found that inhibition on either IRE1α/XBP1 or ATF6, but not on PERK/eIF2α could attenuate the development of OIH. Consequently, ER stress induced by morphine enhances PKA-mediated phosphorylation of NMDA receptor subunit 1(NR1) and leads to OIH. We further showed that heat shock protein 70 (HSP70), a molecular chaperone involved in protein folding in ER, is heavily released from spinal neurons after morphine treatment upon the control of KATP channel. Glibenclamide, a classic KATP channel blocker that inhibits the efflux of HSP70 from cytoplasm to extracellular environment, or HSP70 overexpression in neurons, could markedly suppress morphine-induced ER stress and hyperalgesia. Taken together, our findings uncover the induction process and the central role of ER stress in the development of OIH and support a novel strategy for anti-OIH treatment.

11.
Brain Behav Immun ; 68: 111-122, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29017971

RESUMO

Postoperative pain is a common form of acute pain that, if not managed effectively, can become chronic pain. Evidence has shown that glia, especially microglia, mediate neuroinflammation, which plays a vital role in pain sensitization. Moreover, toll-like receptor 4 (TLR4), the tumor necrosis factor receptor (TNF-R), the interleukin-1 receptor (IL-1R), and the interleukin-6 receptor (IL-6R) have been considered key components in central pain sensitization and neuroinflammation. Therefore, we hypothesized that activation of the body's endogenous "immune brakes" will inhibit these receptors and achieve inflammation tolerance as well as relieve postoperative pain. After searching for potential candidates to serve as this immune brake, we identified and focused on the suppressor of cytokine signaling 3 (SOCS3) gene. To regulate SOCS3 expression, we used paeoniflorin to induce heat shock protein 70 (HSP70)/TLR4 signaling. We found that paeoniflorin significantly induced SOCS3 expression both in vitro and in vivo and promoted the efflux of HSP70 from the cytoplasm to the extracellular environment. Furthermore, paeoniflorin markedly attenuated incision-induced mechanical allodynia, and this effect was abolished by small interfering RNAs targeting SOCS3. These findings demonstrated an effective and safe strategy to alleviate postoperative pain.


Assuntos
Dor Pós-Operatória/imunologia , Dor Pós-Operatória/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas/fisiologia , Animais , Citocinas/metabolismo , Tolerância a Medicamentos/fisiologia , Glucosídeos/farmacologia , Proteínas de Choque Térmico HSP70/metabolismo , Hiperalgesia/metabolismo , Inflamação/metabolismo , Camundongos , Microglia/fisiologia , Monoterpenos/farmacologia , Neuralgia/metabolismo , Neuroglia/fisiologia , Neuroimunomodulação/fisiologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Proteína 3 Supressora da Sinalização de Citocinas/genética , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Receptor 4 Toll-Like/metabolismo
12.
J Invest Dermatol ; 135(9): 2273-2282, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25897829

RESUMO

Phosphatase of regenerating liver-3 (PRL-3) has been reported to have a critical role in metastatic progression of cancers. Here, we investigate how PRL-3 increases the malignant degree of melanoma cells. The expression of PRL-3 increased gradually during the malignant progression of melanoma. The phosphorylation of Akt was elevated in highly malignant melanoma cells, which was accompanied by a decrease in nuclear phosphatase and tensin homolog (PTEN). The phosphorylation of NHERF1 in the serine site was regulated by PRL-3 and showed cytoplasmic translocation upon dephosphorylation, which resulted in a decrease in nuclear PTEN. The co-translocation of NHERF1 and PTEN from the nucleus to the cytoplasm was observed during the malignant progression of melanoma cells. Tumor growth was inhibited significantly, and the survival was prolonged upon knockdown of cytoplasmic NHERF1 in B16BL6 cells prior to the inoculation into mice. Taken together, to our knowledge previously unreported, we have identified NHERF1 as a potential substrate of PRL-3. Its phosphorylation status as well as its change in cellular localization and association with PTEN correlated with the malignant progression of melanoma. Our data provide an explanation for how PRL-3 promotes the malignant progression of melanoma, as well as a diagnostic marker or therapeutic target for malignant melanoma.


Assuntos
Biomarcadores Tumorais/metabolismo , Núcleo Celular/metabolismo , Proteínas Imediatamente Precoces/metabolismo , Fosfoproteínas/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , Análise de Variância , Animais , Linhagem Celular Tumoral , Proliferação de Células , Citoplasma/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Feminino , Humanos , Proteínas Imediatamente Precoces/genética , Melanoma/patologia , Melanoma/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Fosfoproteínas/genética , Fosforilação , Proteínas Tirosina Fosfatases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Sensibilidade e Especificidade , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/fisiopatologia , Trocadores de Sódio-Hidrogênio/genética
13.
J Basic Microbiol ; 55(7): 907-21, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25709086

RESUMO

Rhizopus oryzae is valuable as a producer of organic acids via lignocellulose catalysis. R. oryzae metabolizes xylose, which is one component of lignocellulose hydrolysate. In this study, a novel NADPH-dependent xylose reductase gene from R. oryzae AS 3.819 (Roxr) was cloned and expressed in Pichia pastoris GS115. Homology alignment suggested that the 320-residue protein contained domains and active sites belonging to the aldo/keto reductase family. SDS-PAGE demonstrated that the recombinant xylose reductase has a molecular weight of approximately 37 kDa. The optimal catalytic pH and temperature of the purified recombinant protein were 5.8 and 50 °C, respectively. The recombinant protein was stable from pH 4.4 to 6.5 and at temperatures below 42 °C. The recombinant enzyme has bias for D-xylose and L-arabinose as substrates and NADPH as its coenzyme. Real-time quantitative reverse transcription PCR tests suggested that native Roxr expression is regulated by a carbon catabolite repression mechanism. Site-directed mutagenesis at two possible key sites involved in coenzyme binding, Thr(226) → Glu(226) and Val(274) → Asn(274), were performed, respectively. The coenzyme specificity constants of the resulted RoXR(T226E) and RoXR(V274N) for NADH increased 18.2-fold and 2.4-fold, which suggested possibility to improve the NADH preference of this enzyme through genetic modification.


Assuntos
Aldeído Redutase/genética , Aldeído Redutase/metabolismo , Rhizopus/enzimologia , Rhizopus/genética , Aldeído Redutase/química , Aldeído Redutase/isolamento & purificação , Arabinose/metabolismo , Clonagem Molecular , Coenzimas/metabolismo , Eletroforese em Gel de Poliacrilamida , Cinética , Mutagênese Sítio-Dirigida , Pichia/genética , Proteínas Recombinantes/metabolismo , Rhizopus/metabolismo , Especificidade por Substrato , Xilose/metabolismo
14.
Phys Rev Lett ; 115(26): 261101, 2015 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-26764982

RESUMO

The accuracy of Einstein's equivalence principle (EEP) can be tested with the observed time delays between correlated particles or photons that are emitted from astronomical sources. Assuming as a lower limit that the time delays are caused mainly by the gravitational potential of the Milky Way, we prove that fast radio bursts (FRBs) of cosmological origin can be used to constrain the EEP with high accuracy. Taking FRB 110220 and two possible FRB/gamma-ray burst (GRB) association systems (FRB/GRB 101011A and FRB/GRB 100704A) as examples, we obtain a strict upper limit on the differences of the parametrized post-Newtonian parameter γ values as low as [γ(1.23 GHz)-γ(1.45 GHz)]<4.36×10(-9). This provides the most stringent limit up to date on the EEP through the relative differential variations of the γ parameter at radio energies, improving by 1 to 2 orders of magnitude the previous results at other energies based on supernova 1987A and GRBs.

15.
Toxicol Appl Pharmacol ; 281(1): 146-56, 2014 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-25448682

RESUMO

Inflammatory bowel disease (IBD) affects millions of people worldwide. Although the etiology of this disease is uncertain, accumulating evidence indicates a key role for the activated mucosal immune system. In the present study, we examined the effects of the natural compound fraxinellone on dextran sulfate sodium (DSS)-induced colitis in mice, an animal model that mimics IBD. Treatment with fraxinellone significantly reduced weight loss and diarrhea in mice and alleviated the macroscopic and microscopic signs of the disease. In addition, the activities of myeloperoxidase and alkaline phosphatase were markedly suppressed, while the levels of glutathione were increased in colitis tissues following fraxinellone treatment. This compound also decreased the colonic levels of interleukin (IL)-1ß, IL-6, IL-18 and tumor necrosis factor (TNF)-α in a concentration-dependent manner. These effects of fraxinellone in mice with experimental colitis were attributed to its inhibition of CD11b(+) macrophage infiltration. The mRNA levels of macrophage-related molecules in the colon, including intercellular adhesion molecule 1 (ICAM1), vascular cell adhesion molecule 1 (VCAM1), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2), were also markedly inhibited following fraxinellone treatment. The results from in vitro assays showed that fraxinellone significantly reduced lipopolysaccharide (LPS)-induced production of nitric oxide (NO), IL-1ß and IL-18 as well as the activity of iNOS in both THP-1 cells and mouse primary peritoneal macrophages. The mechanisms responsible for these effects were attributed to the inhibitory role of fraxinellone in NF-κB signaling and NLRP3 inflammasome activation. Overall, our results support fraxinellone as a novel drug candidate in the treatment of colonic inflammation.


Assuntos
Benzofuranos/farmacologia , Colite/metabolismo , Modelos Animais de Doenças , Macrófagos Peritoneais/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Animais , Benzofuranos/uso terapêutico , Linhagem Celular , Colite/induzido quimicamente , Colite/tratamento farmacológico , Sulfato de Dextrana/toxicidade , Relação Dose-Resposta a Droga , Humanos , Inflamassomos/antagonistas & inibidores , Inflamassomos/metabolismo , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
16.
Plant Sci ; 215-216: 190-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24388530

RESUMO

Chitinases are a group of pathogenesis-related proteins. The Brassica juncea chitinase gene BjCHI1 is highly inducible by pathogenic fungal infection, suggesting that the promoter of BjCHI1 might contain specific cis-acting element responsive to fungal attack. To identify the fungus-responsive element in BjCHI1 promoter (BjC-P), a series of binary plant transformation vectors were constructed by fusing the BjC-P or its deletion-derivatives to ß-glucuronidase (GUS) reporter gene. Expression of the GUS reporter gene was systematically assayed by a transient gene expression system in Nicotiana benthamiana leaves treated with fungal elicitor Hexa-N-Acetyl-Chitohexaose, as well as in transgenic Arabidopsis plants inoculated with fungus Botrytis cinerea. The histochemical and quantitative GUS assays showed that the W-box-like element (GTAGTGACTCAT) in the region (-668 to -657) was necessary for the fungus-response, although there were another five W-box-like elements in BjC-P. In addition, gain-of-function analysis demonstrated that the fragment (-409 to -337) coupled to the W-box-like element was needed for full magnitude of the fungal induction. These results revealed the existence of a novel regulation mechanism of W-box-like element involved in plant pathogenic resistance, and will benefit the potential application of BjC-P in engineering crops.


Assuntos
Quitinases/genética , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Mostardeira/genética , Regiões Promotoras Genéticas , Sequências Reguladoras de Ácido Nucleico , Arabidopsis/genética , Arabidopsis/microbiologia , Botrytis , Quitinases/metabolismo , Genes Reporter , Glucuronidase/genética , Mostardeira/metabolismo , Mostardeira/microbiologia , Oligossacarídeos/farmacologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Nicotiana/efeitos dos fármacos , Nicotiana/genética
17.
PLoS One ; 8(12): e83013, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24340073

RESUMO

Crohn's disease is a common, chronic inflammatory bowel condition characterized by remission and relapse. Accumulating evidence indicates that activated T cells play an important role in this disease. In the present study, we aimed to examine the effect of beauvericin, a natural cyclic peptide, on 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice, which mimics Crohn's disease. Beauvericin significantly reduced weight loss, diarrhea and mortality, accompanied with notable alleviation of macroscopic and microscopic signs. In addition, this compound decreased serum levels of tumor necrosis factor (TNF)-α and interferon (IFN)-γ in a concentration-dependent manner in mice with experimental colitis. These effects of beauvericin are attributed to its inhibition on activated T cells. Flow cytometry and immunoblot assay data showed that beauvericin suppressed T-cell proliferation, activation and IFN-γ-STAT1-T-bet signaling and subsequently led to apoptosis of activated T cells by suppressing Bcl-2 and phosphorylated Bad as well as increasing cleavage of caspase-3, -9, -12 and PARP. Furthermore, inhibition of PI3K/Akt signaling, which was an upstream regulator of cell activation and survival in activated T cells, contributed to the effect of beauvericin. Overall, these results supported beauvericin as a novel drug candidate for the treatment of colonic inflammation mainly by targeting PI3K/Akt in activated T cells.


Assuntos
Colite/tratamento farmacológico , Depsipeptídeos/uso terapêutico , Regulação Enzimológica da Expressão Gênica , Transdução de Sinais , Linfócitos T/efeitos dos fármacos , Animais , Apoptose , Proliferação de Células/efeitos dos fármacos , Colite/induzido quimicamente , Modelos Animais de Doenças , Regulação para Baixo , Feminino , Citometria de Fluxo , Inflamação , Interferon gama/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ácido Trinitrobenzenossulfônico/química , Fator de Necrose Tumoral alfa/metabolismo
18.
Toxicol Appl Pharmacol ; 267(2): 167-73, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23276654

RESUMO

In the present study, we aimed to investigate the immunosuppressive activity of vaticaffinol, a resveratrol tetramer isolated from Vatica mangachapoi, on T lymphocytes both in vitro and in vivo, and further explored its potential molecular mechanism. Resveratrol had a wide spectrum of healthy beneficial effects with multiple targets. Interestingly, its tetramer, vaticaffinol, exerted more intensive immunosuppressive activity than resveratrol. Vaticaffinol significantly inhibited T cells proliferation activated by concanavalin A (Con A) or anti-CD3 plus anti-CD28 in a dose- and time-dependent manner. It also induced Con A-activated T cells undergoing apoptosis through mitochondrial pathway. Moreover, this compound prevented cells from entering S phase and G2/M phase during T cells activation. In addition, vaticaffinol inhibited ERK and AKT signaling pathways in Con A-activated T cells. Furthermore, vaticaffinol significantly ameliorated ear swelling in a mouse model of picryl chloride-induced ear contact dermatitis in vivo. In most of the aforementioned experiments, however, resveratrol had only slight effects on the inhibition of T lymphocytes compared with vaticaffinol. Taken together, our findings suggest that vaticaffinol exerts more preferable immunosuppressive activity than its precursor resveratrol both in vitro and in vivo by affecting multiple targets against activated T cells.


Assuntos
Imunossupressores/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Estilbenos/química , Estilbenos/farmacologia , Linfócitos T/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Dermatite de Contato/tratamento farmacológico , Feminino , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Resveratrol
19.
Toxicol Appl Pharmacol ; 267(1): 95-103, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23274515

RESUMO

In the present paper, we examined the effects of a natural cyclopeptide RA-V on human breast cancer cells and the underlying mechanisms. RA-V significantly inhibited the growth of human breast cancer MCF-7, MDA-MB-231 cells and murine breast cancer 4T1 cells. In addition, RA-V triggered mitochondrial apoptotic pathway which was indicated by the loss of mitochondrial membrane potential, the release of cytochrome c, and the activation of caspase cascade. Further study showed that RA-V dramatically inhibited phosphorylation of AKT and 3-phosphoinositide dependent protein kinase 1 (PDK1) in MCF-7 cells. Moreover, RA-V disrupted the interaction between PDK1 and AKT in MCF-7 cells. Furthermore, RA-V-induced apoptosis could be enhanced by phosphatidylinositol 3-kinase inhibitor or attenuated by over-expression of AKT in all the three kinds of breast cancer cells. Taken together, this study shows that RA-V, which can induce mitochondria-mediated apoptosis, exerts strong anti-tumor activity against human breast cancer. The underlying anti-cancer mechanism of RA-V is related to the blockage of the interaction between PDK1 and AKT.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/metabolismo , Mitocôndrias/fisiologia , Peptídeos Cíclicos/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Mitocôndrias/efeitos dos fármacos , Peptídeos Cíclicos/química , Peptídeos Cíclicos/uso terapêutico , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Mapeamento de Interação de Proteínas , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Piruvato Desidrogenase Quinase de Transferência de Acetil
20.
Biochem Pharmacol ; 84(9): 1164-73, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22902832

RESUMO

Dysregulation of signal transducer and activator of transcription (STAT) signaling is usually associated with intricate immune diseases and rebuilding the balance of STAT1 and STAT3 signaling is being explored as a useful approach for the treatment of these diseases. However, few chemicals have been reported to rebuild the balance of these two signalings for immune hepatitis therapy. In the present study, we found that fusaruside, a new kind of cerebroside isolated from an endophytic fungus Fusarium sp. IFB-121 in Quercus variabilis, significantly ameliorated concanavalin A (Con A)-induced T-cell-mediated fulminant hepatitis in mice, which was closely associated with the improvement of histopathological parameters, inhibition of activation of liver CD4(+) T cells and NKT cells, regulation of balance of Th1/Th2/Th17/Treg cytokines and protection of hepatocyte from apoptosis. Moreover, T-cell proliferation and activation was also notably inhibited by fusaruside in vitro. Furthermore, the protective effect of fusaruside was attributable to a novel regulatory mechanism through down-regulating STAT1 activation and T-bet expression in liver CD4(+) T cells and up-regulating STAT3 activation and Bcl-X(L) expression in hepatocytes. In conclusion, fusaruside exhibited its capability against T-cell-mediated liver injury in vivo, through rebuilding the balance of STAT1 and STAT3 signalings. These results suggest that fusaruside is potentially useful for the treatment of T-cell-mediated human liver disorders.


Assuntos
Cerebrosídeos/farmacologia , Hepatite Animal/tratamento farmacológico , Falência Hepática Aguda/tratamento farmacológico , Fator de Transcrição STAT1/fisiologia , Fator de Transcrição STAT2/fisiologia , Linfócitos T/efeitos dos fármacos , Animais , Antígenos CD4/metabolismo , Proliferação de Células/efeitos dos fármacos , Cerebrosídeos/isolamento & purificação , Concanavalina A , Citocinas/metabolismo , Feminino , Fusarium/química , Hepatite Animal/etiologia , Hepatite Animal/imunologia , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/patologia , Falência Hepática Aguda/etiologia , Falência Hepática Aguda/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Células T Matadoras Naturais/efeitos dos fármacos , Células T Matadoras Naturais/imunologia , Células T Matadoras Naturais/patologia , Transdução de Sinais , Baço/efeitos dos fármacos , Baço/imunologia , Baço/patologia , Linfócitos T/imunologia , Linfócitos T/patologia , Proteína bcl-X/metabolismo
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