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1.
Proc Natl Acad Sci U S A ; 118(14)2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33795513

RESUMO

Plants sense and integrate diverse stimuli to determine the timing for germination. A smoke compound, 3,4,5-trimethylfuran-2(5H)-one (trimethylbutenolide, TMB), has been identified to inhibit the seed germination of higher plants. To understand the mode of action, we examined various physiological and molecular aspects of the TMB-dependent inhibition of seed germination in Arabidopsis thaliana The results indicated that the effect of TMB is due to the enhanced physiological dormancy, which is modulated by other dormancy regulatory cues such as after-ripening, stratification, and ABA/GA signaling. In addition, gene expression profiling showed that TMB caused genome-wide transcriptional changes, altering the expression of a series of dormancy-related genes. Based on the TMB-responsive physiological contexts in Arabidopsis, we performed mutant screening to isolate genetic components that underpin the TMB-induced seed dormancy. As a result, the TMB-RESISTANT1 (TES1) gene in Arabidopsis, encoding a B2 group Raf-like kinase, was identified. Phenotypic analysis of the tes1 mutant implicated that TES1 has a critical role in the TMB-responsive gene expression and the inhibition of seed germination. Taken together, we propose that plants have been equipped with a TMB sensory pathway through which the TMB induces the seed dormancy in a TES1-dependent way.


Assuntos
Furanos/farmacologia , Dormência de Plantas , Sementes/metabolismo , Arabidopsis , Resistência a Medicamentos , Germinação , Sementes/efeitos dos fármacos , Fumaça
2.
J Korean Med Sci ; 38(11): e77, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36942391

RESUMO

BACKGROUND: Autoencoder (AE) is one of the deep learning techniques that uses an artificial neural network to reconstruct its input data in the output layer. We constructed a novel supervised AE model and tested its performance in the prediction of a co-existence of the disease of interest only using diagnostic codes. METHODS: Diagnostic codes of one million randomly sampled patients listed in the Korean National Health Information Database in 2019 were used to train, validate, and test the prediction model. The first used AE solely for a feature engineering tool for an input of a classifier. Supervised Multi-Layer Perceptron (sMLP) was added to train a classifier to predict a binary level with latent representation as an input (AE + sMLP). The second model simultaneously updated the parameters in the AE and the connected MLP classifier during the learning process (End-to-End Supervised AE [EEsAE]). We tested the performances of these two models against baseline models, eXtreme Gradient Boosting (XGB) and naïve Bayes, in the prediction of co-existing gastric cancer diagnosis. RESULTS: The proposed EEsAE model yielded the highest F1-score and highest area under the curve (0.86). The EEsAE and AE + sMLP gave the highest recalls. XGB yielded the highest precision. Ablation study revealed that iron deficiency anemia, gastroesophageal reflux disease, essential hypertension, gastric ulcers, benign prostate hyperplasia, and shoulder lesion were the top 6 most influential diagnoses on performance. CONCLUSION: A novel EEsAE model showed promising performance in the prediction of a disease of interest.


Assuntos
Aprendizado Profundo , Masculino , Humanos , Teorema de Bayes , Redes Neurais de Computação
3.
Int J Mol Sci ; 22(14)2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34299128

RESUMO

Stroke is one of the leading causes of death and disability worldwide. However, treatment options for ischemic stroke remain limited. Matrix-metalloproteinases (MMPs) contribute to brain damage during ischemic strokes by disrupting the blood-brain barrier (BBB) and causing brain edemas. Carnosine, an endogenous dipeptide, was found by us and others to be protective against ischemic brain injury. In this study, we investigated whether carnosine influences MMP activity. Brain MMP levels and activity were measured by gelatin zymography after permanent occlusion of the middle cerebral artery (pMCAO) in rats and in vitro enzyme assays. Carnosine significantly reduced infarct volume and edema. Gelatin zymography and in vitro enzyme assays showed that carnosine inhibited brain MMPs. We showed that carnosine inhibited both MMP-2 and MMP-9 activity by chelating zinc. Carnosine also reduced the ischemia-mediated degradation of the tight junction proteins that comprise the BBB. In summary, our findings show that carnosine inhibits MMP activity by chelating zinc, an essential MMP co-factor, resulting in the reduction of edema and brain injury. We believe that our findings shed new light on the neuroprotective mechanism of carnosine against ischemic brain damage.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Carnosina/farmacologia , Infarto da Artéria Cerebral Média/complicações , Metaloproteinase 2 da Matriz/química , Metaloproteinase 9 da Matriz/química , Inibidores de Metaloproteinases de Matriz/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Isquemia Encefálica/enzimologia , Isquemia Encefálica/etiologia , Isquemia Encefálica/patologia , Feminino , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/enzimologia , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/patologia
4.
Int J Mol Sci ; 23(1)2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35008607

RESUMO

Recent studies on the pathophysiology of irritable bowel syndrome (IBS) have focused on the role of mast cells (MCs) in intestinal mucosal immunity. A link between allergic airway diseases (AADs) and IBS has been suggested because both diseases have similar pathophysiology. We aimed to investigate whether the induction of AAD in mice could lead to inflammation of the colonic mucosa, similar to IBS. We also evaluated whether this inflammatory response could be suppressed by administering a therapeutic agent. Mice were divided into three groups: control, AAD-induced, and salbutamol-treated. An AAD mouse model was established by intraperitoneal injection and nasal challenge with ovalbumin. Mice with AAD were intranasally administered salbutamol. Analyses of cytokine levels, MC count, and tryptase levels in the intestinal mucosa were performed to compare the changes in inflammatory responses among the three groups. Inflammation was observed in the intestinal mucosa of mice in the AAD group. This inflammation in AAD mice was suppressed after salbutamol treatment. Our study demonstrates that AAD induces an inflammatory response similar to that in IBS, suggesting a possible association between IBS and AADs. In patients with IBS with such allergic components, salbutamol may have the potential to alleviate the inflammatory response.


Assuntos
Albuterol/uso terapêutico , Inflamação , Mucosa Intestinal/imunologia , Síndrome do Intestino Irritável/induzido quimicamente , Ovalbumina/toxicidade , Hipersensibilidade Respiratória/induzido quimicamente , Administração Intranasal , Animais , Modelos Animais de Doenças , Mucosa Intestinal/patologia , Síndrome do Intestino Irritável/tratamento farmacológico , Síndrome do Intestino Irritável/imunologia , Masculino , Mastócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/administração & dosagem , Ovalbumina/efeitos adversos , Hipersensibilidade Respiratória/tratamento farmacológico , Hipersensibilidade Respiratória/imunologia
5.
Molecules ; 26(17)2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34500680

RESUMO

The pharmacokinetic (PK) change in a drug by co-administered herbal products can alter the efficacy and toxicity. In the circumstances that herb-drug combinations have been increasingly attempted to alleviate Alzheimer's disease (AD), the PK evaluation of herb-drug interaction (HDI) is necessary. The change in systemic exposure as well as target tissue distribution of the drug have been issued in HDIs. Recently, the memory-enhancing effects of water extract of mangosteen pericarp (WMP) has been reported, suggesting a potential for the combination of WMP and donepezil (DNP) for AD treatment. Thus, it was evaluated how WMP affects the PK change of donepezil, including systemic exposure and tissue distribution in mice after simultaneous oral administration of DNP with WMP. Firstly, co-treatment of WMP and donepezil showed a stronger inhibitory effect (by 23.0%) on the neurotoxicity induced by Aß(25-35) in SH-SY5Y neuroblastoma cells than donepezil alone, suggesting that the combination of WMP and donepezil may be more effective in moderating neurotoxicity than donepezil alone. In PK interaction, WMP increased donepezil concentration in the brain at 4 h (by 63.6%) after administration without affecting systemic exposure of donepezil. Taken together, our results suggest that WMP might be used in combination with DNP as a therapy for AD.


Assuntos
Donepezila/química , Garcinia mangostana/química , Água/química , Doença de Alzheimer/metabolismo , Animais , Encéfalo , Modelos Animais de Doenças , Camundongos
6.
Xenobiotica ; 50(7): 863-874, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31791185

RESUMO

1. Treatment periods of P-glycoprotein (P-gp) inhibitors have revealed different efficacies. We have previously reported dose-dependent inhibition of P-gp in single-treatment with LC478. However, whether repeated treatment with LC478 can inhibit P-gp even at its ineffective single-treatment dose remains unknown. 2. Therefore, the purpose of this study was to assess the effect of repeated treatment (i.e., 7-day treatment) with LC478 on P-gp known to affect docetaxel bioavailability in rats. Effects of LC478 on P-gp mediated efflux and expression in MDCK-MDR1 cells, P-gp ATPase activity, and binding site with P-gp were evaluated.3. The 7-day treatment with LC478 increased docetaxel absorption via intestinal P-gp inhibition in rats. Intestinal concentrations of LC478 were 8.31-10.3 µM in rats after 7-day treatment of LC478. These concentrations were close to 10 µM that reduced P-gp mediated docetaxel efflux and P-gp expression in MDCK-MDR1 cells. Considering that intestinal LC478 concentrations after 1-day treatment were 2.68-4.19 µM, higher LC478 concentrations after 7-day treatment might have driven P-gp inhibition and increased docetaxel absorption. LC478 might competitively inhibit P-gp considering its stimulated ATPase activity and its binding site with nucleotide binding domain of P-gp. 4. Therefore, repeated treatment with LC478 can determine its feasibility for P-gp inhibition and changing docetaxel bioavailability.


Assuntos
Adamantano/análogos & derivados , Adamantano/metabolismo , Antineoplásicos/farmacocinética , Docetaxel/farmacocinética , Inibidores Enzimáticos/farmacocinética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Adamantano/farmacocinética , Animais , Disponibilidade Biológica , Transporte Biológico , Absorção Intestinal , Ratos
7.
Int J Mol Sci ; 21(9)2020 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-32357505

RESUMO

l-carnosine is an attractive therapeutic agent for acute ischemic stroke based on its robust preclinical cerebroprotective properties and wide therapeutic time window. However, large doses are needed for efficacy because carnosine is rapidly degraded in serum by carnosinases. The need for large doses could be particularly problematic when translating to human studies, as humans have much higher levels of serum carnosinases. We hypothesized that d-carnosine, which is not a substrate for carnosinases, may have a better pharmacological profile and may be more efficacious at lower doses than l-carnosine. To test our hypothesis, we explored the comparative pharmacokinetics and neuroprotective properties of d- and L-carnosine in acute ischaemic stroke in mice. We initially investigated the pharmacokinetics of d- and L-carnosine in serum and brain after intravenous (IV) injection in mice. We then investigated the comparative efficacy of d- and l-carnosine in a mouse model of transient focal cerebral ischemia followed by in vitro testing against excitotoxicity and free radical generation using primary neuronal cultures. The pharmacokinetics of d- and l-carnosine were similar in serum and brain after IV injection in mice. Both d- and l-carnosine exhibited similar efficacy against mouse focal cerebral ischemia. In vitro studies in neurons showed protection against excitotoxicity and the accumulation of free radicals. d- and l-carnosine exhibit similar pharmacokinetics and have similar efficacy against experimental stroke in mice. Since humans have far higher levels of carnosinases, d-carnosine may have more favorable pharmacokinetics in future human studies.


Assuntos
Carnosina/administração & dosagem , AVC Isquêmico/tratamento farmacológico , Neurônios/citologia , Fármacos Neuroprotetores/administração & dosagem , Animais , Química Encefálica , Carnosina/química , Carnosina/farmacocinética , Células Cultivadas , Modelos Animais de Doenças , Humanos , Injeções Intravenosas , AVC Isquêmico/sangue , Masculino , Camundongos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacocinética , Cultura Primária de Células
8.
Molecules ; 25(15)2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32752108

RESUMO

An effective analytical method was optimized for residues including chlorpyrifos-methyl, deltamethrin, fenoxanil, thiobencarb and fludioxonil in mealworms, the larval form of Tenebrio molitor. They are listed for pest control during wheat cultivation and can be found in wheat-bran feed for growing mealworms in South Korea. Analytes were extracted using acetonitrile and salt packet. Four clean-up methods ((1) MgSO4 + 25 mg PSA + 25 mg C18; (2) MgSO4 + 50 mg PSA + 50 mg C18; (3) EMR-lipidTM tube; and (4) 10 mL n-hexane) were investigated and the method (1) was selected due to its robustness. Low-temperature precipitation of fat and proteins improved the recoveries. Recoveries from the Method (1) were satisfying with 70-120% with <20% relative SD at a spiking level of 0.01 mg/kg. With the simultaneous sample preparation, fenoxanil, thiobencarb and fludioxonil were analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS) and chlorpyrifos-methyl and deltamethrin by gas chromatography tandem mass spectrometry (GC-MS/MS). Quantification limits for LC-MS/MS and GC-MS/MS were 0.5 and 2.5 µg/L, respectively. No pesticides of interest were detected in 30 real samples collected across the nation. However, the data can be provided for establishing maximum residue limits for the pesticides in mealworms in response to the positive list system.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Tenebrio/química , Animais , Clorpirifos/análogos & derivados , Clorpirifos/análise , Clorpirifos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Imidazóis/análise , Imidazóis/isolamento & purificação , Larva/química , Larva/metabolismo , Limite de Detecção , Extração Líquido-Líquido , Nitrilas/análise , Nitrilas/isolamento & purificação , Resíduos de Praguicidas/isolamento & purificação , Piretrinas/análise , Piretrinas/isolamento & purificação , Tenebrio/crescimento & desenvolvimento , Tenebrio/metabolismo
9.
Int J Mol Sci ; 20(4)2019 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-30781591

RESUMO

A PACLOBUTRAZOL-RESISTANCE (PRE) gene family, consisting of six genes in Arabidopsis thaliana, encodes a group of helix-loop-helix proteins that act in the growth-promoting transcriptional network. To delineate the specific role of each of the PRE genes in organ growth, we took a reverse genetic approach by constructing high order pre loss-of-function mutants of Arabidopsis thaliana. In addition to dwarf vegetative growth, some double or high order pre mutants exhibited defective floral development, resulting in reduced fertility. While pre2pre5 is normally fertile, both pre2pre6 and pre5pre6 showed reduced fertility. Further, the reduced fertility was exacerbated in the pre2pre5pre6 mutant, indicative of the redundant and critical roles of these PREs. Self-pollination assay and scanning electron microscopy analysis showed that the sterility of pre2pre5pre6 was mainly ascribed to the reduced cell elongation of anther filament, limiting access of pollens to stigma. We found that the expression of a subset of flower-development related genes including ARGOS, IAA19, ACS8, and MYB24 was downregulated in the pre2pre5pre6 flowers. Given these results, we propose that PREs, with unequal functional redundancy, take part in the coordinated growth of floral organs, contributing to successful autogamous reproduction in Arabidopsis thaliana.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Flores/genética , Pólen/genética , Fatores de Transcrição/genética , Arabidopsis/crescimento & desenvolvimento , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/genética , Família Multigênica/genética , Mutação/genética , Pólen/crescimento & desenvolvimento , Polinização/genética , Triazóis/química
10.
Nat Mater ; 16(7): 722-729, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28581481

RESUMO

Charge transfer (CT) is a fundamental and ubiquitous mechanism in biology, physics and chemistry. Here, we evidence that CT dynamics can be altered by multi-layered hyperbolic metamaterial (HMM) substrates. Taking triphenylene:perylene diimide dyad supramolecular self-assemblies as a model system, we reveal longer-lived CT states in the presence of HMM structures, with both charge separation and recombination characteristic times increased by factors of 2.4 and 1.7-that is, relative variations of 140 and 73%, respectively. To rationalize these experimental results in terms of driving force, we successfully introduce image dipole interactions in Marcus theory. The non-local effect herein demonstrated is directly linked to the number of metal-dielectric pairs, can be formalized in the dielectric permittivity, and is presented as a solid analogue to local solvent polarity effects. This model and extra PH3T:PC60BM results show the generality of this non-local phenomenon and that a wide range of kinetic tailoring opportunities can arise from substrate engineering. This work paves the way toward the design of artificial substrates to control CT dynamics of interest for applications in optoelectronics and chemistry.

11.
J Nat Prod ; 81(12): 2647-2653, 2018 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-30540183

RESUMO

A concise synthesis of sericetin (1) was performed in four steps from readily available 3- O-benzylgalangin (4), featuring electrocyclization to produce the tricyclic core and a sequential aromatic Claisen/Cope rearrangement to incorporate the 8-prenyl group of 1. In addition, the therapeutic potential of sericetin (1), isosericetin (2), and three prenylated tetracyclic synthetic intermediates (11, 12, and 14) against cisplatin-induced nephrotoxicity using renal tubular cells were evaluated. Compound 14 showed therapeutic potential against cisplatin-induced kidney damage.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Piranos/farmacologia , Injúria Renal Aguda/induzido quimicamente , Animais , Linhagem Celular , Cisplatino , Fabaceae/química , Estrutura Molecular , Substâncias Protetoras/síntese química , Substâncias Protetoras/uso terapêutico , Piranos/uso terapêutico , Ratos , Ratos Sprague-Dawley
12.
Org Biomol Chem ; 14(4): 1311-24, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26660280

RESUMO

Hemicurcuminoids are based on half of the π-conjugated backbone of curcuminoids. The synthesis of a series of such systems and their borondifluoride complexes is described. The electrochemical and photophysical properties of difluorodioxaborine species were investigated as a function of the nature of electron donor and acceptor groups appended at either terminal positions of the molecular backbone. The emissive character of these dipolar dyes was attributed to an intraligand charge transfer process, leading to fluorescence emission that is strongly dependent on solvent polarity. Quasi-quantitative quenching of fluorescence in high polarity solvents was attributed to photoinduced electron transfer. These dyes were shown to behave as versatile fluorophores. Indeed, they display efficient two-photon excited fluorescence emission leading to high two-photon brightness values. Furthermore, they form nanoparticles in water whose fluorescence emission quantum yield is less than that of the dye in solution, owing to aggregation-induced fluorescence quenching. When cos7 living cells were exposed to these weakly-emitting nanoparticles, one- and two-photon excited fluorescence spectra showed a strong emission within the cytoplasm that originated from the individual molecules. Dye uptake thus involved a disaggregation mechanism at the cell membrane which restored fluorescence emission. This off-on fluorescence switching allows a selective optical monitoring of those molecules that do enter the cell, which offers improved sensitivity and selectivity of detection for bioimaging purposes.


Assuntos
Curcumina/análogos & derivados , Curcumina/análise , Corantes Fluorescentes/análise , Corantes Fluorescentes/síntese química , Hidrocarbonetos Halogenados/análise , Hidrocarbonetos Halogenados/química , Imagem Molecular/métodos , Animais , Células COS , Membrana Celular/química , Membrana Celular/metabolismo , Chlorocebus aethiops , Curcumina/química , Citoplasma/química , Fluorescência , Corantes Fluorescentes/química , Hidrocarbonetos Halogenados/síntese química , Estrutura Molecular , Nanopartículas/química , Fótons , Espectrometria de Fluorescência
13.
Biol Pharm Bull ; 39(5): 728-36, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27150144

RESUMO

Dendropanax morbifera LEVEILLE (DP) has been used in traditional Korean medicines to treat a variety of inflammatory diseases. Although the in vitro anti-inflammatory potential of this plant is understood, its in vivo efficacy and underlying molecular mechanism of anti-inflammatory effects are largely unknown. We elucidated the anti-inflammatory and analgesic activities and the underlying molecular mechanisms of DP using in vitro and in vivo models. Lipopolysaccharide (LPS)-stimulated murine macrophages were used to analyze the in vitro anti-inflammatory potential of DP extract and to elucidate the underlying mechanisms. In vivo animal models of phorbol 12-myristate 13-acetate (TPA)-induced ear edema and acetic acid-induced writhing response tests were used to analyze the in vivo anti-inflammatory effects and anti-nociceptive effects of DP extract, respectively. Methanolic extract of DP (DPME) significantly inhibited the release of nitric oxide (NO) and prostaglandin E2 (PGE2) in LPS-activated macrophages. Among the five sub-fractions, the chloroform fraction (DP-C) showed the most potent suppressive effects against pro-inflammatory mediators and cytokines in LPS-stimulated macrophages. These effects were attributed to inhibition of nuclear factor-κB (NF-κB) nuclear translocation and c-Jun N terminal kinase (JNK) 1/2 phosphorylation and to activation of NF-E2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) signaling. DP-C exhibited strong protective in vivo effects in TPA-induced ear edema mouse model and acetic acid-induced writhing response test. Our data suggest that DP-C has potent anti-inflammatory and analgesic activities and may be a promising treatment against a variety of inflammatory diseases.


Assuntos
Analgésicos , Anti-Inflamatórios , Araliaceae , Heme Oxigenase-1/metabolismo , Proteínas de Membrana/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Extratos Vegetais , Ácido Acético , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Clorofórmio/química , Citocinas/metabolismo , Dinoprostona/metabolismo , Orelha/patologia , Edema/induzido quimicamente , Edema/tratamento farmacológico , MAP Quinase Quinase 4/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , NF-kappa B/metabolismo , Nitritos/metabolismo , Dor/induzido quimicamente , Dor/tratamento farmacológico , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Folhas de Planta , Células RAW 264.7 , Solventes/química , Acetato de Tetradecanoilforbol
14.
Toxicol Appl Pharmacol ; 283(2): 147-55, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25617811

RESUMO

Allergic contact dermatitis (ACD) is a cell-mediated immune response that involves skin sensitization in response to contact with various allergens. Angiogenesis and lymphangiogenesis both play roles in the allergic sensitization process. Epidermal keratinocytes can produce vascular endothelial growth factor (VEGF) in response to UV irradiation and during wound healing. However, the effect of haptenic chemical allergens on the VEGF production of human keratinocytes, which is the primary contact site of toxic allergens, has not been thoroughly researched. We systematically investigated whether immune-regulatory cytokines and chemical allergens would lead to the production of VEGF in normal human keratinocytes (NHKs) in culture. VEGF production significantly increased when NHKs were treated with IFNγ, IL-1α, IL-4, IL-6, IL-17A, IL-22 or TNFα. Among the human sensitizers listed in the OECD Test Guideline (TG) 429, we found that CMI/MI, DNCB, 4-phenylenediamine, cobalt chloride, 2-mercaptobenzothiazole, citral, HCA, cinnamic alcohol, imidazolidinyl urea and nickel chloride all significantly upregulated VEGF production in NHKs. In addition, common human haptenic allergens such as avobenzone, formaldehyde and urushiol, also induced the keratinocyte-derived VEGF production. VEGF upregulation by pro-inflammatory stimuli, IFNγ, DNCB or formaldehyde is preceded by the production of IL-8, an acute inflammatory phase cytokine. Lymphangiogenic VEGF-C gene transcription was significantly increased when NHKs were treated with formaldehyde, DNCB or urushiol, while transcription of VEGF-A and VEGF-B did not change. Therefore, the chemical allergen-induced VEGF upregulation is mainly due to the increase in lymphangiogenic VEGF-C transcription in NHKs. These results suggest that keratinocyte-derived VEGF may regulate the lymphangiogenic process during the skin sensitization process of ACD.


Assuntos
Alérgenos/farmacologia , Epiderme/metabolismo , Queratinócitos/metabolismo , Linfangiogênese/fisiologia , Fator A de Crescimento do Endotélio Vascular/biossíntese , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Epiderme/efeitos dos fármacos , Epiderme/imunologia , Prepúcio do Pênis/efeitos dos fármacos , Prepúcio do Pênis/imunologia , Prepúcio do Pênis/metabolismo , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/imunologia , Linfangiogênese/efeitos dos fármacos , Masculino , Camundongos
15.
J Phys Chem A ; 119(24): 6283-95, 2015 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-26020582

RESUMO

Controlling photoinduced intramolecular charge transfer at the molecular scale is key to the development of molecular devices for nanooptoelectronics. Here, we describe the design, synthesis, electronic characterization, and photophysical properties of two electron donor-acceptor molecular systems that consist of tolane and BF2-containing curcuminoid chromophoric subunits connected in a T-shaped arrangement. The two π-conjugated segments intersect at the electron acceptor dioxaborine core. From steady-state electronic absorption and fluorescence emission, we find that the photophysics of the dialkylamino-substituted analogue is governed by the occurrence of two closely lying excited states. From DFT calculations, we show that excitation in either of these two states results in a distinct shift of the electron density, whether it occurs along the curcuminoid or tolane moiety. Femtosecond transient absorption spectroscopy confirmed these findings. As a consequence, the nature of the emitting state and the photophysical properties are strongly dependent on solvent polarity. Moreover, these characteristics can also be switched by protonation or complexation at the nitrogen atom of the amino group. These features set new approaches toward the construction of a three-terminal molecular system in which the lateral branch would transduce a change of electronic state and ultimately control charge transport in a molecular-scale device.

16.
Kidney Blood Press Res ; 40(1): 1-12, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25661683

RESUMO

BACKGROUND/AIMS: Drug-induced acute kidney injury (AKI) has been a severe threat to hospitalized patients, raising the urgent needs to develop strategies to reduce AKI. We investigated the protective activity of Dendropanax morbifera (DP), a medicinal plant which has been widely used to treat infectious and pain diseases, on acute kidney injury (AKI) using cisplatin-induced nephropathic models. METHODS: Both in vitro renal tubular cells (NRK-52E) and in vivo rat models were used to demonstrate the nephroprotective effect of DP. RESULTS: Methanolic extract from DP significantly reduced cisplatin-induced toxicity in renal tubular cells. Through successive liquid extraction, the extract of DP was separated into n-hexane, CHCl3, EtOAc, n-BuOH, and H2O fractions. Among these, the CHCl3 fraction (DPCF) was found to be most potent. The protective activity of DPCF was found to be mediated through anti-oxidant, mitochondrial protective, and anti-apoptotic activities. In in vivo rat models of AKI, treatment with DPCF significantly reversed the cisplatin-induced increase in blood urea nitrogen and serum creatinine and histopathologic damage, recovered the level of anti-oxidant enzymes, and inhibited renal apoptosis. CONCLUSION: We demonstrated that DP extracts decreased cisplatin-induced renal toxicity, indicating its potential to ameliorate drug-associated acute kidney damage.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/prevenção & controle , Araliaceae , Cisplatino/toxicidade , Extratos Vegetais/uso terapêutico , Injúria Renal Aguda/patologia , Animais , Linhagem Celular , Masculino , Extratos Vegetais/isolamento & purificação , Folhas de Planta , Ratos , Ratos Sprague-Dawley
17.
Stroke ; 45(8): 2438-2443, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24938837

RESUMO

BACKGROUND AND PURPOSE: Despite the rapidly increasing global burden of ischemic stroke, no therapeutic options for neuroprotection against stroke currently exist. Recent studies have shown that autophagy plays a key role in ischemic neuronal death, and treatments that target autophagy may represent a novel strategy in neuroprotection. We investigated whether autophagy is regulated by carnosine, an endogenous pleiotropic dipeptide that has robust neuroprotective activity against ischemic brain damage. METHODS: We examined the effect of carnosine on mitochondrial dysfunction and autophagic processes in rat focal ischemia and in neuronal cultures. RESULTS: Autophagic pathways such as reduction of phosphorylated mammalian target of rapamycin (mTOR)/p70S6K and the conversion of microtubule-associated protein 1 light chain 3 (LC3)-I to LC3-II were enhanced in the ischemic brain. However, treatment with carnosine significantly attenuated autophagic signaling in the ischemic brain, with improvement of brain mitochondrial function and mitophagy signaling. The protective effect of carnosine against autophagy was also confirmed in primary cortical neurons. CONCLUSIONS: Taken together, our data suggest that the neuroprotective effect of carnosine is at least partially mediated by mitochondrial protection and attenuation of deleterious autophagic processes. Our findings shed new light on the mechanistic pathways that this exciting neuroprotective agent influences.


Assuntos
Autofagia/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Carnosina/uso terapêutico , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Isquemia Encefálica/metabolismo , Carnosina/farmacologia , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Acidente Vascular Cerebral/metabolismo , Serina-Treonina Quinases TOR/metabolismo
18.
Bioorg Med Chem Lett ; 24(1): 209-13, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24332495

RESUMO

Next-generation sequencing (NGS) technologies recently developed are now used for study of genomes from various organisms. Sequencing-by-synthesis (SBS) is a key strategy in the NGS. The SBS uses nucleotides so-called dual-modified reversible terminators (DRTs) in which bases are labeled with fluorophores and 3'-OH is protected with a reversibly cleavable chemical group, respectively. In this study, we examined the possibility of performing SBS with mono-modified reversible terminators (MRTs), in which the reversible blocking group on the 3'-OH plays a dual role as a fluorescent signal report as well as a chemical protection. We studied cyclic reversible termination by using two MRTs (dA and dT), wherein the modifications were two different fluorophores and cleavable to regenerate a free 3'-OH. We here demonstrated that SBS could be achieved with incorporation of MRTs by a DNA polymerase and correct base-calls based on the two different colors from the fluorophores.


Assuntos
Nucleotídeos/síntese química , Estrutura Molecular , Nucleotídeos/química , Análise de Sequência de DNA
19.
Biol Pharm Bull ; 37(7): 1248-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24989016

RESUMO

Cardiovascular complications are the major causes of death in patients with diabetes mellitus. Several studies have demonstrated that endothelial progenitor cells (EPCs), adult stem cells contributing to the regeneration of vascular endothelium, are dysfunctional under diabetic condition resulting in impaired peripheral circulation and delayed wound healing. In this study, we investigated the cellular alteration of EPCs under high glucose condition, to elucidate the mechanisms underlying diabetes-associated EPC dysfunction. EPCs were isolated from bone marrow and cultured in normal glucose (5.5 mM)- or high glucose (HG; 30 mM)-containing medium. High glucose treated-EPCs showed decreased ability to form tubule-like networks in Matrigel compared to EPCs under normal glucose, which matched well to the clinical observation of diabetic EPC dysfunction. Conversion of LC3-I to LC3-II was increased in EPCs under HG condition, showing that HG induced autophagy in EPCs. Flow cytometric analysis revealed generation of oxidative stress and disruption of mitochondrial permeability in HG exposed EPCs. Increased mitochondrial oxidative stress was also observed by mitochondria-specific superoxide indicator, MitoSOX(TM). Taken together, we demonstrated that autophagy and mitochondrial impairment were induced in EPCs under high glucose condition, giving a new insight into the mechanism underlying dysfunction of diabetic EPCs. We hope that our finding can contribute to the development of a new treatment option for cardiovascular complications in diabetic patients.


Assuntos
Autofagia/efeitos dos fármacos , Células Progenitoras Endoteliais/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Glucose/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Animais , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/patologia , Técnicas de Cultura de Células , Células Cultivadas , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patologia , Relação Dose-Resposta a Droga , Células Progenitoras Endoteliais/metabolismo , Células Progenitoras Endoteliais/patologia , Endotélio Vascular/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
20.
Front Microbiol ; 15: 1361961, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38784813

RESUMO

Introduction: The white-spotted flower chafer (Protaetia brevitarsis seulensis), which is widely distributed in Asian countries, is traditionally used in oriental medicine. However, its larvae are prone to severe damage by green muscardine disease (caused by Metarhizium anisopliae) during breeding. The aim of this study was to characterize Bacillus velezensis TJS119, which has been isolated from freshwater, and investigate its potential as a biocontrol agent against M. anisopliae in insects. Methods: TJS119 was obtained from freshwater samples in the Republic of Korea and was classified as B. velezensis. We evaluated its in vitro antifungal effect, sequenced the bacterial whole genome, mined genes responsible for the synthesis of secondary metabolites, performed secondary metabolite analysis Ultra performance liquid chromatography-mass spectrometry (UPLC-MS/MS), and conducted bioassays for determining green muscardine disease control ability. Results: Bacillus velezensis TJS119 inhibited the mycelial growth of M. anisopliae in vitro. The size of the B. velezensis TJS119 genome was estimated to be 3,890,913 bp with a GC content of 46.67% and 3,750 coding sequences. Biosynthetic gene clusters for secondary metabolites with antifungal activity were identified in the genome. Lipopeptides, including fengycin secreted by TJS119 exhibit antifungal activity. Application of TJS119 for the biocontrol against green muscardine disease increased the viability of white-spotted flower chafer by 94.7% compared to the control. Discussion: These results indicate that B. velezensis TJS119 is a potential biocontrol agent for insect pathogens.

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