RESUMO
BACKGROUND: In chronic myelogenous leukemia, reciprocal translocation between chromosome 9 and chromosome 22 generates a chimeric protein, Bcr-Abl, that leads to hyperactivity of tyrosine kinase-linked signaling transduction. The therapeutic agent nilotinib inhibits Bcr-Abl/DDR1 and can cross the blood-brain barrier, but its potential impact on neuroinflammatory responses and cognitive function has not been studied in detail. METHODS: The effects of nilotinib in vitro and in vivo were assessed by a combination of RT-PCR, real-time PCR, western blotting, ELISA, immunostaining, and/or subcellular fractionation. In the in vitro experiments, the effects of 200 ng/mL LPS or PBS on BV2 microglial cells, primary microglia or primary astrocytes pre- or post-treated with 5 µM nilotinib or vehicle were evaluated. The in vivo experiments involved wild-type mice administered a 7-day course of daily injections with 20 mg/kg nilotinib (i.p.) or vehicle before injection with 10 mg/kg LPS (i.p.) or PBS. RESULTS: In BV2 microglial cells, pre- and post-treatment with nilotinib altered LPS-induced proinflammatory/anti-inflammatory cytokine mRNA levels by suppressing AKT/P38/SOD2 signaling. Nilotinib treatment also significantly downregulated LPS-stimulated proinflammatory cytokine levels in primary microglia and primary astrocytes by altering P38/STAT3 signaling. Experiments in wild-type mice showed that nilotinib administration affected LPS-mediated microglial/astroglial activation in a brain region-specific manner in vivo. In addition, nilotinib significantly reduced proinflammatory cytokine IL-1ß, IL-6 and COX-2 levels and P38/STAT3 signaling in the brain in LPS-treated wild-type mice. Importantly, nilotinib treatment rescued LPS-mediated spatial working memory impairment and cortical dendritic spine number in wild-type mice. CONCLUSIONS: Our results indicate that nilotinib can modulate neuroinflammatory responses and cognitive function in LPS-stimulated wild-type mice.
Assuntos
Disfunção Cognitiva , Lipopolissacarídeos , Sistema de Sinalização das MAP Quinases , Pirimidinas , Fator de Transcrição STAT3 , Animais , Disfunção Cognitiva/metabolismo , Citocinas/metabolismo , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Microglia/metabolismo , Pirimidinas/farmacologia , Fator de Transcrição STAT3/metabolismoRESUMO
The cholinesterase inhibitor donepezil is used to improve Aß pathology and cognitive function in patients with Alzheimer's disease (AD). However, the impact of donepezil on tau pathology is unclear. Thus, we examined the effects of donepezil on Aß and tau pathology in 5xFAD mice (a model of AD) in this study. We found that intraperitoneal injection of donepezil (1 mg/kg, i.p.) exhibited significant reductions in Aß plaque number in the cortex and hippocampal DG region. In addition, donepezil treatment (1 mg/kg, i.p.) reduced Aß-mediated microglial and, to a lesser extent, astrocytic activation in 5xFAD mice. However, neither intraperitoneal/oral injection of donepezil nor oral injection of rivastigmine altered tau phosphorylation at Thr212/Ser214 (AT100), Thr396, and Thr231 in 5xFAD mice. Surprisingly, we observed that intraperitoneal/oral injection of donepezil treatment significantly increased tau phosphorylation at Thr212 in 5xFAD mice. Taken together, these data suggest that intraperitoneal injection of donepezil suppresses Aß pathology but not tau pathology in 5xFAD mice.
Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Animais , Modelos Animais de Doenças , Donepezila/farmacologia , Donepezila/uso terapêutico , Camundongos , Camundongos Transgênicos , Placa AmiloideRESUMO
Thymic stromal lymphopoietin (TSLP), a master switch of allergic inflammation, plays an important role in the pathogenesis of allergic diseases. Although many compounds upregulate TSLP expression in vivo or in vitro, most of them are pollutants or toxicants. In the previous study, for the first time, we found that a steroid alkaloid derivative 02F04, which has a unique skeletal structure compared with other TSLP-inducing chemicals, significantly induced TSLP production in mouse keratinocytes. However, it is not investigated thoroughly that how 02F04 produces TSLP and why. In this study, we did a detailed investigation on the inducible effect and underlying molecular mechanism of 02F04 on TSLP production. We found that the peak time of TSLP mRNA level induced by 02F04 at 48â¯h led to a slow and continuous TSLP production in PAM212 cells. Besides, 02F04-induced TSLP production was significantly suppressed by inhibitors of Rho-associated protein kinase (ROCK), guanine nucleotide-binding protein subunit alpha q/11 (Gq/11) and extracellular signal-regulated kinase 1/2 (ERK1/2) at not only protein but also mRNA levels, and by siRNA-mediated knockdown of Gq or G11. This suggested that ROCK, Gq/11 and ERK1/2 signaling pathways were involved in 02F04-induced TSLP production. Increase in the level of p-ERK1/2 induced by 02F04 was suppressed by both inhibitors of ROCK and Gq/11, indicating that ROCK and Gq/11 molecules were located at the upstream of ERK1/2 to regulate 02F04-induced TSLP production. Gq/11 was located at the upstream of ROCK because the specific Gq/11 inhibitor of YM-254890 significantly reduced 02F04-induced actin stress fiber formation. Taken together, 02F04 upregulates a slow and continuous TSLP production through a novel Gq/11-ROCK-ERK1/2 signaling pathway. The thorough understanding the effect and mechanism of 02F04 on TSLP production is expected to supply it as a novel TSLP-regulating compound and a potential new tool for investigating the role of TSLP in allergic disorders.
Assuntos
Alcaloides/farmacologia , Citocinas/metabolismo , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Alcaloides/química , Animais , Células Cultivadas , Citocinas/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Linfopoietina do Estroma do TimoRESUMO
BACKGROUND: Epimagnolin A is an ingredient of the Chinese crude drug Shin-i, derived from the dried flower buds of Magnolia fargesii and Magnolia flos, which has been traditionally used for the treatment of allergic rhinitis and nasal congestion, empyema, and sinusitis. The pharmacokinetic activity of epimagnolin A remains to be evaluated. PURPOSE: In this study, we examined the possible interactions of epimagnolin A with human ATP-binding cassette (ABC) transporter ABCB1, a membrane protein vital in regulating the pharmacokinetics of drugs and xenobiotics. STUDY DESIGN/METHODS: The interaction of epimagnolin A with ABCB1 was evaluated in calcein, ATPase, and MTT assays by using Flp-In-293/ABCB1 cells and purified ABCB1 and simulated in molecular docking studies. RESULTS: Epimagnolin A inhibited calcein export by Flp-In-293/ABCB1 cells in a concentration-dependent manner in a calcein assay. ATPase assay revealed a concentration-dependent stimulation of the ATPase activity of ABCB1 by epimagnolin A. Epimagnolin A also showed saturation kinetics in the relationship between the compound-stimulated ATPase activity and the compound concentration, suggesting Michaelis-Menten kinetics similar to those of the control drug, verapamil. Km and Vmax values were calculated from Hanes-Woolf plots of (compound concentration)â¯×â¯(compound-stimulated ATPase activity)-1â¯vs. (compound concentration); the Km of epimagnolin and verapamil was 42.9⯱â¯7.53 ⯵M and 12.3⯱â¯4.79⯠µM, respectively, and the corresponding Vmax values were 156⯱â¯15.0⯠µM and 109⯱â¯3.18⯠µM. Molecular docking studies on human ABCB1 showed that epimagnolin A docked to the same binding pocket as verapamil, and 3-(4,5-dimethyl-2-thiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assays showed that the sensitivities of Flp-In-293/ABCB1 cells against anti-cancer drugs were enhanced upon exposure to 10⯠µM epimagnolin A. CONCLUSION: These results strongly suggest that epimagnolin A affects the transport activity of ABCB1 as a substrate.
Assuntos
Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Lignanas/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Adenosina Trifosfatases/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Humanos , Magnolia/química , Simulação de Acoplamento Molecular , Verapamil/farmacologiaRESUMO
Thymic stromal lymphopoietin (TSLP) plays critical roles in inducing and exacerbating allergic diseases. Chemical compounds that induce TSLP production can enhance sensitization to antigens and exacerbate allergic inflammation. Hence, identifying such chemicals will be important to prevent an increase in allergic diseases. In the present study, we found, for the first time, that a steroid alkaloid derivative, code no. 02F04, concentration and time dependently induced mRNA expression and production of TSLP in a mouse keratinocyte cell line, PAM212. In particular, the activity of 02F04 was selective to TSLP. As an analogue of the liver X receptor (LXR) endogenous ligand, 02F04 rapidly increased ATP-binding cassette transporter A1 (ABCA1) expression by regulating the nuclear receptor of LXR. However, instead of being inhibited by the LXR antagonist, 02F04-induced TSLP production was delayed and markedly suppressed by inhibitors of phospholipase C (PLC), pan-protein kinase C (PKC), PKCδ, Rho-associated protein kinase (ROCK), extracellular signal-regulated kinase (ERK) 1/2, and IκΒ kinase 2 (IKK2). Treatment with 02F04 caused the formation of F-actin filaments surrounding the nucleus of PAM212 cells, which then disappeared following addition of ROCK inhibitor. 02F04 also induced phosphorylation of ERK1/2 from 2h after treatment, with a maximum at 24h, and increased nuclear factor-κB (NF-κB) promoter activity by 1.3-fold. Taken together, these results indicate that 02F04-induced TSLP production is regulated via distinct signal transduction pathways, including PLC, PKC, ROCK, ERK1/2, and NF-κB but not nuclear receptors. 02F04, with a unique skeletal structure in inducing TSLP production, can represent a potential new tool for investigating the role of TSLP in allergic diseases.
Assuntos
Alcaloides/farmacologia , Citocinas/metabolismo , Hipersensibilidade/metabolismo , Queratinócitos/fisiologia , Esteroides/farmacologia , Alcaloides/química , Animais , Linhagem Celular , Citocinas/genética , Regulação da Expressão Gênica , Queratinócitos/efeitos dos fármacos , Receptores X do Fígado/química , Sistema de Sinalização das MAP Quinases , Camundongos , Fosforilação , Proteína Quinase C/metabolismo , Esteroides/química , Fosfolipases Tipo C/metabolismo , Linfopoietina do Estroma do TimoRESUMO
Oxidative stress contributes to neuronal death in the brain, and neuronal death can cause aging or neurodegenerative disease. Heme oxygenase 1 (HO-1) serves a vital role in the regulation of biological reactions, including oxidative stress associated with reactive oxygen species. In the present study, acerogenin C isolated from the Aceraceae plant Acer nikoense, which is used as a Japanese folk medicine for hepatic disorders and eye diseases. However, there have been no studies on the mechanisms underlying the antineurodegenerative biological activities of acerogenin C. In the present study, acerogenin C demonstrated neuroprotective action against glutamateinduced cell death in hippocampal HT22 cells through the upregulation of HO1 expression. These effects were also associated with nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and the activation of phosphoinositide 3kinase/protein kinase B. Taken together of the efficacy researches, this study determines that the Nrf2/HO1 pathways denotes a biological mark and that acerogenin C might contribute to prevention of neurodegenerative disorders.
Assuntos
Acer/química , Heme Oxigenase-1/metabolismo , Hipocampo/citologia , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/farmacologia , Éteres Fenílicos/farmacologia , Regulação para Cima/efeitos dos fármacos , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Ácido Glutâmico/toxicidade , Heme Oxigenase-1/genética , Camundongos , Fármacos Neuroprotetores/química , Éteres Fenílicos/química , Fosfatidilinositol 3-Quinases/metabolismo , Transporte Proteico/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Acorn (Quercus acutissima CARR.) is a nut from the Fagaceae family that has been used in traditional medicine for many years. However, shells from acorns are regarded as a by-product and are mostly discarded. Anti-adipogenic activities of acorn shells were investigated using 3T3-L1 cells and methanol shell extracts (AE-M). AE-M demonstrated Cu2+-chelation activities and anti-oxidant activities via reduction of oxidative stress levels induced using AAPH. Six days after adipocyte differentiation, 50 and 100 µg/mL AE-M completely suppressed 3T3-L1 adipogenesis and the anti-adipogenic effect was stronger than for the positive control 50 µM quercetin. Treatment with AE-M in 3T3-L1 cells reduced mRNA expression levels of adipogenic genes. AE-M-inhibition was found in pre-adipogenic, early, and intermediate stages of adipogenesis in 3T3-L1 cells. The Wnt/ß-catenin signaling pathway is required for AE-M-inhibition of 3T3-L1 adipogenesis.
RESUMO
Oxidative cell damage contributes to neuronal degeneration in many central nervous system (CNS) diseases such as Parkinson's disease, Alzheimer's disease, and ischemia. Inducible heme oxygenase (HO)-1 acts against oxidants that are thought to play a key role in the pathogenesis of neuronal diseases. The stem bark of Acer nikoense Maxim (Aceraceae) is indigenous to Japan; it has been used in folk medicine as a treatment of hepatic disorders and eye diseases. Acerogenin A, a natural compound isolated from Japanese folk medicine A. nikoense, showed neuroprotective effects and reactive oxygen species (ROS) reduction on glutamate-induced neurotoxicity by inducing the expression of HO-1 in mouse hippocampal HT22 cells. Furthermore, acerogenin A caused the nuclear accumulation of nuclear factor-E2-related factor 2 (Nrf2) and the activation of the PI3K/AKT signaling pathways. In this study, we demonstrated that acerogenin A effectively prevents glutamate-induced oxidative damage, and HO-1 induction via PI3K/Akt and Nrf2 pathways appears to play a key role in the protection of HT22 cells. Therefore, this study implies that the Nrf2/HO-1 pathway represents a biological target and that acerogenin A might be a candidate for the prevention of neurodegeneration.
Assuntos
Diarileptanoides/farmacologia , Heme Oxigenase-1/genética , Hipocampo/efeitos dos fármacos , Proteínas de Membrana/genética , Fator 2 Relacionado a NF-E2/genética , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Éteres Fenílicos/farmacologia , Animais , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Citosol/efeitos dos fármacos , Citosol/metabolismo , Diarileptanoides/isolamento & purificação , Regulação da Expressão Gênica , Ácido Glutâmico/toxicidade , Heme Oxigenase-1/metabolismo , Hipocampo/citologia , Hipocampo/metabolismo , Proteínas de Membrana/agonistas , Proteínas de Membrana/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Fármacos Neuroprotetores/isolamento & purificação , Estresse Oxidativo/efeitos dos fármacos , Éteres Fenílicos/isolamento & purificação , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Casca de Planta/química , Extratos Vegetais/química , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Transdução de SinaisRESUMO
Methyl 3,5-di-caffeoylquinate (3,5-diCQM) has been used for the treatment of various diseases in oriental medicine, but its effect on melanogenesis has not been reported yet. In this study, the molecular mechanism of 3,5-diCQM-induced melanogenesis was investigated. It was found that 3,5-diCQM induced synthesis of melanin pigments in murine B16F10 melanoma cells in a concentration-dependent manner. Treatment of cells with 3,5-diCQM for 48 h increased extracellular and intracellular melanin production and tyrosinase activity. The expressions of tyrosinase, tyrosinase-related protein 1 (TRP1), and TRP2 were up-regulated in a dose-dependent manner 48 h after 3,5-diCQM treatment. Western blot analysis showed that 3,5-diCQM increased the phosphorylation of p38 mitogen-activated protein kinase and cAMP responsive element binding as well as the expression of microphthalmia-associated transcription factor. In addition, 3,5-diCQM-stimulated cAMP production, and 3,5-diCQM-induced tyrosinase activity and melanin synthesis were attenuated by H89, a protein kinase A inhibitor. These results suggested that 3,5-diCQM-mediated activation of the p38 pathway may represent a novel approach for an effective therapy for vitiligo and hair graying.
Assuntos
Ácidos Cafeicos/farmacologia , Fator de Transcrição Associado à Microftalmia/fisiologia , Monofenol Mono-Oxigenase/biossíntese , Transtornos da Pigmentação/induzido quimicamente , Ácido Quínico/análogos & derivados , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Linhagem Celular Tumoral , Ácido Clorogênico/análogos & derivados , Ativação Enzimática , Indução Enzimática , Camundongos , Ácido Quínico/farmacologiaRESUMO
The melanin-inducing properties of cirsimaritin were investigated in murine B16F10 cells. Cirsimaritin is an active flavone with methoxy groups, which is isolated from the branches of Lithocarpus dealbatus. Tyrosinase activity and melanin content in murine B16F10 melanoma cells were increased by cirsimaritin in a dose-dependent manner. Western blot analysis revealed that tyrosinase, tyrosinase-related protein (TRP) 1, TRP2 protein levels were enhanced after treatment with cirsimaritin for 48 h. Cirsimaritin also upregulated the expression of microphthalmia-associated transcription factor (MITF) after 24 h of treatment. Furthermore, cirsimaritin induced phosphorylation of cyclic adenosine monophosphate (cAMP) response element-binding protein (CREB) in a dose-dependent manner after treatment for 15 min. The cirsimaritin-mediated increase of tyrosinase activity was significantly attenuated by H89, a cAMP-dependent protein kinase A inhibitor. These findings indicate that cirsimaritin stimulates melanogenesis in B16F10 cells by activation of CREB as well as upregulation of MITF and tyrosinase expression, which was activated by cAMP signaling. Finally, the melanogenic effect of cirsimaritin was confirmed in human epidermal melanocytes. These results support the putative application of cirsimaritin in ultraviolet photoprotection and hair coloration treatments.
Assuntos
Flavonas/farmacologia , Melaninas/biossíntese , Animais , Sobrevivência Celular , AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Humanos , Oxirredutases Intramoleculares/metabolismo , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Melanoma Experimental , Glicoproteínas de Membrana/metabolismo , Camundongos , Fator de Transcrição Associado à Microftalmia/metabolismo , Monofenol Mono-Oxigenase , Oxirredutases/metabolismo , Fosforilação , Processamento de Proteína Pós-Traducional , Sistemas do Segundo Mensageiro , Regulação para Cima/efeitos dos fármacosRESUMO
SCOPE: Bone homeostasis is ensured by the balance between bone formation and resorption. Thus, control of the recruitment, proliferation, and differentiation of bone cells is essential to maintain bone mass. The aim of this study was to elucidate the effects of rosmarinic acid as a potential therapeutic agent on bone metabolism using bone cells and a mouse model. METHODS AND RESULTS: Rosmarinic acid increased alkaline phosphatase activity and induced mineralization in osteoblasts. Addition of rosmarinic acid to cultures of calvarial osteoblastic cells prepared from T-cell factor/ß-catenin TOP-GAL mutant mice strongly induced the expression of LacZ and promoted stabilization of ß-catenin in the cytoplasm of ST2 cells, suggesting that rosmarinic acid affects the canonical Wnt signaling pathway. Moreover, rosmarinic acid inhibited not only osteoclast formation in cocultures of mouse bone marrow cells and osteoblasts, but also receptor activator of nuclear factor kappa-B ligand (RANKL)-induced osteoclastic differentiation in bone marrow-derived macrophages. RANKL-induced p38 mitogen-activated protein kinase and the expression of nuclear factor of activated T cell, c-Jun, and c-Fos were inhibited by rosmarinic acid in bone marrow macrophages. Finally, we confirmed that rosmarinic acid improved bone mass in a soluble RANKL-induced bone loss mouse model. CONCLUSION: Rosmarinic acid has dual regulatory effects on bone metabolism and may control the bone functions by controlling osteoblastic and osteoclastic differentiation.
Assuntos
Reabsorção Óssea/tratamento farmacológico , Cinamatos/farmacologia , Depsídeos/farmacologia , Osteoblastos/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Animais , Densidade Óssea/efeitos dos fármacos , Células da Medula Óssea/efeitos dos fármacos , Reabsorção Óssea/induzido quimicamente , Reabsorção Óssea/patologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Modelos Animais de Doenças , Masculino , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Transgênicos , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Ligante RANK/toxicidade , Proteína Wnt3A/genética , Proteína Wnt3A/metabolismo , beta Catenina/metabolismo , Ácido RosmarínicoRESUMO
Nobiletin is a unique flavonoid having polymethoxy groups and has exhibited anti-inflammatory and antiobesity effects. Here, we examined the inhibition of nobiletin on melanogenesis induced by endothelin-1 (ET) and stem cell factor (SCF) in normal human melanocytes. Nobiletin dose dependently reduced ET plus SCF-stimulated tyrosinase activity without causing cytotoxicity. Nobiletin reduced cAMP-response element-binding protein (CREB) phosphorylation and microphthalmia-associated transcription factor (MITF) expression, which is a key transcription factor for tyrosinase expression in pigmentation induced by ET plus SCF stimulation. Nobiletin treatment effectively decreased ET plus SCF-induced Raf-1, MEK and ERK1/2 phosphorylation and also downregulated the forskolin-induced phosphorylation of CREB. Furthermore, nobiletin inhibited ET plus SCF-triggered production of melanin and expression of MITF/tyrosinase in a three-dimensional human epidermal model. In accordance with protein expression, the expression of genes related to the pigmentation was also increased in the cells stimulated with ET plus SCF and the cotreatment with nobiletin decreased obviously the ET plus SCF-triggered gene expressions of tyrosinase, PMEL, TRP1 and MITF. Nobiletin contributes to hypopigmentation by downregulating MITF and tyrosinase expression through reduced Raf-1 phosphorylation. Our findings implicate nobiletin as a potential new whitening agent.
Assuntos
Endotelina-1/antagonistas & inibidores , Flavonas/farmacologia , Melaninas/antagonistas & inibidores , Melanócitos/efeitos dos fármacos , Preparações Clareadoras de Pele/farmacologia , Fator de Células-Tronco/antagonistas & inibidores , Células Cultivadas , Colforsina/farmacologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Endotelina-1/farmacologia , Regulação da Expressão Gênica , Humanos , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/metabolismo , Melaninas/biossíntese , Melanócitos/citologia , Melanócitos/metabolismo , Fator de Transcrição Associado à Microftalmia/genética , Fator de Transcrição Associado à Microftalmia/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Monofenol Mono-Oxigenase/genética , Monofenol Mono-Oxigenase/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-raf/genética , Proteínas Proto-Oncogênicas c-raf/metabolismo , Transdução de Sinais , Fator de Células-Tronco/farmacologia , Técnicas de Cultura de Tecidos , Antígeno gp100 de Melanoma/genética , Antígeno gp100 de Melanoma/metabolismoRESUMO
SCOPE: This study investigated the effect of honokiol (HON) and magnolol (MAG), phenolic compounds in Magnolia plants, on adiposity and adiposity-related metabolic disturbances in mice fed high-fat diet (HFD), and the potential underlying mechanisms focusing on the lipid metabolism and inflammatory response. METHOD AND RESULTS: C57BL/6J mice were fed HFD (45 kcal% fat) with or without HON (0.02%, w/w) or MAG (0.02%, w/w) for 16 wk. Despite no changes in body weight, food intake, and hepatic fat accumulation, HON and MAG significantly lowered the weight of white adipose tissue (WAT) as well as adipocyte size and protected against insulin resistance induced by HFD. These effects were associated with increases in energy expenditure and adipose fatty acid oxidation and decreases in fatty acid synthase activity and expression of genes related to fatty acid synthesis, desaturation, and uptake, as well as adipocyte differentiation in WAT. Moreover, HON and MAG significantly lowered the expression of proinflammatory genes in WAT and elevated the plasma IL-10 level. Particularly, HON significantly decreased the plasma resistin level and increased the plasma adiponectin level compared to the control group. CONCLUSION: HON and MAG have potential as novel agents for amelioration of adiposity and associated insulin resistance and inflammation.
Assuntos
Tecido Adiposo Branco/efeitos dos fármacos , Compostos de Bifenilo/administração & dosagem , Suplementos Nutricionais , Inflamação/tratamento farmacológico , Resistência à Insulina , Lignanas/administração & dosagem , Adipogenia/efeitos dos fármacos , Adiponectina/sangue , Tecido Adiposo Branco/metabolismo , Adiposidade/efeitos dos fármacos , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Quimiocina CCL2/sangue , Colesterol/sangue , Dieta Hiperlipídica , Metabolismo Energético , Teste de Tolerância a Glucose , Interleucina-10/sangue , Interleucina-6/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Triglicerídeos/sangue , Fator de Necrose Tumoral alfa/sangueRESUMO
Using B16 melanoma cells for screening, we found that a marine sponge extract has a potent anti-pigmenting effect and identified arenarol as its major active compound. In normal human melanocytes (NHMs), arenarol significantly abrogated the endothelin 1 (EDN1) stimulated expression of tyrosinase, tyrosinase-related protein 1 and dopachrome tautomerase at the transcriptional, translational and enzymatic activity (only for tyrosinase) levels. That effect was accompanied by the attenuation of the increased expression level of microphthalmia-associated transcription factor (MITF) protein at the transcriptional and translational levels. Analysis of EDN1 signaling demonstrated that arenarol significantly suppressed the EDN1-induced phosphorylation of MEK, ERK, MITF and CREB but not of Raf-1s. In contrast, the forskolin-induced phosphorylation of CREB was not down-regulated by arenarol. As for the mode of action of the suppressed phosphorylation of MEK, Raf-1 activity was not directly inhibited by arenarol in vitro and pretreatment with the protein phosphatase inhibitor okadaic acid did not affect the down-regulated phosphorylation of MEK that was induced by arenarol in NHMs. The sum of these findings suggests that arenarol abrogates the EDN1-stimulated expression of melanocyte-specific proteins by interrupting MEK phosphorylation in an as yet unknown Raf-1 inactivation mechanism.
RESUMO
Platelet-derived growth factor (PDGF) induces the proliferation and migration of vascular smooth muscle cells (VSMCs), leading to the development of various vascular disorders such as restenosis and atherosclerosis. Therefore, inhibitors of PDGF-induced cellular events would be candidate agents for treating these diseases. During the search for such inhibitors from marine sources, we isolated petrosiols A-D (1-4) and related compounds from the marine sponge Petrosia strongylata. These metabolites, which we previously reported as neurotrophic substances, showed an inhibitory effect on PDGF-induced DNA synthesis at IC50 values of 0.69-2.2 µM. Petrosiol A (1) inhibited PDGF-induced cell proliferation without remarkable cytotoxicity and arrested cell cycle progression from the G0/G1 to S phase by inducing the downregulation of the expression of G1 checkpoint proteins cyclin D1, cyclin E, cyclin-dependent kinases (CDK)2, and CDK4 and the upregulation of the expression of p21 and p27. In addition, petrosiol A (1) inhibited the phosphorylation of PDGF receptor-ß and its downstream proteins such as phospholipase C (PLC)-γ1, Akt, and extracellular signal-regulated kinase (ERK)1/2. These results suggest that 1 inhibited PDGF-induced VSMC proliferation by interrupting the phosphorylation of PDGF receptor-ß followed by downstream signal transduction. Furthermore, petrosiol A (1) suppressed PDGF-induced actin filament dissociation and cell migration, suggesting that 1 and its derivatives may be used for the prevention and treatment of vascular diseases.
Assuntos
Álcoois/química , Álcoois/farmacologia , Alcinos/química , Alcinos/farmacologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/metabolismo , Poríferos/química , Actinas/metabolismo , Álcoois/isolamento & purificação , Alcinos/isolamento & purificação , Animais , Aorta/citologia , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , DNA/metabolismo , Humanos , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Liquorice is one of the botanicals used frequently as a traditional medicine in the West and in the East. Platelet-derived growth factor (PDGF)-BB is involved in the development of CVD by inducing abnormal proliferation and migration of vascular smooth muscle cells. In our preliminary study, dehydroglyasperin C (DGC), an active compound of liquorice, showed strong antioxidant activity. Since phytochemicals with antioxidant activities showed beneficial effects on chronic inflammatory diseases, the present study aimed to investigate the effects of DGC on PDGF-induced proliferation and migration of human aortic smooth muscle cells (HASMC). Treatment of HASMC with DGC for 24 h significantly decreased PDGF-induced cell number and DNA synthesis in a dose-dependent manner without any cytotoxicity, as demonstrated by the 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide test and thymidine incorporation. Upon cell cycle analysis, DGC blocked the PDGF-induced progression through the G0/G1 to S phase of the cell cycle, and down-regulated the expression of cyclin-dependent kinase (CDK); 2, cyclin E, CDK4 and cyclin D1. Furthermore, DGC significantly attenuated PDGF-stimulated phosphorylation of PDGF receptor-b, phospholipase C-g1, AKT and extracellular-regulated kinase 1/2, and DGC inhibited cell migration and the dissociation of actin filaments by PDGF. In a rat vascular balloon injury model, DGC suppressed an excessive reduction in luminal diameters and neointimal formation compared with the control group. These results demonstrate the mechanistic basis for the prevention of CVD and the potential therapeutic properties of DGC.
Assuntos
Benzopiranos/farmacologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Glycyrrhiza/química , Músculo Liso Vascular/efeitos dos fármacos , Placa Aterosclerótica , Fator de Crescimento Derivado de Plaquetas/metabolismo , Citoesqueleto de Actina/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Aorta/efeitos dos fármacos , Benzopiranos/uso terapêutico , Ciclo Celular/efeitos dos fármacos , Ciclinas/metabolismo , DNA/biossíntese , Regulação para Baixo , Humanos , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Fosforilação , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Placa Aterosclerótica/genética , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/prevenção & controle , RatosRESUMO
Nobiletin (NOB) is a polymethoxylated flavone present in citrus fruits and has been reported to have antitumor and anti-inflammatory effects. However, little is known about the effects of NOB on obesity and insulin resistance. In this study, we examined the effects of NOB on obesity and insulin resistance, and the underlying mechanisms, in high-fat diet (HFD)-induced obese mice. Obese mice were fed a HFD for 8 weeks and then treated without (HFD control group) or with NOB at 10 or 100mg/kg. NOB decreased body weight gain, white adipose tissue (WAT) weight and plasma triglyceride. Plasma glucose levels tended to decrease compared with the HFD group and improved plasma adiponectin levels and glucose tolerance. Furthermore, NOB altered the expression levels of several lipid metabolism-related and adipokine genes. NOB increased the mRNA expression of peroxisome proliferator-activated receptor (PPAR)-γ, sterol regulatory element-binding protein-1c, fatty acid synthase, stearoyl-CoA desaturase-1, PPAR-α, carnitine palmitoyltransferase-1, uncoupling protein-2 and adiponectin, and decreased the mRNA expression of tumor necrosis factor-α and monocyte chemoattractant protein-1 in WAT. NOB also up-regulated glucose transporter-4 protein expression and Akt phosphorylation and suppressed IκBα degradation in WAT. Taken together, these results suggest that NOB improves adiposity, dyslipidemia, hyperglycemia and insulin resistance. These effects may be elicited by regulating the expression of lipid metabolism-related and adipokine genes, and by regulating the expression of inflammatory makers and activity of the insulin signaling pathway.
Assuntos
Dieta Hiperlipídica/efeitos adversos , Flavonas/farmacologia , Resistência à Insulina , Metabolismo dos Lipídeos/efeitos dos fármacos , Obesidade/tratamento farmacológico , Adipocinas/genética , Adiponectina/genética , Tecido Adiposo Branco/efeitos dos fármacos , Animais , Ingestão de Alimentos/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Insulina/metabolismo , Metabolismo dos Lipídeos/genética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Tamanho do Órgão/efeitos dos fármacos , PPAR gama/genética , Triglicerídeos/sangue , Triglicerídeos/metabolismo , Aumento de Peso/efeitos dos fármacosRESUMO
Flos Magnoliae (FM) is a commonly used Chinese medicinal herb for symptomatic relief of allergic rhinitis, sinusitis and headache. Although several FM species have been used as substitutes or adulterants for clinical use, possible differences in their pharmacological actions have not been reported. To confirm the effects of FM on skeletal muscle glucose metabolism, we tested the effects of several compounds isolated from FM on glucose uptake by L6 myotubes. We found that fargesin, a component of FM, dose-dependently stimulated glucose consumption in L6 myotubes, which was accompanied by enhanced glucose transporter (GLUT)-4 translocation to the cell surface. Fargesin-stimulated glucose uptake was blocked by wortmannin, a phosphatidylinositol-3 kinase (PI3 K) inhibitor. Fargesin stimulated Akt phosphorylation, a key component in the insulin signaling pathway, which was completely inhibited by wortmannin. Here, we demonstrated that fargesin, a bioactive component of Flos Magnoliae, increases basal glucose uptake and GLUT4 translocation in L6 myotubes by activating the PI3 K-Akt pathway.
Assuntos
Benzodioxóis/farmacologia , Transporte Biológico/efeitos dos fármacos , Glucose/metabolismo , Lignanas/farmacologia , Magnolia/química , Mioblastos/efeitos dos fármacos , Mioblastos/metabolismo , Animais , Transportador de Glucose Tipo 4/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacosRESUMO
Leaves develop as flat lateral organs from the indeterminate shoot apical meristem. The establishment of polarity along three-dimensional axes, proximal-distal, medial-lateral, and adaxial-abaxial axes, is crucial for the growth of normal leaves. The mutations of ASYMMETRIC LEAVES1 (AS1) and AS2 of Arabidopsis thaliana cause defects in repression of the indeterminate state and the establishment of axis formation in leaves. Although many mutations have been identified that enhance the adaxial-abaxial polarity defects of as1 and as2 mutants, the roles of the causative genes in leaf development are still unknown. In this study, we found that wild-type plants treated with berberine produced pointed leaves, which are often observed in the single mutants that enhance phenotypes of as1 and as2 mutants. The berberine-treated as1 and as2 mutants formed abaxialized filamentous leaves. Berberine, an isoquinoline alkaloid compound naturally produced in various plant sources, has a growth inhibitory effect on plants that do not produce berberine. We further showed that transcript levels of meristem-specific class 1 KNOX homeobox genes and abaxial determinant genes were increased in berberine-treated as1 and as2. Berberine treated plants carrying double mutations of AS2 and the large subunit ribosomal protein gene RPL5B showed more severe defects in polarity than did the as2 single mutant plants. We suggest that berberine inhibits (a) factor(s) that might be required for leaf adaxial cell differentiation through a pathway independent of AS1 and AS2. Multiple pathways might play important roles in the formation of flat symmetric leaves.
Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Berberina/farmacologia , Folhas de Planta/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Arabidopsis/efeitos dos fármacos , Proteínas de Arabidopsis/genética , Berberina/química , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Mesoporfirinas/farmacologia , Análise em Microsséries , Estrutura Molecular , Fenótipo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Plântula/efeitos dos fármacos , Fatores de Transcrição/genéticaRESUMO
The G-quadruplex is one of the most frequently studied secondary DNA structures and consists of 4 guanine residues that interact through Watson-Crick and Hoogsteen pairing. The G-quadruplex formation is thought to be a molecular switch for gene expression. Genome-wide analyses of G-quadruplexes have been published for many species; however, only one genome-wide analysis of G-quadruplexes in plants has been reported. Here, we propose a new approach involving a two-step procedure for identifying G-quadruplex-forming sequences (potential G4 DNA motif regions: G4MRs) and classifying positional relationships between G4MRs and genes. By using this approach, we exhaustively searched for G4MRs in the whole genomes of 8 species: Arabidopsis thaliana, Oryza sativa subsp. japonica, Populus trichocarpa, Vitis vinifera, Homo sapiens, Danio rerio, Drosophila melanogaster, and Caenorhabditis elegans. We classified genes on the basis of their positional relationships to their proximal G4MRs. We identified novel rules for G4MRs in plants, such as G4MR-enrichment in the template strands at transcription start sites (TSSs). Next, we focused on the template strands of TSSs and conducted gene ontology (GO) analysis of genes proximal to G4MRs. We identified GO terms such as chloroplast and nucleosome (or histone) in O. sativa. Although these terms were strongly associated in O. sativa, weak associations were identified in other plants. These results will be helpful for elucidating the functional roles of G4 DNA.