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1.
Nat Immunol ; 20(10): 1348-1359, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31406382

RESUMO

Helper T cells actively communicate with adjacent cells by secreting soluble mediators, yet crosstalk between helper T cells and endothelial cells remains poorly understood. Here we found that placental growth factor (PlGF), a homolog of the vascular endothelial growth factor that enhances an angiogenic switch in disease, was selectively secreted by the TH17 subset of helper T cells and promoted angiogenesis. Interestingly, the 'angio-lymphokine' PlGF, in turn, specifically induced the differentiation of pathogenic TH17 cells by activating the transcription factor STAT3 via binding to its receptors and replaced the activity of interleukin-6 in the production of interleukin-17, whereas it suppressed the generation of regulatory T cells. Moreover, T cell-derived PlGF was required for the progression of autoimmune diseases associated with TH17 differentiation, including experimental autoimmune encephalomyelitis and collagen-induced arthritis, in mice. Collectively, our findings provide insights into the PlGF-dictated links among angiogenesis, TH17 cell development and autoimmunity.


Assuntos
Artrite Experimental/imunologia , Encefalomielite Autoimune Experimental/imunologia , Fator de Crescimento Placentário/metabolismo , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Animais , Autoimunidade , Diferenciação Celular , Células Cultivadas , Interleucina-17/metabolismo , Interleucina-6/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Knockout , Neovascularização Patológica , Fator de Crescimento Placentário/genética , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
2.
Nano Lett ; 23(11): 5116-5122, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37265068

RESUMO

Significant research has focused on enhancing catalytic performance through solar energy conversion, and the design of photocatalysis incorporating surface plasmons is drawing considerable attention as a highly competitive catalyst system. Although the hot electron process is the primary mechanism in plasmonic photocatalysis, the precise function of hot electron transport in catalytic reactions remains unclear due to the absence of direct measurement. Here, we demonstrate the intrinsic relationship between surface-plasmon-driven hot electrons and catalytic activity during hydrogen oxidation, utilizing catalytic Schottky nanodiodes (Pt/Ag/TiO2) for antenna-reactor plasmonic photocatalysis. The simultaneous and independent measurements of hot electron flow and catalytic turnover rate show that the plasmonic effect amplifies the flow of reaction-induced hot electrons (chemicurrent), leading to enhanced catalytic activity. Plasmonic photocatalytic performance can be controlled with light wavelengths, intensity, surface temperature, and structures. These results elucidate the hot electron flow on photocatalysis and offer improved strategies for efficient catalytic devices.

3.
Int J Mol Sci ; 25(11)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38892219

RESUMO

Anoctamin1 (ANO1), a calcium-activated chloride channel, is overexpressed in a variety of cancer cells, including prostate cancer, and is involved in cancer cell proliferation, migration, and invasion. Inhibition of ANO1 in these cancer cells exhibits anticancer effects. In this study, we conducted a screening to identify novel ANO1 inhibitors with anticancer effects using PC-3 human prostate carcinoma cells. Screening of 2978 approved and investigational drugs revealed that hemin is a novel ANO1 inhibitor with an IC50 value of 0.45 µM. Notably, hemin had no significant effect on intracellular calcium signaling and cystic fibrosis transmembrane conductance regulator (CFTR), a cyclic AMP (cAMP)-regulated chloride channel, and it showed a weak inhibitory effect on ANO2 at 3 µM, a concentration that completely inhibits ANO1. Interestingly, hemin also significantly decreased ANO1 protein levels and strongly inhibited the cell proliferation and migration of PC-3 cells in an ANO1-dependent manner. Furthermore, it strongly induced caspase-3 activation, PARP degradation, and apoptosis in PC-3 cells. These findings suggest that hemin possesses anticancer properties via ANO1 inhibition and could be considered for development as a novel treatment for prostate cancer.


Assuntos
Anoctamina-1 , Antineoplásicos , Hemina , Proteínas de Neoplasias , Neoplasias da Próstata , Humanos , Masculino , Anoctamina-1/metabolismo , Anoctamina-1/antagonistas & inibidores , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Hemina/farmacologia , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/antagonistas & inibidores , Células PC-3 , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia
4.
Mar Drugs ; 21(7)2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37504905

RESUMO

Fucoidans are sulfate-rich polysaccharides with a wide variety of beneficial biological activities. The present study aimed to highlight the anti-inflammatory activity of fucoidan from the brown seaweed Sargassum autumnale (SA) against lipopolysaccharide (LPS)-induced RAW 264.7 macrophage cells. Among the isolated fucoidan fractions, the third fraction (SAF3) showed a superior protective effect on LPS-stimulated RAW 264.7 cells. SAF3 inhibits nitric oxide (NO) production and expression of prostaglandin E-2 (PGE2) via downregulation of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2) expression in LPS-induced RAW 26.7 cells. SAF3 treatment decreased pro-inflammatory cytokines IL-1ß, TNF-α, and IL-6 expression in LPS-induced cells. LPS stimulation activated NF-κB and MAPK signaling cascades in RAW 264.7 cells, while treatment with SAF3 suppressed them in a concentration-dependent manner. Existing outcomes confirm that SAF3 from S. autumnale possesses potent anti-inflammatory activity and exhibits good potential for application as a functional food ingredient or for the treatment of inflammation-related disorders.


Assuntos
NF-kappa B , Sargassum , Animais , Camundongos , NF-kappa B/metabolismo , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Sargassum/metabolismo , Polissacarídeos/farmacologia , Polissacarídeos/metabolismo , Macrófagos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/metabolismo , Células RAW 264.7 , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/metabolismo , Ciclo-Oxigenase 2/metabolismo
5.
Sensors (Basel) ; 23(9)2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37177664

RESUMO

The evolution of mobile communication technology has brought about significant changes in the way people communicate. However, the lack of nonverbal cues in computer-mediated communication can make the accurate interpretation of emotions difficult. This study proposes a novel approach for using emotions as active input in mobile systems. This approach combines psychological and neuroscientific principles to accurately and comprehensively assess an individual's emotions for use as input in mobile systems. The proposed technique combines facial and heart rate information to recognize users' five prime emotions, which can be implemented on mobile devices using a front camera and a heart rate sensor. A user evaluation was conducted to verify the efficacy and feasibility of the proposed technique, and the results showed that users could express emotions faster and more accurately, with average recognition accuracies of 90% and 82% for induced and intended emotional expression, respectively. The proposed technique has the potential to enhance the user experience and provide more personalized and dynamic interaction with mobile systems.


Assuntos
Emoções , Expressão Facial , Humanos , Frequência Cardíaca , Emoções/fisiologia , Comunicação , Sinais (Psicologia)
6.
J Chem Phys ; 157(8): 084701, 2022 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-36050032

RESUMO

Plasmonic photoelectrochemical (PEC) water splitting has excited immense interest, as it can overcome the intrinsic limitations of semiconductors, in terms of light absorption, by the localized-surface plasmon resonances effect. Here, to get insight into the role of plasmonic hot carriers in plasmonic water splitting, a rational design of an antenna-reactor type Pt/Ag/TiO2 metal-semiconductor Schottky nanodiode was fabricated and used as a photoanode. Using the designed PEC cell system combined with the Pt/Ag/TiO2 nanodiode, we show that the plasmonic hot carriers excited from Ag were utilized for the oxygen (O2) evolution reaction and, consequently, had a decisive role in the enhancement of the photocatalytic efficiency. These results were supported by finite-difference time-domain simulations, and the faradaic efficiency was measured by the amount of actual gas produced. Therefore, this study provides a deep understanding of the dynamics and mechanisms of plasmonic hot carriers in plasmonic-assisted PEC water splitting.

7.
Mar Drugs ; 20(8)2022 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-35892939

RESUMO

Ecklonia maxima is a brown seaweed, which is abundantly distributed in South Africa. This study investigated an efficient approach using high-performance centrifugal partition chromatography (HPCPC), which has been successfully developed for the isolation and purification of phlorotannins, eckmaxol, and dieckol from the ethyl acetate fraction of E. maxima (EEM). We evaluated EEM for its inhibitory effect against lipopolysaccharide (LPS)-induced inflammatory responses in zebrafish embryos. The separation of eckmaxol and dieckol from samples of EEM using HPCPC was found to be of high purity and yield under an optimal solvent system composed of n-hexane:ethyl acetate:methanol:water (2:7:3:7, v/v/v/v). To evaluate the anti-inflammatory efficacy of EEM containing active compounds, zebrafish embryos exposed to LPS were compared with and without EEM treatment for nitric oxide (NO) production, reactive oxygen species (ROS) generation, and cell death two days after fertilization. These evaluations indicate that EEM alleviated inflammation by inhibiting cell death, ROS, and NO generation induced by LPS treatment. According to these results, eckmaxol and dieckol isolated from brown seaweed E. maxima could be considered effective anti-inflammatory agents as pharmaceutical and functional food ingredients.


Assuntos
Phaeophyceae , Alga Marinha , Animais , Anti-Inflamatórios/farmacologia , Cromatografia Líquida , Lipopolissacarídeos/farmacologia , Óxido Nítrico/metabolismo , Phaeophyceae/química , Espécies Reativas de Oxigênio/metabolismo , Alga Marinha/metabolismo , África do Sul , Peixe-Zebra/metabolismo
8.
Int J Mol Sci ; 23(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36077221

RESUMO

Poly ADP-ribosylation (PARylation) is a post-translational modification process. Following the discovery of PARP-1, numerous studies have demonstrated the role of PARylation in the DNA damage and repair responses for cellular stress and DNA damage. Originally, studies on PARylation were confined to PARP-1 activation in the DNA repair pathway. However, the interplay between PARylation and DNA repair suggests that PARylation is important for the efficiency and accuracy of DNA repair. PARylation has contradicting roles; however, recent evidence implicates its importance in inflammation, metabolism, and cell death. These differences might be dependent on specific cellular conditions or experimental models used, and suggest that PARylation may play two opposing roles in cellular homeostasis. Understanding the role of PARylation in cellular function is not only important for identifying novel therapeutic approaches; it is also essential for gaining insight into the mechanisms of unexplored diseases. In this review, we discuss recent reports on the role of PARylation in mediating diverse cellular functions and homeostasis, such as DNA repair, inflammation, metabolism, and cell death.


Assuntos
Poli ADP Ribosilação , Poli(ADP-Ribose) Polimerases , Reparo do DNA , Humanos , Inflamação , Poli ADP Ribosilação/genética , Inibidores de Poli(ADP-Ribose) Polimerases , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo
9.
J Neurosci ; 40(44): 8556-8572, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-33020216

RESUMO

Organelle crosstalk is vital for cellular functions. The propinquity of mitochondria, ER, and plasma membrane promote regulation of multiple functions, which include intracellular Ca2+ flux, and cellular biogenesis. Although the purposes of apposing mitochondria and ER have been described, an understanding of altered organelle connectomics related to disease states is emerging. Since inner ear outer hair cell (OHC) degeneration is a common trait of age-related hearing loss, the objective of this study was to investigate whether the structural and functional coupling of mitochondria with subsurface cisternae (SSC) was affected by aging. We applied functional and structural probes to equal numbers of male and female mice with a hearing phenotype akin to human aging. We discovered the polarization of cristae and crista junctions in mitochondria tethered to the SSC in OHCs. Aging was associated with SSC stress and decoupling of mitochondria with the SSC, mitochondrial fission/fusion imbalance, a remarkable reduction in mitochondrial and cytoplasmic Ca2+ levels, reduced K+-induced Ca2+ uptake, and marked plasticity of cristae membranes. A model of structure-based ATP production predicts profound energy stress in older OHCs. This report provides data suggesting that altered membrane organelle connectomics may result in progressive hearing loss.


Assuntos
Células Ciliadas Auditivas Externas/patologia , Perda Auditiva/patologia , Mitocôndrias/patologia , Trifosfato de Adenosina/biossíntese , Envelhecimento/fisiologia , Animais , Cálcio/metabolismo , Conectoma , Citoplasma/metabolismo , Retículo Endoplasmático/patologia , Metabolismo Energético/fisiologia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Feminino , Masculino , Potencial da Membrana Mitocondrial/fisiologia , Camundongos , Plasticidade Neuronal/efeitos dos fármacos , Potássio/farmacologia
10.
Am J Physiol Endocrinol Metab ; 320(2): E379-E389, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33356995

RESUMO

Low-density lipoprotein receptor-related protein 1 (LRP1) is a member of LDL receptor family that plays a key role in systemic glucose and lipid homeostasis. LRP1 also regulates energy balance in the hypothalamus by mediating leptin's anorexigenic action, although the underlying neurocircuitry involved is still unclear. Because GABAergic neurons are a major mediator of hypothalamic leptin action, we studied the role of GABAergic LRP1 in energy balance and leptin action using mice lacking LRP1 in Vgat- or AgRP-expressing neurons (Vgat-Cre; LRP1loxP/loxP or AgRP-Cre; LRP1loxP/loxP). Here, we show that LRP1 deficiency in GABAergic neurons results in severe obesity in male and female mice fed a normal-chow diet. This effect is most likely due to increased food intake and decreased energy expenditure and locomotor activity. Increased adiposity in GABAergic neuron-specific LRP1-deficient mice is accompanied by hyperleptinemia and hyperinsulinemia. Insulin resistance and glucose intolerance in these mice are occurred without change in body weight. Importantly, LRP1 in GABAergic neurons is not required for leptin action, as evidenced by normal leptin's anorexigenic action and leptin-induced hypothalamic Stat3 phosphorylation. In contrast, LRP1 deficiency in AgRP neurons has no effect on adiposity and caloric intake. In conclusion, our data identify GABAergic neurons as a key neurocircuitry that underpins LRP1-dependent regulation of systemic energy balance and body-weight homeostasis. We further find that the GABAergic LRP1 signaling pathway modulates food intake and energy expenditure independently of leptin signaling and AgRP neurons.


Assuntos
Ingestão de Alimentos , Metabolismo Energético , Neurônios GABAérgicos/patologia , Leptina/metabolismo , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/fisiologia , Obesidade/patologia , Receptores para Leptina/metabolismo , Proteína Relacionada com Agouti/genética , Proteína Relacionada com Agouti/metabolismo , Animais , Feminino , Neurônios GABAérgicos/metabolismo , Glucose/metabolismo , Homeostase , Resistência à Insulina , Leptina/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/etiologia , Obesidade/metabolismo , Receptores para Leptina/genética
11.
Nanotechnology ; 32(22)2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33607643

RESUMO

Energy conversion to generate hot electrons through the excitation of localized surface plasmon resonance (LSPR) in metallic nanostructures is an emerging strategy in photovoltaics and photocatalytic devices. Important factors for surface plasmon and hot electron generation are the size, shape, and materials of plasmonic metal nanostructures, which affect LSPR excitation, absorbance, and hot electron collection. Here, we fabricated the ordered structure of metal-semiconductor plasmonic nanodiodes using nanosphere lithography and reactive ion etching. Two types of hole-shaped plasmonic nanostructures with the hole diameter of 280 and 115 nm were fabricated on Au/TiO2Schottky diodes. We show that hot electron flow can be manipulated by changing the size of plasmonic nanostructures on the Schottky diode. We show that the short-circuit photocurrent changes and the incident photon-to-electron conversion efficiency results exhibit the peak shift depending on the structures. These phenomena are explicitly observed with finite difference time domain simulations. The capability of tuning the morphology of plasmonic nanostructure on the Schottky diode can give rise to new possibilities in controlling hot electron generation and developing novel hot-electron-based energy conversion devices.

12.
Mar Drugs ; 19(2)2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33567534

RESUMO

Sargassum horneri (S. horneri) is a well-known brown seaweed widely distributed worldwide. Several biological activities of S. horneri have been reported. However, its effects on lipid metabolism and the underlying mechanisms remain elusive. In the present study, we examined the inhibitory effect of the active compound "(-)-loliolide ((6S,7aR)-6-hydroxy-4,4,7a-trimethyl-5,6,7,7a-tetrahydro-1-benzofuran-2(4H)-one (HTT))" from S. horneri extract on lipid accumulation in differentiated adipocytes. MTT assays demonstrated that (-)-loliolide is not toxic to 3T3-L1 adipocytes in a range of concentrations. (-)-loliolide significantly reduced intracellular lipid accumulation in the differentiated phase of 3T3-L1 adipocytes as shown by Oil Red O staining. Western blot analysis revealed that (-)-loliolide increased the expression of lipolytic protein phospho-hormone-sensitive lipase (p-HSL) and thermogenic protein peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1). Additionally, (-)-loliolide decreased expression of adipogenic and lipogenic proteins, including sterol regulatory element-binding protein-1 (SREBP-1), peroxisome proliferator-activated receptor-γ (PPAR-γ), CCAAT/enhancer-binding protein-α (C/EBP-α), and fatty acid-binding protein 4 (FABP4) in 3T3-L1 adipocytes. These results indicate that (-)-loliolide from S. horneri could suppress lipid accumulation via regulation of antiadipogenic and prolipolytic mechanisms in 3T3-L1 cells. Considering the multifunctional effect of (-)-loliolide, it can be useful as a lipid-lowering agent in the management of patients who suffer from obesity.


Assuntos
Benzofuranos/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Sargassum/química , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Proteína alfa Estimuladora de Ligação a CCAAT/antagonistas & inibidores , Lipólise/efeitos dos fármacos , Camundongos , Obesidade/tratamento farmacológico , PPAR gama/antagonistas & inibidores , Proteína de Ligação a Elemento Regulador de Esterol 1/antagonistas & inibidores , Termogênese/efeitos dos fármacos
13.
Mar Drugs ; 19(2)2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33557339

RESUMO

Grateloupia elliptica (G. elliptica) is a red seaweed with antioxidant, antidiabetic, anticancer, anti-inflammatory, and anticoagulant activities. However, the anti-obesity activity of G. elliptica has not been fully investigated. Therefore, the effect of G. elliptica ethanol extract on the suppression of intracellular lipid accumulation in 3T3-L1 cells by Oil Red O staining (ORO) was evaluated. Among the eight red seaweeds tested, G. elliptica 60% ethanol extract (GEE) exhibited the highest inhibition of lipid accumulation. GEE was the only extract to successfully suppress lipid accumulation among ethanol extracts from eight red seaweeds. In this study, we successfully isolated chlorophyll derivative (CD) from the ethyl acetate fraction (EA) of GEE by high-performance liquid chromatography and evaluated their inhibitory effect on intracellular lipid accumulation in 3T3-L1 adipocytes. CD significantly suppressed intracellular lipid accumulation. In addition, CD suppressed adipogenic protein expression such as sterol regulatory element-binding protein-1 (SREBP-1), peroxisome proliferator-activated receptor-γ (PPAR-γ), CCAAT/enhancer-binding protein-α (C/EBP-α), and fatty acid binding protein 4 (FABP4). Taken together, our results indicate that CD from GEE inhibits lipid accumulation by suppressing adipogenesis via the downregulation of adipogenic protein expressions in the differentiated adipocytes. Therefore, chlorophyll from G. elliptica has a beneficial effect on lipid metabolism and it could be utilized as a potential therapeutic agent for preventing obesity.


Assuntos
Adipogenia/efeitos dos fármacos , Clorofila/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Alga Marinha , Células 3T3-L1 , Animais , Proteínas Estimuladoras de Ligação a CCAAT/genética , Clorofila/análogos & derivados , Clorofila/uso terapêutico , Cromatografia Líquida de Alta Pressão , Regulação para Baixo , Proteínas de Ligação a Ácido Graxo/genética , Camundongos , Obesidade/tratamento farmacológico , PPAR gama/genética , Alga Marinha/química , Proteína de Ligação a Elemento Regulador de Esterol 1/genética
14.
J Immunol ; 200(2): 749-757, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29246953

RESUMO

In inflammatory arthritis, the dysregulation of osteoclast activity by proinflammatory cytokines, including TNF, interferes with bone remodeling during inflammation through Ca2+-dependent mechanisms causing pathological bone loss. Ca2+-dependent CREB/c-fos activation via Ca2+-calmodulin kinase IV (CaMKIV) induces transcriptional regulation of osteoclast-specific genes via NFATc1, which facilitate bone resorption. In leukocytes, Ca2+ regulation of NFAT-dependent gene expression oftentimes involves the activity of the Ca2+-activated K+ channel KCa3.1. In this study, we evaluate KCa3.1 as a modulator of Ca2+-induced NFAT-dependent osteoclast differentiation in inflammatory bone loss. Microarray analysis of receptor activator of NF-κB ligand (RANKL)-activated murine bone marrow macrophage (BMM) cultures revealed unique upregulation of KCa3.1 during osteoclastogenesis. The expression of KCa3.1 in vivo was confirmed by immunofluorescence staining on multinucleated cells at the bone surface of inflamed mouse joints. Experiments on in vitro BMM cultures revealed that KCa3.1-/- and TRAM-34 treatment significantly reduced the expression of osteoclast-specific genes (p < 0.05) alongside decreased osteoclast formation (p < 0.0001) in inflammatory (RANKL+TNF) and noninflammatory (RANKL) conditions. In particular, live cell Ca2+ imaging and Western blot analysis showed that TRAM-34 pretreatment decreased transient RANKL-induced Ca2+ amplitudes in BMMs by ∼50% (p < 0.0001) and prevented phosphorylation of CaMKIV. KCa3.1-/- reduced RANKL+/-TNF-stimulated phosphorylation of CREB and expression of c-fos in BMMs (p < 0.01), culminating in decreased NFATc1 protein expression and transcriptional activity (p < 0.01). These data indicate that KCa3.1 regulates Ca2+-dependent NFATc1 expression via CaMKIV/CREB during inflammatory osteoclastogenesis in the presence of TNF, corroborating its role as a target candidate for the treatment of bone erosion in inflammatory arthritis.


Assuntos
Reabsorção Óssea/genética , Reabsorção Óssea/metabolismo , Cálcio/metabolismo , Regulação da Expressão Gênica , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/metabolismo , Fatores de Transcrição NFATC/genética , Osteoclastos/metabolismo , Animais , Proteína de Ligação a CREB/metabolismo , Diferenciação Celular , Células Cultivadas , Camundongos , Camundongos Knockout , Fatores de Transcrição NFATC/metabolismo , Osteoclastos/citologia , Ligação Proteica , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ligante RANK/metabolismo
15.
Mar Drugs ; 18(12)2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33317054

RESUMO

Fucosterol is a phytosterol that is abundant in marine brown algae and is a renowned secondary metabolite. However, its ability to protect macrophages against particulate matter (PM) has not been clarified with regard to inflammation; thus, this study aimed to illustrate the above. Padina boryana, a brown algae that is widespread in Indo-Pacific waters, was applied in the isolation of fucosterol. Isolation was conducted using silica open columns, while identification was assisted with gas chromatography-mass spectroscopy (GC-MS) and NMR. Elevated levels of PM led the research objectives toward the implementation of it as a stimulant. Both inflammation and oxidative stress were caused due the fact of its effect. RAW 264.7 macrophages were used as a model system to evaluate the process. It was apparent that the increased NO production levels, due to the PM, were mediated through the inflammatory mediators, such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and pro-inflammatory cytokines (i.e., interleukin-6 (IL-6), interleukin-1 (IL-1ß) and tumor necrosis factor-α (TNF-α), including prostaglandin E2 (PGE2)). Further, investigations provided solid evidence regarding the involvement of NF-κB and mitogen-activated protein kinases (MAPKs) in the process. Oxidative stress/inflammation which are inseparable components of the cellular homeostasis were intersected through the Nrf2/HO-1 pathway. Conclusively, fucosterol is a potent protector against PM-induced inflammation in macrophages and hence be utilized as natural product secondary metabolite in a sustainable manner.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Heme Oxigenase-1/metabolismo , Macrófagos/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Phaeophyceae , Estigmasterol/análogos & derivados , Animais , Anti-Inflamatórios/isolamento & purificação , Antioxidantes/isolamento & purificação , Citocinas/genética , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Macrófagos/enzimologia , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Material Particulado/toxicidade , Phaeophyceae/química , Fosforilação , Células RAW 264.7 , Transdução de Sinais , Estigmasterol/isolamento & purificação , Estigmasterol/farmacologia
16.
J Immunol ; 198(1): 452-460, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27895169

RESUMO

IL-23 activates the synthesis and production of leukotriene B4 (LTB4) in myeloid cells, which modulate inflammatory arthritis. In this study we investigated the role of LTB4 and its receptor LTB4R1 (BLT1) in synovial inflammation and osteoclast differentiation. Specifically, we used IL-23 in vivo gene transfer to induce arthritis in mice and showed that elevated serum LTB4 and synovial expression of 5-lipoxygenase correlated with increased disease severity by histological evaluation and paw swelling compared with GFP gene transfer controls. To further investigate the effect of the LTB4 pathway in bone loss, we performed osteoclast differentiation assays by stimulating with M-CSF and receptor activator of NF-κB ligand bone marrow cells derived from BLT1+/+ and/or BLT1-/- mice and used quantitative PCR for gene expression analysis in terminally differentiated osteoclasts. Deficiency in BLT1 resulted in the upregulation of osteoclast-related genes and an increase in the formation of giant, multinucleated TRAP+ cells capable of F-actin ring formation. Additionally, BLT1 deficiency showed an increase of phosphorylated NF-κB and phosphorylated IκB levels in osteoclasts. We also performed real-time calcium imaging to study the effect of BLT1 deficiency in receptor activator of NF-κ-B ligand-induced activation of intracellular calcium flux in vitro. Our data show that LTB4 and its receptor BLT1 exacerbate synovial inflammation in vivo and bone resorption in vitro, suggesting that LTB4 and BLT1 could be effectively targeted for the treatment of musculoskeletal diseases.


Assuntos
Artrite Experimental/metabolismo , Artrite Reumatoide/metabolismo , Leucotrieno B4/metabolismo , Osteogênese/fisiologia , Receptores do Leucotrieno B4/metabolismo , Animais , Artrite Experimental/patologia , Artrite Reumatoide/patologia , Western Blotting , Citometria de Fluxo , Imuno-Histoquímica , Inflamação/metabolismo , Inflamação/patologia , Interleucina-23/imunologia , Masculino , Camundongos , Camundongos Knockout , NF-kappa B/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Osteoclastos/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Membrana Sinovial/metabolismo , Membrana Sinovial/patologia , Transcriptoma
17.
Mar Drugs ; 17(1)2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30634617

RESUMO

The purpose of this study was to investigate the antiobesity effect and the mechanism of action of diphlorethohydroxycarmalol (DPHC) isolated from Ishige okamurae in 3T3-L1 cells. The antiobesity effects were examined by evaluating intracellular fat accumulation in Oil Red O-stained adipocytes. Based on the results, DPHC dose-dependently inhibited the lipid accumulation in 3T3-L1 adipocytes. DPHC significantly inhibited adipocyte-specific proteins such as SREBP-1c, PPARγ, C/EBP α, and adiponectin, as well as adipogenic enzymes, including perilipin, FAS, FABP4, and leptin in adipocytes. These results indicated that DPHC primarily acts by regulating adipogenic-specific proteins through inhibiting fat accumulation and fatty acid synthesis in adipocytes. DPHC treatment significantly increased both AMPK and ACC phosphorylation in adipocytes. These results indicate that DPHC inhibits the fat accumulation by activating AMPK and ACC in 3T3-L1 cells. Taken together, these results suggest that DPHC can be used as a potential therapeutic agent against obesity.


Assuntos
Adenilato Quinase/metabolismo , Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Células 3T3-L1 , Adenilato Quinase/genética , Animais , Sobrevivência Celular , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/química , Camundongos , Estrutura Molecular , Alga Marinha/química
18.
Mar Drugs ; 17(11)2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31717668

RESUMO

Diphlorethohydroxycarmalol (DPHC) is one of the most abundant bioactive compounds in Ishige okamurae. The previous study suggested that DPHC possesses strong in vitro anti-obesity activity in 3T3-L1 cells. However, the in vivo anti-obesity effect of DPHC has not been determined. The current study explored the effect of DPHC on high-fat diet (HFD)-induced obesity in C57BL/6J mice. The results indicated that oral administration of DPHC (25 and 50 mg/kg/day for six weeks) significantly and dose-dependently reduced HFD-induced adiposity and body weight gain. DPHC not only decreased the levels of triglyceride, low-density lipoprotein cholesterol, leptin, and aspartate transaminase but also increased the level of high-density lipoprotein cholesterol in the serum of HFD mice. In addition, DPHC significantly reduced hepatic lipid accumulation by reduction of expression levels of the critical enzymes for lipogenesis including SREBP-1c, FABP4, and FAS. Furthermore, DPHC remarkably reduced the adipocyte size, as well as decreased the expression levels of key adipogenic-specific proteins and lipogenic enzymes including PPARγ, C/EBPα, SREBP-1c, FABP4, and FAS, which regulate the lipid metabolism in the epididymal adipose tissue (EAT). Further studies demonstrated that DPHC significantly stimulated the phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) in both liver and EAT. These results demonstrated that DPHC effectively prevented HFD-induced obesity and suggested that DPHC could be used as a potential therapeutic agent for attenuating obesity and obesity-related diseases.


Assuntos
Fármacos Antiobesidade/farmacologia , Compostos Heterocíclicos com 3 Anéis/farmacologia , Obesidade/tratamento farmacológico , Phaeophyceae/metabolismo , Tecido Adiposo/efeitos dos fármacos , Administração Oral , Animais , Fármacos Antiobesidade/administração & dosagem , Fármacos Antiobesidade/isolamento & purificação , Dieta Hiperlipídica , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Compostos Heterocíclicos com 3 Anéis/administração & dosagem , Compostos Heterocíclicos com 3 Anéis/isolamento & purificação , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipogênese/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/fisiopatologia , Aumento de Peso/efeitos dos fármacos
19.
Endocr J ; 65(4): 437-447, 2018 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-29434073

RESUMO

Placental growth factor (PlGF), a member of the vascular endothelial growth factor (VEGF) sub-family, plays a major role in angiogenesis and vasculogenesis. Previous study demonstrated that PlGF-overexpressing transgenic (Tg) mice had gestational loss. In addition, PlGF secretion was up-regulated in isolated T lymphocytes (T-cell) upon CD3/CD28 stimulation, suggesting that PlGF could be a regulator of T-cell differentiation and development. T-cells are well known to play a critical role in obesity-induced inflammation. Therefore, to verify the possible link of diet-induced obesity (DIO) with inflammation and related metabolic disorders, such as insulin resistance, we fed high-fat diet (HFD) to Tg mice for 16 weeks. Adiposity and glucose intolerance significantly increase in Tg mice fed a HFD (Tg HFD) compared to wild-type (WT) mice fed HFD (WT HFD). In addition, macrophage infiltrations were significantly higher in the epididymal white adipose tissue (EWAT), liver, and pancreatic islets of Tg HFD mice compared to WT HFD mice. In the in vitro study, we showed that isolated CD4+ T-cells from Tg mice further differentiate into type 1 (Th1) and type 17 (Th17) helper T-cells via CD3/CD28 stimulation. Furthermore, we observed that the pro-inflammatory cytokines IL-6, IL-17, and TNFα, are remarkably increased in Tg mice compared to WT mice. These findings demonstrate that PlGF overexpression in T-cells might lead to inflammatory T-cell differentiation and accumulation in adipose tissue (AT) or metabolism-related tissues, contributing to the development of systemic metabolic disorders. Thus, PlGF may provide an effective therapeutic target in the management of obesity-induced inflammation and related metabolic disorders.


Assuntos
Citocinas/biossíntese , Dieta Hiperlipídica/efeitos adversos , Inflamação/metabolismo , Obesidade/metabolismo , Fator de Crescimento Placentário/metabolismo , Adiposidade/fisiologia , Animais , Inflamação/genética , Resistência à Insulina/fisiologia , Camundongos , Camundongos Transgênicos , Obesidade/etiologia , Fator de Crescimento Placentário/genética
20.
Mar Drugs ; 16(4)2018 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-29561805

RESUMO

Soft corals are known to be prolific producers of a wide spectrum of biologically active cembranoids. One new cembranoid, sinularolide F (2), along with three known compounds, cembranolide (1), (E,E,E)-6,10,14-trimethyl-3-methylene-cis-3α,4,5,8,9,12,13,15α-octahydrocyclo tetradeca[ß]furan-2(3H)-one (3), and denticulatolide (4), were isolated from the Bornean soft coral Sinularia sp. Compounds 2 and 4 showed potential anti-inflammatory activities against lipopolysaccharide-stimulated RAW 264.7 with IC50 values less than 6.25 µg/mL and anticancer activity against HL60 cell lines. The compounds' mechanisms of action were investigated via the Western blot evaluation of their protein markers. These activities could be attributed to the presence of tertiary methyl at C-8 and the compounds' 3D configurations.


Assuntos
Antozoários/química , Anti-Inflamatórios/farmacologia , Animais , Antozoários/metabolismo , Anti-Inflamatórios/química , Anti-Inflamatórios/metabolismo , Diterpenos/química , Diterpenos/farmacologia , Camundongos , Estrutura Molecular , Células RAW 264.7
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