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A mild and efficient method for photoredox-catalyzed bromonitroalkylation of alkenes is described herein. In this reaction, bromonitromethane serves as a source of both nitroalkyl and bromine for direct and regioselective formation of C-Br and C-C bonds from alkenes, and additional cyclization provides C-C bonds to the cyclopropylamine core as an LSD1 inhibitor.
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In our search for bioactive components, various chromatographic separations of the organic fractions from Filipendula glaberrima leaves led to the isolation of a new ellagitannin and a triterpenoid, along with 26 known compounds. The structures of the isolates were determined based on their spectroscopic properties and chemical evidence, which were then evaluated for their antioxidant activities, inhibitory activities on 3-hydroxy-3-methylglutaryl-coenzyme A reductase, and foam cell formation in THP-1 cells to prevent atherosclerosis. Rugosin B methyl ester (1) showed the best HMG-CoA reductase inhibition and significantly reduced ox-low-density lipoprotein-induced THP-1 macrophage-derived foam cell formation at 25 µM. In addition, no cytotoxicity was observed in THP-1 cells at 50 µg/mL of all extracts in the macrophage foam cell formation assay. Therefore, F. glaberrima extract containing 1 is promising in the development of dietary supplements due to its potential behavior as a novel source of nutrients for preventing and treating atherosclerosis.
Assuntos
Acil Coenzima A , Aterosclerose , Filipendula , Células Espumosas , Antioxidantes/farmacologia , Hidroximetilglutaril-CoA-Redutases NADP-Dependentes , Macrófagos , Aterosclerose/tratamento farmacológico , Folhas de PlantaRESUMO
Fluorescent dyes have garnered significant attention as theranostic platforms owing to their inherent characteristics. In this study, we present the discovery of Medical Fluorophore 33 (MF33), a novel and potent theranostic agent with a phenaleno-isoquinolinium salt structure that can serve as a cancer therapeutic strategy. The synthesis of MF33 is readily achievable through a simple Rh(III)-catalyzed reaction. Moreover, MF33 displayed strong fluorescence signals, excellent microsomal stability, and high biocompatibility in vivo. It induces significant apoptosis in cancer cells via the p53/p21/caspase-3 signaling pathway, leading to selective cytotoxicity in various cancer cells. In vivo fluorescence imaging with MF33 enabled the visualization of sentinel lymph nodes in living mice. Notably, repeated intraperitoneal administration of MF33 resulted in antitumor activity in mice with colorectal cancer. Collectively, our findings suggest that phenaleno-isoquinolinium salt-based MF33 is a viable theranostic agent for biomedical imaging and cancer treatment.
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Corantes Fluorescentes , Neoplasias , Animais , Camundongos , Corantes Fluorescentes/química , Medicina de Precisão , Estudos de Viabilidade , Neoplasias/terapia , Nanomedicina Teranóstica/métodosRESUMO
BACKGROUND: N-methyl-D-aspartate receptors (NMDARs) are considered to be involved in several physiological and pathophysiological processes in addition to the progression of neurological disorders. However, how NMDARs are involved in the glycolytic phenotype of M1 macrophage polarization and the possibility of using them as a bio-imaging probe for macrophage-mediated inflammation remain unclear. METHODS: We analyzed cellular responses to NMDAR antagonism and small interfering RNAs using mouse bone marrow-derived macrophages (BMDMs) treated with lipopolysaccharide (LPS). An NMDAR targeting imaging probe, N-TIP, was produced via the introduction of NMDAR antibody and the infrared fluorescent dye FSD Fluor™ 647. N-TIP binding efficiency was tested in intact and LPS-stimulated BMDMs. N-TIP was intravenously administered to mice with carrageenan (CG)- and LPS-induced paw edema, and in vivo fluorescence imaging was conducted. The anti-inflammatory effects of dexamethasone were evaluated using the N-TIP-mediated macrophage imaging technique. RESULTS: NMDARs were overexpressed in LPS-treated macrophages, subsequently inducing M1 macrophage polarization. Mechanistically, NMDAR-mediated Ca2+ accumulation resulted in LPS-stimulated glycolysis via upregulation of PI3K/AKT/mTORC1 signaling. In vivo fluorescence imaging with N-TIP showed LPS- and CG-induced inflamed lesions at 5 h post-inflammation, and the inflamed lesions could be detected until 24 h. Furthermore, our N-TIP-mediated macrophage imaging technique helped successfully visualize the anti-inflammatory effects of dexamethasone in mice with inflammation. CONCLUSION: This study demonstrates that NMDAR-mediated glycolysis plays a critical role in M1 macrophage-related inflammation. Moreover, our results suggest that NMDAR targeting imaging probe may be useful in research on inflammatory response in vivo.
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Fluorescence imaging agents have recently received huge attention due to their important role in disease diagnostics. However, the intrinsic problems of these probes, such as complex synthetic routes and high molecular weight, remain challenging. Here, we developed novel phenaleno isoquinolinium-based fluorescent agents, Medical Fluorophores 37-41 (MF37-41), applicable to the quantitative and sensitive detection of sentinel lymph nodes (SLNs). These imaging agents showed no adverse effects on the proliferation of immune and normal cells and did not induce in vivo toxicity. In vivo fluorescence lifetime imaging demonstrated the accumulation of phenaleno isoquinolinium salts in the SLNs of nude mice within 15 min postinjection, consistent with our biodistribution findings. These results suggest that phenaleno isoquinolinium salts are feasible fluorescence imaging agents that can be used as potential lymphatic tracers.
Assuntos
Materiais Biocompatíveis/química , Descoberta de Drogas , Corantes Fluorescentes/química , Isoquinolinas/química , Imagem Óptica , Fenalenos/química , Linfonodo Sentinela/diagnóstico por imagem , Animais , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/síntese química , Linhagem Celular , Cricetulus , Corantes Fluorescentes/administração & dosagem , Corantes Fluorescentes/síntese química , Injeções Intravenosas , Isoquinolinas/administração & dosagem , Teste de Materiais , Camundongos , Estrutura Molecular , Fenalenos/administração & dosagemRESUMO
Fluorescent imaging agents with biocompatibility and high sensitivity are urgently required for the accurate detection of sentinel lymph nodes (SLNs). Herein, we report the design of a novel quinoline-based fluorescent probe, designated KSNP117, which can be applied as a biomedical imaging agent in the sensitive and quantitative detection of SLNs. KSNP117 exerted no adverse effects on the proliferation of ovary and immune cells and also showed excellent serum stability with photo-brightening effects. In vivo fluorescent imaging revealed the accumulation of KSNP117 in the SLNs of nude mice within 10 min post injection, without in vivo toxicity, which was consistent with the findings of ex vivo imaging. These results support the potential of KSNP117 as a promising lymphatic tracer for biomedical imaging applications.
Assuntos
Corantes Fluorescentes/química , Imagem Óptica/métodos , Quinolinas/química , Linfonodo Sentinela/diagnóstico por imagem , Animais , Feminino , Masculino , CamundongosRESUMO
The presence of brown adipocytes within white adipose tissue is associated with phenotypes that exhibit improved metabolism and proper body weight maintenance. Therefore, a variety of dietary agents that facilitate the browning of white adipocytes have been investigated. In this study, we screened a natural product library comprising 133 compounds with the potential to promote the browning of white adipocytes, and found that D-mannitol induces the browning of 3T3-L1 adipocytes by enhancing the expression of brown fat-specific genes and proteins, and upregulating lipid metabolism markers. D-mannitol also increased the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase 1 (ACC), suggesting a possible role in lipolysis and fat oxidation. Moreover, an increase in the expression of genes associated with D-mannitol-induced browning was strongly correlated with the activation of the ß3-adrenergic receptor as well as AMPK, protein kinase A (PKA), and PPARγ coactivator 1α (PGC1α). D-mannitol effectively reduced the body weight of mice fed a high-fat diet, and increased the expression of ß1-oxidation and energy expenditure markers, such as Cidea, carnitine palmityl transferase 1 (CPT1), uncoupling protein 1 (UCP1), PGC1α, and acyl-coenzyme A oxidase (ACOX1) in the inguinal white adipose tissue. Our findings suggest that D-mannitol plays a dual regulatory role by inducing the generation of a brown fat-like phenotype and enhancing lipid metabolism. These results indicate that D-mannitol can function as an anti-obesity supplement.
Assuntos
Tecido Adiposo Marrom/metabolismo , Manitol/farmacologia , Receptores Adrenérgicos beta 3/metabolismo , Células 3T3-L1 , Proteínas Quinases Ativadas por AMP/metabolismo , Adipócitos Marrons/efeitos dos fármacos , Adipócitos Marrons/metabolismo , Animais , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Manitol/química , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Modelos Animais , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Fenótipo , Transdução de Sinais/efeitos dos fármacos , Proteína Desacopladora 1/metabolismoRESUMO
Despite its outstanding clinical success, immune checkpoint blockade remains ineffective in many patients. Accordingly, combination therapy capable of achieving greater antitumor immunity is urgently required. Here, we report that limiting glutamine metabolism in cancer cells bolsters the effectiveness of anti-programmed death ligand-1 (PD-L1) antibody. Inhibition of glutamine utilization increased PD-L1 levels in cancer cells, thereby inactivating co-cultured T cells. Under glutamine-limited conditions, reduced cellular GSH levels caused an upregulation of PD-L1 expression by impairing SERCA activity, which activates the calcium/NF-κB signaling cascade. Consequently, in tumors grown in immunocompetent mice, inhibition of glutamine metabolism decreased the antitumor activity of T cells. In combination with anti-PD-L1, however, glutamine depletion strongly promoted the antitumor efficacy of T cells in vitro and in vivo due to simultaneous increases in Fas/CD95 levels. Our results demonstrate the relevance of cancer glutamine metabolism to antitumor immunity and suggest that co-targeting of glutamine metabolism and PD-L1 represents a promising therapeutic approach.
Assuntos
Anticorpos Monoclonais/farmacologia , Antígeno B7-H1/metabolismo , Glutamina/metabolismo , Glutationa/metabolismo , Neoplasias/imunologia , Neoplasias/prevenção & controle , Linfócitos T/imunologia , Idoso , Animais , Apoptose , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Proliferação de Células , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Neoplasias/metabolismo , Neoplasias/patologia , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/antagonistas & inibidores , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Bruton's tyrosine kinase (BTK) is an attractive target for treating patients with B cell malignancies and autoimmune diseases. Many BTK inhibitors have been identified; however, like other kinase inhibitors, they lack diversity in their core structures. Therefore, it is important to secure a novel scaffold that occupies the adenine-binding site of BTK. We screened an in-house library of natural products and their analogs via a biochemical assay to identify a novel scaffold for targeting BTK. A pyranochromenone scaffold, derived from a natural active component decursin, was found to be effective at targeting BTK and was selected for further optimization. A series of pyranochromenone analogs was synthesized through the modification of pyranochromenone at the C7 position. Pyranochromenone compounds with an electrophilic warhead exhibited promising BTK inhibitory activity, with IC50 values in the range of 0.5-0.9 µM. A docking study of the representative compound 8 provided a reasonable explanation for compound activity. Compound 8 demonstrated good selectivity over other associated kinases and decreased the production of proinflammatory cytokines in THP cells. Moreover, compound 8 presented significant in vivo efficacy in a murine model of collagen-induced arthritis.
Assuntos
Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Antirreumáticos/farmacologia , Benzopiranos/farmacologia , Produtos Biológicos/farmacologia , Butiratos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Tirosina Quinase da Agamaglobulinemia/química , Tirosina Quinase da Agamaglobulinemia/metabolismo , Animais , Antirreumáticos/química , Artrite Experimental/prevenção & controle , Benzopiranos/química , Produtos Biológicos/química , Butiratos/química , Humanos , Masculino , Camundongos Endogâmicos DBA , Simulação de Acoplamento Molecular , Estrutura Molecular , Domínios Proteicos , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade , Células THP-1RESUMO
Structure-based targeting of fluorescent dyes is essential for their use as imaging agents for disease diagnosis. Here, we describe the development of the benzoquinolizinium compound Medical fluorophore 1 (MF1) as a novel biomedical imaging agent that allows the visualization of inflammation by virtue of its unique chemical structure. Lipopolysaccharide treatment stimulated the uptake of MF1 by bone marrow-derived macrophages, with no adverse effects on cell proliferation. In vivo fluorescence lifetime imaging revealed the accumulation of MF1 in carrageenan-induced acute inflammatory lesions in mice, which peaked at 6 h. MF1-based imaging also allowed monitoring of the response to the anti-inflammatory drugs dexamethasone and sulfasalazine. Thus, MF1 can be used to diagnose diseases characterized by inflammation as well as treatment efficacy.
Assuntos
Corantes Fluorescentes/química , Compostos de Amônio Quaternário/química , Animais , Anti-Inflamatórios/farmacologia , Proliferação de Células , Citocinas/metabolismo , Dexametasona/farmacologia , Fibroblastos/efeitos dos fármacos , Humanos , Inflamação , Lipopolissacarídeos/química , Macrófagos/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Camundongos , Microscopia Confocal , Sulfassalazina/farmacologiaRESUMO
Proper regulation of mTORC1 and mTORC2 upon nutrient starvation is critical for cancer cell survival. Upregulation of Sestrin2 in response to glutamine deprivation rescues cell death by suppressing mTORC1. However, the contribution of mTORC2 to Sestrin2-mediated mTORC1 suppression remains unclear. Here, we report that both Sestrin2 and mTORC2 are upregulated in glutamine-depleted lung cancer cells. Moreover, glutamine depletion caused Sestrin2 to associate with mTORC2, which was required for the increase in Sestrin2 protein stability and the reduction in mTORC1 activity. Ultimately, differential regulation of mTORC1 and 2 by Sestrin2 reprogramed lipid metabolism and enabled glutamine-depleted lung cancer cells to survive by maintaining energy and redox balance. Importantly, combined inhibition of glutamine utilization and Sestrin2 induced lung cancer cell death both in vitro and in vivo. This study shows that differential Sestrin2-mediated regulation of mTORC1 and mTORC2 is necessary for the survival of glutamine-depleted lung cancer cells.
Assuntos
Glutamina , Neoplasias Pulmonares/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Sobrevivência Celular , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Células Tumorais CultivadasRESUMO
The tyrosine kinase inhibitor sorafenib is the only therapeutic agent approved for the treatment of advanced hepatocellular carcinoma (HCC), but acquired resistance to sorafenib is high. Here, we report metabolic reprogramming in sorafenib-resistant HCC and identify a regulatory molecule, peroxisome proliferator-activated receptor-δ (PPARδ), as a potential therapeutic target. Sorafenib-resistant HCC cells showed markedly higher glutamine metabolism and reductive glutamine carboxylation, which was accompanied by increased glucose-derived pentose phosphate pathway and glutamine-derived lipid biosynthetic pathways and resistance to oxidative stress. These glutamine-dependent metabolic alterations were attributed to PPARδ, which was upregulated in sorafenib-resistant HCC cells and human HCC tissues. Furthermore, PPARδ contributed to increased proliferative capacity and redox homeostasis in sorafenib-resistant HCC cells. Accordingly, inhibiting PPARδ activity reversed compensatory metabolic reprogramming in sorafenib-resistant HCC cells and sensitized them to sorafenib. Therefore, targeting compensatory metabolic reprogramming of glutamine metabolism in sorafenib-resistant HCC by inhibiting PPARδ constitutes a potential therapeutic strategy for overcoming sorafenib-resistance in HCC.Implications: This study provides novel insight into the mechanism underlying sorafenib resistance and a potential therapeutic strategy targeting PPARδ in advanced hepatocellular carcinoma. Mol Cancer Res; 15(9); 1230-42. ©2017 AACR.
Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Glutamina/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Niacinamida/análogos & derivados , PPAR delta/metabolismo , Compostos de Fenilureia/farmacologia , Animais , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Niacinamida/farmacologia , PPAR delta/genética , Distribuição Aleatória , Sorafenibe , Transfecção , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Renal tubulointerstitial fibrosis is a common feature of the final stage of nearly all cause types of chronic kidney disease. Although classic peroxisome proliferator-activated receptor γ (PPARγ) agonists have a protective effect on diabetic nephropathy, much less is known about their direct effects in renal fibrosis. This study aimed to investigate possible beneficial effects of lobeglitazone, a novel PPARγ agonist, on renal fibrosis in mice. METHODS: We examined the effects of lobeglitazone on renal tubulointerstitial fibrosis in unilateral ureteral obstruction (UUO) induced renal fibrosis mice. We further defined the role of lobeglitazone on transforming growth factor (TGF)-signaling pathways in renal tubulointerstitial fibrosis through in vivo and in vitro study. RESULTS: Through hematoxylin/eosin and sirius red staining, we observed that lobeglitazone effectively attenuates UUO-induced renal atrophy and fibrosis. Immunohistochemical analysis in conjunction with quantitative reverse transcription polymerase chain reaction and Western blot analysis revealed that lobeglitazone treatment inhibited UUO-induced upregulation of renal Smad-3 phosphorylation, α-smooth muscle actin, plasminogen activator inhibitor 1, and type 1 collagen. In vitro experiments with rat mesangial cells and NRK-49F renal fibroblast cells suggested that the effects of lobeglitazone on UUO-induced renal fibrosis are mediated by inhibition of the TGF-ß/Smad signaling pathway. CONCLUSION: The present study demonstrates that lobeglitazone has a protective effect on UUO-induced renal fibrosis, suggesting that its clinical applications could extend to the treatment of non-diabetic origin renal disease.
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BACKGROUND: Ginsenoside Rg1 is a class of steroid glycoside and triterpene saponin in Panax ginseng. Many studies suggest that Rg1 suppresses adipocyte differentiation in 3T3-L1. However, the detail molecular mechanism of Rg1 on adipogenesis in 3T3-L1 is still not fully understood. METHODS: 3T3-L1 preadipocyte was used to evaluate the effect of Rg1 on adipocyte development in the differentiation in a stage-dependent manner in vitro. Oil Red O staining and Nile red staining were conducted to measure intracellular lipid accumulation and superoxide production, respectively. We analyzed the protein expression using Western blot in vitro. The zebrafish model was used to investigate whether Rg1 suppresses the early stage of fat accumulation in vivo. RESULTS: Rg1 decreased lipid accumulation in early-stage differentiation of 3T3-L1 compared with intermediate and later stages of adipocyte differentiation. Rg1 dramatically increased CAAT/enhancer binding protein (C/EBP) homologous protein-10 (CHOP10) and subsequently reduced the C/EBPß transcriptional activity that prohibited the initiation of adipogenic marker expression as well as triglyceride synthase. Rg1 decreased the expression of extracellular signal-regulated kinase 1/2 and glycogen synthase kinase 3ß, which are also essential for stimulating the expression of CEBPß. Rg1 also reduced reactive oxygen species production because of the downregulated protein level of nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) oxidase 4 (NOX4). While Rg1 increased the endogenous antioxidant enzymes, it also dramatically decreased the accumulation of lipid and triglyceride in high fat diet-induced obese zebrafish. CONCLUSION: We demonstrated that Rg1 suppresses early-stage differentiation via the activation of CHOP10 and attenuates fat accumulation in vivo. These results indicate that Rg1 might have the potential to reduce body fat accumulation in the early stage of obesity.
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Seapolynol (SN) is a polyphenol mixture derived from Ecklonia cava. We evaluated the effects of SN on lipid accumulation in adipocytes, zebrafish, and mice. SN effectively inhibited lipid accumulation in three experimental models by suppressing adipogenic factors. Triglyceride synthetic enzymes such as diacylglycerol acyltransferase 1 (DGAT1) and GPAT3 were also downregulated by SN. This SN-induced inhibition of adipogenic factors was shown to be due to the regulatory effect of SN on early adipogenic factors; SN downregulated the expression of Krueppel-like factor 4 (KLF4), KLF5, CCAAT-enhancer-binding protein ß (C/EBPß), C/EBPδ, and Protein C-ets-2 (ETS2), while KLF2, an anti-early adipogenic factor, was upregulated by SN. SN-mediated inhibition in early adipogenesis was closely correlated with the inhibition of mitotic clonal expansion via cell cycle arrest. SN inhibited cell cycle progression by suppressing cell cycle regulators, such as cyclin A, cyclinD, and pRb but increased p27, a cell cycle inhibitor. In a mouse study, SN effectively reduced body weight and plasma lipid increases induced by a high-fat diet; triglycerides, total cholesterol, and low-density lipoprotein (LDL) levels were markedly reduced by SN. Moreover, SN remarkably improved high-fat-diet-induced hepatic lipid accumulation. Furthermore, SN activated AMP-activated protein kinase-α (AMPKα), an energy sensor, to suppress acetyl-coA carboxylase (ACC), inhibiting lipid synthesis. Our study suggests that SN may be an edible agent that can play a positive role in prevention of metabolic disorders.
Assuntos
Adipócitos/fisiologia , Fármacos Antiobesidade/farmacologia , Diferenciação Celular/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Polifenóis/farmacologia , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Adiposidade , Animais , Fármacos Antiobesidade/isolamento & purificação , Fármacos Antiobesidade/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Fator 4 Semelhante a Kruppel , Masculino , Camundongos , Camundongos Endogâmicos ICR , Mitose/efeitos dos fármacos , Obesidade/tratamento farmacológico , Phaeophyceae/química , Polifenóis/isolamento & purificação , Polifenóis/uso terapêutico , Transdução de Sinais , Peixe-ZebraRESUMO
Kaempferol is a flavonoid present in Kaempferia galanga and Opuntia ficus indica var. saboten. Recent studies have suggested that it has anti-oxidant, anti-inflammatory, anti-cancer, and anti-obesity effects. In this study, we focused on the anti-adipogenic effects of kaempferol during adipocyte differentiation. The results showed that kaempferol inhibits lipid accumulation in adipocytes and zebrafish. Oil Red O and Nile Red staining showed that the number of intracellular lipid droplets decreased in adipocytes and zebrafish treated with kaempferol. LPAATθ (lysophosphatidic acid acyltransferase), lipin1, and DGAT1 (triglyceride synthetic enzymes) and FASN and SREBP-1C (fatty acid synthetic proteins) showed decreased expression levels in the presence of kaempferol. In addition, treatment of kaempferol showed an inhibitory activity on cell cycle progression. Kaempferol delayed cell cycle progression from the S to G2/M phase through the regulation of cyclins in a dose-dependent manner. Kaempferol blocked the phosphorylation of AKT (protein kinase B) and mammalian target of rapamycin (mTOR) signaling pathway during the early stages of adipogenesis. In addition, kaempferol down-regulated pro-early adipogenic factors such as CCAAT-enhancer binding proteins ß (C/EBPß), and Krüppel-like factors (KLFs) 4 and 5, while anti-early adipogenic factors, such as KLF2 and pref-1(preadipocyte factor-1), were upregulated. These kaempferol-mediated regulations of early adipogenic factors resulted in the attenuation of late adipogenic factors such as C/EBPα and peroxisome proliferator-activated receptor γ (PPARγ). These results were supported in zebrafish based on the decrease in lipid accumulation and expression of adipogenic factors. Our results indicated that kaempferol might have an anti-obesity effect by regulating lipid metabolism.
Assuntos
Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Quempferóis/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Peixe-Zebra/metabolismo , Células 3T3-L1 , Adipócitos/citologia , Animais , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Ciclo Celular/efeitos dos fármacos , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Regulação para Baixo/efeitos dos fármacos , Humanos , Camundongos , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismoRESUMO
SCOPE: Dieckol is a major polyphenol of Ecklonia cava. This study demonstrates a mechanistic role for dieckol in the suppression of lipid accumulation using three models. METHODS AND RESULTS: Mice were split into four experimental groups (n = 10 per group): normal diet, high-fat diet (HFD), and dieckol-supplemented diets. Dieckol-supplemented mice groups showed a significant decrease of body weight gain (38%) as well as fats of organs including epididymal (45%) compared with a HFD-fed group. LDL cholesterol level was reduced by 55% in dieckol-supplemented group. Adipogenic factors and lipid synthetic enzymes were analyzed via real-time PCR or immunoblotting. Dieckol regulated mRNA expressions of early adipogenic genes in 3T3-L1 cells. These results were reflected in downregulation of late adipogenic factors, resulting in a decrease in triacylglycerol content. These data were also verified in zebrafish and mouse models. Dieckol activated AMP-activated protein kinase α (AMPKα) signaling to inhibit lipid synthesis in 3T3-L1 and mouse model. Dieckol was also shown to inhibit mitotic clonal expansion via cell-cycle arrest. CONCLUSION: Our data demonstrate that dieckol inhibits lipid accumulation via activation of AMPKα signaling and cell-cycle arrest.
Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Adipócitos Brancos/metabolismo , Adipogenia , Benzofuranos/uso terapêutico , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais , Phaeophyceae/química , Células 3T3-L1 , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Proteínas Quinases Ativadas por AMP/química , Monofosfato de Adenosina/antagonistas & inibidores , Monofosfato de Adenosina/metabolismo , Adipócitos Brancos/citologia , Adipócitos Brancos/patologia , Animais , Fármacos Antiobesidade/metabolismo , Fármacos Antiobesidade/uso terapêutico , Antioxidantes/metabolismo , Antioxidantes/uso terapêutico , Benzofuranos/metabolismo , Pontos de Checagem do Ciclo Celular , Regulação da Expressão Gênica , Metabolismo dos Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Sobrepeso/etiologia , Sobrepeso/metabolismo , Sobrepeso/patologia , Sobrepeso/prevenção & controle , Subunidades Proteicas/agonistas , Subunidades Proteicas/metabolismo , Sistemas do Segundo Mensageiro , Peixe-ZebraRESUMO
Ellagic acid (EA) is a natural polyphenol found in various fruits and vegetables. In this study, we examined the inhibitory effect of EA on fat accumulation in 3T3-L1 cells during adipogenesis. Our data showed that EA reduced fat accumulation by down-regulating adipogenic markers such as peroxisome proliferator activated receptor γ (PPARγ) and the CCAAT/enhancer binding protein α (C/EBPα) at the mRNA and protein levels in a dose-dependent manner. We found that the decrease in adipogenic markers resulted from reduced expression of some early adipogenic transcription factors such as KLF4, KLF5, Krox20, and C/EBPß within 24 h. Also, these inhibitions were correlated with down-regulation of TG synthetic enzymes, causing inhibition of triglyceride (TG) levels in 3T3-L1 cells investigated by ORO staining and in zebrafish investigated by TG assay. Additionally, the cell cycle analysis showed that EA inhibited cell cycle progression by arresting cells at the G0/G1 phase.
Assuntos
Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular , Ácido Elágico/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Células 3T3-L1 , Animais , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/genética , Regulação para Baixo , Fator 4 Semelhante a Kruppel , Camundongos , PPAR gama/metabolismo , Polifenóis/farmacologia , Fatores de Transcrição/metabolismo , Peixe-ZebraRESUMO
Gelidium elegans is an edible red alga native to the intertidal area of northeastern Asia. We investigated the effect of G. elegans extract and its main flavonoids, rutin and hesperidin, on lipid accumulation and the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in 3T3-L1 and RAW264.7 cells. Our data show that G. elegans extract decreased lipid accumulation and ROS/RNS production in a dose-dependent manner. The extract also inhibited the mRNA expression of adipogenic transcription factors, such as peroxisome proliferator-activated receptor gamma and CCAAT/enhancer-binding protein alpha, while enhancing the protein expression of the antioxidant enzymes superoxide dismutases 1 and 2, glutathione peroxidase, and glutathione reductase compared with controls. In addition, lipopolysaccharide-induced nitric oxide production was significantly reduced in G. elegans extract-treated RAW264.7 cells. In analysis of the effects of G. elegans flavonoids on lipid accumulation and ROS/RNS production, only hesperidin showed an inhibitory effect on lipid accumulation and ROS production; rutin did not affect adipogenesis and ROS status. The antiadipogenic effect of hesperidin was evidenced by the downregulation of peroxisome proliferator-activated receptor gamma, CCAAT/enhancer-binding protein alpha, and fatty acid binding protein 4 gene expression. Collectively, our data suggest that G. elegans is a potential food source containing antiobesity and antioxidant constituents.