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1.
EMBO J ; 42(8): e112387, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-36872914

RESUMO

The cGAS-STING pathway plays an important role in host defense by sensing pathogen DNA, inducing type I IFNs, and initiating autophagy. However, the molecular mechanism of autophagosome formation in cGAS-STING pathway-induced autophagy is still unclear. Here, we report that STING directly interacts with WIPI2, which is the key protein for LC3 lipidation in autophagy. Binding to WIPI2 is necessary for STING-induced autophagosome formation but does not affect STING activation and intracellular trafficking. In addition, the specific interaction between STING and the PI3P-binding motif of WIPI2 leads to the competition of WIPI2 binding between STING and PI3P, and mutual inhibition between STING-induced autophagy and canonical PI3P-dependent autophagy. Furthermore, we show that the STING-WIPI2 interaction is required for the clearance of cytoplasmic DNA and the attenuation of cGAS-STING signaling. Thus, the direct interaction between STING and WIPI2 enables STING to bypass the canonical upstream machinery to induce LC3 lipidation and autophagosome formation.


Assuntos
Autofagossomos , Autofagia , Proteínas de Membrana , Autofagossomos/metabolismo , Autofagia/fisiologia , DNA/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Nucleotidiltransferases/metabolismo , Humanos
2.
J Cardiovasc Pharmacol ; 84(1): 45-57, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38922585

RESUMO

ABSTRACT: Atherosclerosis (AS) is a chronic progressive disease caused by various factors and causes various cerebrovascular and cardiovascular diseases (CVDs). Reducing the plasma levels of low-density lipoprotein cholesterol is the primary goal in preventing and treating AS. Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a crucial role in regulating low-density lipoprotein cholesterol metabolism. Panax notoginseng has potent lipid-reducing effects and protects against CVDs, and its saponins induce vascular dilatation, inhibit thrombus formation, and are used in treating CVDs. However, the anti-AS effect of the secondary metabolite, 20( S )-protopanaxatriol (20( S )-PPT), remains unclear. In this study, the anti-AS effect and molecular mechanism of 20( S )-PPT were investigated in vivo and in vitro by Western blotting, real-time polymerase chain reaction, enzyme-linked immunosorbent assay, immunofluorescence staining, and other assays. The in vitro experiments revealed that 20( S )-PPT reduced the levels of PCSK9 in the supernatant of HepG2 cells, upregulated low-density lipoprotein receptor protein levels, promoted low-density lipoprotein uptake by HepG2 cells, and reduced PCSK9 mRNA transcription by upregulating the levels of forkhead box O3 protein and mRNA and decreasing the levels of HNF1α and SREBP2 protein and mRNA. The in vivo experiments revealed that 20( S )-PPT upregulated aortic α-smooth muscle actin expression, increased the stability of atherosclerotic plaques, and reduced aortic plaque formation induced by a high-cholesterol diet in ApoE -/- mice (high-cholesterol diet-fed group). Additionally, 20( S )-PPT reduced the aortic expression of CD68, reduced inflammation in the aortic root, and alleviated the hepatic lesions in the high-cholesterol diet-fed group. The study revealed that 20( S )-PPT inhibited low-density lipoprotein receptor degradation via PCSK9 to alleviate AS.


Assuntos
Aorta , Doenças da Aorta , Aterosclerose , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Placa Aterosclerótica , Pró-Proteína Convertase 9 , Receptores de LDL , Sapogeninas , Animais , Aterosclerose/metabolismo , Aterosclerose/patologia , Aterosclerose/tratamento farmacológico , Aterosclerose/prevenção & controle , Aterosclerose/genética , Sapogeninas/farmacologia , Pró-Proteína Convertase 9/metabolismo , Pró-Proteína Convertase 9/genética , Receptores de LDL/genética , Receptores de LDL/metabolismo , Humanos , Masculino , Doenças da Aorta/patologia , Doenças da Aorta/prevenção & controle , Doenças da Aorta/metabolismo , Doenças da Aorta/genética , Doenças da Aorta/tratamento farmacológico , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aorta/patologia , Proteólise/efeitos dos fármacos , Células Hep G2 , Inibidores de PCSK9 , Transdução de Sinais/efeitos dos fármacos , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Camundongos , Dieta Hiperlipídica , Apolipoproteínas E
3.
Ren Fail ; 46(2): 2371988, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38952291

RESUMO

AIMS: Abnormal renal lipid metabolism causes renal lipid deposition, which leads to the development of renal fibrosis in diabetic kidney disease (DKD). The aim of this study was to investigate the effect and mechanism of chlorogenic acid (CA) on reducing renal lipid accumulation and improving DKD renal fibrosis. METHODS: This study evaluated the effects of CA on renal fibrosis, lipid deposition and lipid metabolism by constructing in vitro and in vivo models of DKD, and detected the improvement of Notch1 and Stat3 signaling pathways. Molecular docking was used to predict the binding between CA and the extracellular domain NRR1 of Notch1 protein. RESULTS: In vitro studies have shown that CA decreased the expression of Fibronectin, α-smooth muscle actin (α-SMA), p-smad3/smad3, alleviated lipid deposition, promoted the expression of carnitine palmitoyl transferase 1 A (CPT1A), and inhibited the expression of cholesterol regulatory element binding protein 1c (SREBP1c). The expression of Notch1, Cleaved Notch1, Hes1, and p-stat3/stat3 were inhibited. These results suggested that CA might reduce intercellular lipid deposition in human kidney cells (HK2) by inhibiting Notch1 and stat3 signaling pathways, thereby improving fibrosis. Further, in vivo studies demonstrated that CA improved renal fibrosis and renal lipid deposition in DKD mice by inhibiting Notch1 and stat3 signaling pathways. Finally, molecular docking experiments showed that the binding energy of CA and NRR1 was -6.6 kcal/mol, which preliminarily predicted the possible action of CA on Notch1 extracellular domain NRR1. CONCLUSION: CA reduces renal lipid accumulation and improves DKD renal fibrosis by inhibiting Notch1 and stat3 signaling pathways.


Assuntos
Ácido Clorogênico , Nefropatias Diabéticas , Fibrose , Rim , Metabolismo dos Lipídeos , Receptor Notch1 , Fator de Transcrição STAT3 , Transdução de Sinais , Fator de Transcrição STAT3/metabolismo , Receptor Notch1/metabolismo , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Animais , Transdução de Sinais/efeitos dos fármacos , Fibrose/tratamento farmacológico , Ácido Clorogênico/farmacologia , Ácido Clorogênico/uso terapêutico , Humanos , Camundongos , Masculino , Rim/patologia , Rim/efeitos dos fármacos , Rim/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Simulação de Acoplamento Molecular , Camundongos Endogâmicos C57BL , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Linhagem Celular
4.
Molecules ; 29(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731489

RESUMO

Gallic acid (GA) is a type of polyphenolic compound that can be found in a range of fruits, vegetables, and tea. Although it has been confirmed it improves non-alcoholic fatty liver disease (NAFLD), it is still unknown whether GA can improve the occurrence of NAFLD by increasing the low-density lipoprotein receptor (LDLR) accumulation and alleviating cholesterol metabolism disorders. Therefore, the present study explored the effect of GA on LDLR and its mechanism of action. The findings indicated that the increase in LDLR accumulation in HepG2 cells induced by GA was associated with the stimulation of the epidermal growth factor receptor-extracellular regulated protein kinase (EGFR-ERK1/2) signaling pathway. When the pathway was inhibited by EGFR mab cetuximab, it was observed that the activation of the EGFR-ERK1/2 signaling pathway induced by GA was also blocked. At the same time, the accumulation of LDLR protein and the uptake of LDL were also suppressed. Additionally, GA can also promote the accumulation of forkhead box O3 (FOXO3) and suppress the accumulation of hepatocyte nuclear factor-1α (HNF1α), leading to the inhibition of proprotein convertase subtilisin/kexin 9 (PCSK9) mRNA expression and protein accumulation. This ultimately results in increased LDLR protein accumulation and enhanced uptake of LDL in cells. In summary, the present study revealed the potential mechanism of GA's role in ameliorating NAFLD, with a view of providing a theoretical basis for the dietary supplementation of GA.


Assuntos
Ácido Gálico , Lipoproteínas LDL , Receptores de LDL , Humanos , Ácido Gálico/farmacologia , Receptores de LDL/metabolismo , Células Hep G2 , Lipoproteínas LDL/metabolismo , Receptores ErbB/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Pró-Proteína Convertase 9/metabolismo , Pró-Proteína Convertase 9/genética
5.
Angew Chem Int Ed Engl ; 62(18): e202300703, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-36808789

RESUMO

"Through space" palladium/hydrogen shift is an efficient strategy to achieve selective functionalization of a specific remote C-H bond. Compared with relatively extensive exploited 1,4-palladium migration process, the relevant 1,5-Pd/H shift was far less investigated. We herein report a novel 1,5-Pd/H shift pattern between a vinyl and an acyl group. Through the pattern, rapid access to 5-membered-dihydrobenzofuran and indoline derivatives has been achieved. Further studies have unveiled an unprecedented trifunctionalization (vinylation, alkynylation and amination) of a phenyl ring through 1,5-palladium migration relayed decarbonylative Catellani type reaction. A series of mechanistic investigations and DFT calculations have provided insights into the reaction pathway. Notably, it was unveiled that the 1,5-palladium migration in our case prefers a stepwise mechanism involving a PdIV intermediate.

6.
EMBO Rep ; 21(1): e48335, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31750630

RESUMO

Accumulating evidence highlights the role of histone acetyltransferase GCN5 in the regulation of cell metabolism in metazoans. Here, we report that GCN5 is a negative regulator of autophagy, a lysosome-dependent catabolic mechanism. In animal cells and Drosophila, GCN5 inhibits the biogenesis of autophagosomes and lysosomes by targeting TFEB, the master transcription factor for autophagy- and lysosome-related gene expression. We show that GCN5 is a specific TFEB acetyltransferase, and acetylation by GCN5 results in the decrease in TFEB transcriptional activity. Induction of autophagy inactivates GCN5, accompanied by reduced TFEB acetylation and increased lysosome formation. We further demonstrate that acetylation at K274 and K279 disrupts the dimerization of TFEB and the binding of TFEB to its target gene promoters. In a Tau-based neurodegenerative Drosophila model, deletion of dGcn5 improves the clearance of Tau protein aggregates and ameliorates the neurodegenerative phenotypes. Together, our results reveal GCN5 as a novel conserved TFEB regulator, and the regulatory mechanisms may be involved in autophagy- and lysosome-related physiological and pathological processes.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Proteínas de Drosophila/metabolismo , Histona Acetiltransferases/metabolismo , Lisossomos , Acetilação , Animais , Autofagossomos/metabolismo , Autofagia/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Drosophila , Lisossomos/metabolismo
7.
Anticancer Drugs ; 32(6): 647-656, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33587351

RESUMO

Triple-negative breast cancer (TNBC) is highly aggressive, with high rates of early relapse and very poor overall prognosis. Amphiregulin (AREG) is the most abundant epidermal growth factor receptor (EGFR) agonist in MDA-MB-231 TNBC cells, whose proliferation can be inhibited by (-)-epigallocatechin gallate (EGCG), a constituent of green tea that is prone to oxidative polymerization. The effect of dimeric-EGCG, a dimer of oxidized and polymerized EGCG, on MDA-MB-231 cell the proliferation warrants further exploration. In the present study, MTT, flow cytometry, migration scratch, transwell, western blotting, and surface plasmon resonance assays were used to evaluate the effect of dimeric-EGCG on MDA-MB-231 cells and explore the underlying mechanism. MDA-MB-231 cell proliferation and migration were significantly inhibited by dimeric-EGCG at concentrations as low as 10 µM. Levels of EGFR and p44/42 MAPK phosphorylation in MDA-MB-231 cells were significantly reduced by treatment with 10 µM dimeric-EGCG (P < 0.01). In addition, the levels of phosphorylation induced by exogenous AREG were also inhibited by dimeric-EGCG (P < 0.01); however, no significant effects of dimeric-EGCG were observed on epidermal growth factor or transforming growth factor-alpha signaling. Surface plasmon resonance analysis demonstrated that 10 µM dimeric-EGCG bound directly to the extracellular domain of EGFR, competitively inhibiting the binding of AREG to EGFR. These results suggest a novel mechanism underlying the inhibitory effect of dimeric-EGCG on MDA-MB-231 cells, with potential application in the development of drugs for the treatment of TNBC.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Catequina/análogos & derivados , Anfirregulina/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Catequina/química , Catequina/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dimerização , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Feminino , Humanos , Células MCF-7 , Transdução de Sinais/efeitos dos fármacos
8.
FASEB J ; 33(1): 953-964, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30070931

RESUMO

Delayed wound healing is one of the most prominent clinical manifestations of diabetes and lacks satisfactory treatment options. Persistent inflammation occurs in the late phase of wound healing and impairs the healing process in mice with diabetes mellitus (DM). In this study, we observed that the late wound healing in streptozotocin (STZ)-induced DM mice could be improved by (-)-epigallocatechin gallate (EGCG). The macrophage accumulation, inflammation response, and Notch signaling can be inhibited by EGCG in the skin wounds of DM mice. Furthermore, we found that the LPS-induced inflammation response including overactivated Notch signaling, was inhibited by EGCG in mouse macrophages. Moreover, we confirmed that EGCG could directly bind with mouse Notch-1. In addition, our studies indicated that diabetic wound healing was improved by EGCG treatment before or after the inflammation phase by targeting the Notch signaling pathway, which suggests that the pre-existing diabetic wound healing can be improved by EGCG. To summarize, wound healing can be improved by EGCG through targeting Notch in STZ-induced DM mice. Our findings provide insight into the therapeutic strategy for diabetic wounds and offer EGCG as a novel potential medicine to treat chronic wounds.-Huang, Y.-W., Zhu, Q.-Q., Yang, X.-Y., Xu, H.-H., Sun, B., Wang, X.-J., Sheng, J. Wound healing can be improved by (-)-epigallocatechin gallate through targeting Notch in streptozotocin-induced diabetic mice.


Assuntos
Catequina/análogos & derivados , Diabetes Mellitus Experimental/metabolismo , Receptores Notch/metabolismo , Cicatrização/efeitos dos fármacos , Animais , Catequina/farmacologia , Diabetes Mellitus Experimental/fisiopatologia , Feminino , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Células RAW 264.7 , Transdução de Sinais , Pele/metabolismo , Estreptozocina , Cicatrização/fisiologia
9.
Sensors (Basel) ; 19(1)2019 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-30621195

RESUMO

Autonomous parking in an indoor parking lot without human intervention is one of the most demanded and challenging tasks of autonomous driving systems. The key to this task is precise real-time indoor localization. However, state-of-the-art low-level visual feature-based simultaneous localization and mapping systems (VSLAM) suffer in monotonous or texture-less scenes and under poor illumination or dynamic conditions. Additionally, low-level feature-based mapping results are hard for human beings to use directly. In this paper, we propose a semantic landmark-based robust VSLAM for real-time localization of autonomous vehicles in indoor parking lots. The parking slots are extracted as meaningful landmarks and enriched with confidence levels. We then propose a robust optimization framework to solve the aliasing problem of semantic landmarks by dynamically eliminating suboptimal constraints in the pose graph and correcting erroneous parking slots associations. As a result, a semantic map of the parking lot, which can be used by both autonomous driving systems and human beings, is established automatically and robustly. We evaluated the real-time localization performance using multiple autonomous vehicles, and an repeatability of 0.3 m track tracing was achieved at a 10 kph of autonomous driving.

10.
J Cell Physiol ; 233(2): 924-935, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28369910

RESUMO

Binge drinking is associated with increased cardiac autophagy, and often triggers heart injury. Given the essential role of autophagy in various cardiac diseases, this study was designed to investigate the role of autophagy in ethanol-induced cardiac injury and the underlying mechanism. Our study showed that ethanol exposure enhanced the levels of LC3-II and LC3-II positive puncta and promoted cardiomyocyte apoptosis in vivo and in vitro. In addition, we found that ethanol induced autophagy and cardiac injury largely via the sequential triggering of reactive oxygen species (ROS) accumulation, activation of c-Jun NH2-terminal kinase (JNK), phosphorylation of Bcl-2, and dissociation of the Beclin 1/Bcl-2 complex. By contrast, inhibition of ethanol-induced autophagic flux with pharmacologic agents in the hearts of mice and cultured cells significantly alleviated ethanol-induced cardiomyocyte apoptosis and heart injury. Elimination of ROS with the antioxidant N-acetyl cysteine (NAC) or inhibition of JNK with the JNK inhibitor SP600125 reduced ethanol-induced autophagy and subsequent autophagy-mediated apoptosis. Moreover, metallothionein (MT), which can scavenge reactive oxygen and nitrogen species, also attenuated ethanol-induced autophagy and cell apoptosis in MT-TG mice. In conclusion, our findings suggest that acute ethanol exposure induced autophagy-mediated heart toxicity and injury mainly through the ROS-JNK-Bcl-2 signaling pathway.


Assuntos
Autofagia , Cardiomiopatia Alcoólica/enzimologia , Etanol , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Miócitos Cardíacos/enzimologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Cardiomiopatia Alcoólica/patologia , Cardiotoxicidade , Células Cultivadas , Modelos Animais de Doenças , Predisposição Genética para Doença , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Fenótipo , Inibidores de Proteínas Quinases/farmacologia , Ratos Sprague-Dawley , Transdução de Sinais , Fatores de Tempo
11.
J Sci Food Agric ; 98(6): 2312-2319, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28990656

RESUMO

BACKGROUND: Camellia sinensis var. assamica seed cake (a by-product of tea-seed oil) is an abundant resource with poor utilisation. C. sinensis var. assamica seed saponin (CSS) is one kind of non-ionic surfactant. In this study, the CSS extraction conditions were optimised by response surface methodology (RSM) and then the CSS detergent was developed. Additionally, the safety and decontamination ability of the developed detergent were evaluated. RESULTS: The optimised extraction conditions were including the extracting temperature of 40.04 °C, extraction time of 4.97 h, ethanol concentration of 64.11% and liquid-solid ratio of 14.57:1 mL g-1 . The formula of the CSS detergent was as follows: 20% crude CSS, 0.3% oxidised tea polyphenols (OTPs), 0.2% nisin, 0.3% sodium dehydroacetate, 0.7% sodium alginate and 0.5% sodium polyacrylate. The LD50 of the CSS detergent exceeds 14 g kg-1 in mice, indicating the detergent was non-toxic. Both of the emulsifying and the pesticide residues removal abilities of the CSS detergent were significantly stronger than the commercial detergent. CONCLUSION: A natural tea seed saponin detergent with good safety and decontamination ability was successfully developed. This can make better use of the tea seed cake, thereby creating added value in the tea seed oil industry. © 2017 Society of Chemical Industry.


Assuntos
Camellia sinensis/química , Detergentes/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Saponinas/isolamento & purificação , Detergentes/química , Extratos Vegetais/química , Polifenóis/química , Saponinas/análise , Saponinas/química , Sementes/química , Resíduos/análise
12.
Proteomics ; 17(12)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28467633

RESUMO

We report here a rapid and sensitive technique for negative visualization of protein in 1D and 2D SDS-PAGE by using 2', 7'-dichlorofluorescein (DCF), which appeared as transparent and colorless bands in an opaque gel matrix background. For DCF stain, down to 0.1-0.2 ng protein could be easily visualized within 7 min by only two steps, and the staining is fourfold more sensitive than that of Eosin Y (EY) negative stain and glutaraldehyde (GA) silver stain, and eightfold more sensitive than that of the commonly used imidazole-zinc (IZ) negative stain. Furthermore, DCF stain provided good reproducibility, linearity, and MS compatibility compared with those of IZ stain. In addition, the potential staining mechanism was investigated by colorimetric experiment and molecular docking, and the results demonstrated that the interaction between DCF and protein occurs mainly via van der waals force, electrostatic interaction, and hydrogen bonding.


Assuntos
Eletroforese em Gel de Poliacrilamida/métodos , Fluoresceínas/análise , Coloração Negativa/métodos , Proteínas/análise , Colorimetria/métodos , Humanos , Simulação de Acoplamento Molecular/métodos , Proteômica/métodos
13.
J Cell Mol Med ; 21(12): 3420-3434, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28643395

RESUMO

Catalase is an antioxidative enzyme that converts hydrogen peroxide (H2 O2 ) produced by superoxide dismutase from highly reactive superoxide (O2- ) to water and oxygen molecules. Although recent findings demonstrate that catalase, autophagy and the nuclear factor κB (NF-κB) signalling pathway are centrally involved in diabetic cardiomyopathy (DCM), the interplay between the three has not been fully characterized. Thus, the mechanism responsible for catalase-mediated protection against heart injury in diabetic mice was investigated in this study, as well as the role of NF-κB-p65 in the regulation of autophagic flux was investigated in this study. Western blot analysis revealed that catalase inhibited NF-κB activity and decreased LC3-II (microtubule-associated protein 1 light chain 3) and beclin-1 (Atg6) expression. Furthermore, up-regulation of autophagy was detrimental for cardiac function in diabetic mice. Catalase overexpression reduced the level of NF-κB subunit in the nucleus, where it initiates autophagy through activation of the key autophagy gene BECN1. To evaluate the role of the NF-κB pathway in diabetes-induced autophagy, Bay11-7082, an NF-κB inhibitor, was injected into diabetic mice, which suppressed NF-κB and attenuated diabetes-induced autophagy and myocardial apoptosis. In agreement with the in vivo results, Bay11-7082 also inhibited high-glucose-induced activation of NF-κB and the up-regulation of LC3-II and beclin-1 expression in H9c2 cells. In addition, high-glucose-induced activation of autophagic flux and apoptosis were largely attenuated by p65 siRNA, suggesting that catalase ameliorates diabetes-induced autophagy, at least in part by increasing the activity of the NF-κB pathway and p65-mediated transcription of BECN1.


Assuntos
Proteína Beclina-1/genética , Catalase/genética , Diabetes Mellitus Experimental/genética , Cardiomiopatias Diabéticas/genética , Proteínas Associadas aos Microtúbulos/genética , Fator de Transcrição RelA/genética , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Proteína Beclina-1/metabolismo , Catalase/metabolismo , Linhagem Celular , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Experimental/patologia , Cardiomiopatias Diabéticas/induzido quimicamente , Cardiomiopatias Diabéticas/enzimologia , Cardiomiopatias Diabéticas/patologia , Regulação da Expressão Gênica , Glucose/farmacologia , Masculino , Camundongos , Camundongos Transgênicos , Proteínas Associadas aos Microtúbulos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Nitrilas/farmacologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Estreptozocina , Sulfonas/farmacologia , Fator de Transcrição RelA/antagonistas & inibidores , Fator de Transcrição RelA/metabolismo , Transcrição Gênica
14.
Eur J Nutr ; 56(6): 2037-2048, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27271251

RESUMO

BACKGROUND: Tea polyphenols are the prominent component in tea. After the fermentation process, tea polyphenols are oxidized by polyphenol oxidase to form oxidized tea polyphenols (OTPs). OTPs contain a significant amount of hydrophobic phenyl groups that can bind with non-aqueous materials. Here, we determined whether OTPs can bind with lipids and reduce fat uptake and assessed the effect of OTPs on decreasing obesity and alleviating hyperlipidaemia and other metabolic syndromes. METHODS: Rats were divided into three groups: control, high-fat diet (HFD) and OTP groups. The control and HFD groups were fed a chow diet and a high-fat diet, respectively, for 12 weeks; the OTP group was fed a high-fat diet for 6 weeks and then a high-fat diet containing 2 % OTP for 6 weeks. The serum and excrement triglyceride (TAG) and total cholesterol (CHOL) concentrations were determined, and liver tissue and white adipose tissue were collected to detect the expression levels of genes involved in lipid metabolism. RESULTS: Our results revealed that OTPs failed to decrease the serum concentrations of TAG and CHOL. OTPs alleviated the accumulation of lipids in the liver tissue and changed the expression levels of the regulators of lipid metabolism, i.e., peroxisome proliferation-activated receptors (ppars), compared with the rats fed a high-fat diet alone. We also observed a significantly decreased reduction of weight in the visceral white adipose, enhanced regulation of fatty acid ß-oxidation by PPARα and enhanced biosynthesis of mitochondria in the visceral white adipose of the OTP rats compared with the HFD rats. Additionally, OTPs promoted the excretion of lipids. CONCLUSION: Our results suggest that OTPs alleviate the accumulation of lipids in liver and visceral white adipose tissue and promote lipid excretion in rats in vivo.


Assuntos
Gordura Intra-Abdominal/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Polifenóis/farmacologia , Chá/química , Animais , Biomarcadores/sangue , Colesterol/sangue , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Fezes/química , Hiperlipidemias/sangue , Hiperlipidemias/tratamento farmacológico , Gordura Intra-Abdominal/metabolismo , Fígado/metabolismo , Masculino , Obesidade/sangue , Obesidade/tratamento farmacológico , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Triglicerídeos/sangue
15.
Luminescence ; 32(7): 1307-1312, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28544697

RESUMO

A Schiff base compound derived from naphthalene has been synthesized and characterized as an Al3+ -selective fluorescent probe. The chemosensor (L) exhibits high selectively for Al3+ in aqueous solution, even in the presence of biologically relevant cations such as Na+ , K+ , Ca2+ , Mg2+ , Pb2+ and several transition metal ions. There was no observed interference from anions like Br- , Cl- , HSO3- , SO32- , S2 O32- , NO2- , CO32- and AC- . The lowest detection limit for the chemosensor L was found to be 1.89 × 10-8  M with a linear response towards Al3+ over a concentration range of 5 × 10-6 to 4 × 10-5  M. Furthermore, the proposed chemosensor has been used for imaging of Al3+ in two different types of cells with satisfying results, which further demonstrates its value for practical application in biological systems.


Assuntos
Alumínio/análise , Corantes Fluorescentes/química , Naftalenos/química , Espectrometria de Fluorescência/métodos , Animais , Corantes Fluorescentes/síntese química , Concentração de Íons de Hidrogênio , Limite de Detecção , Espectroscopia de Ressonância Magnética , Imagem Molecular/métodos , Estrutura Molecular , Células PC12 , Ratos , Bases de Schiff , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de Fourier
16.
J Sci Food Agric ; 97(6): 1910-1915, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27539359

RESUMO

BACKGROUND: Aflatoxin B1 (AFB1) is the most prevalent and carcinogenic form of the aflatoxins. In this report, we explored the interaction between AFB1 and oxidised tea polyphenols (OTP). Then, the influence of OTP on the absorption and toxicity of AFB1 in rats was investigated. RESULTS: We found that AFB1 can be complexed with OTP, and a transmembrane bidirectional transport experiment verified the absorption of complexed AFB1 (C-AFB1) was inhibited by OTP dramatically (P < 0.001). Animal experiments results showed that the AFB1 plus OTP group had significantly (P < 0.05) decreased AFB1-albumin (AFB1-alb) compared to the AFB1 group at 4 h after ingestion. OTP could significantly (P < 0.01) promote the elimination of AFB1 in faeces. Moreover, the liver injury induced by AFB1 was significantly inhibited by OTP. CONCLUSION: Our results demonstrated AFB1 can be complexed with OTP and the absorption of the C-AFB1 is inhibited in rats. Consequently, the liver injury induced by AFB1 can be inhibited by OTP. These results provide insight that consuming OTP-containing products, like fermented Pu-er tea, can protect damage from AFB1, and OTP may be used as a kind of food additive. © 2016 Society of Chemical Industry.


Assuntos
Aflatoxina B1/metabolismo , Preparações de Plantas/metabolismo , Polifenóis/metabolismo , Chá/metabolismo , Aflatoxina B1/toxicidade , Animais , Células CACO-2 , Humanos , Fígado/metabolismo , Masculino , Oxirredução , Ratos , Ratos Sprague-Dawley , Chá/química
17.
Molecules ; 21(5)2016 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-27187321

RESUMO

Epigallocatechin gallate (EGCG) is the most abundant component of green tea catechins and has strong physiological activities. In this study, two novel EGCG glycosides (EGCG-G1 and EGCG-G2) were chemoselectively synthesized by a chemical modification strategy. Each of these EGCG glycosides underwent structure identification, and the structures were assigned as follows: epigallocatechin gallate-4''-O-ß-d-glucopyranoside (EGCG-G1, 2) and epigallocatechin gallate-4',4''-O-ß-d-gluco-pyranoside (EGCG-G2, 3). The EGCG glycosides were evaluated for their anticancer activity in vitro against two human breast cell lines (MCF-7 and MDA-MB-231) using MTT assays. The inhibition rate of EGCG glycosides (EGCG-G1 and EGCG-G2) is not obvious. The EGCG glycosides are more stable than EGCG in aqueous solutions, but exhibited decreasing antioxidant activity in the DPPH radical-scavenging assay (EGCG > EGCG-G2 > EGCG-G1). Additionally, the EGCG glycosides exhibited increased water solubility: EGCG-G2 and EGCG-G1 were 15 and 31 times as soluble EGCG, respectively. The EGCG glycosides appear to be useful, and further studies regarding their biological activity are in progress.


Assuntos
Catequina/análogos & derivados , Glucose/metabolismo , Antioxidantes/farmacologia , Catequina/síntese química , Catequina/química , Catequina/farmacologia , Linhagem Celular Tumoral , Humanos
18.
BMC Complement Altern Med ; 15: 188, 2015 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-26084330

RESUMO

BACKGROUND: Insulin resistance is characterized by deficient responses to insulin in its target tissues. In the present study, we examined the effects of L-Citrulline (L-Cit) on insulin sensitivity and signaling cascades in rat hepatoma H4IIE cells and SHRSP.Z-Leprfa/IzmDmcr rats. METHODS: H4IIE cells were pretreated in the presence or absence of 250 µM L-Cit in serum-free medium and then incubated in the presence or absence of 0.1 nM insulin. Rats were allocated into 2 groups; a control group (not treated) and L-Cit group (2 g/kg/day, L-Cit) and treated for 8 weeks. RESULTS: L-Cit enhanced the insulin-induced phosphorylation of Akt in H4IIE cells. Moreover, the inhibited expression of Dex/cAMP-induced PEPCK mRNA by insulin was enhanced by the L-Cit treatment. The phosphorylation of tyrosine, which is upstream of Akt, in insulin receptor substrate-1 (IRS-1) was increased by the L-Cit treatment. The L-Cit-induced enhancement in insulin signaling was not related to the binding affinity of insulin to the insulin receptor or to the expression of the insulin receptor, but to a decrease in the phosphorylation of serine 1101 in IRS-1. These results were also confirmed in animal experiments. In the livers of L-Cit-treated rats, PI3K/Akt signaling was improved by decreases in the phosphorylation of serine 1101. CONCLUSIONS: We herein demonstrated for the first time the beneficial effects of L-Cit on improved insulin resistance associated with enhanced insulin sensitivity. These results may have clinical applications for insulin resistance and the treatment of type-2 diabetes.


Assuntos
Citrulina/farmacologia , Proteínas Substratos do Receptor de Insulina , Insulina/metabolismo , Fígado , Serina/metabolismo , Animais , Proteínas Substratos do Receptor de Insulina/química , Proteínas Substratos do Receptor de Insulina/efeitos dos fármacos , Proteínas Substratos do Receptor de Insulina/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fosforilação/efeitos dos fármacos , Ratos
19.
Biosens Bioelectron ; 259: 116378, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38759308

RESUMO

Physical and chemical signals in the central nervous system yield crucial information that is clinically relevant under both physiological and pathological conditions. The emerging field of bioelectronics focuses on the monitoring and manipulation of neurophysiological signals with high spatiotemporal resolution and minimal invasiveness. Significant advances have been realized through innovations in materials and structural design, which have markedly enhanced mechanical and electrical properties, biocompatibility, and overall device performance. The diagnostic and therapeutic potential of soft bioelectronics has been corroborated across a diverse array of pre-clinical settings. This review summarizes recent studies that underscore the developments and applications of soft bioelectronics in neurological disorders, including neuromonitoring, neuromodulation, tumor treatment, and biosensing. Limitations and outlooks of soft devices are also discussed in terms of power supply, wireless control, biocompatibility, and the integration of artificial intelligence. This review highlights the potential of soft bioelectronics as a future platform to promote deciphering brain functions and clinical outcomes of neurological diseases.


Assuntos
Técnicas Biossensoriais , Doenças do Sistema Nervoso , Humanos , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Doenças do Sistema Nervoso/diagnóstico , Animais , Desenho de Equipamento
20.
Food Funct ; 14(7): 3269-3278, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36916513

RESUMO

Increasing low-density lipoprotein receptor (LDLR) protein levels represents a key strategy for the prevention and treatment. Berberine can reportedly alleviate non-alcoholic fatty liver disease (NAFLD) by increasing the LDLR expression in an ERK1/2 signaling-dependent manner of NAFLD. Studies have shown that caffeine can inhibit fat deposition in the livers of mice; however, caffeine has not been reported to alleviate NAFLD by augmenting the LDLR expression via targeting EGFR. Here, an MTT assay, western blotting, RT-qPCR, immunohistochemistry, and surface plasmon resonance (SPR) analysis were used to investigate the role of caffeine in low-density lipoprotein cholesterol (LDL-C) clearance both in vitro and in vivo. In vitro, we found that caffeine could activate the EGFR-ERK1/2 signaling pathway in HepG2 cells, leading to increased LDLR mRNA and protein expression, and this effect could be inhibited by cetuximab. The SPR assay results have indicated that caffeine may increase the LDLR expression by directly binding to the EGFR extracellular domain and activating the EGFR-ERK1/2 signaling pathway. In vivo, caffeine markedly improved fatty liver and related blood indices in ApoE KO mice with high-fat-diet-induced NAFLD. Consistent with our in vitro results, we found that caffeine could also activate EGFR-ERK1/2 signaling and promote the LDLR expression in ApoE KO mice. In summary, caffeine can enhance the LDLR expression by directly binding to EGFR and activating the EGFR-ERK1/2 signaling pathway. EGFR signaling may represent a novel target for the prevention and treatment of NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Cafeína/farmacologia , Cafeína/metabolismo , Fígado/metabolismo , Receptores de LDL/genética , Receptores de LDL/metabolismo , LDL-Colesterol/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Apolipoproteínas E/genética , Camundongos Endogâmicos C57BL
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