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1.
J Ethnopharmacol ; 327: 117982, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38423411

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Cynanchum otophyllum C.K.Schneid.PI.Wilson, commonly referred as ''Qingyangshen'' (QYS), is a traditional folk medicine from Yunnan, renowned for its efficacy in neurological and psychiatric disorders. Glycosides isolated from QYS have shown promise in alleviating epilepsy, however, mechanisms of action and specific molecular targets remain to be elucidated. AIM OF THE STUDY: The study aimed to evaluate the anticonvulsant effects of Qingyangshen glycosides M1 (M1), a C21 steroidal glycoside from QYS, on pentylenetetrazol (PTZ)-induced convulsions in zebrafish (Danio rerio), and its neuroprotective effect on Glutamate (Glu)-induced damage to PC12 cells, and importantly to identify its potential molecular targets. MATERIALS AND METHODS: To evaluate anticonvulsant activity of M1, 7 days-post-fertilization (7-dpf) animals were pretreated (by immersion) and then exposed to PTZ (10 mM) solution. Furthermore, Glu-induced PC12 cell damage was employed to investigate the neuroprotective and anti-apoptotic capacity. Cells were pretreated with various concentrations of M1 (0-10 µM) for 12 h and then co-treated with Glu (15 mM) for an additional 24 h. The cell viability, apoptosis rate and apoptosis-related proteins (p-PI3K, PI3K, Akt, p-Akt, CREB, p-CREB, BDNF, Bax and Bcl-2) were measured using CCK-8, annexin V/PI and Western blot assays. To model the expected interaction between M1 and candidate cannabinoid receptor type 1 (CB1R), ERK phosphorylation, molecular docking, and drug affinity responsive target stability (DARTS) techniques were employed. Finally, CB1R antagonist Rimonabant (Rim) was validated by co-administration in both zebrafish and cells to confirm the requirement of CB1R for M1 efficacy. RESULTS: At a concentration of 400 µM, M1 dramatically reversed PTZ-induced convulsive-like behaviors in zebrafish, as evidenced by a significant reduction in locomotor activity. In the context of Glu-induced cytotoxicity, M1 (10 µM) demonstrated a notable increase in cell viability and suppressed apoptosis through modulation of the Bax/Bcl-2 ratio and activation of the PI3K/Akt/CREB/BDNF signaling axis. These effects were facilitated through CB1R activation. In contrast, Rim dampened the beneficial activities of M1 as a cannabinoid agonist. CONCLUSIONS: These results demonstrated that M1 as a potential CB1R activator, exhibiting anticonvulsive effects in a PTZ-induced zebrafish model and neuroprotective properties via the PI3K/Akt/CREB/BDNF signaling axis in a Glu-induced PC12 cell injury model. Notably, the observed seizure relief attenuated by CB1R chemical antagonism.


Assuntos
Fármacos Neuroprotetores , Proteínas Proto-Oncogênicas c-akt , Humanos , Ratos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Glicosídeos/farmacologia , Glicosídeos/uso terapêutico , Glicosídeos/química , Peixe-Zebra , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Proteína X Associada a bcl-2 , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Simulação de Acoplamento Molecular , China , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Convulsões/metabolismo , Proteínas Reguladoras de Apoptose , Apoptose , Proteínas Proto-Oncogênicas c-bcl-2 , Pentilenotetrazol/toxicidade , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico
2.
Chin J Integr Med ; 29(7): 644-654, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36809500

RESUMO

Chinese medicine (CM) is an important resource for human life understanding and discovery of drugs. However, due to the unclear pharmacological mechanism caused by unclear target, research and international promotion of many active components have made little progress in the past decades of years. CM is mainly composed of multi-ingredients with multi-targets. The identification of targets of multiple active components and the weight analysis of multiple targets in a specific pathological environment, that is, the determination of the most important target is the main obstacle to the mechanism clarification and thus hinders its internationalization. In this review, the main approach to target identification and network pharmacology were summarized. And BIBm (Bayesian inference modeling), a powerful method for drug target identification and key pathway determination was introduced. We aim to provide a new scientific basis and ideas for the development and international promotion of new drugs based on CM.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Humanos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Teorema de Bayes , Simulação de Acoplamento Molecular
3.
Insect Sci ; 29(5): 1287-1298, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35150068

RESUMO

Lytic polysaccharide monooxygenases (LPMOs) are important enzymes that boost the hydrolysis of recalcitrant polysaccharides, such as chitin. They are found extensively in different insect species and are classified as auxiliary activities family 15 (AA15) LPMOs (LPMO15). Some of them were identified from the insect midgut and proven to act on chitin. However, knowledge about their physiological roles during insect growth and development remains limited. Here, we found that midgut-specific LPMO15s are widely distributed in different insect orders, such as the orthopteran Locusta migratoria and the lepidopteran Bombyx mori. Using L. migratoria as a model insect, the function of midgut-specific LmLPMO15-3 during development was investigated. Double-stranded RNA-mediated downregulation of LmLPMO15-3 expression at the 4th or 5th instar nymph stage severely decreased the survival rate and resulted in lethal phenotypes. Hematoxylin and eosin staining results indicated that the deficient individuals exhibited incompletely digested peritrophic matrix (PM), which suggested that LmLPMO15-3 is essential for the deconstruction of the PM during molting. This study provides direct evidence of the physiological importance of a midgut-specific LPMO15 during insect development. As L. migratoria is one of the most destructive agricultural pests, LmLPMO15-3 is a potential target for pest management.


Assuntos
Locusta migratoria , Animais , Quitina/metabolismo , Amarelo de Eosina-(YS)/metabolismo , Hematoxilina/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Locusta migratoria/metabolismo , Oxigenases de Função Mista/metabolismo , RNA de Cadeia Dupla/metabolismo
4.
Front Psychiatry ; 12: 761964, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803770

RESUMO

Background: The rapid spread of Coronavirus Disease-19 (COVID-19) infection has been the most important public health crisis across the globe since the end of 2019. Anxiety and depression are the most common mental health problems among people during the pandemic, and many studies have reported anxiety and depressive symptoms in college students. However, information on the mental health status of international medical students during this critical period of time has been scarce, which hinders the efforts in making proper policy or strategies to help these students. The present study aims to explore the prevalence of anxiety and depressive symptoms in international medical students in China and to find out the factors that have potential predictive value for anxiety and depressive symptoms. Method: A cross-sectional study was carried out for international medical students during November 2020 at China Medical University in Shenyang, China. Five hundred and nineteen international students were interviewed with questionnaires containing demographic variables, Stressors in school, Generalized Anxiety Disorder Assessment (GAD-7), Patient Health Questionnaire-9 (PHQ-9), Simplified Coping Style Questionnaire (SCSQ), Perceived Stress Scale (PSS-10), the Multidimensional Scale of Perceived Social Support (MSPSS), Revised Life Orientation Test (LOT-R) and Resilience Scale-14 (RS-14). Univariate logistic regression and stepwise multiple logistic regression analyses were conducted where appropriate to explore the predictive factors of anxiety symptoms and depressive symptoms. Results: The prevalence of anxiety symptoms and depressive symptoms in the sample population was 28.5% (148/519) and 31.6% (164/519), respectively. Stressors in school (ß = 0.176, OR = 1.192, CI: 1.102-1.289), negative coping style (ß = 0.639, OR = 1.894, CI: 1.287-2.788) and perceived stress (ß = 0.230, OR = 1.258, CI: 1.184-1.337) were found to be the predictors of anxiety symptoms among the international medical students; while gender (ß = -0.594, OR = 0.552, CI: 0.315-0.968), stay up late (ß = 0.828, OR = 2.288, CI: 1.182-4.431), current place of residence (ß = 1.082, OR = 2.951, CI: 1.256-6.931), stressors in the school (ß = 0.303, OR = 1.354, CI: 1.266-1.496), negative coping style (ß = 0.866, OR = 2.377, CI: 1.516-3.725), perceived stress (ß = 0.233, OR = 1.262, CI: 1.180-1.351) were found to be predictors of depressive symptoms. Conclusion: The prevalence of anxiety symptoms and depressive symptoms was moderate among international medical students in China. The communal predictors of anxiety and depressive symptoms were stressors in school, negative coping style and perceived stress; while demographic factors such as gender (male), stay up late at night and current place of residence were found associated with depressive symptoms. These results suggest that proper stress management and specific interventions are needed to help students maintain their mental health during the COVID-19 pandemic period.

5.
Am J Physiol Cell Physiol ; 321(3): C429-C442, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34161152

RESUMO

The phosphatidylinositol 3-kinase-Akt signaling pathway plays an essential role in regulating cell proliferation and apoptosis. Akt kinase is at the center of this signaling pathway and interacts with a variety of proteins. Akt is overexpressed in almost 80% of tumors. However, inhibiting Akt has serious clinical side effects so is not a suitable treatment for cancer. During recent years, Akt scaffold proteins have received increasing attention for their ability to regulate Akt signaling and have emerged as potential targets for cancer therapy. In this paper, we categorize Akt kinase scaffold proteins into four groups based on their cellular location: membrane-bound activator and inhibitor, cytoplasm, and endosome. We describe how these scaffolds interact with Akt kinase, how they affect Akt activity, and how they regulate the specificity of Akt signaling. We also discuss the clinical application of Akt scaffold proteins as targets for cancer therapy.


Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Terapia de Alvo Molecular , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/genética , Trocadores de Sódio-Hidrogênio/genética , Trocadores de Sódio-Hidrogênio/metabolismo , Proteínas Ativadoras de ras GTPase/genética , Proteínas Ativadoras de ras GTPase/metabolismo
6.
Biosci Biotechnol Biochem ; 85(5): 1128-1139, 2021 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33693487

RESUMO

The C-terminal of G protein-coupled receptors is now recognized as being important for G protein activation and signaling function. To detect the role of C-terminal tail in receptor activation, we used the α1b-AR, which has a long C-terminal of 164 amino acids. We constructed the intramolecular FRET sensors, in which the C-terminal was truncated to 10 (∆C-10), 20 (∆C-20), 30 (∆C-30), 50 (∆C-50), 70 (∆C-70), or 90 (∆C-90). The truncated mutants of ∆C-10, ∆C-20, or ∆C-30 cannot induce FRET signal changes and downstream ERK1/2 phosphorylation. However, the truncated mutants of ∆C-50, ∆C-70, or ∆C-90 induce significant FRET signal changes and downstream ERK1/2 phosphorylation, especially ∆C-90. This is particularly true in the case of the ∆C-90, ∆C-70, or ∆C-50 which retained the potential phosphorylation sites (Ser401, Ser404, Ser408, or Ser410). The ∆C-90 showed an increase in agonist-induced FRET signal changes and ERK1/2 phosphorylation in PKC- or endocytosis-dependent and EGFR-, src-, or ß-arrestin2-independent.


Assuntos
Técnicas Biossensoriais , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Processamento de Proteína Pós-Traducional , Receptores Adrenérgicos alfa 1/química , beta-Arrestina 2/genética , Animais , Transferência Ressonante de Energia de Fluorescência , Expressão Gênica , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Mesocricetus , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , Fenilefrina/farmacologia , Fosforilação/efeitos dos fármacos , Plasmídeos/química , Plasmídeos/metabolismo , Domínios Proteicos , Engenharia de Proteínas/métodos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Receptores Adrenérgicos alfa 1/genética , Receptores Adrenérgicos alfa 1/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Serina/metabolismo , beta-Arrestina 2/antagonistas & inibidores , beta-Arrestina 2/metabolismo
7.
Carcinogenesis ; 42(4): 587-600, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33151304

RESUMO

c-Met hyperactivity has been observed in numerous neoplasms. Several researchers have shown that the abnormal activation of c-Met is mainly caused by transcriptional activation. However, the molecular mechanism behind this transcriptional regulation is poorly understood. Here, we suggest that Smad3 negatively regulates the expression and activation of c-Met via a transcriptional mechanism. We explore the molecular mechanisms that underlie Smad3-induced c-Met transcription inhibition. We found in contrast to the high expression of c-Met, Smad3 showed low protein and mRNA levels. Smad3 and c-Met expressions were inconsistent between lung cancer tissues and cell lines. We also found that Smad3 overexpression suppresses whereas Smad3 knockdown significantly promotes Epithelial-Mesenchymal Transition and production of the angiogenic factors VEGF, CTGF and COX-2 through the ERK1/2 pathway. In addition, Smad3 overexpression decreases whereas Smad3 knockdown significantly increases protein and mRNA levels of invasion-related ß-catenin and FAK through the PI3K/Akt pathway. Furthermore, using the chromatin immunoprecipitation analysis method, we demonstrate that a transcriptional regulatory complex consisting of HDAC1, Smad3 and mSin3A binds to the promoter of the c-Met gene. By either silencing endogenous mSin3A expression with siRNA or by pretreating cells with a specific HDAC1 inhibitor (MS-275), Smad3-induced transcriptional suppression of c-Met could be effectively attenuated. These results demonstrate that Smad3-induced inhibition of c-Met transcription depends on of a functional transcriptional regulatory complex that includes Smad3, mSin3A and HDAC1 at the c-Met promoter. Collectively, our findings reveal a new regulatory mechanism of c-Met signaling, and suggest a potential molecular target for the development of anticancer drugs.


Assuntos
Histona Desacetilase 1/genética , Neoplasias Pulmonares/genética , Complexo Correpressor Histona Desacetilase e Sin3/genética , Proteína Smad3/genética , Linhagem Celular Tumoral , Fator de Crescimento do Tecido Conjuntivo/genética , Ciclo-Oxigenase 2/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Pulmonares/patologia , Fosfatidilinositol 3-Quinases/genética , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas c-met/genética , Ativação Transcricional/genética , Fator A de Crescimento do Endotélio Vascular/genética , beta Catenina/genética
8.
Biochem Biophys Res Commun ; 514(4): 1217-1223, 2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31109650

RESUMO

The three mammalian Raf proteins (A-Raf, B-Raf, and C-Raf) are key components of the MAPK pathway. Although diverse functions have been proposed for Raf kinases, it is still not clear how interacting proteins contribute to differences in the signaling functions of the three Raf kinases. Here, we report the comparative interactomes of the three Raf kinases under serum-starved and EGF-stimulated conditions. We identified nearly 400 novel interacting proteins; some interacted with all three isoforms while others interacted exclusively with one or two. Comparing the interactomes of the three Raf kinases under different conditions revealed Raf proteins perform distinct functions through specific interactions. Our interactome data help define the differences between the three Raf kinases and may uncover new functions or regulatory mechanisms. Knowledge of Raf kinase protein-protein interactions will help us to investigate the function of specific pathways in the future.


Assuntos
Proteínas Proto-Oncogênicas B-raf/análise , Proteínas Proto-Oncogênicas c-raf/análise , Células HEK293 , Humanos , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas c-raf/metabolismo
9.
Sheng Li Xue Bao ; 70(5): 565-570, 2018 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-30377696

RESUMO

Son of sevenless homolog 1 (SOS1) protein is a ubiquitously expressed adapter. As a key protein in intracellular signaling, SOS1 plays an important role in many signal transduction pathways, such as Ras and Rac signaling pathways. The abnormal expression or mutation of SOS1 is closely related to clinical diseases. In this article, we review research progress on SOS1 functions and its roles in physiology and pathophysiology.


Assuntos
Proteína SOS1/fisiologia , Transdução de Sinais , Animais , Humanos , Mutação
10.
Mol Carcinog ; 57(10): 1396-1407, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29917268

RESUMO

Aberrant activation of the Raf-MEK-ERK pathway has frequently been associated with various cancers, especially lung cancer. However, the key regulators of this pathway are largely unknown. Using functional proteomics screening, we found that KAP1 interacts with c-Raf. Knocking out KAP1 decreased c-Raf phosphorylation at serine 259 and increased its phosphorylation at serine 338, which activated MEK and ERK. We detected higher KAP1 expression in lung cancer tissues than in normal peri-tumoral tissues. KAP1 knockdown arrested A549 lung cancer cells in the G0/G1 phase of the cell cycle and attenuated cell growth, metastasis, the epithelial-mesenchymal transition, angiogenesis, stemness, and colony formation. Furthermore, knocking out KAP1 remarkably increased the susceptibility of A549 cells to the anti-cancer drug 5-Fluorouracil, which correlated with increasing ERK phosphorylation. In vivo xenograft experiments suggested that KAP1 deficiency significantly decreases the tumorigenicity of A549 cells. Taken together, our findings indicate that KAP1 acts as a key module in the c-Raf-interactome complex and regulates lung cancer development through the Raf-MEK-ERK pathway. Therefore, KAP1 may represent a potential diagnosis biomarker and new treatment target for lung cancer.


Assuntos
Carcinogênese/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas Quinases/metabolismo , Transdução de Sinais , Proteína 28 com Motivo Tripartido/metabolismo , Células A549 , Antimetabólitos Antineoplásicos/farmacologia , Carcinogênese/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fluoruracila/farmacologia , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Transplante Heterólogo , Proteína 28 com Motivo Tripartido/genética , Quinases raf/metabolismo
11.
Biochim Biophys Acta Proteins Proteom ; 1866(8): 849-856, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29777862

RESUMO

A-Raf is a member of the Raf kinase family. Unlike B-Raf and C-Raf, the functions of A-Raf remain obscure. To gain more insight into the biological functions of A-Raf, we investigated the A-Raf interactome using proteomics. We found 132 proteins that interact with A-Raf and confirmed the interaction of 12 of these proteins with A-Raf by western blotting. Our data suggested that A-Raf regulates apoptosis, RNA catabolism, GTPase activity, and cell adhesion by interacting with proteins located in different cellular compartments. We identified all ten hallmarks of cancer in these interacting proteins, suggesting that A-Raf is involved in carcinogenesis. Our results also indicated that A-Raf may play a role in different diseases and signaling pathways. These findings have identified potential regulators of A-Raf and provide a systemic insight into its biological functions.


Assuntos
Proteômica , Proteínas Proto-Oncogênicas A-raf/metabolismo , Apoptose , Western Blotting , Carcinogênese/genética , Adesão Celular , GTP Fosfo-Hidrolases/metabolismo , Células HEK293 , Humanos , Imunoprecipitação , Domínios e Motivos de Interação entre Proteínas , Proteínas Proto-Oncogênicas A-raf/genética , RNA/metabolismo , Transdução de Sinais
12.
FEBS J ; 285(12): 2319-2336, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29701013

RESUMO

Activation of the histamine-3 receptor (H3R) is involved in memory processes and cognitive action, while blocking H3R activation can slow the progression of neurological disorders, such as Alzheimer's disease, schizophrenia and narcolepsy. To date, however, no direct way to examine the activation of H3R has been utilized. Here, we describe a novel biosensor that can visualize the activation of H3R through an intramolecular fluorescence resonance energy transfer (FRET) signal. To achieve this, we constructed an intramolecular H3R FRET sensor with cyan fluorescent protein (CFP) attached at the C terminus and yellow fluorescent protein (YFP) inserted into the third intracellular loop. The sensor was found to internalize normally on agonist treatment. We measured FRET signals between the donor CFP and the acceptor YFP in living cells in real time, the results of which indicated that H3R agonist treatment (imetit or histamine) increases the FRET signal in a time- and concentration-dependent manner with Kon and Koff values consistent with published data and which maybe correlated with decreasing cAMP levels and the promotion of ERK1/2 phosphorylation. The FRET signal was inhibited by H3R antagonists, and the introduction of mutations at F419A, F423A, L426A and L427A, once again, the promotion of ERK1/2 phosphorylation, was diminished. Thus, we have built a H3R biosensor which can visualize the activation of receptor through real-time structure changes and which can obtain pharmacological kinetic data at the same time. The FRET signals may allow the sensor to become a useful tool for screening compounds and optimizing useful ligands.


Assuntos
Técnicas Biossensoriais , Transferência Ressonante de Energia de Fluorescência/métodos , Agonistas dos Receptores Histamínicos/farmacologia , Antagonistas dos Receptores Histamínicos H3/farmacologia , Histamina/farmacologia , Receptores Histamínicos H3/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , AMP Cíclico/metabolismo , Expressão Gênica , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Imidazóis/farmacologia , Cinética , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Plasmídeos/química , Plasmídeos/metabolismo , Receptores Histamínicos H3/genética , Tioureia/análogos & derivados , Tioureia/farmacologia , Transfecção , Trítio
13.
Int J Biochem Cell Biol ; 99: 114-124, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29626639

RESUMO

The cannabinoid receptor 1 (CB1) is mainly expressed in the nervous system and regulates learning, memory processes, pain and energy metabolism. However, there is no way to directly measure its activation. In this study, we constructed a CB1 intramolecular fluorescence resonance energy transfer (FRET) sensor, which could measure CB1 activation by monitoring structural changes between the third intracellular loop and the C-terminal tail. CB1 agonists induced a time- and concentration-dependent increase in the FRET signal, corresponding to a reduction in the distance between the third intracellular loop and the C-terminal tail. This, in turn, mobilized intracellular Ca2+, inhibited cAMP accumulation, and increased phosphorylation of the ERK1/2 MAP kinases. The activation kinetics detected using this method were consistent with those from previous reports. Moreover, the increased FRET signal was markedly inhibited by the CB1 antagonist rimonabant, which also reduced phosphorylation of the ERK1/2 MAP kinases. We mutated a single cysteine residue in the sensor (at position 257 or 264) to alanine. Both mutation reduced the agonist-induced increase in FRET signal and structural changes in the CB1 receptor, which attenuated phosphorylation of the ERK1/2 MAP kinases. In summary, our sensor directly assesses the kinetics of CB1 activation in real-time and can be used to monitor CB1 structure and function.


Assuntos
Técnicas Biossensoriais , Agonistas de Receptores de Canabinoides/farmacologia , Antagonistas de Receptores de Canabinoides/farmacologia , Transferência Ressonante de Energia de Fluorescência/métodos , Regulação da Expressão Gênica/efeitos dos fármacos , Receptor CB1 de Canabinoide/química , Receptor CB1 de Canabinoide/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Cinética , Ligação Proteica
14.
Gene ; 656: 53-59, 2018 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-29499332

RESUMO

C-RAF was the first member of the RAF kinase family to be discovered. Since its discovery, C-RAF has been found to regulate many fundamental cell processes, such as cell proliferation, cell death, and metabolism. However, the majority of these functions are achieved through interactions with different proteins; the genes regulated by C-RAF in its active or inactive state remain unclear. In the work, we used RNA-seq analysis to study the global transcriptomes of C-RAF bearing or C-RAF knockout cells in quiescent or EGF activated states. We identified 3353 genes that are promoted or suppressed by C-RAF. Gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses revealed that these genes are involved in drug addiction, cardiomyopathy, autoimmunity, and regulation of cell metabolism. Our results provide a panoramic view of C-RAF function, including known and novel functions, and have revealed potential targets for elucidating the role of C-RAF.


Assuntos
Perfilação da Expressão Gênica , Proteínas Proto-Oncogênicas c-raf/fisiologia , Transcriptoma , Sequência de Bases , Técnicas de Inativação de Genes , Ontologia Genética , Células HEK293 , Humanos , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas c-raf/genética , RNA Mensageiro/genética , Análise de Sequência de RNA/métodos
15.
Biochem Biophys Res Commun ; 498(4): 932-939, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29545175

RESUMO

Lung cancer remains the leading cause of cancer-related deaths in the world. The RAF/MEK/ERK pathway controls many fundamental cellular functions and plays key roles in lung carcinogenesis. However, the proteins that regulate this pathway remain largely unknown. Here, we identified a novel C-RAF-binding protein, RUVBL1, which activates the RAF/MEK/ERK pathway by inhibiting phosphorylation of the C-RAF protein at serine 259. RUVBL1 expression was elevated in lung adenocarcinoma tissues. In addition, knocking out RUVBL1 effectively inhibited the proliferation and invasion of A549 cells. In vivo experiments, RUVBL1 deficiency significantly decreased the tumorigensis of lung cancer. In conclusion, we have shown that RUVBL1 could activate the RAF/MEK/ERK pathway by inhibiting phosphorylation of the C-RAF protein at serine 259, to promote lung cancer progression. Therefore, RUVBL1 could represent a novel therapeutic target for lung cancer treatment.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/fisiologia , Carcinogênese/metabolismo , Proteínas de Transporte/fisiologia , DNA Helicases/fisiologia , Neoplasias Pulmonares/etiologia , Sistema de Sinalização das MAP Quinases , Proteínas Proto-Oncogênicas c-raf/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células A549 , ATPases Associadas a Diversas Atividades Celulares/farmacologia , Carcinogênese/efeitos dos fármacos , Proteínas de Transporte/farmacologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , DNA Helicases/farmacologia , Humanos , Fosforilação/efeitos dos fármacos , Células Tumorais Cultivadas
16.
Cell Biol Int ; 42(7): 756-768, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29418027

RESUMO

The c-Jun N-terminal kinases (JNKs) are located downstream of Ras-mitogen activated protein kinase signaling cascades. More than 20 years of study has shown that JNKs control cell fate and many cellular functions. JNKs and their interacting proteins form a complicated network with diverse biological functions and physiological effects. Members of the JNK interactome include Jun, amyloid precursor protein, and insulin receptor substrate. Recent studies have shown that the JNK interactome is involved in tumorigenesis, neuron development, and insulin resistance. In this review, we summarize the features of the JNK interactome and classify its members into three groups: upstream regulators, downstream effectors, and scaffold partners. We also highlight the unique cellular signaling mechanisms of JNKs and provide more insights into the roles of the JNK interactome in human diseases.


Assuntos
Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Transdução de Sinais/fisiologia , Proteínas ras/metabolismo , Animais , Saúde , Humanos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
17.
Sci Total Environ ; 619-620: 1661-1672, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29089138

RESUMO

Shallow lakes are vulnerable to eutrophication because of abundant phytoplankton and significant nutrient input from sediments. Previous studies have researched the effect of environmental factors on phytoplankton and phosphorus release from sediment. However, few studies have simultaneously evaluated the interactive effects of environmental factors on phytoplankton communities and the interactions among different sediment nutrients. This paper reports on a 2016 investigation that examined the phytoplankton community and physical and chemical factors in both the water column and sediments in a Chinese shallow lake and its adjoining rivers. Our results indicated that rivers with water gates and lake areas had greater Chlorophyll a concentrations (Chl a) than natural rivers with similar total phosphorus (TP) concentrations; this indicates the importance of residence time on phytoplankton biomass. Although temperature impacted Chl a less than nutrients, its effects were highly species-specific, modulating relationships between nutrients and the abundance of different phytoplankton taxa. The effects of nutrients changed based on phytoplankton biomass and community composition, suggesting that different phytoplankton taxa have different nutrient demands. We predict that increasing residence time, temperature, and nutrients will increase phytoplankton biomass and increase the future dominance of Chlorophyta and Cyanophyta. In the interstitial water, there were no significant seasonal differences in TP, total nitrogen, and soluble reactive silica concentrations. However, ammonia concentrations were higher in the spring and lower in other seasons; nitrate and sulfate were abundant when the ammonia concentration was low. The total iron level in sediments was significantly negatively related with TP at low ammonia and silica concentrations and at high nitrate and sulfate concentrations in the interstitial water. These results indicated that nutrients are closely coupled in the sediments, highlighting the importance of oxidation-reduction potentials on internal nutrient balance.


Assuntos
Eutrofização , Lagos , Fitoplâncton/crescimento & desenvolvimento , Rios , Biomassa , China , Clorofila/análise , Clorofila A , Nitratos/análise , Nitrogênio/análise , Fósforo/análise , Estações do Ano , Dióxido de Silício/análise , Sulfatos/análise
18.
RSC Adv ; 8(70): 40471-40482, 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-35558242

RESUMO

A microwave processing technology was applied to degrade saponins from the stems and leaves of Panax notoginseng. Six transformation products (1-6), named 20(S)-ginsenoside Rg3 (1), 20(R)-ginsenoside Rg3 (2), notoginsenoside SFt3 (3), ginsenoside Rk1 (4), ginsenoside Rg5 (5), and 20(S)-ginsenoside Rh2 (6) were isolated and identified from a microwave processed extract of the stems and leaves of P. notoginseng (MEL). This transformation method was also applied for producing the minor ginsenosides in flowers, seeds and pedicels of P. notoginseng. The extract and compounds 1-6 in MEL were evaluated in vitro for anticancer and anticoagulant activities. The results showed that the MEL extract and transformation products had outstanding inhibitory activities against human cervical cancer Hela and lung cancer A549 cells. The strongest inhibitory effect was observed for 20(S)-Rh2 (6) with an IC50 value of 8.23 µM in Hela cells. Moreover, the results showed that the MEL significantly prolonged prothrombin time in a concentration-dependent manner. The anticoagulant effect of the MEL improved with the increased contents of Rk1, Rg5, and SFt3.

19.
Oncotarget ; 8(40): 68329-68337, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28978120

RESUMO

Raf1 is a member of the Raf kinase family and regulates many fundamental cell processes, including proliferation, differentiation, apoptosis, motility, and metabolism. However, the functions of Raf1 have not been completely elucidated. To better understand Raf1 function, we investigated the proteins that interacted with Raf1. We identified 198 Raf1 interacting proteins and our data suggested that Raf1 may regulate cell processes through these interactions. These interaction partners were involved in all ten hallmarks of cancer, suggesting that Raf1 is involved in different aspects of carcinogenesis. In addition, we showed that Raf1 interacting proteins were enriched in six signaling pathways and many human diseases. The interaction partners identified in this study may represent oncological candidates for future investigations into Raf1 function. Our findings have provided an overview of Raf1 function from a systems biology perspective.

20.
Food Chem ; 229: 458-463, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28372201

RESUMO

Formaldehyde abuse for retaining squid freshness is detrimental to public health. The aim is to establish a rapid and quantitative detection method of formaldehyde in squid for screening massive samples. A linear relationship between formaldehyde concentration in squid and formaldehyde concentration in squid soaked water was observed using HPLC. Chemical profile variances of squids were rapidly analyzed by Tri-step infrared spectroscopy. Specifically, with increasing formaldehyde concentration, peak intensities of 2927cm-1 (vas(CH2)), 1081cm-1 (glycogen), 1631cm-1 (ß-sheet proteins) decreased while 1655cm-1 (α-helix proteins) increased. Spectral curve-fitting results further disclosed that ß-sheet proteins were transformed to α-helix and ß-turn conformations. Furthermore, a quantitative prediction model based on IR spectra was established by PLS (R2, 0.9787; RMSEC, 5.51). The developed method was applicable for rapid (c.a. 5min) and quantitative analysis of formaldehyde in squids with LOD of 15mg/kg.


Assuntos
Decapodiformes/química , Contaminação de Alimentos/análise , Formaldeído/análise , Espectrofotometria Infravermelho/métodos , Animais , Análise dos Mínimos Quadrados , Limite de Detecção
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