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1.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(7): 619-624, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31537247

RESUMO

Objective To investigate the effects of Astragalus polysaccharide (APS) on autophagy and expression of microtubule-associated protein 1 light chain 3B (LC3B), mammalian target of rapamycin (mTOR) and beclin1 in xanthine oxidase (XOD)-induced autophagic model of non-small cell lung cancer A549 cells. Methods A549 cells were divided into five groups: control group, model group, 100, 200 and 400 µg/mL APS-treated group. Except for control group, all groups were administered XOD for 24 hours to establish autophagic models. Morphology of autophagosome was detected by transmission electron microscopy (TEM) and the number was counted by monodansylcadaverine (MDC) staining. The expression levels of LC3B, beclin1 and mTOR were detected by Western blot analysis. Results Compared with the control group, the number of autophagosome in the model group increased; the expression of LC3B and beclin1 significantly increased; while the expression of mTOR significantly decreased. Compared with the model group, the number of autophagosome decreased remarkably; the expression of LC3B and beclin1 severely decreased, and the expression of mTOR obviously increased in 200 or 400 µg/mL APS-treated group. Conclusion APS reduces the level of autophagy, down-regulates the expression of LC3B and beclin1, and increases mTOR expression in the autophagic model of A549 cells induced by XOD.


Assuntos
Astrágalo (Planta)/química , Autofagia , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Polissacarídeos/farmacologia , Células A549 , Proteínas Relacionadas à Autofagia , Proteína Beclina-1/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Xantina Oxidase
2.
Adv Exp Med Biol ; 1155: 923-934, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31468457

RESUMO

Diabetic neuropathy (DN) is the most common chronic complication of DM and its major pathological changes show axonal dysfunction, atrophy and loss. However, there are few reports that taurine promotes neurite growth of dorsal root ganglion (DRG) cells. In current study, DRG neurons were exposed to high glucose (HG) with or without taurine. The neurite outgrowth of DRG neurons was observed by fluorescent immunohistochemistry method. Expression of Gap-43, Akt, phosphorylated Akt, mTOR and phosphorylated mTOR was determined by Western blot assay. Our results showed that HG significantly decreased the neurite outgrowth and expression of Gap-43 in DRG neurons. Moreover, phosphorylated levels of Akt and mTOR were downregulated in DRG neurons exposed to HG. On the contrary, taurine supplementation significantly reversed the decreased neurite outgrowth and Gap-43 expression, and the downregulated phosphorylated levels of Akt and mTOR. However, the protective effects of taurine were blocked in the presence of PI3K antagonists LY294002 or Akt antagonists Perifosine. These results indicate that taurine promotes neurite outgrowth of DRG neurons exposed to HG via activating Akt/mTOR signal pathway.


Assuntos
Gânglios Espinais/citologia , Neurônios/efeitos dos fármacos , Taurina/farmacologia , Células Cultivadas , Proteína GAP-43/metabolismo , Glucose , Humanos , Neuritos/efeitos dos fármacos , Neurônios/citologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo
3.
Biol Res ; 52(1): 44, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31426858

RESUMO

BACKGROUND: Free fatty acid receptor 1 (FFAR1) is G-protein coupled receptor predominantly expressed in pancreatic ß-cells that is activated by a variety of free fatty acids (FFAs). Once activated, it promotes glucose-stimulated insulin secretion (GSIS). However, increased levels of FFAs lead to lipotoxicity, inducing loss of ß-cell function. FFAR1 plays a key role in the development of type 2 diabetes (T2D), and previous studies have indicated the importance of developing anti-diabetic therapies against FFAR1, although its role in the regulation of ß-cell function remains unclear. The present study investigated the role of FFAR1 under lipotoxic conditions using palmitic acid (PA). The rat insulinoma 1 clone 832/13 (INS-1 832/13) cell line was used as a model as it physiologically resembles native pancreatic ß-cells. Key players of the insulin signaling pathway, such as mTOR, Akt, IRS-1, and the insulin receptor (INSR1ß), were selected as candidates to be analyzed under lipotoxic conditions. RESULTS: We revealed that PA-induced lipotoxicity affected GSIS in INS-1 cells and negatively modulated the activity of both IRS-1 and Akt. Reduced phosphorylation of both IRS-1 S636/639 and Akt S473 was observed, in addition to decreased expression of both INSR1ß and FFAR1. Moreover, transient knockdown of FFAR1 led to a reduction in IRS-1 mRNA expression and an increase in INSR1ß mRNA. Finally, PA affected localization of FFAR1 from the cytoplasm to the perinucleus. CONCLUSIONS: In conclusion, our study suggests a novel regulatory involvement of FFAR1 in crosstalk with mTOR-Akt and IRS-1 signaling in ß-cells under lipotoxic conditions.


Assuntos
Células Secretoras de Insulina/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Ácido Palmítico/toxicidade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Apoptose , Linhagem Celular , Células Secretoras de Insulina/metabolismo , Ratos , Transdução de Sinais
4.
Chem Biol Interact ; 311: 108793, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31421117

RESUMO

Polyphyllin I (PPI), a bioactive component extracted from Paris polyphylla, was reported to have potent anticancer activities in previous studies. However, there were few reports on the effects and underlying mechanism of PPI in human acute myeloid leukemia cells. The present study demonstrated that PPI had an inhibitory effect through inducing apoptosis and autophagy in THP-1 and NB4 cells. PPI induced apoptosis via activating JNK pathway, as evidenced by the decreased Bcl-2 levels and increased Bax, cleaved-caspase-3 and phosphorylated-JNK expressions. In addition, PPI promoted autophagy as evidenced with increased expressions of LC3-II and Beclin-1 in western blot and autophagic vacuoles in MDC staining, which was associated with the inhibition of AKT-mTOR pathway. Furthermore, JNK inhibitor SP600125 and autophagy inhibitor 3-MA were employed to evaluate the role of apoptosis and autophagy in PPI-induced cell death. We found that autophagy and apoptosis were both causes of cell death induced by PPI. These data suggested that PPI could be a potent therapeutic agent for the treatment of human acute myeloid leukemia.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Diosgenina/análogos & derivados , Transdução de Sinais/efeitos dos fármacos , Caspase 3/metabolismo , Linhagem Celular Tumoral , Diosgenina/farmacologia , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Leucemia Mieloide Aguda/patologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Regulação para Cima/efeitos dos fármacos
5.
Adv Exp Med Biol ; 1152: 283-292, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31456190

RESUMO

Based on the insights gleaned from decades of research, it seems clear that mechanistic target of rapamycin (mTOR) is an essential signaling node that integrates environmental clues for regulation of cell survival, metabolism and proliferation of the cells. However, overwhelmingly increasing scientific evidence has added a new layer of intricacy to already complicated and versatile signaling pathway of mTOR. Deregulation of spatio-temporally controlled mTOR-driven pathway played contributory role in breast cancer development and progression. Pharmacologists and molecular biologists have specifically emphasized on the identification and development of mTOR-pathway inhibitors. In this chapter we have attempted to provide an overview of the most recent findings related to therapeutic targeting of mTOR-associated mTORC1 and mTORC2 in breast cancer. We have also comprehensively summarized regulation of mTOR and its partners by microRNAs in breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Feminino , Humanos , MicroRNAs/genética , Terapia de Alvo Molecular , Metástase Neoplásica
6.
Cell Physiol Biochem ; 53(2): 301-322, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31343125

RESUMO

BACKGROUND/AIMS: Propolis is one of the most promising natural products, exhibiting not only therapeutic but also prophylactic actions. Propolis has several biological and pharmacological properties, including hepatoprotective activities. The present study aimed to investigate the underlying molecular mechanisms of propolis against CCl4-mediated liver fibrosis. METHODS: Three groups of male BALB/c mice (n=15/ group) were used: group 1 comprised control mice; groups 2 and 3 were injected with CCl4 for the induction of liver fibrosis. Group 3 was then orally supplemented with propolis (100 mg/kg body weight) for four weeks. Different techniques were used to monitor the antifibrotic effects of propolis, including histopathological investigations using H&E, Masson's trichrome and Sirius red staining; Western blotting; flow cytometry; and ELISA. RESULTS: We found that the induction of liver fibrosis by CCl4 was associated with a significant increase in hepatic collagen and α-smooth muscle actin (α-SMA) expression. Moreover, CCl4-treated mice also exhibited histopathological alterations in the liver architecture. Additionally, the liver of CCl4-treated mice exhibited a marked increase in proinflammatory signals, such as increased expression of HSP70 and increased levels of proinflammatory cytokines and ROS. Mechanistically, the liver of CCl4-treated mice exhibited a significant increase in the phosphorylation of AKT and mTOR; upregulation of the expression of BAX and cytochrome C; downregulation of the expression of Bcl2; a significant elevation in the levels of TGF-ß followed by increased phosphorylation of SMAD2; and a marked increase in the expression of P53 and iNOS. Interestingly, oral supplementation of CCl4-treated mice with propolis significantly abolished hepatic collagen deposition, abrogated inflammatory signals and oxidative stress, restored CCl4-mediated alterations in the signaling cascades, and hence repaired the hepatic architecture nearly to the normal architecture observed in the control mice. CONCLUSION: Our findings revealed the therapeutic potential and the underlying mechanisms of propolis against liver fibrosis.


Assuntos
Apoptose/efeitos dos fármacos , Cirrose Hepática Experimental/patologia , Própole/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Tetracloreto de Carbono/toxicidade , Citocinas/metabolismo , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico Sintase Tipo II/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína Smad2/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo
7.
Life Sci ; 232: 116613, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31265853

RESUMO

AIMS: Sepsis is a leading cause of death and disability worldwide. Autophagy may play a protective role in sepsis-induced myocardial dysfunction (SIMD). The present study investigated whether valproic acid (VPA), a class I histone deacetylase (HDAC) inhibitor, can attenuate SIMD by accelerating autophagy. MAIN METHODS: A sepsis model was established via the cecum ligation and puncture of male Sprague-Dawley rats. Cardiac injuries were measured using serum markers, echocardiographic cardiac parameters, and hematoxylin and eosin staining. Cardiac mitochondria injuries were detected with transmission electron microscopy, adenosine triphosphate (ATP) and cardiac mitochondrial DNA (mtDNA) contents. Cardiac oxidative levels were measured using redox markers in the cardiac homogenate. Real-time polymerase chain reaction (RT-PCR) and Western blot were performed to detect the expression levels of relative genes and proteins. HDAC binding to the phosphatase and tensin homolog deleted on chromosome ten (PTEN) promoters and histone acetylation levels of the PTEN promoters were analyzed via chromatin immunoprecipitation and quantitative RT-PCR. KEY FINDINGS: VPA can ameliorate SIMD by enhancing the autophagy level of the myocardium to reduce mitochondrial damage, oxidative stress, and myocardial inflammation in septic rats. Moreover, this study demonstrated that VPA induces autophagy by inhibiting HDAC1- and HDAC3-mediated PTEN expression in the myocardial tissues of septic rats. SIGNIFICANCE: This study found that VPA attenuates SIMD through myocardial autophagy acceleration by increasing PTEN expression and inhibiting the AKT/mTOR pathway. These findings preliminarily suggest that VPA may be a potential approach for the intervention and treatment of SIMD.


Assuntos
PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sepse/tratamento farmacológico , Serina-Treonina Quinases TOR/metabolismo , Ácido Valproico/farmacologia , Disfunção Ventricular/tratamento farmacológico , Animais , Autofagia/efeitos dos fármacos , Ceco/metabolismo , Modelos Animais de Doenças , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Masculino , Miocárdio/metabolismo , Ratos , Ratos Sprague-Dawley , Sepse/fisiopatologia , Transdução de Sinais/efeitos dos fármacos , Disfunção Ventricular/microbiologia , Disfunção Ventricular/patologia
8.
Chem Biol Interact ; 310: 108726, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31255635

RESUMO

Tetrandrine (TET) and cepharanthine (CEP) are two bisbenzylisoquinoline alkaloids isolated from the traditional herbs. Recent molecular investigations firmly supported that TET or CEP would be a potential candidate for cancer chemotherapy. Prognosis of patients with glucocorticoid resistant T cell acute lymphoblastic leukemia (T-ALL) remains poor; here we examined the anti-T-ALL effects of TET and CEP and the underlying mechanism by using the glucocorticoid resistant human leukemia Jurkat T cell line in vitro. TET and CEP significantly inhibited cell viabilities and induced apoptosis in dose- and time-dependent manner. Further investigations showed that TET or CEP not only upregulated the expression of initiator caspases such as caspase-8 and 9, but also increased the expression of effector caspases such as caspase-3 and 6. As the important markers of apoptosis, p53 and Bax were both upregulated by the treatment of TET and CEP. However, TET and CEP paradoxically increased the expression of anti-apoptotic proteins such as Bcl-2 and Mcl-1, and activated the survival protein NF-κB, leading to high expression of p-NF-κB. Cell cycle arrest at S phase accompanied by increase in the amounts of cyclin A2 and cyclin B1, and decrease in cylcin D1 amount in cells treated with TET or CEP will be another possible mechanism. During the process of apoptosis in Jurkat T cells, treatment with TET or CEP also increased the phosphorylation of JNK and p38. The PI3K/Akt/mTOR signaling pathway modification appears to play significant role in the Jurkat T cell apoptosis induced by TET or CEP. Moreover, TET and CEP seemed to downregulate the expressions of p-PI3K and mTOR in an independent way from Akt, since these two drugs strongly stimulated the p-Akt expression. These results provide fundamental insights into the clinical application of TET or CEP for the treatment of patients with relapsed T-ALL.


Assuntos
Apoptose/efeitos dos fármacos , Benzilisoquinolinas/farmacologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Benzilisoquinolinas/uso terapêutico , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Humanos , Células Jurkat , Sistema de Sinalização das MAP Quinases , Fosfatidilinositol 3-Quinases/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
9.
Life Sci ; 233: 116696, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31351969

RESUMO

AIMS: To explore the mechanism of how LSD1 regulates autophagy and the correlation between LSD1 and Ox-LDL-induced inflammation. MAIN METHODS: RAW264.7 cells were used during the whole study. Firstly, the effect of Ox-LDL-stimulation on LSD1 expression was detected. Through loss-of-function assay, the associations between LSD1 interference and SESN2 expression, autophagy, NLRP3 inflammasome and inflammatory cytokines were explored. Finally, the function of LSD1 exerted on activation of PI3K/Akt/mTOR signal pathway was detected using western blotting assay. KEY FINDINGS: The expression of LSD1 was significantly elevated in Ox-LDL-treated RAW264.7 cells. Inhibition of LSD1 promoted autophagy, inhibited inflammation and activated NLRP3 inflammasome. SESN2 was elevated by LSD1 inhibition, and thus activate the PI3K/Akt/mTOR signal pathway. What' more, Knockdown of SESN2 or deactivate the PI3K/Akt/mTOR signal pathway partly reversed the effect of LSD1 inhibition on autophagy. SIGNIFICANCE: Our present study drew the finding that the knockdown of LSD1 meliorated Ox-LDL-stimulated NLRP3 activation and inflammation through promoting autophagy via SESN2-mediated PI3K/Akt/mTOR pathway.


Assuntos
Autofagia , Regulação da Expressão Gênica/efeitos dos fármacos , Histona Desmetilases/metabolismo , Inflamação/patologia , Lipoproteínas LDL/efeitos adversos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas Nucleares/metabolismo , Animais , Células Cultivadas , Histona Desmetilases/antagonistas & inibidores , Histona Desmetilases/genética , Inflamação/etiologia , Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteínas Nucleares/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
10.
Adv Exp Med Biol ; 1143: 1-39, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31338813

RESUMO

Hematopoietic stem cells (HSCs) and leukemic stem cells (LSCs) utilize many of the same signaling pathways for their maintenance and survival. In this review, we will focus on several signaling pathways whose roles have been extensively studied in both HSCs and LSCs. Our main focus will be on the PI3K/AKT/mTOR pathway and several of its regulators and downstream effectors. We will also discuss several other signaling pathways of particular importance in LSCs, including the WNT/ß-catenin pathway, the NOTCH pathway, and the TGFß pathway. For each of these pathways, we will emphasize differences in how these pathways operate in LSCs, compared to their function in HSCs, to highlight opportunities for the specific therapeutic targeting of LSCs. We will also highlight areas of crosstalk between multiple signaling pathways that may affect LSC function.


Assuntos
Células-Tronco Hematopoéticas , Células-Tronco Neoplásicas , Transdução de Sinais , Células-Tronco Hematopoéticas/fisiologia , Humanos , Células-Tronco Neoplásicas/fisiologia , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Serina-Treonina Quinases TOR/metabolismo
11.
Nat Commun ; 10(1): 2943, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31270333

RESUMO

Mutations exclusively in equilibrative nucleoside transporter 3 (ENT3), the only intracellular nucleoside transporter within the solute carrier 29 (SLC29) gene family, cause an expanding spectrum of human genetic disorders (e.g., H syndrome, PHID syndrome, and SHML/RDD syndrome). Here, we identify adult stem cell deficits that drive ENT3-related abnormalities in mice. ENT3 deficiency alters hematopoietic and mesenchymal stem cell fates; the former leads to stem cell exhaustion, and the latter leads to breaches of mesodermal tissue integrity. The molecular pathogenesis stems from the loss of lysosomal adenosine transport, which impedes autophagy-regulated stem cell differentiation programs via misregulation of the AMPK-mTOR-ULK axis. Furthermore, mass spectrometry-based metabolomics and bioenergetics studies identify defects in fatty acid utilization, and alterations in mitochondrial bioenergetics can additionally propel stem cell deficits. Genetic, pharmacologic and stem cell interventions ameliorate ENT3-disease pathologies and extend the lifespan of ENT3-deficient mice. These findings delineate a primary pathogenic basis for the development of ENT3 spectrum disorders and offer critical mechanistic insights into treating human ENT3-related disorders.


Assuntos
Células-Tronco Adultas/metabolismo , Proteínas de Transporte de Nucleosídeos/metabolismo , Adenosina/metabolismo , Adenilato Quinase/metabolismo , Células-Tronco Adultas/ultraestrutura , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacologia , Animais , Autofagia , Transporte Biológico , Diferenciação Celular , Autorrenovação Celular , Metabolismo Energético , Ácidos Graxos/metabolismo , Células HEK293 , Humanos , Metabolismo dos Lipídeos , Lisossomos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Biológicos , Fenótipo , Ribonucleotídeos/farmacologia , Transdução de Sinais , Análise de Sobrevida , Serina-Treonina Quinases TOR/metabolismo
12.
J Agric Food Chem ; 67(32): 8884-8895, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31345029

RESUMO

Leucine is an essential amino acid in the milk production of bovine mammary glands, but the regulatory roles and molecular mechanisms of leucine are still not known well. This study investigated the roles of leucine on milk synthesis and explored the corresponding mechanism in bovine mammary epithelial cells (BMECs). Leucine (0, 0.25, 0.5, 0.75, 1.0, and 1.25 mM) was added to BMECs that were cultured in FBS-free OPTI-MEM medium. Leucine significantly promoted milk protein and milk fat synthesis and also increased phosphorylation of mTOR signaling protein and the protein expression levels of SREBP-1c, with the most significant effects at 0.75 mM concentration. Leucine increased the expression and nuclear localization of DDX59, and loss and gain of gene function experiments further reveal that DDX59 mediates the stimulation of leucine on the mRNA expression variation of mTOR and SREBP-1c genes. PI3K inhibition experiment further detected that leucine upregulated expression of DDX59 and its downstream signaling via PI3K activation. ChIP-qPCR analysis further proved the binding of DDX59 to the promoter regions of mTOR and SREBP-1c. In summary, these data prove that DDX59 positively regulates the mTOR and SREBP-1c signaling pathways leading to synthesis of milk, and leucine regulates these two signaling pathways through the PI3K-DDX59 signaling.


Assuntos
Bovinos/metabolismo , Células Epiteliais/metabolismo , Leucina/metabolismo , Glândulas Mamárias Animais/metabolismo , Leite/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , RNA Helicases/metabolismo , Animais , Bovinos/genética , Feminino , Fosfatidilinositol 3-Quinases/genética , RNA Helicases/genética , Transdução de Sinais , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
13.
Gene ; 715: 144017, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31357026

RESUMO

SRY-related high-mobility-group box 9 (SOX9) is a member of the SOX family of transcription factors. Accumulating evidence has shown that SOX9 plays a significant role in various malignancies. However, the role of SOX9 in nasopharyngeal carcinoma (NPC) remains unknown. In the present study, up-regulation of SOX9 was observed in both NPC tissues and different NPC cells. Overexpression of SOX9 promoted NPC cell proliferation, migration and invasion. Conversely, knock down of SOX9 inhibited NPC proliferation, colony formation, migration and invasion. Mechanistically, SOX9 bound directly to the promoter region of BMP2 and increased BMP2 expression. In addition, overexpression of SOX9 activated the mTOR pathway partly through BMP2. Collectively, these results identify a novel role for SOX9 as a potential therapeutic marker for the prevention and treatment of NPC.


Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Movimento Celular , Proliferação de Células , Carcinoma Nasofaríngeo/metabolismo , Neoplasias Nasofaríngeas/metabolismo , Proteínas de Neoplasias/metabolismo , Fatores de Transcrição SOX9/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Proteína Morfogenética Óssea 2/genética , Linhagem Celular Tumoral , Humanos , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patologia , Invasividade Neoplásica , Proteínas de Neoplasias/genética , Fatores de Transcrição SOX9/genética , Serina-Treonina Quinases TOR/genética
14.
BMC Plant Biol ; 19(1): 258, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31208344

RESUMO

BACKGROUND: It has been previously shown that oligo-carrageenan (OC) kappa increases growth, photosynthesis and activities of enzymes involved in basal and secondary metabolisms in Eucalyptus globulus. However, it is not known whether OC kappa may induce the activation of TOR pathway and the increase in expression of genes encoding proteins involved in photosynthesis and enzymes of basal and secondary metabolisms. RESULTS: E. globulus trees were sprayed on leaves with water (control) or with OC kappa 1 mg mL- 1, once a week, four times in total, and cultivated for 17 additional weeks (21 weeks in total). Treated trees showed a higher level of net photosynthesis than controls, beginning at week 3, a higher height, beginning at week 9, and those differences remained until week 21. In addition, treated trees showed an increase in the level of glucose beginning at week 1, trehalose at weeks 1-3, and in TOR-P level at week 1-2. On the other hand, transcripts encoding proteins involved in photosynthesis, and enzymes involved in glucose accumulation, C, N and S assimilation, and synthesis of secondary metabolites began at weeks 3-4 and with additional peaks at weeks 5-6, 8-11,13-14 and 17-19. Thus, OC kappa induced initial increases in glucose, trehalose and TOR-P levels that were followed by oscillatory increases in the level of transcripts coding for proteins involved in photosynthesis, and in basal and secondary metabolisms suggesting that initial increases in glucose, trehalose and TOR-P may trigger activation of gene expression. CONCLUSIONS: The stimulation of growth induced by OC kappa in E. globulus trees is due, at least in part, to activation of TOR pathway and the increase in expression of genes encoding proteins involved in photosynthesis and enzymes of basal metabolism.


Assuntos
Carragenina/farmacologia , Fotossíntese/efeitos dos fármacos , Metabolismo Basal/genética , Eucalyptus/genética , Eucalyptus/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glucose/metabolismo , Fotossíntese/genética , Proteínas de Plantas/metabolismo , Metabolismo Secundário/efeitos dos fármacos , Metabolismo Secundário/genética , Serina-Treonina Quinases TOR/metabolismo , Trealose/metabolismo
15.
Biomed Environ Sci ; 32(5): 345-356, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31217051

RESUMO

OBJECTIVE: To investigate the molecular mechanisms of the adverse effects of exposure to sulfamonomethoxin (SMM) in pregnancy on the neurobehavioral development of male offspring. METHODS: Pregnant mice were randomly divided into four groups: control- (normal saline), low- [10 mg/(kg•day)], middle- [50 mg/(kg•day)], and high-dose [200 mg/(kg•day)] groups, which received SMM by gavage daily during gestational days 1-18. We measured the levels of short-chain fatty acids (SCFAs) in feces from dams and male pups. Furthermore, we analyzed the mRNA and protein levels of genes involved in the mammalian target of rapamycin (mTOR) pathway in the hippocampus of male pups by RT-PCR or Western blotting. RESULTS: Fecal SCFA concentrations were significantly decreased in dams. Moreover, the production of individual fecal SCFAs was unbalanced, with a tendency for an increased level of total fecal SCFAs in male pups on postnatal day (PND) 22 and 56. Furthermore, the phosphatidylinositol 3-kinase (PI3k)/protein kinase B (AKT)/mTOR or mTOR/ribosomal protein S6 kinase 1 (S6K1)/4EBP1 signaling pathway was continuously upregulated until PND 56 in male offspring. In addition, the expression of Sepiapterin Reductase (SPR), a potential target of mTOR, was inhibited. CONCLUSION: In utero exposure to SMM, persistent upregulation of the hippocampal mTOR pathway related to dysfunction of the gut (SCFA)-brain axis may contribute to cognitive deficits in male offspring.


Assuntos
Anti-Infecciosos/toxicidade , Hipocampo/efeitos dos fármacos , Memória/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Sulfamonometoxina/toxicidade , Oxirredutases do Álcool/metabolismo , Animais , Ácidos Graxos Voláteis/análise , Fezes/química , Feminino , Hipocampo/metabolismo , Masculino , Camundongos Endogâmicos ICR , Gravidez , Serina-Treonina Quinases TOR/metabolismo
16.
J Agric Food Chem ; 67(28): 7832-7843, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31242723

RESUMO

Oxidative-stress-induced senescence constitutes a great risk factor for chronic diseases. Therefore, ameliorating oxidative-stress-induced senescence is expected to prevent chronic diseases. The beneficial effects of bilberry anthocyanin (BA) on healthy aging were evaluated using 12 month old, aging female SD rats in this study. The experimental results suggested that consumption of a middle-dose of BA (MBA) appreciably increased the relative liver mass by 7.34% when compared with that of the AC group. Furthermore, BA significantly increased the total antioxidant capacity, total superoxide dismutase activity, and catalase activities; decreased malondialdehyde, serum low-density lipoprotein cholesterol (LDL-C), serum total cholesterol (TC), serum triglyceride (TG), and glycated serum protein (GSP) levels; and reduced TC/high-density lipoprotein cholesterol (HDL-C) and LDL-C/HDL-C ratios. In addition, MBA decreased the activity of fecal bacterial enzymes and increased the content of fecal short-chain fatty acids. The Western blot results showed that MBA significantly upregulated the expression of OCLN, ZO-1, and autophagy-related proteins (ATP6 V0C, ATG4D, and CTSB) in aging rats. Moreover, it also showed that MBA induced the phosphorylation of AMPK and FOXO3a and inhibited the phosphorylation of mTOR, which indicated that bilberry anthocyanin induced autophagy via the AMPK-mTOR signaling pathways. This induction of autophagy further promoted oxidative stress resistance effects and intestinal epithelial barrier function of bilberry anthocyanin in aging female rats.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Envelhecimento/fisiologia , Antocianinas/administração & dosagem , Autofagia/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Vaccinium myrtillus/química , Proteínas Quinases Ativadas por AMP/genética , Envelhecimento/sangue , Envelhecimento/efeitos dos fármacos , Envelhecimento/genética , Animais , Suplementos Nutricionais/análise , Feminino , Proteína Forkhead Box O3/genética , Proteína Forkhead Box O3/metabolismo , Humanos , Lipoproteínas LDL/sangue , Malondialdeído/sangue , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/genética , Triglicerídeos/sangue
17.
Eur J Med Chem ; 178: 667-686, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31228810

RESUMO

PI3K/Akt/mTOR signaling pathway plays an important role in cancer cell growth and survival. In this study, a new class of molecules with skeleton of 4-phenyl-2H-benzo[b] [1,4]oxazin-3(4H)-one were designed and synthesized targeting this pathway. Bioassays showed that, among all the molecules, 8d-1 was a pan-class I PI3K/mTOR inhibitor with an IC50 of 0.63 nM against PI3Kα. In a wide panel of protein kinases assays, no off-target interactions of 8d-1 were identified. 8d-1 was orally available, and displayed favorable pharmacokinetic parameters in mice (oral bioavailability of 24.1%). In addition, 8d-1 demonstrated significant efficiency in Hela/A549 tumor xenograft models (TGI of 87.7% at dose of 50 mg/kg in Hela model) without causing significant weight loss and toxicity during 30 days treatment. Based on the bioassays, compound 8d-1 could be used as an anti-cancer drug candidate.


Assuntos
Antineoplásicos/farmacologia , Benzoxazinas/farmacologia , Descoberta de Drogas , Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Administração Oral , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Benzoxazinas/administração & dosagem , Benzoxazinas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/química , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Serina-Treonina Quinases TOR/metabolismo
18.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(4): 344-350; 356, 2019 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-31167694

RESUMO

Objective To investigate the mechanism of serine hydroxymethyl transferase 2 (SHMT2) inducing autophagy and promoting chemotherapy resistance in colon cancer cells. Methods TCGA database and real-time quantitative PCR were used to analyze the level of SHMT2 mRNA in colon cancer tissues. Western blot analysis and immunohistochemistry were used to detect the expression and distribution of SHMT2 in colon cancer tissues. Western blot analysis was performed to detect the SHMT2 protein levels of SW480, SW620, HCT116, CACO2, RKO, HCT8, HT15 and HT29 cells. After over-expression of SHMT2 in CACO2 colon cancer cells, MTT assay was used to detect cell viability, and annexin V-FITC/PI double labeling was used to detect the apoptosis of colon cancer cells induced by 5-fluorouracil (5-Fu). The autophagosomes of colon cancer cells were observed by transmission electron microscopy. The protein levels of LC3 II/I, P62, cleaved PARP (c-PARP), and cleaved caspase-3 (c-caspase-3) were examined by Western blot analysis. Signaling Phospho-Antibody Array and Western blot analysis were applied to analyze the phosphorylation level of AMPK/mTOR. Results SHMT2 was highly expressed in colon cancer tissues and cells. Over-expression of SHMT2 significantly increased cell viability and the ratio of LC3 II/ LC3 I. It was found that the phosphorylation level of AMPK was raised and the phosphorylation level of mTOR was reduced after the over-expression of SHMT2. Conclusion SHMT2 may induce autophagy by promoting AMPK phosphorylation and directly or indirectly inhibiting mTOR activity, thus leading to chemotherapy-induced apoptosis tolerance and resistance to chemotherapeutics.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia , Neoplasias do Colo/enzimologia , Resistencia a Medicamentos Antineoplásicos , Glicina Hidroximetiltransferase/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Apoptose , Células CACO-2 , Neoplasias do Colo/tratamento farmacológico , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Transdução de Sinais
19.
Expert Opin Investig Drugs ; 28(7): 583-592, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31215251

RESUMO

Introduction: PDAC is a lethal malignancy with a clear unmet need; almost all patients fail 1st, 2nd, and 3rd line multi-agent cytotoxic chemotherapy. The mammalian target of rapamycin (mTOR) has been identified as a key signaling node enhancing tumor survival and drug resistance in PDAC; hence, it is considered a promising therapeutic target. Areas covered: We comprehensively reviewed the evidence from preclinical and phase I and II clinical trials, based on the authors'clinical experience and a PubMed, Cochrane library, Embase, and Google Scholar search everolimus + pancreatic cancer. Expert opinion: Everolimus has not demonstrated efficacy in PDAC; however, an mTOR inhibitor in combination with stroma-targeted therapies may be a promising area to explore in clinical trials.


Assuntos
Carcinoma Ductal Pancreático/tratamento farmacológico , Everolimo/administração & dosagem , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Carcinoma Ductal Pancreático/patologia , Resistencia a Medicamentos Antineoplásicos , Everolimo/farmacologia , Humanos , Terapia de Alvo Molecular , Neoplasias Pancreáticas/patologia , Sobrevida , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo
20.
BMC Complement Altern Med ; 19(1): 122, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31182089

RESUMO

BACKGROUD: The regenerative capacity of the liver is crucial for the host to survive after serious hepatic injuries, tumor resection, or living donor liver transplantation. Panax notoginseng saponins (PNS) have been reported to exert protective effects during organ injuries. The present study aimed to evaluate the effect of PNS on liver regeneration(LR) and on injuries induced by partial hepatectomy (PH). METHODS: We performed 70% partial PH on C57BL/6 J mice treated with or without PNS. LR was estimated by liver weight/body weight, serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels and cell proliferation, and the related cellular signals were analyzed by Western blot. RESULTS: Different concentrations of PNS promoted hepatocyte proliferation in vitro. Mice in the PNS group showed higher liver/body weight ratios at 2 d and 7 d (P < 0.05) after PH and lower levels of serum ALT and AST (P < 0.05) compared to those of mice in the normal control (NC) group. Histological analysis showed that the expression of proliferating cell nuclear antigen(PCNA) at 2 d and 7 d after PH was significantly higher in the PNS group than in the NC group (P < 0.05). Mechanistically, the AKT/mTOR cell proliferation pathway and AKT/Bad cell survival pathway were activated by PNS, which accelerated hepatocyte proliferation and inhibited apoptosis (P < 0.05). CONCLUSIONS: PNS promoted liver regeneration through activation of PI3K/AKT/mTOR and upregulated the AKT/Bad cell pathways in mice.


Assuntos
Proliferação de Células/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Regeneração Hepática/efeitos dos fármacos , Panax notoginseng , Saponinas/farmacologia , Animais , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Masculino , Camundongos Endogâmicos C57BL , Fosfatidilinositol 3-Quinases/metabolismo , Fitoterapia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Proteína de Morte Celular Associada a bcl/metabolismo
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