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1.
Acta Pharmacol Sin ; 40(8): 1067-1075, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30670815

RESUMO

Triple-negative breast cancer (TNBC) is a heterogeneous disease with a poor prognosis due to the lack of an effective targeted therapy. Histone lysine methyltransferases (KMTs) have emerged as attractive drug targets for cancer therapy. However, the function of the majority of KMTs in TNBC has remained largely unknown. In the current study, we found that KMT nuclear receptor binding SET domain protein 2 (NSD2) is overexpressed in TNBC tumors and that its overexpression is associated with poor survival of TNBC patients. NSD2 regulates TNBC cell survival and invasion and is required for tumorigenesis and tumor growth. Mechanistically, NSD2 directly controls the expression of EGFR and ADAM9, a member of the ADAM (a disintegrin and metalloproteinase) family that mediates the release of growth factors, such as HB-EGF. Through its methylase activity, NSD2 overexpression stimulates EGFR-AKT signaling and promotes TNBC cell resistance to the EGFR inhibitor gefitinib. Together, our results identify NSD2 as a major epigenetic regulator in TNBC and provide a rationale for targeting NSD2 alone or in combination with EGFR inhibitors as a targeted therapy for TNBC.


Assuntos
Proteínas ADAM/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais/fisiologia , Neoplasias de Mama Triplo Negativas/fisiopatologia , Proteínas ADAM/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Receptores ErbB/genética , Receptores ErbB/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Técnicas de Silenciamento de Genes , Histona-Lisina N-Metiltransferase/genética , Humanos , Proteínas de Membrana/genética , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica/fisiopatologia , Proteínas Repressoras/genética , Neoplasias de Mama Triplo Negativas/patologia
2.
Acta Pharmacol Sin ; 40(5): 589-598, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30030529

RESUMO

High-mobility group box 1 (HMGB1) exhibits various functions according to its subcellular location, which is finely conditioned by diverse post-translational modifications, such as acetylation. The nuclear HMGB1 may prevent from cardiac hypertrophy, whereas its exogenous protein is proven to induce hypertrophic response. This present study sought to investigate the regulatory relationships between poly(ADP-ribose) polymerase 1 (PARP1) and HMGB1 in the process of pathological myocardial hypertrophy. Primary-cultured neonatal rat cardiomyocytes (NRCMs) were respectively incubated with three cardiac hypertrophic stimulants, including angiotensin II (Ang II), phenylephrine (PE), and isoproterenol (ISO), and cell surface area and the mRNA expression of hypertrophic biomarkers were measured. the catalytic activity of PARP1 was remarkably enhanced, meanwhile HMGB1 excluded from the nucleus. PARP1 overexpression by infecting with adenovirus PARP1 (Ad-PARP1) promoted the nuclear export of HMGB1, facilitated its secretion outside the cell, aggravated cardiomyocyte hypertrophy, which could be alleviated by HMGB1 overexpression. PE treatment led to the similar results, while that effect was widely depressed by PARP1 silencing or its specific inhibitor AG14361. Moreover, SD rats were intraperitoneally injected with 3-aminobenzamide (3AB, 20 mg/kg every day, a well-established PARP1 inhibitor) 7 days after abdominal aortic constriction (AAC) surgery for 6 weeks, echocardiography and morphometry of the hearts were measured. Pre-treatment of 3AB relieved AAC-caused the translocation of nuclear HMGB1 protein, cardiac hypertrophy, and heart dysfunction. Our research offers a novel evidence that PARP1 combines with HMGB1 and accelerates its translocation from nucleus to cytoplasm, and the course finally causes cardiac hypertrophy.


Assuntos
Cardiomegalia/etiologia , Núcleo Celular/metabolismo , Proteína HMGB1/metabolismo , Poli(ADP-Ribose) Polimerase-1/metabolismo , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Angiotensina II/farmacologia , Animais , Isoproterenol/farmacologia , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Fenilefrina/farmacologia , Ratos Sprague-Dawley
3.
Acta Pharmacol Sin ; 39(12): 1837-1846, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29991711

RESUMO

Vascular endothelial cell senescence is a leading cause of age-associated and vascular diseases. Mammalian target of rapamycin complex 2 (mTORC2) is a conserved serine/threonine (Ser/Thr) protein kinase that plays an important regulatory role in various cellular processes. However, its impact on endothelial senescence remains controversial. In this study we investigated the role and molecular mechanisms of mTORC2 in endothelial senescence. A replicative senescence model and H2O2-induced premature senescence model were established in primary cultured human umbilical vein endothelial cells (HUVECs). In these senescence models, the formation and activation of mTORC2 were significantly increased, evidenced by the increases in binding of Rictor (the essential component of mTORC2) to mTOR, phosphorylation of mTOR at Ser2481 and phosphorylation of Akt (the effector of mTORC2) at Ser473. Knockdown of Rictor or treatment with the Akt inhibitor MK-2206 attenuated senescence-associated ß-galactosidase (ß-gal) staining and expression of p53 and p21 proteins in the senescent endothelial cells, suggesting that mTORC2/Akt facilitates endothelial senescence. The effect of mTORC2/Akt on endothelial senescence was due to suppression of nuclear factor erythroid 2-related factor 2 (Nrf2) at the transcriptional level, since knockdown of Rictor reversed the reduction of Nrf2 mRNA expression in endothelial senescence. Furthermore, mTORC2 suppressed the expression of Nrf2 via the Akt/GSK-3ß/C/EBPα signaling pathway. These results suggest that the mTORC2/Akt/GSK-3ß/C/EBPα/Nrf2 signaling pathway is involved in both replicative and inducible endothelial senescence. The deleterious role of mTORC2 in endothelial cell senescence suggests therapeutic strategies (targeting mTORC2) for aging-associated diseases and vascular diseases.


Assuntos
Senescência Celular/fisiologia , Células Endoteliais/fisiologia , Alvo Mecanístico do Complexo 2 de Rapamicina/fisiologia , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/fisiologia
4.
Acta Pharmacol Sin ; 39(5): 802-824, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29698387

RESUMO

Salvia miltiorrhiza Burge (Danshen) is an eminent medicinal herb that possesses broad cardiovascular and cerebrovascular protective actions and has been used in Asian countries for many centuries. Accumulating evidence suggests that Danshen and its components prevent vascular diseases, in particular, atherosclerosis and cardiac diseases, including myocardial infarction, myocardial ischemia/reperfusion injury, arrhythmia, cardiac hypertrophy and cardiac fibrosis. The published literature indicates that lipophilic constituents (tanshinone I, tanshinone IIa, tanshinone IIb, cryptotanshinone, dihydrotanshinone, etc) as well as hydrophilic constituents (danshensu, salvianolic acid A and B, protocatechuic aldehyde, etc) contribute to the cardiovascular protective actions of Danshen, suggesting a potential synergism among these constituents. Herein, we provide a systematic up-to-date review on the cardiovascular actions and therapeutic potential of major pharmacologically active constituents of Danshen. These bioactive compounds will serve as excellent drug candidates in small-molecule cardiovascular drug discovery. This article also provides a scientific rationale for understanding the traditional use of Danshen in cardiovascular therapeutics.


Assuntos
Cardiotônicos/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Animais , Doenças Cardiovasculares/fisiopatologia , Sinergismo Farmacológico , Células Endoteliais/efeitos dos fármacos , Fibrinolíticos/uso terapêutico , Humanos , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Salvia miltiorrhiza
5.
Acta Pharmacol Sin ; 39(8): 1294-1304, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29323338

RESUMO

Ulinastatin (UTI) is a broad-spectrum serine protease inhibitor isolated and purified from human urine with strong anti-inflammatory and cytoprotective actions, which is widely used for the treatment of various diseases, such as pancreatitis and sepsis. Although the therapeutic effects of UTI are reported to be associated with a variety of mechanisms, the signaling pathways mediating the anti-inflammatory action of UTI remain to be elucidated. In the present study we carried out a systematic study on the anti-inflammatory and anti-oxidative mechanisms of UTI and their relationships in LPS-treated RAW264.7 cells. Pretreatment with UTI (1000 and 5000 U/mL) dose-dependently decreased the mRNA levels of pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α, iNOS) and upregulated anti-inflammatory cytokines (IL-10 and TGF-ß1) in LPS-treated RAW264.7 cells. UTI pretreatment significantly inhibited the nuclear translocation of NF-κB by preventing the degradation of IκB-α. UTI pretreatment only markedly inhibited the phosphorylation of JNK at Thr183, but it did not affect the phosphorylation of JNK at Tyr185, ERK-1/2 and p38 MAPK; JNK was found to function upstream of the IκB-α/NF-κB signaling pathway. Furthermore, UTI pretreatment significantly suppressed LPS-induced ROS production by activating PI3K/Akt pathways and the nuclear translocation of Nrf2 via promotion of p62-associated Keap1 degradation. However, JNK was not involved in mediating the anti-oxidative stress effects of UTI. In summary, this study shows that UTI exerts both anti-inflammatory and anti-oxidative effects by targeting the JNK/NF-κB and PI3K/Akt/Nrf2 pathways.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Glicoproteínas/farmacologia , Inflamação/tratamento farmacológico , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Inibidores de Serino Proteinase/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Citocinas/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Inibidor de NF-kappaB alfa/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células RAW 264.7 , Fator de Transcrição RelA/metabolismo
6.
Acta Pharmacol Sin ; 39(2): 184-194, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28816235

RESUMO

The RasGAP SH3 domain-binding proteins (G3BPs) are a family of RNA-binding proteins that can co-ordinate signal transduction and post-transcriptional gene regulation. G3BPs have been shown to be involved in mediating a great diversity of cellular processes such as cell survival, growth, proliferation and apoptosis. But the potential roles of G3BPs in the pathogenesis and progression of cardiovascular diseases remain to be clarified. In the present study, we provide the first evidence that suggests the participation of G3BP2 in cardiac hypertrophy. In cultured neonatal rat cardiomyocytes (NRCMs), treatment with isoproterenol (ISO, 0.1-100 µmol/L) significantly elevated the mRNA and protein levels of G3BP2. Similar results were observed in the hearts of rats subjected to 7D-injection of ISO, accompanied by obvious heart hypertrophy and elevated the expression of hypertrophy marker genes ANF, BNP and ß-MHC in heart tissues. Overexpression of G3BP2 in NRCMs led to hypertrophic responses evidenced by increased cellular surface area and the expression of hypertrophy marker genes, whereas knockdown of G3BP2 significantly attenuated ISO-induced hypertrophy of NRCMs. We further showed that G3BP2 directly interacted with IκBα and promoted the aggregation of the NF-κB subunit p65 in the nucleus and increased NF-κB-dependent transcriptional activity. NF-κB inhibition with PDTC (50 µmol/L) or p65 knockdown significantly decreased the hypertrophic responses in NRCMs induced by ISO or G3BP2 overexpression. These results give new insight into the functions of G3BP2 and may help further elucidate the molecular mechanisms underlying cardiac hypertrophy.


Assuntos
Cardiomegalia/metabolismo , Reguladores de Proteínas de Ligação ao GTP/metabolismo , Miócitos Cardíacos/metabolismo , NF-kappa B/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Cardiomegalia/induzido quimicamente , Cardiomegalia/patologia , Núcleo Celular/metabolismo , Modelos Animais de Doenças , Reguladores de Proteínas de Ligação ao GTP/genética , Técnicas de Silenciamento de Genes , Isoproterenol , Masculino , Miócitos Cardíacos/patologia , Inibidor de NF-kappaB alfa/metabolismo , NF-kappa B/antagonistas & inibidores , Pirrolidinas/farmacologia , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Tiocarbamatos/farmacologia , Fator de Transcrição RelA/metabolismo
7.
Acta Pharmacol Sin ; 38(9): 1257-1268, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28649129

RESUMO

Phosphodiesterase-9A (PDE9A) expression is upregulated during cardiac hypertrophy and heart failure. Accumulating evidence suggests that PDE9A might be a promising therapeutic target for heart diseases. The present study sought to investigate the effects and underlying mechanisms of C33(S), a novel selective PDE9A inhibitor, on cardiac hypertrophy in vitro and in vivo. Treatment of neonatal rat cardiomyocytes (NRCMs) with PE (100 µmol/L) or ISO (1 µmol/L) induced cardiac hypertrophy characterized by significantly increased cell surface areas and increased expression of fetal genes (ANF and BNP). Furthermore, PE or ISO significantly increased the expression of PDE9A in the cells; whereas knockdown of PDE9A significantly alleviated PE-induced hypertrophic responses. Moreover, pretreatment with PDE9A inhibitor C33(S) (50 and 500 nmol/L) or PF-7943 (2 µmol/L) also alleviated the cardiac hypertrophic responses in PE-treated NRCMs. Abdominal aortic constriction (AAC)-induced cardiac hypertrophy and ISO-induced heart failure were established in SD rats. In ISO-treated rats, oral administration of C33(S) (9, 3, and 1 mg·kg-1·d-1, for 3 consecutive weeks) significantly increased fractional shortening (43.55%±3.98%, 54.79%±1.95%, 43.98%±7.96% vs 32.18%±6.28%), ejection fraction (72.97%±4.64%, 84.29%±1.56%, 73.41%±9.37% vs 49.17%±4.20%) and cardiac output (60.01±9.11, 69.40±11.63, 58.08±8.47 mL/min vs 48.97±2.11 mL/min) but decreased the left ventricular internal diameter, suggesting that the transition to heart failure was postponed by C33(S). We further revealed that C33(S) significantly elevated intracellular cGMP levels, phosphorylation of phospholamban (PLB) and expression of SERCA2a in PE-treated NRCMs in vitro and in ISO-induced heart failure model in vivo. Our results demonstrate that C33(S) effectively protects against cardiac hypertrophy and postpones the transition to heart failure, suggesting that it is a promising agent in the treatment of cardiac diseases.


Assuntos
3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Cardiomegalia/tratamento farmacológico , GMP Cíclico/metabolismo , Inibidores Enzimáticos/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , 3',5'-AMP Cíclico Fosfodiesterases/metabolismo , Animais , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Células Cultivadas , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Pirazóis/administração & dosagem , Pirazóis/química , Pirimidinas/administração & dosagem , Pirimidinas/química , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
8.
Acta Pharmacol Sin ; 38(5): 638-650, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28239158

RESUMO

We previously identified AG-690/11026014 (6014) as a novel poly(ADP-ribose) polymerase-1 (PARP-1) inhibitor that effectively prevented angiotensin II (Ang II)-induced cardiomyocyte hypertrophy. In the present study, we reported a new synthesis route for 6014, and investigated its protective effects on Ang II-induced cardiac remodeling and cardiac dysfunction and the underlying mechanisms in mice. We designed a new synthesis route to obtain a sufficient quantity of 6014 for this in vivo study. C57BL/6J mice were infused with Ang II and treated with 6014 (10, 30, 90 mg·kg-1·d-1, ig) for 4 weeks. Then two-dimensional echocardiography was performed to assess the cardiac function and structure. Histological changes of the hearts were examined with HE staining and Masson's trichrome staining. The protein expression was evaluated by Western blot, immunohistochemistry and immunofluorescence assays. The activities of sirtuin-1 (SIRT-1) and the content of NAD+ were detected with the corresponding test kits. Treatment with 6014 dose-dependently improved cardiac function, including LVEF, CO and SV and reversed the changes of cardiac structure in Ang II-infused mice: it significantly ameliorated Ang II-induced cardiac hypertrophy evidenced by attenuating the enlargement of cardiomyocytes, decreased HW/BW and LVW/BW, and decreased expression of hypertrophic markers ANF, BNP and ß-MHC; it also prevented Ang II-induced cardiac fibrosis, as implied by the decrease in excess accumulation of extracellular matrix (ECM) components collagen I, collagen III and FN. Further studies revealed that treatment with 6014 did not affect the expression levels of PARP-1, but dose-dependently inhibited the activity of PARP-1 and subsequently restored the activity of SIRT-1 in heart tissues due to the decreased consumption of NAD+ and attenuated Poly-ADP-ribosylation (PARylation) of SIRT-1. In conclusion, the novel PARP-1 inhibitor 6014 effectively protects mice against AngII-induced cardiac remodeling and improves cardiac function. Thus, 6014 might be a potential therapeutic agent for heart diseases..


Assuntos
Cardiomegalia/terapia , Cardiotônicos/uso terapêutico , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Tioglicolatos/uso terapêutico , Remodelação Ventricular/efeitos dos fármacos , Xantinas/uso terapêutico , Angiotensina II/farmacologia , Animais , Cardiomegalia/induzido quimicamente , Cardiotônicos/síntese química , Fibrose/induzido quimicamente , Fibrose/terapia , Masculino , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Sirtuína 1/metabolismo , Tioglicolatos/síntese química , Xantinas/síntese química
9.
Transl Res ; 180: 91-102.e1, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27639592

RESUMO

Heart failure (HF) is associated with myocardial energy metabolic abnormality. Receptor-interacting protein 140 (RIP140) is an important transcriptional cofactor for maintaining energy balance in high-oxygen consumption tissues. However, the role of RIP140 in the pathologic processes of HF remains to be elucidated. In this study, we investigated the role of RIP140 in mitochondrial and cardiac functions in rodent hearts under myocardial infarction (MI) stress. MI was created by a permanent ligation of left anterior descending coronary artery and exogenous expression of RIP140 by adenovirus (Ad) vector delivery. Four weeks after MI or Ad-RIP140 treatment, cardiac function was assessed by echocardiographic and hemodynamics analyses, and the mitochondrial function was determined by mitochondrial genes expression, biogenesis, and respiration rates. In Ad-RIP140 or MI group, a subset of metabolic genes changed, accompanied with slight reductions in mitochondrial biogenesis and respiration rates but no change in adenosine triphosphate (ATP) content. Cardiac malfunction was compensated. However, under MI stress, rats overexpressing RIP140 exhibited greater repressions in mitochondrial genes, state 3 respiration rates, respiration control ratio, and ATP content and had further deteriorated cardiac malfunction. In conclusion, RIP140 overexpression leads to comparable cardiac function as resulted from MI, but RIP140 aggravates metabolic repression, mitochondrial malfunction, and further accelerates the transition to HF in response to MI stress.


Assuntos
Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/metabolismo , Mitocôndrias Cardíacas/metabolismo , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Correpressor 1 de Receptor Nuclear/metabolismo , Trifosfato de Adenosina/metabolismo , Adenoviridae/metabolismo , Animais , Respiração Celular , Doença Crônica , Eletrocardiografia , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Vetores Genéticos/metabolismo , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica , Masculino , Mitocôndrias Cardíacas/ultraestrutura , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Miocárdio/patologia , Miocárdio/ultraestrutura , Biogênese de Organelas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Disfunção Ventricular Esquerda
10.
Mol Neurobiol ; 54(3): 2209-2222, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-26941101

RESUMO

Methylene blue (MB) can ameliorate behavioral, neurochemical, and neuropathological impairments in animal models of acute and chronic neurodegenerative disorders, but the underlying mechanism remains unclear. Myocyte enhancer factor 2 (MEF2D) is known to promote neuronal survival in several models, and several survival and death signals converge on MEF2D and regulate its activity. Here, we investigated the role of MEF2D in the neuroprotective effect of MB against glutamate-induced toxicity in HT22 neuronal cells. Our results showed that MB, event at less than 100 nM, improved the viability of HT22 cells exposed to 2 mM glutamate. MB attenuated the mitochondrial impairment and quenches the reactive oxygen species (ROS) induced by glutamate. Surprisingly, MB at 50-200 nM did not affect the Nrf2/HO-1 pathway, an important endogenous anti-oxidative system. Further study showed that MB increased the transcription and translation of MEF2D. In addition, MB upregulated the expression of mitochondrial NADH dehydrogenase 6 (ND6) in a MEF2D-dependent manner. Knockdown of MEF2D abolished both MB-medicated increase of ND6 and MB-induced neuroprotection against glutamate-induced toxicity. Moreover, we showed that MB promoted Akt function activity, suppressed GSK-3ß activity, and increased MEF2D level in hippocampus of mice and HT22 cells. These findings for the first time demonstrate that MB protects HT22 neuronal cells against glutamate-induced cell death partially via the regulation of MEF2D-associated survival pathway.


Assuntos
Hipocampo/efeitos dos fármacos , Azul de Metileno/farmacologia , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Ácido Glutâmico/farmacologia , Hipocampo/metabolismo , Fatores de Transcrição MEF2/metabolismo , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
Transl Res ; 166(5): 459-473.e3, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26118953

RESUMO

Peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) is a crucial coregulator interacting with multiple transcriptional factors in the regulation of cardiac hypertrophy. The present study revealed that PGC-1α protected cardiomyocytes from hypertrophy by suppressing calcineurin-nuclear factor of activated T cells c4 (NFATc4) signaling pathway. Overexpression of PGC-1α by adenovirus infection prevented the increased protein and messenger RNA expression of NFATc4 in phenylephrine (PE)-treated hypertrophic cardiomyocytes, whereas knockdown of PGC-1α by RNA silencing augmented the expression of NFATc4. An interaction between PGC-1α and NFATc4 was observed in both the cytoplasm and nucleus of neonatal rat cardiomyocytes. Adenovirus PGC-1α prevented the nuclear import of NFATc4 and increased its phosphorylation level of NFATc4, probably through repressing the expression and activity of calcineurin and interfering with the interaction between calcineurin and NFATc4. On the contrary, PGC-1α silencing aggravated PE-induced calcineurin activation, NFATc4 dephosphorylation, and nuclear translocation. Moreover, the binding activity and transcription activity of NFATc4 to DNA promoter of brain natriuretic peptide were abrogated by PGC-1α overexpression but were enhanced by PGC-1α knockdown. The effect of PGC-1α on suppressing the calcinuerin-NFATc4 signaling pathway might at least partially contribute to the protective effect of PGC-1α on cardiomyocyte hypertrophy. These findings provide novel insights into the role of PGC-1α in regulation of cardiac hypertrophy.


Assuntos
Cardiomegalia/prevenção & controle , Miócitos Cardíacos/metabolismo , Fatores de Transcrição NFATC/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Transdução de Sinais , Fatores de Transcrição/fisiologia , Animais , Cardiomegalia/metabolismo , Masculino , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Ratos , Ratos Sprague-Dawley
13.
Br J Pharmacol ; 172(11): 2852-63, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25625556

RESUMO

BACKGROUND AND PURPOSE: The orphan nuclear receptor NOR1 belongs to the NR4A subfamily of the nuclear hormone receptor superfamily, and is involved in glucose and fat metabolism. However, its potential contribution to cardiovascular diseases remains to be assessed. Here, the roles of NOR1 in cardiac hypertrophy induced by isoprenaline and the underlying molecular mechanisms were investigated. EXPERIMENTAL APPROACH: NOR1 was expressed in cardiomyocytes treated with isoprenaline. After NOR1 overexpression or knockdown in neonatal rat cardiomyocytes, cellular hypertrophy was monitored by measuring cell surface area and the mRNA of hypertrophic biomarkers. Interactions between NOR1 and PARP-1 were investigated by co-immunoprecipitation. NOR1 expression and PARP-1 activity were measured in rats with cardiac hypertrophy induced by isoprenaline. KEY RESULTS: Treatment with isoprenaline significantly up-regulated NOR1 expression and PARP-1 activity both in vivo and in vitro. Specific gene silencing of NOR1 attenuated isoprenaline-induced cardiomyocyte hypertrophy, whereas NOR1 overexpression exacerbated cardiac hypertrophy. We identified a physical interaction between NOR1 and PARP-1, which was enhanced by NOR1 transfection and thereby led to PARP-1 activation. Overexpression of NOR1, but not C293Y, a NOR1 mutant lacking the PARP-1 binding activity, increased cellular surface area and the mRNA levels of atrial natriuretic factor and brain natriuretic polypeptide, effects blocked by the PARP-1 inhibitor 3-aminobenzamide or siRNA for PARP-1. CONCLUSIONS AND IMPLICATIONS: This is the first evidence that NOR1 was involved in isoprenaline-induced cardiac hypertrophy. The pro-hypertrophic effect of NOR1 can be partly attributed to its regulation of PARP-1 enzymic activity.


Assuntos
Cardiomegalia/genética , Proteínas de Ligação a DNA/efeitos dos fármacos , Isoproterenol/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Proteínas do Tecido Nervoso/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/efeitos dos fármacos , RNA Mensageiro/efeitos dos fármacos , Simpatomiméticos/farmacologia , Animais , Fator Natriurético Atrial/efeitos dos fármacos , Fator Natriurético Atrial/genética , Fator Natriurético Atrial/metabolismo , Cardiomegalia/induzido quimicamente , Cardiomegalia/metabolismo , Células Cultivadas , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Técnicas de Introdução de Genes , Técnicas de Silenciamento de Genes , Imunoprecipitação , Técnicas In Vitro , Isoproterenol/toxicidade , Miócitos Cardíacos/metabolismo , Peptídeo Natriurético Encefálico/efeitos dos fármacos , Peptídeo Natriurético Encefálico/genética , Peptídeo Natriurético Encefálico/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Poli(ADP-Ribose) Polimerase-1 , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , RNA Mensageiro/metabolismo , Ratos , Simpatomiméticos/toxicidade , Regulação para Cima
14.
Hepatology ; 61(4): 1284-94, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25503676

RESUMO

UNLABELLED: The deregulation of microRNAs (miRNAs) plays an important role in human hepatocarcinogenesis. In this study, we highlight exosomes as mediators involved in modulating miRNA profiles in hepatocellular carcinoma (HCC) cells. First, we examined the different miRNA expression profiles in HCC cells and HCC cell-derived exosomes. Next, coculture experiments indicated that HCC cell-derived exosomes promoted the cell growth, migration, and invasion of HCC cells and had the ability to shuttle miRNAs to recipient cells. Further, our data showed that Vps4A, a key regulator of exosome biogenesis, was frequently down-regulated in HCC tissues. The reduction of Vps4A in HCC tissues was associated with tumor progression and metastasis. In vitro studies revealed that Vps4A repressed the growth, colony formation, migration, and invasion of HCC cells. We further investigated the role and involvement of Vps4A in suppressing the bioactivity of exosomes and characterized its ability to weaken the cell response to exosomes. By small RNA sequencing, we demonstrated that Vps4A facilitated the secretion of oncogenic miRNAs in exosomes as well as accumulation and uptake of tumor suppressor miRNAs in cells. A subset of Vps4A-associated miRNAs was identified. Kyoto Encyclopedia of Genes and Genomes pathway analysis indicated that the phosphatidylinositol-3-kinase/Akt signaling pathway was the most likely candidate pathway for modulation by these miRNAs. Indeed, we proved that the phosphatidylinositol-3-kinase/Akt pathway was inactivated by Vps4A overexpression. CONCLUSION: Exosome-mediated miRNA transfer is an important mechanism of self-modulation of the miRNA expression profiles in HCC cells, and Vps4A may function as a tumor suppressor, which utilizes exosomes as mediators to regulate the secretion and uptake of miRNAs in hepatoma cells; these observations provide new insights into the development of HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/fisiologia , Exossomos/metabolismo , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , Proteínas Supressoras de Tumor/fisiologia , ATPases Vacuolares Próton-Translocadoras/fisiologia , ATPases Associadas a Diversas Atividades Celulares , Genes Supressores de Tumor , Humanos , Células Tumorais Cultivadas
15.
Arch Biochem Biophys ; 565: 76-88, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25436917

RESUMO

Adipose triglyceride lipase (ATGL), the rate-limiting enzyme of triglyceride (TG) hydrolysis, plays an important role in TG metabolism. ATGL knockout mice suffer from TG accumulation and die from heart failure. However, the mechanisms underlying cardiac hypertrophy caused by ATGL dysfunction remain unknown. In this study, we found that ATGL expression declined in pressure overload-induced cardiac hypertrophy in vivo and phenylephrine (PE)-induced cardiomyocyte hypertrophy in vitro. ATGL knockdown led to cardiomyocyte hypertrophy, while ATGL overexpression prevented PE-induced hypertrophy. In addition, ATGL downregulation increased but ATGL overexpression reduced the contents of ceramide, which has been proved to be closely associated with cardiac hypertrophy. Moreover, the accumulation of ceramide was due to elevation of free fatty acids in ATGL-knockdown cardiomyocytes, which could be explained by the reduced activity of peroxisome proliferator-activated receptor (PPAR) α leading to imbalance of fatty acid uptake and oxidation. These observations suggest that downregulation of ATGL causes the decreased PPARα activity which results in the imbalance of FA uptake and oxidation, elevating intracellular FFA contents to promote the accumulation of ceramides, and finally inducing cardiac hypertrophy. Upregulation of ATGL could be a strategy for ameliorating lipotoxic damage in cardiac hypertrophy.


Assuntos
Cardiomegalia/enzimologia , Ceramidas/metabolismo , Regulação Enzimológica da Expressão Gênica , Lipase/biossíntese , Miócitos Cardíacos/enzimologia , Animais , Cardiomegalia/genética , Cardiomegalia/patologia , Ceramidas/genética , Técnicas de Silenciamento de Genes , Lipase/genética , Masculino , Camundongos , Miócitos Cardíacos/patologia , Oxirredução , PPAR alfa/genética , PPAR alfa/metabolismo , Ratos , Ratos Sprague-Dawley
16.
J Mol Cell Cardiol ; 79: 92-103, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25446184

RESUMO

BACKGROUND: α-Enolase is a glycolytic enzyme with "second jobs" beyond its catalytic activity. However, its possible contribution to cardiac dysfunction remains to be determined. The present study aimed to investigate the role of α-enolase in doxorubicin (Dox)-induced cardiomyopathy as well as the underlying mechanisms. EXPERIMENTAL APPROACHES: The expression of α-enolase was detected in rat hearts and primary cultured rat cardiomyocytes with or without Dox administration. An adenovirus carrying short-hairpin interfering RNA targeting α-enolase was constructed and transduced specifically into the heart by intramyocardial injection. Heart function, cell apoptosis and mitochondrial function were measured following Dox administration. In addition, by using gain- and loss-of-function approaches to regulate α-enolase expression in primary cultured rat cardiomyocytes, we investigated the role of endogenous, wide type and catalytically inactive mutant α-enolase in cardiomyocyte apoptosis and ATP generation. Furthermore, the involvement of α-enolase in AMPK phosphorylation was also studied. KEY RESULTS: The mRNA and protein expression of cardiac α-enolase was significantly upregulated by Dox. Genetic silencing of α-enolase in rat hearts and cultured cardiomyocytes attenuated Dox-induced apoptosis and mitochondrial dysfunction. In contrast, overexpression of wide-type or catalytically inactive α-enolase in cardiomyocytes mimicked the detrimental role of Dox in inducing apoptosis and ATP reduction. AMPK dephosphorylation was further demonstrated to be involved in the proapoptotic and ATP-depriving effects of α-enolase. CONCLUSION: Our findings provided the evidence that α-enolase has a catalytically independent role in inducing cardiomyocyte apoptosis and mitochondrial dysfunction, which could be at least partially contributed to the inhibition of AMPK phosphorylation.


Assuntos
Apoptose/efeitos dos fármacos , Doxorrubicina/farmacologia , Mitocôndrias/metabolismo , Miócitos Cardíacos/enzimologia , Fosfopiruvato Hidratase/metabolismo , Trifosfato de Adenosina/metabolismo , Adenoviridae/metabolismo , Adenilato Quinase/metabolismo , Animais , Biocatálise/efeitos dos fármacos , Respiração Celular/efeitos dos fármacos , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Miocárdio/enzimologia , Miócitos Cardíacos/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Ratos Sprague-Dawley , Regulação para Cima/efeitos dos fármacos
17.
Endocrinology ; 156(1): 268-79, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25375034

RESUMO

We previously demonstrated that advanced glycation-end products (AGEs) promote the pathological progression of diabetic nephropathy by decreasing silent information regulator 2-related protein 1 (Sirt1) expression in glomerular mesangial cells (GMCs). Here, we investigated whether AGEs-receptor for AGEs (RAGE) system down-regulated Sirt1 expression through ubiquitin-proteasome pathway and whether Sirt1 ubiquitination affected fibronectin (FN) and TGF-ß1, 2 fibrotic indicators in GMCs. Sirt1 was polyubiquitinated and subsequently degraded by proteasome. AGEs increased Sirt1 ubiquitination and proteasome-mediated degradation, shortened Sirt1 half-life, and promoted FN and TGF-ß1 expression. Ubiquitin-specific protease 22 (USP22) reduced Sirt1 ubiquitination and degradation and decreased FN and TGF-ß1 expression in GMCs under both basal and AGEs-treated conditions. USP22 depletion enhanced Sirt1 degradation and displayed combined effects with AGEs to further promote FN and TGF-ß1 expression. RAGE functioned crucial mediating roles in these processes via its C-terminal cytosolic domain. Inhibiting Sirt1 by EX-527 substantially suppressed the down-regulation of FN and TGF-ß1 resulting from USP22 overexpression under both normal and AGEs-treated conditions, eventually leading to their up-regulation in GMCs. These results indicated that the AGEs-RAGE system increased the ubiquitination and subsequent proteasome-mediated degradation of Sirt1 by reducing USP22 level, and AGEs-RAGE-USP22-Sirt1 formed a cascade pathway that regulated FN and TGF-ß1 level, which participated in the pathological progression of diabetic nephropathy.


Assuntos
Fibronectinas/metabolismo , Regulação da Expressão Gênica/fisiologia , Produtos Finais de Glicação Avançada/metabolismo , Receptores Imunológicos/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Fibronectinas/genética , Masculino , Ratos , Ratos Sprague-Dawley , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/genética , Sirtuína 1/genética , Sirtuína 1/metabolismo , Tioléster Hidrolases/genética , Tioléster Hidrolases/metabolismo , Fator de Crescimento Transformador beta1/genética
18.
Neurochem Res ; 40(1): 186-94, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25424966

RESUMO

Oxidative stress and blood-brain barrier (BBB) disruption play important roles in cerebral ischemic pathogenesis and may represent targets for treatment. Earlier studies have shown that osthole, a main active constituent isolated from Cnidium monnieri (L.) Cusson, could be considered as an attractive therapeutic agent in the treatment of ischemic stroke. However, the mechanism underlying the protective effect remains vague. In this study we aimed to investigate the effect of osthole on transient cerebral ischemia as well as its mechanism(s) in C57 BL/6 J mice. Mice were subjected to transient global cerebral ischemia induced by bilateral common carotid artery occlusion for 25 min. Behavioral test was performed at 4 days after ischemia, followed by assessment of neuronal loss in hippocampal CA1 region. Osthole significantly improved the cognitive ability and enhanced the survival of pyramidal neurons in the CA1 region of mice after lesion. Further studies showed that osthole attenuated the permeation of BBB, which may contribute to antioxidative effect by increasing the superoxide dismutase activity and decreasing the malondialdehyde level in model mice. Further studies revealed that osthole obviously up-regulated the protein levels of nuclear factor erythroid 2-related factor 2/heme oxygenase 1 in HT22 cells. In conclusion, our findings indicated that osthole exerts neuroprotective effects against global cerebral ischemia injury by reducing oxidative stress injury and reserving the disruption of BBB, which may be attributed to elevating the protein levels of Nrf2 and HO-1.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Cumarínicos/farmacologia , Ataque Isquêmico Transitório/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/farmacologia , Nootrópicos/farmacologia , Animais , Células Cultivadas , Heme Oxigenase-1/metabolismo , Hipocampo/patologia , Ataque Isquêmico Transitório/patologia , Ataque Isquêmico Transitório/psicologia , Masculino , Malondialdeído/metabolismo , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Superóxido Dismutase/metabolismo
19.
Zhong Yao Cai ; 37(2): 288-93, 2014 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-25095353

RESUMO

OBJECTIVE: To study the prevention effect of Huoluotongnao tablet on stroke. METHODS: Bilateral common carotid artery ligation and reperfusion injury model and reperfusion injury in focal cerebral ischemia-induced thrombosis line method rat model were used. RESULTS: Huoluotongnao tablet could significantly reduce the pathological injury of rat brain tissue changes of these two models, and increase the activity of SOD and decrease the content of MDA in the brain tissue and plasma of rats. The brain water content of treatment groups were significantly reduced. The behavioral index and cerebral infarction range index were effectively improved in the middle cerebral artery occlusion reperfusion model rats. CONCLUSION: Huoluotongnao tablet has certain prevention effect on stroke.


Assuntos
Isquemia Encefálica/prevenção & controle , Medicamentos de Ervas Chinesas/farmacologia , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Isquemia Encefálica/metabolismo , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/isolamento & purificação , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/prevenção & controle , Masculino , Malondialdeído/sangue , Malondialdeído/metabolismo , Fármacos Neuroprotetores/isolamento & purificação , Plantas Medicinais/química , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Superóxido Dismutase/sangue , Superóxido Dismutase/metabolismo , Comprimidos
20.
CNS Neurosci Ther ; 20(9): 840-50, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24922524

RESUMO

AIMS: Oxidative stress (OS) plays an important role in the pathogenesis of neurodegenerative diseases, including Alzheimer's disease (AD). This study was designed to uncover the cellular and biochemical mechanisms underlying the neuroprotective effects of tacrine-3-caffeic acid (T3CA), a novel promising multifunctional anti-Alzheimer's dimer, against OS-induced neuronal death. METHODS AND RESULTS: T3CA protected HT22 cells against high-concentration-glutamate-induced cell death in time- and concentration-dependent manners and potently attenuated glutamate-induced intracellular reactive oxygen species (ROS) production as well as mitochondrial membrane-potential (ΔΨ) disruption. Besides, T3CA significantly induced nuclear factor erythroid 2-related factor 2 (Nrf2) nuclear translocation and increased its transcriptional activity, which were demonstrated by Western blotting, immunofluorescence, and antioxidant response element (ARE)-luciferase reporter gene assay. Further studies showed that T3CA potently up-regulated heme oxygenase-1 (HO-1), an endogenous antioxidative enzyme and a downstream effector of Nrf2, at both mRNA and protein levels. The neuroprotective effects of T3CA were partially reversed by brusatol, which reduced protein level of Nrf2, or by inhibiting HO-1 with siRNA or ZnPP-IX, a specific inhibitor of HO-1. CONCLUSIONS: Taken together, these results clearly demonstrate that T3CA protects neurons against OS-induced cell death partially through Nrf2/ARE/HO-1 signaling pathway, which further supports that T3CA might be a promising novel therapeutic agent for OS-associated diseases.


Assuntos
Ácidos Cafeicos/farmacologia , Heme Oxigenase-1/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Neurônios/efeitos dos fármacos , Nootrópicos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Tacrina/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Transformada , Proteínas do Citoesqueleto/metabolismo , Ácido Glutâmico/farmacologia , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transfecção
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