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1.
Eur Heart J ; 39(1): 60-69, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-28549109

RESUMEN

Aims: Rapid over-activation of ß-adrenergic receptor (ß-AR) upon stress leads to cardiac inflammation, a prevailing factor that underlies heart injury. However, mechanisms by which acute ß-AR stimulation induce cardiac inflammation still remain unknown. Here, we set out to identify the crucial role of inflammasome/interleukin (IL)-18 in initiating and maintaining cardiac inflammatory cascades upon ß-AR insult. Methods and results: Male C57BL/6 mice were injected with a single dose of ß-AR agonist, isoproterenol (ISO, 5 mg/kg body weight) or saline subcutaneously. Cytokine array profiling demonstrated that chemokines dominated the initial cytokines upregulation specifically within the heart upon ß-AR insult, which promoted early macrophage infiltration. Further investigation revealed that the rapid inflammasome-dependent activation of IL-18, but not IL-1ß, was the critical up-stream regulator for elevated chemokine expression in the myocardium upon ISO induced ß1-AR-ROS signalling. Indeed, a positive correlation was observed between the serum levels of norepinephrine and IL-18 in patients with chest pain. Genetic deletion of IL-18 or the up-stream inflammasome component NLRP3 significantly attenuated ISO-induced chemokine expression and macrophage infiltration. In addition, IL-18 neutralizing antibodies selectively abated ISO-induced chemokines, proinflammatory cytokines and adhesion molecules but not growth factors. Moreover, blocking IL-18 early after ISO treatment effectively attenuated cardiac inflammation and fibrosis. Conclusion: Inflammasome-dependent activation of IL-18 within the myocardium upon acute ß-AR over-activation triggers cytokine cascades, macrophage infiltration and pathological cardiac remodelling. Blocking IL-18 at the early stage of ß-AR insult can successfully prevent inflammatory responses and cardiac injuries.


Asunto(s)
Agonistas Adrenérgicos beta/farmacología , Inflamación/metabolismo , Interleucina-18/metabolismo , Miocardio/metabolismo , Receptores Adrenérgicos beta/metabolismo , Animales , Citocinas/metabolismo , Fibrosis/metabolismo , Corazón/efectos de los fármacos , Humanos , Inflamasomas/efectos de los fármacos , Inflamasomas/metabolismo , Isoproterenol/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Miocardio/inmunología , Estrés Fisiológico/efectos de los fármacos , Estrés Fisiológico/fisiología
2.
Am J Physiol Heart Circ Physiol ; 306(11): H1569-81, 2014 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-24705558

RESUMEN

Inhibition of matrix metalloproteinases-2 (MMP-2) activation renders cardioprotection from ischemia/reperfusion (I/R) injury; however, the signaling pathways involved have not been fully understood. Intermittent hypobaric hypoxia (IHH) has been shown to enhance myocardial tolerance to I/R injury via triggering intrinsic adaptive responses. Here we investigated whether IHH protects the heart against I/R injury via the regulation of MMP-2 and how the MMP-2 is regulated. IHH (Po2 = 84 mmHg, 4-h/day, 4 wk) improved postischemic myocardial contractile performance, lactate dehydrogenase (LDH) release, and infarct size in isolated perfused rat hearts. Moreover, IHH reversed I/R-induced MMP-2 activation and release, disorders in the levels of MMP-2 regulators, peroxynitrite (ONOO(-)) and tissue inhibitor of metalloproteinase-4 (TIMP-4), and loss of the MMP-2 targets α-actinin and troponin I. This protection was mimicked, but not augmented, by a MMP inhibitor doxycycline and lost by the α1-adrenoceptor (AR) antagonist prazosin. Furthermore, IHH increased myocardial α1A-AR and α1B-AR density but not α1D-AR after I/R. Concomitantly, IHH further enhanced the translocation of PKC epsilon (PKCε) and decreased the release of mitochondrial cytochrome c due to I/R via the activation of α1B-AR but not α1A-AR or α1D-AR. IHH-conferred cardioprotection in the postischemic contractile function, LDH release, MMP-2 activation, and nitrotyrosine as well as TIMP-4 contents were mimicked but not additive by α1-AR stimulation with phenylephrine and were abolished by an α1B-AR antagonist chloroethylclonidine and a PKCε inhibitor PKCε V1-2. These findings demonstrate that IHH exerts cardioprotection through attenuating excess ONOO(-) biosynthesis and TIMP-4 loss and sequential MMP-2 activation via the activation of α1B-AR/PKCε pathway.


Asunto(s)
Hipoxia/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Isquemia Miocárdica/metabolismo , Miocardio/metabolismo , Receptores Adrenérgicos alfa 1/metabolismo , Daño por Reperfusión/metabolismo , Actinina/metabolismo , Antagonistas de Receptores Adrenérgicos alfa 1/farmacología , Animales , Doxiciclina/farmacología , Masculino , Prazosina/farmacología , Proteína Quinasa C-epsilon/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Inhibidores Tisulares de Metaloproteinasas/metabolismo , Inhibidor Tisular de Metaloproteinasa-4
3.
Clin Exp Pharmacol Physiol ; 41(1): 58-66, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24107096

RESUMEN

1. Chronic injection with the ß-adrenoceptor (ß-AR) agonist isoproterenol (ISO) has been commonly used as an animal model of ß-AR-induced cardiac remodelling and heart failure. This ISO-treated model usually exhibits significantly decreased conscious heart rate (HR). However, the HR in treatment groups is usually adjusted to the same levels by anaesthesia to assess cardiac geometry and function. In the present study, we report a method of echocardiographic assessment that represents the true cardiac geometry and function under conditions of ISO withdrawal. 2. Briefly, C57BL/6 mice were treated with 5 mg/kg per day ISO for 12 weeks. Cardiac geometry and function were assessed by high-resolution echocardiography in vehicle (saline) - and ISO-treated mice that were either conscious or anaesthetized using different concentrations of isoflurane. 3. The cardiac ß-AR response was decreased in ISO-treated mice, as evidenced by markedly decreased conscious HR. Vehicle- and ISO-treated mice did not differ in terms of cardiac geometry or function when HR was adjusted to the same level (400 b.p.m.) in both treatment groups, but cardiac geometry and function did differ when a low (1%) rather than high (1.5% or 2%) isoflurane concentration was used to adjust HR. Furthermore, 3 day ISO withdrawal eliminated the difference in conscious HR between the two groups. In addition, the groups differed in cardiac geometry and function regardless of the isoflurane concentration used. 4. In conclusion, using isoflurane to decrease the HR of treated groups to the same level may mask left ventricular dysfunction in ISO-treated mice. Withdrawal of ISO eliminated the difference in basal HR between the ISO-treated and control groups on echocardiography, allowing a more accurate assessment of cardiac pathological and functional changes.


Asunto(s)
Agonistas Adrenérgicos beta , Ecocardiografía/métodos , Insuficiencia Cardíaca/inducido químicamente , Insuficiencia Cardíaca/diagnóstico por imagen , Frecuencia Cardíaca/efectos de los fármacos , Isoproterenol , Anestesia por Inhalación , Anestésicos por Inhalación , Animales , Insuficiencia Cardíaca/patología , Pruebas de Función Cardíaca , Hemodinámica/efectos de los fármacos , Isoflurano , Masculino , Ratones , Ratones Endogámicos C57BL , Miocardio/patología , Remodelación Ventricular
4.
Clin Exp Pharmacol Physiol ; 37(8): 826-32, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20456423

RESUMEN

1. The mouse is the preferred species for gene targeting as a tool for research into the heart and heart development. The developmental features of the geometry and function of the heart in young mice are not well defined and cardiac functional responses following stimulation of beta-adrenoceptors have not been investigated. 2. Using the VisualSonic (Toronto, ON, Canada) high-resolution ultrasound system, we investigated male C57BL/6 mice at 0.5-18 weeks of age. Echocardiography was performed at baseline and repeated after administration of the beta-adrenoceptor agonist isoproterenol (4 microg/kg). 3. The geometry of the left ventricle became mature 2 weeks after birth. A significant decline in left ventricular contractile function occurred at 2-3 weeks of age. 4. Inotropic and chronotropic responses to isoproterenol were significantly weaker in mice at a weaning age < 2 weeks compared with adult mice (heart rate increment 3 +/- 3% vs 32 +/- 4%, respectively; fractional shortening increment 19 +/- 5% vs 78 +/- 8%, respectively; P < 0.001). 5. In conclusion, significant changes occur in mice from birth until weaning with respect to the topography, function and beta-adrenoceptor responsiveness of the heart. The results of the present study provide a reference point for future studies in genotyping cardiac function during the postnatal phase in genetically engineered mice.


Asunto(s)
Agonistas Adrenérgicos beta/farmacología , Corazón/anatomía & histología , Corazón/crecimiento & desarrollo , Miocardio/metabolismo , Receptores Adrenérgicos beta/efectos de los fármacos , Receptores Adrenérgicos beta/fisiología , Envejecimiento/fisiología , Animales , Animales Recién Nacidos , Ecocardiografía , Prueba de Esfuerzo , Frecuencia Cardíaca/efectos de los fármacos , Ventrículos Cardíacos/anatomía & histología , Isoproterenol/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía , Contracción Miocárdica/fisiología , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados
5.
Clin Exp Pharmacol Physiol ; 37(3): 296-302, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19719751

RESUMEN

1. Insulin-like growth factor (IGF)-I plays an important role in the pathogenesis of heart disease and has been shown to strongly induce the proliferation of cardiac fibroblasts (CFs). It remains unknown whether 14-3-3 proteins, which are associated the regulation of signal transduction, affect IGF-I-induced CF proliferation. 2. In the present study, we investigated the effects of 14-3-3 proteins on CF proliferation in response to IGF-I. Proliferation of CFs was determined by cell counting and a bromodeoxyuridine incorporation assay. Phosphorylation of signalling molecules was evaluated by western blottling. Activity of nuclear factor of activated T cells (NFAT) was examined using a dual luciferase reporter gene assay and immunofluorescence. 3. It was found that adenovirus-mediated transfection of YFP-R18 peptide (AdR18), a known inhibitor of 14-3-3, significantly enhanced IGF-I-induced CF proliferation. This potentiation arose from an increase in phosphorylation of phosphatidylinositol 3-kinase (PI3-K) and AKT (protein kinase B), inactivation of glycogen synthesis kinase (GSK) 3beta and increased NFAT activity. 4. Collectively, the results of the present study suggest that 14-3-3 proteins inhibit IGF-I-induced CF proliferation via a PI3-K-dependent NFAT signalling pathway. This finding may contribute to our understanding of the function of 14-3-3 proteins in the heart.


Asunto(s)
Proteínas 14-3-3/metabolismo , Proliferación Celular , Fibroblastos/citología , Factor I del Crecimiento Similar a la Insulina/farmacología , Miocardio/citología , Fosfatidilinositol 3-Quinasa/fisiología , Proteínas 14-3-3/antagonistas & inhibidores , Animales , Línea Celular , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Fibroblastos/enzimología , Fibroblastos/metabolismo , Humanos , Ratones , Ratones Endogámicos C57BL , Miocardio/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología
6.
Sheng Li Xue Bao ; 59(2): 175-82, 2007 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-17437040

RESUMEN

To test the hypothesis that AMP-activated protein kinase (AMPK) is possibly the downstream signaling molecule of certain subtypes of adrenergic receptor (AR) in the heart, we evaluated AMPK activation mediated by ARs in H9C2 cells, a rat cardiac source cell line, and rat hearts. The AMPK-alpha subunit and the phosphorylation level of Thr(172)-AMPK-alpha subunit were subjected to Western blot analysis. Osmotic minipumps filled with norepinephrine (NE), phenylephrine (PE) or vehicle [0.01% (W/V) vitamin C solution] were implanted into male Sprague-Dawley rats subcutaneously. The pumps delivered NE or PE continuously at the rate of 0.2 mg/kg per hour. After 7-day infusion, the activity of AMPK was examined following immunoprecipitation with anti-AMPK-alpha antibody. At the cellular level, we found that NE elevated AMPK phosphorylation level in a dose- and time-dependent manner, with the maximal effect at 10 micromol/L NE after 10-minute treatment. This effect was insensitive to propranolol, a specific beta-AR antagonist, but abolished by prazosin, an alpha(1)-AR antagonist, suggesting that alpha(1)-AR but not beta-AR mediated the phosphorylation of AMPK. Moreover, the results from rat models of 7-day-infusion of AR agonists demonstrated that the activity of AMPK was significantly higher in NE (7.4-fold) and PE (6.0-fold) infusion groups than that in the vehicle group (P<0.05, n=6). On the other hand, no obvious cardiac hypertrophy and tissue fibrosis changes were observed in PE-infused rats. Taken together, our results demonstrate that alpha(1)-AR stimulation enhances the activity of AMPK, indicating an important role of alpha(1)-AR stimulation in the regulation of AMPK in the heart. Understanding the activation of AMPK mediated by alpha(1)-AR might have clinical implications in the therapy of heart failure.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Miocardio/metabolismo , Receptores Adrenérgicos alfa/fisiología , Animales , Línea Celular , Ventrículos Cardíacos , Masculino , Miocardio/citología , Norepinefrina/farmacología , Fenilefrina/farmacología , Fosforilación , Ratas , Ratas Sprague-Dawley
7.
Phytochemistry ; 61(4): 409-13, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12377235

RESUMEN

Four phenylpropanoid esters, cimiracemates A-D (1-4), along with three known compounds, isoferulic acid, ferulic acid and methyl caffeate were isolated from the EtOAc fraction of the rhizome of Cimicifuga racemosa. The structures of the esters were elucidated by means of spectral data, including 2D NMR spectroscopy.


Asunto(s)
Cimicifuga/química , Ésteres/química , Ésteres/aislamiento & purificación , Fenilpropionatos/química , Fenilpropionatos/aislamiento & purificación , Rizoma/química , Estructura Molecular
8.
Anticancer Res ; 23(5A): 3699-702, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14666666

RESUMEN

BACKGROUND: Ginger root (Zingiber officinale) has been used traditionally for the treatment of gastrointestinal ailments such as motion sickness, dyspepsia and hyperemesis gravidarum, and is also reported to have chemopreventative activity in animal models. The gingerols are a group of structurally related polyphenolic compounds isolated from ginger and known to be the active constituents. Since Helicobacter pylori (HP) is the primary etiological agent associated with dyspepsia, peptic ulcer disease and the development of gastric and colon cancer, the anti-HP effects of ginger and its constituents were tested in vitro. MATERIALS AND METHODS: A methanol extract of the dried powdered ginger rhizome, fractions of the extract and the isolated constituents, 6-,8-,10-gingerol and 6-shogoal, were tested against 19 strains of HP, including 5 CagA+ strains. RESULTS: The methanol extract of ginger rhizome inhibited the growth of all 19 strains in vitro with a minimum inhibitory concentration range of 6.25-50 micrograms/ml. One fraction of the crude extract, containing the gingerols, was active and inhibited the growth of all HP strains with an MIC range of 0.78 to 12.5 micrograms/ml and with significant activity against the CagA+ strains. CONCLUSION: These data demonstrate that ginger root extracts containing the gingerols inhibit the growth of H. pylori CagA+ strains in vitro and this activity may contribute to its chemopreventative effects.


Asunto(s)
Catecoles/farmacología , Alcoholes Grasos/farmacología , Helicobacter pylori/efectos de los fármacos , Zingiber officinale/química , Antígenos Bacterianos/biosíntesis , Proteínas Bacterianas/biosíntesis , Catecoles/química , Alcoholes Grasos/química , Helicobacter pylori/crecimiento & desarrollo , Helicobacter pylori/metabolismo , Metanol/química , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Extractos Vegetales/farmacología
9.
J Agric Food Chem ; 50(24): 7022-8, 2002 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-12428954

RESUMEN

The roots/rhizomes of Cimicifuga racemosa L. (Nutt.) (black cohosh) have traditionally been used to treat menopausal symptoms through an unknown mechanism of action. In an effort to determine if black cohosh had additional health benefits, methanol extracts were investigated for their potential to scavenge reactive oxygen species and to protect against menadione-induced DNA damage. These extracts effectively scavenged 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals. In addition, the extracts showed dose-dependent decreases in DNA single-strand breaks and oxidized bases induced by the quinone menadione using the comet (single-cell gel electrophoresis assay) and fragment length associated repair enzyme assays, respectively. Bioassay-directed fractionation of the methanolic extracts using the DPPH assay as a monitor led to the isolation of nine antioxidant active compounds: caffeic acid (1), methyl caffeate (2), ferulic acid (3), isoferulic acid (4), fukinolic acid (5), cimicifugic acid A (6), cimicifugic acid B (7), cimicifugic acid F (8), cimiracemate A (9), and cimiracemate B (10). Six of these antioxidants were found to reduce menadione-induced DNA damage in cultured S30 breast cancer cells with the following order of potency: methyl caffeate (2) > caffeic acid (1) > ferulic acid (3) > cimiracemate A (9) > cimiracemate B (10) > fukinolic acid (5). These data suggest that black cohosh can protect against cellular DNA damage caused by reactive oxygen species by acting as antioxidants.


Asunto(s)
Antioxidantes/aislamiento & purificación , Cimicifuga/química , Daño del ADN/efectos de los fármacos , Depuradores de Radicales Libres/aislamiento & purificación , Especies Reactivas de Oxígeno/química , Vitamina K 3/farmacología , Antioxidantes/farmacología , Compuestos de Bifenilo , Neoplasias de la Mama , Receptor alfa de Estrógeno , Depuradores de Radicales Libres/farmacología , Expresión Génica , Humanos , Metanol , Picratos/química , Extractos Vegetales/química , Receptores de Estrógenos/genética , Transfección , Células Tumorales Cultivadas
10.
Sheng Li Xue Bao ; 55(3): 251-4, 2003 Jun 25.
Artículo en Zh | MEDLINE | ID: mdl-12817289

RESUMEN

The expression of beta-adrenergic receptor subtypes and its effect on neonatal rat cardiac fibroblast proliferation were investigated by radioligand binding assay and [(3)H]-thymidine incorporation analysis, respectively. The results indicated that there was no significant difference in the beta-adrenergic receptor density (B(max)) and affinity (K(D)) between cardiomyocytes and cardiac fibroblasts. The [(125)I]-pindolol competitive inhibition curves (ICI 118551 and CGP 20712A) were significantly better fit in a one-site model in membrane preparation of cardiac fibroblasts. In cultured cardiac fibroblasts, 0.1 micromol/L isoproterenol-induced [(3)H]-thymidine incorporation was completely inhibited by a selective beta (2)-AR antagonist ICI 118551, or a non-selective beta-AR antagonist propranolol, but not by CGP 20712A, a selective beta(1)-AR antagonist. These results suggest that isoproterenol-induced cardiac fibroblast proliferation is mediated by beta(2)-AR, the preponderant beta-AR subtype in cardiac fibroblasts.


Asunto(s)
Fibroblastos/citología , Miocitos Cardíacos/citología , Receptores Adrenérgicos beta 2/metabolismo , Receptores Adrenérgicos beta 2/fisiología , Animales , Animales Recién Nacidos , Proliferación Celular , Células Cultivadas , Fibroblastos/metabolismo , Miocitos Cardíacos/metabolismo , Ratas , Ratas Wistar , Receptores Adrenérgicos beta 2/genética
11.
Sheng Li Xue Bao ; 56(2): 224-9, 2004 Apr 25.
Artículo en Zh | MEDLINE | ID: mdl-15127134

RESUMEN

The aim of the present study was to investigate the effects of beta-adrenergic receptor (beta-AR) activation on metabolism in cultured neonatal rat cardiomyocytes. The protein synthesis and total protein content of cardiomyocytes were determined by [(3)H]-leucine incorporation and BCA protein content assay. Cardiomyocyte glucose uptake was measured by [(3)H]-2-deoxy-D-glucose uptake analysis. Adenosine monophosphate activated protein kinase (AMPK) phosphorylation was detected by Western blot. The results showed that sustained stimulation with isoproterenol (ISO), a beta-adrenoceptor agonist, had no effect on [(3)H]-leucine incorporation and total protein content in cardiomyocytes. With beta-AR activation by ISO or NE (pretreated with a selective blocker of the alpha(1)-adrenoceptor prazosin) for 48 h, both the glucose uptake and AMPK phosphorylation increased significantly compared with unstimulated cardiomyocytes. These results suggest that although sustained beta-AR activation has no effect on cardiomyocyte protein metabolism, glucose uptake and AMPK activity are increased significantly. The role of these beta-AR activation-induced changes in cardiac hypertrophy remains to be further investigated.


Asunto(s)
Glucosa/metabolismo , Proteínas Musculares/biosíntesis , Miocitos Cardíacos/metabolismo , Proteínas Quinasas Activadas por AMP , Animales , Animales Recién Nacidos , Células Cultivadas , Complejos Multienzimáticos/metabolismo , Miocitos Cardíacos/citología , Proteínas Serina-Treonina Quinasas/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores Adrenérgicos beta
12.
Br J Pharmacol ; 159(8): 1598-607, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20050850

RESUMEN

BACKGROUND AND PURPOSE: Inflammatory response and cytokine activation are markedly stimulated after myocardial infarction, and contribute to cardiac remodelling. Interleukin-6 (IL-6), a pro-inflammatory cytokine, has pleiotropic effects on cardiac remodelling. Adenosine, released by all cell types, binds to a class of G protein-coupled receptors to induce various cardiovascular effects. The aim of this work was to investigate whether activation of adenosine receptors, particularly A(2B) adenosine receptors, could stimulate IL-6 secretion in cardiac fibroblasts (CFs). EXPERIMENTAL APPROACH: elisa was used to assess IL-6 concentration in supernatant, and immunostaining was used to analyse IL-6 protein level in CFs. The levels of phosphorylated and total p38, extracellular signal-regulated kinase, c-Jun N-terminal kinase and protein kinase C-delta (PKC-delta) were determined by Western blot analysis. KEY RESULTS: Adenosine-5'-N-ethyluronamide (NECA), a stable adenosine analogue, dose- and time-dependently stimulated IL-6 secretion in CFs. The effect of NECA was dose-dependently inhibited by an A(2B) antagonist, and silencing of the A(2B) receptor also inhibited IL-6 secretion. By using PKC isoform-selective inhibitors and translocation peptide inhibitors, the PKC-delta isoform was found to be involved in the up-regulation of IL-6 production. Inhibition of p38 by SB203580, and adenoviral transfer of dominant-negative p38 inhibited NECA-induced IL-6 production. Furthermore, PKC-delta functioned as an upstream regulator of p38 MAPK in this process. CONCLUSIONS AND IMPLICATIONS: We demonstrated a novel relationship between adenosine and IL-6 secretion, in that IL-6 secretion induced by NECA was mediated by adenosine A(2B) receptor activation in CFs and was dependent on a PKCdelta-P38 pathway.


Asunto(s)
Agonistas del Receptor de Adenosina A2 , Adenosina-5'-(N-etilcarboxamida)/farmacología , Interleucina-6/metabolismo , Miocardio/metabolismo , Proteína Quinasa C-delta/metabolismo , Transducción de Señal , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Secuencia de Bases , Células Cultivadas , Cartilla de ADN , Ensayo de Inmunoadsorción Enzimática , Fibroblastos/enzimología , Fibroblastos/metabolismo , Imidazoles/farmacología , Masculino , Ratones , Ratones Endogámicos BALB C , Microscopía Fluorescente , Miocardio/citología , Miocardio/enzimología , Células 3T3 NIH , Fosforilación , Piridinas/farmacología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores
13.
J Nat Prod ; 70(6): 1016-23, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17555351

RESUMEN

Extracts from the roots and rhizomes of black cohosh (Cimicifuga racemosa) are widely used as dietary supplements to alleviate menopausal symptoms. State-of-the-art quality control measures involve phytochemical fingerprinting of the triterpene glycosides for species identification and chemical standardization by HPLC. In the course of developing materials and methods for standardization procedures, the major C. racemosa triterpene glycoside (1) was isolated and initially thought to be cimicifugoside (2). Detailed HR-LC-MS and 1D and 2D NMR analysis of 1 and 2 unambiguously revealed that 1 is the chlorine-containing derivative of 2, namely, 25-chlorodeoxycimigenol-3-O-beta-d-xyloside. Accordingly, HPLC profiles of black cohosh preparations require revision of the assignments of the chlorinated (1) and nonchlorinated (2) pair. Besides explaining the substantial shift in polarity (DeltatR[RP-18] ca. 20 min), 25-deoxychlorination opens a new pathway of structural diversification in triterpene glycoside chemistry. As chemical conversion of 2 into 1 could be demonstrated, deoxychlorination may be interpreted as artifact formation. Simultaneously, however, it is a potentially significant pathway for the gastric in vivo conversion ("nature's prodrug") of the relatively polar triterpene glycosides into significantly less polar chlorinated derivatives with altered pharmacological properties.


Asunto(s)
Cloro/química , Cimicifuga/química , Glicósidos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales/química , Triterpenos/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Cimicifuga/efectos de los fármacos , Glicósidos/química , Glicósidos/farmacología , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Extractos Vegetales/química , Extractos Vegetales/farmacología , Raíces de Plantas/química , Rizoma/química , Triterpenos/química , Triterpenos/farmacología , Virginia
14.
J Mol Cell Cardiol ; 40(3): 384-93, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16466739

RESUMEN

We previously reported that cardiac fibroblasts, but not cardiomyocytes, are served as the predominant source of IL-6 after isoproterenol stimulation in mouse myocardium. The present study investigated the molecular mechanism of isoproterenol-mediated secretion of IL-6 in mouse cardiac fibroblasts. Treatment of cells with isoproterenol-induced a time-dependent accumulation of IL-6, which was mediated by beta(2)-adrenergic receptor (AR), the preponderant beta-AR subtype in cardiac fibroblasts. Isoproterenol-induced secretion of IL-6 was mainly mediated by Gs-AC-cAMP signaling cascade and could be negatively regulated by Gi and PI3K. Surprisingly, the effect of cAMP was independent of protein kinase A and the exchange protein directly activated by cAMP (Epac)-Rap1 pathway and suggests the existence of a novel cAMP-dependent mechanism. p38 MAPK inhibitor SB203580, but not extracellular regulated protein kinase inhibitor, abrogated isoproterenol-induced IL-6 release in cardiac fibroblasts and mouse myocardium. Interestingly, p38 MAPK could also be positively regulated by Gs-AC-cAMP but negatively regulated by Gi-PI3K pathway. Finally, multiple transcription factors (AP-1, C/EBP, NF-kappaB and CREB) regulating the IL-6 gene are activated in response to isoproterenol stimulation, which may provide essential linkage between upstream cAMP-p38 MAPK signaling cascade and downstream IL-6 gene transcription. The present results suggest that beta(2)-AR mediates IL-6 production through a noncanonical cAMP responsible pathway and p38 MAPK.


Asunto(s)
AMP Cíclico/metabolismo , Fibroblastos/enzimología , Interleucina-6/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Agonistas Adrenérgicos beta/farmacología , Animales , Animales Recién Nacidos , Western Blotting , Células Cultivadas , AMP Cíclico/análisis , Proteínas Quinasas Dependientes de AMP Cíclico/análisis , Proteínas Quinasas Dependientes de AMP Cíclico/biosíntesis , Ensayo de Inmunoadsorción Enzimática , Fibroblastos/metabolismo , Técnica del Anticuerpo Fluorescente Indirecta , Colorantes Fluorescentes , Isoproterenol/farmacología , Cinética , Ratones , Ratones Endogámicos BALB C , Modelos Biológicos , Miocardio/citología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rodaminas
15.
Biochem Biophys Res Commun ; 337(4): 1139-44, 2005 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-16229818

RESUMEN

Though known as a sensor of energy balance, AMP-activated protein kinase (AMPK) was recently shown to limit damage and apoptotic activity and contribute to the late preconditioning in heart. Interleukin-6 was also reported to involve in anti-apoptosis and cardio-protection in myocardium. Interestingly, both AMPK activity and IL-6 level were increased in response to ischemia, hypertrophy and oxidative stress. To determine whether AMPK activation will promote IL-6 production, cardiac fibroblasts (CFs) from mice were incubated with AMPK activator, 5-aminoimidazole-4-carboxamide-1-4-ribofuranoside (AICAR). The results demonstrated that AICAR time and dose-dependently stimulated IL-6 production by ELISA and immunofluorescence. Pretreatment with p38 mitogen-activated protein kinase (MAPK) inhibitor blocked AICAR-induced IL-6 production; furthermore, AICAR-activated p38 MAPK phosphorylation by Western blot. To confirm that the increase in IL-6 production is ascribed to AMPK activation, we used another known AMPK activator, metformin. It also dose-dependently potentiated IL-6 production in CFs, and this potentiation could be reversed by p38 MAPK inhibitor. In conclusion, AMPK activation promoted IL-6 production in CFs via p38 MAPK-dependent pathway.


Asunto(s)
Envejecimiento/fisiología , Aminoimidazol Carboxamida/análogos & derivados , Interleucina-6/biosíntesis , Complejos Multienzimáticos/metabolismo , Miocardio/citología , Miocardio/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Ribonucleótidos/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Proteínas Quinasas Activadas por AMP , Aminoimidazol Carboxamida/farmacología , Animales , Células Cultivadas , Activación Enzimática/efectos de los fármacos , Fibroblastos , Masculino , Ratones , Ratones Endogámicos BALB C
16.
Acta Pharmacol Sin ; 24(4): 327-31, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12676072

RESUMEN

AIM: To study the functional alpha1-adrenergic receptor (alpha1-AR) subtypes in human right gastroepiploic artery (RGA). METHODS: The effects of alpha2-AR, alpha1-AR, and alpha1-AR subtype selective antagonists on norepinephrine (NE)-induced vasoconstriction in isolated human RGA were observed by contractile function experiment. RESULTS: Cumulative concentration-response curves for NE were competitively antagonized in RGA by alpha2-AR selective antagonist yohimbine (pA2 6.82+/-0.28, slope 1.12+/-0.40),alpha1-AR selective antagonist prazosin (pA2 9.77+/-0.22, slope 0.90+/-0.22),alpha1A-AR selective antagonists RS17053 (pA2 8.42+/-0.20, slope 0.93+/-0.20) and 5-MU (pA2 8.42+/-0.22, slope 0.88+/-0.18),alpha1D-AR selective antagonist BMY7378 (pA2 6.84+/-0.32, slope 1.05+/-0.17), and alpha1A-,alpha1B-AR selective antagonist WB4101 (pA2 8.88+/-0.20, slope 1.15+/-0.16). The correlation coefficients between these pA2 values of alpha1-AR selective antagonists with pKi values of which obtained from alpha1A-, alpha1B- and alpha1D-AR cloned cells are 0.95, 0.82, and 0.42. After the vessels were pretreated by chlorethylclonidine (CEC), an alpha1B- and alpha1D-AR irreversible alkylating agent, the pD2 values were changed from 5.9+/-0.5 to 5.6+/-0.6 and the maximal contraction was changed from (8.9+/-3.2) g to (8.0+/-3.2) g, respectively. The difference was not significant. CONCLUSION: In human RGA, the contraction response is mainly mediated by alpha1-AR, of which alpha1A-AR plays an important role, whereas alpha1B- and alpha1D-AR are not involved in the contraction response.


Asunto(s)
Antagonistas de Receptores Adrenérgicos alfa 1 , Arteria Gastroepiploica/fisiología , Indoles/farmacología , Contracción Muscular/efectos de los fármacos , Adulto , Anciano , Dioxanos/farmacología , Femenino , Arteria Gastroepiploica/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/fisiología , Piperazinas/farmacología , Receptores Adrenérgicos alfa 1
17.
J Nat Prod ; 65(10): 1391-7, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12398533

RESUMEN

Eight new and 13 known triterpene glycosides, along with the known compounds glyceryl-1-palmitate and daucosterol-6'-linoleate were isolated from the roots/rhizomes of Cimicifuga racemosa. The new compounds, designated as cimiracemosides I-P (1, 3-9), were determined by spectral analysis to be 7-dehydro-23-epi-12,26-dideoxyacteol-3-O-beta-D-xylopyranoside (1), 12-O-acetyl-25-anhydrocimigenol-3-O-alpha-L-arabinopyranoside (3), 12-O-acetyl-25-anhydrocimigenol-3-O-beta-D-xylopyranoside (4), 4',23-O-diacetylshengmanol-3-O-beta-D-xylopyranoside (5), 4',23-O-diacetylshengmanol-3-O-alpha-L-arabinopyranoside (6), 23-epi-acetylacteol-3-O-alpha-L-arabinopyranoside (7), 4'-O-acetyl-26-deoxyactein (8), and 16beta:23;24:25-diepoxy-12beta-O-acetyl-3beta-hydroxy-9,19-cyclolanost-23,26-olide-O- beta-D-xylopyranoside (9).


Asunto(s)
Cimicifuga/química , Glicósidos/aislamiento & purificación , Triterpenos/aislamiento & purificación , Glicósidos/química , Espectroscopía de Resonancia Magnética , Espectrometría de Masa por Ionización de Electrospray , Triterpenos/química
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