Molecular mechanism of endothelial nitric-oxide synthase activation by Platycodon grandiflorum root-derived saponins

2010 ◽  
Vol 195 (2-3) ◽  
pp. 106-113 ◽  
Author(s):  
Hyung Gyun Kim ◽  
Tran Thi Hien ◽  
Eun Hee Han ◽  
Young Chul Chung ◽  
Hye Gwang Jeong
Keyword(s):  
Nitric Oxide ◽  
Nitric Oxide Synthase ◽  
Molecular Mechanism ◽  
Endothelial Nitric Oxide Synthase ◽  
Platycodon Grandiflorum ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

scholarly journals Caveolin-1 mediates endotoxin inhibition of endothelin-1-induced endothelial nitric oxide synthase activity in liver sinusoidal endothelial cells

2009 ◽  
Vol 297 (5) ◽  
pp. G930-G939 ◽  
Author(s):  
Willson Kwok ◽  
Sang Ho Lee ◽  
Cathy Culberson ◽  
Katarzyna Korneszczuk ◽  
Mark G. Clemens
Keyword(s):  
Nitric Oxide ◽  
Endothelial Cells ◽  
Nitric Oxide Synthase ◽  
Molecular Mechanism ◽  
Endothelial Nitric Oxide Synthase ◽  
Liver Sinusoidal Endothelial Cells ◽  
Caveolin 1 ◽  
Enos Activity ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

Endothelin-1 (ET-1) plays a key role in the regulation of endothelial nitric oxide synthase (eNOS) activation in liver sinusoidal endothelial cells (LSECs). In the presence of endotoxin, an increase in caveolin-1 (Cav-1) expression impairs ET-1/eNOS signaling; however, the molecular mechanism is unknown. The objective of this study was to investigate the molecular mechanism of Cav-1 in the regulation of LPS suppression of ET-1-mediated eNOS activation in LSECs by examining the effect of caveolae disruption using methyl-β-cyclodextrin (CD) and filipin. Treatment with 5 mM CD for 30 min increased eNOS activity (+255%, P < 0.05). A dose (0.25 μg/ml) of filipin for 30 min produced a similar effect (+111%, P < 0.05). CD induced the perinuclear localization of Cav-1 and eNOS and stimulated NO production in the same region. Readdition of 0.5 mM cholesterol to saturate CD reversed these effects. Both the combined treatment with CD and ET-1 (CD + ET-1) and with filipin and ET-1 stimulated eNOS activity; however, pretreatment with endotoxin (LPS) abrogated these effects. Following LPS pretreatment, CD + ET-1 failed to stimulate eNOS activity (+51%, P > 0.05), which contributed to the reduced levels of eNOS-Ser1177 phosphorylation and eNOS-Thr495 dephosphorylation, the LPS/CD-induced overexpression and translocation of Cav-1 in the perinuclear region, and the increased perinuclear colocalization of eNOS with Cav-1. These results supported the hypothesis that Cav-1 mediates the action of endotoxin in suppressing ET-1-mediated eNOS activation and demonstrated that the manipulation of caveolae produces significant effects on ET-1-mediated eNOS activity in LSECs.

Localization of endothelial nitric oxide synthase in the normal and failing human atrial myocardium

1996 ◽  
Vol 54 ◽  
pp. 786-787
Author(s):  
Chi-Ming Wei ◽  
Margarita Bracamonte ◽  
Shi-Wen Jiang ◽  
Richard C. Daly ◽  
Christopher G.A. McGregor ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Heart Failure ◽  
Nitric Oxide Synthase ◽  
Endothelial Nitric Oxide Synthase ◽  
Cardiac Tissues ◽  
Mammalian Tissues ◽  
End Stage Heart Failure ◽  
End Stage ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

Nitric oxide (NO) is a potent endothelium-derived relaxing factor which also may modulate cardiomyocyte inotropism and growth via increasing cGMP. While endothelial nitric oxide synthase (eNOS) isoforms have been detected in non-human mammalian tissues, expression and localization of eNOS in the normal and failing human myocardium are poorly defined. Therefore, the present study was designed to investigate eNOS in human cardiac tissues in the presence and absence of congestive heart failure (CHF).Normal and failing atrial tissue were obtained from six cardiac donors and six end-stage heart failure patients undergoing primary cardiac transplantation. ENOS protein expression and localization was investigated utilizing Western blot analysis and immunohistochemical staining with the polyclonal rabbit antibody to eNOS (Transduction Laboratories, Lexington, Kentucky).

Increased cardiac microvascular permeability and activation of cardiac endothelial nitric oxide synthase in high tidal volume ventilation-induced lung injury

2010 ◽  
Vol 4 (1) ◽  
pp. 27-36
Author(s):  
Ming-Jui Hung ◽  
Ming-Yow Hung ◽  
Wen-Jin Cherng ◽  
Li-Fu Li
Keyword(s):  
Nitric Oxide ◽  
Nitric Oxide Synthase ◽  
Lung Injury ◽  
Tidal Volume ◽  
Endothelial Nitric Oxide Synthase ◽  
Microvascular Permeability ◽  
Akt Phosphorylation ◽  
Enos Phosphorylation ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

Abstract Background: Positive pressure ventilation with large tidal volumes has been shown to cause lung injury via the serine/threonine kinase-protein kinase B (Akt) and endothelial nitric oxide synthase (eNOS)-pathways. However, the effects of high tidal volume (VT) ventilation on the heart are unclear. Objectives: Evaluate the effect of VT ventilation on the cardiac vascular permeability and intracellular Akt and eNOS signaling pathway. Methods: C57BL/6 and Akt knock-out (heterozygotes, +/−) mice were exposed to high VT (30 mL/kg) mechanical ventilation with room air for one and/or five hours. Results: High VT ventilation increased cardiac microvascular permeability and eNOS phosphorylation in a timedependent manner. Serum cardiac troponin I was increased after one hour of high VT ventilation. Cardiac Akt phosphorylation was accentuated after one hour and attenuated after five hours of high VT ventilation. Pharmacological inhibition of Akt with LY294002 and high VT ventilation of Akt+/− mice attenuated cardiac Akt phosphorylation, but not eNOS phosphorylation. Conclusion: High VT ventilation increased cardiac myocardial injury, microvascular permeability, and eNOS phosphorylation. Involvement of cardiac Akt in high VT ventilation was transient.

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