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Updated: Jun 8, 2026
08:58
En Face Detection of Nitric Oxide and Superoxide in Endothelial Layer of Intact Arteries
Published on: February 25, 2016
NA+/H+ exchanger 1- and aquaporin-1-dependent hyperosmolarity changes decrease nitric oxide production and induce
R Madonna1, E Montebello, G Lazzerini
1Cardiology and Center of Excellence on Aging, G. d'Annunzio University, Chieti, Italy.
International Journal of Immunopathology and Pharmacology
|October 15, 2010
Summary
High glucose in diabetes causes hyperosmolarity, leading to inflammation in blood vessels. This study reveals that targeting osmosignaling pathways, involving AQP1 and NHE-1, can reduce these harmful effects.
Area of Science:
- Endocrinology
- Cell Biology
- Vascular Biology
Background:
- Diabetic hyperglycemia induces hyperosmolarity, contributing to endothelial dysfunction.
- Understanding the mechanisms of hyperglycemia-induced endothelial inflammation is crucial for developing targeted therapies.
Purpose of the Study:
- To investigate the role of hyperosmolarity in the pro-inflammatory effects of hyperglycemia on endothelial cells.
- To elucidate the specific molecular mechanisms, including aquaporin-1 (AQP1) and Na+/H+ exchanger 1 (NHE-1) pathways, involved in these effects.
Main Methods:
- Human aortic endothelial cells (HAEC) were exposed to high glucose (HG) or hyperosmolar mannitol (HM) with or without inhibitors of AQP1, NHE-1, and protein kinase C (PKC).
- Key markers assessed included phosphorylated endothelial nitric oxide synthase (Ser1146-eNOS), vascular cell adhesion molecule-1 (VCAM-1) expression, and nitrite production.
- Gene silencing of AQP1 was also employed to confirm its role.
Main Results:
- Both HG and HM treatments decreased Ser1146-eNOS expression and increased VCAM-1 expression, indicating endothelial inflammation.
- AQP1 expression was significantly enhanced by HG/HM exposure.
- Inhibitors of AQP1 (DMSO), NHE-1 (cariporide), and PKC (calphostin C, LY379196) attenuated HG/HM-induced VCAM-1 expression and restored eNOS activation and nitrite production.
Conclusions:
- Hyperglycemia-induced endothelial inflammation in HAEC is mediated by hyperosmolarity.
- The water channels AQP1 and NHE-1, along with a PKCbeta signaling pathway, are key players in this osmosignaling cascade.
- Targeting these osmosignaling pathways presents a potential novel therapeutic strategy to mitigate the vascular complications of hyperglycemia.
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