Premium
Effect of Nitric Oxide Synthase and growth conditions on hydrogen peroxide production in cultured endothelial cells during shear stress
Author(s) -
Zinkevich Natalya S,
Gutterman David D
Publication year - 2010
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.24.1_supplement.602.6
Subject(s) - nitric oxide , hydrogen peroxide , nitric oxide synthase , chemistry , medicine , reactive oxygen species , endocrinology , flow cytometry , dichlorofluorescein , microbiology and biotechnology , catalase , omega n methylarginine , andrology , biology , biochemistry , oxidative stress
Endothelial cells release nitric oxide (NO) and reactive oxygen species (ROS) during acute shear stress (SS). We hypothesized that chronic SS attenuates the production of H 2 O 2 during acute SS. Human microvascular endothelial cells (HMVEC) were exposed to one hour of laminar SS, either with or without a preceding 24 hour SS exposure (chronic SS). Cells were studied either in full serum media (5%) or after serum‐starving (to increase ROS) overnight (0.5% serum). 2′,7′‐dichlorofluorescein (DCF) assessed H 2 O 2 formation with flow cytometry (N=3–7). Acute SS increased H 2 O 2 release compare to static conditions (4.4±0.5 fold increase (F.I.) for 0.5% serum and 1.7±0.2 F.I for 5% serum (p<0.05)). Presence of L‐Nitro‐Arginine Methyl Ester (L‐NAME; nitric oxide synthase inhibitor) during acute shear reduced production of H 2 O 2 in serum starved cells (2.7±0.2 F.I. vs. 4.4±0.5 F.I. (p<0.05)), but not in full serum. Acute SS after chronic SS reduced H 2 O 2 in cells grown in low (1.9±0.8 F.I.) and full serum (0.9±0.1 F.I.). This reduction in H 2 O 2 was reversed by L‐NAME in full serum (2.2±0.5 F.I. vs. 0.9±0.1 F.I. (p<0.05)), but not in low serum. Preconditioning with 24 hrs of SS inhibits generation of H 2 O 2 during acute SS. We conclude that NOS modulates H 2 O 2 production differentially in high and low serum conditions.