We have previously reported that adenoviral-mediated delivery of
cytochrome P-450 (CYP) 4A2, which catalyzes the synthesis of
20-hydroxyeicosatetraenoic acid (20-HETE), results in endothelial dysfunction and
hypertension in Sprague-Dawley (SD) rats (Wang JS, Singh H, Zhang F, Ishizuka T, Deng H, Kemp R, Wolin MS, Hintze TH, Abraham NG, Nasjletti A, Laniado-Schwartzman M. Circ Res 98: 962-969, 2006). In this study, we targeted the vascular endothelium by using a lentivirus construct expressing
CYP4A2 under the control of the endothelium-specific promoter
VE-cadherin (VECAD-4A2) and examined the effect of long-term
CYP4A2 overexpression on blood pressure and kidney function in SD rats. A bolus injection of VECAD-4A2 increased blood pressure (P < 0.001) by 26, 36, and 30 mmHg 10, 20, and 30 days postinjection, respectively. Arteries from VECAD-4A2-transduced rats produced increased levels of
20-HETE (P < 0.01), expressed lower levels of
endothelial nitric oxide synthase (eNOS) and phosphorylated eNOS (p-eNOS) (P < 0.05), generated higher levels of
superoxide anion, and displayed decreased relaxing responsiveness to
acetylcholine (P < 0.05).
Proteinuria increased by twofold in VECAD-4A2-transduced rats compared with controls. Treatment of VECAD-4A2-transduced rats with
HET0016, an inhibitor of
20-HETE biosynthesis, not only attenuated the increase in blood pressure (P < 0.05) but also improved vascular function (
acetylcholine-induced relaxations) and reduced plasma
creatinine and
proteinuria.
HET0016 treatment decreased oxidative stress and increased the phosphorylated state of key
proteins that regulate endothelial function, including eNOS, AKT, and AMPK. Collectively, these findings demonstrate that augmentation of vascular endothelial
20-HETE levels results in
hypertension, endothelial dysfunction, and renal injury, which is offset by
HET0016 through a reduction in vascular
20-HETE coupled with a lessening of oxidative stress and the amplification of pAKT, pAMPK, and p-eNOS levels leading to normalization of endothelial responses.