Zofenopril inhibits the expression of adhesion molecules on endothelial cells by reducing reactive oxygen species.

Hypertension and coronary artery disease are intimately connected. The migration of circulating monocytes into the subendothelial occurs through the expression of some adhesion molecules on endothelial cells. The nuclear factor (NF)-kappaB, a redox-sensitive element, plays a key role in adhesion molecule gene induction. In this study we have compared the effects of two different angiotensin converting enzyme (ACE) inhibitors, one possessing an active sulfhydryl group (zofenopril) and one lacking this group (enalapril) on the cellular redox state (monitored by measuring intracellular reactive oxygen species and thiol status), expression of adhesion molecules, and activation of NF-kappaB in human umbilical vein endothelial cells (HUVECs). Zofenoprilat, the active form of zofenopril, significantly and dose dependently reduced the intracellular reactive oxygen species (ROS) and superoxide formation induced by oxidized low-density lipoprotein (ox-LDL) (P <.001) and tumor necrosis factor-alpha (TNF-alpha) (P <.001). Enalaprilat, the active form of enalapril, was ineffective. Zofenoprilat but not enalaprilat also decreased the consumption of the intracellular GSH induced by ox-LDL (P <.01) and TNF-alpha (P <.01). Although zofenoprilat significantly and dose dependently reduced the expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular cell adhesion molecule-1 (ICAM-1), and E-selectin induced by ox-LDL (P <.01) and TNF-alpha (P <.01) on HUVECs, enalaprilat did not. Ox-LDL and TNF-alpha increased the activation of NF-kappaB and the preincubation of HUVECs with zofenoprilat, but not with enalaprilat, dose dependently reduced its activation (P <.001). The conclusion is that the sulfhydryl (SH)-containing ACE inhibitors may be useful in inhibiting foam cell formation and thus slow the development of atherosclerosis.

Quantitative analysis of bile acids in human plasma by liquid chromatography-electrospray tandem mass spectrometry: a simple and rapid one-step method.

Bile acids play a pivotal role in the metabolism of cholesterol and lipids. Their blood concentrations are important prognostic and diagnostic indicators of hepatobiliary and intestinal dysfunction. This class of molecules comprises a heterogeneous group of compounds with a common cholesterol scaffold. Recently, the introduction of liquid chromatography coupled to tandem mass spectrometry methods has revealed an innovative path in the quantisation of specific bile acids in biological specimens. A robust and sensitive method has been developed based on high performance liquid chromatography separation coupled to an electrospray triple-quadrupole mass spectrometer. Human plasma samples were analysed on a C18 reverse-phase column. The elution profiles were monitored in multiple reaction-monitoring mode, quantifying and identifying each analyte by its own unique precursor to product patterns. A linear correlation over a broad range of bile acid concentrations (0.1-100 microM) was observed. The average recovery period for all of the analysed bile acids was 98 +/- 3%. Intra-day and inter-day precision averages were 2% and 5.4%, respectively. The determination was achieved within a single chromatographic run for all unconjugated, glycine- and taurine-conjugated isomeric forms of bile acids. As a proof of principle this method has been validated on a small subset of cholestatic patients (n = 7) and compared to appropriate clinical controls (n = 10). Based upon our encouraging experimental results, the described HPLC separation coupled to tandem mass spectrometry method for the analysis of bile acids in biological samples is deemed a robust and accurate procedure. Consequently, we propose this technique as a suitable candidate method for the identification and quantitation of bile acids in routine analysis.