1.
Different galenic formulations of fluvastatin have equal lipid-lowering potential but differ in reducing lipemia-induced endothelial dysfunction.
Westphal, S, Abletshauser, C, Luley, C
Coronary artery disease. 2009;(1):81-5
Abstract
BACKGROUND Postprandial lipemia is known to exert a reversible detrimental effect on endothelium-dependent flow-mediated vasodilation (FMD). Fasting FMD has shown to be improved by fluvastatin. In this study, we investigated whether lipemia-induced endothelial dysfunction can be mitigated by fluvastatin in two (immediate-release and extended-release) formulations. METHODS In 27 patients with the metabolic syndrome, randomized in a three-period crossover design for 5 weeks each to 80 mg extended-release fluvastatin daily, 40 mg immediate-release fluvastatin twice daily (b.i.d.) or placebo, the fasting and postprandial lipids and FMD of the brachial artery were measured at baseline and after 5 weeks of each treatment period. Postprandial lipemia was induced by administration of whipping cream containing 33% fat (1 g fat/kg body weight). FMD was determined by two-dimensional ultrasonography of the brachial artery in the fasting state and 4 h after the fatty meal. Lipids were determined using routine methods. RESULTS Fasting triglycerides were reduced after immediate-release and extended-release fluvastatin by 16 and 23%, respectively, and postprandial triglycerides by 20 and 29%, respectively. The fasting FMD was also improved by each treatment. The postprandial FMD impairment, however, was mitigated only after 40 mg b.i.d. After 80 mg fluvastatin, the last dose of which had been administered the previous evening, the lipemic FMD impairment was the same as after the placebo. CONCLUSION Fluvastatin improves fasting FMD regardless of whether it is administered as 40 mg b.i.d. or 80 mg daily given in the evening. The lipemic FMD impairment, in contrast, is improved only by 40 mg b.i.d. when the tablet is taken in the morning of the test day. As the half-life of fluvastatin is about 2 h, we surmise that an improvement occurs only when sufficient amounts of fluvastatin are present in the bloodstream.
2.
Chlorthalidone improves endothelial-mediated vascular responses in hypertension complicated by nondiabetic metabolic syndrome.
Dell'Omo, G, Penno, G, Del Prato, S, Pedrinelli, R
Journal of cardiovascular pharmacology and therapeutics. 2005;(4):265-72
Abstract
BACKGROUND The study was conducted to evaluate the vascular effects of chlorthalidone, a distal tubule-acting natriuretic agent, in hypertensive patients with nondiabetic metabolic syndrome, an insulin-resistant condition characterized by endothelial dysfunction and high risk for diabetes mellitus development. METHODS Thirteen untreated hypertensive patients with Adult Treatment Panel-III-defined nondiabetic metabolic syndrome were assigned to 3-month treatment with chlorthalidone. The end-points were baseline and post-treatment evaluation of (1) forearm blood flow (strain-gauge plethysmography) responses to graded intra-arterial acetylcholine infusion to test endothelial-mediated vasomotor function, with sodium nitroprusside as a control for endothelium-independent vasodilatation; (2) minimum forearm vascular resistance, the ratio of mean blood pressure and maximal blood flow in response to 13-minute arterial occlusion, as a hemodynamic correlate of arteriolar structure; and (3) transcapillary albumin escape rate (the 1-hour decay rate of (125)I-albumin, 6-8 microC ev) as a measure of systemic capillary permeability. Additional measurements included baseline and posttreatment lipids, fasting, and postload glucose and insulin as well as the homeostasis model assessment, an index of insulin sensitivity. RESULTS Chlorthalidone reduced blood pressure, augmented acetylcholine-mediated vasodilatation, decreased minimum forearm resistance, and slowed the transcapillary albumin escape rate. Metabolic parameters did not change significantly except for an increase in low-density lipoprotein cholesterol levels. CONCLUSIONS Chlorthalidone improved endothelial function, reversed abnormal arteriolar structure, and slowed albumin permeation in hypertensive patients with nondiabetic metabolic syndrome.