Article

Atorvastatin and fenofibrate have comparable effects on VLDL-apolipoprotein C-III kinetics in men with the metabolic syndrome.

Metabolic Research Centre, School of Medicine and Pharmacology, University of Western Australia, Perth, Australia.
Arteriosclerosis Thrombosis and Vascular Biology (impact factor: 6.37). 06/2008; 28(10):1831-7. DOI:10.1161/ATVBAHA.108.170530
Source: PubMed

ABSTRACT The metabolic syndrome (MetS) is characterized by insulin resistance and dyslipidemia that may accelerate atherosclerosis. Disturbed apolipoprotein (apo) C-III metabolism may account for dyslipidemia in these subjects. Atorvastatin and fenofibrate decrease plasma apoC-III, but the underlying mechanisms are not fully understood.
The effects of atorvastatin (40 mg/d) and fenofibrate (200 mg/d) on the kinetics of very-low density lipoprotein (VLDL)-apoC-III were investigated in a crossover trial of 11 MetS men. VLDL-apoC-III kinetics were studied, after intravenous d(3)-leucine administration using gas chromatography-mass spectrometry and compartmental modeling. Compared with placebo, both atorvastatin and fenofibrate significantly decreased (P<0.001) plasma concentrations of triglyceride, apoB, apoB-48, and total apoC-III. Atorvastatin, not fenofibrate, significantly decreased plasma apoA-V concentrations (P<0.05). Both agents significantly increased the fractional catabolic rate (+32% and +30%, respectively) and reduced the production rate of VLDL-apoC-III (-20% and -24%, respectively), accounting for a significant reduction in VLDL-apoC-III concentrations (-41% and -39%, respectively). Total plasma apoC-III production rates were not significantly altered by the 2 agents. Neither treatment altered insulin resistance and body weight.
Both atorvastatin and fenofibrate have dual regulatory effects on VLDL-apoC-III kinetics in MetS; reduced production and increased fractional catabolism of VLDL-apoC-III may explain the triglyceride-lowering effect of these agents.

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Keywords

11 MetS men
 
2 agents
 
apoB
 
compartmental modeling
 
crossover trial
 
Disturbed apolipoprotein
 
fenofibrate decrease plasma apoC-III
 
fractional catabolic rate
 
gas chromatography-mass spectrometry
 
intravenous d(3)-leucine administration
 
metabolic syndrome
 
plasma apoA-V concentrations
 
total apoC-III
 
Total plasma apoC-III production rates
 
underlying mechanisms
 
very-low density lipoprotein
 
VLDL)-apoC-III
 
VLDL-apoC-III
 
VLDL-apoC-III concentrations
 
VLDL-apoC-III kinetics