PLoS ONE (Jan 2014)

Add-on effect of probucol in atherosclerotic, cholesterol-fed rabbits treated with atorvastatin.

  • Yuka Keyamura,
  • Chifumi Nagano,
  • Masayuki Kohashi,
  • Manabu Niimi,
  • Masanori Nozako,
  • Takashi Koyama,
  • Reiko Yasufuku,
  • Ayako Imaizumi,
  • Hiroyuki Itabe,
  • Tomohiro Yoshikawa

DOI
https://doi.org/10.1371/journal.pone.0096929
Journal volume & issue
Vol. 9, no. 5
p. e96929

Abstract

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OBJECTIVE: Lowering the blood concentration of low-density lipoprotein (LDL) cholesterol is the primary strategy employed in treating atherosclerotic disorders; however, most commonly prescribed statins prevent cardiovascular events in just 30% to 40% of treated patients. Therefore, additional treatment is required for patients in whom statins have been ineffective. In this study of atherosclerosis in rabbits, we examined the effect of probucol, a lipid-lowering drug with potent antioxidative effects, added to treatment with atorvastatin. METHODS AND RESULTS: Atherosclerosis was induced by feeding rabbits chow containing 0.5% cholesterol for 8 weeks. Probucol 0.1%, atorvastatin 0.001%, and atorvastatin 0.003% were administered solely or in combination for 6 weeks, beginning 2 weeks after the start of atherosclerosis induction. Atorvastatin decreased the plasma concentration of non-high-density lipoprotein cholesterol (non-HDLC) dose-dependently; atorvastatin 0.003% decreased the plasma concentration of non-HDLC by 25% and the area of atherosclerotic lesions by 21%. Probucol decreased the plasma concentration of non-HDLC to the same extent as atorvastatin (i.e., by 22%) and the area of atherosclerotic lesions by 41%. Probucol with 0.003% atorvastatin decreased the plasma concentration of non-HDLC by 38% and the area of atherosclerotic lesions by 61%. Co-administration of probucol with atorvastatin did not affect the antioxidative effects of probucol, which were not evident on treatment with atorvastatin alone, such as prevention of in vitro LDL-oxidation, increase in paraoxonase-1 activity of HDL, and decreases in plasma and plaque levels of oxidized-LDL in vivo. CONCLUSIONS: Probucol has significant add-on anti-atherosclerotic effects when combined with atorvastatin treatment; suggesting that this combination might be beneficial for treatment of atherosclerosis.