Does atorvastatin induce aortic smooth muscle cell apoptosis in vivo?
It has been reported that HMG-CoA reductase inhibitors such as atorvastatin induce vascular smooth muscle cell (SMC) apoptosis in vitro. However, this effect remains to be demonstrated in vivo. The present studies were designed to test the ability of atorvastatin to induce SMC apoptosis in vivo, using the spontaneously hypertensive rat (SHR) as a well-known reference model of SMC apoptosis induction in vivo by cardiovascular drugs including the calcium channel blocker amlodipine. Atorvastatin was administered to SHR for 3 or 6 weeks either alone or together with amlodipine, a drug combination clinically available to patients. Primary endpoints included aortic medial hypertrophy and aortic SMC hyperplasia, internucleosomal DNA fragmentation and expression of the apoptosis regulatory proteins Bax and Bcl-2. The SHR aorta showed no evidence of SMC apoptosis induction by atorvastatin, even at the high dose of 50 mg kg(-1) day(-1), although the statin significantly reduced oxidative stress after 3 weeks and blood pressure after 6 weeks of administration. Amlodipine-induced regression of aortic hypertophy and aortic SMC hyperplasia were dose- and time-dependent, but there was no interaction between atorvastatin and amlodipine in modulating the primary endpoints. These results do not support the notion that atorvastatin induces SMC apoptosis in the aortic media in vivo.
Faculty of Pharmacy, Université de Montréal, 2900 Édouard-Montpetit, Room 3201, P.O. Box 6128, Station Centre-Ville, Montréal, Québec, Canada, H3C 3J7. marielle.doyon@umontreal.ca
Marielle
M
Doyon
Taben Mary
TM
Hale
Julie-Emilie
JE
Huot-Marchand
Rong
R
Wu
Jacques
J
de Champlain
Denis
D
DeBlois
D017311:Amlodipine / Q000494:pharmacology; D000818:Animals; D001011:Aorta; D017209:Apoptosis / Q000187:drug effects*; D051017:Apoptosis Regulatory Proteins / Q000096:biosynthesis; D000069059:Atorvastatin; D001794:Blood Pressure / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000494:pharmacology; D053938:DNA Fragmentation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004359:Drug Therapy, Combination; D006538:Heptanoic Acids / Q000494:pharmacology*; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology*; D006973:Hypertension / Q000188:drug therapy; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects* / Q000503:physiopathology; D032389:Myocytes, Smooth Muscle / Q000187:drug effects*; D018384:Oxidative Stress / Q000187:drug effects; D011758:Pyrroles / Q000494:pharmacology*; D051381:Rats; D011918:Rats, Inbred SHR
D051017:Apoptosis Regulatory Proteins; D002121:Calcium Channel Blockers; D006538:Heptanoic Acids; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D011758:Pyrroles; D017311:Amlodipine; D000069059:Atorvastatin