Effects of dietary vitamin E supplementation on pulmonary morphology and collagen deposition in amiodarone- and vehicle-treated hamsters

Amiodarone (AM) is a potent antidysrhythmic agent that is limited in clinic al use by its adverse effects, including potentially life-threatening AM-in duced pulmonary toxicity (AIPT). The present study tested the ability of di etary supplementation with vitamin E (500 IU d,1-alpha-tocopherol acetate/k g chow) to protect against pulmonary damage following intratracheal adminis tration of AM (1.83 mu mol) to the male golden Syrian hamster. At 21 days p ost-dosing, animals treated with AM had increased lung hydroxyproline conte nt and histological disease index values compared to control (P < 0.05), wh ich were indicative of fibrosis. Dietary vitamin E supplementation for 6 we eks resulted in a 234% increase in lung vitamin E content at the time of AM dosing, and maintenance on the diet prevented AM-induced elevation of hydr oxyproline content and disease index 21 days post-dosing. Dietary vitamin E supplementation also decreased hydroxyproline content and disease index va lues in hamsters treated intratracheally with distilled water, the AM vehic le. These results demonstrate a protective role for vitamin E in an in vivo model of AIPT, and suggest that this antioxidant may have non-specific ant ifibrotic effects in the lung. (C) 1999 Elsevier Science Ireland Ltd. All r ights reserved.