Dietary docosahexaenoic acid protects against N-methyl-N-nitrosourea-induced retinal degeneration in rats.
The effect of dietary intake of specific types of fatty acids on retinal degeneration due to N-methyl-N-nitrosourea (MNU)-induced photoreceptor cell apoptosis was evaluated. Fifty-day-old female Sprague-Dawley rats were given a single intraperitoneal injection of 50 mg kg(-1) body weight of MNU, and were then switched to one of five different diets containing the following fatty acids at the following weight percentages: 10% linoleic acid (LA); 9.5% palmitic acid (PA) and 0.5% LA; 9.5% eicosapentaenoic acid (EPA) and 0.5% LA; 4.75% EPA, 4.75% docosahexaenoic acid (DHA) and 0.5% LA; or 9.5% DHA and 0.5% LA. When rats developed MNU-induced mammary tumors with a diameter of > or =1 cm, or at the termination of the experiment (20 weeks after MNU injection), retinal tissue samples were obtained and examined. Incidence and severity of retinal damage were compared by histologic examination. MNU-induced retinal degeneration was prevented in rats fed the diet containing 9.5% DHA (4.75% DHA was less effective), whereas it was accelerated in rats fed the 10% LA diet. Over the course of the 20-week experimental period, the fatty acid composition of serum reflected differences in dietary fatty acids. The present results indicate that a diet containing 9.5% DHA can counteract MNU retinotoxicity in the rat retina. DHA may play a role in protection against MNU-induced photoreceptor cell apoptosis in the rat retina.
Moriguchi
Kaei
K
Department of Pathology II, Kansai Medical University, Moriguchi, Osaka 570-8506, Japan.
Yuri
Takashi
T
Yoshizawa
Katsuhiko
K
Kiuchi
Katsuji
K
Takada
Hideho
H
Inoue
Yoshikazu
Y
Hada
Takahiko
T
Matsumura
Miyo
M
Tsubura
Airo
A
D000477:Alkylating Agents / Q000633:toxicity*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002470:Cell Survival; D004281:Docosahexaenoic Acids / Q000008:administration & dosage*; D005260:Female; D015674:Mammary Neoplasms, Animal / Q000139:chemically induced / Q000473:pathology; D008770:Methylnitrosourea / Q000633:toxicity*; D020419:Photoreceptor Cells, Vertebrate / Q000166:cytology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012162:Retinal Degeneration / Q000139:chemically induced / Q000178:diet therapy / Q000517:prevention & control*
D000477:Alkylating Agents; D004281:Docosahexaenoic Acids; D008770:Methylnitrosourea