Dietary omega-3 fatty acid deficiency and visual loss in infant rhesus monkeys.

TLDR

Linolenic acid is a dietary precursor of DHA, the major fatty acid in retinal photoreceptor membranes. The study hypothesized that prenatal and postnatal omega‑3 deprivation in rhesus monkeys would deplete plasma omega‑3s and impair vision. Adult female rhesus monkeys were fed low‑omega‑3 diets during pregnancy and their infants from birth, while a control group received adequate linolenic acid. Infants on the deficient diet showed progressive depletion of DHA in plasma phospholipids, reaching 6 % of control by 12 weeks, and their visual acuity was reduced by 25 % at 4 weeks and 50 % at 8 and 12 weeks compared with controls.

Abstract

Linolenic acid (18:3 omega 3) is a dietary precursor of docosahexaenoic acid (22:6 omega 3), the major fatty acid in the photoreceptor membranes of the retina. We hypothesized that rhesus monkeys deprived of dietary omega-3 fatty acids during prenatal and postnatal development would show plasma depletion of these fatty acids and visual impairment. Semipurified diets low in omega-3 fatty acids were fed to one group of adult female rhesus monkeys throughout pregnancy and to their infants from birth. A control group of mothers and infants received similar diets but supplying ample linolenic acid. In the plasma phospholipids of deficient infants, linolenic acid was generally undetectable and 22:6 omega 3 levels became progressively depleted, falling from 42% of control values at birth to 21% at 4 wk, 9% at 8 wk, and 6% at 12 wk of age. In the other plasma lipid classes, 22:6 omega 3 was undetectable by 12 wk. The visual acuity of the deprived infants, as measured by the preferential looking method, was reduced by one-fourth at 4 wk (P less than 0.05) and by one-half at 8 and 12 wk (P less than 0.0005) compared with control infants. These results suggest that omega-3 fatty acids may be an essential nutrient, and that 22:6 omega 3 may have a specific function in the photoreceptor membranes of the retina.