Dietary omega 3 fatty acids decrease intraocular pressure with age by increasing aqueous outflow.
OBJECTIVE
To determine whether there is an association between dietary omega-3 (omega-3) fatty acid intake, age, and intraocular pressure (IOP) caused by altered aqueous outflow.


METHODS
Sprague-Dawley rats were fed either omega-3-sufficient (omega-3(+)) or omega-3-deficient (omega-3(-)) diets from conception. The diets had 7% lipid content. The omega-3(+) diet contained safflower, flaxseed, and tuna oils (5.5:1.0:0.5), and the omega-3(-) diet contained safflower oil only. Intraocular pressure was measured at 5 to 40 weeks of age under light anesthesia (omega-3(+), n = 39; omega-3(-), n = 48). Aqueous outflow was determined at 45 weeks in a subgroup of animals (omega-3(+), n = 15; omega-3(-), n = 22) using pulsed infusion. Ciliary body tissues (n = 6 per group) were assayed for fatty acid content by thin-layer and gas-liquid chromatography in both diet groups.


RESULTS
Animals raised on omega-3(+) diets had a 13% decrease in IOP at 40 weeks of age (13.48 +/- 0.32 mm Hg vs. 15.46 +/- 0.29 mm Hg; P < 0.01). When considered as a change in IOP relative to 5 weeks of age, the omega-3(+) group showed a 23% decrease (P < 0.001). This lower IOP in the omega-3(+) diet group was associated with a significant increase (+56%; P < 0.001) in outflow facility and a decrease in ocular rigidity (-59%; P < 0.001). The omega-3(+) group showed a 3.3 times increase in ciliary body docosahexaenoic acid (P < 0.001).


CONCLUSIONS
Increasing dietary omega-3 reduces IOP with age because of increased outflow facility, likely resulting from an increase in docosanoids. This indicates that dietary manipulation may provide a modifiable factor for IOP regulation. However, further studies are needed to consider whether this can modify the risk for glaucoma and can play a role in treatment of the disease.
Nguyen
Christine T O
CT
Department of Optometry and Vision Sciences, University of Melbourne, Parkville, Victoria, Australia.
Bui
Bang V
BV
Sinclair
Andrew J
AJ
Vingrys
Algis J
AJ
D000375:Aging / Q000502:physiology*; D000818:Animals; D001082:Aqueous Humor / Q000378:metabolism*; D002849:Chromatography, Gas; D002855:Chromatography, Thin Layer; D002924:Ciliary Body / Q000737:chemistry; D004032:Diet; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage* / Q000032:analysis; D007429:Intraocular Pressure / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014065:Tonometry, Ocular
D015525:Fatty Acids, Omega-3