Topical Omega-3 and Omega-6 Fatty Acids for Treatment of Dry Eye.

Key Findings:

A cross-sectional study of 32470 women showed a 68% lower prevalence of dry eye syndrome (DES) with higher n3 intakes. In this work, topical application of ALA resulted in a significant reversal in cornea epithelial damage, manifested by decreased fluorescein staining as compared with the untreated eyes and eyes treated with vehicle, LA, or combined ALA and LA. At the molecular level, dry eye induction leads to a persistent increase in corneal expression of the inflammatory biomarkers IL-1a and TNF-a. ALA treatment was effective in decreasing the corneal and conjunctival expression of inflammatory markers, IL-1a and TNF-a.  A nearly 100-fold increased expression of IL-10 in dry eye conjunctiva which was reduced by ALA.  ALA application showed a reduction in the corneal leukocyticin filtration which may be due to decreased cytokine expression, especially TNF-a.

ABSTRACT:

To study the efficacy of topical application of alpha-linolenic acid (ALA) and linoleic acid (LA) for dry eye treatment. Formulations containing ALA, LA, combined ALA and LA, or vehicle alone, were applied to dry eyes induced in mice. Corneal fluorescein staining and the number and maturation of corneal CD11b+cells were determined by a masked observer in the different treatment groups. Real-time polymerase chain reaction was used to quantify expression of inflammatory cytokines in the cornea and conjunctiva. Dry eye induction significantly increased corneal fluorescein staining; CD11b+cell number and major histocompatibility complex Class II expression; corneal IL-1alpha and tumor necrosis factor alpha (TNF-a) expression; and conjunctival IL-1alpha, TNF-alpha, interferon gamma, IL-2, IL-6, and IL-10 expression. Treatment with ALA significantly decreased corneal fluorescein staining compared with both vehicle and untreated controls. Additionally, ALA treatment was associated with a significant decrease in CD11b+ cell number, expression of corneal IL-1a and TNF-a, and conjunctival TNF-a. Topical ALA treatment led to a significant decrease in dry eye signs and inflammatory changes at both cellular and molecular levels. Topical application of ALA omega-3 fatty acid may be a novel therapy to treat the clinical signs and inflammatory changes accompanying dry eye syndrome. (Author’s abstract)