Low concentrations of cis-linoleic acid induce cell damage in epithelial cells from bovine lenses

As low as 5 micromol/l of cis-linoleic acid proves to be cytotoxic for bovine lens epithelial cells in culture. Albumin eliminates the linoleic acid cytotoxicity completely, presumably by binding the fatty acid. However, the damaging effect appears again when the molar ratio of linoleic acid to albumin exceeds 1:1. The assumption that the linoleic acid-caused cell damage would be mediated by peroxidation products could not be confirmed. The results obtained rather favor the idea that linoleic acid molecules themselves injure lens epithelial cells. Obviously, cell damage even occurs in the presence of albumin if one molecule of albumin binds more than one molecule of linoleic acid. Micromolar concentrations of linoleic acid produce reversible bleb formation as well as cell retraction within 30 min. In primary culture 10 micromol/l linoleic acid damage lens epithelial cells irreversibly within some hours. Trans-linoleic acid, linolenic acid and oleic acid are also harmful to lens cells but to a lesser degree, while saturated fatty acids are without any effect. Bleb formation as a leading early sign hints at the plasma membrane as the primary target for linoleic acid induced cytotoxicity.