MODELING CORTICAL CATARACTOGENESIS - XX - IN-VITRO EFFECT OF ALPHA-LIPOIC ACID ON GLUTATHIONE CONCENTRATIONS IN LENS IN MODEL DIABETIC CATARACTOGENESIS

In previous studies stereospecific protection against lens opacity was consistent with specific reduction of R-alpha-lipoic acid(R-alpha-LA) in mitochondria of the vulnerable cells at the lens equator where the first globular degeneration is seen in glucose cataract. In this stud y two further possible explanations of this effect were investigated: (1) increased glucose uptake by the lens, leading to increased glycoly sis and release of lactate into the incubation medium and/or (2) maint enance of glutathione levels by the R-alpha-LA. The data did not suppo rt 1, but was consistent with 2, after 24 hr incubation. The concentra tions of glutathione in normal lenses or lenses incubated with R- or r acemic alpha-LA were not significantly different, but the concentratio n of glutathione in lenses incubated with S-alpha-LA was significantly lower than the R-alpha-LA-incubated lenses.