Reactive oxygen species (ROS) are released during the inflammation of the synovial membrane associated with cartilage degradation in osteoarthritis. In this work, we exposed synoviocytes to superoxide anions at concentrations that may cause either apoptosis or necrosis. We studied membrane organization, dehydrogenase mitochondrial activity and nuclear morphology and integrity, to determine the nature of the death process initiated by superoxide anions and tried to counteract ROS effects with alpha-tocopherol. We found that oxidative stress caused synoviocytes to undergo a process of cell death of an apoptotic nature rather than necrotic. Mitochondrial injury occurred at an early stage, and the FITC-annexin-V-positive/propidium iodide-positive cells occurred later than the metabolic changes. DNA strand breaks were evident at 8 h and nuclear condensation at 24 h. No LDH activity was detected in culture supernatants. In our experimental conditions, alpha-tocopherol had little effect on stress damage; the antioxidant properties of this molecule did not affect the apoptosis caused by superoxide anions.

Vitamins A and E were determined in the serum of 80 free-living healthy elderly subjects and in 80 healthy younger adults. Mean values and normal ranges were established for both groups and the influence of sex and age studied. We found a significantly lower level of vitamin A in the elderly men and women and a higher level of vitamin E in elderly women, relative to their younger counterparts. These differences may be related to life-style and age-associated physiological changes and justify the use of age-corrected standard values.

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Aspartate aminotransferase (ASAT) and alanine aminotransferase (ALAT) activity was measured in a group of 81 healthy subjects over 70 years of age and another of 180 younger persons, in order to investigate histograms and means of aminotransferase values in both groups and the variation in stimulation of these enzyme activities by pyridoxal 5'-phosphate (P5P) added in vitro. It was found that ASAT and ALAT mean values were significantly higher in both groups in the presence of P5P, than in the absence of P5P. ASAT and ALAT mean values obtained with and without P5P in old people were similar to those found in young subjects. In addition, mean stimulation percentages by P5P were identical in both groups.