Copper-zinc Superoxide dismutase (Cu,Zn-superoxide dismutase) activity was evaluated in lymphocytes and polymorphonuclear cells of insulin-dependent (n = 33) and non-insulin-dependent (n = 34) diabetic patients. A commercial method for the measurement of Superoxide dismutase activity was adapted for use on a discrete analyser and evaluated for interference by other antioxidants with Superoxide anion-scavenging properties. In comparison to healthy control subjects (n = 32), a significantly lower Cu,Zn-superoxide dismutase activity was found in both lymphocytes and polymorphonuclear cells of insulin-dependent (2.08 ± 0.58 vs. 1.70 ± 0.46 U/mg protein, p < 0.05, and 1.06 ± 0.46 vs. 0.64 ± 0.40 U/mg protein, p < 0.001, respectively) and non-insulin-dependent diabetic patients (2.08 ± 0.58 vs. 1.61 ± 0.48 U/mg protein, p < 0.01, and 1.06 ± 0.46 vs. 0.53 ± 0.24 U/mg protein, p < 0.001, respectively). There was a weak, but significant negative correlation between age and Cu,Zn-superoxide dismutase activity in lymphocytes and polymorphonuclear cells (r = -0.22 and r = -0.28, p < 0.05, respectively), whereas no influence of gender, diabetes duration and glycaemic control was observed. The results indicate that diabetes mellitus could elicit a significant disturbance in Superoxide anion-scavenging potential of lymphocytes and polymorphonuclear cells.

This study has investigated the antioxidant capacity of human seminal plasma due to the presence of both high and low molecular weight antioxidant factors. Methods for the measurement of superoxide dismutase-like activity (SOD-like) and total antioxidant status (TAS) were automated, and had a within-run coefficient of variation of 7.3% for SOD-like activity and 4.8% for TAS. In 69 semen samples from unselected infertile men, SOD-like activity in seminal plasma ranged from 2 to 16 U/ml, with a mean of 6.9 +/- 2.8 U/ml. As SOD-like activity was correlated positively with levels of citric acid (p < 0.0001), zinc (p < 0.0002) and acid phosphatase activity (p < 0.0005), and there was no correlation with fructose levels, our results suggest that prostatic secretions are an important source of superoxide anion scavengers. Evaluation of SOD-like activity in infertile men with accessory sex gland infections (n = 12) showed significantly lower activity (p < 0.003) compared to values found in 12 infertile men without signs of infection. The values obtained for total antioxidant status (equivalent to the antioxidant capacity of alpha-tocopherol analogue) ranged from 1.7 to 2.3 mmol/L, with a mean of 2.1 +/- 0.1 (n = 40), reflecting the protective activity of ascorbate, urate and albumin, and to a very low extent of glutathione and taurine. The data obtained by TAS assay correlated with fructose, a major marker of vesicular secretion (p < 0.005), suggesting that low molecular weight components with antioxidant capacity derive partly from the seminal vesicles. The results indicate that the relative contribution of antioxidant defence systems capable of counteracting the deleterious action of superoxide anions, depends on the secretory activity of accessory sex glands and is independent of excessive ROS production due to increased oxidative stress.

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Key words. Spermatozoa induced lipid peroxidationsuperoxide dismutase-like activityisoenzyme LDH-C4 -diaphoraseexperimentally I Summary. Superoxide dismutase-like activity (SOD-like), isoenzyme lactate dehydrogenase-C4 (LDH-C4) and NADH-diaphorase activities in spermatozoa have been investigated from 58 normozoospermic and 27 oligozoospermic men.Significantly higher SOD-like, LDH-C4 and diaphorase activities (P

The ascorbate/urate ratio in the seminal plasma was studied in 76 randomly chosen infertile men. The levels of ascorbate and urate were found to vary widely (range: 93-954 pmol 1-' and 127-670 pmol 1-', respectively), while the ascorbate/urate ratio was 1.03 f 0.63 (mean & SD), indicating almost equimolar concentrations of both compounds in more than 60% of the subjects investigated. No relationship of ascorbate with any biochemical marker of accessory sex gland secretions was observed, whereas an inverse correlation of urate with some prostatic markers, acid phosphatase (-0.37; P