Butyrylcholinesterase activity in women with diabetes mellitus in pregnancy: correlation with antioxidant activity.

A total of: 25 women with gestational diabetes, 25 with type 2 diabetes, 21 with healthy pregnancies and 15 non-pregnant healthy controls were investigated to evaluate the relationship between butyrylcholinesterase activity and antioxidant status in the serum and placenta of diabetic pregnant women. Levels of antioxidant activities were estimated by Randox Kits and malondialdehyde and butyrylcholinesterase by colorimetric methods. Butyrylcholinesterase activity was elevated in the serum and placenta in normal pregnancy vs diabetic cohorts (p < 0.01) and there was a higher activity level in gestational and type 2 diabetes on insulin (p < 0.05) compared with diet controlled. There was higher malondialdehyde and lower antioxidant activity in diet vs insulin controlled diabetes (p < 0.01). Serum and placental butyrylcholinesterase activity showed a strong inverse correlation with malondialdehyde (r = -0.876, p < 0.001) and (r = 0.542, p < 0.01), but strong positive correlation with total antioxidant activity in serum (r = 0.764, p < 0.001) and placenta (r = 0.642, p < 0.01). Butyrylcholinesterase may therefore, be involved in reducing oxidative stress in diabetic pregnancy.

Factors contributing to gender differences in serum retinol and alpha-tocopherol in infertile couples.

Oxidative stress is detrimental to fertility potential. Retinol and alpha-tocopherol are natural antioxidants that inhibit lipid peroxidation and protect against cell damage induced by oxidative stress. This study evaluated whether gender-related differences in antioxidant status exist among couples with infertility and, if so, to evaluate relevant factors that may contribute to such differences. Retinol and alpha-tocopherol in the sera of 40 couples and in the semen of 40 men were measured using high performance liquid chromatography. Serum retinol and alpha-tocopherol in women were significantly higher than in men (both P < 0.001). There was an inverse relationship between body mass index and serum retinol and alpha-tocopherol in both men and women. Heavy smokers (>or=20 cigarettes/day), compared with nonsmokers, had lower serum concentrations of retinol and alpha-tocopherol. Serum concentrations of retinol and alpha-tocopherol in men with normal sperm parameters were significantly higher than in those with oligozoospermia and asthenozoospermia (both P < 0.001). Lower serum retinol and alpha-tocopherol in men compared with their female partners could be related to their older age, higher body mass index and smoking habits. Low concentrations of these natural antioxidants were associated with abnormal semen parameters in men and anovulation in women.

Indications of the mechanisms involved in improved sperm parameters by zinc therapy.

OBJECTIVE: To determine possible indications of the mechanisms involved in improved sperm parameters by zinc therapy in asthenozoospermic men. SUBJECTS AND METHODS: Forty-five men with asthenozoospermia (>or=40% immotile sperm) were randomized into four therapy groups: zinc only: n = 11; zinc + vitamin E: n = 12 and zinc + vitamins E + C: n = 14 for 3 months, and non-therapy control group: n = 8. Semen analysis was done according to WHO guidelines. Malone dialdehyde, tumour necrosis factor-alpha (TNF-alpha), total antioxidant capacity, superoxide dismutase (SOD) and glutathione peroxidase were determined in the semen and serum. Antisperm antibodies IgG, IgM and IgA were evaluated by immunobeads. Sperm chromatin integrity was determined by acid denaturation by acridine orange and sperm apoptosis by light and electron microscopy. The effect of zinc on in vitro induced sperm oxidative stress by NADH was evaluated. RESULTS: Asthenozoospermia was significantly associated with oxidative stress with higher seminal malone dialdehyde (8.8 vs. 1.8 mmol/l, p < 0.001) and TNF-alpha (60 vs. 12 pg/l, p < 0.001), and low total antioxidant capacity (1.8 vs. 8.4, p < 0.01), SOD (0.8 vs. 3.1, p < 0.01) and glutathione peroxidase (1.6 vs. 4.2, p < 0.05), compared to normozoospermia. Zinc therapy alone, in combination with vitamin E or with vitamin E + C were associated with comparably improved sperm parameters with less oxidative stress, sperm apoptosis and sperm DNA fragmentation index (DFI). On the whole, there was no difference in the outcome measures between zinc only and zinc with vitamin E and combination of vitamins E + C. In the in vitro experiment zinc supplementation resulted in significantly lower DFI (14-29%, p < 0.05) compared to zinc deficiency. CONCLUSION: Zinc therapy reduces asthenozoospermia through several mechanisms such as prevention of oxidative stress, apoptosis and sperm DNA fragmentation.

Effect of increased glucose load on maternal-fetal transport of alpha-aminoisobutyric acid in the perfused human placenta: in vitro study.

The role of hyperglycemia on modulation of maternal-fetal transport of amino acids in humans is little understood. Hence, we have explored the effect of increased glucose load on transport kinetics of a model non-metabolizable amino acid, alpha-aminoisobutyric acid (AIB), in the human placenta in vitro. Transport kinetics of AIB in maternal-fetal direction was studied using perfusion of isolated human placental lobules. NCTC (National Culture and Tissue Collection)-135 medium, diluted with Earle's buffered salt solution was used as the perfusate and tritiated water was used as the reference marker. Effect of increased glucose load on transport kinetics of study and reference substances was studied in normal term placentae (n=5; gestational age, 38.5 +/- 0.5 weeks) in succeeding experimental phases, after a control perfusion phase with physiological glucose concentration. AIB transport fraction (TF), relative to tritiated water TF, averaged 54.8% in control euglycemic phase while in hyperglycemic concentration phases of 27.8 and 55.6 mM, the AIB TF index averaged 42.4% and 38.2%, respectively. Analysis of variance revealed that the difference was statistically significant. Similarly, absorption rate index of the amino acid was also significantly lower in the hyperglycemic perfusion phases compared to control euglycemic phase. We conclude that hyperglycemia may play a deleterious role in limiting maternal-fetal transport of A-type amino acids in the in vivo state.