Taitzoglou I A, Tsantarliotou M, Zervos I, Kouretas D, Kokolis N A
Department of Physiology, Faculty of Veterinary Medicine, University of Thessaly, 431 00 Karditsa, Greece.
Reproduction. 2001 Jan;121(1):131-7.
The effect of tannic acid, a common flavonoid, on the acrosin and plasminogen activator activity and plasmin activity of human and ram spermatozoa was evaluated. Acrosin and plasminogen activator activity were determined by spectrophotometry using the chromogenic substrates N-alpha-benzoyl-DL-arginine para-nitroanilide-HCl (BAPNA) and H-D-valyl-L-leucyl-L-lysine-p-nitroanilide-2HCl (S-2251), respectively. In extracts from both human and ovine acrosomes, the activities of acrosin and plasminogen activators were susceptible to tannic acid inhibition. The inhibitory effect of tannic acid was observed at concentrations > 50 micromol l(-1) in a dose-dependent manner. In additional experiments, low concentrations of tannic acid significantly inhibited tissue-type plasminogen activator, urokinase-type plasminogen activator and plasmin activity in a concentration-dependent manner over the range 0.25-200 micromol l(-1). Tannic acid reduced the motility of ram spermatozoa at a concentration of 1000 micromol l(-1) after 2 and 3 h co-incubation with spermatozoa. The motility of human spermatozoa remained unchanged over the range 0.1-1000 micromol tannic acid l(-1) during 3 h co-incubation. These results indicate that tannic acid inhibited the activity of both acrosin and plasminogen activator and indicates a possible mechanism by which flavonoids exert their antifertility effects.
评估了常见黄酮类化合物单宁酸对人和公羊精子顶体酶、纤溶酶原激活物活性及纤溶酶活性的影响。分别使用生色底物N-α-苯甲酰-DL-精氨酸对硝基苯胺盐酸盐（BAPNA）和H-D-缬氨酰-L-亮氨酰-L-赖氨酸对硝基苯胺-2盐酸盐（S-2251），通过分光光度法测定顶体酶和纤溶酶原激活物活性。在人和羊顶体提取物中，顶体酶和纤溶酶原激活物的活性均易受单宁酸抑制。单宁酸浓度>50 μmol l⁻¹时呈现剂量依赖性抑制作用。在额外实验中，低浓度单宁酸在0.25 - 200 μmol l⁻¹范围内以浓度依赖性方式显著抑制组织型纤溶酶原激活物、尿激酶型纤溶酶原激活物及纤溶酶活性。单宁酸与公羊精子共同孵育2小时和3小时后，在1000 μmol l⁻¹浓度下可降低其活力。在与人类精子共同孵育3小时期间，单宁酸浓度在0.1 - 1000 μmol l⁻¹范围内，精子活力保持不变。这些结果表明单宁酸抑制了顶体酶和纤溶酶原激活物的活性，并揭示了黄酮类化合物发挥抗生育作用的一种可能机制。
