title: Antihyaluronidase action of ellagic acid effectively prevents polyspermy as a result of suppression of the acrosome reaction induced by sperm-zona interaction during in vitro fertilization of porcine oocytes.
abstract: The present study was conducted to examine the effects of three tannin relatives (tannic acid, TA; gallic acid, GA; and ellagic acid, EA) on antihyaluronidase and reactive oxygen species (ROS) scavenging activity, in vitro fertilization (IVF) parameters, and the acrosome reaction (AR) induced by sperm-zona interaction. Among the three tannin relatives, TA and EA showed the strongest potency for blocking the hyaluronidase activity of boar sperm, with concentration-dependent inhibition over the range of 2-10 microg/ml. In contrast, ROSs were effectively scavenged by TA and GA, but not EA. When cumulus-free oocytes were inseminated in IVF medium containing 5 microg/ml of the tannin relatives, polyspermy was significantly reduced by TA and EA (32 and 29%, respectively) compared with oocytes treated with or without GA (51 and 69%, respectively) under conditions that maintained a high sperm penetration rate (P<0.05). Interestingly, induction of the AR by treatment of preincubated sperm with progesterone was blocked by TA and GA as a result of their higher levels of ROS scavenging activity, while EA, which possessed weak ROS scavenging activity, did not disturb induction of the AR with progesterone. However, the incidence of AR induced by sperm-zona interaction was significantly decreased by the strong antihyaluronidase actions of TA and EA compared with that in the absence of these compounds. Treatment with the compounds caused neither a protective proteolytic modification of the zona pellucida matrix before fertilization nor a reduction in acrosomal proteolytic activity or the number of zona-bound sperm. These findings suggest that the antihyaluronidase action of EA effectively prevents polyspermy by suppression of AR functionality induced by sperm-zona interaction and that hyaluronidase intervention is therefore required during porcine IVF.
authors: Faculty of Agriculture, University of the Ryukyus, Nishihara, Okinawa, Japan.
authors: Isao
authors: I
authors: Tokeshi
authors: Teppei
authors: T
authors: Yoshimoto
authors: Norio
authors: N
authors: Muto
authors: Satoshi
authors: S
authors: Nakamura
authors: Koji
authors: K
authors: Ashizawa
authors: Tadashi
authors: T
authors: Nakada
authors: Hideki
authors: H
authors: Tatemoto
mesh_terms: D020101:Acrosome Reaction / Q000187:drug effects*; D000818:Animals; D004610:Ellagic Acid / Q000494:pharmacology*; D004789:Enzyme Activation / Q000187:drug effects; D005260:Female; D005306:Fertilization / Q000187:drug effects; D005307:Fertilization in Vitro / Q000379:methods / Q000662:veterinary*; D016166:Free Radical Scavengers / Q000494:pharmacology; D005707:Gallic Acid / Q000494:pharmacology; D006821:Hyaluronoglucosaminidase / Q000037:antagonists & inhibitors*; D008297:Male; D013084:Sperm-Ovum Interactions / Q000187:drug effects*; D013094:Spermatozoa / Q000187:drug effects / Q000201:enzymology; D013552:Swine; D013634:Tannins / Q000494:pharmacology; D015044:Zona Pellucida / Q000187:drug effects / Q000201:enzymology
chemical_list: D016166:Free Radical Scavengers; D013634:Tannins; D004610:Ellagic Acid; D005707:Gallic Acid; D006821:Hyaluronoglucosaminidase