title: Addition of L-arginine to the fertilization medium enhances subsequent bovine embryo development rates.
abstract: Although L-Arginine (ARG) has been reported as a promising bovine sperm capacitation agent, its effects on embryo development are still poorly understood. Herein, we compared the effects of ARG and/or heparin (HEP) addition to the fertilization medium for bovine oocytes on sperm capacitation and embryo development. We chose 10 mM ARG based on blastocyst development rates in a titration experiment. Addition of ARG and/or HEP to the fertilization medium resulted in similar rates of blastocyst development (P > 0.05). However, when ARG, but not HEP, was combined with a nitric oxide (NO) synthase inhibitor (N-Nitro-L-ARG-methyl ester, 10 mM) blastocyst development was decreased (P < 0.05). To assess the effects on capacitation, bovine sperm were incubated for 0, 3, and 6 hours in fertilization medium containing ARG and/or HEP and/or N-Nitro-L-ARG-methyl esterand acrosomal exocytosis rates were evaluated using fluorescein isothiocyanate conjugated Pisum sativum lectin (FITC-PSA) staining and flow cytometry. With HEP, acrosomal exocytosis rates were highest by 3 hours of incubation; however, by 6 hours, rates were similar for HEP and/or ARG (P > 0.05) and higher than those in control media (P < 0.05). Although both ARG and HEP increased sperm NO production (P < 0.05), combination with L-NAME only precluded acrosomal exocytosis when ARG added alone in the medium (P > 0.05). These results suggest that although both ARG and HEP supported sperm capacitation, only the effects of the former were driven via NO production. Moreover, ARG was also as effective as HEP at improving blastocyst development rates. Therefore, ARG may be used as a low-cost alternative sperm capacitation agent for bovine in vitro embryo production.
authors.affiliation: Department of Biology, Federal Rural University of Amazon, Capitão-Poço, Pará, Brazil. Electronic address: ppbsantana@gmail.com.
authors.forename: Priscila P B
authors.initials: PP
authors.lastname: Santana
authors.affiliation: Institute of Biological Sciences, Federal University of Pará, Belém, Pará, Brazil.
authors.forename: Bruno B
authors.initials: BB
authors.lastname: da Silva
authors.affiliation: Institute of Biological Sciences, Federal University of Pará, Belém, Pará, Brazil.
authors.forename: Thiago V G
authors.initials: TV
authors.lastname: Silva
authors.affiliation: Institute of Biological Sciences, Federal University of Pará, Belém, Pará, Brazil.
authors.forename: Nathalia N
authors.initials: NN
authors.lastname: Costa
authors.affiliation: Federal Institute of Education, Science and Technology of Pará, Castanhal, Pará, Brazil.
authors.forename: Marcela S
authors.initials: MS
authors.lastname: Cordeiro
authors.affiliation: Institute of Biological Sciences, Federal University of Pará, Belém, Pará, Brazil.
authors.forename: Simone S D
authors.initials: SS
authors.lastname: Santos
authors.affiliation: Institute of Biological Sciences, Federal University of Pará, Belém, Pará, Brazil.
authors.forename: Otávio M
authors.initials: OM
authors.lastname: Ohashi
authors.affiliation: Institute of Biological Sciences, Federal University of Pará, Belém, Pará, Brazil.
authors.forename: Moysés S
authors.initials: MS
authors.lastname: Miranda
mesh_terms: D000818:Animals; D001120:Arginine / Q000494:pharmacology*; D002417:Cattle; D003470:Culture Media; D046149:Embryo Culture Techniques / Q000662:veterinary*; D004622:Embryo, Mammalian / Q000187:drug effects*; D047108:Embryonic Development / Q000187:drug effects*; D005260:Female; D005307:Fertilization in Vitro / Q000662:veterinary; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000502:physiology; D013075:Sperm Capacitation / Q000187:drug effects
chemical_list: D003470:Culture Media; D009569:Nitric Oxide; D001120:Arginine; D019001:Nitric Oxide Synthase
keywords: Acrosomal exocytosis; Bovine; IVF; L-arginine; Nitric oxide