Ileana Miclea


THE EFFECT OF SEVERAL ASCORBIC ACID CONCENTRATIONS ON SWINE OOCYTE MATURATION AND EMBRYO CULTURE

Ileana Miclea, M. Zahan, A. Rusu, F. Ghiuru, V. Miclea

Abstract
Considering that free radicals are easily formed both in vivo and in vitro and that swine oocytes and embryos have a high content of unsaturated and therefore highly oxidizable fatty acids antioxidants must be added to the culture media. Ascorbic acid has been shown to improve swine oocyte maturation and the development of bovine and swine embryos. The goal of this study was to establish the influence of several ascorbic acid and a-tocopherol concentrations on swine oocyte maturation in order to improve oocyte maturation media. Pig oocytes were cultured for 44 hours at 37°C in 5% CO2 atmosphere, in M199 containing several ascorbic acid (50, 150, 250, 500 and 750 μM) concentrations. Oocytes were fertilized and the embryos were cultured for another 94 hours in TALP medium containing the same antioxidant concentrations. The addition of 50, 150, 500 and 750 mM ascorbic acid to the maturation medium lead to an increase in the number of oocytes assessed as 3 and 4 and a decrease in the number assessed with 0. The number of embryos that developed in medium supplemented with 50 μM ascorbic acid was significantly higher than the contro, thus proving the beneficial influence of ascorbic acid on embryo development.

Key words: antioxidant, swine oocytes, embryos, ascorbic acid

EFECTUL UNOR CONCENTRATII DE ACID ASCORBIC ASUPRA MATURARII OVOCITARE SI CULTURII EMBRIONILOR SUINI

Ileana Miclea, M. Zahan, A. Rusu, F. Ghiuru, V. Miclea

Rezumat
Usurinta cu care radicalii liberi se formeaza atāt in vivo cāt si in vitro dar si continutul mare de acizi grasi nesaturati si deci usor oxidabili al ovocitelor si embrionilor suini determina necesitatea adaugarii de antioxidanti la mediul de cultura. Dintre acestia a fost ales acidul ascorbic, datorita capacitatii sale antioxidante recunoscute si pentru ca cercetari anterioare au indicat efecte benefice īn cultura. Scopul acestui studiu a fost acela de a determina influenta unor concentratii de acid ascorbic asupra maturarii ovocitare si cdezvoltarii embrionilor suini. Īn acest scop ovocitele au fost cultivate timp de 44 ore, la 38°C īn 5% CO2 īn aer, īn mediu M199 continānd 50, 150, 250, 500 sau 750 μM acid ascorbic. Consecutiv maturarii s-a trecut la fecundatie si cultivarea embrionilor cu aceleasi concentratii de acid ascorbic īn mediu TALP timp de 94 ore. Aditia acidului ascorbic la mediul de cultura īn concentratii de 50, 150, 500, 750 ?M a dus la cresterea procentelor de ovocite notate cu 3 si la scaderea celor notate cu 0. Deasemenea, antioxidantul nu avut o influenta negativa asupra expandarii cumulus si respectiv maturarii. Numarul de embrioni care s-au dezvoltat īn mediu suplimentat cu 50 ?M acid ascorbic a fost semnificativ mai mare decāt īn cazul martorului indicānd un efect pozitiv.

Cuvinte cheie: antioxidant, ovocite suine, embrioni, acid ascorbic