EFFECT OF DIMETHYL THIOUREA ON NUCLEAR MATURATION AND APOPTOSIS OF PORCINE OOCYTES

LORENZO, MS.; TELLO, MF.; CRUZANS, PR.; MARURI, A.; LOMBARDO, DM.

Ciudad Autónoma de Buenos Aires

Jornada; IV Jornadas Internacionales del Instituto de Investigación y Tecnología en Reproducción Animal; 2014

Instituto de Investigación y Tecnología en Reproducción Animal

balanced redox environment is signifi cant for oocyte quality. An increase in the production of oxygen reactive species aff ects oocyte viability. Th e use of antioxidant during the collection of cumulus oocyte complexes (COCs) it is not reported in porcine. Th e aim of this study was evaluate the effect of dimethylthiourea (DMTU) on in vitro maturation (IVM) and early and late apoptosis of porcine oocytes. COCs were collected by follicular aspiration from slaughterhouse ovaries. In the control group the collection medium used was TCM-199 and the washing medium was TCM -199 supplemented with 10% porcine follicular fl uid and penicillin streptomycin. In treatments 2 mM and 20 mM of DMTU was added to both media. Oocyte completely surrounded by cumulus cells were selected to mature in vitro. Th e determinations were performed after 44-48 h of IVM. Oocytes were denuded, fi xed and stained with Hoechst 33342 for the evaluation of IVM rate; oocytes with metaphase II nuclear confi guration were considered mature. Early apoptosis was evaluated in fresh and denuded oocytes by Annexin Vpropidium iodide (Invitrogen ®). Late apoptosis was measured in fi xed and denuded oocytes by TUNEL assay (In Situ Cell Death Detection Kit Roche®). Statistical analysis was performed with Infostat software (p< 0.05). Th ere were no statistically signifi cant diff erences in nuclear maturation rates (57,4%, n=97 control; 53,65%, n=123 treatment 2 mM y 49,63% n= 137 treatment 20 mM) neither in the percentage of early (2,52%, n=119 control; 0,58%, n= 173 treatment 2 mM y 0%, n=122 treatment 20 mM) and late oocyte apoptosis (2,9%, n=103 control; 2,4%, n=85 treatment 2 mM y 0,83%, n=120 treatment 20 mM). We concluded that the addition of DMTU to collection medium (at the concentrations used) did not modify the rates of nuclear maturation and apoptosis in porcine oocytes. In future, the eff ects of DMTU supplementation in ROS production and oocyte cytoplasmic maturation will be evaluated.