Aminoacid metabolism during in vitro maturation of the bovine oocyte

MARTINEZ S; GUTNISKY C; BREININGER E; CETICA PD

Congreso; IV Reunión Conjunta de Sociedades de Biología de la República Argentina; 2021

Glucose represents the main oxidative substrate present in the maturation media during the in vitro maturation process of the bovine cumulus-ocomplex (COC). However, little is known about the role of amino acids during this process. The aim of this work was to study the bovine ometabolism in a medium supplemented only with amino acids as oxidative substrates. COCs were obtained by aspiration of antral fol liclesovaries from slaughter cows. Those COCs with dense and compact cumulus were selected. Maturation was carried out in SOF medium (wpyruvate or lactate) supplemented with FSH, LH, EGF, gentamicin, insulin and PVA, under mineral oil at 39ºC and 5% CO2 in humidified air hours. The COCs were randomly divided into 4 groups supplemented as follows: (a) SOF (C1 ), (b) SOF + Amino Acids (T), (c) SGlucose/Amino Acids (C+), and (d) SOF + Salicylate (Glutamate Dehydrogenase inhibitor) (C2 ). Nuclear maturation was evaluated using Ho33342 fluorescent staining, observing the presence of metaphase plate II. To study the metabolism of amino acids, the concent ration of ammonidetermined at the end of maturation using a spectrophotometric technique based on the oxidation of NADPH by the enzyme GlutDehydrogenase. A significant increase in the nuclear maturation percentage was observed in COCs matured in the group supplemented with acids (T) compared to both negative control groups (C1 and C2 ) (P < 0.05). Maturation in the media supplemented with amino acids (Tlower than the positive control (C +) (P < 0.05). In ammonia production a significant increase was observed in the medium supplemented with aacids (T) (P < 0.05). From these results it turns that the amino acids during in vitro maturation of bovine oocytes are deaminated to obtain cskeletons as an energy source. The maturation is hold partly by the energy that comes out from the carbon skeletons of amino acids.