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RESEARCH ARTICLE

Effects of the addition of insulin–transferrin–selenium (ITS) and/or metformin to the in vitro maturation of porcine oocytes on cytoplasmic maturation and embryo development

Carolina Griselda Luchetti https://orcid.org/0000-0003-3944-5093 A B , María Soledad Lorenzo A B , Evelin Mariel Elia C D E , Gabriela Maia Teplitz A B , Paula Romina Cruzans A B , María Clara Carou https://orcid.org/0000-0001-9657-9464 A and Daniel Marcelo Lombardo https://orcid.org/0000-0003-0677-7702 A B *
+ Author Affiliations
- Author Affiliations

A Universidad de Buenos Aires, Facultad de Ciencias Veterinarias, Instituto de Investigación y Tecnología en Reproducción Animal, Cátedra de Histología y Embriología, Chorroarín 280, Buenos Aires C1427CWO, Argentina.

B Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2290, Buenos Aires C1425FQD, Argentina.

C Universidad de Buenos Aires (UBA), Facultad de Ciencias Exactas y Naturales (FCEN), Intendente Güiraldes 2160, Ciudad Universitaria, Buenos Aires C1428EGA, Argentina.

D Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)-UBA- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina.

E UBA, FCEN, Departamento de Biodiversidad y Biología Experimental, Buenos Aires, Argentina.

* Correspondence to: dlombard@fvet.uba.ar

Handling Editor: Ye Yuan

Reproduction, Fertility and Development 35(5) 363-374 https://doi.org/10.1071/RD22254
Published online: 14 February 2023

© 2023 The Author(s) (or their employer(s)). Published by CSIRO Publishing

Abstract

Context: One of the main problems of porcine in vitro maturation (IVM) is incomplete cytoplasmatic maturation. Nuclear and cytoplasmic maturation will determine the future success of fertilisation and embryo development. Insulin–transferrin–selenium (ITS) has insulin-like and antioxidant effects, and metformin (M) is an insulin-sensitiser and antioxidant drug.

Aims: To assess the effects of adding ITS and/or M in porcine IVM media on cytoplasmic maturation and early embryo development.

Methods: Cumulus-oocyte complexes (COC) were IVM with M (10−4M), ITS (0.1% v/v), M + ITS or no adding (Control).

Key results: ITS increased glucose consumption compared to Control and M (P < 0.01), and M + ITS did not differ from ITS or Control. Redox balance: M, ITS and M + ITS increased glutathione (P < 0.01) and decreased lipid peroxidation (P < 0.005). The viability of cumulus cells by flow cytometry increased with M (P < 0.005) and decreased with ITS (P < 0.001); M + ITS did not differ from Control. After IVF, M increased penetration and decreased male pronucleus (P < 0.05). Embryo development: cleavage increased with M (P < 0.05), and blastocysts increased with ITS and M + ITS (P < 0.05). The number of blastocyst cells increased with ITS (P < 0.05).

Conclusions: Adding ITS and M + ITS to porcine IVM media benefits embryo development to blastocysts, but ITS alone has better effects than M + ITS.

Implications: ITS is an excellent tool to improve IVM and embryo development after IVF in pigs.

Keywords: antioxidant, blastocyst, cumulus cells, glucose, IVF, IVM, IVP, oxidative stress, polyspermy, redox balance.


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