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Analyses of apoptosis and DNA damage in bovine cumulus cells after in vitro maturation with different copper concentrations: consequences on early embryo development

Published online by Cambridge University Press:  01 November 2016

D.E. Rosa ,
J.M. Anchordoquy ,
J.P. Anchordoquy ,
M.A. Sirini ,
J.A. Testa ,
G.A. Mattioli  and
C.C. Furnus
D.E. Rosa
Affiliation:
Cátedra de Fisiología, Laboratorio de Nutrición Mineral, Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata, calle 60 y 118 s/n, CP (1900), La Plata, Buenos Aires, Argentina.
J.M. Anchordoquy
Affiliation:
Instituto de Genética Veterinaria Prof. Fernando N. Dulout (IGEVET), Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata - CONICET, calle 60 y 118 s/n, CP (1900), La Plata, Buenos Aires, Argentina. Cátedra de Fisiología, Laboratorio de Nutrición Mineral, Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata, calle 60 y 118 s/n, CP (1900), La Plata, Buenos Aires, Argentina.
J.P. Anchordoquy
Affiliation:
Instituto de Genética Veterinaria Prof. Fernando N. Dulout (IGEVET), Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata - CONICET, calle 60 y 118 s/n, CP (1900), La Plata, Buenos Aires, Argentina. Cátedra de Fisiología, Laboratorio de Nutrición Mineral, Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata, calle 60 y 118 s/n, CP (1900), La Plata, Buenos Aires, Argentina.
M.A. Sirini
Affiliation:
Instituto de Genética Veterinaria Prof. Fernando N. Dulout (IGEVET), Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata - CONICET, calle 60 y 118 s/n, CP (1900), La Plata, Buenos Aires, Argentina.
J.A. Testa
Affiliation:
Instituto de Genética Veterinaria Prof. Fernando N. Dulout (IGEVET), Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata - CONICET, calle 60 y 118 s/n, CP (1900), La Plata, Buenos Aires, Argentina.
G.A. Mattioli
Affiliation:
Cátedra de Fisiología, Laboratorio de Nutrición Mineral, Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata, calle 60 y 118 s/n, CP (1900), La Plata, Buenos Aires, Argentina.
C.C. Furnus*
Affiliation:
Instituto de Genética Veterinaria Prof. Fernando N. Dulout (IGEVET), Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata - CONICET, calle 60 y 118 s/n, CP (1900), La Plata, Buenos Aires, Argentina Instituto de Genética Veterinaria Prof. Fernando N. Dulout (IGEVET), Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata - CONICET, calle 60 y 118 s/n, CP (1900), La Plata, Buenos Aires, Argentina. Cátedra de Citología, Histología y Embriología ‘A’, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, calle 60 y 118 s/n, CP (1900), La Plata, Buenos Aires, Argentina.
*
All correspondence to: C.C. Furnus. Instituto de Genética Veterinaria Prof. Fernando N. Dulout (IGEVET), Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata - CONICET, calle 60 y 118 s/n, CP (1900), La Plata, Buenos Aires, Argentina Tel:/Fax: +54 0221 421 1799. E-mail: cfurnus@fcv.unlp.edu.ar
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Summary

The aim of this study was to investigate the influence of copper (Cu) during in vitro maturation (IVM) on apoptosis and DNA integrity of cumulus cells (CC); and oocyte viability. Also, the role of CC in the transport of Cu during IVM was evaluated on oocyte developmental capacity. Damage of DNA was higher in CC matured without Cu (0 µg/dl Cu, P < 0.01) with respect to cells treated with Cu for cumulus–oocyte complexes (COCs) exposed to 0, 20, 40, or 60 µg/dl Cu). The percentage of apoptotic cells was higher in CC matured without Cu than in CC matured with Cu. Cumulus expansion and viability of CC did not show differences in COC treated with 0, 20, 40, or 60 µg/dl Cu during IVM. After in vitro fertilization (IVF), cleavage rates were higher in COC and DO + CC (denuded oocytes + CC) with or without Cu than in DO. Independently of CC presence (COC, DO + CC or DO) the blastocyst rates were higher when 60 µg/dl Cu was added to IVM medium compared to medium alone. These results indicate that Cu supplementation to IVM medium: (i) decreased DNA damage and apoptosis in CC; (ii) did not modify oocyte viability and cumulus expansion; and (iii) improved subsequent embryo development up to blastocyst stage regardless of CC presence during IVM.

Keywords

ApoptosisDNA damageEarly developmentMinerals

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Type
Research Article
Information
Zygote , Volume 24 , Issue 6 , December 2016 , pp. 869 - 879
Copyright
Copyright © Cambridge University Press 2016 

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