Effects of IGF-1 on In Vitro Culture of Bovine Preantral Follicles are Dose-Dependent.
This study aimed at assessing the effect of different concentrations of the growth factor similar to insulin 1 (IGF-1) in the development, survival and ultrastructure of the bovine preantral follicles cultured in situ. Fragments of bovine ovarian cortical tissue were cultured during 1 and 7 days in 1 ml of α-MEM(+) , supplemented with different concentrations of human recombinant IGF-1 (0, 30, 70 and 100 ng/ml), in an incubator at 37°C and 5% of CO2 in 24-well plates with total replacement of the medium every 2 days. Non-cultured ovarian fragments (control) and ovarian fragments cultured during 1 and 7 days were processed for classic histology, mechanical isolation and electron transmission microscopy (ETM). Parameters such as normality, viability, activation, development, diameter and ultrastructure were evaluated. All statistical analyses were carried out using sas Version 9.2. The results showed that the percentage of follicles morphologically normal in the IGF-1 30 ng/ml treatment was similar to the fresh control (p > 0.05) both on the day 1 and on the day 7 of in vitro culture. In the viability analysis, the cultured treatments maintained the percentage of viable follicles during the entire culture period (p > 0.05). After 7 days of culture, the IGF-1 30 ng/ml treatment showed higher percentages of developing follicles (48.33%) than those of the fresh control (22.22%) and the cultured treatments (p < 0.05). Also, after 7 days of culture, IGF-1 30 ng/ml presented a higher follicular diameter when compared to the control and other concentrations of IGF-1 tested. Ultrastructurally, the non-cultured control and IGF-1 30 ng/ml, after 7 days of culture, showed conserved oocytes, nuclei and organelles. Hence, it is concluded that IGF-1 30 ng/ml was the most efficient concentration for the development of bovine preantral follicles cultured in vitro.
Departament of Animal Science, Laboratory of Animal Physiology and Reproduction, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
C R
CR
Jimenez
Departament of Animal Science, Laboratory of Animal Physiology and Reproduction, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
J L
JL
de Azevedo
Departament of Animal Science, Laboratory of Animal Physiology and Reproduction, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
R G
RG
Silveira
Departament of Animal Science, Laboratory of Animal Physiology and Reproduction, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
J
J
Penitente-Filho
Departament of Animal Science, Laboratory of Animal Physiology and Reproduction, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
E L
EL
Carrascal-Triana
Departament of Animal Science, Laboratory of Animal Physiology and Reproduction, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
A M
AM
Zolini
Laboratory of Manipulation of Oocytes Enclosed in Preantral Follicles, Universidade Estadual do Ceará, Fortaleza, CE, Brazil.
V R
VR
Araujo
Departament of Animal Science, Laboratory of Animal Physiology and Reproduction, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
Caa
C
Torres
Departament of Biology, Laboratory of Cellular Ultrastructure, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
W G
WG
Gonçalves
D000818:Animals; D002417:Cattle; D002467:Cell Nucleus / Q000648:ultrastructure; D003470:Culture Media; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000008:administration & dosage*; D009865:Oocytes; D015388:Organelles / Q000648:ultrastructure; D006080:Ovarian Follicle / Q000187:drug effects* / Q000254:growth & development* / Q000648:ultrastructure; D011994:Recombinant Proteins; D013997:Time Factors; D046509:Tissue Culture Techniques
D003470:Culture Media; D011994:Recombinant Proteins; D007334:Insulin-Like Growth Factor I