IFIBYNE   05513
INSTITUTO DE FISIOLOGIA, BIOLOGIA MOLECULAR Y NEUROCIENCIAS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Is ovarian hyporesponse owing to ovarian ageing reversible in mice?
Autor/es:
KOPCOW L.; YOVANOVICH, C.; QUINTANA R; LOMBARDI E.; YOUNG E.; AUGE L.; PAZ D.A.
Lugar:
Praga, República Checa
Reunión:
Congreso; 22nd Annual Meeting of The European Society of Human Reproduction and Embryology; 2006
Resumen:
Introduction: It is well known that maternal age in some animals is associated with reduced fertility. I humans, woman’s age is a predictor of ovarian response and there is a decline in folliculogenesis at older ages. This situation is also present in mice. Older mice show a decrease in fertility, follicle development and ovulation. The average litter size of female mice declines with increasing age. The primordial cause of this situation still needs to be determined. The hypothesis of an insufficient vascular network could be valid. We have previously demonstrated that direct vascular endothelial growth factor (VEGF) injection into mice ovary enhances vascular network promoting an increment in follicular development and diminishing apoptosis. In this study, we evaluated whether VEGF injection into the ovary of aged mice reverts the decline in response to ovarian hyperstimulation owing to ageing. Materials and methods: We performed a controlled laboratory study on 10 Balb/c female mice of 8 weeks old and 9 Balb/c female mice of 11 months old. Young mice were treated as follow: right ovaries were injected with 0.1 ml of saline solution and 2 weeks later mice were stimulated with 7.5 IU PMSG during estrus. After 48 h they were injected with 10 IU of hCG (i.p.). Two hours later they were sacrificed. Older mice: right ovaries were injected with 0.1 ml of VEGF (0.2 ug) and 2 week later mice were hyperstimulated as the young group. To hours later they were sacrificed.   Group 1 represents right ovaries of young mice. Group 2 represents left ovaries of older mice and group 3 represents right ovaries of older mice (injected previously with VEGF).   Number of antral follicles was evaluated in each group. Statistical analysis: Statistical comparisons were performed by Student’s t-test and Kruskal-Wallis  non-parametric ANOVA test. Only a p<0.05 was considered significant. Results: The number of antral follicles observed in different groups was as follows: Group 1: 11.37+0.65; group 2: 6+1.41421; and group 3: 9.66+1.58. The number of antral follicles observed in ovaries treated with VEGF was significantly higher that in contralateral ones (p<0.001). The difference between Group 1 and Group 2 also reached a significant difference (p<0.001). Moreover, the difference between Groups 2 and 3 showed significance (p<0.01). Conclusion: Ovarian VEGF injection has a positive effect on ovarian response in aged mice.