Expression and localization of insulin-like growth factor gene family members in the caprine ovarian and uterine tissues during different pregnancy stages

Abstract

Goats are of significant economic importance, yet our knowledge of the molecular pathways involved in their pregnancy remains limited. This study aims to investigate the role of IGFs in uterine and ovarian cellular events during pregnancy in goats. Forty-two Hair Goats were examined, including four pregnancy groups representing embryo- positive (G1, n=7), early (G2, n=7), mid (G3, n=7), and late pregnancy (G4, n=7), as well as two luteal stage groups representing early (G5, n=7) and late (G6, n=7) phases. Uterine and ovarian tissues were collected, and RT-qPCR and immunohistochemistry were performed to evaluate IGF expression. The results showed that IGF1 and IGF2 expressions were significantly higher in G1 than in other pregnancy and control groups (p < 0.05). Additionally, IGFBP1 expression was higher in G2 than in G1 and G4 (p < 0.05), and IGFBP3 expression was higher in G4 than in any other pregnancy stage (p < 0.05). However, no statistically significant differences were observed in the expression levels of IGFBP4 and IGFBP6 between any of the groups. Finally, IGFBP5 expression was significantly higher in G1, G3, and G4 compared to G2 (p < 0.05). Overall, the dynamic changes observed in the expression of the IGF gene family during different stages of pregnancy highlight the crucial role of IGFs in regulating pregnancy in goats.