Expression and regulation of tissue inhibitors of metalloproteinases (TIMP1 and TIMP3) in goat oviduct

Tissue inhibitors of metalloproteinases (TIMPs) are associated with several reproductive processes, such as mammalian follicular growth, ovulation, CL formation, and embryonic development. However, the expression and function of TIMPs in goat oviducts remain unclear. This work aimed to identify TIMP1 and TIMP3 expression in the goat oviduct during the estrous cycle via immunohistochemistry, real-time polymerase chain reaction (PCR), and functional studies in cultured goat oviductal epithelial cells. Real-time PCR results demonstrated that TIMP1 and TIMP3 messenger RNAs were expressed in all goat oviductal regions at all stages of the estrous cycle. TIMP1 and TIMP3 proteins were also highly expressed in oviductal epithelial cells with very limited expression in other cell types. Oviductal epithelial cells were treated in vitro with various estradiol concentrations (1-100 nM) for 24 hours. The findings showed that TIMP1 expression increased up to 20 nM but then gradually decreased, whereas no significant effects existed among TIMP3 messenger RNA levels. Time-course studies indicated that estradiol significantly increased TIMP1 expression in a time-dependent manner from 8 hours to 24 hours. By contrast, TIMP3 expression was transiently induced in oviductal epithelial cells at 2 and 4 hours after estradiol treatment. Furthermore, treatment with TIMP1 functionally increased the viability of cultured oviductal epithelial cells. Overall, the results suggested that the differential regulation and function between TIMP1 and TIMP3 might be associated with their unique roles in fertilization and early embryonic development.