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Updated: May 16, 2026

A Modified Co-Culture System for Understanding Granulosa-Theca Cell Interactions in the Bovine Ovary
Published on: September 19, 2025
Interleukin-8 stimulates progesterone production via the MEK pathway in ovarian theca cells
Takashi Shimizu1, Eri Imamura, Fumie Magata
1Graduate School of Animal and Food Hygiene, Obihiro University of Agriculture and Veterinary Medicine, Inada-machi, Obihiro, Hokkaido, 080-8555, Japan. shimizut@obihiro.ac.jp
Abstract:
Interleukin 8 (IL-8) is a chemoattractant associated with ovulation in the mammalian ovary. This chemokine is also involved in the recruitment and activation of neutrophils. Using bovine tissue, we examined the possible role of IL-8 in steroid production by theca cells of the large ovarian follicles. IL-8 promoted progesterone production and stimulated StAR expression in cultured theca cells. The inhibitor of p38 did not disturb the P4 production and StAR expression in IL-8-treated theca cells. On the other hand, the inhibitor of MEK disturbed the P4 production and expression of StAR in theca cells treated with IL-8. These results suggest that IL-8 is associated with progesterone production in bovine theca cells via the MEK pathway.
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