Estrogen and progesterone endometrial cell receptors in cows with subclinical endometritis

Abstract

Pathological processes that strongly affect the uterine endometrium lead to infertility and abortion. The most common of these pathologies are clinical and subclinical endometritis. Subclinical endometritis is characterized by endometrial inflammation in the absence of clinical signs of endometritis. In this study, we used uterine samples obtained from Ukrainian black-and-white dairy cows aged 4 to 7 years to compare the histology of the uterine endometrium and changes in estrogen-α (ER-α), estrogen-β (ER-β) and progesterone (PgR) nuclear receptor sensitivity in cows with subclinical endometritis. Cows were separated based on cytological examination of the endometrium into a healthy group, or those presenting with subclinical endometritis. From these groups endometrial and epithelial tissue samples were obtained using biopsy forceps and an endoscope then analyzed using immunohistochemistry. Our results demonstrate that the sensitivity of ER-α and ER-β is lower while PgR sensitivity is elevated in cows with subclinical endometritis compared to the healthy control group. Additionally, we observed markedly altered histological changes characterized by enlargement of uterine glands, epithelial desquamation, and infiltration of leukocytes. These results suggest that there are significant changes in the endometrium linked to the sensitivity of nuclear steroid hormone receptors that may also play an immunoregulatory role in cows with subclinical endometriosis. While the interaction of steroid hormones and immunoregulation in the uterus remains to be elucidated, it may provide key insights into the uterine immune response.