Produção de IL-1β E IL-6 em explantes ex vivo de endométrio de vacas nelore e mestiças tratadas com LPS e esteroides ovarianos

Abstract

CAPÍTULO 2 - Uterine infections often affect dairy cows in the postpartum period, causing significant losses in reproductive performance. However, these uterine diseases are less frequent and important in beef cows when compared to dairy cows. The hypothesis of this study was that the endometrium of crossbred dairy cows (Bos 27 taurus x Bos indicus) when challenged with lipopolysaccharide (LPS) presents a different inflammatory response compared to Nellore (Bos indicus) females and that these responses are influenced by ovarian steroid hormones. This study aimed to evaluate the innate immune response of ex vivo bovine endometrium from beef (Nelore) and dairy (crossbred) cows when challenged with lipopolysaccharide (LPS) at different concentrations, exposure times and progesterone or estradiol hormone pretreatments. For this purpose, thirty-two reproductive traits were used from Nelore (n=15) and crossbred dairy (n=17) postpubertal cows, also blood samples to measure progesterone (P4) at the time of slaughter were collected. Endometrial tissues (explants) were collected and cultured for 24 or 48 hours in a control medium or medium containing LPS (1 or 2 μg/mL), and or pretreatment with estradiol (3 pg/mL) or progesterone (5 pg/mL). Supernatants were harvested for IL-1Β and IL-6 dosage. There was no difference in the accumulation of IL-1β and IL-6 between breeds when challenged with both LPS concentrations (1 or 2 μg/mL) in the cell culture medium. Pretreatment with progesterone or estradiol did not interfere in the production of these interleukins. It was concluded that ex vivo organ cultures of bovine endometrium from beef (Nelore) and dairy (crossbred) cows show similar production of IL-1Β and IL-6 when challenged with LPS and that this response was not affected by the estrous cycle stages, exogenous steroid hormones in response to challenge with LPS in the cell culture medium.