The endometrial expression of interleukin-1 family: their involvement in delayed conception of dairy cows

CAINELLI S; PERALTA MB; ANGELI E; STASSI AF; SALVETTI NR; ORTEGA HH; REY F; VELAZQUEZ MML

Congreso; Reunión Conjunta SAIC SAI AAFE NANOMED; 2021

Thecytokines of the interleukin-1 family are closely involved in processes such asresolution of uterine inflammation and are locally produced by macrophages andendometrial cells under stimuli. However, little is known about the role ofthese cytokines in the absence of disease during postpartum period whereconception and pregnancy occur in cattle. The aim of this study was to analysethe gene and protein expression levels of the members of IL-1 family: IL-1α,IL-1β, IL-1RI, IL-1RII and IL-1RA during postpartum period, and their possibleassociation with delayed conception. Endometrial biopsies were obtained frommultiparous Holstein cows (n=16) at 45 and 60 days in milk (DIM). The voluntarywaiting period of cows was 70 days. All procedures were approved by the Ethics Committee(FCV-UNL). The gene expression of IL-1α, IL-1β, IL-1RI, IL-1RII and IL-1RA wasanalyzed by real-time PCR. The immunolocalization of the cytokines was assessedby indirect immunohistochemistry. Kaplan?Meier test was used to evaluate thepossible association between the gene and protein levels of each cytokine anddelayed conception. Then, when the results from Kaplan-Meier showed significantassociation, we grouped the animals like ?fewer number of days to conception?(FDC) and ?greater number of days to conception? (GDC) for comparison. Toanalyze the differential expression levels over time in FDC and GDC groups, aGeneralized Linear Model was used considering DIM as a fixed factor. The geneexpression of all members of IL-1 family showed no significant association withdelayed conception. However, the association between the protein expression ofIL-1β and IL-1RA in glandular epithelium (GE) and delayed conception wassignificant. Then, the GLM showed no significant differences in GE between 45and 60 DIM, both in the FDC and GDC group. These results suggest a potentialrole of some members from IL-1 family, as IL-1β and IL-1RA, in the mechanisms involvedto early conception.