Effect of metritis on endometrium tissue transcriptome during puerperium in Holstein lactating cows

Abstract

The objective of this prospective cohort study was to evaluate the effect of parity and uterine healthstatus postpartum on the gene expression profile of the endometrium early post-partum. Twenty-fourHolstein cows were randomly selected (16 multiparous (MP) and 8 primiparous (PP)) and endometriumbiopsies were collected on days 1, 3, and 6 after calving and clinically monitored for metritis. Rectaltemperature was measured twice and fever was defined as a temperature 39.5 C. A case of metritiswas diagnosed with the presence of red-brown watery, foul-smelling uterine discharge or a purulentdischarge with more than 50% pus and fever between days 1 and 6 postpartum. Cows were thenretrospectively selected (cows diagnosed with metritis were paired with healthy ones) to analyze theexpression of 66 genes measured on the NanoString nCounter Analysis System. The genes selected wererelated with adhesion, immune system, steroid and prostaglandin biosynthesis regulation, insulinmetabolism and transcription factors, and nutrient transporters. The results indicated a different patternon genes related to immune function by parity.PTX3,involved in antigen presentation, was increased inhealthy MP compared with healthy PP whereas inflammatory cytokineTNFaand complement-relatedproteinSERPING1was upregulated in MP compared with PP (P<0.05). As expected, presence of ametritis condition affected the expression of genes related to immune function. There was an increasedexpression of the antiviral factorMX2andMYH10gene, which is involved in macrophages recruitment, inmetritic compared with healthy cows (P<0.05). Differences in uterine involution from cows diagnosedwith metritis were reflected by the downregulation ofIGF1(P<0.10), involved in endometriumremodeling, and a possible compensatory upregulation of its receptorIGFR1(P<0.05). A greaterexpression of prostaglandins and oxytocin receptors (PGRandOXTR), involved in the involution process,were observed in metritic PP compared with healthy PP (P<0.05). Overall, it seems that metritissignificantly modulate processes closely tied with the physical involution of the uterus early post-partum(IGF1, IGFR1, PGR, OXTR), whereas both metritis and multiparous cows tended to upregulate genes relatedto immune response (PTX3, TNFa, SERPING1, MX2, MYH10).