Endocannabinoids as endometrial inflammatory markers in lactating Holstein cows

Area of Science:

• Veterinary Immunology
• Reproductive Biology
• Endocrinology

Background:

• The endocannabinoid system (ECS) regulates physiological functions.
• Inflammation significantly impacts bovine reproductive health, particularly the endometrium.
• Understanding ECS involvement in bovine endometritis is crucial for improving fertility.

Purpose of the Study:

• To investigate the endocannabinoid system as a marker of inflammation in the bovine endometrium.
• To elucidate the role of the ECS in regulating inflammatory conditions in cows post-partum.

Main Methods:

• Comparative analysis of healthy cows (n=7) and cows with subclinical endometritis (n=7) at 26 days post-partum.
• Measurement of plasma tumor necrosis factor (TNF) and lipopolysaccharide-binding protein (LBP).
• Real-time PCR analysis of mRNA expression for inflammatory markers and ECS components (CNR2, NAPEPLD, FAAH, NAAA) in uterine tissue.

Main Results:

• Subclinical endometritis cows exhibited higher plasma TNF and LBP concentrations than healthy cows.
• Uterine tissue from affected cows showed decreased mRNA expression of endocannabinoid-degrading enzymes (NAAA, FAAH).
• Uterine tissue from affected cows showed increased mRNA expression of the endocannabinoid receptor (CNR2) and a synthesis enzyme (NAPEPLD).

Conclusions:

• The endocannabinoid system is significantly altered in the bovine endometrium during inflammation.
• Increased expression of CNR2 and NAPEPLD, coupled with decreased FAAH and NAAA, suggests elevated endocannabinoid levels during endometritis.
• These ECS alterations may interfere with pro-cytokine signaling, influencing the onset and progression of uterine inflammation in cows.