Reduction of acyloxyacyl hydrolase activity in circulating neutrophils from cows after parturition.

Abstract

Bovine neutrophils contain the enzyme acyloxyacyl hydrolase, which hydrolyzes the acyloxyacyl linkage of the two nonhydroxylated fatty acyl chains to two 3-hydroxy fatty acids in the highly conserved lipid A part of endotoxins with high specificity. This hydrolysis decreases the toxicity of lipid A, but the immunostimulatory capacity of endotoxins is largely maintained. In two trials, we studied the activity of acyloxyacyl hydrolase in neutrophils that had been isolated from the blood of 18 dairy cows around parturition. Between 10 and 26 d after parturition, the activity of acyloxyacyl hydrolase in neutrophils decreased approximately 20% below prepartum activity. At about 2 mo after parturition, acyloxyacyl hydrolase activity returned to prepartum values. Changes in acyloxyacyl hydrolase activity could not be attributed to changes in binding of lipopolysaccharides by the CD14 molecules on neutrophils or monocytes. We hypothesize that decreased acyloxyacyl hydrolase activity in neutrophils shortly after parturition is a factor that increases the susceptibility of dairy cows to coliform mastitis during early lactation.

• Authors: H Dosogne, A V Capuco, M J Paape, E Roets, C Burvenich, B Fenwick
• Journal: Journal of dairy science (J Dairy Sci) Vol. 81 Issue 3 Pg. 672-7 (Mar 1998) ISSN: 0022-0302 [Print] United States
• PMID: 9565869 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.)

Chemical References

• Endotoxins
• Lipid A
• Carboxylic Ester Hydrolases
• acyloxyacyl hydrolase

Topics

• Animals
• Carboxylic Ester Hydrolases (blood)
• Cattle (blood)
• Disease Susceptibility
• Endotoxins (metabolism)
• Female
• Lactation
• Lipid A (metabolism)
• Mastitis, Bovine (enzymology)
• Neutrophils (enzymology)
• Postpartum Period