Acidosis and Lipopolysaccharide from Escherichia coli B:055 Cause Hyperpermeability of Rumen and Colon Tissues

Abstract

The objective of the present investigation was to evaluate the effects of acidic pH of the perfusate and presence of lipopolysaccharide (LPS) on permeability of rumen and colon mucosal tissues to mannitol and LPS using the Ussing chamber system. Rumen and colon tissues (n = 8), obtained from slaughtered feedlot steers, were tested for changes in permeability to (3)H-mannitol under pH of 4.5, 5.5, and 6.5 for rumen and at 5.5, 6.5, and 7.4 for colon, with or without LPS from Escherichia coli B:055 at 500 microg/mL. The (3)H-Mannitol was added at 10 microL (525.4 GBq/mmol) on the mucosal side of the Ussing chamber to detect changes in permeability, and 4 samples were taken at 20, 25, 30, and 35 min from the serosal side. Permeability of rumen and colon mucosa to (3)H-mannitol increased 6- and 5-fold, respectively, at acidic pH values of 4.5 and 5.5 and in the presence of 500 micro/mL of LPS. In contrast, LPS did not affect rumen and colon permeability at pH that ranged from 5.5 and 7.4. Translocation of LPS across the rumen and colon mucosa of cattle was not pH dependent. The LPS translocated through these tissues if present at the mucosal side. In conclusion, the permeability of rumen and colon tissues to (3)H-mannitol increased in presence of LPS and under acidic pH, whereas LPS permeated through mucosal tissues independently of the pH of the perfusate. Further research is warranted to understand the mechanism(s) by which acidic pH of the rumen digesta and presence of LPS make rumen and colon tissues "leaky".

Repeated acidosis challenges and live yeast supplementation shape rumen microbiota and fermentations and modulate inflammatory status in sheep

“…In AC1, we also observed a high level of rumen LPS and histamine. Owing to lysis of Gram-negative bacteria under low pH, free LPS concentration can increase in the rumen and its translocation may occur across the rumen epithelium (Emmanuel et al, 2007). Histamine can be produced by Lactobacilli and/or Allisonella histaminiformans that have already been described to survive at low pH in the rumen of cattle (Garner et al, 2002).…”

Nutrition, microbiota, and endotoxin-related diseases in dairy cows

“…We demonstrated that LPS translocates across the rumen wall at a greater rate than across the colon wall, and this translocation was pH independent. On the other hand, it was observed that at acidic pH values of the perfusate there was an increase in the permeability of more than 5-to 6-fold through colon and rumen tissues, respectively, to large molecules such as 3 H-mannitol (Emmanuel et al, 2007).…”

“…The main source of endotoxin entrance into the bloodstream before parturition might be the gastrointestinal tract. Previous research demonstrated that DCs have a 3.3-fold greater prevalence of pathogenic E. coli strains in their colon than the healthy ones (Byrne et al, 2003), which indicates that colonic endotoxin might translocate into bloodstream in DC around parturition (Emmanuel et al, 2007). Other potential sources of endotoxin in the periparturient cow are the infected mammary gland (Wenz et al, 2001) and the uterine tissue (Dohmen et al, 2000).…”

“…In some individual herds, the incidence rate may rise up to 10% or even 20% of all postpartal cows (Dawson et al, 1992). An increasing number of investigators are suggesting that the atony of the abomasum observed during the disease may be related to presence of endotoxin in the plasma of sick cows (Fürll & Krüger, 1999;Poike & Fürll, 2000). Endotoxin has been suggested to inhibit the motility of the abomasal smooth muscle either directly or indirectly via the induction of hypocalcemia.…”

Prepartum and postpartum nutritional management to optimize fertility in high-yielding dairy cows in confined TMR systems

“…Ametaj et al (2005) found a strong relationship between blood indicators of inflammation (acute phase proteins, TNFα) and hepatic lipid accumulation in dairy cows. Emmanuel et al (2007 and demonstrated that increasing amounts of barley grain increased concentrations of endotoxin in rumen fluid, and at low rumen pH the transfer of endotoxin across the rumen epithelium was increased. Intermittent administration of endotoxin triggered metabolic and inflammatory responses typically associated with displaced abomasum and retained placenta (Zebeli et al, 2011).…”