Background and aim Serum calprotectin is elevated in patients with inflammatory bowel disease (IBD). Whether it correlates other markers of disease activity is unknown. The aim of this study was to correlate serum calprotectin with biochemical and histological measures of intestinal inflammation. Materials and methods TNBS colitis was induced in wistar rats, and serial blood samples were collected at 0, 3, and 12 days. Animals were subsequently sacrificed for pathological evaluation at day 12. Serum calprotectin and cytokines were measured by ELISA. Pathologic changes were classified at the macroscopic and microscopic levels. Results TNBS colitis induced elevated serum calprotectin, TNF and IL-6 within 24 h. Levels of serum calprotectin remained elevated in parallel to persistence of loose stool and weight loss to day 12. Serum calprotectin levels correlated with serum levels of TNF-α and IL6 (p < 0.001), but not CRP. Animals with liquid stool had significantly higher levels of serum calprotectin than control animals. There was a correlation between macroscopic colitis scores, and levels of serum calprotectin. Conclusion Serum calprotectin levels correlate with biochemical and histological markers of inflammation in TNBS colitis. This biomarker may have potential for diagnostic use in patients with IBD.

Eicosapentaenoic acid (EPA) can induce a shift in prostaglandin and leukotriene synthesis. The effects of EPA supplementation of the diet on the progression of chronic renal failure (CRF) were evaluated in a model of ⁵/₆ renal mass ablation in rats. After 30 or 60 days of CRF, elevation in single-nephron glomerular filtration rate due to an increase in glomerular plasma flow and hydraulic pressure was observed. These hemodynamic alterations were followed by a rise in proteinuria and glomerular sclerosis. EPA treatment for 30 or 60 days did not substantially modify the hemodynamic or morphological profiles induced by renal mass ablation. In the present non-immune model of CRF, preglomerular vasodilation with glomerular hyperperfusion and hypertension were responsible, at least in part, for the presence of proteinuria and glomerular sclerosis. No additional vasodilation was observed in the present model of CRF, and, thus, hemodynamic effects induced by EPA did not modify renal damage, in contrast to the EPA effects observed in immune-mediated models of CRF.