Fig 1.
Effect of CORM-2 on CLP-induced intestinal inflammation.
Typical images of H&E stained intestinal sections from sham (A), CLP (B) rats or CLP rats with CORM-2 (C) or iCORM-2 (D) treatment. Severe inflammation (ulceration, hemorrhage and epithelial loss) was found in CLP rat (B) and CLP rats treated with iCORM (D). These changes were alleviated CLP rats treated with CORM-2 (C). These differences were semi-quantified using Chiu score system of mucosal injury by 2 investigators (E). Data are shown as means±SD. aP<0.05, compare to Sham rats; bP<0.05, compare to CLP rats; cP<0.05, compare to CLP rats treated with iCORM-2. Bar = 200μm.
Fig 2.
Tight junctions of intestinal epithelium were revealed by transmission electronic microscopy.
Typical images from Sham rats (A), CLP rats (B), CLP rats treated with CORM-2 (C) or iCORM-2 (D). Black arrows indicate epithelial cell surface microvilli and white arrows indicate tight junctions. Magnification × 60000.
Fig 3.
Effects of CLP and CORM-2 on tight junction proteins and intestinal epithelial barriers.
Anti- ZO-1, claudin-1 or occludin were used to stain the sections of ileum from different groups of rats. Typical images were presented. Arrows indicate the highlighted intestinal epithelial barriers. Scale bars = 100μm.
Fig 4.
Effects of CLP and CORM-2 on the expression levels of tight junction proteins.
Ileum from different groups of rats were collected and homogenized. The tissue lysates were subjected to Western blotting analysis using specific antibodies for ZO-1, claudin-1 or occludin with β-actin as an endogenous control. Typical Western blots are presented (A). The band intensity was quantified using densitometry. The means±SDs of ZO-1/β-actin ratios (B); claudin-1/β-actin ratios (C); and occludin/β-actin ratios (D) from different groups of rats are presented. aP < 0.05 compared to Sham rats; bP < 0.05 compared to CLP rats; cP < 0.05 compared to CLP rats treated with CORM-2.
Fig 5.
Effects of CLP and CORM-2 on MLC phosphorylation in rat ileum.
The lysates of ileum from different groups of rats were subjected to Western blotting analysis with anti-MLC and phosphorylation-specific antibody for p-MLC. Typical Western blots and Means±SD of the ratios of p-MLC/MLCcalculated based on the densities of bands on Western blots from four groups are presented. (A): Time course of MLC phosphorylation in CLP (C) and CORM-2-treated (T) CLP rats (5 rats each time point per group) aP < 0.05 compared to CLP group. (B) The MLC phosphorylation levels at 24 h of each experimental group. aP < 0.05 compared to Sham rats; bP < 0.05 compared to CLP rats; cP < 0.05 compared to CLP rats treated with CORM-2.
Fig 6.
Effects of CORM-2 on CLP-induced proinflammatory cytokine release.
Blood was taken from portal vein at 24h after sepsis induction by CLP. Concentrations of TNF-α and IL-1β were measured using ELISA kits. Means±SD from 10 rats per group are presented. aP<0.05, compare to Sham rats; bP<0.05, compare to CLP rats; cP<0.05, compare to CLP rats treated with iCORM-2.
Fig 7.
Effects of CORM-2 on intestinal permeability and survival of CLP rats.
FD-4 was injected into a loop of intestine (See methods) and 30min late, the levels of FD-4 in portal vein were measured to reflect intestinal epithelial permeability changes. Means±SD from 5 rats each group are presented (A). Separated rats for each group (12 rats per group) were used to determine 72h mortality rates. Kaplan-Meier survival curves are shown (B). aP < 0.05 compared to Sham rats; bP < 0.05 compared to CLP rats; cP < 0.05 compared to CLP rats treated with CORM-2.