Rosuvastatin reduces rat intestinal ischemia-reperfusion injury associated with the preservation of endothelial nitric oxide synthase protein

Abstract

Aim: To investigate the protective effect of rosuvastatin on ischemia-reperfusion (I-R)-induced small intestinal injury and inflammation in rats, and to determine the effect of this agent on the expression of endothelial nitric oxide synthase (eNOS) protein.

Methods: Intestinal damage was induced in male Sprague-Dawley rats by clamping both the superior mesenteric artery and the celiac trunk for 30 min, followed by reperfusion for 60 min. Rosuvastatin dissolved in physiological saline was administered intraperitoneally 60 min before ischemia. The severity of the intestinal mucosal injury and inflammation were evaluated by several biochemical markers, as well as by histological findings. The protein levels of eNOS were determined by Western blot.

Results: The levels of both intraluminal hemoglobin and protein, as indices of mucosal damage, were significantly increased in the I-R group compared with those in the sham-operated group. These increases, however, were significantly inhibited by treatment with rosuvastatin in a dose-dependent manner. The protective effects of rosuvastatin were also confirmed by histological findings. Exposure of the small intestine to I-R resulted in mucosal inflammation characterized by significant increases in thiobarbituric acid-reactive substances, tissue-associated myeloperoxidase activity, and the mucosal contents of rat cytokine-induced neutrophil chemoattractant-1 (CINC-1) and tumor necrosis factor-alpha (TNF-alpha). These increases in inflammatory parameters after I-R were significantly inhibited by pretreatment with rosuvastatin at a dose of 10 mg/kg. Furthermore, mRNA expression of CINC-1 and TNF-alpha was increased after I-R, and this increase was also inhibited by rosuvastatin. The mucosal protein levels of eNOS decreased during I-R, but were preserved in rats treated with rosuvastatin.

Conclusion: Rosuvastatin inhibits rat intestinal injury and inflammation induced by I-R, and its protection is associated with the preservation of eNOS protein.

Figure 1

Dose-response of rosuvastatin on acute intestinal I-R injury in rats (mean ±SE). A: Intraluminal protein; B: Hemoglobin. ^bP<0.01 vs Sham, ^aP<0.05, ^dP<0.01 vs Vehicle + I-R.

Figure 2

Histological appearance of the small intestine in rats (HE ×20). N: Sham. C: I-R. R: I-R plus rosuvastatin.

Figure 3

Effects of rosuvastatin on lipid peroxide concentrations and neutrophil accumulation in the intestinal mucosa of rats treated with I-R (mean±SE). A: TBA-reactive substance; B: Myeloperoxidase activity. ^bP<0.01 vs Sham, ^aP<0.05 vs Vehicle + I-R.

Figure 4

Effects of rosuvastatin on the intestinal CINC-1 and TNF-α after I-R in rats (mean+SE). A: CINC-1; B: TNF-α. ^bP<0.01 vs Sham, ^aP<0.05 vs Vehicle + I-R.

Figure 5

Effects of rosuvastatin on the expression of CINC-1 and TNF-α mRNA in the intestinal mucosa after I-R in rats.

Figure 6

Effect of rosuvastatin on eNOS protein expression during I-R. ^aP<0.05 vs Sham, ^cP<0.05 vs Vehicle + I-R.