The Effects of Darbepoetin on Peritoneal Fibrosis Induced by Chemical Peritonitis and on Peritoneal Tissue Mmp-2 and Timp-2 Levels in Rats

Abstract

The aim of this study is to assess the influence of darbepoetin on the development of peritoneal fibrosis in rats induced by Chlorhexidine gluconate (0.1%) and ethanol (15%) and to determine the effect on peritoneal tissue levels of MMP–2 and TIMP–2, possible important factors in progression of peritoneal fibrosis. Twenty-four female Wistar albino rats were divided into three groups. The first group (CH group) received 3 ml/200g daily intraperitoneal injections of Chlorhexidine gluconate (0.1%) and ethanol (15%) dissolved in saline to induce chemical peritonitis; group 2 (ESA group) received 3 ml/200g daily injections of Chlorhexidine gluconate (0.1%) and ethanol (15%) dissolved in saline and also darbepoetin 12.5 microgr/ per kilogram/ day subcutaneously on the first and seventh days; group 3 (Control group) received intraperitoneal 0.9% saline (3 ml/200g/d) through the right lower quadrant by 21 gauge needle. The study duration was fourteen days. On the fifteenth day rats were sacrificed, parietal peritoneum samples were obtained from the left anterior abdominal wall. Pathological samples were examined using Hematoxyline & Eosin (HE) stains. The thickness, vasculpathy, and inflammation were determined by light microscopy. MMP-2 and TIMP-2 were studied immunohistochemically by monoclonal antibody staining. The activity of MMP-2 on peritoneal tissue was studied by gelatin zymography and TIMP–2 protein level was analysed by ELISA, biochemically. The decrease in thickness of parietal peritoneum in group ESA was statistically significant when compared to CH group (p<0.05). Inflammation scores, and vascularization score surfaces were not statistically different between these groups (p>0.05). Immunohistochemically, darbepoetin was shown to decrease MMP-2 expression on parietal peritoneum in CH group (p<0.05), but had no effect on TIMP-2 (p>0.05). Biochemically the ratio of active MMP–2 to proMMP–2 was more significantly increased in the ESA group than in the CH group (p<0.001), however, TIMP- 2 levels in both groups were decreased compared to the control group (p<0.05). Darbepoetin histopathologically reduced peritoneal fibrosis induced by Chlorhexidine gluconate. We can suggest that Darbepoetin does not cause peritoneal fibrosis and may prevent peritoneal fibrosis in rats possibly related to an effect on MMP-2 expression. Further research regarding the utility and dosage should be considered.