N-Acetylglucosamine Reduces Inflammatory Response during Acute Peritonitis in Uremic Rats

Abstract

Background: Peritoneal dialysis (PD) induces intraperitoneal inflammation and that process may be uremia. The goal of this study is to evaluate the effect of ure- mia on the kinetics of peritonitis and furthermore test the anti-inflammatory potential of N-acetylglucosamine (NAG) in a uremic environment. Methods: Experiments were performed on healthy Wistar rats and on animals with impaired renal function. Acute PD was performed in all animals with dialysis fluid containing either glucose (GLU) or NAG as osmotic solutes. Peritonitis was induced by addition of lipopolysaccharide from Escherichia coli (LPS) to the dialysis fluid. Transperitoneal transport of water and solutes as well as intraperitoneal and systemic inflammation were evaluated. Results: Uremia reduces peritoneal permeability to total protein during peritonitis (–33% vs. control, p < 0.001) and increases net ultrafiltration (+2.5 ± 2.2 vs. –2.7 ± 3.2 ml in control, p < 0.001). In uremic rats with peritonitis, reduced dialysate levels of the following inflammatory mediators were detected as compared to healthy animals: MCP-1 (–15%, p < 0.01); IL-1β (–53%, p < 0.001), and elastase (–28%, p < 0.02). In the serum of uremic rats, the increase in TNFα and MCP-1 concentrations was smaller than in control rats: –44% (p < 0.02) and –39% (p < 0.001), respectively. NAG used as an osmotic solute in rats with preserved renal function decreases intraperitoneal and systemic inflammation during acute peritonitis. Drained dialysate volume was increased in the NAG group by 32% (p < 0.001) and transperitoneal loss of protein was reduced by 21% (p < 0.002). When NAG was used as the osmotic solute instead of GLU, intraperitoneal inflammation in uremic animals was further reduced: TNFα (–40%, p < 0.05); IL-1β (–49%, p < 0.005); MCP-1 (–21%, p < 0.005). The presence of NAG also reduced the increased blood level of IL-1β (–47%,p < 0.02) and MCP-1 (–36%, p < 0.02). Conclusions: Intensity of acute peritonitis is reduced during uremia. NAG exerts a systemic and peritoneal anti-inflammatory action under conditions of uremia that confirms the potential use of this compound as an osmotic agent in the PD fluids that also decreases inflammation.