Comparative Study of Anti-Inflammatory Activity of Rosuvastatin With That of Aspirin in Albino Rats

Abstract

BACKGROUND Statins are HMG-CoA (3-hydroxy-3-methylglutaryl-coenzyme A) reductase inhibitors well known for their hypolipidemic action. More recently, there has been an increased interest in pleiotropic effects of statins like anti-inflammatory action that occurs independent of their lipid lowering effect. Statins exert anti-inflammatory action by preventing the isoprenylation of Rho proteins, a family of small G proteins and subsequent disruption of their functions. Hence, the present study was planned to compare the anti-inflammatory effect of rosuvastatin with that of aspirin on acute inflammation, so that it could be utilised in acute inflammatory conditions as an adjuvant or as a monotherapy avoiding adverse effects of commonly used antiinflammatory agents like NSAIDS (nonsteroidal anti-inflammatory drugs). The aim of the study is to compare anti-inflammatory effect of rosuvastatin with that of aspirin on carrageenan-induced inflammation in albino rats. MATERIALS AND METHODS 18 adult albino rats weighing between 100-150 g of either sex were divided into 3 groups. Control, Standard and test receiving oral normal saline (2 mL/kg), aspirin (100 mg/kg) and rosuvastatin (5 mg/kg) drug solutions, respectively. Acute inflammation model of carrageenan-induced paw oedema was used as tool. An hour after the administration of the drugs to each group, paw oedema was induced with intradermal injection of 0.1 mL of carrageenan (1%) into the plantar surface of the right hind paw of each rat. Volume of inflamed paw was determined using a plethysmometer immediately and also at 30, 60, 120 and 180 minutes after injection. Finally, mean paw volumes at different time intervals were calculated and percentage inhibition of paw oedema with standard and test drugs were determined. RESULTS Data was analysed using by Analysis of Variance (ANOVA). Results showed that rosuvastatin has statistically significant (P<0.05) anti-inflammatory action reflected by percentage inhibition of paw oedema at different time intervals when compared to control. The antiinflammatory action of rosuvastatin was found intermediate to that of standard (aspirin) and control (normal saline). CONCLUSION From this study, it is evident that statins does have anti-inflammatory action. This study results also indicate that statins antiinflammatory effect is more in late phase of acute inflammation probably due to inhibition of new synthesis of proinflammatory agents. NSAIDS and statins, both of them act via different mechanisms and their actions could be additive. Hence, rosuvastatin could be a promising adjuvant to existing anti-inflammatory drugs in acute inflammatory condition particularly with hyperlipidaemias.