Evaluation of the aqueous extract of Rotula aquatica roots in acute and chronic inflammatory conditions in rats

Abstract

The aqueous extract of Rotula aquatica Lour (Boraginaceae) roots was investigated for its anti-inflammatory potential in acute and chronic inflammatory conditions in rats. The aqueous extract of the plant at doses 50, 100, and 200 mg kg⁻¹, p.o., were screened against carrageenan-induced rat paw edema, cotton pellet-induced granuloma as well as crystal-induced inflammation in rats. The IL-6 levels in the exudates formed due to crystal-induced inflammation were also determined. The extract exhibited a statistically significant (p < 0.05) inhibition of rat paw edema as compared to the control group. With respect to crystal-induced inflammation, the extract demonstrated a statistically significant (p < 0.05) reduction in the neutrophil and monocyte count in the inflammatory exudates compared to the control group. The extract at a dose of 200 mg kg⁻¹ also effectively inhibited IL-6 levels. The extract exhibited a statistically significant (p < 0.05) reduction in the weight of cotton pellet-induced granuloma at the doses of 100 and 200 mg kg⁻¹ employed in the study compared to the control group. Supportive studies included determination of in vitro antioxidant potential of the extract by DPPH free radical scavenging method. The results revealed that the extract possesses appreciable anti-oxidant activity (IC₅₀ = 11.07 μg mL⁻¹). Collectively, the results indicated the extract of R. aquatica to have a potentially beneficial effect in relieving inflammation and providing a platform for the development of plant drugs for crystal-induced arthropathy.

Keywords::

• Rotula aquatica
• carrageenan
• cotton pellet granuloma
• anti-inflammatory
• crystal-induced inflammation
• IL-6

Acknowledgement

The authors are thankful to the Department of Biotechnology (DBT), New Delhi, India for providing financial assistance.