Anti-inflammatory effect of Heliotropium indicum Linn on lipopolysaccharide-induced uveitis in New Zealand white rabbits

AIM: To investigate the anti-inflammatory effect of an aqueous whole plant extract of Heliotropium indicum(HIE) on endotoxin-induced uveitis in New Zealand white rabbits.·METHODS: Clinical signs of uveitis including flares,iris hyperemia and miosis, were sought for and scored in1.0 mg/kg lipopolysaccharide(LPS)-induced uveitic rabbits treated orally with HIE(30-300 mg/kg),prednisolone(30 mg/kg), or normal saline(10 m L/kg). The number of polymorphonuclear neutrophils infiltrating, the protein concentration, as well as levels of tumor necrosis factor-α(TNF-α), prostaglandin E2(PGE2), and monocyte chemmoattrant protein-1(MCP-1) in the aqueous humor after the various treatments were also determined. A histopathological study of the anterior uveal was performed.· RESULTS: The extract and prednisolone-treatment significantly reduced(P ≤0.001) both the clinical scores of inflammation(1.0-1.8 compared to 4.40 ±0.40 in the normal saline-treated rabbits) and inflammatory cells infiltration. The level of protein, and the concentrationsof TNF-α, PGE2 and MCP-1 in the aqueous humor were also significantly reduced(P ≤0.001). Histopathological studies showed normal uveal morphology in the HIE and prednisolone-treated rabbits while normal saline-treated rabbits showed marked infiltration of inflammatory cells.· CONCLUSION: The HIE exhibits anti-inflammatory effect on LPS-induced uveitis possibly by reducing the production of pro-inflammatory mediators.