Anti-Psoriatic Activity of Flavonoids from the Bark of Givotia rottleriformis Griff. Ex Wight.

Givotia rottleriformis has been used in the indigenous systems of medicine for the treatment of inflammatory diseases like rheumatism and psoriasis. In order to evaluate this information, antipsoriatic activity of three flavonoids isolated from the ethanol extract of the bark of Givotia rottleriformis were investigated using in-vitro and in-vivo model, namely Rutin (I), Luteolin-7-O-β-D-Glucuronide (II) and Kaempferol 3-O-[2-O-(6-O-feruloyl)-β-D-glucopyranosyl]-β-D-galactopyranoside (III). The extract was standardized by HPLC using chemical markers. In vitro antiproliferant assay of the ethanol extract and isolated flavonoids were done on HaCaT cell lines. Mouse tail test was used for the evaluation of antipsoriatic activity of ethanol extract (100, 200 and 400 mg/kg b.w.) and bioactive flavonoids (50 mg/kg b.w.) in Swiss albino mice. In the HPLC analysis, 4 flavonoids were identified by comparison with retention time of standard marker viz., Rutin, Quercetin, Kaempferol and Luteolin. Maximum antiproliferant activity was shown by isolated flavonoids II and III (56.50±12.84μg/ml and 76.50±8.60μg/ml). In mouse tail model, a significant reduction in epidermal thickness with respect to control was observed in groups treated with isolated flavonoids II, III and significant orthokeratosis was observed in groups treated with ethanol extract (200 and 400 mg/kg) and isolated flavonoids II, III.