Screening of Caesalpinia bonduc leaves for antipsoriatic activity

Abstract

Leaves of Caesalpinia bonduc (L.) Roxb. (Caesalpiniaceae) have been used by traditional Siddha healer of Malabar region for psoriasis treatment. To evaluate the Caesalpinia bonduc decoction (CBD), Caesalpinia bonduc hydroalcoholic extract (CBHA) for antipsoriatic activity. Mouse tail test for psoriasis was used for the evaluation of antipsoriatic activity. Extracts were tested at a dose of 500 mg/kg b.w. and fractions at 250 mg/kg b.w. in Swiss albino mice. Parameters studied in the mouse tail test were changes in epidermal thickness and percentage orthokeratotic values. In vitro antiproliferant assay on HaCaT cell lines and in vitro lipoxygenase inhibition were also carried out. Butanol fraction of Caesalpinia bonduc hydroalcoholic extract (CBHAB) and water fraction of Caesalpinia bonduc hydroalcoholic extract (CBHAW) produced significant orthokeratosis (p<0.001). In relative epidermal thickness, a significant (p<0.05) reduction with respect to control was observed in groups treated with retinoic acid, CBD, butanol fraction of Caesalpinia bonduc decoction (CBDB), water fraction of Caesalpinia bonduc hydroalcoholic extract (CBHAW). Maximum antiproliferant activity was shown by CBHA (IC(50), 77.5±12.7 μg/ml). In lipoxygenase inhibition assay, water fraction of Caesalpinia bonduc decoction (CBDW) showed maximum activity with an IC(50) value of 164.71±4.57 μg/ml. Among all the tested samples only CBHAW showed good activity in the mouse tail test, antiproliferant activity in HaCaT cells and lipoxygenase inhibition assay. Other extracts and fractions showed varying degrees of activity. The present study supports the traditional use of Caesalpinia bonduc leaves for psoriasis treatment.