In-vitro and In-vivo Activities of Phenolic Compounds A gainst Cutaneous Leishmaniasis

Phenolic compounds (PCs) are well-known phytochemicals found in plants that have been studied for their pharmacological properties. In particular, the potentialities of PCs as anti-leishmanial agents have been reported. In the present study, we evaluated 10 PCs for in-vitro anti-leishmanial activity and two PCs, p-coumaric acid (CA) and gentisic acid (GA) against experimental cutaneous leishmaniasis in BALB/c mice infected with L. amazonensis. Five doses of each pure compound were administrated every 4 days at 30 mg/kg by intralesional route and disease progression was compared with animals treated with glucantime (GTM). All tested compounds inhibited intracellular amastigotes growing, with IC50 values between 4.4 and 25.5 µM. Treated animals with GA showed a significant reduction (p < 0.05) in the size of lesion and parasite burden compared with animals treated with CA, GTM and untreated mice. The treatment with CA caused reduction of lesion size (p < 0.05) compared with GTM and control mice, but had the same (p > 0.05) parasite burden as control and GTM treated animals. The present findings established that CA and GA have significant anti-leishmanial effects. Further experiments on formulation design, mechanism of action and probably anti-inflammatory / immune-modulator activity of GA could be encouraged.