Anti-leishmanial,immunomodulatory and anti-oxidative activity of quercetin against cutaneous leishmaniasis caused by Leishmania major

Objective:To evaluate the in vitro and in vivo efficacy of quercetin and its immunomodulatory and anti-oxidative activity against Leishmania major(L.major).Methods:L.major promastigotes and amastigotes were incubated with different concentrations of quercetin to estimate EC_(50).For in vivo study,the base of tails of mice was infected with L.major.After developing ulcers in the inoculation site,mice were treated with 50 mg/kg quercetin orally for 28 consecutive days.The wound-healing potential of quercetin was evaluated by histopathological analysis of tissue sections stained by hematoxylin and eosin as well as Masson's trichrome.In addition,the levels of tumor necrosis factor-α,interleukin-6,malondialdehyde,and adiponectin,the ferric reducing ability of plasma,as well as superoxide dismutase and glutathione peroxidase activities were measured.Results:The EC_(50)values of quercetin against L.major promastigotes and intracellular amastigotes were 0.27 and 0.85μM,respectively.Histopathological analysis showed that fewer inflammatory cells,more fibroblasts,and more collagen deposition were observed in tissue sections of quercetin-treated mice.In addition,treatment with quercetin markedly increased glutathione peroxidase activity,the ferric reducing ability of plasma and adiponectin levels while decreasing malondialdehyde,interleukin-6,and tumor necrosis factor-αlevels.Conclusions:Quercetin shows anti-leishmanial activity,immunomodulatory,anti-oxidative,and anti-inflammatory effects.Therefore,it may be further explored as an effective drug in treating leishmaniasis.