ABSTRACT
Treatment of leishmaniasis by chemotherapy remains a challenge because of limited efficacy, toxic side effects, and drug resistance. We previously reported that synthetic flavonoid dimers have potent antipromastigote and antiamastigote activity against
Leishmania donovani
, the causative agent of visceral leishmaniasis. Here, we further investigate their leishmanicidal activities against cutaneous
Leishmania
species. One of the flavonoid dimers (compound 39) has marked antipromastigote (50% inhibitory concentrations [IC
50
s], 0.19 to 0.69 μM) and antiamastigote (IC
50
s, 0.17 to 2.2 μM) activities toward different species of
Leishmania
that cause cutaneous leishmaniasis, including
Leishmania amazonensis
,
Leishmania braziliensis
,
Leishmania tropica
, and
Leishmania major
. Compound 39 is not toxic to peritoneal elicited macrophages, with IC
50
values higher than 88 μM. In the mouse model of cutaneous leishmaniasis induced by subcutaneous inoculation of
L. amazonensis
in mouse footpads, intralesional administration of 2.5 mg/kg of body weight of compound 39.HCl can reduce footpad thickness by 36%, compared with that of controls values. The amastigote load in the lesions was reduced 20-fold. The present study suggests that flavonoid dimer 39 represents a new class of safe and effective leishmanicidal agent against visceral and cutaneous leishmaniasis.
摘要
由于疗效有限、毒副作用和耐药性,化疗治疗利什曼病仍是一项挑战。我们以前曾报道过,合成黄酮二聚体具有强效的抗原生动物和抗非原生动物活性。
唐氏利什曼病
的活性。在此,我们进一步研究了它们对皮肤利什曼病的杀利什曼活性。
利什曼
种的杀利什曼活性。其中一种黄酮类二聚体(化合物 39)具有明显的抗原体作用(50% 抑制浓度 [IC
50
s],0.19 至 0.69 μM)和抗原生动物(IC
50
s,0.17 至 2.2 μM)的活性。
利什曼病
的活性,其中包括
亚马逊利什曼病
,
巴西利什曼病
,
热带利什曼病
和
大利什曼原虫
.化合物 39 对腹膜诱发的巨噬细胞无毒性,其 IC
50
值高于 88 μM。在通过皮下注射亚马逊利什曼原虫诱导的皮肤利什曼病小鼠模型中,化合物 39 对腹膜诱导的巨噬细胞无毒性,IC 50 值高于 88 μM。
L. amazonensis
在小鼠脚垫皮下接种亚马逊嗜血杆菌诱发的皮肤利什曼病模型中,与对照组相比,穴内注射 2.5 毫克/千克体重的化合物 39.盐酸盐可使脚垫厚度减少 36%。病变部位的变形虫数量减少了 20 倍。本研究表明,类黄酮二聚体 39 是一种安全有效的利什曼杀虫新药,可用于防治内脏和皮肤利什曼病。