Ten 2-substituted
quinoline alkaloids isolated from a plant used for treatment of New World
cutaneous leishmaniasis have antileishmanial in vitro activities against the extracellular forms of Leishmania spp. BALB/c mice infected with Leishmania amazonensis PH8 or
H-142 or Leishmania venezuelensis were treated 1 day after the
parasitic infection with a
quinoline alkaloid (100 mg/kg of
body weight per day) or with reference
drug N-methylglucamine antimonate (
Glucantime) (56 mg of pentavalent
antimony [Sbv] per kg per day) for 14 days. Lesion development was the criterium used to assess disease severity. Two three-
carbon chain
quinolines [2-n-propylquinoline and 2-(1',2'-trans-epoxypropyl)quinoline (chimanine D)] were more potent than
N-methylglucamine antimonate against L. amazonensis PH8, and five
quinoline alkaloids [2-(3,4-methylenedioxyphenylethyl)
quinoline, cusparine, 2-(3,4-dimethoxyphenylethyl)quinoline, 2-(E)-prop-1'-enylquinoline (chimanine B), and
skimmianine] were as effective as the reference
drug. Single treatment near the site of
infection, 14 days after
infection with L. amazonensis, with
2-n-propylquinoline or chimanine B reduced the severity of lesions but less notably than
N-methylglucamine antimonate.
2-n-Propylquinoline exhibited significant activity against the virulent strain L. venezuelensis. The active products did not show any apparent toxicities during the experiment. This study is, to our knowledge, the first to show the activity of 2-substituted
quinoline alkaloids for experimental treatment of New World
cutaneous leishmaniasis. Further investigations of these compounds might yet prove helpful for the development of new antileishmanial drugs.