Phloroglucinol derivatives from Hypericum species trigger mitochondrial dysfunction in Leishmania amazonensis

Area of Science:

• Natural Product Chemistry
• Parasitology
• Drug Discovery

Background:

• Leishmaniasis remains a significant global health concern, necessitating novel therapeutic strategies.
• Plant-derived bioactive molecules offer a promising avenue for developing new anti-leishmaniasis drugs.

Purpose of the Study:

• To evaluate the leishmanicidal activity of cariphenone A, isouliginosin B, and uliginosin B from Hypericum species against Leishmania amazonensis.
• To assess the cytotoxicity and selectivity index of these compounds against mammalian cells.

Main Methods:

• In vitro evaluation of anti-promastigote and anti-amastigote activity of compounds 1-3.
• Assessment of synergistic interactions between compound combinations.
• Cytotoxicity assays using MTT method and hemolysis assay on macrophages and erythrocytes.

Main Results:

• Compounds 1-3 demonstrated significant leishmanicidal activity against Leishmania amazonensis promastigotes with IC50 values ranging from 10.5 to 17.5 µm.
• Synergistic anti-promastigote effects were observed for combinations of compounds 1 and 2, and 2 and 3.
• The compounds exhibited low cytotoxicity towards mammalian cells, indicating a high selectivity index.

Conclusions:

• Cariphenone A, isouliginosin B, and uliginosin B possess potent leishmanicidal properties.
• These natural compounds induce oxidative stress in Leishmania parasites, leading to cell death.
• The favorable safety profile and efficacy suggest these compounds are promising candidates for leishmaniasis drug development.