Antileishmanial Activity of Three Saponins Isolated from Ivy, α-Hederin, β-Hederin and Hederacolchiside A₁, as Compared to Their Action on Mammalian Cells Cultured in Vitro

Abstract

The in vitro antileishmanial activity of three saponins isolated from ivy, alpha-hederin, beta-hederin and hederacolchiside A1, was investigated on Leishmania infantum. The assessment of possible targets (membrane integrity, membrane potential, DNA synthesis and protein content) was performed in both Leishmania promastigotes and human monocytes (THP1 cells). Results observed in Leishmania showed that the saponins exhibited a strong antiproliferative activity on all stages of development of the parasite by altering membrane integrity and potential: hederacolchiside A1 appeared to be the most active compound against both promastigotes and amastigotes. Results observed in THP1 cells demonstrated that the saponins exerted also a potent antiproliferative activity against human monocytes, by producing a significant DNA synthesis inhibition. The ratio between antileishmanial activity on amastigotes and toxicity to human cells suggested that the saponins could be considered as possible antileishmanial drugs.

Tectorigenin, an Isoflavone of Pueraria thunbergiana BENTH., Induces Differentiation and Apoptosis in Human Promyelocytic Leukemia HL-60 Cells.

“…Glycosides were inactive however; as previously reported most cytotoxic natural compounds do not belong to glycosides except for the cytotoxic saponin acting on cellular membranes. 15,16) In general, hydrophilic compounds with sugar moieties are hardly permeable to the cellular membranes. 17) Tectorigenin induced differentiation into granulocytes and/or monocytes/macrophages, as assessed by NBT reduction, latex beads phagocytic activity and CD14 and CD66b antigen expression, and by apoptosis, as assessed by increase in hypodiploid population and DNA ladder formation, of human promyelocytic leukemia HL-60 cells less effectively than genistein.…”

Adjuvant effects of saponins on animal immune responses

“…Saponin not only has stimulatory effects on the components of specific immunity, but also presents some non-specific immune reactions such as inflammation (de Oliveira et al, 2001;Haridas et al, 2001) and monocyte proliferation (Delmas et al, 2000;Yui et al, 2001). …”

Triterpenoid Saponins from Leaves of Hedera pastuchowii

“…4) The antileishmanial activity of a-hederin, b-hederin and hederacolchiside A 1 in association with Pentamidine and Amphotericin B showed that subtoxic concentrations of these saponins enhance the efficiency of Pentamidine and Amphotericin B on the promastigote and the amastigote forms of the parasites. 5,6) Hederacolchiside A 1 was strongly cytotoxic against malignant melanoma M 4 Beu (IC 50 ϭ5 mM). 7) This saponin exhibits a preferential cytotoxicity on pigmented melanoma cells and interacts specifically with melanin.…”