Antitrypanosomal Activities and Mechanisms of Action of Novel Tetracyclic Iridoids from Morinda lucida Benth

Antimicrob Agents Chemother. 2016 May 23;60(6):3283-90. doi: 10.1128/AAC.01916-15. Print 2016 Jun.

Abstract

Trypanosoma brucei parasites are kinetoplastid protozoa that devastate the health and economic well-being of millions of people in Africa through the disease human African trypanosomiasis (HAT). New chemotherapy has been eagerly awaited due to severe side effects and the drug resistance issues plaguing current drugs. Recently, there has been an emphasis on the use of medicinal plants worldwide. Morinda lucida Benth. is a popular medicinal plant widely distributed in Africa, and several research groups have reported on the antiprotozoal activities of this plant. In this study, we identified three novel tetracyclic iridoids, molucidin, ML-2-3, and ML-F52, from the CHCl3 fraction of M. lucida leaves, which possess activity against the GUTat 3.1 strain of T. brucei brucei The 50% inhibitory concentrations (IC50) of molucidin, ML-2-3, and ML-F52 were 1.27 μM, 3.75 μM, and 0.43 μM, respectively. ML-2-3 and ML-F52 suppressed the expression of paraflagellum rod protein subunit 2, PFR-2, and caused cell cycle alteration, which preceded apoptosis induction in the bloodstream form of Trypanosoma parasites. Novel tetracyclic iridoids may be promising lead compounds for the development of new chemotherapies for African trypanosomal infections in humans and animals.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antiprotozoal Agents / chemistry
  • Antiprotozoal Agents / pharmacology*
  • Apoptosis / drug effects
  • Cell Cycle / drug effects
  • Humans
  • Inhibitory Concentration 50
  • Iridoids / chemistry
  • Iridoids / pharmacology*
  • Morinda / chemistry*
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology
  • Plants, Medicinal / chemistry*
  • Trypanocidal Agents / chemistry
  • Trypanocidal Agents / pharmacology*
  • Trypanosoma / drug effects
  • Trypanosoma / pathogenicity
  • Trypanosomiasis, African / physiopathology

Substances

  • Antiprotozoal Agents
  • Iridoids
  • Plant Extracts
  • Trypanocidal Agents