Procainamide-SAHA Fused Inhibitors of hHDAC6 Tackle Multidrug-Resistant Malaria Parasites

J Med Chem. 2021 Jul 22;64(14):10403-10417. doi: 10.1021/acs.jmedchem.1c00821. Epub 2021 Jun 29.

Abstract

Epigenetic post-translational modifications are essential for human malaria parasite survival and progression through its life cycle. Here, we present new functionalized suberoylanilide hydroxamic acid (SAHA) derivatives that chemically combine the pan-histone deacetylase inhibitor SAHA with the DNA methyltransferase inhibitor procainamide. A three- or four-step chemical synthesis was designed starting from cheap raw materials. Compared to the single drugs, the combined molecules showed a superior activity in Plasmodium and a potent inhibition against human HDAC6, exerting no cytotoxicity in human cell lines. These new compounds are fully active in multidrug-resistant Plasmodium falciparum Cambodian isolates. They target transmission of the parasite by inducing irreversible morphological changes in gametocytes and inhibiting exflagellation. The compounds are slow-acting and have an additive antimalarial effect in combination with fast-acting epidrugs and dihydroartemisinin. The lead compound decreases parasitemia in mice in a severe malaria model. Taken together, this novel fused molecule offers an affordable alternative to current failing antimalarial therapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antimalarials / chemical synthesis
  • Antimalarials / chemistry
  • Antimalarials / pharmacology*
  • Dose-Response Relationship, Drug
  • Drug Resistance, Multiple / drug effects
  • Histone Deacetylase 6 / antagonists & inhibitors*
  • Histone Deacetylase 6 / metabolism
  • Histone Deacetylase Inhibitors / chemical synthesis
  • Histone Deacetylase Inhibitors / chemistry
  • Histone Deacetylase Inhibitors / pharmacology*
  • Hydroxamic Acids / chemistry
  • Hydroxamic Acids / pharmacology*
  • Malaria, Falciparum / drug therapy*
  • Molecular Structure
  • Plasmodium falciparum / drug effects*
  • Procainamide / chemistry
  • Procainamide / pharmacology*
  • Structure-Activity Relationship

Substances

  • Antimalarials
  • Histone Deacetylase Inhibitors
  • Hydroxamic Acids
  • HDAC6 protein, human
  • Histone Deacetylase 6
  • Procainamide