An Update on African Trypanocide Pharmaceutics and Resistance

Area of Science:

• Veterinary Parasitology
• Medical Parasitology
• Drug Discovery

Background:

• African trypanosomiasis, caused by Trypanosoma species, presents distinct forms in animals (AAT) and humans (HAT).
• Existing trypanocidal drugs like suramin, melarsoprol, and eflornithine exhibit specific mechanisms of action and resistance pathways.
• Drug resistance, driven by genetic mutations in transporters and enzymes, complicates treatment efficacy for both AAT and HAT.

Purpose of the Study:

• To review the mechanisms of resistance to various trypanocidal drugs used in treating African trypanosomiasis.
• To highlight the genetic basis of drug resistance in Trypanosoma parasites.
• To inform the development of novel therapeutic strategies against resistant trypanosome strains.

Main Methods:

• Literature review of existing studies on trypanocidal drug mechanisms and resistance.
• Analysis of genetic mutations and alterations in transport proteins associated with drug resistance.
• Comparison of resistance profiles across different trypanocidal agents and Trypanosoma species.

Main Results:

• Suramin resistance linked to altered transport proteins; melarsoprol resistance to P2 transporter mutations.
• Eflornithine resistance associated with TbAAT6 gene mutations; nifurtimox resistance with nitroreductase gene copy loss.
• Fexinidazole resistance involves trypanosome bacterial nitroreductases; AAT drug resistance linked to mitochondrial membrane potential and transporters.

Conclusions:

• Drug resistance in African trypanosomiasis is multifaceted, involving diverse genetic and molecular mechanisms.
• Combination therapies like nifurtimox-eflornithine are adopted for HAT due to monotherapy resistance and side effects.
• Further research is needed for novel therapies targeting drug resistance in AAT, mirroring progress in HAT drug development.