Natural Product-Based Drug Discovery Against Neglected Diseases with Special Reference to African Natural Resources

Chapter

Abstract

More than a billion people suffer from neglected tropical diseases (NTDs) which predominantly afflict people too poor to constitute a market attractive to private-sector research and development (R&D) investment. The discovery of antiparasitic new chemical entities (NCEs) based on ethnopharmacological approaches represents a major strategy for harnessing African biodiversity in the search for new drugs to combat NTDs as well as to address the ongoing emergence of resistance by causative protozoa. The ethnopharmacological use of medicinal plants for the treatment of parasitic diseases is well documented since ancient times, and the lessons learned from the application of such a strategy to the discovery of antiparasitic drugs are very well exemplified by the isolation of the first antimalarial drug quinine from Cinchona succirubra (Rubiaceae) and the currently widely prescribed antimalarial artemisinin from Artemisia annua. This chapter mainly highlights our experience in finding antiparasitic molecules with special bias towards the treatment of malaria, leishmania and trypanosomiasis. This chapter focuses on the disease burden of these neglected diseases, the challenges facing African scientists involved in this field of enquiry, and finishes up with some perspectives and conclusions. Due to the high number of natural products tested against the aforementioned protozoa in past years, the discussion is limited to some selected compounds from our own research. Research in our laboratory during the last 2 decades has mainly been directed towards the discovery of natural molecules active against NTDs. The compounds covered in this chapter highlight some selected examples of diverse secondary plant metabolites including sesquiterpenes, diterpenes, tripterpenes, tetranortriterpenes (limonoids) as well as acetogenins, flavonoids, lignans and alkaloids. This chapter also covers essential aspects related to the problems confronting African scientists who are currently engaged in this endeavour and suggests a strategy and mechanism streamlining drug discovery against NTDs.

Keywords

Human African Trypanosomiasis Antiplasmodial Activity Antiparasitic Activity Antiprotozoal Activity Antitrypanosomal Activity 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgement

The author would like to thank all previous and present collaborators for their inspiration over the last several years. In particular, I want to acknowledge the productive collaboration with Prof. Timothy Geary at Institute of Parasitology, McGill University, Canada; Prof. Thomas Schmidt at Institute of Pharmaceutical Biology and Phytochemistry, University of Münster, Germany; and Prof. Reto Brun and his group of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.

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Copyright information

© Springer Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.Faculty of PharmacyUniversity of Science & TechnologyKhartoumSudan

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