Both chemist and pharmacist, Professor Mehdi Beniddir explains to us how pharmacognosy enables the development of new medicines from substances produced by nature.
You received the bronze medal of the CNRS in 2022 for your research on pharmacognosy. Can you explain to us what that discipline consists of?
Mehdi Beniddir. It is a discipline that belongs to pharmaceutical sciences, and it is interested in natural substances and their pharmacological action. Etymologically, “pharmacognosy” means “knowledge of poisons or drugs.” My job, as a pharmacist and chemist, is to discover molecules, knowing that most of them are poisons, and make sure they become medicines. These molecules have different sources: plant, animal, fungal, fermentation and marine. Their therapeutic potential is therefore related to the function they perform in the natural environment, such as molecules used by plant and animal organisms to defend themselves.
What is the benefit of these molecules for humans?
MB You should know that almost 50% of the therapeutic arsenal used in clinics today comes from nature. This arsenal includes antibacterial, antifungal, anticancer antibiotics and even major immunosuppressants. As for me, my goal is to discover new natural substances that will serve as a source of inspiration for designing the antibiotics of tomorrow. However, the vast majority of pharmaceutical industries, which once swore by only natural substances, have now given up on pharmacognosy research. This research effort has now been transferred to academic laboratories.
Preparation of anti-malarial herbal tea based on “Artemisia annua”, at Providence Farm in Banigbé, Benin (April 2019).
What is the specificity of your research methods?
MB I develop strategies for the early discovery of new molecules based on chemoinformatics, which combines chemistry and artificial intelligence.
Almost 50% of the therapeutic arsenal used in clinics today comes from nature.
Digitization in particular enables the preservation of the historical heritage of the laboratory by storing spectral data of natural substances in databases that are accessible to the entire scientific community. It also allows improving the process of discovering natural substances and avoiding the re-isolation of already described substances.
Combined with the development of new analysis instruments and the emergence of big data, pharmacognosy is experiencing a true technological revolution. In addition, spectral data play a crucial role today: they provide valuable databases for training algorithms. machine learning (machine learning) and improve the processes that predict the structures of molecules. As such, heritage and museum specimens represent a veritable treasure trove of data to be digitized and shared.
Cycle of pharmacognosy research.
How do pharmacognosy, traditional medicine and pharmaceutical research work together?
MB Pharmacognosy expands the knowledge that is fundamental to a better understanding of living things and how we can use them. Pharmacy essentially combines many disciplines. My research work makes it possible to describe new natural molecules that expand the chemical repertoire in which pharmacy will try to identify a future drug candidate.
Traditional medicine remains the main source of care for 80% of the world’s population according to data from the World Health Organization.
Furthermore, pharmacognosy is closely related to traditional medicine because it draws its knowledge from ancestral knowledge. To this day, traditional medicine remains the main source of care for 80% of the world’s population according to the World Health Organization. Modern science has tried to rationalize these traditional preparations, which often consist of mixtures of plants and animals.
Artemisinin is an excellent example of an active ingredient discovered in traditional medicine: writings dating back to 168 BC. Kr. describe the use of annual wormwood tea to treat fever. The extraction of artemisinin from wormwood to treat malaria earned Chinese researcher Tu Youyou the 2015 Nobel Prize in Physiology or Medicine.
Pharmacologist Tu Youyou (right), here with her professor Lou Zhicen at the Chinese Academy of Medical Sciences in the 1950s, won the 2015 Nobel Prize in Physiology or Medicine for her research on artemisinin.
Explore biodiversity hotspots (hotspot) such as primary forests, associated with an ethnopharmacological screen also allow confirmation of traditional empirical observations. Indeed, when a traditional practitioner (traditional doctor) draws our attention to the use of a plant, we are particularly interested in it in order to isolate the active substance(s) and discover the benefits. Finally, cross-referencing historical data on the use of certain drugs or arrow poisons, chemistry, and modern computer tools makes it possible to trace the origins of plants and animals that existed in a different time and place.
How do you ensure that your research does not harm the protection of biological diversity?
MB Biodiversity conservation is at the center of my research work. This work falls within the strict framework of access to genetic resources and benefit-sharing arising from their use (APA), regulated by the Nagoya Protocol of 2010. By collecting prior consent for access to these resources, APA contributes to the promotion of conditions of access and use respecting the biological diversity that contains invaluable chemical wealth. The APA system also enables the improvement of legal security between suppliers and users, strengthening the traceability of resources and the transparency of use. In addition, we refer to the International Union for Conservation of Nature (IUCN) inventory to assess the status of the species we study.
An artemisinin factory in Rong’an County, South China, 2015.
In the context of distrust towards “big pharma”, can remembering that medicines come from nature be reassuring?
MB It’s an argument that makes sense, but it’s abused by marketing that only uses it to sell. Under the pretense that products are natural or of natural origin, people may mistakenly think that they are devoid of any toxicity. Do not forget that herbal medicines can lead, in combination with “conventional” medicines, to drug interactions with serious consequences. Let’s not forget that the greatest poisons in history are natural. Many believe that the use of herbs in the form of herbal tea or capsules is necessarily beneficial. This is indeed possible, but to be sure, a rigorous analysis of the benefits of the plants in question and a critical assessment of the benefit-risk ratio must first be carried out. This is partly what pharmacognosy does. ♦
Furthermore
Mehdi A. Beniddir and Erwan Poupon, “Chemistry of natural substances and pharmacy: at the crossroads”, Reports (Academy of Sciences), Chemistry, Online first (2023), pp. 1-15 (view, professional). doi: 10.5802/crchim.275.