Plants: between tradition and science

Humans have always been interested in plants, which have been for them a source of food (edible plants) but also a means of curing diseases (medicinal plants). Phytotherapy (or medicine using plants) is therefore as old as the hills. The history of phytotherapy can be divided into three main stages, each with a different level of use of the medicinal plant.

Up to the 18th century, use of the medicinal plant at a traditional level

Plants were the first and most important therapeutic tool available to humans, and this was the case for many centuries. From time immemorial, our distant ancestors have looked to plants for the remedy for their suffering. In many civilizations and on all continents, plant pharmacopeias were developed and were enriched through empiricism (knowledge derived from experience). With an unequalled gift for observation, our ancestors were able to demonstrate properties of medicinal plants that have never been contradicted through usage. The works of Dioscorides and Hildegarde von Bingen in particular, are famous for establishing these traditional remedies that were to be passed on through the centuries.

But this level of traditional approach had limits, which were those of scientific knowledge, both medical and pharmacological.

During the 19th century, use of the medicinal plant at a pharmacological level

Over the centuries, advances in scientific and medical knowledge along with technological developments gradually led to a path far removed from these “traditional remedies,” and instead to the use of the medicinal plant in a strictly pharmacological context.

Experimental demonstrations enabled the activity of certain constituents of plants (the active ingredients) to be shown, and different formulations (forms of administration) best adapted for better efficacy were studied. The advantage of this approach is that it allows the use of the medicinal plant according to precise pharmacological criteria, making it possible to move away from empiricism and the inaccuracies of the traditional approach.

However, this strictly pharmacological framework for the use of the medicinal plant also has its limits, which are those associated with the specificity of the plant itself: problems linked to the sheer number and complexity of the plant constituents, the difficulty of standardizing a plant-based product (variable quantity of plant constituents depending on the harvest period, geographical origin, and so on), making its pharmacological study difficult and possibly leading to paradoxical experiment results.

These difficulties, along with the quest for a more powerful and/or more easily reproducible action, gradually led to the abandonment of the medicinal plant in favor of the isolated active ingredient.

As a result, during the 19th century a whole series of active ingredients were isolated, leading to new medicines which undoubtedly contributed to improving expectation and quality of life: morphine was isolated from the poppy in 1817, codeine in 1832, quinine (anti-malarial) from cinchona in 1820, salicylic acid from willow bark in 1838 and digitalis (cardiotonic) from the foxglove in 1869... With the desire to develop medication that was more and more effective, the use of the medicinal plant in its entirety gradually became obsolete.

From the 20th century, use of the medicinal plant at a clinical level

The third level of study and use of the medicinal plant uses all the data resulting from stringent pharmacological analysis but reintegrates it into a living physiology with its fundamental concepts of dynamics, interactions and globality. As a result, the clinical approach can confirm certain properties that stem from tradition but are not found by strict pharmacological study.

This approach, which integrates study of the medicinal plant into a living physiology, brings us back, beyond the single active ingredient, to the value of using the plant totum, to the ideas of synergy and potentiation of the various constituents of the plant and in contrast suggests use of the medicinal plant in its entirety.

Current scientific knowledge and the recent introduction of “omics” technologies that allow the generation of massive amounts of data at multiple biological levels, and thus represent a powerful tool enabling us to understand how the plant functions as a whole, demonstrate the unparalleled richness of the plant totum and the relevance of its use.

Using the plant totum, with the concepts of synergy and potentiation, enables the use of lower doses compared to its isolated active ingredient for the same level of activity, thus avoiding the side effects specific to high doses (concepts of synergy of action and bioavailability).

Under these conditions, the plant totum is a valuable tool for providing the body with a chosen response so it can correct its dysfunctions, maintain its equilibrium and remain healthy.

Dr. Karine Ancolio Morcq

Source:

Carillon A. Place de la phytothérapie dans les systèmes de santé au XXI° s. – Conférence SIPAM –Djerba Mars 2009.