Ethnopharmacology and the practice phytotherapy

Phytotherapy also is a fast developing field of practice and research with a long tradition, but most commonly linked to the practice in Europe and some other regions. Ethnopharmacology, on the other hand has a much shorter history as a well-defined field of research. The term was first used in 1967 in the context of the search for psychoactive drugs and today thousands of articles cover the local and traditional uses, pharmacological activity/safety and composition of 'traditional' medicines. Researchers with diverse backgrounds including pharmaceutical scientists, pharmacologists, anthropologists, biologists, botanists, toxicologists, and practitioners/researchers of the diverse medical traditions are all involved in such research. Especially, in most of the so-called BRICS and MINT countries (Brazil, India, China, South Africa; México, Indonesia, Nigeria and Turkey), but also in many other emerging economies like Thailand and Malaysia ethnopharmacological research is flourishing [1]. Again a key focus is on improving therapeutic praxis and to develop a better evidence base.

In recent decades what initially sounded like a two very distinct fields of research and practice, has moved closer and closer together, most certainly also driven by the need of phytotherapy to find new ways to provide new integrative solutions to the health care needs of rapidly changing societies. Using two examples from our own research, I want to highlight current trends and research needs. In an increasingly interconnected world emerging themes have come into the center of scientific attention like for example value chains of medicinal plants. Research into these chains highlights problems like exploitation through middlemen, over-harvesting of wild medicinal plants, adulteration and contamination of products at different stages along the chain and a general lack of traceability through the different stages of production. Ethnopharmacology offers both a new framework for research and new strategies for resolving some of the key problems. There are benefits to farmers that belonged to an integrated chain and the resulting products were subject to a higher standard of processing and storage. By using analytical methods, including HPTLC and ¹H-NMR, we were able to correlate some variations in product composition for selected producers and identify strengths and weaknesses of some types of value chains. Examples from our research include Rhodiola spp. [2], Hypericum perforatum L., Ginkgo biloba L. and Curcuma longa L.

A second main example explores Nigella sativa L. – black seeds, a spice and traditional herbal medicine used in various diseases including bronchial asthma. The seeds are of outstanding importance as a medicine in many Arabic countries and could be therapeutically beneficial in alleviating airway inflammation and the control of asthma symptoms, but the evidence remains scanty and is often based on poorly characterised preparations. Accordingly, well-designed large clinical studies using chemically well characterised black seed preparation are required. In a study we conducted during 2015, 80 patients were enrolled, with 40 patients each randomly assigned to treatment and placebo groups. After 4 weeks, 10 patients had withdrawn from each group. The black seed preparation showed a statistically significant improvement in the Asthma Control Test (mean = 21.1 (SD = 2.6) vs. mean = 19.6 (SD = 3.7), p = 0.044) and blood eosinophils (median = –0.050 (–0.155 – –0.001) vs. 0.015 (–0.060 – 0.087), p = 0.008). Black seed non-significantly elevated predicted 'Forced expiratory volume in 1 second'. Changes in INF-gamma, IL-10, and IL-12p70 were noteworthy between groups. Overall, black seeds appeared to improve asthma symptoms and some asthma-related biomarkers [3]. Future studies should follow patients for longer periods.

Both examples showcase the need for transdisciplinary approaches, call for closer collaboration between ethnopharmacology and phytotherapy and more specifically for conceptual and methodological strategies which help to develop integrative health care globally.

References:

[1] Heinrich M, Jaeger AK, eds. Ethnopharmacology. Chichester: Wiley; 2015

[2] Booker A et al. Phytomedicine 2016; 23: 754 – 762

[3] Koshak A et al. Phytother Res 2017; 31: 403 – 409