Brain, joint, gut: Inflammation as link between depression, rheumatism and irritable bowel syndrome
Introduction: For a large number of diseases, inflammation has been shown to be a key factor. This includes also diseases far beyond those classically known, as e.g. functional gastrointestinal diseases and psychic depression. Herbal medicines are an important treatment option in this field.
Aim: Over the last years, modern in vitro methods have helped to uncover many mechanisms of action of herbal medicines. This is exemplified by studies with willow bark extract and fixed combination products.
Method: Suitable examples were selected which are useful for showing these mechanisms.
Results: Willow bark extract has recently been shown to have, beside its anti-rheumatic effects, also anti-depressant properties, and has been studied using the AAPH and XOD reactions. For the extract STW 33-I it could thereby be uncovered that it is more than salicin, as the polyphenols play a leading role in its anti-inflammatory action . For a combination product used in the same indication (STW 1) the additive action of its components in the AAPH reaction and the supraadditive action in a more complex ex vivo model  was shown. Also for STW 5, used in functional gastrointestinal diseases, an anti-inflammatory action was shown in specific, newly developed in vitro models . These data are in accordance with in vivo studies on these herbal medicines .
Conclusion: The multiple components of herbal medicines have multiple targets, involved in their anti-inflammatory action, and are a base of synergisms which are crucial for their success in therapy.
Dedication: This contribution is dedicated to Prof. Dr. H. Heinle, Institute for Physiology, University of Tübingen, on the occasion of his retirement.
Keywords: Inflammation, willow bark, Phytodolor, Proaktiv, Iberogast, functional dyspepsia, in vitro, pharmacology
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