Ethnopharmacological in vitro studies on Austria's folk medicine--an unexplored lore in vitro anti-inflammatory activities of 71 Austrian traditional herbal drugs.

ETHNOPHARMACOLOGICAL RELEVANCE: In Austria, like in most Western countries, knowledge about traditional medicinal plants is becoming scarce. Searching the literature concerning Austria's ethnomedicine reveals its scant scientific exploration. Aiming to substantiate the potential of medicinal plants traditionally used in Austria, 63 plant species or genera with claimed anti-inflammatory properties listed in the VOLKSMED database were assessed for their in vitro anti-inflammatory activity. MATERIAL AND METHODS: 71 herbal drugs from 63 plant species or genera were extracted using solvents of varying polarities and subsequently depleted from the bulk constituents, chlorophylls and tannins to avoid possible interferences with the assays. The obtained 257 extracts were assessed for their in vitro anti-inflammatory activity. The expression of the inflammatory mediators E-selectin and interleukin-8 (IL-8), induced by the inflammatory stimuli tumor necrosis factor alpha (TNF-α) and the bacterial product lipopolysaccharide (LPS) was measured in endothelial cells. The potential of the extracts to activate the nuclear factors PPARα and PPARγ and to inhibit TNF-α-induced activation of the nuclear factor-kappa B (NF-κB) in HEK293 cells was determined by luciferase reporter gene assays. RESULTS: In total, extracts from 67 of the 71 assessed herbal drugs revealed anti-inflammatory activity in the applied in vitro test systems. Thereby, 30 could downregulate E-selectin or IL-8 gene expression, 28 were strong activators of PPARα or PPARγ (inducing activation of more than 2-fold at a concentration of 10µg/mL) and 21 evoked a strong inhibition of NF-κB (inhibition of more than 80% at 10µg/mL). CONCLUSION: Our research supports the efficacy of herbal drugs reported in Austrian folk medicine used for ailments associated with inflammatory processes. Hence, an ethnopharmacological screening approach is a useful tool for the discovery of new drug leads.

Identification of ostruthin from Peucedanum ostruthium rhizomes as an inhibitor of vascular smooth muscle cell proliferation.

Inhibition of vascular smooth muscle cell (VSMC) proliferation is of substantial interest in combating cardiovascular disease. A dichloromethane extract from the rhizomes of Peucedanum ostruthium, a traditionally used Austrian medicinal plant with anti-inflammatory properties, was examined for a putative antiproliferative activity in rat aortic VSMC. This extract inhibited serum (10%)-induced VSMC proliferation concentration dependently. Further identification and biological testing of its major constituents revealed that the coumarin ostruthin (7) is the major antiproliferative substance. In summary, a new bioactivity of P. ostruthium rhizomes is described, and 7 has been identified as the responsible compound.

Identification and quantification of coumarins in Peucedanum ostruthium (L.) Koch by HPLC-DAD and HPLC-DAD-MS.

The rhizomes of Peucedanum ostruthium (L.) Koch (masterwort) are traditionally used in the alpine region as ingredient of liqueurs and bitters, and as a herbal drug. A sensitive and specific high-performance liquid chromatography-diode-array detection-mass spectrometry (HPLC-DAD-MS) method has been developed for the simultaneous identification and quantification of its main coumarins, oxypeucedanin hydrate, oxypeucedanin, ostruthol, imperatorin, osthole, isoimperatorin, and ostruthin. Fast HPLC separation could be achieved on an Acclaim C18 column (150 mm × 2.1 mm i.d., 3 µm) using a mobile phase gradient of acetonitrile-water modified with 0.01% acetic acid. The quantification by HPLC-DAD was performed with imperatorin as external standard and validated to demonstrate selectivity, linearity, precision, and accuracy. The content of the main coumarins was quantitated in various batches of commercial and field-collected rhizomes of Peucedanum ostruthium, as well as in beverages prepared thereof.