Von der Ethnopharmakologie zur rationalen Phytotherapie: Phytochemische Charakterisierung und präklinische Untersuchungen zur potenziellen Wundheilungsaktivität von Extrakten aus Combretum mucronatum Schum& Thonn.

Kisseih E., Agyare C., Lechtenberg M., Petereit F., Sendker J., Brandt S., Hensel A.

Forschungsartikel (Zeitschrift)

Zusammenfassung

Summary Ethnopharmacology as a basis of scientific phytotherapy: Phytochemical characterization and pre-clinical studies of the potential of wound healing activity of leaf extracts from Combretum mucronatum Schum. & Thonn. Leaves from Combretum mucronatum Schum. & Thonn. are traditionally used for wound healing in Western Africa. Aqueous and hydroalcoholic extracts of the dried leaves have recently been shown to stimulate viability of human keratinocytes and dermal fibroblasts. The present study aimed to characterize the herbal material phytochemically, to develop a validated HPLC method for quality control of the herbal material, and to investigate the underlying pharmacological mechanism under in vitro conditions to understand the impact of C. mucronatum extracts on human skin cells. Materials and methods: Extracts obtained from the leaves of C. mucronatum by using solvents with different polarity (petroleum benzine, dichloromethane, ethanol-water 50 %, water) were investigated concerning phytochemical composition by GC-MS, LC-MS and in part after fractionation and isolation of purified compounds. For quality control of the herbal material an ICH-2 validated UHPLC method was developed for quantification of the lead compounds epicatechin, procyanidin B2, vitexin and isovitexin. In vitro studies were performed using HaCaT keratinocyte cell line, primary keratinocytes and primary skin fibroblasts with determination of viability (MTT assay), cell proliferation (BrdU incorporation ELISA), cell toxicity (LDH release) and keratinocyte differentiation, using involucrin and keratin K10 as differentiation marker (confocal laser scanning microscopy, Western blot). Results: A detailed phytochemical composition analysis of aqueous, hydroalcoholic, CH2Cl2 and petroleum benzine extracts from the leaves of C. mucronatum was performed and epicatechin, procyanidin B2, vitexin and isovitexin are assessed to be the lead compounds of the polar extract. Quantitative UHPLC investigations indicated mature leaves to have higher polyphenol content in comparison to young leaves. The drying process of the plant material was shown to have great influence on the content of the lead compounds. The aqueous extract (0.1 to 100 μg / mL) did not change cell viability of dermal fibroblasts and keratinocytes but inhibited cellular proliferation rates significantly at 100 μg / mL. The extract stimulated cellular differentiation of primary keratinocytes significantly at 1 and 10 μg / mL. Procyanidin B2 at 1 and 10 μM was shown to be responsible for the induction of this cellular differentiation, while epicatechin, and procyanidins B5, C1 and D1 were inactive. Conclusion: The in vitro effects of the aqueous extract on the skin cells rationalized the remedial effect in wound healing and possibly accounts for the reason why this plant may be widely used for this purpose. On the basis of this study extracts from the leaves of C. mucronatum therefore have potential for the use in wound healing.

Details zur Publikation

Herausgeber*innen:
Seiten: 7
Veröffentlichungsjahr: 2016
Verlag: Hippokrates Verlag GmbH
Sprache, in der die Publikation verfasst ist: Deutsch
Link zum Volltext: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84975464649&origin=inward