Planta Medica, Table of Contents Planta Med 1996; 62(2): 106-110DOI: 10.1055/s-2006-957828 Papers © Georg Thieme Verlag Stuttgart · New York The Effect of Purified Extract of Fagopyrum esculentum (Buckwheat) on Protein Kinases Involved in Signal Transduction Pathways D. Samel1 , A. Donnella-Deana2 , P. de Witte1 1Laboratorium voor Farmaceutische Biologie en Fytofarmacologie, Faculteit Farmaceutische Wetenschappen, K. U. Leuven, B-3000 Leuven, Belgium 2Dipartimento di Chimica Biologica and Centre per lo Studio della Fisiologia Mitochondriale del CNR, Università di Padova, 1-35,100 Padova, Italy Recommend Article Abstract PDF Download Buy Article Abstract The effect of a purified extract of the flowering herb of Fagopyrum esculentum (buckwheat) on various protein kinases involved in signal transduction was examined. We observed that buckwheat contains red fluorescent compounds having photosensitizing properties. Spectrophotometric analysis of the extract has indicated structural similarity to hypericin. Dose- and light-dependent inhibition of various protein kinases was observed. The purified buckwheat extract strongly inhibited two receptor-associated protein tyrosine kinases (ECF-R and Ins-R) and a Ser/Thr kinase (PK-C) at an ng/ml concentration range. Selectivity was exhibited as a decreased sensitivity to cytosolic PTKs and protein kinase CK-2. The protein kinases are important components of the signal transduction pathway. Aberration of signal transduction is a hallmark of several proliferative diseases. Our results indicate that photosensitizing compounds in buckwheat are potential antiproliferative agents. Key words Fagopyrum esculentum - Polygonaceae - fagopyrin - protein kinase - inhibition PDF (448 kb)
