Quality Assessment of Medicinal Product and Dietary Supplements Containing Vitex agnus-castus by HPLC Fingerprint and Quantitative Analyses.

In this study, we aimed to evaluate the quality of 11 products sold in Japan (one medicinal product and 10 dietary supplements) containing/claiming to contain chasteberry extract (fruit of Vitex agnus-castus L.) using HPLC fingerprint (15 characteristic peaks), quantitative determination of chemical marker compounds, and a disintegration test. The HPLC profile of the medicinal product was similar to that of the reference standard of V. agnus-castus fruit dry extract obtained from European Directive for the Quality of Medicines (EDQM), whereas the profiles of some dietary supplements showed great variability, such as different proportions of peaks or lack of peaks. Results of the principal component analysis of the fingerprint data were consistent with those of the HPLC profile analysis. The contents of two markers, agnuside and casticin, in dietary supplements showed wide variability; this result was similar to that achieved with the HPLC fingerprint. In particular, agnuside and/or casticin was not detected in two dietary supplements. Furthermore, one dietary supplement was suspected to be contaminated with V. negundo, as evidenced from the results of agnuside to casticin ratio and assay of negundoside, a characteristic marker of V. negundo. Results of the disintegration test showed poor formulation quality of two dietary supplements. These results call attention to the quality problems of many dietary supplements, such as incorrect or poor-quality origin, different contents of the active ingredient, and/or unauthorized manufacturing procedures.

Quality evaluation of medicinal products and health foods containing chaste berry (Vitex agnus-castus) in Japanese, European and American markets.

The aim of present study was to evaluate the qualities of chaste berry (fruit of Vitex agnus-castus L.) preparations using HPLC fingerprint analysis. Seven medicinal products 1 from Japan and 6 from Europe, and 17 health foods, 6 from Japan and 11 from the United States were analyzed. HPLC profile and 26 authentic peaks were compared medicinal products and health foods. Whereas medicinal products had similar HPLC profiles, health foods had various profiles and each peak was also greatly different. The measured amounts of two markers in 5 traditional medicinal products, agnuside and casticin specified in the European Pharmacopoeia (EP), the U.S. Pharmacopoeia (USP) or the WHO monographs of chaste berry, were much lower than those in 2 medicinal products defined as "well-established use" by the European Medicines Agency. The amounts of two markers for 17 health foods differed in a great deal from 14-5054% and 3-1272%, respectively. Furthermore the amount ratios of two markers, agnuside/casticin, in about half of the health foods were remarkably larger than the standard crude drug and the ratios were closer to one of the related Chinese herbs, Vitex negundo L. It is concluded that a combination of HPLC fingerprints and the amount ratios of the marker compounds of chaste berry preparations serves as a useful tool to evaluate the qualities of these preparations.

Glycosaminoglycan and proteoglycan inhibit the depolymerization of beta2-microglobulin amyloid fibrils in vitro.

BACKGROUND: Although several kinds of evidence suggest that glycosaminoglycans (GAGs) and proteoglycans (PGs) may contribute to the development of beta2-microglobulin-related (Abeta2m) amyloidosis, the precise roles of these molecules for the development of Abeta2m amyloidosis are poorly understood. METHODS: We investigated the effects of GAGs and PGs on the depolymerization of Abeta2m amyloid fibrils at a neutral pH, as well as on the formation of the fibrils at an acidic pH in vitro, using fluorescence spectroscopy with thioflavin T and electron microscopy. RESULTS: Depolymerization of Abeta2m amyloid fibrils at pH 7.5 at 37 degrees C was inhibited dose-dependently by the presence of some GAGs (heparin, dermatan sulfate, or heparan sulfate) or PGs (biglycan, decorin, or keratan sulfate proteoglycan). Electron microscopy revealed that a significant amount of Abeta2m amyloid fibrils remained in the reaction mixture with some lateral aggregation. Second, when monomeric beta2m was incubated with aggrecan, biglycan, decorin, or heparin at pH 2.5 at 37 degrees C for up to 21 days, the thioflavin T fluorescence increased depending on dose and time. Electron microscopy revealed the formation of rigid and straight fibrils similar to Abeta2m amyloid fibrils in beta2m incubated with biglycan for 21 days. CONCLUSION: These results suggest that some GAGs and PGs could enhance the deposition of Abeta2m amyloid fibrils in vivo, possibly by binding directly to the surface of the fibrils and stabilizing the conformation of beta2m in the fibrils, as well as by acting as a scaffold for the polymerization of beta2m into the fibrils.