In order to evaluate sustainable sources of high-quality pharmaceutical starting material, a comparative study of 135 samples of red vine leaves of different origin was conducted to determine flavonol, anthocyanin and polyphenol contents. Total flavonol content was found to be between 0.6 % and 3.5 %, anthocyanin content between 0.2 % and 1.45 % and polyphenol content between 4.6 % and 18.9 %. The results are discussed in view of published data on red vine leaf components. In order to define the optimum timeframe for collecting leaves without damaging their grape-bearing vines the ontogenetic development of red vine leaves constituents was studied. High-performance liquid chromatography (HPLC) methods used for determining anthocyanins and flavonols in red vine leaves were validated and findings were compared to results produced by assays described in the French Pharmacopoeia. Whereas the correlation between conventional photometric and HPLC methods was satisfactory for anthocyanins, the correlation between the pharmacopoeia assay for total polyphenols and the HPLC analysis for flavonols was poor. As flavonol compounds are considered relevant for the vasoprotective effect of red vine leaves, their content in starting material used in the production of herbal medicines needs to be quantified.
The objective of these investigations was to further elucidate the immunopharmacological profile of fluid extracts of Eleutherococcus senticosus and to identify the specific role of its characteristic eleutherosides B and E. An ethanolic dry extract of Eleutherococcus senticosus was used as starting material for the isolation of the eleutherosides B and E. Immunopharmacological studies included expression of major histocompatibility complex class I and II molecules by rat bone marrow-derived mononuclear phagocytes, human lymphocyte marker flow cytometry, and in vitro testing of human lymphocyte functions. In contrast to the isolated eleutherosides B and eleutherosides E and the re-mixed eleutherosides B and E, the whole ethanolic fluid extract of Eleutherococcus senticosus was able to induce and enhance interleukin-1 and interleukin-6 but not interleukin-2 production in vitro. The effective concentration of the whole ethanolic extract ranged from 1.0-0.1 mg/ml for the enhancement of interleuking-1 alpha production and 1.0-0.03 mg/ml for the enhancement of interleukin-6 production. It is concluded that the observed enhancing immunopharmacological activities on acute phase response mediators are best exhibited by the induction with whole ethanolic extracts whereas the species-specific and characteristic eleutherosides B and E are not associated with these activities.
New methods are described that allow the selective isolation of venular endothelial cells and their cultivation on porous filters to confluent monolayers. These filters with the attached endothelial cell layer can be mounted in a specially adapted apparatus allowing not only blood filtration studies, but now also the continuous registration of hydraulic conductivity (Lp) of tissue layers. This preparation responds dramatically to certain release products from simultaneously activated blood platelets and polymorphonuclear granulocytes (PMN) with a rise in Lp that, in situ, would lead rapidly to local oedema, arteriolar constriction and venular thrombosis. Selectively activated PMN alone induced only a modest increase in endothelial Lp that could be prevented by uric acid, an antioxidant. ASA prevented the activation of the blood cells, but not the effect of the release products per se, implying that the release products are probably eicosanoids. A standardized extract from red vine leaves (AS 195, active ingredient of Antistax Venenkapseln), containing in particular the flavonoids quercetin-3-O-beta-D-glucuronide and isoquercitrin (quercetin-3-O-beta-D-glucoside), not only prevented the deleterious effect of the release products on the venular endothelial monolayers but, applied promptly to an endothelium damaged by prior exposure to these release products, resulted in the repair of the endothelium. These findings identify for the first time the venular endothelium as a possible important therapeutic target in certain vascular diseases, chronic venous insufficiency being perhaps the most prominent example.
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