Spirostanol Sapogenins and Saponins from Convallaria majalis L. Structural Characterization by 2D NMR, Theoretical GIAO DFT Calculations and Molecular Modeling.

Two new spirostanol sapogenins (5ß-spirost-25(27)-en-1ß,2ß,3ß,5ß-tetrol 3 and its 25,27-dihydro derivative, (25S)-spirostan-1ß,2ß,3ß,5ß-tetrol 4) and four new saponins were isolated from the roots and rhizomes of Convallaria majalis L. together with known sapogenins (isolated from Liliaceae): 5ß-spirost-25(27)-en-1ß,3ß-diol 1, (25S)-spirostan-1ß,3ß-diol 2, 5ß-spirost-25(27)-en-1ß,3ß,4ß,5ß-tetrol 5, (25S)-spirostan-1ß,3ß,4ß,5ß-tetrol 6, 5ß-spirost-25(27)-en-1ß,2ß,3ß,4ß,5ß-pentol 7 and (25S)-spirostan-1ß,2ß,3ß,4ß,5ß-pentol 8. New steroidal saponins were found to be pentahydroxy 5-O-glycosides; 5ß-spirost-25(27)-en-1ß,2ß,3ß,4ß,5ß-pentol 5-O-ß-galactopyranoside 9, 5ß-spirost-25(27)-en-1ß,2ß,3ß,4ß,5ß-pentol 5-O-ß-arabinonoside 11, 5ß-(25S)-spirostan-1ß,2ß,3ß,4ß,5ß-pentol 5-O-galactoside 10 and 5ß-(25S)-spirostan-1ß,2ß,3ß,4ß,5ß-pentol 5-O-arabinoside 12 were isolated for the first time. The structures of those compounds were determined by NMR spectroscopy, including 2D COSY, HMBC, HSQC, NOESY, ROESY experiments, theoretical calculations of shielding constants by GIAO DFT, and mass spectrometry (FAB/LSI HR MS). An attempt was made to test biological activity, particularly as potential chemotherapeutic agents, using in silico methods. A set of 12 compounds was docked to the PDB structures of HER2 receptor and tubulin. The results indicated that diols have a higher affinity to the analyzed targets than tetrols and pentols. Two compounds (25S)-spirosten-1ß,3ß-diol 1 and 5ß-spirost-25(27)-en-1ß,2ß,3ß,4ß,5ß-pentol 5-O-galactoside 9 were selected for further evaluation of biological activity.

Influence of Echinacea purpurea intake during pregnancy on fetal growth and tissue angiogenic activity.

The process of angiogenesis and control of blood vessels sprouting are fundamental to human health, as they play key roles in many physiological and pathological conditions. Intake of different pharmaceuticals with antiangiogenic activity by pregnant women may lead to severe developmental disturbances as it was described in case of thalidomide. It may also cause immunomodulatory effects as it was shown for antibiotics, theobromine, caffeic acid or catechins on the pregnant mice model. At present, Echinacea purpurea-based phytoceuticals are among the most popular herbals in the marketplace. Many compounds of Echinacea extracts (polysaccharides, alkamides, polyphenols, glycoproteins) exert immunomodulatory, anti-oxidative and anti-inflammatory activity. Echinacea is one of the most powerful and effective remedies against many kinds of bacterial and viral infections. In previous studies we shown significant inhibitory effect of the Echinacea purpurea based remedy on tumour angiogenic activity using cutaneous angiogenesis test, and an inhibitory effect on L-1 sarcoma growth was observed . The aim of the present study was to establish whether pharmaceuticals containing alcoholic extracts of Echinacea purpurea given to pregnant mice influence angiogenic activity and tissue VEGF and bFGF production of their fetuses. We showed that angiogenic activity of tissue homogenates was increased in Esberitox group and diminished in case of Immunal forte as compared to standard diet group. In case of Echinapur group we did not find significant differences in angiogenic activity. VEGF and bFGF concentration were lower in all groups compared to the control. In the case of Echinapur and Esberitox number of fetuses in one litter were slightly lower as compared to control group, but the difference is on the border of statistical significance. In conclusion, there is some possibility that pharmaceuticals containing Echinacea purpurea might influence fetal development in human also, because they may interfere with embrional angiogenesis , and should not be recommended for pregnant women.

Anti-angiogenic activity of convallamaroside, the steroidal saponin isolated from the rhizomes and roots of Convallaria majalis L.

Angiogenesis plays a pivotal role in tumor growth and represents a key target for chemopreventive intervention. Despite the large number of existing angiogenesis inhibitors, there is still a great demand for new anti-angiogenic compounds. The objective of this study is to investigate the effect of administration of convallamaroside, a steroidal saponin isolated from the lily of the valley (Convallaria majalis L.) to mice on tumor angiogenesis reaction induced by tumor cells. Angiogenic activity was evaluated by mice intradermal test. Convallamaroside showed a significant inhibitory effect on the number of new vessels induced in mice by human kidney tumor cells (p < 0.001). Similarly, administration of convallamaroside to mice decreased the number of new vessels induced by sarcoma mice cells (p < 0.001).

Suppression of angiogenic activity of sera from diabetic patients with non-proliferative retinopathy by compounds of herbal origin and sulindac sulfone.

Angiogenesis, the process of new blood vessel formation, is the key event in the mechanism of several pathological processes including diabetic retinopathy. The physiological control of angiogenesis depends on the balance between stimulatory and inhibitory factors. Therefore, a number of anti-angiogenic approaches has been developed, many of them based on the inhibition of the functional activity of pro-angiogenic factors. The aim of the present study was to compare the anti-angiogenic effectiveness of sulindac sulfone and some herbal compounds in the serum-induced angiogenesis test performed in Balb/c mice. Pooled sera from 35 patients with diabetes type 2 and retinopathy were used as pro-angiogenic stimuli. The strongest inhibitory effect was observed for the sulindac sulfone and ursolic acid in the highest concentration of 200 micro g/ml, as well as for the low-dosage concomitant treatment with 2 micro g/ml of epigallocatechin gallate (EGCG, green tea flavanol), ursolic acid (plant-derived triterpenoid), sulindac sulfone and convalamaroside (steroidal saponin). Combination treatment was significantly more effective than monotherapy with medium (20 micro g/ml) or lowest doses of tested compounds. The present study is the first to demonstrate the potent anti-angiogenic effect of the combination therapy comprising of plant-derived extracts and sulindac sulfone, as tested in the in vivo angiogenesis experimental model with sera of non-proliferative diabetic retinopathy patients used as the pro-angiogenic stimuli. We think that it might be the first step toward application of some of these compounds, in the future, in preventive anti-angiogenic therapy of these patients, as well, as in the treatment of later, proliferative stage of this disease.