Saponins release

Saponins/released to the new and known triterp. saponins, responsible for the Aquatic Ranunculus fluitans... 

Saponins. Although the hypocholesterolemic activity of saponins has been known since the 1950s, thek low potency and difficult purification sparked Htde interest in natural saponins as hypolipidemic agents. Synthetic steroids (292, 293) that are structurally related to saponins have been shown to lower plasma cholesterol in a variety of different species (252). Steroid (292) is designated CP-88,818 [99759-19-0]. The hypocholesterolemic agent CP-148,623 [150332-35-7] (293) is not absorbed into the systemic ckculation and does not inhibit enzymes involved in cholesterol synthesis, release, or uptake. Rather, (293) specifically inhibits cholesterol absorption into the intestinal mucosa (253). As of late 1996, CP-148,623 is in clinical trials as an agent that lowers blood concentrations of cholesterol (254). 

Kimura, Y., Okuda, H., and Arichi, S. (1988). Effects of various ginseng saponins on 5-hydroxytryptamine release and aggregation in human platelets. /. Pharm. Pharmacol. 40, 838-843. 

Lee, T.-F., Shiao, Y.-J., Chen, C.-F., and Wang, L. C. H. (2001). Effect of ginseng saponins on P-amyloid-suppressed acetylcholine release from rat hippocampal slices. Planta Med. fPl, 634-637. 

Vascuiar and sexuai effects Ginseng saponin has demonstrated vasoactive effects. It activates the release of NO from bovine aortic endothelium, and from the endothelial cells and perivascular nerve of the rabbit corpus cavernosum (Kim HS et al. 1998 Ko et al. 1996 Choi and Seong 1995 Chen and Lee 1995). Nitric oxide synthesis is also observed in the endothelium of the lung, heart, and kidney (Gillis 1997). 

Ginseng s mechanism of vasorelaxation and nitric oxide release is probably by conversion of L-arginine to L-citrulline (Kim H et al. 1992). Ginseng saponin induces relaxation of the corpus cavernosum smooth muscle in a dose-dependent manner (Kim HJ et al. 1998). This effect is... 

In addition to fish oil, nutrigenomic studies have identified other possible modulators of TNF-a production and/or release in vitro. Kang et al. reported that soybean saponins suppressed the release of TNF-a by LPS-stimulated murine peritoneal macrophages.100 Horrigan et al. demonstrated that concentrations of caffeine that were relevant to human consumption consistently suppressed the production of TNF-a in human blood.101 Clearly, more studies that address the anti-inflammatory effects of food components in studies involving humans are warranted. 

Kang J-H, Sung M-K, Kawada T et al. Soybean saponins suppress the release of proin-flammatory mediators by LPS-stimulated peritoneal macrophages. Cancer Lett. 2005, 230 219-227. 

AIII (triterpene saponin) (Liliaceae) [rhizome] insulin release effect) (STZ-DB mouse) [gluco neogenesis, glycogenolysis]... 

Lipophilic compounds, such as the various terpenoids, tend to associate with other hydrophobic molecules in a cell these can be biomembranes or the hydrophobic core of many proteins and of the DNA double helix [10,18,24,25]. In proteins, such hydrophobic and van der Waals interactions can also lead to conformational changes, and thus protein inactivation. A major target for terpenoids, especially saponins, is the biomembrane. Saponins (and, among them, the steroid alkaloids) can change the fluidity of biomembranes, thus reducing their function as a permeation barrier. Saponins can even make cells leaky, and this immediately leads to cell death. This can easily be seen in erythrocytes when they are attacked by saponins these cells burst and release hemoglobin (hemolysis) [1,6,17]. Among alkaloids, steroidal alkaloids (from Solanaceae) and other terpenoids have these properties. 

As shown in "Figs. (34) and (35) ", among the six saponins tested, only ginsenoside Rgi "Fig. (36)" inhibited adrenaline- and thrombin-induced platelet aggregation and 5-HT release dose-dependently. 

El Izzi A, Benie T, Thieulant M-L, Le Men-Olivier L, Duval J (1992) Stimulation of LH Release from Cultured Pituitary Cells by Saponins of Petersianthus macrocarpus A Permeabilising Effect. Planta Med 58 229... 

Except for one study (Haeusler et ah, 1981), no response to agonists was observed after saponin per-meabilization. Haeusler modified the saponin per-meabilization using high concentrations of saponin (500 xg/ml) for a very brief period (5-6 min). Mesenteric arteries skinned in this way responded to noradrenaline with a contraction that was attributed to release of Ca2+ from internal stores. Saponin-treated smooth muscle, however, responds to GTP7S, a poorly hydrolyzable GTP analog, which permanently activates G proteins (Fujiwara et ah, 1989 Hirata et ah,... 

The permeabilization protocol with (3-escin is similar to that applied for saponin skinning (Kobayashi et ah, 1989). The pores are quite large, allowing even antibodies to permeate (lizuka et ah, 1994). In these preparations, the pharmacomechanical coupling is functionally intact as judged from the agonist-induced release of Ca + from intracellular stores and increase in Ca + sensitivity of the myofilaments (Kobayashi et ah, 1989). One criterion for complete permeabilization again is the amplitude of maximal Ca +-activated... 

Smooth muscle preparations permeabilized with saponin, p-escin, or a-toxin have significantly contributed to the understanding of Ca2+ release from intra-... 

In general, the stores are loaded with Ca + buffered with millimolar concentrations of EGTA (Endo et al., 1977 Saida and Nonomura, 1978 Itoh et al., 1982a,b Saida, 1982). The stores are fully loaded within 3 to 5 min at 1 (jlM Ca2+ (Saida, 1982), whereby the Ca2+ uptake depends on the Ca + concentration (Saida, 1982 Yamamoto and van Breemen, 1986). At Ca + concentrations greater than 1 jlM, a Ca +-induced Ca release was observed (Itoh et al., 1981 Saida, 1982). The deposition of Ca2+ in the SR of saponin-permeabilized smooth muscle was demonstrated by electron probe X-ray microanalysis (Kowasaki et al.,... 

The chemistry of echinoderms, particularly the Holothuroidea (sea cucumbers) is characterized by the presence of saponins (triterpene glycosides) and sterol sulfates. Saponins are released by the sea cucumber s Cuvier gland when the organism is threatened. A number of biosynthetic investigations have addressed the origins of saponins and have yielded conflicting results. 

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