Saponin hemolysis

Seeman, P., Cheng, D., and lies, G. (1973). Structure of membrane holes in osmotic and saponin hemolysis. ]. Cell Biol. 56, 519-527. 

Assa, Y., Shany, S., Gestetner, B., Tencer, Y., Birk, Y., and Bondi, A. (1973) Interaction of alfalfa saponins with components of the erythrocyte membrane in hemolysis. Biochim. Biophys. Acta 307, 83-91. 

Seeman, P. (1967) Transient holes in the erythrocyte membrane during hypotonic hemolysis and stable holes in the membrane after lysis by saponin and lysoleci-thin. J. Cell Biol. 32, 55-70. 

Saponins consist of a terpenoid core (the aglycone), having oxygenated positions bound to sugar moieties (up to ten monosaccharidic units). In water they form colloidal solutions which foam on shaking and precipitate cholesterol. When saponins are near cell membranes, their interaction with cholesterol may create pore-like structures that eventually cause the membrane to burst. Hemolysis is an example of this phenomenon (i.e. the distraction of erythocyte membranes, but not hemoglobin). Occasionally, they cause hypersecretion, which could explain their expectorant activities and also their toxicity to fish. 

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. 

Saponins have been considered toxic for different organisms. Meyer et ah (1990) found toxicity to brine shrimp. Woldemichael and Wink (2001) found monodesmoside saponins hemolytically active. The hemolysis may be produced by the interaction of the saponins with membranes, producing pores that lead to rupture of the (Seeman et ah, 1973). Kuljanabhagavad et ah (2008) described mainly saponins with an aldehyde group as cytotoxic in HeLa (cervix adenocarcinoma) cell line. 

A good deal of work on the ability of saponins to produce hemolysis of blood in vitro has been reported since more than 30 years and it is therefore appropriate to summarize here current data. As well known, cytotoxic, antifungal and hemolytic effects correlate with each other and are due to the glycoside membranotropic action. When the saponins are in the proximity of cell membranes, their interaction with cholesterol may create pore-like structures visible in the electron microscope leading eventually to the bursting of the membrane and releasing of hemoglobin in the medium. 

B All saponins of the drug samples 1-4. show white hemolysis zones on a red-brown background with the blood reagent. 

Detection of saponins white zones are formed against the reddish background of the plate. Hemolysis maybe immediate or may occur when the plate has been dried under slight wanning. 

Takechi, M., Shimada, S., and Tanaka, Y (1992) Time course and inhibition of saponin-induced hemolysis. P/anto Afec 58, 128-130. 

Zhang, J., Z. Meng, M. Zhang, et al. 1999. Effect of six steroidal saponins isolated from Anemarrhenae rhizoma on platelet aggregation and hemolysis in human blood. Clin. Chim. Acta 289(l-2) 79-88. 

Saponins - Saponins are glycosides that make suds when shaken in water. The name comes from the Latin word Sapo meaning soap. Saponins are used as expectorants, diuretics, hypotensives and hypocholesterolemics. Saponins from Aralia mandschurica, Echinopanax elatus, Eleutherococcus spp., and Panax spp. have stimulating effects. Saponins cause hemolysis after intravenous introduction. Because of this, they are only introduced orally. 

One characteristic of many (but not all) saponins is their capacity to rupture erythrocytes (red blood corpuscles). By measuring the change in absorbance of the supernatant of an erythrocyte suspension after hemolysis, the saponin content can be calculated. Various amounts of the saponin-containing product or extract are mixed with a suspension of washed erythrocytes in isotonic buffer at pH 7.4. After 24 h, the mixture is centrifuged and hemolysis is indicated by the presence of hemoglobin (red) in the supernatant. In the European Pharmacopoeia, the quantity in milliliters of ox blood (diluted 1 50) that is totally hydrolysed by 1 g of test substance is measured. As a standard, the saponin mixture from the roots of Gypsophila paniculata (Caryophyllaceae) has by definition an activity of 30 000 units. 

Because saponins are surface-active agents and act as detergents, they can inactivate a number of enzymes. Many saponins also cause disintegration of membranes and, in the case of erythrocytes, they cause hemolysis. This action is related to the presence of cholesterol, as addition of cholesterol counters some of the deleterious effects of saponins (Agarwal and Rastogi, 1974). Addition of cholesterol also causes precipitation of certain saponins from aqueous solutions (Bondi et al., 1973). 

Reim, V. and Rohn, S. 2014. Characterization of saponins in peas (Pisum sativum L.) by HPTLC coupled to mass spectrometry and a hemolysis assay, Food Res. Int., article in press, http //dx.doi.Org/10.1016/j.foodres.2014.06.043. 

Kensil et al. (1991) have isolated four saponins from Quillaja bark termed QS-7, QS-17 (1), QS-18 (2) and QS-21 (3) [13, 14]. They were found to be adjuvant-active, although differing in biological activities such as hemolysis and toxicity in mice. Interestingly, QS-7 and QS-21 (3) had lower toxicity than Quil A or QS-18 (2) as determinated by lethality studies in mice. 

Baumann E, Stoya G, Volkner A et al (2000) Hemolysis of human erythrocytes with saponin affects the membrane structure. Acta Histochem 102 21—35 Benchaar C, McAllister TA, Chouinard PY (2008) Digestion, ruminal fermentation, ciliate protozoal populations, and milk production from dairy cows fed cinnamaldehyde. Quebracho condensed tannin, or Yucca schidigera saponin extracts. J Dairy Sci 91 4765-4777. doi 10.3168/ jds.2008-1338... 

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