[Effect of ginsenoside Rh2 on the development of transferred tumors and chemotherapy efficiency].

Experiments on C57B1/6 mice showed that ginsenoside Rh2 inhibited the growth and metastasis process of Lewis lung tumor and increased the antitumor and antimetastatic effects of cyclophosphamide. On the model of transferred melanoma B-16, ginsenoside Rh2 showed a tendency to increase the antiblastome effect of the cytostatic drug.

Estrogenic activity of triterpene glycosides in yeast two-hybrid assay.

Estrogenic potency of six triterpene glycosides, Holothurin A, Holotoxin A1, Frondoside A, Cucumarioside A2-2 and Cauloside C, that are natural products and semi-synthesized Ginsenoside-Rh2, were examined with yeast two-hybrid system, including expressed genes of human estrogen receptor, hERalpha, the co-activator TIF2 and lacZ as a reporter gene. Only Ginsenoside-Rh2 exhibited significant moderate estrogenic activity in the concentration range of 10(-7) to 10(-6)M. Its effect was approximately 30% of the activity of 17beta-estradiol applied at half-effective concentration. This indicates Ginsenosides-Rh2 is a weak phytoestrogen. The sea cucumber triterpene glycosides, Holothurin A, Holotoxin A1, Cucumarioside A2-2 and Frondoside A, and plant glycoside Cauloside C had no appreciable estrogenic activity. Data obtained by yeast two-hybrid assay reflect structure-activity relationship between tested compounds and 17beta-estradiol. Only Ginsenoside-Rh2 has some similarity in chemical structure with 17beta-estradiol that might explain affinity of this glycoside to the hERalpha receptor.

Cytotoxicity of natural ginseng glycosides and semisynthetic analogues.

The cytotoxicity of natural glycosides from Ginseng, semisynthetic analogues and related triterpenes of the dammarane series, isolated from the leaves of the Far-East species of the genus Betula was studied in order to elucidate structure-activity relationships. Some of the compounds studied were active against the human lung carcinoma GLC4 and adenocarcinoma COLO 320 cell lines. The natural glycosides displayed the lowest cytotoxicity. The triterpenes of the dammarane series used as starting aglycones for semisynthetic derivatives were moderately cytotoxic. The dammarane triterpenes possessing keto groups and their semisynthetic glucosides were the most active compounds tested. Cytotoxic effects of the dammarane glucosides were inversely proportional both to the number of sugars attached to the aglycones and to the number of hydroxy groups of the aglycones. The type of side chain and the configuration of the hydroxy group at C-3 in aglycones did not have a significant influence on the cytotoxicity.

[Immunomodulating activity of tetracyclic triterpene glycosides of the dammarane and holostane series]. / Izuchenie immunomoduliruiushchei aktivnosti tetratsiklicheskikh triterpenovykh glikozidov dammaranovogo i golostanovogo riada.

Immunomodulating activity of triterpene glycosides of the holostan series (holoturins A and B, holoturin A2 and holotoxin A1) and triterpene glycosides of the dammaran series (3-O-monoglycoside,12-O-monoglycoside and 20-O-monoglycoside of protopanaxadiol and 3-O-monoglycoside of betulafolientriol) was studied in vitro. In low concentrations the triterpene glycosides showed mitogenic activity and modulated the immune response. The similarity in the action of the glycosides was first of all observed with respect to the dose-dependent duality of their effects i.e. the diametrically opposite action of the high and low doses. The expression of the effects was likely determined by the chemical structure of the triterpene glycosides. Liberation of the soluble mediators served as a secondary signal to the clonal expansion and differentiation of the cells.

[Comparative study of anti-tumor activity of the monoglucosides protopanaxadiol and betulafolientriol]. / Sravnitel'noe izuchenie protivoopukholevoi aktivnosti monogliukozidov protopanaksadiola i betulafolientriola.

Antitumor and cytotoxic activity of monoglucosides such as 3-0-panaxadiol (1), 12-0-panaxadiol (2) and 20-0-panaxadiol (3) and 3-0-betulafolientriol (4), 12-0-betulafolientriol (5) and 20-0-betulafolientriol (6) was studied. It was found that in concentrations of 10 to 50 micrograms/ml the above monosides induced marked impairment of the selective permeability of the tumor cells and the inhibition of the labeled precursor inclusion into the macromolecule biosynthesis. Administration of the monosides in a single dose of 100 mg/kg 24 hours after the inoculation of the Ehrlich tumor cells resulted in prolongation of the mean life-span of the mice by 144 per cent (1), 153 per cent (2), 144 per cent (3), 125 per cent (4), 133 per cent (5) and 178 per cent (6). A significant reduction of the tumor mass was observed at the early stages of the tumor development and later the tumor progress intensively resumed. The tests for the effect of the monoside-activated macrophages on the growth of the tumor cells showed that production of the growth factors by the macrophages was stable and had a negative action on the efficacy of the chemotherapy with the monoglucosides.

[Effect of glycosides of betulafolientriol and its 3-epimer on the growth of tumor cells in vitro]. / Vliianie glikozidov betulafolientriolai ego 3-épimera na rost opukholevykh kletok in vitro.

The effect of triterpene glycosides synthesized on the basis of betulafolientriol, ginsenoside Rb1 from gingseng, betulafolientriol and its 3-epimer on the growth of the Ehrlich tumor cell cultures was studied. It was shown that, in relation to the quantitative composition and sites of carbohydrate residue linkage to aglycone as well as configuration of the alpha- or beta-hydroxyl group at C-3, the activity of the triterpenoids of the dammaranic series changed within wide ranges. 3- and 12-0-beta-D-glycosides of 3-epibetulafolientriol proved to be the most active.

[The effect of the distribution of polar groups in a steroid molecule on its inhibition of Na+,K+-ATPase]. / Vliianie raspredeleniia poliarnykh grupp v molekule steroida na ego ingibiruiushchee deistvie na Na+,K+-ATPazu.

Transformed steroids having oxidized side chains in the D ring site and varying by polarity of the substituent at the ring A C(3)-position--acetates, glucosides or with free hydroxyls--in the concentration range 1 X 10(-4) - 1 X 10(-7) M were found to inhibit Na+, K+-ATPase. The extent of inhibition decreases with the rise in the polarity of the A region of the steroid molecule. With the compound devoid of polar groups in the D region an increase in the inhibitory activity is observed on passing from 3-acetate to 3-glucoside. The data obtained confirm the relationship between the extent of Na+, K+-ATPase inhibition and biphilicity of the molecule.