Beta-Hederin

A systematic study on the influence of the main ingredients of an ivy leaves dry extract on the beta2-adrenergic responsiveness of human airway smooth muscle cells.[Pubmed:25234924]

Pulm Pharmacol Ther. 2015 Apr;31:92-8.

The bronchospasmolytic and secretolytic effects of ivy leaves dry extracts can be explained by an increased beta2-adrenergic responsiveness of the bronchi. Recently, it was shown that alpha-hederin inhibits the internalization of beta2-adrenergic receptors (ss2AR) under stimulating conditions. alpha-Hederin pretreated alveolar type II cells and human airway smooth muscle cells revealed an increased ss2AR binding and an elevated intracellular cAMP level, respectively. In order to identify whether additional compounds also mediate an increased beta2-adrenergic responsiveness, we examined the ingredients of an ivy leaves dry extract (EA 575) protocatechuic acid, neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, rutin, kaempferol-3-O-rutinoside, 3,4-, 3,5- and 4,5-dicaffeoylquinic acid, hederacoside B, and Beta-Hederin. Within all the tested substances, only Beta-Hederin inhibited the internalization of GFP-tagged ss2AR in stably transfected HEK293 cells. Using fluorescence correlation spectroscopy Beta-Hederin (1 muM, 24 h) pretreated HASM cells showed a statistically significant increase in the ss2AR binding from 33.0 +/- 8.9% to 44.1 +/- 11.5% which was distributed with 36.0 +/- 9.5% for taubound1 and 8.1 +/- 2.6% for taubound2, respectively (n = 8, p < 0.05). The increased binding was selectively found for the receptor-ligand complex with unrestricted lateral mobility (taubound1 of 0.9 +/- 0.1 ms, D1 = 9.1 +/- 0.2 mum(2)/s, n = 8), whereas the binding of ss2AR with hindered lateral mobility (taubound2 of 64.2 +/- 47.6 ms, D2 = 0.15 +/- 0.02 mum(2)/s, n = 8) was not affected. Compared to control cells, a statistically significant increase of 17.5 +/- 6.4% (n = 4, p < 0.05) and 24.2 +/- 5.8% (n = 4, p < 0.001) in the cAMP formation was found for Beta-Hederin pretreated HASM cells after stimulation with 10 muM of terbutaline and simultaneous stimulation with 10 muM terbutaline and 10 muM forskolin, respectively. Within this systematic study focusing on the influence of the ingredients of an ivy leaves dry extract on HASM cells it was possible to identify Beta-Hederin as further component presumably responsible for the beta2-mimetic effects.

The apoptotic effect of D Rhamnose beta-hederin, a novel oleanane-type triterpenoid saponin on breast cancer cells.[Pubmed:24603880]

PLoS One. 2014 Mar 6;9(6):e90848.

There is growing interest in development of natural products as anti-cancer and chemopreventive agents. Many triterpenoids have been proved as potential agents for chemoprevention and therapy of breast cancer. Ginsenosides from ginseng, which mostly belong to dammarane-type triterpenoids, have gained great attention for their anti-breast cancer activity with diverse mechanisms. However, studies of other kinds of triterpenoid saponins on breast cancer are limited. Previously, we purified and identified a novel oleanane-type triterpene saponin named D Rhamnose Beta-Hederin (DRbeta-H) from Clematis ganpiniana, a Chinese traditional anti-tumor herb. In the present study, DRbeta-H showed strong inhibitory activity on the growth of various breast cancer cells and induced apoptosis in these cells. DRbeta-H inhibited PI3K/AKT and activated ERK signaling pathway. PI3K inhibitor LY294002 synergistically enhanced DRbeta-H-induced apoptosis whereas MEK inhibitor U0126 reduced the apoptosis rate. Moreover, DRbeta-H regulated the ratio of pro-apoptotic and anti-apoptotic Bcl-2 family proteins. Furthermore, DRbeta-H induced depolarization of mitochondrial membrane potential which released Apaf-1 and Cytochrome C from the inter membrane space into the cytosol, where they promoted caspase-9 and caspase-3 activation. This is the first report on the pro-apoptotic effects of DRbeta-H, a novel oleanane-type triterpenoid saponin, on breast cancer cells and its comprehensive apoptosis pathways. It implied that oleanane-type triterpenoid saponin DRbeta-H could be a promising candidate for chemotherapy of breast cancer.

Synthesis of beta-hederin and Hederacolchiside A1: triterpenoid saponins bearing a unique cytotoxicity-inducing disaccharide moiety.[Pubmed:16297897]

Carbohydr Res. 2006 Jan 16;341(1):60-7.

A facile synthetic approach toward oleanolic acid glycoside bearing alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl moiety, a unique oligosaccharide that strongly induces antitumor activity of oleanane-type triterpenoid saponins, was developed. Based on this approach Beta-Hederin (oleanolic acid 3-O-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranoside) was efficiently prepared from oleanolic acid through stepwise glycosylation in linear eight steps with 52% overall yield, while Hederacolchiside A1 (oleanolic acid 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->4)]-alpha-L-arabi nopyranoside) in linear 13 steps with 20% overall yield.