1.A New Cytotoxic Steroidal Glycoalkaloid from the Methanol Extract of Blumea lacera Leaves.
Akter R1, Uddin SJ, Tiralongo J, Grice ID, Tiralongo E. J Pharm Pharm Sci. 2015;18(4):616-33.
PURPOSE: Blumea lacera (B. lacera) (Asteraceae) is a well-known Bangladeshi medicinal plant. This study aimed to identify and characterize constituents associated with the significant cytotoxic activity of this plant that we reported previously. Here, we describe the isolation and characterization of a new steroidal glycoalkaloid (SGA) 1, the evaluation of its cytotoxic activity, apoptotic potential, and effect on cell cycle in comparison to analogous steroidal glycoalkaloids (SGAs).
2.Bioassay-guided fractionation of extracts from Easter lily (Lilium longiflorum) flowers reveals unprecedented structural variability of steroidal glycoalkaloids.
Uhlig S1, Hussain F2, Wisløff H2. Toxicon. 2014 Dec 15;92:42-9. doi: 10.1016/j.toxicon.2014.09.004. Epub 2014 Sep 28.
Several Lilium species are nephrotoxic in cats (Felis silvestris catus), among them Easter lilies (Lilium longiflorum). Although clinical trials have been carried out, the causative toxic phytochemicals have not yet been identified. We thus aimed to determine the toxic constituents of Easter lily flowers applying a bioassay-guided approach based on a feline kidney cell line model. The bioassay-guided fractionation traced the observed cytotoxicity to a complex mixture of compounds that were tentatively identified as steroidal glycoalkaloids of the solasodine-type, based on multiple-fragmentation ion trap and high-resolution mass spectrometry. The glycoalkaloids in the active fraction possessed trisaccharide chains, and at least 16 different congeners could be separated using liquid chromatography-mass spectrometry. The two principal compounds were solasodine trisaccharides containing two hexose and one deoxy-hexose unit. In the remaining 14 analogues, one or two of the hydroxyl groups of the second hexose from the aglycone were acetylated.
3.Comparative interactions of withanolides and sterols with two members of sterol glycosyltransferases from Withania somnifera.
Pandey V1,2, Dhar YV3, Gupta P4, Bag SK5, Atri N6, Asif MH7, Trivedi PK8, Misra P9. BMC Bioinformatics. 2015 Apr 16;16:120. doi: 10.1186/s12859-015-0563-7.
BACKGROUND: Sterol glycosyltransferases (SGTs) are ubiquitous but one of the most diverse group of enzymes of glycosyltransferases family. Members of this family modulate physical and chemical properties of secondary plant products important for various physiological processes. The role of SGTs has been demonstrated in the biosynthesis of pharmaceutically important molecules of medicinal plants like Withania somnifera.
4.Chemistry and anticarcinogenic mechanisms of glycoalkaloids produced by eggplants, potatoes, and tomatoes.
Friedman M1. J Agric Food Chem. 2015 Apr 8;63(13):3323-37. doi: 10.1021/acs.jafc.5b00818. Epub 2015 Mar 30.
Inhibition of cancer can occur via apoptosis, a genetically directed process of cell self-destruction that involves numerous biomarkers and signaling pathways. Glycoalkaloids are nitrogen-containing secondary plant metabolites found in numerous Solanaceous plants including eggplants, potatoes, and tomatoes. Exposure of cancer cells to glycoalkaloids produced by eggplants (α-solamargine and α-solasonine), potatoes (α-chaconine and α-solanine), and tomatoes (α-tomatine) or their hydrolysis products (mono-, di-, and trisaccharide derivatives and the aglycones solasodine, solanidine, and tomatidine) inhibits the growth of the cells in culture (in vitro) as well as tumor growth in vivo. This overview comprehensively surveys and consolidates worldwide efforts to define the following aspects of these natural compounds: (a) their prevalence in the three foods; (b) their chemistry and structure-activity relationships; (c) the reported factors (biomarkers, signaling pathways) associated with apoptosis of bone, breast, cervical, colon, gastric, glioblastoma, leukemia, liver, lung, lymphoma, melanoma, pancreas, prostate, and squamous cell carcinoma cell lines in vitro and the in vivo inhibition of tumor formation and growth in fish and mice and in human skin cancers; and (d) future research needs.