A New Saponin (Zygo-albuside D) from Zygophyllum album Roots Triggers Apoptosis in Non-Small Cell Lung Carcinoma (A549 Cells) through CDK-2 Inhibition

Phytochemical study of the ethyl acetate root extract of Zygophyllum album has resulted in the isolation of a new saponin, Zygo-albuside D (1), along with two known compounds; (3-O-[β-D-quinovopyranosyl]-quinovic acid) (2), which is first reported in the root, and catechin (3), first reported in the genus. Their chemical structures were established by NMR and high-resolution mass spectrometry (HRMS). The new saponin (1) exhibited promising cytotoxicity with IC50 values of 3.5 and 5.52 μM on A549 and PC-3 cancer cell lines, respectively, compared to doxorubicin with IC50 values of 9.44 and 11.39 μM on A549 and PC-3 cancer cell lines, respectively. While it had an IC50 value of 46.8 μM against WISH cells. Investigating apoptosis-induction, compound 1 induced total apoptotic cell death in A549 lung cancer cells by 32-fold; 21.53% compared to 0.67% in the untreated control cells. Finally, it upregulated the pro-apoptotic genes and downregulated the antiapoptotic gene using gene expression levels. Compound 1 exhibited remarkable CDK-2 target inhibition by 96.2% with an IC50 value of 117.6 nM compared to Roscovitine. The molecular docking study further confirmed the binding affinity of compound 1 as CDK2 and Bcl2 inhibitors that led to apoptosis induction in A549 cancer cells. Hence, this study highlights the importance of compound 1 in the design of a new anticancer agent with specific mechanisms.

Holospiniferoside: A New Antitumor Cerebroside from The Red Sea Cucumber Holothuria spinifera: In Vitro and In Silico Studies

Chemical investigation of the methanolic extract of the Red Sea cucumber Holothuria spinifera led to the isolation of a new cerebroside, holospiniferoside (1), together with thymidine (2), methyl-α-d-glucopyranoside (3), a new triacylglycerol (4), and cholesterol (5). Their chemical structures were established by NMR and mass spectrometric analysis, including gas chromatography-mass spectrometry (GC-MS) and high-resolution mass spectrometry (HRMS). All the isolated compounds are reported in this species for the first time. Moreover, compound 1 exhibited promising in vitro antiproliferative effect on the human breast cancer cell line (MCF-7) with IC50 of 20.6 µM compared to the IC50 of 15.3 µM for the drug cisplatin. To predict the possible mechanism underlying the cytotoxicity of compound 1, a docking study was performed to elucidate its binding interactions with the active site of the protein Mdm2-p53. Compound 1 displayed an apoptotic activity via strong interaction with the active site of the target protein. This study highlights the importance of marine natural products in the design of new anticancer agents.

New Cytotoxic Cerebrosides from the Red Sea Cucumber Holothuria spinifera Supported by In-Silico Studies

Bioactivity-guided fractionation of a methanolic extract of the Red Sea cucumber Holothuria spinifera and LC-HRESIMS-assisted dereplication resulted in the isolation of four compounds, three new cerebrosides, spiniferosides A (1), B (2), and C (3), and cholesterol sulfate (4). The chemical structures of the isolated compounds were established on the basis of their 1D NMR and HRMS spectral data. Metabolic profiling of the H. spinifera extract indicated the presence of diverse secondary metabolites, mostly hydroxy fatty acids, diterpenes, triterpenes, and cerebrosides. The isolated compounds were tested for their in vitro cytotoxicities against the breast adenocarcinoma MCF-7 cell line. Compounds 1, 2, 3, and 4 displayed promising cytotoxic activities against MCF-7 cells, with IC50 values of 13.83, 8.13, 8.27, and 35.56 µM, respectively, compared to that of the standard drug doxorubicin (IC50 8.64 µM). Additionally, docking studies were performed for compounds 1, 2, 3, and 4 to elucidate their binding interactions with the active site of the SET protein, an inhibitor of protein phosphatase 2A (PP2A), which could explain their cytotoxic activity. This study highlights the important role of these metabolites in the defense mechanism of the sea cucumber against fouling organisms and the potential uses of these active molecules in the design of new anticancer agents.