@article{EltamanyAbdelmohsenHaletal.2021, author = {Eltamany, Enas E. and Abdelmohsen, Usama Ramadan and Hal, Dina M. and Ibrahim, Amany K. and Hassanean, Hashim A. and Abdelhameed, Reda F. A. and Temraz, Tarek A. and Hajjar, Dina and Makki, Arwa A. and Hendawy, Omnia Magdy and AboulMagd, Asmaa M. and Youssif, Khayrya A. and Bringmann, Gerhard and Ahmed, Safwat A.}, title = {Holospiniferoside: A New Antitumor Cerebroside from The Red Sea Cucumber Holothuria spinifera: In Vitro and In Silico Studies}, series = {Molecules}, volume = {26}, journal = {Molecules}, number = {6}, issn = {1420-3049}, doi = {10.3390/molecules26061555}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-234058}, year = {2021}, abstract = {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 IC\(_{50}\) 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.}, language = {en} } @article{AbdelhameedHabibEltahawyetal.2020, author = {Abdelhameed, Reda F. A. and Habib, Eman S. and Eltahawy, Nermeen A. and Hassanean, Hashim A. and Ibrahim, Amany K. and Mohammed, Anber F. and Fayez, Shaimaa and Hayallah, Alaa M. and Yamada, Koji and Behery, Fathy A. and Al-Sanea, Mohammad M. and Alzarea, Sami I. and Bringmann, Gerhard and Ahmed, Safwat A. and Abdelmohsen, Usama Ramadan}, title = {New cytotoxic natural products from the Red Sea sponge Stylissa carteri}, series = {Marine Drugs}, volume = {18}, journal = {Marine Drugs}, number = {5}, issn = {1660-3397}, doi = {10.3390/md18050241}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-205795}, year = {2020}, abstract = {Bioactivity-guided isolation supported by LC-HRESIMS metabolic profiling led to the isolation of two new compounds, a ceramide, stylissamide A (1), and a cerebroside, stylissoside A (2), from the methanol extract of the Red Sea sponge Stylissa carteri. Structure elucidation was achieved using spectroscopic techniques, including 1D and 2D NMR and HRMS. The bioactive extract's metabolomic profiling showed the existence of various secondary metabolites, mainly oleanane-type saponins, phenolic diterpenes, and lupane triterpenes. The in vitro cytotoxic activity of the isolated compounds was tested against two human cancer cell lines, MCF-7 and HepG2. Both compounds, 1 and 2, displayed strong cytotoxicity against the MCF-7 cell line, with IC\(_{50}\) values at 21.1 ± 0.17 µM and 27.5 ± 0.18 µM, respectively. They likewise showed a promising activity against HepG2 with IC\(_{50}\) at 36.8 ± 0.16 µM for 1 and IC\(_{50}\) 30.5 ± 0.23 µM for 2 compared to the standard drug cisplatin. Molecular docking experiments showed that 1 and 2 displayed high affinity to the SET protein and to inhibitor 2 of protein phosphatase 2A (I2PP2A), which could be a possible mechanism for their cytotoxic activity. This paper spreads light on the role of these metabolites in holding fouling organisms away from the outer surface of the sponge, and the potential use of these defensive molecules in the production of novel anticancer agents.}, language = {en} } @article{AbdelhameedEltamanyHaletal.2020, author = {Abdelhameed, Reda F. A. and Eltamany, Enas E. and Hal, Dina M. and Ibrahim, Amany K. and AboulMagd, Asmaa M. and Al-Warhi, Tarfah and Youssif, Khayrya A. and Abd El-kader, Adel M. and Hassanean, Hashim A. and Fayez, Shaimaa and Bringmann, Gerhard and Ahmed, Safwat A. and Abdelmohsen, Usama Ramadan}, title = {New cytotoxic cerebrosides from the Red Sea cucumber Holothuria spinifera supported by in-silico studies}, series = {Marine Drugs}, volume = {18}, journal = {Marine Drugs}, number = {8}, issn = {1660-3397}, doi = {10.3390/md18080405}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-211089}, year = {2020}, abstract = {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 IC\(_{50}\) values of 13.83, 8.13, 8.27, and 35.56 µM, respectively, compared to that of the standard drug doxorubicin (IC\(_{50}\) 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.}, language = {en} }