Suchergebnisse

The Mediterranean marine sponge Crambe crambe is the source of two families of guanidine alkaloids known as crambescins and crambescidins. Some of the biological effects of crambescidins have been previously reported while crambescins have undergone little study. Taking this into account, we performed comparative transcriptome analysis to examine the effect of crambescin-C1 (CC1) on human tumor hepatocarcinoma cells HepG2 followed by validation experiments to confirm its predicted biological activities. We report herein that, while crambescin-A1 has a minor effect on these cells, CC1 protects them against oxidative injury by means of metallothionein induction even at low concentrations. Additionally, at high doses, CC1 arrests the HepG2 cell cycle in G0/G1 and thus inhibits tumor cell proliferation. The findings presented here provide the first detailed approach regarding the different effects of crambescins on tumor cells and provide a basis for future studies on other possible cellular mechanisms related to these bioactivities ; FEDER cofunded-grants. CDTI and Technological Funds, supported by Ministerio de Economía y Competitividad, AGL2012-40185-CO2-01 and Consellería de Cultura, Educación e Ordenación Universitaria, GRC2013-016, and by Axencia Galega de Innovación, Spain, ITC-20133020 SINTOX, IN852A 2013/16-3 MYTIGAL. CDTIunderISIP Programme, Spain, IDI-20130304 APTAFOOD. European Union's 7th Framework Programme managed by Research Executive Agency (FP7/2007-2013) under grant agreement Nos. 265409 µAQUA, 315285 CIGUATOOLS and 312184 PHARMASEA ; SI

The marine environment constitutes an extraordinary resource for the discovery of new therapeutic agents. In the present manuscript we studied the effect of 3 different sponge derived guanidine alkaloids, crambescidine-816, -830, and -800. We show that these compounds strongly inhibit tumor cell proliferation by down-regulating cyclin-dependent kinases 2/6 and cyclins D/A expression while up-regulating the cell cyclin-dependent kinase inhibitors -2A, -2D and -1A. We also show that these guanidine compounds disrupt tumor cell adhesion and cytoskeletal integrity promoting the activation of the intrinsic apoptotic signaling, resulting in loss of mitochondrial membrane potential and concomitant caspase-3 cleavage and activation. The crambescidin 816 anti-tumor effect was fnally assayed in a zebrafish xenotransplantation model confirming its potent antitumor activity against colorectal carcinoma in vivo. Considering these results crambescidins could represent promising natural anticancer agents and therapeutic tools ; The research leading to these results has received funding from the following FEDER cofunded-grants. From CDTI and Technological Funds, supported by Ministerio de Economía y Competitividad, AGL2012-40185-CO2-01, AGL2014-58210-R, and Consellería de Cultura, Educación e Ordenación Universitaria, GRC2013-016. From CDTI under ISIP Programme, Spain, IDI-20130304 APTAFOOD. From the European Union's Seventh Framework Programme managed by REA – Research Executive Agency (FP7/2007-2013) under grant agreement 312184 PHARMASEA. M.R.S. is an I2C predoctoral fellow. From CAPES Foundation, Brazil (scholarship process: BEX 10184-13-9) ; SI

In 2012, Tetrodotoxin (TTX) was identified in mussels and linked to the presence of Prorocentrum minimum (P. minimum) in Greece. The connexion between TTX and P. minimum was further studied in this paper. First, the presence of TTX-producer bacteria, Vibrio and Pseudomonas spp, was confirmed in Greek mussels. In addition these samples showed high activity as inhibitors of sodium currents (INa). P. minimum was before associated with neurotoxic symptoms, however, the nature and structure of toxins produced by this dinoflagellate remains unknown. Three P. minimum strains, ccmp1529, ccmp2811 and ccmp2956, growing in different conditions of temperature, salinity and light were used to study the production of toxic compounds. Electrophysiological assays showed no effect of ccmp2811 strain on INa, while ccmp1529 and ccmp2956 strains were able to significantly reduce INa in the same way as TTX. In these samples two new compounds, m/z 265 and m/z 308, were identified and characterized by liquid chromatography tandem high-resolution mass spectrometry. Besides, two TTX-related bacteria, Roseobacter and Vibrio sp, were observed. These results show for the first time that P. minimum produce TTX-like compounds with a similar ion pattern and C9-base to TTX analogues and with the same effect on INa ; Inés Rodríguez is supported by a fellowship from Subprograma de Formación de Personal Investigador MINECO (AGL2012-40185-CO2-01), Spain. The research leading to these results has received funding from the following FEDER cofunded-grants. From CDTI and Technological Funds, supported by Ministerio de Economía y Competitividad, AGL2012-40185-CO2-01, AGL2014-58210-R, and Consellería de Cultura, Educación e Ordenación Universitaria, GRC2013-016. From CDTI under ISIP Programme, Spain, IDI-20130304 APTAFOOD. From the European Union's Seventh Framework Programme managed by REA – Research Executive Agency (FP7/2007-2013) under grant agreement 312184 PHARMASEA. ; SI