Click
here to close Hello! We notice that
you are using Internet Explorer, which is not supported by Echinobase
and may cause the site to display incorrectly. We suggest using a
current version of Chrome,
FireFox,
or Safari.
Mar Drugs
2014 Jul 07;127:4069-85. doi: 10.3390/md12074069.
Show Gene links
Show Anatomy links
Ovothiol isolated from sea urchin oocytes induces autophagy in the Hep-G2 cell line.
Russo GL
,
Russo M
,
Castellano I
,
Napolitano A
,
Palumbo A
.
Abstract
Ovothiols are histidine-derived thiols isolated from sea urchin eggs, where they play a key role in the protection of cells toward the oxidative burst associated with fertilization by controlling the cellular redox balance and recycling oxidized glutathione. In this study, we show that treatment of a human liver carcinoma cell line, Hep-G2, with ovothiol A, isolated from Paracentrotus lividus oocytes, results in a decrease of cell proliferation in a dose-dependent manner. The activation of an autophagic process is revealed by phase contrast and fluorescence microscopy, together with the expression of the specific autophagic molecular markers, LC3 II and Beclin-1. The effect of ovothiol is not due to its antioxidant capacity or to hydrogen peroxide generation. The concentration of ovothiol A in the culture media, as monitored by HPLC analysis, decreased by about 24% within 30 min from treatment. The proliferation of normal human embryonic lung cells is not affected by ovothiol A. These results hint at ovothiol as a promising bioactive molecule from marine organisms able to inhibit cell proliferation in cancer cells.
Figure 2. Analysis of ovothiol A purified from sea urchins. (A) Elutographic profile of ovothiol A obtained by ion exchange chromatography purification of the sea urchin extracts. Detection at 254 (black trace) and 280 (red trace) nm. Inset: UV-Vis absorption spectrum of ovothiol A; (B) Mass spectrum of ovothiol A.
Figure 4. Ovothiol A induces autophagy in Hep-G2 cells. (A) After stimulation for 24 h with increasing doses of ovothiol (50â200 μM) or positive controls (quercetin, sorafenib and rapamycin, at 25, 20 and 1 μM, respectively), autophagy was detected and measured using a specific kit, as described in the Materials and Methods Section. At least 100 cells in two independent fields were counted using a phase contrast microscope, and the presence of positive autophagic cells was evaluated by fluorescence in the same fields. The figure shows representative images of cells treated with ovothiol, quercetin, sorafenib and rapamycin at the indicated concentrations (optical microscope Axiovert 200 M Zeiss; 400Ã, phase contrast in aâg and fluorescence FITC in aââgâ). Numbers on the bottom of panels aââgâ indicate percentage (means ± SD compared to untreated cells of two separate experiments) of positive autophagic cells; (B) Western blot analysis of LC3 I, LC3 II and Beclin-1 expression in Hep-G2 cells treated for 24 h with indicated doses of ovothiol, quercetin and sorafenib. Bands are representative of one out of three separate experiments performed; (C) Densitometric analysis of blots shown in Panel B (optical density of LC3 II/α-tubulin, left and Beclin-1/α-tubulin, right). Values are presented as the mean ± SD Symbols indicate significance: p < 0.05 (*), p < 0.01 (**), p < 0.001 (***) with respect to untreated cells.
Figure 6. Ovothiol A levels decrease in the incubation medium. The HPLC trace of the Hep-G2 culture medium following treatment with 200 μM ovothiol; (A) T = 0 min; (B) T = 30 min. Detection at 254 (black trace) and 280 (red trace) nm. Highlighted is the peak corresponding to ovothiol A.
Figure 8. Ovothiol does not induce cytotoxicity in WI-38 cells. Cells were treated for 24â48 h with increasing doses of ovothiol A (10â200 μM), and cell viability was measured by the crystal violet assay. Values are presented as the mean ± SD compared to untreated cells.
Ariyanayagam,
Ovothiol and trypanothione as antioxidants in trypanosomatids.
2001, Pubmed
Ariyanayagam,
Ovothiol and trypanothione as antioxidants in trypanosomatids.
2001,
Pubmed
Bailly,
Antioxidant actions of ovothiol-derived 4-mercaptoimidazoles: glutathione peroxidase activity and protection against peroxynitrite-induced damage.
2000,
Pubmed
Braunshausen,
Identification and characterization of the first ovothiol biosynthetic enzyme.
2011,
Pubmed
Castellano,
Glutathionylation of the iron superoxide dismutase from the psychrophilic eubacterium Pseudoalteromonas haloplanktis.
2008,
Pubmed
Castellano,
Rat mitochondrial manganese superoxide dismutase: amino acid positions involved in covalent modifications, activity, and heat stability.
2009,
Pubmed
Choi,
Autophagy in human health and disease.
2013,
Pubmed
Gibson,
Investigating the role of reactive oxygen species in regulating autophagy.
2013,
Pubmed
Halliwell,
Measuring reactive species and oxidative damage in vivo and in cell culture: how should you do it and what do the results mean?
2004,
Pubmed
Halliwell,
The wanderings of a free radical.
2009,
Pubmed
Hand,
Biological chemistry of naturally occurring thiols of microbial and marine origin.
2005,
Pubmed
HAYFLICK,
The serial cultivation of human diploid cell strains.
1961,
Pubmed
Holler,
Ovothiols as free-radical scavengers and the mechanism of ovothiol-promoted NAD(P)H-O2 oxidoreductase activity.
1990,
Pubmed
Ianora,
The relevance of marine chemical ecology to plankton and ecosystem function: an emerging field.
2011,
Pubmed
Kang,
The Beclin 1 network regulates autophagy and apoptosis.
2011,
Pubmed
Kim,
Determination of cytotoxicity attributed to multiwall carbon nanotubes (MWCNT) in normal human embryonic lung cell (WI-38) line.
2010,
Pubmed
Kimura,
Chloroquine in cancer therapy: a double-edged sword of autophagy.
2013,
Pubmed
Klappan,
Proteasome inhibition by quercetin triggers macroautophagy and blocks mTOR activity.
2012,
Pubmed
Klionsky,
Guidelines for the use and interpretation of assays for monitoring autophagy.
2012,
Pubmed
Knowles,
Human hepatocellular carcinoma cell lines secrete the major plasma proteins and hepatitis B surface antigen.
1980,
Pubmed
Lorin,
Autophagy regulation and its role in cancer.
2013,
Pubmed
Lozy,
Autophagy and cancer cell metabolism.
2012,
Pubmed
Maiuri,
Self-eating and self-killing: crosstalk between autophagy and apoptosis.
2007,
Pubmed
Mashabela,
Substrate specificity of an oxygen dependent sulfoxide synthase in ovothiol biosynthesis.
2013,
Pubmed
Namba,
Carcinogenesis in tissue culture. 29: Neoplastic transformation of a normal human diploid cell strain, WI-38, with Co-60 gamma rays.
1978,
Pubmed
Nelson,
Exploiting different ways to die.
2004,
Pubmed
Nourooz-Zadeh,
Measurement of plasma hydroperoxide concentrations by the ferrous oxidation-xylenol orange assay in conjunction with triphenylphosphine.
1994,
Pubmed
Orlikova,
Anti-inflammatory and anticancer drugs from nature.
2014,
Pubmed
Ouyang,
Programmed cell death pathways in cancer: a review of apoptosis, autophagy and programmed necrosis.
2012,
Pubmed
Rubinsztein,
Autophagy modulation as a potential therapeutic target for diverse diseases.
2012,
Pubmed
Sawadogo,
A survey of marine natural compounds and their derivatives with anti-cancer activity reported in 2011.
2013,
Pubmed
Seebeck,
Thiohistidine biosynthesis.
2013,
Pubmed
Selman-Reimer,
L-1-N-methyl-4-mercaptohistidine disulfide, a potential endogenous regulator in the redox control of chloroplast coupling factor 1 in Dunaliella.
1991,
Pubmed
Serrano,
Oncogenic ras provokes premature cell senescence associated with accumulation of p53 and p16INK4a.
1997,
Pubmed
Spagnuolo,
Dietary polyphenols in cancer prevention: the example of the flavonoid quercetin in leukemia.
2012,
Pubmed
Spies,
Thiols of intracellular pathogens. Identification of ovothiol A in Leishmania donovani and structural analysis of a novel thiol from Mycobacterium bovis.
1994,
Pubmed
Steenkamp,
Identification of a major low-molecular-mass thiol of the trypanosomatid Crithidia fasciculata as ovothiol A. Facile isolation and structural analysis of the bimane derivative.
1994,
Pubmed
Tai,
Mcl-1-dependent activation of Beclin 1 mediates autophagic cell death induced by sorafenib and SC-59 in hepatocellular carcinoma cells.
2013,
Pubmed
Tanida,
LC3 and Autophagy.
2008,
Pubmed
Tedesco,
Dealcoholated red wine induces autophagic and apoptotic cell death in an osteosarcoma cell line.
2013,
Pubmed
Tedesco,
Commentary on 'resveratrol commonly displays hormesis: occurrence and biomedical significance'.
2010,
Pubmed
Turner,
Ovothiol: a novel thiohistidine compound from sea urchin eggs that confers NAD(P)H-O2 oxidoreductase activity on ovoperoxidase.
1986,
Pubmed
,
Echinobase
Turner,
Ovothiol replaces glutathione peroxidase as a hydrogen peroxide scavenger in sea urchin eggs.
1988,
Pubmed
,
Echinobase
Vamecq,
Potent mammalian cerebroprotection and neuronal cell death inhibition are afforded by a synthetic antioxidant analogue of marine invertebrate cell protectant ovothiols.
2003,
Pubmed
Zhang,
Plant natural compounds: targeting pathways of autophagy as anti-cancer therapeutic agents.
2012,
Pubmed
Zhou,
Small-molecule regulators of autophagy and their potential therapeutic applications.
2013,
Pubmed
Zoete,
4-Mercaptoimidazoles derived from the naturally occurring antioxidant ovothiols 1. Antioxidant properties.
2000,
Pubmed
Zoete,
4-Mercaptoimidazoles derived from the naturally occurring antioxidant ovothiols 2. Computational and experimental approach of the radical scavenging mechanism.
2000,
Pubmed