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Yu X, Jiang K, Zhang W, Dong S, Wu Y, Zhang G, Wu S, Chen T, Liu G. Purification, Identification, and Properties of a Novel Carotenoid Produced by Arthrobacter sp. QL17 Isolated from Mount Qomolangma. Antioxidants (Basel) 2022; 11:antiox11081493. [PMID: 36009212 PMCID: PMC9404904 DOI: 10.3390/antiox11081493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 07/26/2022] [Accepted: 07/27/2022] [Indexed: 02/04/2023] Open
Abstract
The genus Arthrobacter is a source of many natural products that are critical in the development of new medicines. Here, we isolated a novel carotenoid from Arthrobacter sp. QL17 and characterized its properties. The carotenoid was extracted with methanol, and purified by column chromatography and semi-preparative HPLC. Based on micrOTOF-Q and NMR analyses, the pigment was chemically characterized as 2,2′-((((1E,3E,5E,7E,9E,11E,13E,15E,17E,19E)-3,7,14,18-tetramethylicosa-1,3,5,7,9,11,13,15,17,19-decaene-1,20-diyl)bis(2,2,4-trimethylcyclohex-3-ene-3,1-diyl)) bis(ethan-2-yl-1-ylidene))bi(propane-1,3-diol), and named arthroxanthin. The biological activities of arthroxanthin were evaluated with DPPH, ABTS and MTT assays. Arthroxanthin exhibited excellent radical scavenging properties, as shown for 2, 20-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-n-(3, 2-ethyl-benzothiazole-6-sulfonic acid) ammonium salt (ABTS), respectively, with IC50s of 69.8 and 21.5 µg/mL. It also showed moderate anticancer activities against HepG2, Hela, MDAB-231, SW480, and MKN-45 with IC50 values of 107.6, 150.4, 143.4, 195.9, and 145.5 μg/mL, respectively. Therefore, arthroxanthin derived from Arthrobacter sp. QL17 may be a potent antioxidant and anticancer agent for food and pharmaceutical use.
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Affiliation(s)
- Xue Yu
- Key Laboratory of Desert and Desertification, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730030, China;
- Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Lanzhou 730030, China; (Y.W.); (G.Z.); (S.W.); (T.C.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kan Jiang
- Agronomy College, Gansu Agricultural University, Lanzhou 730070, China;
| | - Wei Zhang
- Key Laboratory of Desert and Desertification, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730030, China;
- Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Lanzhou 730030, China; (Y.W.); (G.Z.); (S.W.); (T.C.)
- Correspondence: (W.Z.); (G.L.)
| | - Shuqing Dong
- CAS Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730030, China;
| | - Yujie Wu
- Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Lanzhou 730030, China; (Y.W.); (G.Z.); (S.W.); (T.C.)
- University of Chinese Academy of Sciences, Beijing 100049, China
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730030, China
| | - Gaosen Zhang
- Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Lanzhou 730030, China; (Y.W.); (G.Z.); (S.W.); (T.C.)
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730030, China
| | - Shiyu Wu
- Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Lanzhou 730030, China; (Y.W.); (G.Z.); (S.W.); (T.C.)
| | - Tuo Chen
- Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Lanzhou 730030, China; (Y.W.); (G.Z.); (S.W.); (T.C.)
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730030, China
| | - Guangxiu Liu
- Key Laboratory of Desert and Desertification, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730030, China;
- Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Lanzhou 730030, China; (Y.W.); (G.Z.); (S.W.); (T.C.)
- Correspondence: (W.Z.); (G.L.)
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Enhancing the bioaccessibility of lycopene from tomato processing byproducts via supercritical carbon dioxide extraction. Curr Res Food Sci 2022; 5:553-563. [PMID: 35309261 PMCID: PMC8928129 DOI: 10.1016/j.crfs.2022.01.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 01/05/2022] [Accepted: 01/25/2022] [Indexed: 11/21/2022] Open
Abstract
Tomato peel and seed from tomato processing industry are treated as waste; however, they contain lycopene, a high-value bioactive compound. In this study, lycopene was extracted from tomato peel and seed using supercritical carbon dioxide (SC–CO2) and hexane, and the bioaccessibilities of lycopene in the SC-CO2- and hexane-extracted oleoresins were investigated for the first time. The (Z)-lycopene content of the SC-CO2-extracted oleoresin (69%) was higher than that of hexane-extracted oleoresin (45%). Separation of the insoluble fraction from the oleoresins increased the (Z)-lycopene contents of the SC-CO2- and hexane-extracted oil fractions to 80% and 49%, respectively. The bioaccessibility of total-lycopene in the oleoresins was increased by 3.3-fold via SC-CO2 extraction, which was attributed to higher (Z)-lycopene content, and small-sized uniform distribution of lycopene in the oleoresin. SC-CO2 extraction is not only a green method for extraction of bioactive compounds, but also has the potential to improve health benefits of bioactive compounds. Lycopene-rich oleoresins were extracted from tomato processing byproducts. Supercritical carbon dioxide (SC–CO2) and hexane extractions were compared. SC-CO2 extraction increased the cis-lycopene content of the oleoresins up to 69%. SC-CO2-extracted oleoresins contained uniform well-dispersed lycopene. The bioaccessibility of lycopene was enhanced by 3.3-fold by SC-CO2 ext.
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Abstract
Tomato processing leads to the production of considerable amounts of residues, mainly in the form of tomato skins, seeds and vascular tissues, which still contain bioactive molecules of interest for food, pharmaceutical and nutraceutical industries. These include carotenoids, such as lycopene and β-carotene, tocopherols and sitosterols, among others. Supercritical fluid extraction is well positioned for the valorization of tomato residues prior to disposal, because it remains an environmentally safe extraction process, especially when using carbon dioxide as the solvent. In this article, we provide an extensive literature overview of the research on the supercritical fluid extraction of tomato residues. We start by identifying the most relevant extractables present in tomatoes (e.g., lycopene) and their main bioactivities. Then, the main aspects affecting the extraction performance are covered, starting with the differences between tomato matrixes (e.g., seeds, skins and pulp) and possible pretreatments to enhance extraction (e.g., milling, drying and enzymatic digestion). Finally, the effects of extraction conditions, such as pressure, temperature, cosolvent, flow rate and time, are discussed.
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Romano R, Aiello A, Pizzolongo F, Rispoli A, De Luca L, Masi P. Characterisation of oleoresins extracted from tomato waste by liquid and supercritical carbon dioxide. Int J Food Sci Technol 2020. [DOI: 10.1111/ijfs.14597] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Raffaele Romano
- Department of Agricultural Sciences University of Naples Federico II via Università 100 80055 Portici Italy
| | - Alessandra Aiello
- Department of Agricultural Sciences University of Naples Federico II via Università 100 80055 Portici Italy
| | - Fabiana Pizzolongo
- Department of Agricultural Sciences University of Naples Federico II via Università 100 80055 Portici Italy
| | - Andrea Rispoli
- Department of Agricultural Sciences University of Naples Federico II via Università 100 80055 Portici Italy
| | - Lucia De Luca
- Department of Agricultural Sciences University of Naples Federico II via Università 100 80055 Portici Italy
| | - Paolo Masi
- CAISIAL University of Naples Federico II Via Università 133 80055 Portici Italy
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Pro-Apoptotic Effect of Grape Seed Extract on MCF-7 Involves Transient Increase of Gap Junction Intercellular Communication and Cx43 Up-Regulation: A Mechanism of Chemoprevention. Int J Mol Sci 2019; 20:ijms20133244. [PMID: 31269652 PMCID: PMC6651466 DOI: 10.3390/ijms20133244] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 06/25/2019] [Accepted: 06/28/2019] [Indexed: 02/06/2023] Open
Abstract
Growing evidence suggests dietary antioxidants reduce the risk of several cancers. Grape seeds extracts (GSE) are a rich source of polyphenols known to have antioxidant, chemopreventive and anticancer properties. Herein, we investigated the in vitro effects and putative action mechanisms of a grape seed extract (GSE) on human breast cancer cells (MCF-7). The effects of GSE were evaluated on cell proliferation, apoptosis and gap-junction-mediated cell-cell communications (GJIC), as basal mechanism involved in the promotion stage of carcinogenesis. GSE (0.05-100 μg/mL) caused a significant dose- and time-dependent inhibition of MCF-7 viability and induced apoptotic cell death, as detected by Annexin-V/Propidium Iodide. Concurrently, GSE induced transient but significant enhancement of GJIC in non-communicating MCF-7 cells, as demonstrated by the scrape-loading/dye-transfer (SL/DT) assay and an early and dose-dependent re-localization of the connexin-43 (Cx43) proteins on plasma membranes, as assayed by immunocytochemistry. Finally, real-time-PCR has evidenced a significant increase in cx43 mRNA expression. The results support the hypothesis that the proliferation inhibition and pro-apoptotic effect of GSE against this breast cancer cell model are mediated by the GJIC improvement via re-localization of Cx43 proteins and up-regulation of cx43 gene, and provide further insight into the action mechanisms underlying the health-promoting action of dietary components.
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Hou J, Cui HL. In Vitro Antioxidant, Antihemolytic, and Anticancer Activity of the Carotenoids from Halophilic Archaea. Curr Microbiol 2017; 75:266-271. [DOI: 10.1007/s00284-017-1374-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 10/10/2017] [Indexed: 10/18/2022]
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Babica P, Čtveráčková L, Lenčešová Z, Trosko JE, Upham BL. Chemopreventive Agents Attenuate Rapid Inhibition of Gap Junctional Intercellular Communication Induced by Environmental Toxicants. Nutr Cancer 2016; 68:827-37. [PMID: 27266532 DOI: 10.1080/01635581.2016.1180409] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Altered gap junctional intercellular communication (GJIC) has been associated with chemical carcinogenesis, where both chemical tumor promoters and chemopreventive agents (CPAs) are known to conversely modulate GJIC. The aim of this study was to investigate whether attenuation of chemically inhibited GJIC represents a common outcome induced by different CPAs, which could be effectively evaluated using in vitro methods. Rat liver epithelial cells WB-F344 were pretreated with a CPA for either 30 min or 24 h, and then exposed to GJIC-inhibiting concentration of a selected tumor promoter or environmental toxicant [12-O-tetradecanoylphorbol-13-acetate (TPA), lindane, fluoranthene, 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT), perfluorooctanoic acid (PFOA), or pentachlorophenol]. Out of nine CPAs tested, quercetin and silibinin elicited the most pronounced effects, preventing the dysregulation of GJIC by all the GJIC inhibitors, but DDT. Metformin and curcumin attenuated the effects of three GJIC inhibitors, whereas the other CPAs prevented the effects of two (diallyl sulfide, emodin) or one (indole-3-carbinol, thymoquinone) GJIC inhibitor. Significant attenuation of chemically induced inhibition of GJIC was observed in 27 (50%) out of 54 possible combinations of nine CPAs and six GJIC inhibitors. Our data demonstrate that in vitro evaluation of GJIC can be used as an effective screening tool for identification of chemicals with potential chemopreventive activity.
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Affiliation(s)
- Pavel Babica
- a Department of Experimental Phycology and Ecotoxicology , Institute of Botany of the ASCR , Brno , Czech Republic.,b RECETOX - Research Centre for Toxic Compounds in the Environment, Faculty of Science, Masaryk University , Brno , Czech Republic
| | - Lucie Čtveráčková
- a Department of Experimental Phycology and Ecotoxicology , Institute of Botany of the ASCR , Brno , Czech Republic.,b RECETOX - Research Centre for Toxic Compounds in the Environment, Faculty of Science, Masaryk University , Brno , Czech Republic
| | - Zuzana Lenčešová
- a Department of Experimental Phycology and Ecotoxicology , Institute of Botany of the ASCR , Brno , Czech Republic.,b RECETOX - Research Centre for Toxic Compounds in the Environment, Faculty of Science, Masaryk University , Brno , Czech Republic
| | - James E Trosko
- c Department of Pediatrics and Human Development & Institute for Integrative Toxicology, Michigan State University , Michigan , USA
| | - Brad L Upham
- c Department of Pediatrics and Human Development & Institute for Integrative Toxicology, Michigan State University , Michigan , USA
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Abbes M, Baati H, Guermazi S, Messina C, Santulli A, Gharsallah N, Ammar E. Biological properties of carotenoids extracted from Halobacterium halobium isolated from a Tunisian solar saltern. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 13:255. [PMID: 24090008 PMCID: PMC3853157 DOI: 10.1186/1472-6882-13-255] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Accepted: 09/30/2013] [Indexed: 01/11/2023]
Abstract
Background Bioactive molecules have received increasing attention due to their nutraceutical attributes and anticancer, antioxidant, antiproliferative and apoptosis-inducing properties. This study aimed to investigate the biological properties of carotenoids extracted from Archaea. Methods Halophilic Archaea strains were isolated from the brine of a local crystallizer pond (TS7) of a solar saltern at Sfax, Tunisia. The most carotenoid-producing strain (M8) was investigated on heptoma cell line (HepG2), and its viability was assessed by the MTT-test. The cells were incubated with different sub-lethal extract rates, with carotenoid concentrations ranging from 0.2 to 1.5 μM. Antioxidant activity was evaluated through exposing the cells to sub-lethal extract concentrations for 24 hours and then to oxidative stress induced by 60 μM arachidonic acid and 50 μM H2O2. Results Compared to non-treated cells, bacterial carotenoid extracts inhibited HepG2 cell viability (50%). A time and dose effect was observed, with cell viability undergoing a significant (P < 0.05) decrease with extract concentration. After exposure to oxidative stress, control cells underwent a significant (P < 0.05) decrease in viability as compared to the non-treated cells. Conclusions The bacterial extracts under investigation were noted to exhibit the strongest free radical scavenging activity with high carotenoid concentrations. The carotenoid extract also showed significant antiproliferative activity against HepG2 human cancer cell lines.
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Leone A, Lecci RM, Durante M, Piraino S. Extract from the zooxanthellate jellyfish Cotylorhiza tuberculata modulates gap junction intercellular communication in human cell cultures. Mar Drugs 2013; 11:1728-62. [PMID: 23697954 PMCID: PMC3707171 DOI: 10.3390/md11051728] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 04/24/2013] [Accepted: 04/25/2013] [Indexed: 12/13/2022] Open
Abstract
On a global scale, jellyfish populations in coastal marine ecosystems exhibit increasing trends of abundance. High-density outbreaks may directly or indirectly affect human economical and recreational activities, as well as public health. As the interest in biology of marine jellyfish grows, a number of jellyfish metabolites with healthy potential, such as anticancer or antioxidant activities, is increasingly reported. In this study, the Mediterranean “fried egg jellyfish” Cotylorhiza tuberculata (Macri, 1778) has been targeted in the search forputative valuable bioactive compounds. A medusa extract was obtained, fractionated, characterized by HPLC, GC-MS and SDS-PAGE and assayed for its biological activity on breast cancer cells (MCF-7) and human epidermal keratinocytes (HEKa). The composition of the jellyfish extract included photosynthetic pigments, valuable ω-3 and ω-6 fatty acids, and polypeptides derived either from jellyfish tissues and their algal symbionts. Extract fractions showed antioxidant activity and the ability to affect cell viability and intercellular communication mediated by gap junctions (GJIC) differentially in MCF-7and HEKa cells. A significantly higher cytotoxicity and GJIC enhancement in MCF-7 compared to HEKa cells was recorded. A putative action mechanism for the anticancer bioactivity through the modulation of GJIC has been hypothesized and its nutraceutical and pharmaceutical potential was discussed.
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Affiliation(s)
- Antonella Leone
- Institute of Sciences of Food Production, National Research Council, Unit of Lecce (CNR, ISPA), Via Prov.le Lecce-Monteroni, Lecce 73100, Italy; E-Mails: (R.M.L.); (M.D.)
- CoNISMa, National Interuniversity Consortium on Marine Sciences, Local Unit of Lecce, Via Prov.le Lecce-Monteroni, Lecce 73100, Italy; E-Mail:
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +39-0832-422-615; Fax: +39-0832-422-620
| | - Raffaella Marina Lecci
- Institute of Sciences of Food Production, National Research Council, Unit of Lecce (CNR, ISPA), Via Prov.le Lecce-Monteroni, Lecce 73100, Italy; E-Mails: (R.M.L.); (M.D.)
- CoNISMa, National Interuniversity Consortium on Marine Sciences, Local Unit of Lecce, Via Prov.le Lecce-Monteroni, Lecce 73100, Italy; E-Mail:
| | - Miriana Durante
- Institute of Sciences of Food Production, National Research Council, Unit of Lecce (CNR, ISPA), Via Prov.le Lecce-Monteroni, Lecce 73100, Italy; E-Mails: (R.M.L.); (M.D.)
| | - Stefano Piraino
- CoNISMa, National Interuniversity Consortium on Marine Sciences, Local Unit of Lecce, Via Prov.le Lecce-Monteroni, Lecce 73100, Italy; E-Mail:
- University of Salento, Via Prov.le Lecce-Monteroni, Lecce 73100, Italy
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Longo C, Leo L, Leone A. Carotenoids, fatty acid composition and heat stability of supercritical carbon dioxide-extracted-oleoresins. Int J Mol Sci 2012; 13:4233-4254. [PMID: 22605975 PMCID: PMC3344211 DOI: 10.3390/ijms13044233] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 03/13/2012] [Accepted: 03/19/2012] [Indexed: 11/17/2022] Open
Abstract
The risk of chronic diseases has been shown to be inversely related to tomato intake and the lycopene levels in serum and tissue. Cis-isomers represent approximately 50%-80% of serum lycopene, while dietary lycopene maintains the isomeric ratio present in the plant sources with about 95% of all-trans-lycopene. Supercritical CO(2) extraction (S-CO(2)) has been extensively developed to extract lycopene from tomato and tomato processing wastes, for food or pharmaceutical industries, also by using additional plant sources as co-matrices. We compared two S-CO(2)-extracted oleoresins (from tomato and tomato/hazelnut matrices), which showed an oil-solid bi-phasic appearance, a higher cis-lycopene content, and enhanced antioxidant ability compared with the traditional solvent extracts. Heat-treating, in the range of 60-100 °C, led to changes in the lycopene isomeric composition and to enhanced antioxidant activity in both types of oleoresins. The greater stability has been related to peculiar lycopene isomer composition and to the lipid environment. The results indicate these oleoresins are a good source of potentially healthful lycopene.
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Affiliation(s)
- Cristiano Longo
- Unit of Lecce (ISPA-CNR), Institute of Sciences of Food Production, National Research Council, Via Prov.le Lecce-Monteroni, 73100 Lecce, Italy; E-Mails: (C.L.); (L.L.)
| | - Lucia Leo
- Unit of Lecce (ISPA-CNR), Institute of Sciences of Food Production, National Research Council, Via Prov.le Lecce-Monteroni, 73100 Lecce, Italy; E-Mails: (C.L.); (L.L.)
| | - Antonella Leone
- Unit of Lecce (ISPA-CNR), Institute of Sciences of Food Production, National Research Council, Via Prov.le Lecce-Monteroni, 73100 Lecce, Italy; E-Mails: (C.L.); (L.L.)
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Piccoli C, D'Aprile A, Scrima R, Ambrosi L, Zefferino R, Capitanio N. Subcytotoxic mercury chloride inhibits gap junction intercellular communication by a redox- and phosphorylation-mediated mechanism. Free Radic Biol Med 2012; 52:916-27. [PMID: 22240155 DOI: 10.1016/j.freeradbiomed.2011.12.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 12/09/2011] [Accepted: 12/20/2011] [Indexed: 11/26/2022]
Abstract
Gap junctions play a central role in coordinating intercellular signal-transduction pathways to control tissue homeostasis. Deregulation of gap junctional intercellular communication is a common phenotype of cancer cells and supports its involvement in the carcinogenesis process. Many carcinogens, like environmental heavy-metal chemical pollutants, are known to activate various signal transduction mechanisms and modulate GJIC. They act as tumor promoters on preexisting "initiated" cells, rather than as genotoxic initiators, albeit their mode of action is often unknown. In this study we investigated the effect of Hg(II) (HgCl(2)) on GJIC in cultured human keratinocytes. It is shown that subcytotoxic concentrations of HgCl(2) as low as 10 nM cause inhibition of the GJIC, assessed by dye transfer assay, despite enhanced expression of connexins. In addition, HgCl(2)-treated keratinocytes exhibited a decrease of free thiols and accumulation of mitochondria-derived reactive oxygen species, albeit no effect on the respiratory chain activity was observed. Treatment of HgCl(2)-exposed keratinocytes with the PKC inhibitor calphostin C and with all-trans retinoic acid resulted in rescue of the mitochondrial ROS overproduction and full recovery of the GJIC. Similar results were obtained with the PKA activator db-cAMP. Overall, the presented results support a cross-talk between the altered intracellular redox tone and PKA- and PKC-mediated signaling in HgCl(2)-challenged keratinocytes. These events, although not cytotoxic, lead to inhibition of GJIC and possibly to carcinogenic priming.
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Affiliation(s)
- Claudia Piccoli
- Department of Biomedical Sciences, University of Foggia, Foggia, Italy
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