title: Application of cellular biosensors for detection of atypical toxic bioactivity in microcystin-containing cyanobacterial extracts.
abstract: Despite the focus of most ecotoxicological studies on cyanobacteria on a select group of cyanotoxins, especially microcystins, a growing body of evidence points to the involvement of other cyanobacterial metabolites in deleterious health effects. In the present study, original, self-developed reporter gene-based cellular biosensors, detecting activation of the main human xenobiotic stress response pathways, PXR and NFkappaB, were applied to detect novel potentially toxic bioactivities in extracts from freshwater microcystin-producing cyanobacterial blooms. Crude and purified extracts from cyanobacteria containing varying levels of microcystins, and standard microcystin-LR were tested. Two cellular biosensor types applied in this study, called NHRTOX (detecting PXR activation) and OXIBIOS (detecting NFkappaB activation), successfully detected potentially toxic or immunomodulating bioactivities in cyanobacterial extracts. The level of biosensor activation was comparable to control cognate environmental toxins. Despite the fact that extracts were derived from microcystin-producing cyanobacterial blooms and contained active microcystins, biosensor-detected bioactivities were shown to be unrelated to microcystin levels. Experimental results suggest the involvement of environmental toxins (causing a response in NHRTOX) and lipopolysaccharides (LPS) or other cell wall components (causing a response in OXIBIOS) in the potentially harmful bioactivity of investigated extracts. These results demonstrate the need for further identification of cyanobacterial metabolites other than commonly studied cyanotoxins as sources of health risk, show the usefulness of cellular biosensors for this purpose and suggest a novel, more holistic approach to environmental monitoring.
authors.affiliation: European Regional Centre for Ecohydrology of the Polish Academy of Sciences, 3 Tylna, 90-364 Łódź, Poland; Department of Applied Ecology, Faculty of Biology and Environmental Protection, University of Łódź, 12/16 Banacha, 90-237 Łódź, Poland. Electronic address: j.mankiewicz@erce.unesco.lodz.pl.
authors.forename: Joanna
authors.initials: J
authors.lastname: Mankiewicz-Boczek
authors.affiliation: Laboratory of Transcriptional Regulation, Institute of Medical Biology of the Polish Academy of Sciences, 106 Lodowa, 93-232 Łódź, Poland.
authors.forename: Iwona
authors.initials: I
authors.lastname: Karwaciak
authors.affiliation: Laboratory of Transcriptional Regulation, Institute of Medical Biology of the Polish Academy of Sciences, 106 Lodowa, 93-232 Łódź, Poland.
authors.forename: Marcin
authors.initials: M
authors.lastname: Ratajewski
authors.affiliation: European Regional Centre for Ecohydrology of the Polish Academy of Sciences, 3 Tylna, 90-364 Łódź, Poland.
authors.forename: Ilona
authors.initials: I
authors.lastname: Gągała
authors.affiliation: Department of Applied Ecology, Faculty of Biology and Environmental Protection, University of Łódź, 12/16 Banacha, 90-237 Łódź, Poland.
authors.forename: Tomasz
authors.initials: T
authors.lastname: Jurczak
authors.affiliation: European Regional Centre for Ecohydrology of the Polish Academy of Sciences, 3 Tylna, 90-364 Łódź, Poland.
authors.forename: Maciej
authors.initials: M
authors.lastname: Zalewski
authors.affiliation: Laboratory of Transcriptional Regulation, Institute of Medical Biology of the Polish Academy of Sciences, 106 Lodowa, 93-232 Łódź, Poland; Department of Molecular Biophysics, Faculty of Biology and Environmental Protection, University of Łódź, 12/16 Banacha, 90-237 Łódź, Poland. Electronic address: lpulaski@uni.lodz.pl.
authors.forename: Łukasz
authors.initials: Ł
authors.lastname: Pułaski
mesh_terms: D000818:Animals; D015374:Biosensing Techniques; D002460:Cell Line; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D000458:Cyanobacteria / Q000737:chemistry*; D054750:Ecotoxicology / Q000379:methods*; D004784:Environmental Monitoring / Q000379:methods* / Q000592:standards; D056945:Hep G2 Cells; D006801:Humans; D008387:Marine Toxins; D052998:Microcystins / Q000378:metabolism / Q000633:toxicity*; D011817:Rabbits; D014874:Water Pollutants, Chemical / Q000633:toxicity
chemical_list: D008387:Marine Toxins; D052998:Microcystins; D014874:Water Pollutants, Chemical; C078588:microcystin; C057862:cyanoginosin LR
keywords: Biological activity; Cellular biosensors; Cyanobacterial extract; Immunotoxicity; Microcystins; Reporter genes