Attached
INTRODUCTION AND OBJECTIVES: Freshwater
resources are now threatened by the presence and increase of toxic cyanobacterial blooms all over the world.
This is typically a direct result of anthropogenic pollution
of water bodies, such as partially treated nutrient-rich
effluents and the leaching of fertilizers and animal
wastes. Approximately 75% of water samples containing cyanobacteria consists cyanobacterial secondary
metabolites which can produce toxic effects to livestock,
. wildlife and human. There is a wide spectrum of cyanotoxins, predominantly causing neurotoxic, hepatotoxic
and dermatotoxic effects on contaminated individuals.
In diverse aquatic systems, cyclic peptide toxins microcystins (MCs) and nodularin are the most abundant
and most noxious cyanotoxins present causing highest
impact on hepatocytes. Though these toxins are reputed as potent hepatotoxins, recent evidence suggests
that these peptides could cause kidney injuries. Present
study was carried out to evaluate cytotoxic effects of
some selected MCs (MC-LR, MC-RR, MC-LF and MCLW) and Nodularin on human embryonic kidney cells
(HEK-293) and
METHOD: Human kidney adenocarcinoma cells (ACHN).
HEK-293 and ACHN cells were treated with different
concentrations of MC-LR, MC-RR, MC-LF, MC-LW and
Nodularin (1.0-200 pM) for 24 h and cytotoxicity was
evaluated by Sulphorhodamine B (SRB) assay.
RESULTS: A significant cytotoxicity was induced in both
types of cells by the toxins tested. All the toxins had a
significantly higher cytotoxicity on normal kidney cells than on the kidney adenocarcinoma cells. Furthermore,
MC-LR had the lowest IC50 values (16.57±0.035 for
HEK-293 and 62.36±0.037 for ACHN cells) while MC-LW
had the highest IC50 values (1158.16±9.025 for HEK-293
and 1589.78±3.206 for ACHN cells).
CONCLUSION: Overall findings of the present study
demonstrate that cyanotoxins could cause cytotoxic
effects on kidney cells. MC-LR was the most toxic while
MC-LW was least toxic cyanotoxin on both cell types
tested. MC-RR, MC-LF and Nodularin had moderate cytotoxicity on human renal cells.
Key words: Microcystins, Nodularin, ACHN cells, HEK293 cells, cytotoxicity
This work was financially supported by National Research Council of Sri Lanka Grant 11-034.
1 Department of Zoology, Faculty of Applied sciences,
University of Sri Jayewardenepura, Gangodawila, Nugegoda, Sri Lanka.2 Institute of Biochemistry, Molecular
Biology and Biotechnology, University of Colombo, 90,
Cumaratunga Munidasa Mawatha, Colombo 03, Sri
Lanka.
