Pvl. Rao et al., FRESH-WATER CYANOBACTERIUM MICROCYSTIS-AERUGINOSA (UTEX-2385) INDUCEDDNA-DAMAGE IN-VIVO AND IN-VITRO, Environmental toxicology and pharmacology, 5(1), 1998, pp. 1-6
Microcystins are a family of potent hepatotoxins and liver tumor promo
ters produced by several genera of cyanobacteria including Microcystis
, Nodularia, Anabena, Nostoc, etc. They are chemically very stable and
represent a public health threat when they occur in water used for hu
man consumption. We investigated the DNA damage effects of M. aerugino
sa UTEX 2385 in mouse liver in vivo and also in mammalian cells in vit
ro. The DNA damage effect is compared with purified toxin microcystin-
LR (MCLR) in non-hepatic cells viz. baby hamster kidney cells (BHK-21)
and mouse embryo fibroblasts primary cells (MEF). Cell-free extracts
of UTEX 2385 induced significant DNA fragmentation at 0.5, 1 and 2 LD5
0 (32.7, 65.4 and 130.8 mg/kg, respectively) and it was also time depe
ndent. M. aeruginosa UTEX 2385 and MCLR induced significant DNA fragme
ntation in BHK-21 and MEF cells at 100 and 1.0 mu g/ml concentration.
Electrophoretic analysis revealed necrotic DNA damage by UTEX 2385 in
vivo. Both the toxins caused smear in agarose gel electrophoresis indi
cating the necrotic DNA damage in MEF cells, whereas, multiple DNA fra
gments in BHK-21 cells. The DNA damage effect of the toxin is supporte
d by data on hepatotoxicity in vivo and cytotoxicity in vitro. (C) 199
8 Elsevier Science B.V.