Microbial metabolite of dimethylarsinic acid is highly toxic and genotoxic

Kuroda, K; Yoshida, K; Yoshimura, M; Endo, Y; Wanibuchi, H; Fukushima, S; Endo, G

HERO ID

627176

Reference Type

Journal Article

Year

2004

Language

English

PMID

15276414

HERO ID 627176
In Press No
Year 2004
Title Microbial metabolite of dimethylarsinic acid is highly toxic and genotoxic
Authors Kuroda, K; Yoshida, K; Yoshimura, M; Endo, Y; Wanibuchi, H; Fukushima, S; Endo, G
Journal Toxicology and Applied Pharmacology
Volume 198
Issue 3
Page Numbers 345-353
Abstract Dimethylarsinic acid [DMA, (CH3)2AsO(OH)] causes cancer in the urinary bladder of rats. However, its mechanism of cancer or the ultimate carcinogenic form is not yet known. Rats administered dimethylarsinic acid excrete three unknown arsenic compounds (termed M-1, M-2, and M-3) in urine or feces, and these compounds are presumed to be produced by intestinal bacteria. Escherichia coli A3-6 isolated from a rat yielded two unknown arsenic compounds (M-2 and M-3) from dimethylarsinic acid and M-1 from trimethylarsine oxide (TMAO) in the presence of cysteine (Cys). Contents of M-2 and M-3 varied with cysteine concentration. The cytotoxicity and genotoxicity of the bacteria-free solution of dimethylarsinic acid or trimethylarsine oxide metabolized by E. coli A3-6 were studied using V79 cells. Dimethylarsinic acid (1 mM) metabolized by E. coli A3-6 in the presence of cysteine (1 mM) was highly cytotoxic (50% survival reduction concentration; 2.1 AM As) in V79 cells, and the toxic substance appeared to be M-2. The metabolite solution (at 2.5–10 AM total As) induced c-mitosis and tetraploids, and caused mitotic arrest, since it increased mitotic cells at the cytotoxic dose. The metabolite solution also significantly increased sister chromatid exchange (SCE) and chromosomal aberrations, most of which were chromatid gaps and chromatid breaks. A3-6 converted 96.1% of trimethylarsine oxide to M-1 in the presence of cysteine. This metabolite solution did not exhibit cytotoxicity or genotoxicity. The reported M-2 concentration in urine of rats administered levels of DMA via drinking water known to cause bladder tumors was sufficient to exhibit cytotoxic and genotoxic effects in urinary bladder. Thus, we hypothesize that intestinal bacteria play an important role in carcinogenicity of dimethylarsinic acid.
Doi 10.1016/j.taap.2003.10.014
Pmid 15276414
Wosid WOS:000223146600012
Is Certified Translation No
Dupe Override No
Comments |WOS:000223146600012
Is Public Yes
Language Text English
Keyword dimethylarsinic acid; Escherichia coli; SCE; chromosomal aberration; tetraploid; mitotic arrest; C-mitosis
Is Qa No