In vivo assessment of the hepatotoxicity of a new Nostoc isolate from the Nile River: Nostoc sp. strain NRI

Abu-Serie, M.M. and Nasser, N. and Abd El-Wahab, A. and El-Shehawy, R. and Pienaar, H. and Baddour, N. and Amer, R. (2018) In vivo assessment of the hepatotoxicity of a new Nostoc isolate from the Nile River: Nostoc sp. strain NRI. Toxicon, 143. pp. 81-89. ISSN 00410101

Full text not available from this repository.
Official URL: http://dx.doi.org/10.1016/j.toxicon.2018.01.010

Abstract

Nostoc sp. is one of the most widely distributed cyanobacterial genera that produce potentially protein phosphatase (PP) inhibitor; microcystins (MCs). MCs have posed a worldwide concern due to predominant hepatotoxicity to human health. We have previously isolated a Nostoc strain (NR1) from the Nile River (the main water supply in Egypt) and this strain exerted production of rare and highly toxic MC; demethylated microcystin-LR. There is no data concerning risk factors of liver diseases for human and animal exposure to NR1-contaminated drinking water yet. It is thus important to evaluate acute (LD50 dose), subacute (0.01% and 10% of LD50 dose) and subchronic (0.01% and 10% of LD50 dose) hepatotoxicity's NR1 extract using experimental mice. Mice groups, who orally received 0.01% LD50, represented a permissible concentration of the World Health Organization (WHO) for MC in drinking water. Several parameters were detected, including hepatotoxicity (i.e. PP activity, liver function, oxidative stress markers and DNA fragmentation), pro-inflammatory cytokine (TNF-alpha) and liver histopathology. Our results demonstrated LD50 of NR1 extract was at 15,350 mg/kg body weight and caused hepatotoxicity that attributed to PP inhibition and a significant increase of hepatic damage biomarkers with lipid accumulation. Moreover, NR1 extract induced hepatic oxidative damage that may have led to DNA fragmentation and production of TNF-alpha. As demonstrated from the histopathological study, NR1 extract caused a severe collapse of cytoskeleton with subsequent focal degeneration of hepatocytes, necroinflammation and steatosis. The grade of hepatotoxicity in subacute (10% of LD50) group was higher than that in the subchronic (10% of LD50 and 0.01% of LD50, WHOch, respectively) groups. No significant hepatotoxicity was detectable for subacute (0.01% of LD50, WHOac) group. NR1 is therefore considered as one of the harmful and life-threatening cyanobacteria for Egyptian people being exposed to dose above WHO guideline. Thus, biological indicators and thresholds for water treatment are extremely needed.

Item Type: Article
Subjects: Q Science > QR Microbiology
Depositing User: José Ángel Gómez Martín
Date Deposited: 23 May 2018 11:25
Last Modified: 23 May 2018 11:25
URI: http://eprints.imdea-agua.org:13000/id/eprint/901

Actions (login required)

View Item View Item