7,12-Dimethylbenz(a)anthracene-induced genotoxicity on bone marrow cells from mice phenotypically selected for low acute inflammatory response.

Autor: Katz IS; Immunogenetics Laboratory, Butantan Institute, São Paulo, Brazil., Albuquerque LL; Immunogenetics Laboratory, Butantan Institute, São Paulo, Brazil., Suppa AP; Immunogenetics Laboratory, Butantan Institute, São Paulo, Brazil., da Silva GB; Laboratory of Experimental Hematology, Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil., Jensen JR; Immunogenetics Laboratory, Butantan Institute, São Paulo, Brazil., Borrego A; Immunogenetics Laboratory, Butantan Institute, São Paulo, Brazil., Massa S; Immunogenetics Laboratory, Butantan Institute, São Paulo, Brazil., Starobinas N; Immunogenetics Laboratory, Butantan Institute, São Paulo, Brazil., Cabrera WH; Immunogenetics Laboratory, Butantan Institute, São Paulo, Brazil., De Franco M; Immunogenetics Laboratory, Butantan Institute, São Paulo, Brazil., Borelli P; Laboratory of Experimental Hematology, Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil., Ibañez OM; Immunogenetics Laboratory, Butantan Institute, São Paulo, Brazil., Ribeiro OG; Immunogenetics Laboratory, Butantan Institute, São Paulo, Brazil. Electronic address: orlando.ribeiro@butantan.gov.br.
Jazyk: angličtina
Zdroj: DNA repair [DNA Repair (Amst)] 2016 Jan; Vol. 37, pp. 43-52. Date of Electronic Publication: 2015 Dec 02.
DOI: 10.1016/j.dnarep.2015.11.006
Abstrakt: Exposure to polycyclic aromatic hydrocarbon (PAH) environmental contaminants has been associated with the development of mutations and cancer. 7,12-Dimethylbenz(a)anthracene ( DMBA), a genotoxic agent, reacts with DNA directly, inducing p53-dependent cytotoxicity resulting in cell death by apoptosis or giving rise to cancer. DMBA metabolism largely depends on activation of the aryl hydrocarbon receptor (AhR). Mice phenotypically selected for high (AIRmax) or low (AIRmin) acute inflammatory response present a complete segregation of Ahr alleles endowed with low (Ahr(d)) or high (Ahr(b1)) affinity to PAHs, respectively. To evaluate the role of AhR genetic polymorphism on the bone marrow susceptibility to DMBA, AIRmax and AIRmin mice were treated with a single intraperitoneal injection of DMBA (50mg/kg b.w.) in olive oil. Bone marrow cells (BMCs) were phenotyped by both flow cytometry and cytoslide preparations. Despite a significant decrease in total cell count in BM from AIRmin mice, there was an increase of blast cells and immature neutrophils at 1 and 50 days after DMBA treatment, probably due to a cell-cycle blockade at the G1/S transition leading to immature stage cell production. A panel of proteins related to cell cycle regulation was evaluated in immature BM cells (Lin(-)) by Western Blot, and DNA damage and repair were measured using an alkaline version of the Comet assay. In Lin(-) cells isolated from AIRmin mice, high levels were found in both p53 and p21 protein contents in contrast with the low levels of CDK4 and Ciclin D1. Evaluation of DNA repair in DMBA-treated BMCs, indicated long-lasting genotoxicity and cytotoxicity in BMC from AIRmin mice and a blockade of cell cycle progression. On the other hand, AIRmax mice have a high capacity of DNA damage repair and protection. These mechanisms can be associated with the differential susceptibility to the toxic and carcinogenic effects of DMBA observed in these mice.
(Copyright © 2015 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
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