Toxicology 241 (2007) 75–83 Available online at www.sciencedirect.com Assessment of the astrogliotic responses of three human astrocytoma cell lines to ethanol, trimethyltin chloride and acrylamide Lindsay J. Holden, Michael D. Coleman ∗ School of Life and Health Sciences, Aston University, Birmingham B4 7ET, UK Received 5 July 2007; received in revised form 1 August 2007; accepted 10 August 2007 Available online 15 August 2007 Dedicated to the memory of M.J. Winn, PhD. Abstract The astrogliotic responses of the CCF-STTG1, U251-MG, and U373-MG human astrocytoma lines were determined after exposure to ethanol, trimethyltin chloride (TMTC), and acrylamide over 4, 16, and 24 h. Basal glial fibrillary acidic protein (GFAP) expression in the U-251MG and U373-MG cells was 10-fold greater than the CCF-STGG1 line. Ethanol treatment over 24 h, but not at 4 and 16h, resulted in significant increases in GFAP in all three glioma lines at sub-cytotoxic levels; the GFAP responses in the CCF- STTG1 line were the most sensitive, as concentrations of 0.1 and 1 mM led to increases in GFAP expression compared with control of 56.8 ± 15.7 and 58.9 ± 11.5%, respectively (P < 0.05). Treatment with TMTC (1 M) over 4 h showed elevated GFAP expression in the U251-MG cell line to 28.0 ± 15.7% above control levels (P < 0.01), but not in the other U373-MG or CCF-STTG1 cells. At 4 h, MTT turnover was markedly increased compared with control, particularly in the U373-MG line at concentrations as low as 1 M (17.1 ± 2.3%; P < 0.01). TMTC exposure over 16 and 24 h resulted in reduction in GFAP expression in all three lines at concentrations; at 24 h incubation, the reduction was >50% (P < 0.01). There were no changes in GFAP expression or MTT turnover in response to acrylamide except at the highest concentration ranges of 10–100 mM. This study underlines the significance of period of exposure, as well as toxin concentration in astrocytoma cellular response to toxic pressure. © 2007 Elsevier Ireland Ltd. All rights reserved. Keywords: Gliomas; Ethanol; Trimethyltin chloride; Astrocytoma; GFAP; Toxicity; MTT 1. Introduction Astrocytes have an integral role in the maintenance of homeostasis within the CNS, although they are also intimately associated with both neuroprotection and neu- rodegradation when they are activated in response to trauma and disease states (Rohl et al., 2007). Astrocytes ∗ Corresponding author. Tel.: +44 121 204 3916; fax: +44 121 359 0733. E-mail address: m.d.coleman@aston.ac.uk (M.D. Coleman). also release cytokines and other soluble factors, which may induce adverse responses in surrounding neuronal tissue (Harry et al., 1998; Viviani et al., 2000), although conversely, neuronal tolerance of many toxins is substan- tially increased by the proximity of astrocytes (Yu and Zuo, 1997; Zhou et al., 2004; Woehrling et al., in press). Astrocytic activation, or astrogliosis, is triggered by several processes and leads to the upregulation of the structural protein glial fibrillary acidic protein (GFAP; Eng et al., 2000). Specifically, GFAP is a sensitive marker for detecting astrogliosis-mediated effects, which would not necessarily be observed by conventional cytotoxi- 0300-483X/$ – see front matter © 2007 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.tox.2007.08.083