Effect of endotoxin pretreatment on hepatic stellate cell response to ethanol and acetaldehyde

Background and Aim: The role of endotoxin in alcohol-induced liver damage is well recognized. How pre-exposure to endotoxin might affect alcohol injury is not known. We herein studied the effect of endotoxin pretreatment on hepatic stellate cell (HSC) response to ethanol and acetaldehyde. Methods: Rat HSC (CFSC-2G) were exposed to media supplemented with 1 mug/mL lipopolysaccharide (LPS). This was followed by a 24 h exposure to media containing LPS plus 50 mmol/L ethanol or 175 mumol/L acetaldehyde. Lipid peroxidation, collagen, and tumor necrosis factor (TNF)-alpha interleukin (IL)-1beta, IL-6 and transforming growth factor (TGF)-beta(1) secretion were determined at the end of both periods of exposure. Results: Lipopolysaccharide pretreatment did not modify lipid peroxidation induced by ethanol or acetaldehyde alone. Glutathione (GSH) content decreased to 4.2 +/- 0.5 and 16.3 +/- 0.8 nmol protein after exposure to ethanol or acetaldehyde alone, and decreased further with LPS pretreatment (2.4 +/- 0.2 and 2.7 +/- 0.3 nmol/mg protein, respectively). Oxidized GSH (GSSG) content increased in ethanol and acetaldehyde LPS-pretreated cells only. Collagen secretion increased to 988 +/- 82 and 1169 +/- 91 mug/10(6) cells after exposure to acetaldehyde or LPS alone. Lipopolysaccharide pretreatment enhanced collagen secretion significantly in both ethanol- and acetaldehyde-treated cells (969 +/- 56 and 1360 +/- 72 mug/10(6) cells, respectively). Interleukin-6 production increased to 288 +/- 48, 1195 +/- 86 and 247 +/- 35 pg/mL per 10(6) cells after ethanol, acetaldehyde and LPS exposure, and increased further with LPS pretreatment in ethanol-exposed cells (680 +/- 23 pg/mL 10(6) cells). Conclusion: Lipopolysaccharide pretreatment of HSC adds to the damage produced by ethanol and acetaldehyde by diminishing GSH content and increasing GSSG content, collagen and IL-6 secretion. (C) 2001 Blackwell Science Asia Pry Ltd.