Regulation of pro-inflammatory and anti-inflammatory cytokine responses by Kupffer cells in endotoxin-enhanced reperfusion injury after total hepatic ischemia

The effects of Kupffer cells on cytokine responses in endotoxin-enhanced reperfusion injury after total hepatic ischemia were investigated in this study. Male rats pre-treated with either normal saline solution (NS group) or gadolinium chloride (GdCl3) to inhibit Kupffer cell function (GC group) were subjected to 60 min of hepatic ischemia. These animals received either normal saline solution or sublethal doses of endotoxin (1 mg/kg) at reperfusion. In the NS group, endotoxin administration induced an enhanced tumor necrosis factor-alpha (TNF-alpha) and interleukin-10 production 1 h after reperfusion with a subsequent peak of macrophage inflammatory protein-2 (MIP-2) levels, which resulted in a 7-day survival rate of 30%. Despite endotoxin administration, GdCl3 pretreatment significantly suppressed TNF-a and increased interleukin-10 production 1 h after reperfusion, which led to a decline in MIP-2 production and amelioration of functional and structural liver damage with a 7-day survival rate of 80%. Augmented pro-inflammatory and anti-inflammatory cytokine responses by Kupffer cells were associated with endotoxin-enhanced reperfusion injury after hepatic ischemia. Kupffer cell blockade has a potential to attenuate the insult via modulation of cytokine responses.