Role of NF-κB activation in lipopolysaccharide inhibitting albumin expression in rat hepatocytes

Objective To investigate whether the reduction of albumin expression induced by LPS was mediated by activating nuclear factor kappaB(NF-κB) in cultured rat hepatocytes.Methods Primary rat hepatocytes were divided into five groups treated with normal saline,LPS(1 ng/ml),LPS(0.01 μg/ml),LPS(0.1 μg/ml),or LPS(1 μg/ml) for 24 h.The albumin level in the supernatant and NF-κB activity in hepatocytes were measured.Hepatocytes were pretreated for 30 min with SN50(a highly selected inhibitor of NJ-κB)at different concentrations(10 μg/ml,30 μg/ml and 50 μg/ml).After 24 hours of treatment with different comentration of LPS,the culture medium was tested for albumin level.Meanwhile,NF-κB activity in hepatocytes was assayed.Results LPS dramatically decreased albumin expression and enhanced NF-κB activity in rat hepatocytes,especially in the 1 μg/ml LPS group.This reduction in albumin expression induced by LPS was completely blocked by SN50 at different concentrations.Conclusion The results suggest that LPS inhibits albumin expression by activating NF-κB.NF-κB is the most important reason that causes albumin expression decrease.