Effect and mechanisms of FR167653, a dual inhibitor of TNF-alpha and IL-1, on BCG plus LPS induced-liver injury.

OBJECTIVE

To investigate the effect of FR167653, a dual inhibitor of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1), on Bacillus Calmétte-Guérin (BCG) plus lipopolysaccharide (LPS) induced-liver injury and its mechanisms.

MATERIAL AND METHODS

Mouse liver injury was established by tail vein injection of 2.5 mg BCG, and 10 d later with 10 microg LPS. The alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were assayed by spectrophotometry. Liver samples were stained with hematoxylin and eosin. Rat hepatocytes (HCs) and Kupffer cells (KCs) were isolated by collagenase IV and pronase perfusion, and purified by density gradient separation. TNF-alpha and IL-1 concentrations were measured with ELISA. TNF-alpha and IL-1 mRNA in KCs was analyzed with RT-PCR.

RESULTS

FR167653 significantly decreased the elevated transaminase (ALT, AST) activity in serum of liver injured mice. Meanwhile, the degree of inflammatory cell infiltration and liver cell necrosis was also ameliorated. TNF-alpha and IL-1 production by KCs stimulated with LPS was significantly inhibited by FR167653. RT-PCR analysis demonstrated that FR167653 also reduced the augmented expression of TNF-alpha and IL-1 mRNA in KCs. However, FR167653 up to 10 micromol/L did not have a toxic effect on KC viability. In addition, FR167653 alleviated the HC injury induced by LPS pre-treated Kupffer cell-conditioned medium (KCCM). Addition of anti-IL-1 and anti-TNF-alpha MAbs significantly decreased the ALT level released from HCs incubated with LPS or FR167653 pre-treated KCCM.

CONCLUSIONS

TNF-alpha and IL-1 released from activated KCs were involved in BCG plus LPS induced liver injury. FR167653 significantly attenuated hepatocyte injury via inhibition of TNF-alpha and IL-1 released from activated KCs.