Antileukoproteinase protects against hepatic inflammation, but not apoptosis in the response of D‐galactosamine‐sensitized mice to lipopolysaccharide

Abstract

Background and purpose: There is major evidence for the strong bi-directional interrelation of parenchymal cell apoptosis and leukocyte accumulation and inflammation in acute liver injury. Therefore, the aim of this in vivo study was to investigate the anti-apoptotic and anti-inflammatory potential of antileukoproteinase (ALP) in a murine model of acute liver failure. Experimental approach: C57BL/6J mice were given galactosamine (D-GalN) and E. coli lipopolysaccharide (LPS) followed by administration of saline or ALP. Besides survival rate, hepatic tissue damage and inflammatory response were analyzed by intravital fluorescence microscopy 6 hours after treatment. In addition, immunohistochemical analysis of NFkB-p65 and hepatocellular apoptosis, plasma levels of AST/ALT, TNF-a and IL-10 were determined. Key results: Administration of D-GalN/LPS provoked hepatic damage, including marked leukocyte recruitment and microvascular perfusion failure, as well as hepatocellular apoptosis and enzyme release. NFkB-p65 became increasingly detectable in hepatocellular nuclei, accompanied by a rise of TNF-a and IL-10 plasma levels. ALP markedly reduced intrahepatic leukocyte accumulation, nuclear translocation of NFkB and plasma levels of TNF-a and IL-10. Moreover, liver enzyme levels indicated the absence of necrotic parenchymal cell death. In contrast, ALP failed to block both apoptosis and caspase-3 levels and the mortality rate of ALP-treated animals was comparable to that of saline-treated mice. Conclusions and implications: ALP could effectively prevent D-GalN/LPS-associated intrahepatic inflammatory responses by inhibition of NFkB activity, but not apoptosis-driven mortality. Thus, a protease-inactivating approach such as application of ALP seems to be inadequate in damaged liver where apoptosis represents the predominant mode of cell death.

Oxidative stress-associated rise of hepatic protein glycation increases inflammatory liver injury in uncoupling protein-2 deficient mice

“…31,32 and were studied 6 h later. Time-matched sham-treated animals with application of equivalent volumes of 0.9% saline were performed and designated as sham (n ¼ 14).…”

Matrix Metalloproteinases as Drug Targets in Infections Caused by Gram-Negative Bacteria and in Septic Shock

“…Another frequently used approach is the simultaneous injection of animals with LPS and D-galactosamine, a hepatotoxic drug (30). This treatment increases the sensitivity of mice to the lethal effects of LPS.…”

Role of the perforin/granzyme cell death pathway ind-Gal/LPS-induced inflammatory liver injury

“…For hematoxylin and eosin staining and immunohistochemical analysis of cleaved caspase-3-and TUNEL-positive hepatocytes, we used standard protocols as previously published by our group (5,17,30).…”

“…For induction of acute liver failure, mice (n ϭ 26) were injected with D-Gal (720 mg/kg body wt ip; Sigma-Aldrich, Taufkirchen, Germany) and LPS (10 g/kg body wt ip; Escherichia coli serotype 0128:B12, Sigma-Aldrich) (5,17). Additional series of time-matched sham-treated animals with application of equivalent volumes of 0.9% saline were performed and designated as controls (n ϭ 26).…”

“…Although mechanisms of LPS-induced liver injury are not completely understood, it is well known that hepatocytes are the major target cells in acute liver failure and that inflammatory cells, such as macrophages and neutrophils, dominate the manifestation of injury (4,5,27). These initial innate responses have been discovered to be dependent on intact adaptive immune cells, which are shown to temper the ongoing early response to infection and to function as negative regulators (14).…”