Apoptosis and Bcl-2 expression in the livers of patients with steatohepatitis.
OBJECTIVE
Apoptosis may play a role in the pathogenesis of alcoholic (ASH) and non-alcoholic steatohepatitis (NASH). In this study, we investigated the modulation of apoptosis-related liver proteins in steatohepatitis.


METHODS
Hepatocyte apoptosis was evaluated by the TUNEL assay in liver tissue of 12 patients with NASH, 12 with ASH and in histologically normal controls. In addition, caspase-3 processing was evaluated by immunoblot analysis. Expression of death receptors, Bcl-2 family members, and NF-kappaB inhibitor (IkappaB) were determined by western blot. Liver biopsies were also graded for inflammation and fibrosis.


RESULTS
Apoptotic hepatocytes were markedly increased in NASH (P<0.05) and ASH (P<0.001) as compared to controls. Active caspase-3 was also elevated in steatohepatitis (P<0.01), coinciding with upregulation of pro-apoptotic Bax (P<0.001). Further, production of tumour necrosis factor-receptor 1 was increased up to 4-fold (P<0.05). Degradation of IkappaB increased >70% in steatohepatitis (P<0.001). Notably, Bcl-2 was also strongly expressed (>100-fold; P<0.001). These data were significantly correlated with relative degrees of portal and lobular inflammation.


CONCLUSIONS
The results show that liver injury in NASH and ASH is associated with apoptosis and NF-kappaB activation. Anti-apoptotic Bcl-2 is strongly expressed, probably reflecting an adaptive response to obesity or alcohol-related stress.
Ramalho
Rita M
RM
Centro de Patogénese Molecular, Faculty of Pharmacy, University of Lisbon and Department of Gastroenterology, Hospital of Santa Maria, Lisbon, Portugal.
Cortez-Pinto
Helena
H
Castro
Rui E
RE
Solá
Susana
S
Costa
Adília
A
Moura
Miguel C
MC
Camilo
Maria E
ME
Rodrigues
Cecília M P
CM
D000328:Adult; D017209:Apoptosis; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D005234:Fatty Liver / Q000378:metabolism / Q000473:pathology*; D005235:Fatty Liver, Alcoholic / Q000378:metabolism / Q000473:pathology; D005260:Female; D022781:Hepatocytes / Q000473:pathology*; D006801:Humans; D020672:I-kappa B Proteins / Q000378:metabolism; D007124:Immunoenzyme Techniques; D020287:In Situ Nick-End Labeling; D008099:Liver / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D016328:NF-kappa B / Q000037:antagonists & inhibitors; D011446:Prospective Studies; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D047888:Receptors, Tumor Necrosis Factor, Type I / Q000378:metabolism
D020672:I-kappa B Proteins; D016328:NF-kappa B; D019253:Proto-Oncogene Proteins c-bcl-2; D047888:Receptors, Tumor Necrosis Factor, Type I; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases