Extent of liver resection modulates the activation of transcription factors and the production of cytokines involved in liver regeneration

Figure 1 Liver-body-weight-ratio of control animals, sham-operated and 70% resected animals given in g per 100 g body weight. Controls had a LBW-r of 4.04% ± 0.15%.

Figure 2 Serum levels of liver related enzymes, each given in U/L and mg/dL for bilirubin, respectively. A: ALT, base level in serum was 36.2 ± 5.2 U/mL; B: AST in controls was 84.0 ± 31.1 U/mL in serum; C: LDH, basal release of LDH into serum was 2416 ± 1088 U/mL; D: Bilirubin, with a baseline serum level of 0.3 ± 0.3 mg/dL.

Figure 3 ELISA results of nucleic protein extracts. A: Active NF-κB. Baseline activation was 111 pg/μg total protein; B: Phosphorylated STAT3 (tyrosine 705) in total cellular protein. Activation in control animals was 4.5 U/mL. Protein was isolated from regenerating rat liver after 70% or 90% resection, respectively, at different time points after surgery. All data are normalized to an internal standard and are shown as mean values of four separate experiments. Significance is given versus control group.

Figure 4 mRNA was isolated from regenerating liver tissue of rats at different time points after 70% or 90% resection, respectively. A: TNF-α (< 50 copies/100 000 copies β-actin); B: IL-6 (< 15 copies/100 000 copies β-actin); C: HGF (50 000 copies/100 000 copies β-actin); D: TGF-β (< 2500 copies/100 000 copies β-actin); E: TGF-β (< 5500 copies/100 000 copies β-actin). Measurement of cytokine and growth-factor expression was performed by quantitative real-time (rt) PCR. Copy numbers of each gene were calculated from ct values. Data shown are the mean of four separate experiments with standard error of mean. All statistical significances were calculated against control animals. Baseline expression of each gene is given in parentheses.

Figure 5 Representative images of TUNEL staining in liver tissue from the following groups. A: Positive control; B: Negative control; C: 70% resection, 24 h after surgery; D: 90% resection, 24 h after surgery; E: 70% resection 7 d after surgery; F: 90% resection, 7 d after surgery.

Figure 6 Results of TUNEL staining from paraffin embedded tissue sections. Paraffin embedded tissue slides from regenerating rat liver were dewaxed, washed and stained using the TUNEL method. The slides were covered in anti-fade medium with DAPI and analysed with a fluorescence microscope. False positive results were ruled out by comparison of the images with DAPI counterstaining (not shown). The TUNEL index is the number of TUNEL-positive cells divided by the total cell number. Cells were counted in ten fields of vision per section. Numbers shown are mean of four separate experiments in each group. TUNEL index for control animals (no resection) was approximately 0.12%.