Recombinant bovine pancreatic trypsin inhibitor protects the liver from carbon tetrachloride-induced chronic injury in rats

Figures & data

Figure 1. Effect of rBPTI on body weight and relative liver weight in rats. rBPTI: ecombinant bovine pancreatic trypsin inhibitor; pHGF: hepatocyte growth-promoting factors. The rats were treated with 40% (v/v) CCl₄ dissolved in corn oil subcutaneously at a dose of 2 ml/kg body weight twice a week for 12 weeks. In the 8th week, the rats were treated with rBPTI (80 MU/kg), BPTI (80 MU/kg) and pHGF (100 mg/kg) intraperitoneally every day for the next 4 weeks. In saline and saline/CCl₄ groups, the rats received the saline (5 ml/kg) only. During the administration of rBPTI, BPTI, pHGF and saline, the rats still received the same administration of 40% (v/v) CCl₄ for the next 4 weeks. Data are shown as mean ± SD (n = 10). ##p < 0.01 compared with saline group (group 1). *p < 0.05 compared with saline/CCl₄ group (group 2).

Figure 2. Effect of rBPTI on activities of serum ALT and AST and albumin in rats. ALT, alanine aminotransferase; AST, aspartate aminotransferase; see Figure 1 for the treatment. Data are shown as mean ± SD (n = 10). ##p < 0.01 compared with saline group (group 1). *p < 0.05 compared with saline/CCl₄ group (group 2).

Figure 3. Effect of rBPTI on liver Hyp contents in rats. Hyp, hydroxyproline; see Figure 1 for the treatment. Data are shown as mean ± SD (n = 10). ##p < 0.01 compared with saline group (group 1). *p < 0.05 compared with saline/CCl₄ group (group 2).

Figure 4. Effect of rBPTI on liver TBARS and SOD activity in rats. TBARS, thiobarbituric acid reactive substance; SOD, superoxide dismutase; see Figure 1 for the treatment. Data are shown as mean ± SD (n = 10). ##p < 0.01 compared with saline group (group 1). *p < 0.05 compared with saline/CCl₄ group (group 2).

Table 1. Effects of rBPTI on cytokines levels in rats treated with carbon tetrachloride.

Group	IL-1β	TGF-β	TNF-α
Saline	1.19 ± 0.17	1.18 ± 0.22	1.42 ± 0.45
Saline/CCl4	3.87 ± 0.43^†	3.09 ± 0.68^†	2.15 ± 0.89
pHGF/CCl4	3.02 ± 0.69*	2.39 ± 0.47*	1.85 ± 0.36
BPTI/CCl4	3.12 ± 0.80*	2.32 ± 0.69*	1.89 ± 0.57
rBPTI/CCl4	3.19 ± 0.76*	2.34 ± 0.61*	1.72 ± 0.78

rBPTI, recombinant bovine pancreatic trypsin inhibitor; pHGF, hepatocyte growth-promoting factors; IL-1β, interleukin 1β; TGF-β, transforming growth factor β; TNF-α, tumor necrosis factor α; Data are shown as mean ± SD (n = 10).

*p < 0.05 compared with saline/CCl₄ group (group 2).

^†p < 0.01 compared with saline group (group 1).

Figure 5. rBPTI reduces carbon tetrachloride-induced liver damage in rats. Paraffin-embedded liver tissue sections were stained with H&E for light microscopic assessment of liver damage (200 × magnification). Images shown are representative of 10 rats in each group.

Table 2. rBPTI protects carbon tetrachloride-induced chronic liver damage.

Group	Liver fibrosis average					Necrosis average					Fatty degeneration average					Inflammatory cell average
	0	1	2	3		0	1	2	3		0	1	2	3		0	1	2	3
Saline	10	0	0	0	0	10	0	0	0	0	10	0	0	0	0	10	0	0	0	0
Saline/CCl4	0	0	3	7	2.7	0	7	3	0	1.3	0	0	2	8	2.8	0	5	5	0	1.5
pHGF/CCl4	4	6	0	0	0.6*	9	1	1	0	0.3*	0	6	4	0	1.4*	3	7	0	0	0.7*
BPTI/CCl4	4	5	1	0	0.5*	10	0	0	0	0*	0	5	5	0	1.5*	2	8	0	0	0.8*
rBPTI/CCl4	3	6	1	0	0.6*	10	0	0	0	0*	0	6	4	0	1.4*	2	8	0	0	0.8*

rBPTI, recombinant bovine pancreatic trypsin inhibitor; pHGF, hepatocyte growth-promoting factors; see Figure 1 for the treatments. Normal (0), light (1), moderate (2) or severe (3). Liver fibrosis: Grade 0, normal liver; grade 1, increased collagen and (or) formation of incomplete septa; grade 2, formation of complete septa; grade 3, formation of thick septa. Liver cell necrosis: Grade 0, no liver cell necrosis; grade 1, less than 25%; grade 2, 25–50%; grade 3, more than 50%. Fatty degeneration: Grade 0, no fatty degeneration; grade 1, less than 25%; grade 2, 25–50%; grade 3, more than 50%. Inflammatory cell infiltrate: Grade 0, no inflammatory cells in hepatic lobule and portal area, and a small amount of inflammatory cells in sinus hepaticus; grade 1, a small amount of inflammatory cells in hepatic lobule and portal area; grade 2, more amounts of inflammatory cells in hepatic lobule and portal area; grade 3, widespread infiltration of inflammatory cells in almost all hepatic lobule and portal area.

*p < 0.05 compared with saline/CCl₄ group (group 2).