ABSTRACT
Objective To study the expression of vascular endothelial growth factor(VEGF)in hepatic tissue of acute liver failure(ALF)rats after transplantation of microencapsulated hepatocytes.Methods The ALF model of rats was induced by D-galactosamine(D-Gal)1400 mg/kg.Then the ALF rats were divided into three groups 18 h after injection of D-Gal:ALF model group,free hepatocyte transplantation group,and microencapsulated hepatocyte transplantation group,50 rats in each group,respectively.Each group was divided into 7 subgroups,and the rats were sacrificed at 24,36,48,72,120,168 and 240 h respectively after injection of D-Gal.The expression of proliferating cell nuclear antigen(PCNA) and VEGF in liver tissue of ALF rats was detected by immunohistochemistry method.VEGF mRNA in liver tissue was detected by semi-quantitative reverse transcription polymerase chain reaction(RT-PCR).Comparison among groups was done by one way ANOVA.Results Compared with ALF model group,the expression of PCNA protein and in free hepatocyet transplantation group in microencapsulated hepatocyte transplantation group began to increase obviously at 36 h after injection of D-Gal(F=26.26,P<0.05).Compare to that of ALF model and free hepatocyte transplantation group,the expression of VEGF protein in microencapsulated hepatocyte transplantation group increased significantly at 36 h after injection of D-Gal(F=25.44,P<0.05),which decreased slower and was still higher at 240 h after injection of D-Gal(F=220.25,P<0.05).Compared with ALF model group,the expression of VEGF mRNA in free hepatocyte transplantation group increased obviously at 24 h(48.0±1.9 vs 56.7±9.1;F=3.54,P<0.05).And that in microencapsulated hepatocyte transplantation group was higher than free hepatocyte transplantation group at 48 h(100.7±1.9 vs 94.5±1.4;F=47.82,P<0.05),which was still significantly higher than free hepatocyte transplantation group at 240 h after injection of D-Gal(F=21.70,P<0.05). Conclusion Transplantation of microencapsulated hepatocytes could upregulate the expression of VEGF in liver tissues and promote the regeneration of hepatocytes in ALF rats.
ABSTRACT
Objective To investigate Smac/DIABLO and cytochrome c(cyt-c)mRNA levels in liver tissue of rats with acute hepatic failure treated by microencapsulated hepatocyte.Methods Acute hepatic failure were induced by intraperitoneal injection of D-galactosamine in rats.and the rats were treated with microencapsulated hepatocytes,free hepatocytes and physical saline(contr01),respectively.Smac/DIABLO and cyt-c mRNA in liver tissue was detected by RT-PCR and the mRNA expression levels among three groups were compared.Results Smac/DIABLO and cyt-c mRNA levels in liver tissues of rats with acute hepatic failure were higher than those of normal rata(F=4.345,14.821,47.565,42.178 and 62.961,P<0.05).The peak values of Smac/DIABLO and cyt-C mRNA expressions in free hepatocytes and control groups were at 48 h.while that in microencapsulated hepatoeytes group was at 24 h.Conclusion Smac/DIABLO and cyt-c mRNA expression is an indicator of apoptosis of hepatocytes.
ABSTRACT
Objective To investigate liver regeneration after transplantation of microencapsulated hepatocytes in rats with acute liver failure (ALF). Methods ALF rat model was established by intraperitoneal injection of D-galactosamine (D-GalN). After 18 h, rats were randomized into control group ( Ⅰ ), free hepatoeyte transplantation group ( Ⅱ ) and the microencapsulated hepatecyte transplantation group (Ⅲ). Six rats for each group were randomly selected and sacrificed at 6, 12, 24, 36, 48, 72, 120, 168 and 240 h after ALF induced and blood samples from inferior vena cava were collected. Liver functions were tested in blood samples, and the expression of proliferating cell nuclear antigen (PCNA) was detected by immunohistochemistry. Results Ten-day survival rates of 3 groups were 26.7% (4/15), 40.0% (6/15) and 73. 3% (11/15), respectively (x2 = 9. 349,P = 0. 009). Survival rate of group Ⅲ was significantly higher than that of group Ⅰ and Ⅱ. Levels of ALT and AST in each group increased significantly at 6 h after ALF induced, and peaked between 48 ～ 72 h. Levels of ALT and AST in group Ⅱ and Ⅲ declined from 36 h, which was more significant in group Ⅲ. Tbil levels in group Ⅰ gradually increased after ALF induced and peaked at 72 h. Tbil in group Ⅱ and Ⅲ declined from 48 h, which was more markedly in group Ⅲ. In normal rats, the expression of PCNA protein was almost negative, but it was strongly expressed in ALF rats and peaked at 48 h. The number of positive cells in group Ⅲ was higher than that in group Ⅰ and Ⅱ, and the differences were of statistical signifieance. Conclusion The transplantation of microencapsulated hepatocytes can promote the regeneration of liver, and it can improve the liver function and prognosis in rats with ALF.