Expression of discoidin domain receptors (DDR2) in alcoholic liver fibrosis in rats.

BACKGROUND AND AIMS

We undertook this study to evaluate the expression of discoidin domain receptor 2 (DDR2) and its relationship with alcoholic liver fibrosis.

METHODS

Liver fibrosis was induced by intragastric administration of alcohol in 30 rats. Pathological changes and ultrastructure of the liver were studied. The expression of DDR2 mRNA and protein was detected by RT-PCR and Western blot, respectively, at weeks 12, 16 and 20 during the alcohol administration.

RESULTS

In the control group (con) (n = 10), DDR2 mRNA expression and DDR2 protein were 1.02 ± 0.13 (con ratio x10⁻³) and 0.32 ± 0.03, respectively. In the study groups there was a progressive increase in DDR2 mRNA expression from weeks 12, 16 and 20 (3.64 ± 1.69, 8.34 ± 2.39, 15.73 ± 4.57 con ratio x10⁻³, p <0.05). There was also a progressive increase in DDR2 protein from weeks 12-20 (0.48 ± 0.05, 0.74 ± 0.06 and 0.99 ± 0.05, p <0.05). The mean DDR2 mRNA and protein in the three study groups was higher than in the control group (p <0.01). The expressions of DDR2 mRNA and protein were positively correlated with collagen type I, III and IV in liver tissues as well as with the serum biomarkers of liver fibrosis, collagen type III, hyaluronic acid, collagen type IV and laminin (p <0.01).

CONCLUSIONS

The expression of DDR2 in this alcohol-induced liver fibrosis rat model is enhanced. The expression of DDR2 is closely associated with collagens in the fibrotic liver tissues.