Liver fibrosis in different treatment groups as assessed by Sirius-red staining.

The canines were administered repeated carbon tetrachloride (CCl4) injections to induce liver fibrosis and treated with bone marrow-derived mesenchymal stem cells (BMSCs) via the peripheral vein (Vein group) or hepatic artery (Artery group). (a) In the Control group, the fibrosis level increased over time from 11.3 ± 3.9% (0W) to 12.4 ± 4.3% (4W), 12.7 ± 2.6% (8W), and 12.9 ± 2.8% (12W). (b) In the Vein group, the fibrosis level decreased from 9.2 ± 2.7% (0W) to 7.2± 3.5% (4W), 6.4 ± 2.7% (8W), and 6.9 ± 2.7% (12W). (c) In the Artery group, the fibrosis level decreased significantly from 11.0 ± 2.5% (0W) to 7.2 ± 1.2% (4W; p < 0.05), 6.8 ± 1.3% (8W; p < 0.05), and 6.9 ± 1.0% (12W; p < 0.05). 4W, 8W, and 12W denote weeks post-BMSC administration.