Bone marrow mesenchymal stem cells can inhibit hepatic stellate cells proliferation by influencing PI3K/Akt singal pathway

ObjectiveTo investigate the mechanism of bone marrow mesenchymal stem cells (MSCs) regulating the proliferation of hepatic stellate cells (HSCs) under non-contact co-culture in vitro.Methods Rat MSCs/Rats HSCs were seeded in proportion (2 × 104/2 × 104 cells/well) in the Transwell co-culture plate as the experimental group to establish the upper and lower double-cell co-culture system.HSCs were separately cultured (2 × 104 cells/well) in a well as control group. LY294002 as the inhibitor of PI3K/Akt signal pathway was added to co-culture group and control group respectively (20 μmol/ml), which served as the positive control group. Cell cycle was determined at different co-culture time points (24, 48,72 h) by using flow cytometry. The p-Akt and Akt protein expression in HSCs was detected by using Western blotting. Results HSCs co-cultured with MSCs at different time points (72, 48, 24 h) significantly inhibited HSCs proliferation as compared with the mono-culture groups, and the tendency become obvious with the passage of time ( 11.24 ± 0. 34 ＜ 15.73 ± 0. 76 ＜ 19. 14 ± 0. 91 ＜ 23. 16 ± 1.80, P ＜ 0. 05 ). The inhibitory effect was become larger after adding the LY294002 into the co-culture groups than the co-culture groups ( 8.2 ± 0. 8 ＜ 11.7 ± 1.6, P ＜ 0. 05 ). After HSCs co-cultured with MSCs for 24 h, the expression of p-Akt protein was reduced, and significantly reduced in the co-culture group added with the LY294002. No significant difference was found in Akt protein in any group. Conclusion MSCs can significantly inhibit HSCs proliferation through influencing the PI3K/Akt signal pathway, and the p-Akt is the key point. Key words: Hepatic stellate cells; Bone marrow mesenchymal stem cells; PI3K/Akt signal pathway; Co-culture