Résumé
Objective: To investigate the induction of tanshinone [1 A (Tan fl A) on the differentiation of human placenta-derived mesenchymal stem cells (hPDMSCs) into cardiomyocytes, and to provide an experimental basis for Tan IT A as a cardiomyocytc differentiation inducer. McthodS; The hPDMSCs were treated with different concentrations of Tan Fl A (0.1.0.2.0.4.0.6.0.8.1.0. 2.0. 4.0. 6.0. 8.0. and 10. 0 mg • L ). and the nontoxic dose of Tan II A <0. 1 mg • L ) was scrccncd by MTT assay for experiment. The hPDMSCs were divided into control group. 5-aza induction (10 pmol • L ) group, and Tan Fl A induction (0. 1 mg • L ) group. After culture for 20 d. the expressions of o-sarcomeric acun (o-SCA) in the cells in various groups were detected with lmmunohistochcmastry; the positive expression rates of cardiac troponin 1 (cTnl) in the cells in various groups were detected with immunofluorescence, and the differentation rates of cardiomyocytes were calculated. The expression levels of GATA-binding protein 4 (GATA4). atnal natriuretic factor (ANF). cTnl. glycogen synthase kmase-30 (GSK-30 ) and 0-catemn in the cells were detected with Western blotting method. Results: The biological characteristics of hPDMSCs accorded with the mesenchymal stem cells. The MTT results showed that when the concentration of TanFl A was more than 0. 1 mg • L . the cell survival rates were decreased with the increase of concentrations the cells in control group showed a rapid growth trend before 12 d. and the proliferation activities of the cells began to decrease on the 12th day. Compared with control group, the cell activities in 5-aza induction group and TanFl A induction group were significantly decreased < P<0. 05). The immunohistochcmistry staining results showed that the cells in control group didn' t express a-SCA. and the cells in 5-aza induction group and TanFl A induction group expressed o-SCA. cspcaally in Tan Fl A induction group. Compared with control group, the expression levels of GAT A4 ( i - 2.937. P <0.05,4.769, P ,| , <0. 05) . ANF ( t -3.728. P <0.05 j r.-5.912, P ., ,<0.05). cTnl
Résumé
Abstract Objective: The aim of the study was to evaluate the effects of the capping materials mineral trioxide aggregate (MTA), calcium hydroxide (CH) and BiodentineTM (BD) on stem cells from human exfoliated deciduous teeth (SHED) in vitro. Material and Methods: SHED were cultured for 1 - 7 days in medium conditioned by incubation with MTA, BD or CH (1 mg/mL), and tested for viability (MTT assay) and proliferation (SRB assay). Also, the migration of serum-starved SHED towards conditioned media was assayed in companion plates, with 8 μm-pore-sized membranes, for 24 h. Gene expression of dentin matrix protein-1 (DMP-1) was evaluated by reverse-transcription polymerase chain reaction. Regular culture medium with 10% FBS (without conditioning) and culture medium supplemented with 20% FBS were used as controls. Results: MTA, CH and BD conditioned media maintained cell viability and allowed continuous SHED proliferation, with CH conditioned medium causing the highest positive effect on proliferation at the end of the treatment period (compared with BD and MTA) (p<0.05). In contrast, we observed increased SHED migration towards BD and MTA conditioned media (compared with CH) (p<0.05). A greater amount of DMP-1 gene was expressed in MTA group compared with the other groups from day 7 up to day 21. Conclusion: Our results show that the three capping materials are biocompatible, maintain viability and stimulate proliferation, migration and differentiation in a key dental stem cell population.