Effect of Vascular Cell Adhesion Molecule -1 Overexpression on Adipogenic Differentiation of Murine Mesenchymal Stem Cells and Its Mechanism / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the effect of vascular cell adhesion molecule-1 (VCAM-1) gene overexpression on adipogenic differentiation of mouse mesenchymal stem cells(MSC) and explore its molecular mechanism.</p><p><b>METHODS</b>VCAM-1 overexpression MSC (MIGR1-VCAM-1/MSC) and the empty plasmid transfection MSC (MIGR1/MSC) were induced to adipogenic differentiation, oil-red-O staining and real-time PCR were used to detect the adipogenic differentiation ability and the mRNA expression level of key transcription factors C/EBP α and PPAR γ. The activation of P38, ERK and JNK pathways were analyzed by Western blot. Furthermore, the specific chemical inhibitors of MAPK pathway (SB203580, PD98059 and JNK inhibitor II) were added to the induced culture system and the alteration of the MSC adipogenic differentiation ability were evaluated.</p><p><b>RESULTS</b>no matter in self or induced differentiation groups, the lipid droplets in MIGR1-VCAM-1/MSC became larger, the amount of adipocyte increased than that in MIGR1/MSC (P<0.01), the mRNA expression level of C/EBPα and PPARγ were upregulated, and JNK pathway were down-regulated while the P38 and ERK pathway were significantly up-regulated. The inhibition of JNK pathway of MIGR1-VCAM-1/MSC could lead to increased mRNA expression level of C/EBP α and PPAR γ, the amount of adipocytes increased (P<0.01), however, the inhibition of the P38 and ERK pathway of MIGR1-VCAM-1/MSC could lead to decreased mRNA expression level of C/EBP α and PPAR γ, and the lipid droplets and the number of adipocytes became smaller and less.</p><p><b>CONCLUSION</b>The overexpression of VCAM-1 may promote MSC to differentiate into adipocytes through inhibiting JNK signaling pathway, activating P38 and ERK pathways.</p>

Effect of Knockdown of Vascular Cell Adhesion Molecule-1 on the Immunologic Regulation Capacity of Murine Mesenchymal Stem Cells / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To establish the stably lower expression of vascular cell adhesion molecule-1 (VCAM-1) in MSC cell line (C3H10T1/2) by siRNA technology, and explore the effect of knockdown of VCAM-1 on the immunologic regulation capacity of murine MSC.</p><p><b>METHODS</b>The mouse GV118-VCAM-1-RNAi retrovirus vector was constructed by gene recombination technology. The recombinant plasmid was identified by restriction analysis and sequencing, and then the recombinant plasmid GV118-VCAM-1-RNAi was transfected into 293 cells by Lipofectamine, and the supernatant was collected to transfect C3H10T1/2. Moreover, the VCAM-1 lower expression on MSC was evaluated by flow cytometry and fluorescent microscopy. The knockdown VCAM-1 MSC was sorted by flow cytometry. Furthermore, the inhibitory effect of the knockdown VCAM-1 MSC on lymphocyte proliferation was tested by lymphoblast transformation assay (LTT) and mixed lymphocyte reaction assay(MLR).</p><p><b>RESULTS</b>The recombinant retroviral vector of knockdown VCAM-1 (GV118-VCAM-1-RNAi) was successfully constructed and transfected into mouse MSC cell line C3H10T1/2. The knockdown VCAM-1/MSC was obtained by flow cytometric sorting. The LTT and MLR assay showed that the immunosuppressive effect of MSC lower-expressing VCAM-1 dramatically decreased (P<0.05).</p><p><b>CONCLUSION</b>Knockdown VCAM-1 in MSC can significantly down-regulate the inhibitory capability of MSC on the proliferation of T-cells. The data of this study laid an experimental foundation for studying effect of VCAM-1 transfecting into MSC on immune function.</p>