ABSTRACT
BACKGROUND: Mesenchymal stem cells (MSCs), with low immunogenicity, can regulate cellular immunity and mitigate graft rejection, which has a good prospect in tissue engineering. However, it is rarely present in bone marrow. OBJECTIVE: To explore an isolation and culture method of the rabbit bone marrow-derived MSCs, to observe the biological characteristics and differentiation potential of bone marrow-derived MSCs.METHODS: MSCs were isolated from rabbit tibia bone marrow by combination of gradient centrifugation and different adherent method, then proliferation in vitro. Morphology was examined by phase contrast microscopy, and the growth curve of cultured MSCs was drawn via MTT results. MSCs were treated with osteogenetic inductor (L-DMEM/F12, 10% fetal bovine serum, 0.1 μmol/L dexamethasone, 200 μmol/L vitamin C, 10 mmol/L β-phosphoglycerol), adipose inductor (L-DMEM/F12, 10% FBS, 1 μmol/L dexamethasone, 200 μmol/L antifani, 0.5 mmol/L IBMX, 10 μg/mL insulin), and chondrocytes inductor (L-DMEM/F12, 10% FBS, 10 μg/L TGF-β1, 0.1 μmol/L dexamethasone, 50 μmol/L vitamin C, 6.25 mg/L insulin) to differentiated into osteoblast, dipocytes and chondrocytes. And the differentiated cells were identified by alkaline phosphatase staining, oil red O staining, and toluidine blue staining, respectively.RESULTS AND CONCLUSION: Bone marrow-derived MSCs can be isolated and cultured by the combination of gradient centrifugation and different adherent method in vitro, which have the better potentiality of proliferation and multi-directional differentiation. Mostly of the primary and passaged cells were spindle-shaped. After osteogenetic induction, cells were positive to alkaline phosphatase staining. Oil red O staining showed that red lipid droplet existed in adipose cells, and toluidine blue staining showed that toluidine blue was positive after chondrocytes induction.
ABSTRACT
Objective To investigate the effeets of insulin on the apoptosis of vascular endothelial cells cuinduced by burn$eruln in order to explore its possible mechamsm.Method Cultured human ECV304 cells were randomly divided into 33x)ups:control group,the ECV304 cells hured by 15%(V/V)rat normal,qertlm(t=6);bum semm group,the ECV3()4 cells simulated by 15%(V/V)self-made burn semm collected from rats with 30%TBSA full-thickness burns on the,back(n=6);and burn Serum+insulin group.the ECV304 cells cultared by insulin(10-7mol/L)and 15%(V/V) seIf-made rat bum serum(n=6).The transferase mediated nick end labeling(TUNEL) method was employed to measure the apoptosis of endothelial cells at 6 hours after stimulation.Meanwhile.immanohistochemical technique and Western blotting were used to determine the protein expressions of bcl-2 and eNOS.Data are expressed ills mean ±SEM.Statistical comparison was made using oneway analysis of vtriance.Significance was accepted at P<0.05.Results Compswith the control group,bum$erunl induced the apoptusis(18.5±3.1%)and down-regalated bcl·2(O.36±0.12)and p-eNOS(O.55±0.28)protein expressions of HUVECs(P<0.01).Burn 9AJ'unl+insulin significantly decreased the apoptosis(9.6 4-2.8%)and up-regulated bcl-2(0.944-0.25)and p-eNOS(0.89±0.16)protein expressions ofHU-VECs in comparison with the bum serllm group(P<0.01).eNOS showed no significant differences in three groups.Conclusions Insulin could markedly inhibit the apoptosis and up-regalate bcl-2 protein expression of HUVECs induced by bum serum,and its mec,harfism might involve the protein expression ofphosphorylated eNOS.