OBJECTIVETo investigate the promotive effect of transplantation of bone morphogenetic protein-2 (BMP-2) gene transfected bone mesenchymal stem cells (BMSCs) compounded with injectable bone tissue engineering scaffold material Pluronic F-127 on bone regeneration in rabbit mandibular distraction osteogenesis(DO).

METHODSForty-eight New Zealand's white rabbits were randomized into four groups with twelve in each. All the objects were prepared into DO surgical model. On the 2nd day of consolidation, group A, B, C and D were injected with the same amount of 200 microL of the compound of BMP-2 gene transfected BMSCs with Pluronic F-127, the solution with BMP-2 gene transfected BMSCs, the solution of BMSCs and physiological saline at distraction zone, respectively. Two halves of the objects of all groups were sacrificed at the end of 2nd and 6th week consolidation, respectively. And the specimens of right mandible were prepared for radiological, histomorphological and immunohistochemical examinations to evaluate bone regeneration.

RESULTSBoth radiological and immunohistochemical images were analyzed and processed with professional software. At the end of 2nd and 6th week consolidation, the bone mineral density and the expression of BMP-2 protein in distraction area of group A were significantly higher than those of B, C, D group (P<0.01). Group B was significantly higher than that in group C and D (P<0.01). There was no significant difference between group C and D (P>0.05). And the regeneration quality of distraction zone in group A and B were better than those in group C and D, just as that of group A better than group B. Conclusion The transplantation of BMP-2 gene transfected BMSCs compound with Pluronic F-127 could effectively promote bone regeneration in rabbit mandibular DO.

Animals ; Bone Density ; Bone Morphogenetic Proteins ; Bone Regeneration ; Mandible ; Mesenchymal Stromal Cells ; Osteogenesis ; Osteogenesis, Distraction ; Poloxamer ; Rabbits ; Tissue Engineering ; Tissue Scaffolds ; Transfection

OBJECTIVE To investigate the effect of arctiin （ARC）relieving lipopolysaccharide （LPS）induced inflammatory injury of human nasopharyngeal epithelial cells NP- 69. METHODS The effects of 24 h treatment of 0.000 1，0.001，0.01，0.1， 1.0，10 μmol/L ARC on the proliferation of NP-69 were determined by MTS method. After 0.01，0.1，and 1.0 μmol/L ARC was applied to NP- 69 for 24 h and NP- 69 was pre-treated with 0.01，0.1 and 1.0 μmol/L ARC for 24 h，and then stimulated with 1.0 μg/mL LPS for 24 h，scratch tests were used to detect cell migration in both experiments. LPS stimulated NP- 69 to establish an inflammation injury model. The levels of nitric oxide （NO），tumor necrosis factor α（TNF-α）interleukin-6（IL-6），and IL- 1β in cell supernatants were detected ，and mRNA and protein expression of zonula oecludens protein 1（ZO-1），β-defensin 3（BD3）， Janus kinase 1 （JAK1），signal transducer and activator of transcription 3 （STAT3） in cell supernatant were also detected. RESULTS Compared with normal group ，0.000 1，0.001，0.01，0.1，1.0，10 μmol/L ARC had no effect on the proliferation of NP-69 after 24 h treatment （P＞0.05）. ARC （0.1，1.0 μmol/L）could significantly promote the rate of cell migration （P＜0.05）. For the inflammatory injure of NP- 69 cells stimulated by LPS ，ARC（1.0 μmol/L）could significantly reduce the release of NO ， TNF-α and IL-6（P＜0.05），significantly increased mRNA and protein expression of ZO- 1 and BD 3 but decreased mRNA and protein expression of STAT 3（P＜0.01 or P＜0.05）. CONCLUSIONS ARC has the effect of reducing the inflammatory injury of NP-69 cells induced by LPS ，promoting the physical and immune defense ability of the nasal mucosa epithelial barrierunder inflammatory environment. The mechanism of action may be related to inhibiting IL- 6/JAK1/STAT3 signaling pathway.

Potassium 2-(1-hydroxypentyl)-benzoate (d,l-PHPB), a new drug candidate for ischemic stroke at the phase II clinic trial, has been shown to protect neurons by inhibiting oxidative injury and reducing neuron apoptosis in previous studies. But the mechanisms of d,l-PHPB remain to be studied. In this study, a neuron-astrocytes co-culture system was used to elucidate the roles of astrocytes in neuroprotection of d,l-PHPB under oxygen-glucose deprivation/reoxygenation (OGD/R) condition. Our data showed that d,l-PHPB reduced neuronal apoptosis in mono-culture system and this effect was enhanced in neuron-astrocyte co-culture system under the OGD/R condition. Meanwhile, d,l-PHPB obviously increased the levels of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), which were mainly secreted from astrocytes, in the co-culture system after OGD/R. The PI3K/AKT and ERK signaling pathways as well as the p-TRKA/B receptors were involved in the process. In addition, the levels of TNF-and IL-1secreted from astrocytes after OGD/R were markedly reduced after d,l-PHPB treatment, which was mainly due to the suppression of phosphorylated p38. In conclusion, the present study demonstrates that the neuroprotective effects of d,l-PHPB were improved by astrocytes, mainly mediated by increasing the release of BDNF/NGF and attenuating inflammatory cytokines.