Zoledronate inhibits the differentiation potential of adipose-derived stem cells into osteoblasts in repairing jaw necrosis

ObjectiveTo explore the inhibitory effects of zoledronate (ZOL) on adipose-derived stem cells (ADSCs) into osteoblasts for repairing jaw necrosis.MethodsADSCs were induced to differentiate into osteoblasts. The differentiation characteristics of osteoblasts was observed under inverted microscope by alizarin red staining. The transwell assay was performed to evaluate the migration of ADSCs co-cultured with osteoblasts and divided into ZOL group treated with ZOL and N-ZOL group without ZOL treatment. The differentiation and proliferation characteristics of ADSCs differentiated osteoblasts were observed respectively. The expression of CTSK (Cathepsin K) and FGFR3 (Fibroblast growth factor receptor 3) in osteoblasts were analyzed by immunofluorescence and western blot.ResultsThe differentiation degree and proliferation of ADSCs to osteoblasts in N-ZOL group were both higher than those in ZOL group. The migratory cell number in ADSCs differentiation in ZOL group was higher than that of N-ZOL group. The protein expression of CTSK and FGFR3 in ADSCs differentiated to osteoblasts in ZOL group was higher than that in N-ZOL group.ConclusionThe differentiation of ADSCs into osteoblasts is significantly inhibited by ZOL. Due to this reason, it may be difficult to achieve good results by ZOL induced ADSCs into osteoblasts in repairing jaw necrosis.     

Crosstalk Between Mucosal Inflammation and Bone Metabolism in Chronic Rhinosinusitis

Chronic rhinosinusitis (CRS) is a multifactorial and highly heterogeneous upper airway disease that affects approximately 12% of the general population. There is increasing evidence supporting the impact of osteitis on the pathophysiology of CRS. Osteitis is frequently observed in patients with CRS, and is associated with severe sinonasal inflammation and recalcitrant cases. The overlying inflammatory sinonasal mucosa plays a critical role in the initiation of osteitis; however, the underlying molecular mechanisms and functional significance remain unclear. Increasingly many studies have suggested that immune cells play a crucial role in the bone remodeling process in CRS. The purpose of this review is to summarize the current state of knowledge regarding the specific role of sinonasal inflammation in bone remodeling in CRS patients.     

IL-17A stimulates the expression of inflammatory cytokines via celecoxib-blocked prostaglandin in MC3T3-E1 cells

Objective

The prostaglandins (PGs) released from osteoblasts can alter the process of bone remodelling. Recently, we showed that compressive force induced the expression of pro-inflammatory cytokine interleukin (IL)-17s and their receptors in osteoblastic MC3T3-E1 cells and that IL-17A was expressed most highly. Consequently, in the current study we examined the effect of IL-17A and/or celecoxib on PGE₂ production and the expression of cyclooxygenases (COXs) and inflammatory cytokines in MC3T3-E1 cells. We also examined the effects of PGE₂ and cyclohexamide on the expression of inflammatory cytokines.

Methods

Cells were cultured with or without IL-17A (0.1, 1.0, or 10 ng/ml) in the presence or absence of 10 μM celecoxib, a specific inhibitor of COX-2, for up to 72 h. Cells were pretreated with or without 10 μg/ml cycloheximide, protein synthesis inhibitor, for 30 min, and then cultured with 10 ng/ml IL-17A for 24 h. Cells were also cultured with or without 1.5 ng/ml PGE₂ for 24 h. PGE₂ production was determined by ELISA. The expression of COX-1, COX-2, IL-1α, IL-6, IL-8, IL-11, and TNF-α mRNAs and proteins was determined by real-time PCR and ELISA, respectively.

Results

The expression of COX-2, IL-1α, IL-6, IL-8, IL-11, and TNF-α, as well as PGE₂ production increased in the presence of IL-17A, whereas COX-1 expression did not change. Celecoxib blocked the stimulatory effect of IL-17A on the expression of COX-2, IL-1α, IL-6, IL-8, and IL-11 as well as PGE₂ production, whereas it did not block TNF-α expression. Cycloheximide pretreatment suppressed the expression of IL-17-induced inflammatory cytokines. The expression of IL-1α, IL-6, IL-8, and IL-11 increased by the addition of PGE₂, whereas TNF-α expression was not affected.

Conclusion

These results suggest that IL-17A stimulates the expression of bone resorption-related inflammatory cytokines through an autocrine mechanism involving celecoxib-blocked PGs, mainly PGE₂, in osteoblasts.     

成骨样细胞受张力作用后PGE_2含量及IGF-I表达变化

目的 观察机械张力对成骨样细胞合成PGE2和IGF-I基因表达的影响。方法 通过Flexercell细胞拉伸力学装置对人成骨样细胞Saos-2进行6％、12％和24％的拉伸应变加载实验。用放免法和Northern斑点杂交技术检测细胞受力后的PGE2水平和IGF-ImRNA表达变化。结果 三种拉伸率均能显著增加Saos-2细胞PGE2的含量。虽然6％和12％的应力作用能明显增加IGF-I的表达,但24％的力值刺激几乎对IGF-I表达无影响。结论 张应力可以促进人成骨样细胞PGE2的合成,但只有恰当大小的力值才能增加其IGF-I基因的表达。     

Paxillin phosphorylation and integrin expression in osteoblasts infected by Porphyromonas gingivalis

OBJECTIVE: We investigated early biological events initiated by Porphyromonas gingivalis infection of human osteoblasts, focusing on tyrosine-phosphorylation and the expression of key components in focal adhesion and cell signalling. DESIGN: Human primary osteoblasts were challenged for 1h with Porphyromonas gingivalis. Tyrosine-phosphorylation of paxillin and focal adhesion kinase (FAK) was examined by Western blotting. Changes in alpha3- and beta1-integrin mRNA expression were quantified by RT-PCR. RESULTS: Tyrosine-phosphorylation of paxillin was proportional to the size of the Porphyromonas gingivalis inoculum. FAK, a potential kinase for paxillin, was not activated. The amount of alpha3- and beta1-integrins, determined by Western blotting, did not vary significantly, while the corresponding mRNA levels fell significantly when a large bacterial inoculum was used. CONCLUSIONS: These results indicate that Porphyromonas gingivalis infection of osteoblasts in vitro triggers tyrosine-phosphorylation of paxillin but not FAK and modify alpha3- and beta1-integrin mRNA expression. This infection thus appears to have different effects on components with essential roles in focal adhesion (paxillin) and cell signalling (FAK and integrins).     

低温保存成骨细胞复合生物活性玻璃陶瓷修复兔下颌骨缺损

目的 观察经低温保存的兔骨膜源性成骨细胞(POBs)的生物学特征,及其与生物活性玻璃陶瓷(BGC)体外复合后修复颌骨缺损的能力。方法 将经鉴定的幼兔骨膜源性成骨细胞置入液氮罐中保存,取冻存6个月的细胞做生物学鉴定,并进行体外培养扩增,然后与BGC复合培养,植入兔下颌骨缺损处,对照组为植入单纯BGC组。术后第2、4、8、12周取材,行X线摄片及组织学检查,观察复合材料的成骨能力。结果 复苏的成骨细胞仍具有典型的成熟成骨细胞的生物学特征,与BGC复合植入体内后,能继续生长增殖并形成骨组织,能较快较好地修复骨缺损。结论 利用冻存复苏的成骨细胞进行组织工程学研究是可行的,细胞与材料复合所形成的组织工程化骨,可望在骨组织的修复与重建中得到更加广泛的应用。     

来源于脂肪组织的基质细胞向成骨细胞分化

目的：研究来源于脂肪组织的基质细胞体外培养和向成骨细胞分化条件。方法：常规方法培养脂肪组织来源的基质细胞．向成骨细胞分化诱导．应用免疫细胞化学办法对细胞进行鉴定．碱性磷酸酶法对分化的成骨细胞鉴定。结果：从成年人的脂肪组织中分离出基质细胞．在体外生长形态类似成纤维细胞。可以维持在未分化状态稳定增殖，体外可持续扩增和传代。在一定的条件下可诱导分化为成骨细胞．分化的细胞表达碱性磷酸酶和I型胶原．在培养皿中也发现钙化斑。结论：脂肪组织中存在的基质细胞能分化为成骨细胞．这种细胞可以做为组织工程的种子细胞。     

Platelet-rich plasma combined with naringin induces osteogenic differentiation of human bone marrow mesenchymal stem cells In vitro北大核心

BACKGROUND: Platelet-rich plasma (PRP) and naringin can both promote proliferation and induce osteogenic differentiation of mesenchymal stem cells. However, their combined use is rarely reported. OBJECTIVE: To observe the effect of PRP combined with naringin on the osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs) in vitro. METHODS: BMSCs at passage 3 were divided into four groups: (1) blank control group, cells were cultured in α-MEM; (2) PRP group, cells were cultured in α-MEM containing PRP; (3) naringin group, cells were cultured in α-MEM containing naringin; and (4) combined group, cells were cultured in a-MEM containing PRP and naringin. The contents oO used PRP and naringin were 12.5% and 50 µg/L respectively. Cell proliferation was detected by MTT assay. Expression oO related genes in hBMSCs was detected by RT-PCR. Alkaline phosphatase staining, collagen type I immunohistochemical staining, and alizarin red staining were used to analyze the osteogenic differentiation of hBMSCs. RESULTS AND CONCLUSION: The proliferation of hBMSCs was increased in each group, especially in the combined group. Cells in all the groups oxcept the blank control group were positive for alkaline phosphatase staining, collagen type I immunohistochemical staining, and alizarin red staining, and the positive effect was more obvious in the combined group. However, negative or weakly positive response was found in the blank control group. At 7 and 14 days, the expression of alkaline phosphatase and collagen type I was significantly higher in the PRP, naringin and combined groups than the blank control group (P < 0.05); at 14 days, the expression of alkaline phosphatase and collagen type I was significantly higher in the combined group than the PRP and naringin groups (P < 0.05). To conclude, PRP combined with naringin can promote the proliferation of hBMSCs and induce the osteogenic differentiation of hBMSCs. Moreover, there is a synergistic effect between PRP and naringin. © 2018, Journal of Clinical Rehabilitative Tissue Engineering Research. All rights reserved.     

Prevention of bone loss by injection of insulin-like growth factor-1 after sciatic neurectomy in rats

Injection of insulin-like growth factor-1 (IGF-1) can prevent bone loss in sciatic nerve transaction rats.We try to investigate the action mechanism of IGF-1 on bone formation.Methods:A total of 40 adu...