Background Facial nerve injury often results in poor prognosis due to the challenging process of nerve regeneration. Neuregulin-1, a human calmodulin, is under investigation in this study for its impact on the reparative capabilities of Dental Pulp Stem Cells (DPSCs) in facial nerve injury. Methods Lentivirus was used to transfect and construct Neuregulin-1 overexpressed DPSCs. Various techniques assessed the effects of Neuregulin-1: osteogenic induction, lipid induction, Reverse Transcription Polymerase Chain Reaction, Western Blot, Cell Counting Kit-8 assay, wound healing, immunofluorescence, Phalloidin staining, nerve stem action potential, Hematoxylin-eosin staining, transmission electron microscopy, and immunohistochemistry. Results Neuregulin-1 effectively enhanced the proliferation, migration, and cytoskeletal rearrangement of DPSCs, while simultaneously suppressing the expression of Ras homolog gene family member A (RhoA) and Microfilament actin (F-actin). These changes facilitated the neural differentiation of DPSCs. Additionally, in vivo experiments showed that Neuregulin-1 expedited the restoration of action potential in the facial nerve trunk, increased the thickness of the myelin sheath, and stimulated axon regeneration. Conclusion Neuregulin-1 has the capability to facilitate the repair of facial nerve injuries by promoting the regenerative capacity of DPSCs. Thus, Neuregulin-1 is a significant potential gene in the reparative processes of nerve damage.

背景:牙髓干细胞由于其来源广泛、免疫原性低并具有优秀的向神经系统细胞分化的能力,因此对神经系统疾病有潜在的治疗价值.目的:总结牙髓干细胞神经源性标记物的表达特点,回顾以往牙髓干细胞向神经系统细胞分化的研究进展,为其应用于临床神经系统疾病的治疗提供研究基础.方法:应用计算机以"牙髓干细胞、神经分化、神经细胞标记物、神经"为中文检索词,以"dental pulp stem cells,neuro-differentiation,nerve biomarker,nerve"为英文检索词,检索中国知网、万方数据和PubMed数据库中的相关文献,根据纳入标准并筛选,最终选择85篇文献进行综述.结果 与结论:①牙髓干细胞向神经细胞分化过程中所表达的几种常用的神经标记物主要包括:巢蛋白、性别决定基因相关转录因子2、βⅢ微管蛋白、胶质纤维酸性蛋白、微管相关蛋白2、S100钙结合蛋白B、神经元特异性烯醇化酶、神经元特异性核蛋白,文章总结归纳了上述标记物的特点、表达的时期以及在牙髓干细胞神经向分化研究中的应用情况.②目前研究表明,判断牙髓干细胞向神经细胞分化是否成功,需要结合形态学特征以及分化后细胞的功能进行综合判断,同时使用单一标记物很难专门识别单个细胞谱系,因此,未来有必要将多个标记物应用于一种细胞类型进行分析.③文章还从生长因子、信号通路及生物支架等方面介绍了牙髓干细胞向神经样细胞分化的方法,以期为诱导牙髓干细胞神经向分化研究提供理论参考.

ObjectiveThe aim of this research was to investigate the effect of vascular endothelial growth factor A (VEGFA)-overexpressing rat dental pulp stem cells (rDPSCs) combined with laminin-coated and yarn-encapsulated poly(l-lactide-co-glycolide) (PLGA) nerve guidance conduit (LC-YE-PLGA NGC) in repairing 10 mm facial nerve injury in rats.Study DesignrDPSCs isolated from rat mandibular central incisor were cultured and identified in vitro and further transfected with the lentiviral vectors (Lv-VEGFA). To investigate the role and mechanisms of VEGFA in neurogenic differentiation in vitro, semaxanib (SU5416), Cell Counting Kit-8 (CCK-8), real-time quantitative polymerase chain reaction (qPCR) and Western blotting were performed. Ten-millimeter facial nerve defect models in rats were established and bridged by LC-YE-PLGA NGCs. The repair effects were detected by transmission electron microscopy (TEM), compound muscle action potential (CMAP), immunohistochemistry and immunofluorescence.ResultsExtracted cells exhibited spindle-shaped morphology, presented typical markers (CD44+CD90+CD34−CD45−), and presented multidirectional differentiation potential. The DPSCs with VEGFA overexpression were constructed successfully. VEGFA enhanced the proliferation and neural differentiation ability of rDPSCs, and the expression of neuron-specific enolase (NSE) and βIII-tubulin was increased. However, these trends were reversed with the addition of SU5416. This suggests that VEGFA mediates the above effects mainly through vascular endothelial growth factor receptor 2 (VEGFR2) binding. The LC-YE-NGC basically meet the requirements of facial nerve repair. For the in vivo experiment, the CMAP latency period was shorter in DPSCS-VEGFA-NGC group in comparison with other experimental groups, while the amplitude was increased. Such functional recovery correlated well with an increase in histological improvement. Further study suggested that VEGFA-modified DPSCs could increase the myelin number, thickness and axon diameter of facial nerve. NSE, βIII-tubulin and S100 fluorescence intensity and immunohistochemical staining intensity were significantly enhanced.ConclusionVEGFA-modified rDPSCs combined with LC-YE-PLGA NGCs have certain advantages in the growth and functional recovery of facial nerves in rats.

神经损伤是临床中的常见及多发疾病,可分为周围神经损伤(peripheral nervous injury,PNI)和中枢神经损伤(central nervous injury,CNI),目前采取的治疗方法主要有自体神经移植、异体神经移植、细胞促进疗法、组织工程法等.相比于其他三种方法,组织工程法的发展将从根本上解决组织和器官缺损所致的功能障碍或丧失治疗等问题,以达到完美的形态修复.神经调节素-1(neuregulin-1,NRG-1)作为一种经典的生长和分化因子,应用到组织工程上可以抑制细胞衰老、促进细胞增殖和分化,并且能够通过相关信号通路促进PNI和CNI后的神经修复.本文主要说明NRG-1的结构、功能及其在PNI与CNI修复中发挥的作用及作用机制.

牙髓干细胞(dental pulp stem cells,DPSCs)是一类具有高度增殖、多向分化潜能的成体干细胞,其来源丰富,具有提取较为便捷、伦理争议较小的优势.由于DPSCs具有多向分化的潜能,可以在一定条件下诱导成神经向分化,在神经损伤的修复和神经遗传性疾病的治疗等方面应用前景广阔.神经营养素(neurotrophin,NT)是一类能够促进轴突生长、利于神经细胞分化与存活的由神经所支配的组织或细胞产生的蛋白质分子,可以分为神经营养因子(neurotrophic factor,NTFs)家族、胶质细胞源性神经营养因子(glial cell-derived neurotrophic factor,GDNF)家族、白细胞介素-6(interleukin-6,IL-6)细胞因子家族、成纤维细胞生长因子(fibroblast growth factor,FGF)家族等,NT作为促进神经细胞分化的营养因子,也能够促进干细胞神经向分化,其对DPSCs神经向分化有一定的引导作用.该文简要介绍了NT在促进细胞神经向分化方面的作用,就NT对DPSCs神经向分化的影响和应用前景进行概述.

Peripheral nerve injury (PNI) is a common disease in the oral cavity that can easily lead to loss of function and abnormal appearance. The application of dental pulp stem cells (DPSCs) combined with tissue engineering in the repair of PNI is a research hotspot. DPSCs have the advantages of abundant sources, simple extraction, low immunogenicity and a high proliferation rate in vitro. They can differentiate into Schwann cells (SCs). SCs can induce autophagy and secrete key neurotrophic factors, such as nerve growth factor, brain-derived neurotrophic factor, ciliary neurotrophic factor and glial cell-derived neurotrophic factor. SCs are beneficial for the repair of nerve injury. DPSCs in different periods have differences in immune regulation, anti-inflammatory effects, expression of neural markers, angiogenesis and so on, which provide more diversified choices for nerve repair. At present, the introduction of tissue engineering provides a more controllable and improved microenvironment for DPSCs, which is conducive to the application and development of DPSCs in regenerative medicine and tissue engineering. However, there are still many problems to be solved, such as the selection of stem cells, functional link recovery, uncontrollable direction of axon regeneration, regulation of the peripheral nervous system and mechanism of repair.

Oral squamous cell carcinoma (OSCC) is a common cancer that develops from oral epithelial cells, it has a high incidence, mortality and teratogenic rate, which poses a serious threat to people's life and health.The Hippo signaling pathway plays a key role in tumorigenesis, regulation of stem cell homeostasis, tissue regeneration, and organ size control. In OSCC, activation of Hippo signaling pathway can inhibit malignant biological behavior, epithelial mesenchymal transformation and distant metastasis of tumors, and improve the survival rate of patients. Considering the importance of the Hippo signaling pathway in the development of cancer, this paper summarized the composition and regulatory mechanism of Hippo pathway, elaborated the role of Hippo signaling pathway in the occurrence and development of OSCC.At the same time, make a simple generalization about the potential therapeutic approaches and strategies to reduce the risk of drug resistance for OSCC patients targeting this pathway.

目的:研究二甲双胍(metformin,MF)对成牙骨质细胞(cementoblasts,CB)增殖、分化、矿化能力的影响,为临床牙骨质缺损、牙根修复提供新的用药思路.方法:对成牙骨质细胞系OCCM-30分别给予不同浓度的MF培养,MTS法检测CB的增殖;实时荧光定量PCR法(quantitative real-time polymerase chain reaction,qPCR)及蛋白免疫印迹法检测骨涎蛋白(bone sialoprotein,BSP)和Runt相关转录因子2(runt-related transcription factor 2,Runx2)在基因及蛋白层面的表达;碱性磷酸酶(alkaline phosphatase,ALP)活性测定及茜素红染色法检测MF对CB矿化的影响.结果:不同浓度的MF作用于OCCM-30细胞24、48、72小时后,200μmol/L和400μmol/L MF组对细胞的增殖能力具有促进作用(P＜0.05),高浓度1600μmol/L MF组在作用细胞72小时后对细胞增殖产生抑制作用(P＜0.05).与对照组相比,用200μmol/L MF处理OCCM-30细胞12、24、48小时后,Runx2和BSP mRNA及蛋白的表达量明显增高(P＜0.05).200μmol/L MF作用OCCM-30细胞3天时ALP活性高于对照组(P＜0.05),作用7天时则无统计学差异(P＞0.05).200μmol/L MF作用OCCM-30细胞21天后,矿化结节形成百分率明显高于对照组(P＜0.01).结论:一定浓度范围内的MF能促进CB的增殖、分化及矿化,提高CB的成骨能力.