Effect of recombinant human fibroblast growth factor 21 on the mineralization of cementoblasts and its related mechanism / 华西口腔医学杂志

OBJECTIVES@#To investigate the effect of recombinant human fibroblast growth factor 21 (rhFGF21) on the proliferation and mineralization of cementoblasts and its mechanism.@*METHODS@#Hematoxylin eosin, immunohistochemical staining, and immunofluorescence were used to detect the expression and distribution of fibroblast growth factor 21 (FGF21) in rat periodontal tissues and cementoblasts (OCCM-30), separately. Cell Counting Kit-8 was used to detect the proliferation of OCCM-30 under treatment with rhFGF21. Alkaline phosphatase staining and Alizarin Red staining were used to detect the mineralization state of OCCM-30 after 3 and 7 days of mineralization induction. The transcription and protein expression of the osteogenic-related genes Runx2 and Osterix were detected by real-time quantitative polymerase chain reaction (PCR) and Western blot analysis. The expression levels of genes of transforming growth factor β (TGFβ)/bone morphogenetic protein (BMP) signaling pathway in OCCM-30 were detected through PCR array analysis.@*RESULTS@#FGF21 was expressed in rat periodontal tissues and OCCM-30. Although rhFGF21 had no significant effect on the proliferation of OCCM-30, treatment with 50 ng/mL rhFGF21 could promote the mineralization of OCCM-30 cells after 7 days of mineralization induction. The transcriptional levels of Runx2 and Osterix increased significantly at 3 days of mineralization induction and decreased at 5 days of mineralization induction. Western blot analysis showed that the protein expression levels of Runx2 and Osterix increased during mineralization induction. rhFGF21 up-regulated Bmpr1b protein expression in cells.@*CONCLUSIONS@#rhFGF21 can promote the mineralization ability of OCCM-30. This effect is related to the activation of the TGFβ/BMP signaling pathway.

Research progress on the regulatory mechanism of estrogen in periodontal ligament cells repair and the reconstruction of periodontal tissue / 口腔疾病防治

@#Periodontium regeneration and repair is a controversial and difficult point in the treatment of periodontosis. The proliferation, differentiation, migration and adhesion of periodontal ligament cells and the dynamic relationship between periodontal ligament cells and their extracellular matrix proteins are the basis of periodontium morphological reconstruction, functional maintenance and tissue repair. This article reviews the mechanism of estrogen-regulated periodontal membrane fine repair and periodontal tissue reconstruction to provide the basis for follow-up research on the treatment of periodontitis and the promotion of periodontal tissue repair and reconstruction by exogenous estrogen-mediated periodontal membranes. Under the regulation of certain concentrations of estrogen, the proliferation and differentiation ability of periodontal ligament stem cells (PDLSCs) and bone mesenchymal stem cells (BMSCs) to other periodontal ligament cells were enhanced. At the same time, PDLSCs, BMSCs, human periodontal ligament fibroblasts (HPLFSs), osteoblasts and cementoblasts synthesized and secreted collagen I (COLI), osteopontin (OPN), bone sialoprotein (BSP) and osteocalcin (OCN) into the extracellular matrix. They interact with fibronectin (FN) and cementum attachment protein (CAP) in the extracellular matrix to form a variety of chain complexes and regulate each other, thus promoting the growth, migration, adhesion and fibrosis of periodontal ligament cells, repairing the collagen fiber skeleton of the periodontal ligament and adhering the two ends to the new cementum and the inherent alveolar bone.

Expression characteristics of Wnt5a in different periods of cementum development and its effect on differentiation of cementoblasts of mice / 吉林大学学报(医学版)

Objective: To study the expression characteristics of Wnt5a in cementum of the mice after birth and the effect of Wnt5a on the differentiation of cementoblasts in vitro, and to illuminate the mechanism of Wnt noncanonical signaling in regulating the tooth development. Methods: The postnatal Kunming mice at the days 0. 5, 4. 5, 12. 5, 18. 5, 24. 5 and 30. 5 after birth were selected and divided into various groups by different time points (n=3). The mice were sacrificed and the lower first molar and peridentium were prepared. Immunohistochemical staining was used to detect the expression characteristics of Wnt5a in tooth and peridentium of the mice. The OCCM30 cells were divided into control group and experiment group. 200 μg · L-1 recombinant Wnt5a protein were added in experiment group, and nothing was added in control group; the total RNA in the cells was exrracted. The relative expression levels of Ocn, Opn, Alp, Bsp, Wnt5a, and Runx-2 genes in the OCCM30 cells in two groups were detected by RT-PCR method. Results: At the day 0. 5 after birth, the expression of Wnt5a in the lower first molar tooth germ was negative. At the day 4. 5 after birth, the expression of Wnt5a in ameloblasts and odontoblasts were positive. At the day 16. 5 after birth, the expression of Wnt5a in cementoblasts was positive. At the days 20.5 - 30.5 after birth, the expressions of Wnt5a in odontoblasts and periodontal ligament cells were positive. Compared with control group, the relative expression levels of Ocn and Alp gene in the OCCM30 cells in experiment group were decreased (P<0. 05). Conclusion: The expression of Wnt5a is regular at different tooth developmental stages after birth. Wnt5a can reduce the expression of differentiated genes and play an important role in the growth of cementum.

Cemento dental: aspectos atuais de interesse para o clínico / Dental cementum: current aspects to the clinicians

Embora tenha havido avanço no entendimento da homeostase do cemento dental, o papel deste tecido e sua biologia permanecem não completamente elucidados. Este estudo buscou fornecer informações sobre os conhecimentos mais recente relacionados à biologia do cemento dental, com o objetivo de discutir o papel exercido por este tecido em condições não fisiológicas nos tecidos periodontais. Devido aos avanços na exploração do tecido ósseo, que compartilha diversas características similares, a pesquisa abrangente sobre o cemento dental tem sido encorajada, a fim de esclarecer a função completa deste tecido na homeostase periodontal e regeneração. Desta forma, no presente trabalho, sempre que possível será feito um paralelo entre osso alveolar e cemento dental. O desenvolvimento de metodologias e técnicas celulares e moleculares avançadas possibilitou um melhor entendimento do comportamento do cemento em situações diversas, como quando em situações patológicas, como a doença periodontal, e até mesmo frente à regeneração tecidual. Ademais, estudos clínicos e em modelo animal demonstraram resultados em relação à formação de cemento em abordagens regenerativas. No entanto, sugere-se que estudos posteriores possam contribuir para um melhor conhecimento sobre o cemento e o perfil celular dos cementoblastos e cementócitos, bem como suas interações para fornecer novos insights para o desenvolvimento de terapias eficientes e mais previsíveis para regeneração dos tecidos periodontais. Apesar dos avanços dos estudos clínicos e laboratoriais, pôde-se concluir que inúmeras questões referentes à biologia do cemento permanecem não esclarecidas.

Although some progress has been made to understand dental cementum homeostasis, its role and biology remains not completely elucidated. This study aimed to provide information on the recent knowledge related to the dental cementum biology, in order to discuss the role of this tissue in physiological and non-physiological conditions in the periodontal tissues. Due to advances in the exploration of bone tissue, which shares several similar features, comprehensive research on dental cementum has been encouraged in order to clarify the complete function of this tissue in periodontal homeostasis and regenerative approach. Novel methodologies and advanced cellular and molecular techniques provided better understanding of cementum in different circumstances, as pathological situations such as periodontal disease and even tissue regeneration. In addition, clinical and animal model designs show positive outcomes to cementum formation in regenerative approaches, however, it is suggested that further studies may contribute to better understand cementum tissue and cementoblasts and cementocytes profile, as well as their interactions, providing new insights to develop efficient and more predictable therapies for periodontal tissue regeneration. Despite advances in clinical and laboratory studies, it can be concluded that many questions regarding the cementum biology remain unclear.