Secretoneurin, a Neuropeptide, Enhances Bone Regeneration in a Mouse Calvarial Bone Defect Model

BACKGROUND@#This study investigates the effects of a neuropeptide, secretoneurin (SN), on bone regeneration in an experimental mouse model. @*METHODS@#The effects of SN on cell proliferation, osteoblast marker genes expression, and mineralization were evaluated using the CCK-8 assay, quantitative reverse transcriptase polymerase chain reaction (RT-PCR), and alizarin red S staining, respectively. To examine the effects of SN on bone regeneration in vivo, bone defects were created in the calvaria of ICR mice, and 0.5 or 1 lg/ml SN was applied. New bone formation was analyzed by micro-computed tomography (micro-CT) and histology. New blood vessel formation was assessed by CD34 immunohistochemistry. @*RESULTS@#SN had no significant effect on proliferation and mineralization of MC3T3-E1 cells. However, SN partially induced the gene expression of osteoblast differentiation markers such as runt-related transcription factor 2, alkaline phosphatase, collagen type I alpha 1, and osteopontin. A significant increase of bone regeneration was observed in SN treated calvarial defects. The bone volume (BV), BV/tissue volume, trabecular thickness and trabecular number values were significantly increased in the collagen sponge plus 0.5 or 1 lg/ml SN group (p < 0.01) compared with the control group. Histologic analysis also revealed increased new bone formation in the SN-treated groups. Immunohistochemical staining of CD34 showed that the SN-treated groups contained more blood vessels compared with control in the calvarial defect area. @*CONCLUSION@#SN increases new bone and blood vessel formation in a calvarial defect site. This study suggests that SN may enhance new bone formation through its potent angiogenic activity.

Secretoneurin, a Neuropeptide, Enhances Bone Regeneration in a Mouse Calvarial Bone Defect Model

BACKGROUND@#This study investigates the effects of a neuropeptide, secretoneurin (SN), on bone regeneration in an experimental mouse model. @*METHODS@#The effects of SN on cell proliferation, osteoblast marker genes expression, and mineralization were evaluated using the CCK-8 assay, quantitative reverse transcriptase polymerase chain reaction (RT-PCR), and alizarin red S staining, respectively. To examine the effects of SN on bone regeneration in vivo, bone defects were created in the calvaria of ICR mice, and 0.5 or 1 lg/ml SN was applied. New bone formation was analyzed by micro-computed tomography (micro-CT) and histology. New blood vessel formation was assessed by CD34 immunohistochemistry. @*RESULTS@#SN had no significant effect on proliferation and mineralization of MC3T3-E1 cells. However, SN partially induced the gene expression of osteoblast differentiation markers such as runt-related transcription factor 2, alkaline phosphatase, collagen type I alpha 1, and osteopontin. A significant increase of bone regeneration was observed in SN treated calvarial defects. The bone volume (BV), BV/tissue volume, trabecular thickness and trabecular number values were significantly increased in the collagen sponge plus 0.5 or 1 lg/ml SN group (p < 0.01) compared with the control group. Histologic analysis also revealed increased new bone formation in the SN-treated groups. Immunohistochemical staining of CD34 showed that the SN-treated groups contained more blood vessels compared with control in the calvarial defect area. @*CONCLUSION@#SN increases new bone and blood vessel formation in a calvarial defect site. This study suggests that SN may enhance new bone formation through its potent angiogenic activity.

Stimulatory Effects of KPR-A148 on Osteoblast Differentiation and Bone Regeneration

BACKGROUND: Xanthine derivatives have been used to treat a variety of medical conditions including respiratory disease and neural degeneration. However, few studies have reported their effects on bone regeneration. Therefore, we investigated the effects of KPR-A148, a synthetic xanthine derivative on osteoblast differentiation in vitro and bone regeneration in vivo. METHODS: The cytotoxicity of KPR-A148 was evaluated using MC3T3-E1 cells by the 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltertrazolium bromide assay. The effects of KPR-A148 on osteoblast differentiation were examined by alkaline phosphatase staining, Alizarin red S staining, and real-time PCR of osteoblast differentiation marker genes. To investigate the effects of KPR-A148 on in vivo bone regeneration, a KPR-A148-containing collagen sponge was implanted into a mouse calvarial defect and KPR-A148 was injected twice, weekly. Bone regeneration was evaluated quantitatively by micro-CT and qualitatively by hematoxylin and eosin, as well as Masson's Trichrome staining. RESULTS: KPR-A148 did not show toxicity in the MC3T3-E1 cells and promoted osteoblast differentiation in a concentration-dependent manner. 10 µM of KPR-A148 showed the most significant effect on alkaline phospatase staining and matrix mineralization. KPR-A148 increased the expression of osteoblast marker genes in both the early and late stages of differentiation. In addition, KPR-A148 significantly induced new bone formation in the calvarial defect model. CONCLUSION: These results demonstrate that KPR-A148 strongly induces osteoblast differentiation and new bone formation. Therefore, it could be used as a potential therapeutic agent for regenerating bone following its destruction by disease or trauma.

Estimating the medical capacity required to administer mass prophylaxis: a hypothetical outbreak of smallpox virus infection in Korea / 한국역학회지

OBJECTIVES: The aim of this study was to estimate the medical surge capacity required for mass prophylaxis based on a hypothetical outbreak of smallpox.METHODS: We performed a simulation using the Bioterrorism and Epidemic Outbreak Response Model and varied some important parameters, such as the number of core medical personnel and the number of dispensing clinics.RESULTS: Gaps were identified in the medical surge capacity of the Korean government, especially in the number of medical personnel who could respond to the need for mass prophylaxis against smallpox.CONCLUSIONS: The Korean government will need to train 1,000 or more medical personnel for such an event, and will need to prepare many more dispensing centers than are currently available.

Estimating the medical capacity required to administer mass prophylaxis: a hypothetical outbreak of smallpox virus infection in Korea / 한국역학회지

OBJECTIVES@#The aim of this study was to estimate the medical surge capacity required for mass prophylaxis based on a hypothetical outbreak of smallpox.@*METHODS@#We performed a simulation using the Bioterrorism and Epidemic Outbreak Response Model and varied some important parameters, such as the number of core medical personnel and the number of dispensing clinics.@*RESULTS@#Gaps were identified in the medical surge capacity of the Korean government, especially in the number of medical personnel who could respond to the need for mass prophylaxis against smallpox.@*CONCLUSIONS@#The Korean government will need to train 1,000 or more medical personnel for such an event, and will need to prepare many more dispensing centers than are currently available.