Reg Gene Expression in Periosteum after Fracture and Its In Vitro Induction Triggered by IL-6.

The periosteum is a thin membrane that surrounds the outer surface of bones and participates in fracture healing. However, the molecular signals that trigger/initiate the periosteal reaction are not well established. We fractured the rat femoral bone at the diaphysis and fixed it with an intramedullary inserted wire, and the expression of regenerating gene () , which encodes a tissue regeneration/growth factor, was analyzed.

REG Iα gene expression is linked with the poor prognosis of lung adenocarcinoma and squamous cell carcinoma patients via discrete mechanisms.

The aim of the present study was to evaluate the effects of the REG Iα and REG Iβ genes on lung cancer cell lines, and thereafter, the expression of REG family genes (REG Iα, REG Iβ, REG III, HIP/PAP and REG IV) in lung cancer in relation to patient prognosis was evaluated. Lung adenocarcinoma (AD) and squamous cell carcinoma (SCC) cell lines expressing REG Iα or REG Iβ (HLC-1 REG Iα/Iβ and EBC-1 REG Iα/Iβ) were established, and cell number, cell invasive activity, and anchorage-independent cell growth were compared with these variables in the control cells. The expression levels of REG family genes were evaluated by real-time RT-PCR in surgically resected lung cancers, and disease-specific survival (DSS) curves were generated.

Carbon nanotubes induce bone calcification by bidirectional interaction with osteoblasts.

Multi-walled carbon nanotubes (MWCNTs) promote calcification during hydroxyapatite (HA) formation by osteoblasts. Primary cultured osteoblasts are incubated with MWCNTs or carbon black. After culture for 3 weeks, the degree of calcification is very high in the 50 μg mL(-1) MWCNT group.

Secretory osteocalcin as a nondestructive osteogenic marker of tissue-engineered bone.

Background And Purpose: The constructs of mesenchymal stem cells and ceramics form bone tissue after implantation. Therefore, the constructs can include cultured bone (tissue-engineered bone) as bone grafts. However, the selection of constructs, prior to implantation, with high osteogenic potential is still difficult.

The effect of mesenchymal stem cell osteoblastic differentiation on the mechanical properties of engineered bone-like tissue.

Mesenchymal stem cells (MSCs) can give rise to osteoblasts and have therefore been suggested as a cell source for bone engineering. Here we hypothesized that MSC osteoblastic differentiation and maturation can be supported by three-dimensional cultures in collagen hydrogels (hydrogel culture) to ultimately give rise to mechanically robust bone-like tissue. We first compared the osteoblastic differentiation efficiency of MSCs using osteoinductive supplements (β-glycerophosphate, vitamin C, and dexamethasone) in a hydrogel culture and in a two-dimensional culture (2D culture) by assessing surrogate parameters for osteoblastic differentiation, including osteocalcin (OC) secretion and calcium (Ca) deposition.

Osteogenic activity of bone marrow-derived mesenchymal stem cells (BMSCs) seeded on irradiated allogenic bone.

Allogenic bone grafting, a technique used in orthopaedic surgery, has several problems, including low osteogenic activity. To overcome the problem, this study aimed to determine whether in vivo osteogenesis could be enhanced using allogenic irradiated bone grafts after seeding with autologous bone marrow-derived mesenchymal stem cells (BMSCs). The allogenic bone cylinders were extracted from ACI rats and sterilized by irradiation.

Engineering bioartificial tracheal tissue using hybrid fibroblast-mesenchymal stem cell cultures in collagen hydrogels.

We aimed at providing the first in vitro and in vivo proof-of-concept for a novel tracheal tissue engineering technology. We hypothesized that bioartificial trachea (BT) could be generated from fibroblast and collagen hydrogels, mechanically supported by osteogenically-induced mesenchymal stem cells (MSC) in ring-shaped 3D-hydrogel cultures, and applied in an experimental model of rat trachea injury. Tube-shaped tissue was constructed from mixtures of rat fibroblasts and collagen in custom-made casting molds.

Development of a high-specificity enzyme-linked immunosorbent assay (ELISA) system for the quantification and validation of intact rat osteocalcin.

Osteocalcin (OC) exhibits hard tissue-specific expression and binding activity to hydroxyapatite. Therefore, measurement of secreted OC is a very useful index for evaluating osteoblastic differentiation in regenerative bone. In the present study, we established a high-specificity sandwich enzyme-linked immunosorbent assay (ELISA) system for the quantification of intact rat OC, which could be useful for validating tissue-engineered bone samples nondestructively and continuously.

The homeobox gene Hex regulates hepatocyte differentiation from embryonic stem cell-derived endoderm.

We investigated the role of the hematopoietically expressed homeobox (Hex) in the differentiation and development of hepatocytes within embryonic stem cell (ESC)-derived embryoid bodies (EBs). Analyses of hepatic endoderm derived from Hex(-/-) EBs revealed a dramatic reduction in the levels of albumin (Alb) and alpha-fetoprotein (Afp) expression. In contrast, stage-specific forced expression of Hex in EBs from wild-type ESCs led to the up-regulation of Alb and Afp expression and secretion of Alb and transferrin.

Raloxifene: its ossification-promoting effect on female mesenchymal stem cells.

Background: Raloxifene acts like estrogen in preventing bone loss in postmenopausal women, but it selectively activates biological responses in bone tissue. It has a direct effect on osteoblasts' differentiation and bone formation in bone marrow culture. However, the point at which raloxifene has an effect on bone marrow-derived mesenchymal stem cells (MSCs), regardless of sex difference, is not known.

Cell sheet transplantation of cultured mesenchymal stem cells enhances bone formation in a rat nonunion model.

Orthopedic surgeons have long been troubled by cases involving nonunion of fractured bones. This study aimed to enhance bone union by cell sheet transplantation of mesenchymal stem cells. A nonunion model was made in rat femur, and rat bone marrow cells were cultured in medium containing dexamethasone and ascorbic acid phosphate to create a cell sheet that could be scraped off as a single sheet.

Osteocalcin secretion as an early marker of in vitro osteogenic differentiation of rat mesenchymal stem cells.

Osteocalcin (OC) is a bone-specific protein synthesized by osteoblasts that represents a good marker for osteogenic maturation. We examined whether in vitro osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (MSCs) could be simply assessed at earlier stages by monitoring OC secretion into the conditioned medium, rather than measuring OC deposition on the extracellular matrix (ECM), using a sandwich enzyme immunoassay system involving a specific anti-rat OC monoclonal antibody. During a 16-day culture, OC was secreted into the medium of MSCs from day 8 and increased substantially until day 16.

Osteogenic matrix sheet-cell transplantation using osteoblastic cell sheet resulted in bone formation without scaffold at an ectopic site.

We previously reported that in vivo bone formation could be observed in composites of porous hydroxyapatite (HA) scaffolds and cultured mesenchymal stem cells (MSCs). In the present study, we developed a new method for transplantation of cultured MSCs without the necessity of using a scaffold to form bone tissue. MSCs were culture-expanded and lifted as cell sheet structures.

Bone marrow-derived mesenchymal cells can rescue osteogenic capacity of devitalized autologous bone.

In clinical cases, many orthopaedists have been troubled with bone fragility, such as fractures after devitalization therapy for bone tumour, pathological fractures and metastatic tumours. The aim of this study was to determine whether loss of osteogenic capacity of devitalized autologous bones can be rescued using cultured bone marrow-derived mesenchymal cells. A devitalized bone model was produced from rat femur by irradiation and three groups were prepared: intact bone, irradiated bone and irradiated bone combined with cultured mesenchymal cells.

Impact of metabolic syndrome on brachial-ankle pulse wave velocity in Japanese.

The aim of this study was to determine the effect of metabolic syndrome on brachial-ankle pulse wave velocity (baPWV) by using the new guidelines for diagnosis of this syndrome in Japan. We examined 525 men and women without a history of cardiovascular disease or cancer, and an ankle-brachial index < 0.9.

Role of metallothionein isoforms in bone formation processes in rat marrow mesenchymal stem cells in culture.

Temporal changes in mRNAs for metallothionein (MT) isoforms in subcultures of rat marrow mesenchymal stem cells (MSCs) after treatment with dexamethasone were investigated. Both MT-1 and MT-2 mRNA expression in the cultured MSCs with dexamethasone showed maximum levels at d 1, whereas ALP and osteocalcin mRNAs peaked at d 12. MT-3 mRNA was not detected in the cultured MSCs at any time.

Activation of regenerating gene Reg in rat and human hearts in response to acute stress.

Recently, the regenerating gene (Reg) has been documented to play an important role in various regenerating tissues, but it is unknown whether the Reg gene could be activated in the heart. The aim of this study was to reveal the transcriptional activation of Reg in the heart in response to heart stress. We first found REG-1 protein expression in human hearts obtained from autopsied patients who died of myocardial infarction.

Osteogenic potential of cultured bone/ceramic construct: comparison with marrow mesenchymal cell/ceramic composite.

Osteogenesis occurs in porous hydroxyapatite (HA) when porous HA blocks combined with marrow mesenchymal cells are grafted in vivo. In vitro bone formation occurs in HA pores when HA combined with marrow cells is cultured in osteogenic medium containing dexamethasone. This cultured bone/HA construct possesses higher osteogenic ability when it is grafted in vivo.

Prediction of bone mineral density from vitamin D receptor polymorphisms is uncertain in representative samples of Japanese Women. The Japanese Population-based Osteoporosis (JPOS) Study.

Background: Vitamin D receptor (VDR) gene polymorphisms have been inconsistently associated with bone mineral density (BMD). To precisely evaluate the associations between three VDR gene polymorphisms and BMD, we performed a large-scale representative study of the Japanese female population.

Methods: Fifty women were randomly selected from each of the 5-year age stratified populations (15-79 years) in each of the three municipalities examined, as a part of the Japanese population-based osteoporosis (JPOS) baseline study in 1996.

Characterization of the cDNA encoding bullfrog, Rana catesbeiana, osteocalcin and two forms of the protein isolated from bone.

A full-length cDNA clone encoding osteocalcin from the bullfrog, Rana catesbeiana (bone Gla-protein, BGP) has been isolated, and the complete coding sequence for the 100-amino-acid pre-pro-osteocalcin protein was determined. The amino acid sequence of Rana catesbeiana osteocalcin, especially the mature 49-amino acid sequence, is closer to the mammalian than to the fish, Sparus osteocalcin. Rana mature osteocalcin has a similarity of 67% with human or 59% with rat osteocalcin, and only 42% with fish mature osteocalcin.

Osteogenic differentiation of cultured rat and human bone marrow cells on the surface of zinc-releasing calcium phosphate ceramics.

Rat and human bone marrow cells (BMCs) were cultured on a composite ceramic of zinc-containing beta-tricalcium phosphate and hydroxyapatite (ZnTCP/HAP) with a (Ca+Zn)/P molar ratio of 1.60 and varying zinc contents. After a 2-week culture of the BMCs in the presence of beta-glycerophosphate and dexamethasone, many macroscopic mineralized areas with high alkaline phosphatase (ALP) activity were seen on the ZnTCP/HAP ceramic disks.

Enhancement of cell viability in cryopreserved rat vascular grafts by administration of regenerating gene (REG) inducers.

The regenerative capacity of viable cells remaining in cryopreserved vascular allografts is still unclear. Recently, the regenerating gene (REG) has been documented to play an important role in various regenerating tissues. Here we show the possibility of REG induction for the enhancement of cryopreserved vascular allograft viability.