The Src family non-receptor tyrosine kinases (SFK) participate in many aspects of cell function, such as the differentiation, the cell polarity and the migration. Recent studies with gene-targeted mice have revealed that Src plays a key role in osteoclast differentiation, however, the functions of SFK in osteoblasts are not entirely clear at present. In the present studies, we evaluated SFK for regulating the osteoblast functions including cell migration and growth using osteoblast-like MC3T3-E1 cells. Cell migration was significantly blocked in the presence of PP2 (a synthetic Src family kinase specific inhibitor) or LY294002 (a selective inhibitor for PI3-kinase). Further studies demonstrated that PP2 abolished the phosphorylation of AKT and ERK1/2, suggesting the significant role for SFK/AKT/ERK1/2 signaling cascade in the migration of osteoblasts. It is, however, neither PP2 nor LY294002 affected osteoblasts cell proliferation, implicating the signaling cascade involving SFK and PI3-kinase would be distinct from that regulates cell growth. These results suggest that SFK plays a key role in facilitating osteoblasts cell migration by activating AKT and ERK1/2 as potential down-stream targets.
The purpose of this study was to evaluate the effects of superficial properties of implants and PRP on the alveolar bone around dental implants. Bone defects, similar to tooth-extracted holes, were made in 6 beagles, and dental implants with various superficial characteristics (Ha-coated and acid-blasted) were implanted at the center of bone defects. PRP and autologous bone were filled around the implants. Calcein- and alizarin red-labeling was performed, and new bone formation was serially observed by confocal laser scanning microscopy (CLSM) and micro-focus X-ray CT. As a result, newly formed bone was partially observed around the implant body 2 weeks after surgery, and there was a callus 4 weeks after surgery. Eight weeks after surgery, newly formed bone increased, and bone alteration was observed around the implant body. These findings suggested that application of PRP to autologous bone transplantation in bone defects induced early new bone formation.
Saliva is carrying out work important for a health maintenance. Even if salivary glands get damaged, the method for recovering is not learned. This study was examining the effective recovery method of the salivary glands which got damaged. Adult male Wistar rats were used in this study. In the experimental group, right and left submandibular glands were cut sagittally, and the mesial portions removed. Each residual salivary gland was sutured to unite cut the edges. Surgery was not performed on the control group. Analysis included salivary gland weight, volume, findings on H-E stain ,saliva secretion ability, and gene analysis. Submandibular gland of an experimental group became large volume eight weeks after, with keeping secrete saliva function. Reservation of the number of acinar cells needed and discharge of enough saliva were considered to have promoted the regeneration of a submandibular gland. When the damaged rats salivaly gland were connected to opposite at each other, redual acinar cells proliferation, and the saliva was possible to discharge. These data were considered to have promoted the regeneration of a submandibular gland.