Effect of Extract of Seeds of Carthamus tinctorius L. on Mineralization in Periodontal Ligament Cells and Osteoblastic Cells / 대한치주과학회지

The main goal for the treatment of periodontal diseases is the regeneration of lost cementum, bone and connective tissue. Clinical and histological research suggests that it is possible to restore periodontal structures. Seeds of Carthamus tinctorius L. has been used for the treatment of bone fracture and osteoporosis in traditional Korean medicine. The purpose of this study is to examine the effect of extract of seeds of Carthamus tinctorius L. on mineralization in periodontal ligament cells and osteoblastic cells. Periodontal ligament cells were primarily obtained from a extracted premolars with non-periodontal diseases. Osteoblastic cells were obtained from calvariae of a fetal rat. Cells were cultured with DMEM at 37degrees C with 5% CO2 in 100% humidity incubator. Alkaline phosphatase(ALP) level and the number of calcification nodules were examined and western blot analysis using osteonectin was performed. Measurements of ALP levels and calcification nodules showed that extract of seeds of Carthamus tinctorius L. had significantly higher activity than control in all of both cells. In western blot analysis, protein expression of osteonectin indicated that extract of seeds of Carthamus tinctorius L. showed an increased pattern than control in all of both cells. From the above results, it seems that extract of seeds of Carthamus tinctorius L. has excellent effect on mineralization in periodontal ligament cells and osteoblastic cells.

Regulation of ATP-citrate lyase gene transcription

It has been suggested that glucose metabolites and insulin are the most important factors inducing ATP-citrate lyase (ACL) by a high carbohydrate diet. We have used a primary culture of rat hepatocytes to confirm the role of glucose and insulin in terms of ACL gene expression. The results showed that glucose displayed a direct effect on ACL gene expression and the insulin helps the glucose effect. The nucleotide sequences from -512 to -485 of the ACL promoter are highly homologous (70%) to the sequences surrounding the carbohydrate response element (ChoRE) of the S14 gene. The gel retardation analysis using ChoRE of the S14 gene showed that the ACL promoter which contains the ChoRE-like sequence specifically inhibited the formation of the complex by the nuclear proteins isolated from rat liver. To localize the regions which are involved in the regulation of ACL gene expression, transient expression assay using ACL promoter-CAT (chloramphenicol acetyltransferase) constructs containing various lengths of a 5' flanking region of the ACL gene were carried out. The proximal promoter region -419 to -1 containing several potential Sp1 binding sites showed the strong enhancing effect, which increases the transcription of CAT genes in the various cell lines, such as the CHO (Chinese hamster ovary) cell, the HepG2 cell, and primary cultured rat hepatocytes. In response to glucose, among the ACL promoter-CAT constructs, only pNP33-CAT (-1342 to -1) showed a 2.64 fold increase in CAT activity by a high concentration of glucose. The activation of ACL gene expression by glucose seems to be regulated in a complicated manner involving interactions between the contexts of the several sequence elements and various transacting factors, which is not a simple mechanism directed only by a short sequence element.