Inhibiton of MMP-13 mRNA expression by Doxycycline combination with Mefenamic Acid in the rat Periodontal ligament cells / 대한치주과학회지

It has been focused on the importance of the host inflammatory response in periodontal pathogenesis and progression, treatment has been introduced to control the host response and the method, which diminishes production and activity of MMP by doxycycline, has been used in periodontal field. MMP is a proteolytic enzyme which plays a major role in tissue destruction and MMP-1 is secreted in the periodontally healthy tissue, while MMP-8, 9, 13, etc in the inflammatory state. Among these, MMP-13 has been discovered lately and reported to degrade primarily type II collagen. Periodontal ligament (PDL) cell plays a role in destruction of periodontal tissue. This study was to evaluate the effect of doxycycline and mefenamic acid, non-steroidal antiinflammatory drug on MMP-13 mRNA expression in the rat PDL cell. Doxycycline concentration of 1~100 microgram/ml was added rat PDL cell and cell activity was measured by MTT assay at day 1 and 3. MMP-13 gene expression was evaluated by RT-PCR after PDL cells were pre-treated for 1 hour with doxycycline (50 microgram/ml) alone or with mefenamic acid (10(-6)M), then added IL-1beta(1.0 ng/ml) and incubated for 16 -18 hours. The results are as follows: 1. Cell activity decreased significantly at 24 and 72 hours in 100 microgram/ml (p<0.05). 2. Level of MMP-13 mRNA was in 202% increase by IL-1beta and in pre-treating doxycycline group, expression of IL-1beta induced MMP-13 mRNA was inhibited by 31% than IL-1beta treated only. 3. Mefenamic acid did not inhibit on the expression of IL-1beta induced MMP-13 mRNA, while mefenamic acid in combination with doxycycline inhibited the expression by 41% compared to only IL-1beta stimulation. These results suggest that doxycycline synergistically inhibit the expression of IL-1beta induced MMP-13 mRNA in combination with mefenamic acid.

Inhibition of MMP-13 mRNA expression by ginseng saponin in fetal rat calvarial cells / 대한치주과학회지

There is a potential role of collagenase-3 in alveolar bone loss and periodontal disease progression, we need to develope or find chemotherapeutic drugs or herbal agents which may regulate the expression of MMP-13. Ginseng saponin, one of the major components of Korea ginseng(panax ginseng) root, has many various biologic effects, such as cytotoxic effect, tumoricidal effects, cytokine regulations, and protein biosynthesis effect. The purpose of this study was to determine the effects of Korea red ginseng saponin on MMP-13 gene expression in osteoblasts. The experimental groups were cultured with ginseng saponin in concentration of 1.0, 10, 25, 50, 100, 250 and 500microgram/ml for MTT assay. Primary rat calvarial cells were pre-treated for 1 hour with ginseng saponin(100 microgram/ml) and then stimulated with IL-1beta(1.0ng/ml) and PTH (10 nM). MMP-13 gene expression was evaluated by RT-PCR. The results were as follows: Ginseng saponin was cytotoxic to osteoblast at concentration exceeding 250microgram/ml for longer than 24 hours in tissue culture(p<0.01). In RT-PCR analysis, steady state MMP-13 mRNA levels were increased approximately 350% by IL-1beta, and 400% by PTH when normalized to untreated control. IL-1beta-indued MMP-13 mRNA expression was reduced 50% by pre- treatment with ginseng saponin. But ginseng saponin didn't inhibit MMP-13 expression from PTH stimulated cells. This results suggest that ginseng saponin inhibit IL-1beta-indued MMP-13 mRNA expres- sion.

Effects of the MnCl2 on bone formation in fetal rat calvarial cell / 대한치주과학회지

Chronic exposure to high levels of manganese (Mn) leads a pronounced and debilitating disorder known as manganism. Research on the toxic manifestation of manganese have focused primarily on its neurological effects because exposure to high levels of the metal produces a distinct and irreversible extrapyramidal dysfunction resembling the dystonic movements associated with Parkinson's physiological and biochemical systems in the body. The purpose of this study is to determine the effects of Mn on mineralization in primary rat calvarial cells. The experimental groups were in concentration of 0, 10, 30 and 60 micrometer. The results were as follows: 1. ALP activity was decreased in concentration of 30 and 60 micrometer (p<0.01). 2. Bone nodule formation was depressed in concentration of 30 and 60 micrometer at day 14 and 21 (p<0.01). 3. RT-PCR results showed an altered expression of bone matrix proteins. These result suggested that manganese might decrease or alter the expression of the osteoblast phenotype.

Effect of chitosan on bone matrix expression and mineralization in primary rat calvarial cell / 대한치주과학회지

Periodontal therapy has dealt primarily with attempts at arresting progression of disease, however, more recent techniques have focused on regenerating the periodontal ligament having the capacity to regenerate the periodontium. The effect of chitosan, a carbohydrate biopolymer extracted from chitin, on periodontal ligament regeneration is of particular interest. The purpose of this study was to evaluate the effect of chitosan on the expression of extracellular matrix proteins in primary rat calvarial cells in vitro. In the control group, cells was cultured with BGJb media. In the experimental groups, cells were cultured with chitosan in concentration of 0.01, 0.1, 1.0 and 2.0 mg/ml. Then each group was characterized by examining alkaline phosphatase activity at 3 and 7 days, and the ability to produce mineralized nodules of rat calvarial cells at 14 and 21 days. Synthesis of type I collagen (COL-I), osteocalcin (OCN), bone sialoprotein (BSP) was evaluated by RT-PCR at 14 days. The results were as follows: 1. Alkaline phosphatase activity was significantly higher in the concentration of chitosan 0.01mg/ml, 0.1mg/ml and 1.0mg/ml compared to control (p<0.05). 2. The percentage of mineralized bone nodule was more in the concentration of chitosan 0.1mg/ml and 1.0 mg/ml than the control. 3. At 14 day culture, the expression of OCN was increased by chitosan in concentration of 1.0 mg/ml and 2.0 mg/ml. These results suggested that chitosan in concentration of 0.1 and 1.0 mg/ml stimulate the extracellular matrix of primary rat calvarial cells and may facilitate the formation of bone.