간행물

International Journal of Oral Biology KCI 등재후보

권호리스트/논문검색
이 간행물 논문 검색

권호

Vol. 30 No. 4 (2005년 12월) 6

1.
2005.12 구독 인증기관 무료, 개인회원 유료
Resveratrol (3,4',5-trihydroxy-trans-stilbene), a naturally occuring polyphenol compound which present in the skin of grapes and red wine has been considered to posses chemopreventive and antioxidant properties. However, little is known about the cellular actions by which resveratrol mediates its therapeutic effects. In this study, the effect of resveratrol on cell proliferation and induction of apoptosis in human osteogenic sarcoma (HOS) cells was investigated. IC50 value was determined to be approximately 60μg/mℓ. Chromosomal DNA framgmentation analysis showed the appearance degraded DNA in time-and dose-dependent manner upon treatment of resveratrol. In order to observe the molecular mechanism involved in resveratrol-induced apoptosis, Western blot analysis was performed. We observed the decrease in the level of procaspase-3, the zymogen form of active caspase-3 in resveratrol-treated cells. This result implies that caspase-3 is activated upon treatment of resveratrol. The activation of caspase-3 was confirmed by the cleavage of poly(ADP-ribose) polymerase. Taken together, our data demonstrate that resveratrol has anti-proliferative effect on HOS cells and induced apoptosis through activation of caspase-3 and PARP cleavage.
4,000원
2.
2005.12 구독 인증기관 무료, 개인회원 유료
Various aspects of antioxidant activity in vitamin C were evaluated in this study. Relatively high level of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was detected in vitamin C, but not in non-antioxidative vitamin, vitamin B1. Vitamin C also reduced the production of lipid peroxidation in Chinese hamster lung fibroblast (V79-4) cells with IC50 value of 4μg/mℓ. Vitamin B1 showed comparable reduction in lipid peroxidation products (IC50 value was about 10μg/mℓ). It was shown that vitamin C also dose-dependently enhanced the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in V79-4 cells, and these effects were not observed in vitamin Bl-treated cells. Our data suggest that well-known antioxidant vitamin C involved in direct activation of SOD, CAT and GPX.
4,000원
3.
2005.12 구독 인증기관 무료, 개인회원 유료
Thrombin-induced platelet microbicidal proteins (tPMP) are antibacterial proteins released when platelets are stimulated by thrombin. It has been reported that tPMP has antibacterial activity against various bacterial species including causative agents of infective endocarditis. Most of the oral streptococci have resistance to the killing by tPMP and this fact may play an important role as a virulence factor in infective endocarditis. However, the susceptibility and resistance mechanism of oral streptococci for tPMP have not been revealed yet. In this study, the killing mechanism of tPMP for oral streptococci has been investigated. Streptococcus rattus BHT, a susceptible strain, and Streptococcus gordonii DL1, a resistant strain, have been used in this study. tPMP was isolated from platelet after stimulation with thrombin. Cell membrane depolarization was examined with 3,3'-dipropylthiodicarbocyanine iodide (DiSC₃), membrane potential-sensitive cyanine dye, by fluorescence spectrophotometry. The permeabilization of cell membrane by tPMP was investigated with propidium iodide (PI) by flow cytometry. tPMP susceptible S. rattus BHT showed the increase of the DiSC₃fluorescence level meaning depolarization of cell membrane and increase of the uptake of PI which means permeabilization of cell membrane. However, tPMP resistant S. gordonii DLI did not show depolarization and permeabilization. These results indicate that the increasing depolarization and permeabilization of oral streptococcal cell membrane are associated with the bactericidal activity of tPMP.
4,000원
4.
2005.12 구독 인증기관 무료, 개인회원 유료
In the present study, performances of several in vitro maturation (IVM) systems for porcine follicular oocytes were evaluated, and an efficient chemically defined IVM system for porcine oocytes was proposed. The proposed one-step culture system supplemented with polyvinylalcohol (PVA) gave competitive efficiencies in terms of oocyte maturation and blastocyst development after parthenogenetic activation and in vitro culture, compared with the conventional two-step culture system by a supplementation of porcine follicular fluid (pFF). Additionally, it is identified that the proposed chemically defined one-step culture system yielded the comparable level of blastocyst production to the conventional maturation system in porcine somatic cell nuclear transfer (SCNT). Therefore, one can eliminate un-expected effects accompanied by supplementation of pFF. No medium replacement during whole maturation period is an additional benefit by applying this new system. Thus, these data support that the developed PVA supplemented chemically defined one-step IVM system for porcine follicular oocyte might be used in porcine SCNT program.
3,000원
5.
2005.12 구독 인증기관 무료, 개인회원 유료
Although it has been known that TGF-β1 acts as a crucial cofactor in osteoclast differentiation, its mode of action is still unclear. In the present study, we studied the effect of TGF-β1 on the differentiation of osteoclast depending on the developmental stages. Murine bone marrow cells were induced to differentiate into mature osteoclasts in the presence of receptor activator of NF-xβ ligand (RANKL) and macrophage colony stimulating factor (M-CSF). In the early stage of the differentiation TRAP(-) mononuclear precursor cells were obtained from nonadherent M-CSF dependent bone marrow cells, which further differentiated into mature osteoclasts. TGF-β1 stimulated osteoclast differentiation, which was stronger when cells were stimulated by TGF-β1 in the early stage than the later differentiation. TGF-β1 increased the expression of RANK and synergistically stimulated RANKL-induced activation of NF-xβ MAP kinase in TRAP(-) mononuclear precursor cells. These results suggest that activation of osteoclast differentiation by TGF-β1 may be ascribed to the both increased expression and activation of RANK in the osteoclast differentiation, especially in the early stage of differentiation.
4,000원
6.
2005.12 구독 인증기관 무료, 개인회원 유료
Osteoclasts are multinucleated cells with bone resorbing activity and differentiated from hematopoietic cell lineages of monocyte/macrophages in the presence of receptor activator of NF-xB ligand (RANKL) and M-CSF. However, the exact molecular mechanisms through which RANKL stimulates osteoclastogenesis remain to be elucidated. Here we report that activation of cAMP-response elementbinding protein (CREB) is not involved in osteoclastogenesis from osteoclast precursors in response to RANKL. RANKL induced CREB activation in osteoclast precursors. Using pharmacological inhibitors, we found that RANKL-induced CREB activation is dependent on p38 MAPK pathways. We also found that ectopic expressions of wild type and dominant negative forms of CREB in osteoclast precursors did not affect RANKL-induced osteoclast formation and bone resorbing activity. Furthermore, dominant negative forms of CREB did not alter the expression levels of osteoclast-specific marker genes. Taken together, these data suggest that CREB is dispensable for differentiation and resorbing activity of osteoclasts.
4,000원