• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.706-714
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• 2021

Chemical scavenging of reactive oxygen species (ROS) is considered a major mechanism of antioxidant effects, but preventing ROS generation can be more efficient in attenuating oxidative damage. In this study, the extracts of plants, Solanum lycopersicum, Ailanthus altissima, Equisetum arvense, and Oenothera biennis, were tested to determine whether their antioxidative effects are driven by the prevention of superoxide generation from mitochondria, a major ROS generator. While all the extracts efficiently attenuated the elevation of ROS levels in human fibroblasts and inflammation-induced mice, those of S. lycopersicum, A. altissima, and O. laciniata only suppressed mitochondrial ROS generation and reduced levels of lipofuscin and lipid peroxidation. Furthermore, the extracts of A. altissima and O. laciniata extended the lifespan of fruit flies. Our results suggest that plant extracts with anti-oxidative effects differ in their ability to prevent ROS generation, which may be associated with the attenuation of oxidative damage in cells and animal tissues.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.2
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• pp.146-158
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• 2002

The purpose of this study was to investigate the effects of Nd:YAG laser on mechanically exposed pulp of dog by the observation of pulpal inflammatory change and heal process including dentinal bridge, structural changes of fibroblasts of thr remaining vital pulp tissue. In experimental group 1, the exposed pulps were irradiated with Nd:YAG laser(3W, 30Hz, 0.2sec) for $2{\sim}3$ second followed by capped with aluminium tin foil. In group 2 and group 3, the exposed pulps were irradiated with Nd:YAG laser via contact(Group 2) and non-contact(Group 3) methods followed by capped with calciumhydroxide paste. The animal were sacrificed at the intervals of 3, 7, 14 and 30days for histologic evaluation. The results were as follows : 1. The dentinal bridges were formwd more fast and broadly in the experimental group 1 and 2 than other groups, but there were no histologic differences in the degree of their formation among control group, experimental group 1. 2. Odontoblastic activities at amputated pulp was increased in the experimental group 2, 3 than other group but there no histologic difference in the odontblastic activitiy among control group, experimental group 1. 3. The infalmmation was severe at the postoperative 1 week of all groups, but its condition subsideed with time elapsed. At the postoperative 3, 7 days, its condition in experimental group 2, 3 were less severe than in the group 1. 4. There were no histologic differences between the experimental group 2 and 3 according to the degree of dentin bridge formation.

• The korean journal of orthodontics
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• v.34 no.1 s.102
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• pp.71-81
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• 2004

In this study, we attempt to investigate the mechanisms by which PDL cells regulate osteoclast formation and also tc know whether PDL retained their characteristic phenotype during tooth eruption and interdental separation. Rats were prepared at developmental days 21 (pre-root formation), 27(toot development), 34(advanced root formation/eruption) and at later times(adult rats). To induce severe resorption state of alveolar bone and tooth root, interdental separation with brass wire was performed between the lower first and second molars for 2 weeks in adult rats. Rat mandibles were demineralized and embedded in paraffin, and horizontal and frontal section were prepared for immuno-histochemical analysis using PDL-specific protein 22 (PDLs22), receptor activator of NFKB ligand (RANKL) and osteoprotegerin (OPG) antibodies. 1. Root formation and eruption stage of tooth development. 1) PDLs22 immunolocalization was observed in tooth follicle/PDL cells and osteoblasts throught out the root formation and eruption stages of tooth development. 2) RANKL expression became stronger at eruption stage than root formation stage of tooth development. 3) Strong expression of OPG was detected in follice/PDL cells of toot formation stage but it was decreased with tooth eruption. 2. Interdental separation between lower first and second molar 1) Comparared to normal animal, multinucleated osteoclasts and odontoclasts were markedly induced in the alveolar bone and tooth root with PDL remodeling in hematoxylin-eosin section. 2) PDLs22 expression was decreased with interdental separation. 3) RANKL expression was Increased with interdental separation in PDL fibroblasts, osteoblasts, odontoclasts and it lacunae, resorting dentin, cementum and bone matrix. 4) OPG expression was slightly decreased in the PDL cells adjacent to the alveolar bone and root surface with interdental separation. These results suggested that during tooth eruption and tooth movement, RANKL and OPG in the periodontal tissues are important determinants regulating balanced alveolar bone and tooth root resorption. And it is also suggested that PDL cells retained their characteristic phenotype during tooth eruption and interdental separation except for the short period of PDL remodeling.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.207-214
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• 2008

In Asia Saussurea lappa (SL) has been used as a traditional herbal medicine to treat abdominal pain and tenesmus. Recently, in vitro cell culture studies have shown that SL has anti-ulcer, anti-inflammatory, and anti-tumor properties. To explore its potential chemopreventive and chemotherapeutic effects in colon cancer, we examined whether the hexane extract of SL (HESL) could inhibit the growth of HT-29 human colon cancer cells, and investigated the mechanisms for this effect. The cells were cultured with various concentrations (0-5 ${\mu}g/mL$) of HESL. The results indicated that HESL markedly decreased the numbers of viable HT-29 cells; whereas at the concentration of 5 ${\mu}g/mL$, HESL slightly decreased the viable cell numbers of CCD 1108Sk human skin normal fibroblasts at 72 hr. HESL substantially increased the numbers of cells in the sub G1 phase, and dose-dependently increased apoptotic cell numbers. Western blot analysis of the total cell lysates revealed that HESL increased Bax protein levels, but did not affect Bcl-2 levels. HESL induced the cleavage of poly (ADP-ribose) polymerase and caspases 8, 9, 7, and 3. This study demonstrated that HESL inhibits cell growth and induces apoptosis in HT-29 cells, which may be mediated by its ability to increase Bax levels and activate the caspase pathway. These findings may lead to the development of new therapeutic strategies for colon cancer treatment.