• Biomedical Science Letters
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• v.17 no.1
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• pp.69-77
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• 2011

In this study, we evaluated the protective effects of supercritical extracts and two step ethanol extracts after supercritical extraction from Schizandra chinensis on antioxidant activities and oxidative DNA and cell damages. Supercritical extracts removed DPPH (1,1-diphenyl-2-picryldrazyl) radical by 85.5% at 200 ${\mu}g$/ml, but showed low activities of scavenging and chelating the hydroxyl radical and ferrous iron. However, two step ethanol extracts showed low activities of scavenging the DPPH radical, but removed the hydroxyl radical by 86% at 200 ${\mu}g$/ml. In addition, we tested the activities of extracts for reducing hydroxyl radical-induced DNA and cell damage. Two step ethanol extracts showed protective effect against the oxidative DNA damage by reducing DNA segmentation, inhibiting DNA migration and decreasing the expression of phospho-H2AX. Also, two step ethanol extracts showed protective effect against the oxidative cell damage by inhibiting lipid peroxidation and increasing the expression of p21 protein. Taken together, we suggest that two step ethanol extracts from S. chinensis have a role as useful inhibitors against oxidative damages.

• BMB Reports
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• v.41 no.12
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• pp.833-839
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• 2008

Angiogenesis in tumors is driven by multiple growth factors that activate receptor tyrosine kinases. An important driving force of angiogenesis in solid tumors is signaling through vascular endothelial growth factor (VEGF) and its receptors (VEGFRs). Angiogenesis inhibitors that target this signaling pathway are now in widespread use for the treatment of cancer. However, when used alone, inhibitors of VEGF/VEGFR signaling do not destroy all blood vessels in tumors and do not slow the growth of most human cancers. VEGF/VEGFR signaling inhibitors are, therefore, used in combination with chemotherapeutic agents or radiation therapy. Additional targets for inhibiting angiogenesis would be useful for more efficacious treatment of cancer. One promising target is the signaling pathway of hepatocyte growth factor (HGF) and its receptor (HGFR, also known as c-Met), which plays important roles in angiogenesis and tumor growth. Inhibitors of this signaling pathway have been shown to inhibit angiogenesis in multiple in vitro and in vivo models. The HGF/c-Met signaling pathway is now recognized as a promising target in cancer by inhibiting angiogenesis, tumor growth, invasion, and metastasis.

• YAKHAK HOEJI
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• v.56 no.4
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• pp.248-253
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• 2012

This study aims to develop a novel regimen for enhanced efficacy and reduced side effect in inhibiting platelet aggregation and blood coagulation by concurrent administration of triflusal and ibudilast as anticoaggulants. The result shows this combination of triflusal and ibudilast (300~500 ${\mu}M$, respectively) has additive effect in inhibiting platelet aggregation and blood coagulation over the administration of truflusal or ibdilast as a single treatment. This pharmaceutical composition is expected to be useful for the prevention or treatment of various diseases and symptoms, for example, ischemic heart disease, ischemic cerebral infarction, arteriosclerosis, and thrombosis caused by the insertion of a stent.

• YAKHAK HOEJI
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• v.43 no.6
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• pp.756-761
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• 1999

Lipid peroxidation mediated by hydroxyl radicals which are generated during myocardial ischermia has suggested as a possible mechanism of ischemic myocardial damage. Recently, it has been reported that anti-arrhythmic action of lidocaine, a local anesthetic, is attributed to its "membrane-stabilizing" properties through scavenging free radicals, thus, inhibiting lipid peroxidation. Aldehyde oxidase and xanthine oxidase which catalyze the oxidation of many purine, pyrimidine and pteridine derivatives are known as free radical generating systems. In this experiment, we studied the effect of lidocaine and procainamide on the hepatic aldehyde and xanthine oxidase activity and antioxidative activities. It was found that lidocaine and procainamide inhibited both NADPH-dependent and independent lipid peroxidation. Both of tested compounds were found to be ineffective in inhibiting xanthine oxidase. Lidocaine and procainamide, however, inhibited aldehyde oxidase activity in vitro as well as in vivo. Based on the above results, lidocaine and procainamide could be employed as a therapeutic agent for aldehyde oxidaserelated disease.d disease.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.755-760
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• 2009

The growth-inhibiting activities of persimmon roots-derived materials against intestinal bacteria were evaluated and compared with that of 1,4-naphthoquinone as a positive control. The active constituent isolated from persimmon roots was characterized as 5-hydroxy-2-methyl-1,4-naphthoquinone using various spectroscopic analyses. Treatment with 1,4-naphthoquinone at a dose of 1.0 mg/disc strongly inhibited the growth of 6 intestinal bacteria. Furthermore, when the structure-activity relationships of 1,4-naphthoquinone's derivatives were evaluated, 5-hydroxy-2-methyl-1,4-naphthoquinone and 2-methyl-1,4-naphthoquinone were found to strongly inhibit the growth of Clostridium difficile, Clostridium perfringens, and Escherichia coli without adversely affecting the growth of Bifidobacterium adolescentis, Bifidobacterium longum, and Lactobacillus acidophilus. Additionally, 2-hydroxy-1,4-naphthoquinone and 5-hydroxy-1,4-naphthoquinone strongly inhibited the growth of C. difficile and C. perfringens, but did not inhibit the growth of E. coli. Taken together, these results indicate that persimmon roots-derived materials and some of 1,4-naphthoquinone's derivatives could be useful preventive agents against diseases caused by harmful intestinal bacteria.

• Molecules and Cells
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• v.41 no.2
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• pp.103-109
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• 2018

Calcium ions are involved in the regulation of diverse cellular processes. Fourteen genes encoding calcium binding proteins have been identified in Dictyostelium. CBP7, one of the 14 CBPs, is composed of 169 amino acids and contains four EF-hand motifs. Here, we investigated the roles of CBP7 in the development and cell migration of Dictyostelium cells and found that high levels of CBP7 exerted a negative effect on cells aggregation during development, possibly by inhibiting chemoattractant-directed cell migration. While cells lacking CBP7 exhibited normal development and chemotaxis similar that of wild-type cells, CBP7 overexpressing cells completely lost their chemotactic abilities to move toward increasing cAMP concentrations. This resulted in inhibition of cellular aggregation, a process required for forming multicellular organisms during development. Low levels of cytosolic free calcium were observed in CBP7 overexpressing cells, which was likely the underlying cause of their lack of chemotaxis. Our results demonstrate that CBP7 plays an important role in cell spreading and cell-substrate adhesion. cbp7 null cells showed decreased cell size and cell-substrate adhesion. The present study contributes to further understanding the role of calcium signaling in regulation of cell migration and development.

• KSBB Journal
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• v.18 no.1
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• pp.45-50
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• 2003

In this study, the optimum conditions for mycelium culture of the mushroom Tricholoma matsutake and the inhibitory effect of the mycelium extracts no tyrosinase activity have been examined. When the extracts of the Tricholoma matsutake mycelia were tested for inhibitory activity on tyrosinase, it was found that the components extracted with ethyl acetate and water showed the highest inhibitory activity. The effect of antioxidants on the growth of mycelium and tyrosinase-inhibiting activity was also investigated. The results showed that tocopherol inhibited the growth in a concentration-dependent manner. In terms of tyrosinase-inhibiting activity, however, tocopherol was found to enhance the inhibitory activity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.1
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• pp.67-70
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• 2013

This research study was to develop methods for inhibiting the germination of cotton seeds. Germination rates after heating treatment at $80^{\circ}C$ with 10, 20, 30, 40 min. were 9.3, 9.3, 5.3 and 1.3 percentage, respectively. Heat treatment over $85^{\circ}C$ with 10 min. caused no germination of cotton seeds. Germination was significantly reduced with gamma rays treatment more than 10,000 gy, while the treatment within 2,000-8,000 gy induced less effects. Microwave processing for 30 seconds and 60 seconds inhibit the germination of cotton seed under 8 and 0%, respectively. As a physical treatment, rollmill milling with 1.5, 2, 2.5 mm gap inhibited any germination of cotton seeds. The optimum gap of roll-mill for processing physical cracking was below 51% of the thickness of seed.

• Journal of Applied Biological Chemistry
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• v.43 no.1
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• pp.54-58
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• 2000

Methanol extracts of 27 Brazilian plant samples and 10 oriental medicinal plant samples (27 families), using spectrophotometric and paper disc agar diffusion methods under anaerobic conditions, were tested in vitro for their growth-inhibiting activities against Bifidobacterium longum, Bifidobacterium bifidum, Bifidobacterium adolescentis, Clostridium perfringens, and Bacteroides fragilis. The responses varied with bacterial strains, plant species, and tissues sampled. In a test with B. longum and B. bifidum(20 mg/disc), extracts of Acanthopanax sessilifolinus stem bark and Ampelozizyphus amazonicus leaves strongly inhibited the growth of B. longum, whereas other plant samples did not inhibit any intestinal bacteria tested. At 5 mg/disc, adding extracts of Aralia eleta, Euterpe oleracea, and Syzygium guineense to the media strongly inhibited the growth of C. perfringens and B. fragilis without growth inhibition of B. adolescentis, B. longum, and B. bifidum. Extracts of Jacaranda mimosifolia and Ulmus paraifolia significantly inhibited the growth of C. perfringens and B. fragilis as well as B. adolescentis. These results may be indications of at least one of the pharmacological actions of the five Brazilian plants but not oriental medicinal plants tested.

• Korean Journal of Microbiology
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• v.29 no.4
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• pp.250-257
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• 1991

An obligate methanol-oxidizing bacterium, Methylobacillus sp. strain SK1, which grows only on methanol was isolated from soil. The isolate was nonmotile Gram-negtive rod. It does not have internal membrane system. The colonies were small, whitish-yellow, and smooth. The guanine plus cytosine content of the DNA was 48 mol%. Cellular fatty acids consisted predominantly of large amounts of straight-chain saturated $C_{16:0}$ acid and unsaturated $C_{16:1}$ acid. The major ubiquinone was Q-8, and Q-10 was present as minor component. The cell was obligately aerobic and exhibited catalase, but no oxidase, activity. Poly-.betha.-hydroxybutyrate, endospores, or cysts were not observed. the isolate could grow only on methanol in mineral medium. Growth factors were not required. The isolate was unable to use methane, formaldehyde, formate, methylamine, and several other organic compounds tested as a sole source of carbon and energy. Growth was optimal at 35.deg.C and pH 7.5. It could not grow at 42.deg.C. The doubling time was 1.2h at 30.deg.C when grown with 1.0%(v/v) methanol. The growth was not affected by antibiotics inhibiting cell wall synthesis and carbon monoxide but was completely suppressed by those inhibiting protein synthesis. Methanol was found to be assimilated through the ribulose monophosphate pathway. Cytochromes of b-, c-, and o- types were found. Cell-free extracts contained a phenazine methosulfate-linked methanol dehydrogenase activity, which required ammonium ions as an activator. Cells harvested after the late exponential phase seemed to contain blue protein.ein.