• 미생물학회지
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• 제50권1호
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• pp.22-26
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• 2014

Protocatechualdehyde (PA)는 항산화 활성과 항암 활성을 가진 페놀성 물질이다. Streptomyces lincolnensis M-20 균주에서 생산된 PA를 균주 상등액에서 분리, 정제하였다. 항산화 활성을 가진 PA가 구리 이온 존재 하에서는 산화촉진제로 작용하였다. 항산화 활성은 DPPH를 이용한 방법으로 측정하였으며, 구리 이온 존재 하에서 PA의 산화 촉진 작용은 pBR322 플라스미드의 DNA 절단 작용으로 측정하였다. DNA 손상으로 생성되는 활성산소 종의 확인은 활성 산소종의 포집자인 글루타치온에 의해 DNA 절단이 억제되는 것으로 확인하였다. PA와 구리 이온의 복합체 형성은 금속 이온의 킬레이트인 EDTA가 존재할 경우와 존재하지 않을 경우를 자외선/가시광선 분광학적 분석법으로 비교, 확인하였다.

• Journal of Microbiology and Biotechnology
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• 제28권10호
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• pp.1645-1653
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• 2018

The genus Acer contains several species with various bioactivities including antioxidant, antitumor and anti-inflammatory properties. However, Acer okamotoanum Nakai, one species within this genus has not been fully studied yet. Therefore, in this study, we investigated the anti-adipogenic activities of leaf extract from A. okamotoanum Nakai (LEAO) on 3T3-L1 preadipocytes. Adipogenesis is one of the cell differentiation processes, which converts preadipocytes into mature adipocytes. Nowadays, inhibition of adipogenesis is considered as an effective strategy in the field of anti-obesity research. In this study, we observed that LEAO decreased the accumulation of lipid droplets during adipogenesis and down-regulated the expression of key adipogenic transcription factors such as peroxisome proliferator-activated receptor ${\gamma}$ (PPAR ${\gamma}$) and CCAAT/enhancer binding protein ${\alpha}$ (C/EBP ${\alpha}$). In addition, LEAO inactivated PI3K/Akt signaling and its downstream factors that promote adipogenesis by inducing the expression of PPAR ${\gamma}$. LEAO also activated ${\beta}$-catenin signaling, which prevents the adipogenic program by suppressing the expression of PPAR ${\gamma}$. Therefore, we found that treatment with LEAO is effective for attenuating adipogenesis in 3T3-L1 cells. Consequently, these findings suggest that LEAO has the potential to be used as a therapeutic agent for preventing obesity.

• 한국발생생물학회지:발생과생식
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• 제22권2호
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• pp.133-142
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• 2018

Patients with type II diabetes mellitus are more susceptible to colorectal cancer (CRC) incidence than non-diabetics. The anti-diabetic drug metformin is most commonly prescribed for the treatment of this disease and has recently shown antitumor effect in preclinical studies. The aberrant mutational activation in the components of RAS/RAF/MEK/ERK and PI3K/AKT/mTOR signaling pathway is very frequently observed in CRC. We previously reported that metformin inhibits the phosphorylation of ERK and BEZ235, a dual inhibitor of PI3K and mTOR, has anti-tumor activity against HCT15 CRC cells harboring mutations of KRAS and PIK3CA. Therefore, we hypothesized that simultaneous inhibition of two pathways by combining metformin with BEZ235 could be more effective in the suppression of proliferation than single agent treatment in HCT15 CRC cells. Here, we investigated the combinatory effect of metformin and BEZ235 on the cell survival in HCT15 CRC cells. Our study shows that both of the two signaling pathways can be blocked by this combinational strategy: metformin suppressed both pathways by inhibiting the phosphorylation of ERK, 4E-BP1 and S6, and BEZ235 suppressed PI3K/AKT/mTOR pathway by reducing the phosphorylation of 4E-BP1 and S6. This combination treatment synergistically reduced cell viability. The combination index (CI) values ranged from 0.44 to 0.88, indicating synergism for the combination. These results offer a preclinical rationale for the potential therapeutic option for the treatment of CRC.

• 동의생리병리학회지
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• 제19권3호
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• pp.802-810
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• 2005

The tetrahydroisoquinolines included potent cytotoxic agents that showed antitumor activity,antimicrobial activity, and other biological properties. We studied the effect of CDST, 1-Chloromethyl-6,7-dimethoxy-3,4-dihydro-1H-isoquinoline-2-sulfonic acid amide, a newly synthesized anti-cancer agent. The cytotoxic activity of CDST in HL-60 cells was increased in a dose-dependent manner. CDST, tetrahydroisoquinolines derivative, was cytotoxic to HL-60 cells, with IC50 of $80{\mu}g/ml$. Treatment of CDST to HL-60 cells showed the fragmentation of DNA in a dose- and time dependent manner, suggesting that thesecells underwent apoptosis. Treatment of HL-60 cells with CDST was induced in a dose- and time-dependent activation of caspase-3, caspase-8 and proteolytic cleavage of poly(ADP-ribose) polymerase. In caspase activity assay, caspase-3 and -8 was activated after 12 h and 6 h posttreatment, respectively. CDST also caused the release of cytochrome c from mitochondria into the cytosol. CDST-induced cytochrome c release was mediated by caspase-8-dependent cleavage of Bid and Bax translocation. These results suggest that caspase-8 induced Bid cleavage and Bax translocation, caused mitochondrial cytochrome c release, and induce caspase-3 activationduring CDST-induced apoptosis in HL-60 cells.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1993년도 제2회 신약개발 연구발표회 초록집
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• pp.71-71
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• 1993

Carboxylesterase is widely distributed in the tissues of vertebrates, insects, plants and mycobacteria. Among various tissues of animals and humans, the highest esterase activity with various substrates is found in the liver. Kidney has moderate carboxylesterase activity in the proximal tubules. Considerable esterase activity is also found in the small intestine epithet elial cells and serum of mammals. Besides these tissues, carboxylesterase has been found in the lung, testis, adipose tissue, nasal mucosa and even in the central nervous system. Hepatic microsomal carboxylesterase catalyzes the hydrolysis of a wide variety of endogenous and exogenous compounds such as carboxylester, thioester and aromatic amide. Since carboxylesterases are important for metabolic activation of prodrugs and detoxification of xenobiotics, differences in substrate specificity and immunological properties of this enzyme are important in connection with choosing a suitable laboratory animal for the evaluation of biotransformation and toxicity of drugs. On the other hand, liver, kidney, intestine and serum were found to contain multiple forms of carboxylesterases in animal species and humans. In fact, we have purified more than fifteen isoforms of carboxylesterases from microsomes of liver, kidney and intestinal mucosa of nine animal species and humans. and characteristics of these isoforms were compared each other in terms of their physical and immunochemical properties. On the other hand, we have reported that hepatic microsomal carboxylesterases are induced by many exogenous compounds such as phenobarbital, polycyclic aromatic hydrocarbons, Aroclor 1254, aminopyrine and clofibrate. Later, we showed that some isoforms of hepatic carboxylesterase were induced by glucocorticoids such as dexamethasone and 16 ${\alpha}$-carbonitrile, but other isoforms were rather inhibited by these compounds. These findings indicate that involvement of carboxylesterases in the metabolism and toxicity of drugs should be explained by the isoforms involved. Since 1991, we have carried out detailed research investigating the types of carboxylesterases involved in the metabolic activation of CPT-11, a derivative of camptothecin, to the active metabolite, SN-38. The results obtained strongly suggest that some isoforms of carboxylesterase of liver microsomes and intestinal mucosal membrane are exclusively involved in CPT-11 metabolism. In this symposium, the properties of carboxylesterase isoforms purified from liver, kidney and intestine of animal species and humans are outlined. In addition, metabolism of CPT-11, a novel antitumor agent, by carboxylesterases in relation to the effectiveness will also be discussed.

• Biomolecules & Therapeutics
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• 제5권4호
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• pp.369-375
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• 1997

General pharmacological effects of SB-31$^{R}$, the extracts of Pulsatilla koreana, were investigated in mice, rats and guinea-pigs. Intravenous injection of SB-31 (3 and 6 ml/kg) produced almost no effect on central nervous system no effects on the general symptom and behaviors of mice, spontaneous locomotor activity, pentobarbital- induced sleeping time , rotared performance , electroshock and pentylenetertrazole -induced seizures, acetic acid-induced writhing and normal body temperature in mice. SB-31 showed little effects on the spontaneous movement of the isolated ileum and contraction induced by agonists in isolated ileum, suggesting no influence on autonomic nervous system. Administration of SB-31 also did not show any effect on blood pressure in conscious rats. However, a slight decrease in heart rate was observed at high doses (6 and 10 ml/kg) of SB-31 in conscious rats. Similarly, a slight increase in respiratory rate was observed at 6 m1/kg of SB-31 in anesthetized rats. SB-31 did not produce any effect at the dose of 3 ml/kg, but showed a tendency to increase the urinary volume at 6 ml/kg, and produced a decrease in urinary excretions of N $a_{+}$and $K_{+}$at 6 ml/kg. However, transport capacity within the gastrointestinal tract and the secretion of the gastric juice were not influenced by 6 ml/kg of SB-31. In conclusion, these results suggest that SB-31 did not pro-duce any acute effects on the central nervous system, autonomic nervous system, respiratory and circulatory systems, digestive system and kidney function at the dose of below 3 ml/kg.ml/kg.

• 한국식품위생안전성학회지
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• 제13권2호
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• pp.94-98
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• 1998

항암 효과가 뛰어난 건강식품으로 알려진 아가리쿠스 버섯은 많은 약리 성분을 함유하고 잇는 것으로 알려져 있다. 아가리쿠스 버섯의 주요성분을 동정하기 위하여 우선 일반성분을 분석하고 그것을 약리성분 분석의 기초 자료로 이용하고자 하였다. 건조 아가리쿠스 버섯의 일반성분은 일본산 아가리쿠스 버섯과 큰 차이는 없었으나, 당질의 함량이 일본산이 41.56% 인 반면 , 한국산 5.40%로 매우 낮게 나타났다. 무기물의 조성은 일본산 K, Phosphate, Si, Chloride 그리고 Mg 이 각각 56.49%, 12.7%, 12.25%, 4.26%, 2.67%의 순으로 나타나 있는데 반해, 본 실험에서 사용한 한국산 아가리쿠스 버섯의 무기물 조성 함량은 K, Phosphate, Si, Chloride 그리고 Sulfate가 각각 45.77%, 27.78%, 8.16%, 7.80%의 순으로 나타났다. 아미노산은 cysteine을 제외한 16종의 아미노산이 모두 존재하는 것으로 나타났으며, 아미노산중 glutamic acid 가 19.33%로 가장 많이 함유된 것으로 나타났다. 지방산은 linoleic acid가 78.3%로 지방산의 대부분을 이루고 있는 것으로 나타났으며, 그 중 불포화 지방사의 함량은 일본산 아가리쿠스 버섯이 70.5%인데 반해, 한국산 아가리쿠스 버섯의 함량은 80.7%로 일본산 아가리쿠스 버섯보다 다소 높게 나타났다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 1999년도 The 6th International Symposium on the Development of Anti-Cancer Resource from Plants
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• pp.1-45
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• 1999

To date many kinds of compounds have been obtained from plants kingdom as antineoplastic and anti-cancerous agents. However, there is no special type of compounds for ncancer therapy. Various types of substances are effective for various types of cancers and tumors: for instance, alkaloids, lignans, terpenes and steroids etc. Curcumol obtained from Curcuma aromatica was tested and noticed to be effective against cancer of the uterine cervix clinically Oridonin isolated from Rabdosia ssp.is now investigated for clinical trials in China. Moreover, camptothecine isolated from Camptotheca acuminata is also antineoplastic alkaloid, but is very toxic. Chemical modification has been tried to decrease its toxicity. This compound is now using as clinical agent. Harringtonin was investigated as an anticancerous drug in China. Taxol, a compound with a taxane ring isolated from the bark of Taxus brevifolia, has been demonstrated to have substantial anticancer activity in patients with solid tumors refractory standard chemotherapy. Supply of this drug has severely limited full exploration of its antineoplastic potential. Some efforts are continued in National Cancer Institute NCI) Washington for surveying various Taxus species for optimal taxol content, improvement in semi-synthesis from baccatin III, improvement in method of extraction, and development of alternative renewable resources. Further, there are many compounds which have been reported as antineoplastic agents. On the other hand, we have screened on higher plants collected in Japan, China, Korea, Southeast Asia and South America for antineoplastic activity, which has been done using Sarcoma 180 ascites in mice, P388 Iymphocytic leukemia in mice, Chinese hamster lung V-79 cells, P388 cells and nasopharynx carcinoma (KB) cells in our laboratory, as primary screening. In this meeting, I will present on antitumor and cytotoxic substances of the higher plants (Rubia cordifolia, Ailanfhus Vilmoriniana, Aster tataricus, Taxus cuspidata var. nana, Cephalotaxus harringtonia var drupacea, etc.) selected from above screening tests.

• 한국약용작물학회지
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• 제19권4호
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• pp.287-299
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• 2011

Pharmacological effects of Panax ginseng have been demonstrated in cardiovascular system, endocrine secretion and immune system, together with antitumor, anti-stress and anti-oxidant activities. Modern scientific data show protective effect of ginseng against bone marrow cell death, increased survival rate of experimental animals, recovery of hematopoietic injury, immunopotentiation, reduction of damaged intestinal epithelial cells, inhibition of mutagenesis and effective protection against testicular damages, caused by radiation exposure. And also, ginseng acts in indirect fashion to protect radical processes by inhibition of initiation of free radical processes and thus reduces the radiation damages. The research has made much progress, but still insufficient to fully uncover the action mechanism of ginseng components on the molecule level. This review provides the usefulness of natural product, showing no toxic effects, as an radioprotective agent. Furthermore, the further clinical trials on radioprotection of ginseng need to be highly done to clarify its scientific application. The effective components of ginseng has been known as ginsenosides. Considering that each of these ginsenosides has pharmacological effect, it seems likely that non-saponin components might have radioprotective effects superior to those of ginsenosides, suggesting its active ingredients to be non-saponin series. These results also show that the combined effects of saponin and non-saponin components play an important role in the radioprotective effects of ginseng.

• Journal of Microbiology
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• 제45권3호
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• pp.187-192
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• 2007

REOviruses (Respiratory Enteric Orphan viruses) are ubiquitous, non-enveloped viruses containing 10 segments of double-stranded RNA (dsRNA) as their genome. They are common isolates of the respiratory and gastrointestinal tract of humans but are not associated with severe disease and are therefore considered relatively benign. An intriguing characteristic of reovirus is its innate oncolytic potential, which is linked to the transformed state of the cell. When immortalized cells are transfected in vitro with activated oncogenes such as Ras, Sos, v-erbB, or c-myc, they became susceptible to reovirus infection and subsequent cellular lysis, indicating that oncogene signaling pathways are exploited by reovirus. This observation has led to the use of the virus in clinical trials as an anti-cancer agent against oncogenic tumors. In addition to the exploitation of oncogene signaling, reovirus may further utilize host immune responses to enhance its antitumor activity in vivo due to its innate interferon induction ability. Reovirus is, however, not entirely benign to immunocompromised animal models. Reovirus causes so-called "black feet syndrome" in immunodeficient mice and can also harm neonatal animals. Because cancer patients often undergo immunosuppression due to heavy chemo/radiation-treatments or advanced tumor progression, this pathogenic response may be a hurdle in virus-based anticancer therapies. However, a genetically attenuated reovirus variant derived from persistent reovirus infection of cells in vitro is able to exert potent anti-tumor activity with significantly reduced viral pathogenesis in immunocompromised animals. Importantly, in this instance the attenuated, reovirus maintains its oncolytic potential while significantly reducing viral pathogenesis in vivo.