• Microbiology and Biotechnology Letters
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• v.29 no.3
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• pp.181-185
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• 2001

The naturally occurring chemical indole-3-carbinol (13C), found in vegetables of the Brassica genus, is a promising anticancer agent that was shown previ- ously to induce a Gl cell cycle arrest of human breast cancer cell lines, independent of estrogen receptor signaling. The anticancer activity of 13C and the possible mechanisms of its action were explored in a human hepatocellular carcinoma cell line, HepG2. Treatment of HepG2 cells with 13C suppressed the growth of the cells. The growth sup- pression caused by 13C ($IC_{50}$/: 444$\mu$M) was found to be partially due to its ability to stop the cell cycle in HepG2 cells. Western blot analysis for the Gl phase artiest demonstrated that the expression-levels of cyclin-dependent kinase (Cdk4, Cdk6) and cyclic D were reduced strongly after treatment of Hep72 cells with 13C (4007M) for 24- 72 hrs. Furthermore, I3C selectively abolished the expression of Cdk6 in a dose- and time-dependent manner, and accordingly, inhibited the phosphorylation of retinoblastoma. Interestingly, after the HepG2 cells reached their max- imal growth arrest, the level of the p21, a well-known Cdk inhibitor, increased significantly. Therefore, it could be considered that the Gl arrest of HepG2 cells treated with 13C was due to the indirect inhibition of Cdk4/6 activities by p21 Western blot analysis for G2/M phase arrest of demonstrated the levels of Cdc2 and cyclin Bl werer reduced dramatically after the treatment of HepG2 cells with 13C ($40\mu$M) for 24-72 hrs. flow cytometry of propidium iodide-stained HepG2 cells revealed that 13C induces a Gl (53%,72hr incubation) and G2 (25%,24hr incubation) cell cycle arrest. Thus, our observations have uncovered a previously undefined antiproliferative pathway for r3C that implicates Cdk4/6 and Cdc2 as a target for cell cycle control in human HepG2 cells. However, the 13C-medi- ated cell cycle arrest and repression of Cdk4/6 production did not affect the apoptotic induction of HepG2 cell.

• Tuberculosis and Respiratory Diseases
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• v.65 no.6
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• pp.476-486
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• 2008

Background: TRAIL (TNF-related apoptosis inducing ligand) is a newly identified member of the TNF gene family which appears to have tumor-selective cytotoxicity due to the distinct decoy receptor system. TRAIL has direct access to caspase machinery and induces apoptosis regardless of p53 phenotype. Therefore, TRAIL has a therapeutic potential in lung cancer which frequently harbors p53 mutation in more than 50% of cases. However, it was shown that TRAIL also could activates $NF-{\kappa}B$ in some cell lines which might inhibit TRAIL-induced apoptosis. This study was designed to investigate whether TRAIL can activate $NF-{\kappa}B$ in lung cancer cell lines relatively resistant to TRAIL-induced apoptosis and inhibition of $NF-{\kappa}B$ activation using proteasome inhibitor MG132 which blocks $I{\kappa}B{\alpha}$ degradation can sensitize lung cancer cells to TRAIL-induced apoptosis. Methods: A549 (wt p53) and NCI-H1299 (null p53) lung cancer cells were used and cell viability test was done by MTT assay. Apoptosis was confirmed with Annexin V assay followed by FACS analysis. To study $NF-{\kappa}B$-dependent transcriptional activation, a luciferase reporter gene assay was used after making A549 and NCI-H1299 cells stably transfected with IgG ${\kappa}-NF-{\kappa}B$ luciferase construct. To investigate DNA binding of $NF-{\kappa}B$ activated by TRAIL, electromobility shift assay was used and supershift assay was done using anti-p65 antibody. Western blot was done for the study of $I{\kappa}B{\alpha}$ degradation. Results: A549 and NCI-H1299 cells were relatively resistant to TRAIL-induced apoptosis showing only 20~30% cell death even at the concentration 100 ng/ml, but MG132 ($3{\mu}M$) pre-treatment 1 hour prior to TRAIL addition greatly increased cell death more than 80%. Luciferase assay showed TRAIL-induced $NF-{\kappa}B$ transcriptional activity in both cell lines. Electromobility shift assay demonstrated DNA binding complex of $NF-{\kappa}B$ activated by TRAIL and supershift with p65 antibody. $I{\kappa}B{\alpha}$ degradation was proven by western blot. MG132 completely blocked both TRAIL-induced $NF-{\kappa}B$ dependent luciferase activity and DNA binding of $NF-{\kappa}B$. Conclusion: This results suggest that inhibition of $NF-{\kappa}B$ can be a potentially useful strategy to enhance TRAIL-induced tumor cell killing in lung cancer.

• Clinical and Experimental Pediatrics
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• v.46 no.1
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• pp.56-66
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• 2003

Purpose : Human umbilical vein endothelial cells(HUVECs) play an important role in regulating blood flow by releasing vasoactive substances. It has been reported that endothelial impairment and dysfunction might be a primary cause of placental vascular disease, which is manifested clinically as preeclampsia in mother and intrauterine growth restriction in fetus. Furthermore, the frequency of apoptotic changes is increased in umbilical and placental tissues from growth-restricted pregnancies. However, the various mechanisms of umbilical endothelial cell apoptosis have not been broadly proposed. We investigate the effects of amiloride derivatives on apoptotic death of HUVECs and identify their ionic mechanism. Methods : HUVECs were purchased from Clonetics, and cultured on endothelial cell growth medium. MTT assay and flow cytometry were used for assessing cytotoxic effect and confirming the apoptosis. Changes in intracellular ion concentrations were measured with specific fluorescent dyes and fluorescence imaging analysis system. Results : Amiloride derivatives elicited cytotoxic effects on HUVECs with dose-dependent manners and the rank order of potency is HMA($IC_{50}\;11.2{\mu}M$), MIA>EIPA>>amiloride. HMA-induced cytotoxicity is dependent on extra- and intracellular pH, that is, increase extra- and intracellular pH augmented the cytotoxic effects of HMA. HMA dose-dependently reduced intracellular major ions, such as $K^+$ and $Cl^-$. Interestingly, the depletion of intracellular ions induced by HMA was also significantly enhanced at alkaline extracellular pH. Conclusion : Amiloride derivatives induce apoptosis of HUVECs with dose and pH dependent manners. They reduce intracellular $K^+$ and $Cl^-$ concentration, which is also extracellular pH dependent.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.3
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• pp.217-229
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• 2010

Objective: Apoptosis plays an important role for the maintenance of the normal pregnancy. Expression of X-linked inhibitor of apoptosis (XIAP) is able to effectively prevent apoptosis and controls trophoblast cells death throughout placental development, but it is still unknown in the function of XIAP in trophoblast cells exposed to hypoxic condition, which is one of the factors causing preeclampsia. Therefore, we conducted to compare XIAP expression in normal and pre-eclamptic placenta tissues and analyzed the function of XIAP in HTR-8/SVneo trophoblast cell line exposed to hypoxic condition. Methods: The expression of XIAP was analyzed in placental tissues from the following groups of patients (none underwent labor): 1) term normal placenta (n=15); 2) term with pre-eclamptic placeneta (n=15); and 3) pre-term with pre-eclamptic placenta (n=11) using semi-quantitative RT-PCR, immunohistochemistry, and Western blot. In order to evaluate the function of XIAP in HTR-8/SVneo trophoblast cells under hypoxic condition, HIF-$1{\alpha}$ plasmids, and hypoxic condtion were transfected and treated into HTR-8/SVneo trophoblast cells for 24 hours, respectively. Results: We observed that XIAP are expressed in the syncytiotrophoblasts and syncytial knot of placental villi. The expression of XIAP was significantly decreased in preeclamptic placenta tissues than in normal placenta tissues without labor (p<0.05). Furthermore, we confirmed the XIAP expression in HTR-8/SVneo trophbolast cells exposed to hypoxia was translocated from cytoplasm into nucleus and decreased XIAP by hypoxic condition induced apoptosis in HTR-8/SVneo trophoblast cells through up-regulation of pro-apoptotic proteins. Conclusion: These results suggest that the expression of XIAP is involved in placental development as well as decreased expression of XIAP by hypoxia is associated with pre-eclampsia through inducing trophoblast cells apoptosis.

• Korean Journal of Food Science and Technology
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• v.53 no.3
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• pp.267-277
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• 2021

To evaluate hepatoprotective effects, the antioxidant capacities of matcha green tea extract (Camellia sinenesis) were compared to those of green leaf tea and the anti-inflammatory activities in HepG2 cells were investigated. Evaluation of the total phenolic and total flavonoid content, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, and inhibitory effect on lipid peroxidation indicated that the aqueous extract of matcha green tea presented significant catechin content and antioxidant capacity compared to those of green leaf tea. In addition, the extract had considerable inhibitory effects on α-glucosidase, α-amylase, and advanced glycation end-products. The matcha green tea extract significantly increased cell viability and reduced reactive oxygen species in H₂O₂- and high-glucose-treated HepG2 cells. Furthermore, in response to oleic acid-induced HepG2 cell injury, treatment with matcha green tea aqueous extract inhibited lipid accumulation and regulated the expression of inflammatory proteins such as p-JNK, p-Akt, p-GSK-3β, caspase-3, COX-2, iNOS, and TNF-α. Matcha green tea could be used as a functional material to ameliorate hepatic lipid accumulation and inflammation.

• Journal of Veterinary Clinics
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• v.27 no.5
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• pp.546-552
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• 2010

Previous studies could not offer available guideline to decide size of balloon and grade of injury before induction of spinal cord injury (SCI) because grade of SCI was assessed after inserting a catheter and each experimental animal were different in body size and weight as well as in species. This study was performed to provide guideline for standardized SCI model. Eight healthy adult beagle dogs that had 8 mm of spinal canal height were assigned to four groups according to the diameter of balloon and compression time: 4 mm/3hrs, 4 mm/6hrs, 4 mm/12hrs and 6 mm/3hrs group. Radiography was performed to standardize between experimental animal and balloon before selecting balloon diameter to induce SCI. Behaviors outcomes, somatosensory evoked potentials (SEPs), magnetic resonance imaging (MRI) and histopathological examination were evaluated. Behaviors outcomes and SEPs were not available to assess grade of SCI and those only indicate SCI. The damaged area was revealed clear hyperintensity on STIR image and T2WI after induction of SCI. The hyperintense area on MRI was cranially and caudally expanded with increasing of the diameter of balloon or the compression time. Well corresponded to expanding of hyperintense area on MRI, the damaged region and the numbers of caspase-3 and PARP immunoreactive cells were increased on histopathological findings. Therefore, these results will be considered fundamental data to induce standardized SCI model in experimental animal that has various weight and size.

• Korean Journal of Food Science and Technology
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• v.51 no.4
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• pp.379-392
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• 2019

The current study investigated the effect of Gabjubaekmok (Diospyros kaki) ethanolic extract (GEE) on $H_2O_2$-induced human neuroblastoma MC-IXC cells and amyloid beta $(A{\beta})_{1-42}$-induced ICR (Institute of Cancer Research) mice. GEE showed significant antioxidant activity that was evaluated based on ABTS, DPPH scavenging activity, and inhibition of malondialdehyde (MDA) and acetylcholinesterase activity. Further, GEE inhibited ROS production and increased cell viability in $H_2O_2$-induced MC-IXC cells. Administration of GEE ameliorated the cognitive dysfunction on $A{\beta}$-induced ICR mice as evaluated using Y-maze, passive avoidance, and Morris water maze tests. Results of ex vivo test using brain tissues showed that, GEE protected the cholinergic system and mitochondrial functions by increasing the levels of antioxidants such as ROS, mitochondrial membrane potential (MMP), and adenosine triphosphate (ATP) against $A{\beta}$-induced cognitive dysfunction. Moreover, GEE decreasd the expression levels of apoptosis-related proteins such as $TNF-{\alpha}$, p-JNK, p-tau, BAX and caspase 3. While, expression levels of p-Akt and $p-GSK3{\beta}$ increased than $A{\beta}$ group. Finally, gallic acid was identified as the main compound of GEE using high performance liquid chromatography.

• Journal of Apiculture
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• v.34 no.3
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• pp.245-254
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• 2019

We investigated the anti-tumor effects and molecular mechanism of Brazil, China and Korean regional propolis on HeLa ovarian cancer cell line. Each propolis extracts was prepared by ethanol extraction method. Cytotoxicity of propolis extracts was determinated by EZ-cytox cell viability assay. To necessity of anti-tumor effect and molecular mechanism of propolis, we must be adjusting propolis concentration. Due to 100 ㎍/mL of propolis extract were reduced cell viability to less than 50%, we adjusted all of propolis concentration to 100 ㎍/mL. By Western blotting analysis, we confirmed that anti-tumor mechanism of Brazil, China and Korea regional propolis has significantly difference. All of propolis was activated apoptosis related molecules such as PARP, caspase-3. However, cell proliferation signaling molecules including Akt1, ERK and Bcl-2 were reduced the protein expression level. Especially, the expression of tumor suppressor protein p53 was significantly increased in propolis-treated group such as Gyeonggi, Chungbuk, Chungnam, Jeonbuk, Gyeongnam and China. The phosphorylation of Bax which as apoptosis indicator was appeared in propolis-treated group such as Gyeonggi, Gangwon, Chungnam, Gyeongbuk, China. In this results showed that the regional propolis has completely different mechanism in anti-tumor. Thus, propolis extracts may be useful source of functional materials on anti-cancer and it will be able to choose the suitable propolis for cancer therapy by analyzing individual characteristics.