• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.575-580
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• 2017

This study analyzed the effects of RGG box of hnRNP A1 on its subcellular localization and stabilization of hnRNP A1 over a three year period from October 2014. First, a 6R/K mutation in RGG box was generated, and pcDNA1-HA-hnRNP A1(6R/K) was constructed. The subcellular localization of hnRNP A1(6R/K) from the HeLa cells transfected with this plasmid DNA was analyzed by immunofluorescence microscopy. HA-hnRNP A1(6R/K) was found to exhibit nuclear and cytoplasmic fluorescence. The stability of hnRNP A1(6R/K) was checked by Western blot analysis using the expressed protein from the HeLa cells transfected with the pcDNA1-HA-hnRNP A1(6R/K). The results show that HA-hnRNP A1(6R/K) has a smaller size. These confirm that HA-hnRNP A1(6R/K) is localized both in the nuclear and cytoplasm, not because 6R/K mutation affects the nuclear localization of hnRNP A1, but because 6R/K mutation causes hnRNP A1(6R/K) to cleave at the mutation or near the mutation site. The cleaved protein fragment, which lacks the M9 domain (i.e. nuclear localization signal of hnRNP A1), did not exhibit nuclear fluorescence. This suggests that the arginines of RGG box in hnRNP A1 play an important role in stabilizing hnRNP A1. An analysis of the RNA-binding ability of hnRNP A1(6R/K) expressed and purified from bacteria will be a subsequent research project.

• Journal of Plant Biotechnology
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• v.35 no.4
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• pp.291-298
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• 2008

Methylmercury, an organic derivative, is the principal form of mercury that biomagnifies and causes neurodegenerative symptoms in animals. In recent years, living modified organism (LMO) resulting from biotechnology has played a highly visible and controversial role. Despite the potential benefits of this technology, public concerns have been raised about the environmental risk of LMO. The concern on the risk from LMO release has urged efforts to evaluate and manage the risks of the LMO. To build up the capacity building of risk assessment method for LMO used environmental remediation, we engineered Solanum nigrum L, expressing the modified bacterial gene, merB, encoding organomercurial lyase. Two independently isolated transgenic lines produced merB RNA. Transgenic Solanum nigrum leaf discs expressing merB gene showed organic mercury resistance, forming shoots well on growth medium containing $0.5{\mu}M$ methylmercury (II) chloride and $1{\mu}M$ phenylmercuric acetate while control plants breached. Transgenic merB seeds germinated and grew on growth medium containing $2{\mu}M$ methylmercury (II) chloride and phenylmercuric acetate. The merB transgenic plants will be used for risk assessment of natural environment.

• Journal of Life Science
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• v.19 no.1
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• pp.1-8
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• 2009

In this paper, to elucidate the further mechanisms of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced growth arrest, we investigated the effect of MNNG on cell cycle and proliferation in U937 cells, a p53-null human myeloid leukemia cell line. It was found that MNNG causes an arrest at the G2/M phase of the cell cycle and induces apoptosis, which is closely correlated to inhibition of cyclin B1 and cyelin-dependent kinase (Cdk) 2-associated kinase activities. MNNG treatment in. creased protein and mRNA levels of the Cdk inhibitor p21(WAF1/CIP1), and activated the reporter construct of a p21 promoter. By using p21 promoter deletion constructs, the MNNG-responsive element was mapped to a region between 113 and 61 relative to the transcription start site. These data indicate that in U937 cells MNNG can circumvent the loss of wild-type p53 function and induce critical downstream regulatory events leading to transcriptional activation of p21. Present results indicate that the p53-independent up-regulation of p21 by MNNG is likely responsible for the inhibition of cyclin/Cdk complex kinase activity rather than the down-regulation of cyclins and Cdks expression. These novel phenomena have not been previously described and provide important new insights into the possible biological effects of MNNG.

• Journal of Nutrition and Health
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• v.56 no.6
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• pp.602-614
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• 2023

Purpose: The balance between synthesis and degradation of proteins plays a critical role in the maintenance of skeletal muscle mass. Mitochondrial dysfunction has been closely associated with skeletal muscle atrophy caused by aging, cancer, and chemotherapy. Polygalacin D is a saponin derivative isolated from Platycodon grandiflorum (Jacq.) A. DC. This study aimed to investigate the effects of polygalacin D on myoblast differentiation and muscle atrophy in association with mitochondrial function in in vitro and in zebrafish models in vivo. Methods: C2C12 myoblasts were cultured in differentiation media containing different concentrations of polygalacin D, followed by the immunostaining of the myotubes with myosin heavy chain (MHC). The mRNA expression of markers related to myogenesis, muscle atrophy, and mitochondrial function was determined by real-time quantitative reverse transcription polymerase chain reaction. Wild type AB^* zebrafish (Danio rerio) embryos were treated with 5-fluorouracil, leucovorin, and irinotecan (FOLFIRI) with or without polygalacin D, and immunostained to detect slow and fast types of muscle fibers. The Tg(Xla.Eef1a1:mitoEGFP) zebrafish expressing mitochondria-targeted green fluorescent protein was used to monitor mitochondrial morphology. Results: The exposure of C2C12 myotubes to 0.1 ng/mL of polygalacin D increased the formation of MHC-positive multinucleated myotubes (≥ 8 nuclei) compared with the control. Polygalacin D significantly increased the expression of MHC isoforms (Myh1, Myh2, Myh4, and Myh7) involved in myoblast differentiation while it decreased the expression of atrophic markers including muscle RING-finger protein-1 (MuRF1), mothers against decapentaplegic homolog (Smad)2, and Smad3. In addition, polygalacin D promoted peroxisome proliferator-activated receptor-gamma coactivator (Pgc1α) expression and reduced the level of mitochondrial fission regulators such as dynamin-1-like protein (Drp1) and mitochondrial fission 1 (Fis1). In a zebrafish model of FOLFIRI-induced muscle atrophy, polygalacin D improved not only mitochondrial dysfunction but also slow and fast muscle fiber atrophy. Conclusion: These results demonstrated that polygalacin D promotes myogenesis and alleviates chemotherapy-induced muscle atrophy by improving mitochondrial function. Thus, polygalacin D could be useful as nutrition support to prevent and ameliorate muscle wasting and weakness.

• Journal of Aquaculture
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• v.19 no.2
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• pp.84-89
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• 2006

Effect of dietary inclusion of various sources of green tea on growth, immune system and challenging test of juvenile olive flounder Paralichthys olivaceus was investigated. Five experimental diets with triplicates were prepared: control, raw leaves, dry leaves, by-product and extract. Twenty five (an initial body weight of 52.5 g) were randomly distributed into 15 of 180 L flow-through tanks. Nutrient requirements of the experimental diets satisfied growth of juvenile olive flounder. The feeding trial lasted for 7 weeks. After 7-week feeding trial, blood were sampled from three randomly chosen fish for serum analysis of Iysozyme and bactericidal activity, and ten fish were infected with Edwardsiella tarda for challenging test from each tank. Weight gain (g/fish) of fish fed the diet containing extract and control diet was significantly higher than that of fish fed the other diets. Feed efficiency ratio for fish fed the diet containing extract and control diet was significantly higher than that for fish fed the diets containing raw leaves and by-product, but not significantly different from that for fish fed the diet containing dry leaves. Serum Iysozyme activity (units/ml) of fish fed the diets containing dry leaves and extract was significantly higher than that of fish fed the diets containing raw leaves and by-product, but not significantly different from that of fish fed the control diet. Serum bactericidal activity (${\times}10^6$ bacteria/ml) of fish fed the diet containing dry leaves and extract was significantly lower than that of fish fed the diets containing raw leaves, by-product and control diet in 3 hour. However, serum bactericidal activity of fish fed the diet containing extract was significantly lower than that of fish fed the other diets in 6 hour. And serum bacterial activity was low in fish fed the diets containing dry and raw leaves, by-product, and control in 6 hour in order. Accumulative mortality (%) of fish fed the control diet was low compared to that of fish fed the diets containing raw leaves and by-product, but high compared to that of fish fed the diets containing dry leaves and extract although no significant difference was found among treatments. In considering above results, dietary inclusion of extract and dry leaves of green tea seemed to be highly effective to improve immune system and endurance against E. tarda infection of juvenile olive flounder.

• Analytical Science and Technology
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• v.28 no.6
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• pp.361-369
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• 2015

The precise mechanism underlying the therapeutic efficacy of an extraction powder of Angelica gigas (AGE) for the treatment of degenerative osteoarthritis was investigated in primary cultured rabbit chondrocytes and in a monosodium-iodoacetate (MIA)-induced osteoarthritis rat model. The treatment with AGE (50 μg/mL) effectively inhibited NF-B activation. The anti-inflammatory mechanism was clarified by gelatin zymography and western blotting measurements of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) activities. The AGE (50 μg/mL) treatment significantly reduced MMP-9 activity. The constituents of AGE— decursinol, decursin, and decursinol angelate—were determined by LC-MS/MS after a 24 hr treatment of rabbit chondrocytes. The contents of the major products, decursin and decursinol angelate, were 3.62±0.47 and 2.14 ±0.36 μg/mg protein, respectively in AGE-treated (50 μg/mL) rabbit chondrocytes. An in vivo animal study on rats fed a diet containing 25, 50, and 100 mg/kg AGE for 3 weeks revealed a significant inhibition of the MMPs in the MIA-induced rat articular cartilage. The genetic expression of arthritic factors in the articular cartilage was examined by RT-PCR of collagen Type I, collagen Type II, aggrecan, and MMP (MMP3, MMP-9, MMP13). Specifically, AGE up-regulated the expression of collagen Type I, collagen Type II, and aggrecan and inhibited MMP levels at all tested concentrations. Collectively, AGE showed a strong specific site of action on MMP regulation and protected against the degeneration of articular cartilage via cellular regulation of MMP expression both in vitro and in vivo.

• Journal of Life Science
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• v.23 no.9
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• pp.1109-1117
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• 2013

Induction of G1 Arrest by Methanol Extract of Lycopus lucidus in Human Lung Adenocarcinoma A549 Cells Lycopus lucidus, a herbaceous perennial, is used as a traditional remedy in East Asia, including China and Korea. It has been reported that L. lucidus has anti-allergic effects, inhibitory effects on cholesterol acyltransferase in high glucose-induced vascular inflammation, and anti-proliferative effects in human breast cancer cells. However, the molecular mechanisms of the anti-cancer effects of L. lucidus have not yet been fully determined. In this study, we evaluated the anti-cancer effect and the mechanism of action of L. lucidus in human lung adenocarcinoma A549 cells using methanol extracts of L. lucidus (MELL). MELL treatment showed cytotoxic activity in a dose-dependent manner and induced G1 arrest in A549 cells. The induction of G1 arrest by MELL was associated with the up-regulation of phospho-CHK2 and the down-regulation of Cdc25A phosphatase. In addition, MELL treatment induced decreased expression of G1/S transition-related proteins, including CDK2, CDK4, CDK6, cyclin D1 and cyclin E. MELL also regulated the mRNA expression of CDK2 and cyclin E. On the other hand, the expression of p53 and the cyclin-dependent kinase inhibitor p21 was not induced by MELL. Collectively, these results suggest that MELL may exert an anti-cancer effect by cell cycle arrest at G1 phase through the ATM/CHK2/Cdc25A/CDK2 pathway in A549 cells.

• Journal of Chest Surgery
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• v.43 no.4
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• pp.356-363
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• 2010

Background: Connexin 43-mediated gap junctional communication plays an important role in atherosclerosis. Numerous studies have demonstrated a correlation between mitral valve annular calcification and atherosclerotic disease. However, the relevance of connexin 43 to mitral valve disease remains unclear. We hypothesized that the mechanism contributing to mitral valve disease is associated with alterations in cell-to-cell communication mediated by changes in Connexin 43 expression. Material and Method: Twenty male New Zealand rabbits were divided into two groups: animals in group 1 (n=10) were fed a normal chow diet, whilst those in group 2 (n=10) received a diet containing 1% cholesterol for 12 weeks. After sacrificing the animals, the mitral valves were excised and analyzed with immunohistochemical staining and Real-time Reverse Transcriptase polymerase chain reaction (real time RT-PCR). Result: Myofibroblasts and macrophages were found concentrated within the endothelial layer on the ventricular side of the leaflet in the cholesterol diet group. Immunohistochemial staining showed elevated expression of connexin43 in the cholesterol diet group. Real-time RT-PCR revealed increased connexin43 mRNA levels in mitral valves from hypercholesterolemic animals. Conclusion: Our finding that connexin43 expression is increased in mitral valves of hypercholesterolemic rabbits suggests that alterations in cell-to-cell communication via connexin43 containing gap junctions play a role in the development of mitral valve disease in hypercholesterolemia.

• Clinical and Experimental Pediatrics
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• v.48 no.12
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• pp.1378-1384
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• 2005

Purpose : We hypothesized dexrazoxane(DXR) and pentoxifylline(PTX) may prevent myocardial damage in adriamycin(ADR)-induced cardiomyopathic rat model. We also investigated their effects on the myocardial apoptosis and fibrosis in ADR induced cardiomyopathy. Methods : The six-week old female Spregue-Dawley rats were divided into control group(CNT, n=4), ADR group(n=6), ADR+DXR group(DXR, n=5), ADR+PTX group(PTX, n=6), ADR+DXR+PTX group(DXPT, n=5). ADR(5 mg/week, twice) was administrated intravenously to rats except CNT group to induce cardiomyopathy. The PTX(50 mg/kg/day) was administered daily from day-0 to Day-21. The DXR(100 mg/kg) was administered 30 minutes before each ADR injection. On day 21, the rats were sacrificed and the degree of histopathologic changes of hypercontraction band necrosis, cytoplasmic vacuolar change and fibrosis were scored. Immunohistochemical staining for Bcl-2 expression and RT-PCR for $TNF-{\alpha}$ and CTGF were performed. Results : Histopathological scores of myocardial damage were significantly higher in ADR rats than CNT rats(P<0.05), and significantly lower in DXPT rats than ADR rats(P<0.01). Myocardial fibrosis was prevented in both PTX rats and DXPT rats. The expression of Bcl-2 was weaker in ADR rats than that in CNT rats(P<0.05), and stronger in both DXR and DXPT rats than that in ADR rats (P<0.05). $TNF-{\alpha}$ concentration of ADR rats was not different from that of treated groups. Conclusion : DXR prevented myocyte apoptosis with increased Bcl-2 expression, and PTX prevented myocardial fibrosis in ADR induced cardiomyopathic rats. The combination therapy of DXR and PTX showed prevention of cardiomyopathy in ADR induced cardiomyopathy rat model.

• Radiation Oncology Journal
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• v.19 no.1
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• pp.16-20
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• 2001

Purpose : To evaluate the effectiveness and tolerance of the postoperative radiation therapy for patients with Stage III thymoma and to define the optimal radiotherapeutic regimen Materials and Methods : We retrospectively analyzed the records of 24 patients with Stage III thymoma who were referred for postoperative radiation therapy in our institution from June, 1987 to May, 1999. Surgical therapy consisted of total resection in one patient, subtotal resection in seventeen, and biopsy alone in six patients. Age of the patients was ranged from 20 to 62 years with mean age of 47 years. Male to female ratio was 14 to 10. Radiation therapy was delivered with linear accelerator producing either 6 MeV or 10 MeV photons. The irradiated volume included anterior mediastinum and known residual disease. The supraclavicular fossae were not irradiated. The delivered total dose was ranged from 30 to 56 Gy. One patient received 30 Gy and eighteen patients received minimum of 50 Gy. Follow up period was ranged from 12 months to 8 years with median follow up of 40 months. Results : The overall local control rate for entire group of patients was $67\%$ at 5 years. The cumulative local failure rates at one, three and five year were $18\%,\;28\%\;and\;33\%$, respectively. In patients treated with subtotal resection and biopsy alone, local control rate was $76\%\;and\;33\%$, respectively. The actuarial observed survival rate at 5 years was $57\%$, and actuarial adjusted survival at 5 years was $72\%$. The difference between 5 year survival rates for patients treated with subtotal resection and biopsy alone was not statistically significant $(62\%\;vs\;30\%)$. Conclusion : We might conclude that postoperative radiation therapy was safe and effective treatment for patients with Stage III thymoma. Postoperative radiation therapy is recommended in cases where tumor margin is close or incomplete resection is accomplished.