• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.383-390
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• 2013

Mistlero C was shown to be non-genotoxic in a series of genotoxicity tests, including a bacterial reverse mutation test and a combined in vivo mammalian erythrocyte micronucleus test. In a bacterial reverse mutation assay, no significant increases in the number of revertant colonies, compared to the negative control, was detected in $5,000{\mu}g/plate$ of Mistlero C. In addition, with Mistlero C, no changes were shown in the number of micronucleated polychromatic erythrocytes (MNPCE) among 2,000 polychromatic erythrocytes compared to the negative control. Mistlero C was administered orally in rats to investigate acute toxicity. The $LD_{50}$ values in rats were above 2,000 mg/kg. In a repeated dose, 13-week, oral toxicity study conducted in rats, no compound-related adverse effects were shown at doses of Mistlero C of up to 1,000 mg/kg body weight/day. The results of these studies support the safe use of Mistlero C in food for human consumption.

• The Korean Journal of Nuclear Medicine
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• v.27 no.1
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• pp.118-122
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• 1993

To evaluate the genotoxic effect of $^{131}I$, lymphocytes from 9 patients who underwent large dose (150 mCi) $^{131}I$ therapy after total thyroidectomy were studied for sister chromatid exchanges (SCE) before and after their first radioiodine treatments. Frequency of SCE (FSCE) was counted in chromosomes of 30 lymphocytes in each patients, and was expressed as numbers of SCE per cell. Numbers of leukocytes were also observed during $^{131}I$ therapy. Pretreatment FSCE ($4.2{\pm}0.7$) was not different from the control ($3.8{\pm}0.4$, p=0.17). However, the frequency was significantly elevated after $^{131}I$ administration (at the second day, $7.9{\pm}0.8$, p<0.001) and was diminished but still significantly elevated after a week (at 9th day, $6.4{\pm}0.6$, p<0.001). While counts of leukocytes in the peripheral blood showed no change (p> 0.05). In conclusion, chromatids of human lymphocytes were significantly damaged after $^{131}I$ treatment without any bone marrow supression. And the repair of SCE was not complete within one week.

• Journal of Food Hygiene and Safety
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• v.33 no.3
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• pp.207-213
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• 2018

This study aimed to evaluate the genotoxicity of Litsea japonica fruit-hexane extract (LJF-HE). In order to examine the genotoxicity, we carried out bacterial reverse mutation assay, chromosome aberration assay, and a micronucleus induction (MN) test according to the OECD and the Korea Ministry of Food and Drug Safety (MFDS) toxicity test guidelines. In the bacterial reverse mutation assay, no significant increase in revertant colonies, nor bacterial toxicity, was observed in the LJF-HE treatment group, regardless of the absence or presence of metabolic activation by the S9 mixture. However, in the positive control group, revertant colony counts were shown to be more than twice that of the negative control group. The chromosome aberration test showed that the repetition rate of abnormal chromosome aberration was less than 5%, regardless of the treatment time, and with or without the S9 mixture. No significant change was observed when (p < 0.05) compared with the negative control group. The micronucleated polychromatic erythrocytes (MNPCE) repetition rate of the polychromatic erythrocytes (PCE) showed no significant changes when compared with the negative control group (p < 0.05). The PCE portion of total erythrocytes also showed no significant changes (p < 0.05). These results showed that LJF-HE had no significant genotoxic effects.

• Journal of Periodontal and Implant Science
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• v.38 no.sup2
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• pp.317-324
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• 2008

Purpose: Aggregatibacter actinomycetemcomitans was associated with localized aggressive periodontitis, endocarditis, meningitis, and osteomyelitis. The cytolethal distending toxin (CDT) of A. actinomycetemcomitans was considered as a key factor of these diseases is composed of five open reading frames (ORFs). Among of them, An enzymatic subunit of the CDT, CdtB has been known to be internalized into the host cell in order to induce its genotoxic effect. However, CdtB can not be localized in host cytoplasm without the help of a heterodimeric complex consisting of CdtA and CdtC. So, some studies suggested that CdtC functions as a ligand to interact with GM3 ganglioside of host cell surface. The precise role of the CdtC protein in the mechanism of action of the holotoxin is unknown at the present time. The aim of this study was to generate recombinant CdtC proteins expression from A. actinomycetemcomitans, through gene cloning and protein used to investigate the function of Cdt C protein in the bacterial pathogenesis. Materials and Methods: The genomic DNA of A. actinomycetemcomitans Y4 (ATCC29522) was isolated using the genomic DNA extraction kit and used as template to yield cdtC genes by PCR. The amplifed cdtC genes were cloned into T-vector and cloned cdt C gene was then subcloned to pET28a expression vector. The pET28a-cdtC plasmid expressed in BL21 (DE3) Escherichia coli system. Diverse conditons were tested to opitimize the expression and purification of functional CdtC protein in E. coli. Results: In this study we reconstructed CdtC subunit of A. actinomycetemcomitans Y4 and comfirmed the recombinant CdtC expression by SDS-PAGE and Western Blotting. The expression level of the recombinant CdtC was about 2% of total bacterial proteins. Conclusion: The lab condition of procedure for the purification of functionally active recombinant CdtC protein is established. The active recombinant CdtC protein will serve to examine the role of CdtC proteins in the host recognition and enzyme activity of CDT and investigate the pathological process of A. actinomycetemcomitans in periodontal disease.

• Food Science and Preservation
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• v.13 no.4
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• pp.524-529
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• 2006

Gamma irradiation at 30 kGy was applied to cereal powders to evaluate their possible genotoxicity. The genotoxicity of 30 kGy-irradiated cereal powders was evaluated by Salmonella typhimurium reversion assay, chromosomal aberration test and in vivo micronucleus assay. The result were negative in the bacterial reversion assay with S. typhimurium TA98, IA100, TA1535 and TA1537. No mutagenicity was detected in the assay with and without metabolic activation. In chromosomal aberration tests with CHL cells and in vivo mouse micronucleus assay, no significant difference in the incidences of chromosomal aberration and micronuclei was observed between non-irradiated and 30 kGy-irradiated cereal powders. These result indicate that cereal powders irradiated at 30 kGy did not show any genotoxic effect under these experimental conditions.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.3
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• pp.211-216
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• 2016

Micronucleus test is genotoxicity assay for detection of micronuclei in the cytoplasm of interphase cells. The reduction and replacement of in vivo toxicity testing on animals require the development of in vitro models to predict the genotoxicity or other tests for cosmetic products. In this study, we evaluated a genotoxicity assay for topically applied chemicals using a three-dimensional human reconstructed skin model, KeraSkin$^{TM}$. Two genotoxins, mitomycin C (MMC) and methyl methanesulfonate (MMS), induced significant dose-related increases in cytotoxicity and micronuclei induction in the skin model. In contrast, two non-genotoxins, 4-nitrophenol (4-NP) and trichloroethylene (TCE), induced cytotoxicity but not micronucleus formation. In conclusion, micronucleus test using human skin model may be useful for predicting in vitro genotoxic potentials of cosmetic products.

• YAKHAK HOEJI
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• v.40 no.5
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• pp.608-615
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• 1996

6-[(N-3,4-Difluorophenyl)amino]-7-chloro-5,8-quinolinedione(RCK4) was tested for antifungal activities, against systemic infections with Candida albicans in normal mice. The therapeutic potential of RCK4 had been assessed in comparison with ketoconazole and fluconazole. RCK4 had $ED_{50},\;0.30{\pm}0.14$ but ketoconazole and fluconazole had $ED_{50},\;8.00{\pm}0.73,\;10.00{\pm} 0.43mg/kg$ respectively. Intraperitoneally administered RCK3 at the $ED_{50}$ for 7 days and 14 days reduced Candida albicans colony count in the kidneys and liver as well as ketoconazole and fluconazole at these $ED_{50}$. And administered RCK4 at the $ED_{50}$ for 14 days improved survival rates as well as ketoconazole. Acute oral toxicity studies of RCK4 were carried out in ICR mice of both sexes. These acute oral toxicities of RCK4 were low and $LD_{50}$ values were over 2,850mg/kg in ICR mice. The genotoxicities of RCK4 had been evaluated. RCK4 was negative in Ames test with Salmonella typhimurium and chromosomal aberration test in CHL cells. The clastogenicity was tested on the RCK4 with in vivo mouse micronucleus assay. RCK4 did not show any clastogenic effect in mouse peripheral blood and was negative in mouse micronucleus assay. These results indicate that RCK4 has no genotoxic potential under these experimental conditions.

• Archives of Pharmacal Research
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• v.21 no.4
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• pp.391-397
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• 1998

The toxicity evaluation of oriental herbal drugs is of great concern at present. Bojungchisup-tang (BCST, in Korean), a decocted medicine of oriental herbal mixture, is now well used in clinic at oriental hospitals for the treatment of edema of several diseases in practice. However, the toxicity of the oriental herbal decocted medicines such as genetic toxicity is not well defined until now. In this respect, to clarify the genetic toxicity of BCST, in vitro chromosome aberration assay with Chinese hamster lung (CHL) fibroblasts and in vivo supravital micronucleus assay with mouse peripheral reticulocytes were performed in this study. In the chromosome aberration assay, we used 5,000 $\mu\textrm{g}$/ml BCST as maximum concentration because no remarkable cytotoxicity in CHL cells was observed both in the presence and absence of S-9 metabolic activation system. No statistical significant differences of chromosome aberrations were observed in CHL cells treated with 5,000, 2,500 and 1,250 $\mu\textrm{g}$/ml BCST for 6 hour both in the presence and absence of S-9 metabolic activation. However, very weak positive result (6.5-8.0% aberration) of BCST was obtained in the absence of S-9 metabolic activation system at 5,000 $\mu\textrm{g}$/ml BCST when treated for 24 hour, i.e. 1.5 normal cell cycle time. And also, in vivo clastogenicity of BCST was studied by acridine orange-supravital staining micronucleus assay using mouse peripheral reticulocytes. We used 2,000 mg/kg as the highest oral dose in this micronucleus assay because no acute oral toxicity of BCST was observed in mice. The optimum induction time of micronucleated reticulocytes (MNRETS) was determined as 36 hours after oral administration of 2,000 mg/kg BCST. No significant differences of MNRETs between control and BCST treatment groups were observed in vivo micronucieus assay. From these results, BCST revealed very weak positive result in chromosome aberration assay in vitro with CHL cells and no clastogenicity in micronucieus assay in vivo.

• Development and Reproduction
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• v.25 no.1
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• pp.15-24
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• 2021

Benzo[a]pyrene (B[a]P) is a potent carcinogen and is classified as an endocrine-disrupting chemical. In mammalian testes, Sertoli cells support spermatogenesis. Therefore, if these cells are negatively affected by exposure to xenotoxic chemicals, spermatogenesis can be seriously disrupted. In this context, we evaluated whether mouse testicular TM4 Sertoli cells are susceptible to the induction of cytotoxicity-mediated cell death after exposure to B[a] P in vitro. In the present study, while B[a]P and B[a]P-7,8-diol were not able to induce cell death, exposure to BPDE resulted in cell death. BPDE-induced cell death is accompanied by the activation of caspase-3 and caspase-7. Depolarization of the mitochondrial membrane and cytochrome c release from mitochondria were observed in benzo[a]pyrene-7,8-diol-9,10-epoxide (BPDE)-treated cells. These results indicate that TM4 cells are susceptible to apoptosis in a caspase-dependent manner. Western blot and reverse transcription-polymerase chain reaction (RT-PCR) analyses showed that aryl hydrocarbon receptor (AhR) expression was almost undetectable in TM4 cells and that its expression was not altered after B[a]P treatment. This indicates that TM4 cells are nearly AhR-deficient. In TM4 cells, the CYP1A1 protein and its activity were not present. From these results, it is clear that AhR may be a prerequisite for CYP1A1 expression in TM4 cells. Therefore, TM4 cells can be referred to as CYP1A1-deficient cells. Thus, TM4 Sertoli cells are believed to have a rigid and protective cellular machinery against genotoxic agents. In conclusion, it is suggested that tolerance to B[a]P cytotoxicity is associated with insufficient AhR and CYP1A1 expression in testicular Sertoli cells.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.3
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• pp.325-334
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• 2013

The objective of this study was to compare the content and metabolic activities between fresh pine needle juice (PNJ) and fermented pine needle juice (FPNJ). A variety of factors were measured, including total phenolic content (TPC), antioxidant activity [DPPH radical scavenging activity (RSA), total radical-trapping antioxidant potential (TRAP), oxygen radical absorbance capacity (ORAC), cellular antioxidant capacity (CAC)], anti-genotoxic activity, ${\alpha}$-glucosidase inhibitory activity, and angiotensin converting enzyme (ACE) inhibitory activity. The TPC was $17.3{\pm}0.2$ and $4.6{\pm}0.0$ mg GAE/g in PNJ and FPNJ, respectively. The DPPH RSA, TRAP, and ORAC values increased in a dose-dependent manner for both PNJ and FPNJ, with significantly higher activities in PNJ than FPNJ. The CAC against AAPH-induced oxidative stress in HepG2 cells was protected by both PNJ and FPNJ. Pretreatment with PNJ and FPNJ in human leukocytes produced significant reductions in $H_2O_2$-induced DNA damage at a concentration of $50{\mu}g/mL$. ${\alpha}$-Glucosidase inhibitory activity was significantly higher in FPNJ than PNJ. The ACE inhibitory activity was about 87.1% and 60.0% in 1:1 diluted PNJ and FPNJ, respectively. This study suggests that the fermentation of PNJ could enhance the regulation of blood glucose metabolism and both PNJ and FPNJ might be a new potential source of natural antioxidant, anti-diabetic, and anti-hypertensive agents applicable to food.