• Asian Pacific Journal of Cancer Prevention
• /
• 제15권6호
• /
• pp.2565-2570
• /
• 2014

H19 is an imprinted oncofetal gene, and loss of imprinting at the H19 locus results in over-expression of H19 in cancers. Aflatoxin B1(AFB1) is regarded as one of the most dangerous carcinogens. Exposure to AFB1 would most easily increase susceptibility to diseases such as hepatocellular carcinoma(HCC) but any possible relationship between AFB1 and H19 is not clear. In present study, we found that AFB1 could up-regulate the expression of H19 and promote cell growth and invasion by hepatocellular carcinoma HepG2 cells. Knocking down H19 RNA co ld reverse the effects of AFB1 on cell growth and invasion. In addition, AFB1 induced the expression of E2F1 and its knock-down could down-regulate H19 expression and suppress cell growth and invasion in hepatocellular carcinoma HepG2 cells. Furthermore, E2F1 over-expression could up-regulate H19 expression and promote cell growth and invasion, with binding to the H19 promoter being demonstrated by chromatin immunoprecipitation assays (ChIP). In summary, our results suggested that aflatoxin B1could promote cell growth and invasion in hepatocellular carcinoma HepG2 cells through actions on H19 and E2F1.

• 한국가금학회지
• /
• 제44권4호
• /
• pp.283-290
• /
• 2017

Totally, one hundred and sixty 1-day-old Ross 308 broiler chicks were fed with a diet containing 0, 0.5, 1.0, and 2.0 mg of aflatoxin $B_1(AFB_1)/kg$ of feed for 21 days. Body weight was lower for the $AFB_1$-treated broilers than for the control group. At 14 and 21 DPF, the broilers fed with 2.0 mg of $AFB_1/kg$ of feed weighed significantly lower than those of the other groups (p<0.05). Relative liver weights increased significantly in a dose-dependent manner, and relative spleen weights were significantly high in the chicks fed with 2.0 mg of $AFB_1/kg$ of feed at 21 DPF (p<0.001). Biochemical analyses showed that total protein and albumin levels decreased significantly at 7 and 14 DPF for the chicks of the group fed with 2.0 of mg $AFB_1/kg$ of feed, compared with those fed with 0.5 and 1.0 mg of $AFB_1/kg$ of feed (p<0.05). AST and ALT levels increased significantly at 14 and 21 DPF (p<0.05), and the AST levels, particularly, increased dose-dependently (p<0.05). Histopathological analyses showed that the liver tissues of the $AFB_1$-treated chicks showed significant lesions, including hemorrhage, hepatocyte necrosis, inflammatory cell infiltration, and fatty degeneration. The severity of both hepatocyte necrosis and inflammatory cell infiltration appeared to increase dose- and time-dependently. Similarly, hepatic fibrosis increased dose-dependently (p<0.05). The results of this study could improve our understanding of parameters used for evaluating aflatoxicosis in poultry.

• Journal of Microbiology and Biotechnology
• /
• 제27권1호
• /
• pp.57-66
• /
• 2017

Aflatoxins are classified as Group 1 (carcinogenic to humans) by the International Agency for Research on Cancer. In this study, a total of 134 fungal strains were isolated from 65 meju samples, and two fungal isolates were selected as potential aflatoxin $B_1$ ($AFB_1$)-biodetoxification fungi. These fungi were identified as Aspergillus oryzae MAO103 and A. oryzae MAO104 by sequencing the beta-tubulin gene. The two A. oryzae strains were able to degrade more than 90% of $AFB_1$ (initial concentration: $40{\mu}g/l$) in a culture broth in 14 days. The mutagenic effects of $AFB_1$ treated with A. oryzae MAO103 and MAO104 significantly decreased to 5.7% and 6.4%, respectively, in the frame-shift mutation of Ames tests using Salmonella typhimurium TA98. The base-substituting mutagenicity of $AFB_1$ was also decreased by the two fungi. Moreover, $AFB_1$ production by Aspergillus flavus was significantly decreased by the two A. oryzae strains on soybean-based agar plates. Our data suggest that the two $AFB_1$-detoxifying A. oryzae strains have potential application to control $AFB_1$ in foods and feeds.

• Applied Microscopy
• /
• 제21권1호
• /
• pp.63-76
• /
• 1991

Butylated hrdroxyanisole(BHA), a widely used food additive phenolic antioxidant, is known to inhibit cancer formations inducible with a wide variety of chemical carcinogens including aflatoxin $B_1(AFB_1)$. Thus, in the present study morphological characteristics underlying the hepatoprotective effects of BHA against $AFB_1$ inducible ultrastructural changes of hepatocytes have been examined. The obtained results are as follows : 1 . Livers obtained from rats treated with $AFB_1$ in vivo have been examined with transmission electron microscope. Among the many hepatocellular structural aberrations induced by $AFB_1$ treatment, the nuclear chromatins were found to be distributed irregularly('cap formation') and the nuclear membrane was found to be partially segregated. Furthermore, there were many lipid droplets, hyperplasia of smooth endoplasmic reticulum, dialated rough endoplasmic reticulum and, lysosomes arrested at various stages of its development. 2. Also, when $AFB_1$ was given in vitro to hepatocytes which have been isolated from untreated normal rats and examined under scanning electron microscope, there were much 'blobbing' phenomena resulting from cytoskeletal disturbances. 3. However, in the liver obtained from rats pretreated with BHA and then give the $AFB_1$, the observed morphological aberrations were in much reduced extent. Similarly, the BHA-hepatocytes had much decreased severity in the $AFB_1$ inducible blob formations.

• Toxicological Research
• /
• 제34권3호
• /
• pp.211-220
• /
• 2018

Early life exposure to aflatoxin B1 (AFB1) and low protein diet through complementary foods during weaning is common in parts of Africa and Asia. This study evaluated the effect of co-exposure to AFB1 and low protein diet on the extrahepatic tissues of rats. Twenty-four three-week old weanling male albino rats were used for this study and were randomly assigned into four groups: group 1 served as control and was fed normal protein diet (20% protein), group 2 was fed low protein diet (5% protein), group 3 was fed normal protein diet + 40 ppb AFB1 while group 4 received low protein diet + 40 ppb AFB1, all for eight weeks. Afterward, biomarkers of anemia (packed cell volume (PCV), hemoglobin) and kidney function (urea, uric acid, and creatinine) were determined in the blood while biomarkers of oxidative stress were determined in the tissues spectrophotometrically. Co-exposure to AFB1 and low protein diet significantly (p < 0.05) decreased body weight gain and PCV, increased biomarkers of kidney functions and induced oxidative stress in the tissues studied. There was significant (p < 0.05) reduction in glutathione concentration while TBARS was significantly increased in the tissues. Co-exposure to AFB1 and low protein diet had additive effects on decreasing the weight gain and potentiation effect of kidney dysfunction in the rats. The co-exposure also decreased antioxidant enzymes and increased oxidant status in the tissues. Our results demonstrate that this co-exposure has deleterious health effects on extrahepatic tissues and should be a public health concern especially in developing countries where AFB1 contamination is common.

• 한국식품영양학회지
• /
• 제16권4호
• /
• pp.303-309
• /
• 2003

직ㆍ간법 변이원과 산화적 돌연변이원에 대한 송화분 추출물의 항돌연변이원성에 대하여 Ames test로 조사하였다. 메탄을 추출물을 이용하여, 10종의 돌연변이에 대한 돌연변이 억제효과를 검색한 결과 S. typhimurium TA98에서는 daunomycin, AFB$_1$과 Trp-P-1의 변이원성에 대해서만 각각 17.8, 82.2, 80.9%의 돌연변이 억제효과를, S. typhimurium TA100에서는 AFB$_1$의 변이원성에 대해서만 72.3%의 돌연변이 억제효과를 나타내었으며, S. typhimurium TA102, 104에서 t-과산화부틸과 $H_2O$$_2$의 돌연변이원성에 대한 메탄을 추출물의 돌연변이 억제 효과는 t-과산화부틸을 돌연변이원으로 한 S. typhimurium TA102에서 16.3%의 억제효과를 선택적으로 나타내었다. 따라서 메탄을 추출물을 클로르포름, 에틸아세테이트, 부탄올, 물 순으로 순차용매 분리한 다음, 이 분획물에 대한 항돌연변이원성을 검색하였다. 그 결과 S. typhimurium TA98에서 daunomycin, AFB$_1$과 Trp-P-1에 대해서 플로로포름 분획물은 각각 55.6, 93.7, 93.5%, 에틸아세테이트 분획물은 각각 11.4, 74.3, 85.2%, 부탄을 분획물에서는 10.9, -5.6, 6.8%, 물 분획물은 각각 -3.4, -3.8, 4.6%의 돌연변이 억제효과를 나타내었다. S. typhimurium TA100에서는 AFB$_1$에 대해 클로로포름 분획물과 에틸아세테이트 분획물이 각각 95.1, 62.5%의 억제효과를 나타내었으며, S. typhimurium TA102에서는 t-과산화부틸에 의해 유도된 산화적 돌연변이에 대해 클로로포름 분획물이 93.6%로 매우 강한 억제효과를 나타내었으며, 기타 분획물에서는 매우 낮은 억제효과를 나타내었다.

• 한국식품영양과학회지
• /
• 제36권2호
• /
• pp.163-173
• /
• 2007

Aflatoxin은 Aspergillus속 곰팡이로부터 생성되며 사람에게 있어서 간독성 및 간암을 유발하는 잠재력을 가진 곰팡이 독소이며, 지질과산화 반응은 aflatoxin $B_1$에 의한 세포 산화적 손상 시 발생하는 주요 현상 중의 하나이다. 방사선은 수술, 항암약물요법과 더불어 임상 시 중요한 치료방법이나, 정상세포에 방사선을 조사하였을 때 반응성이 높은 활성산소와 과산화라디칼$(OH{\cdot})$을 생성하여 세포막의 불포화지방산을 지질과산화물로 변성시켜 세포 산화적 손상을 일으킨다. 따라서 본 연구의 목적은 aflatoxin $B_1$과 방사선조사 후 유도된 간과 혈청의 지질성분 및 지방산 조성에 미치는 vitamin C의 영향을 조사하기 위해 수행되었다. X-ray 조사는 실험기간 내 단 1회로 실험사육기간 첫 일에 조사하였고 X-ray 조사 후 vitamin C를 투여하였으며 vitamin C 투여 1시간 후 $AFB_1$을 투여하였다. Vitamin C와 $AFB_1$은 모두 복강투여로 실험 사육 첫 일부터 1회 시작하여 3일에 한번씩, 5회 반복 투였으며 실험동물 사육기간은 총 15일로 하였다. 혈청 총콜레스테롤 농도는 $1\sim5$군에서 유의적인 차이를 볼 수 없었는데 방사선과 $AFB_1$을 함께 처리한 6군에서는 $130.37{\pm}9.14mg/dL$로서 전군에서 가장 높은 수치를 나타낸 반면 6군에 vitamin C를 혼합 투여한 7군에서는 $90.23{\pm}6.15mg/dL$로서 가장 낮았으며 이는 중성지질과 유사한 경향이었다. 또한 간장의 총콜레스테롤과 유리 콜레스테롤도 이와 유사한 경향이었다. HDL 농도는 방사선과 $AFB_1$을 함께 처리한 것에 vitamin C를 혼합 투여한 7군이 $59.57{\pm}9.56mg/dL$로서 p<0.01 수준에서 현저히 증가하였다. 혈청의 인지질과 콜레스테롤 에스테르의 지방산 조성에서 vitamin C를 혼합 투여한 3,5,7군에서 PUFA 함량이 증가한 반면, SFA 함량은 감소하여 P/S 비율, n-3P/n-6P 비율은 증가하는 경향이었으며 이는 간장의 인지질, 콜레스테롤 에스테르, 총 지질의 지방산조성에서도 같은 경향을 볼 수 있었다.

• 한국미생물·생명공학회지
• /
• 제24권4호
• /
• pp.525-528
• /
• 1996

To investigate the inhibitory effect of soybean and Korean traditional fermented soybean products on the chemically induced mutagenesis, we extracted soybean, Kanjang, Doenjang, Kochujang, and Chongkukjang with water, methanol and hexane. Inhibitory effect of the extracts was assayed by the SOS chromotest using Escherichia coli PQ37 as a test strain. 4-nitroquinoline-1-oxide(4NQO), N-methyl-N'-nitro-N-nitrosoquanidine(MNNG), and aflatoxin B$_{1}$(AFB$_{1}$) were used as mutagens. Methanol extracts showed relatively higher inhibitory effect than water and hexane extracts. Methanol extracts of soybean, Doenjang, Kochujang, and Chonhkukjang showed inhibitory effect of 68.4, 96.3, 17.5, and 100.9% against MNNG, and 28.6, 109.1, 41.3, and 101.8% against AFB$_{1}$, respectively. Doenjang methanol extract showed inhibitory effect of 51.0, 96.3, and 109.1% against 4NQO, MNNG, and AFB$_{1}$, respectively. Methanol extract of Doenjang showed dose-dependent inhibitory effect against 4NQO, MNNG, and AFB$_{1}$. Inhibitory effect of heat-treated Doenjang and Chongkukjang methanol extracts on the mutagenecity of MNNG and AFB$_{1}$ was remained over 95% of the inhibitory effect of heat-untreated extracts, demonstrating the heat stability of the potent antimutagenic activity.

• 한국식품영양과학회지
• /
• 제19권2호
• /
• pp.156-162
• /
• 1990

Antimutagenic effect of doenjag (Korean fermented soy paste) on mutagenesis induced by aflatoxin B1 (AFB1) in Salmonella typhimurium strains TA98 and TA100 was studied. AFB1 revealed maximum mutagenicity at dose level of 1 $\mu$g/plate with metabolic activation system in both strains. Strong antiutagenic activity toward AFB1 was completely inhibited at the level of 50% of the doenjang extract. At the same concentration 64-66% and 39-53% of the AFB1 induced mutageneses were blocked when the methanol extracts of raw and cooked soybeans were added in the system respectively Raw soybeans showed higher ihhibition rate to the mutagenicity than cooked soybeans but the fermented soybeans(doenjang) was the most effective (p<0.05) Other soybean fermented foods such as commercial doenjang natto and miso were also exhibited some antimutagenic activities however the traditional doenjang was the most effective and then commercial doenjang. Natto and miso were less effective.

• 한국식품위생안전성학회지
• /
• 제12권4호
• /
• pp.321-327
• /
• 1997

The antimutagenic effects of juices and methanol extracts from cruciferous vegetables (cabbage, red cabbage, Korean cabbage, kale, cauliflower, broccoli, radish root, leafy radish, rape leaves and shepherd's purse) on the mutagenicity induced by aflatoxin B1(AFB1) and N-methyl-N'-nitrosoguanidine(MNNG) were studied using Salmonella assay system. In the case of juices from the cruciferous vegetables, the juices of cabbage, kale, cauliflower and radish root in the concentrations of 50, 200 and 500 ${mu}ell$/plate considerably decreased the mutagenicity induced by AFB1, and the juices of cabbage and broccoli in the concentrations of 200 and 500${mu}ell$/plate significantly reduced the mutagenicity induced by MNNG. The antimutagenic activities of the juices against AFB1 were stronger than those against MNNG. In the case of methanol extracts from the cruciferous vegetables, the methanol extracts of kale, broccoli and shepherd'purse appeared to inhibit the mutagenicity induced by AFB1 and MNNG in Salmonella typhimurium test strains. The effects of the juices against mutagens quite different from ones of the methanol extracts. The juice of cabbage showed antimutagenicity, but its methanol extract was less effective. However, both juices and methanol extracts from kale and broccoli exhibited strong antimutagenic activities against the mutagens.