• Title/Summary/Keyword: Metabolic activation

Search Result 429, Processing Time 0.023 seconds

Genotoxicity Study of HM10411, Recombinant Human Granulocyte Colony Stimulating Factor (재조합 인과립구 콜로니 자극인자 HM10411의 유전독성 연구)

  • 권정;이미가엘;홍미영;조지희;정문구;권세창;이관순
    • Biomolecules & Therapeutics
    • /
    • v.10 no.4
    • /
    • pp.268-273
    • /
    • 2002
  • Mutagenic potential of HM10411 (recombinant human granulocyte colony stimulating factor) was evaluated by bacterial reverse mutation test, in vitro chromosome aberration test and in vivo micronucleus test. The bacterial reverse mutation test was performed using the histidine auxotroph strains of Salmonella typhimurium TA100, TA1535, TA98, TA1537 and tryptophan auxotroph strain of Escherichia coli WP2 uvrA. The negative results of the bacterial reverse mutation test suggest that HM10411 does not induce mutation, in the genome of Salmonella typhimurium and E. coli under the conditions used. In addition, it has little clastogenicity either in vitro chromosome aberration test or in vivo micronucleus test. For in vitro chromosomal aberration test, Chinese hamster lung(CHL) cells were exposed to HM10411 of 23, 46 or 92 $\mu\textrm{g}$/ml for 6 or 24 hours in the absence and for 6 hours in the presence of metabolic activation system. There was no significant increase in the number of aberrant metaphase in HM 10411-treated groups at any dose levels both in the presence and absence of metabolic activation system. The micronucleus test was carried out using specific pathogen free(SPF) 7-week old male ICR mice, The test item, HM10411 was intraperitoneally administered at 1150, 2300 or 4600 $\mu\textrm{g}$/kg once a day for 2 consecutive days. There was no significant increase in the frequencies of micronucleated polychromatic erythrocytes(PCEs) at any treated groups compared with negative control group. Therefore, these results demonstrate that the test item, HM10411, was not mutagenic under the condition of these studies.

Genotoxicity Study of ChondroT (ChondroT의 유전독성 연구)

  • Kim, Sun-Gil;Kim, Joo Il;Kim, Ji-Hoon;Yoon, Chan Suk;Jeong, Ji-Won;Na, Chang-Su;Kim, Seon-Jong
    • Journal of Korean Medicine Rehabilitation
    • /
    • v.31 no.1
    • /
    • pp.59-79
    • /
    • 2021
  • Objectives This study was performed to observe the genotoxic effect of the ChondroT. Methods To evaluate the genotoxicity of ChondroT, an experiment of bacterial reverse mutation test, in vitro mammalian chromosomal aberration test and mammalian erythrocyte micronucleus test in mouse was conducted. Results TA98, TA100 and TA1537 strains in the absence of metabolic activation system (S9 mix), the number of revertant colonies being greater than 2-fold of the respective negative control value. Both in -S9 mix and +S9 mix, the frequencies of aberration cells with structural aberration and numerical aberrations of chromosome were less than 5%. There was no increase of polychromatic erythrocyte with one or more micronuclei at any dose of test substance compared to the negative control group (p<0.05). Conclusions In TA98, TA100 and TA1537 strains in the absence of metabolic activation system (S9 mix), the number of revertant colonies was greater than 2-fold of the respective negative control value, showing positive results. ChondroT was considered to be non-clastogenic to Chinese hamster lung (CHL/IU) cells under the present experimental condition. and ChondroT was determined not to induce an increased frequency of micronuclei in the bone marrow cells of male ICR mice under the present experimental condition.

Involvement of Oxidative Stress and Poly(ADP-ribose) Polymerase Activation in 3-Nitropropionic Acid-induced Cytotoxicity in Human Neuroblastoma Cells

  • Nam, Eun-Joo;Lee, Young-Jae;Oh, Young-Ah;Jung, Jin-Ah;Im, Hye-In;Koh, Seong-Eun;Maeng, Sung-Ho;Joo, Wan-Seok;Kim, Yong-Sik
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.7 no.6
    • /
    • pp.325-331
    • /
    • 2003
  • 3-Nitropropionic acid (3-NP) inhibits electron transport in mitochondria, leading to a metabolic failure. In order to elucidate the mechanism underlying this toxicity, we examined a few biochemical changes possibly involved in the process, such as metabolic inhibition, generation of reactive oxygen species (ROS), DNA strand breakage, and activation of Poly(ADP-ribose) polymerase (PARP). Exposure of SK-N-BE(2)C neuroblastoma cells to 3-NP for 48 h caused actual cell death, while inhibition of mitochondrial function was readily observed when exposed for 24 h to low concentrations (0.2${\sim}$2 mM) of 3-NP. The earliest biochemical change detected with low concentration of 3-NP was an accumulation of ROS (4 h after 3-NP exposure) followed by degradation of DNA. PARP activation by damaged DNA was also detectable, but at a later time. The accumulation of ROS and DNA strand breakage were suppressed by the addition of glutathione or N-acetyl-L-cysteine (NAC), which also partially restored mitochondrial function and cell viability. In addition, inhibition of PARP also reduced the 3-NP-induced DNA strand breakage and cytotoxicity. These results suggest that oxidative stress and activation of PARP are the major factors in 3-NP-induced cytotoxicity, and that the inhibition of these factors may be useful in protecting neuroblastoma cells from 3-NP-induced toxicity.

Effects of Flos Sophorae Ethanol Extract on NF-${\kappa}B$ Dependent MMP-9 Expression in Human Breast Cancer Cell (유방암세포에서 괴화 에탄올 추출물의 NF-${\kappa}B$ 의존적인 MMP-9 발현의 조절 규명을 위한 연구)

  • Kim, Jeong Mi;Lee, Young Rae;Hwang, Jin Ki;Kim, Mi Seong;Kim, Ha Rim;Park, Yeon Ju;You, Yong Ouk;Kim, Seong Cheol;Ryu, Do Gon;Kwon, Kang Beom
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.28 no.1
    • /
    • pp.22-28
    • /
    • 2014
  • Flos Sophorae, the dried flower bud of Sophora japonica L, possesses anti-inflammatory properties, prevents and treats blood capillary and hypertension diseases and can also be used as a hemostat. However, the effect of Flos Sophorae on breast cancer invasion is unknown. Matrix metalloproteinase-9 (MMP-9), which degrades the extracellular matrix, is a major component in cancer cell invasion. In this study, we investigated the inhibitory effect of Flos Sophorae extract (FSE) on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced Matrix metalloproteinase-9 (MMP-9) expression and cell invasion, as well as the molecular mechanisms involved in Michigan Cancer Foundation-7 (MCF-7) cells. FSE inhibited the TPA-induced transcriptional activation of nuclear factor-kappa B (NF-${\kappa}B$). These results indicate that FSE-mediated inhibition of TPA-induced MMP-9 expression and cell invasion involves the suppression of NF-${\kappa}B$ pathway in MCF-7 cells. Thus, FSE may have therapeutic potential for controlling breast cancer invasiveness.

A STUDY ON THE EFFECT OF SIB ZUN DAE BO TANG ADMINISTERED IN RABBIT WITH HEPATIC DISFUNCTION ON THE RATE OF RECOVERY (십전대보탕액(十全大補湯液)을 투여(投與)하여 가토간손상(家兎肝損傷)의 회복(回復)에 관(關)한 실험적(實驗的) 연구(硏究))

  • Kim, Han-Suk
    • The Journal of Internal Korean Medicine
    • /
    • v.1 no.1
    • /
    • pp.78-84
    • /
    • 1976
  • The SIB ZUN DAE BO TANG is one of the prevailing tonics appeared at first time on TAE PYUNG HOE MIN HAW ZE GUK BANG in Song’s dynasty and have been widely used up to now. To observe the metabolic effects of Thioacetamide from the SIB ZUN DAE BO TANG, the following experiment was performed. 1. The activation of G.O.T. and G.P.T. to blood serum have been decreased when Thioacetamide was administrated into the rabbit. 2. The coefficiency of the SIB JUN DAE BO TANG appears in 3 hours after administrate and it decreases gradually along with it’s time(1st, 2nd, 3rd day) but the coefficiency of the G.P.T. was more apparent on 2nd, 3rd and 5th day. 3. When administrating Thioacetamide, the total amount of cholesterol grows rapidly up to 3rd day and it continuously grows after the 3rd day. But when administrating SIB ZUN DAE BO TANG, the cholesterol amount in blood grows up to 3rd day, but it decreases gradually after it on the other day. The conclusion of the above experiments shows that the prescription (SIB ZUN DAE BO TANG) improves the metabolic deficiency and the recovery and remedy of diseases.

  • PDF

Induction of Lipin1 by ROS-Dependent SREBP-2 Activation

  • Seo, Kyuhwa;Shin, Sang Mi
    • Toxicological Research
    • /
    • v.33 no.3
    • /
    • pp.219-224
    • /
    • 2017
  • Lipin1 was identified as a phosphatidate phosphatase enzyme, and it plays a key role in lipid metabolism. Since free radicals contribute to metabolic diseases in the liver, this study investigated the effects of free radicals on the regulation of Lipin1 expression in Huh7 and AML12 cells. Hydrogen peroxide induced mRNA and protein expression of Lipin1 in Huh7 cells, which was assayed by quantitative RT-PCR and immunoblotting, respectively. Induction of Lipin1 by hydrogen peroxide was confirmed in AML12 cells. Hydrogen peroxide treatment significantly increased expression of sterol regulatory element-binding protein (SREBP)-2, but not SREBP-1. Moreover, nuclear translocation of SREBP-2 was detected after hydrogen peroxide treatment. Hydrogen peroxide-induced Lipin1 or SREBP-2 expression was significantly reduced by N-acetyl-$\small{L}$-cysteine treatment, indicating that reactive oxygen species (ROS) were implicated in Lipin1 expression. Next, we investigated whether the hypoxic environments that cause endogenous ROS production in mitochondria in metabolic diseases affect the expression of Lipin1. Exposure to hypoxia also increased Lipin1 expression. In contrast, pretreatment with antioxidants attenuated hypoxia-induced Lipin1 expression. Collectively, our results show that ROS activate SREBP-2, which induces Lipin1 expression.

Inhibitory Effect of Chrysanthemum zawadskii var. latilobum Kitamura Extracts against Mutagenicity of Cigarette Smoke Condensates (CSC) (담배연기응축물로 유도된 돌연변이와 구절초 추출물의 억제 효과)

  • Lee, Jin-Hee;Lim, Heung-Bin
    • Korean Journal of Medicinal Crop Science
    • /
    • v.19 no.3
    • /
    • pp.170-176
    • /
    • 2011
  • This study was carried out to investigate whether Chrysanthermum zawadskii var. latilobum Kitamura (C. zawadskii) extracts has an inhibitory effect against the mutagenicity by cigarette smoke condensates (CSC). C. zawadskii was extracted with 70% ethanol and the yield was 18.5%. We further fractioned 70% ethanol extract sequentially to diethylether, chloroform, dichloromethane, and aqueous water, and gained the yield of 17.5%, 5.6%, 5.8%, 32.8% and 35.5%, respectively. In the Ames test, there was no mutagenic effect of crude extract and its solvent fractions up to 2 mg/plate toward Salmonella typhimurium TA 98 with or without S-9 mix metabolic activations. On the contrary, the crude extract showed an inhibitory activity against the mutagenicity of CSC in the presence of S-9 mix metabolic activation. Diethyl ether layer among five solvent fractions showed the highest inhibitory activity. The inhibitory activity of diethyl ether fraction was also increased in a dose-dependent manner and the inhibitory rate was about 97.7% at the concentration of 1 mg/plate. In this study, we conclude that crude extract of C. zawadskii itself is potentially safe for mutagenicity, and the diethyl ether fraction has an inhibitory effect against the mutagenicity of CSC.

Phosphorylation of p53 at threonine 155 is required for Jab1-mediated nuclear export of p53

  • Lee, Eun-Woo;Oh, Wonkyung;Song, Hosung Paul;Kim, Won Kon
    • BMB Reports
    • /
    • v.50 no.7
    • /
    • pp.373-378
    • /
    • 2017
  • The Jun activation-domain binding protein 1 (Jab1) induces p53 nuclear export and cytoplasmic degradation, but the underlying mechanism is poorly understood. Here, we show that phosphorylation at the threonine 155 residue is essential for Jab1-mediated p53 nuclear export. Jab1 stimulated phosphorylation of p53 at T155 was inhibited by curcumin, an inhibitor of COP9 signalosome (CSN)-associated kinases. The T155E mutant, which mimics phosphorylated p53, exhibited spontaneous cytoplasmic localization in the absence of Jab1. This process was prevented by leptinomycin B (LMB), but not by curcumin. The substitution of threonine 155 for valine (T155V) abrogated Jab1-mediated p53 nuclear export, indicating that phosphorylation at this site is essential for Jab1-mediated regulation of p53. Although T155E can be localized in the cytoplasm in the absence of Mdm2, the translocation of T155E was significantly enhanced by ectopic Hdm2 expression. Our data suggests that Jab1-mediated phosphorylation of p53 at Thr155 residue mediates nuclear export of p53.

Identification of Benzidine Metabolites in Rats by Gas Chromatography/Mass Selective Detector and its Toxicity in vitro (Gas-Chromatography/Mass Selective Detector를 사용하여 쥐의 뇨시료 중 benzidine 대사체의 확인 및 in vitro 독성)

  • 류재천;권오승
    • YAKHAK HOEJI
    • /
    • v.44 no.5
    • /
    • pp.384-390
    • /
    • 2000
  • Metabolism study of the dye, benzidine, was performed by gas chromatography-mass selective detector (GC/MSD) in the urine of rats orally administered 100 mg/kg benzidine. Urine samples were collected in metabolic cages for 0-24, 24-48, and 48-72 hrs. Ten ml of the urine was extracted with XAD-2 resin and the XAD-2 column was eluted with methanol. After evaporation, benzidine and its metabolites were extracted with diethyl ether (for non-conjugated fraction). For conjugated metabolites, $\beta$-glucu-ronidase was added to the aqueous layer that was incubated for 1 hr at 5$0^{\circ}C$ and the aqueous layer was extracted as in non-conjugated fraction. Aliquot of trimethylsilylated derivatives was applied to the GC/MSD. The mutagenicity of benzidine and its acetylated metabolites was tested by histidine/reversion assay. Five metabolites observed and confirmed either by electron impact and chemical ionization modes of the GC/MSD, or authentic compounds were monoacetyl-, diacetyl-, hydroxyacetyl-, hydroxydiacetyl-, and hydroxy-benzidine. Monoacetyl-benzidine was more potent than benzidine in histidine/reversion assay. This data indicates that monoacetylation of benzidine may be one of the metabolites produced in metabolic activation process.

  • PDF

Tschimganidine reduces lipid accumulation through AMPK activation and alleviates high-fat diet-induced metabolic diseases

  • Min-Seon Hwang;Jung-Hwan Baek;Jun-Kyu Song;In Hye Lee;Kyung-Hee Chun
    • BMB Reports
    • /
    • v.56 no.4
    • /
    • pp.246-251
    • /
    • 2023
  • Obesity increases the risk of mortality and morbidity because it results in hypertension, heart disease, and type 2 diabetes. Therefore, there is an urgent need for pharmacotherapeutic drugs to treat obesity. We performed a screening assay using natural products with anti-adipogenic properties in 3T3-L1 cells and determined that tschimganidine, a terpenoid from the Umbelliferae family, inhibited adipogenesis. To evaluate the anti-obesity effects of tschimganidine in vivo. Mice were fed either a normal chow diet (NFD) or a high-fat chow diet (HFD) with or without tschimganidine for 12 weeks. Treatment with tschimganidine decreased lipid accumulation and adipogenesis, accompanied by reduced expression of adipogenesis and lipid accumulation-related factors. Tschimganidine significantly increased the phosphorylation of AMP-activated protein kinase (AMPK) and decreased that of AKT. Depletion of AMPK relieved the reduction in lipid accumulation resulting from tschimganidine treatment. Moreover, tschimganidine administration drastically reduced the weight and size of both gonadal white adipose tissue (WAT) and blood glucose levels in high-fat diet-induced obese mice. We suggest that tschimganidine is a potent anti-obesity agent, which impedes adipogenesis and improves glucose homeostasis. Tschimganidine can then be evaluated for clinical application as a therapeutic agent.