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Mercuric sulfide (HgS) is a major component of cinnabar, which has been used as a sedative drug in China for more than 2000 years. Because its toxicological effects are still unclear, we attempted to verify the toxic effects of HgS, focused on liver and immune organs such as the spleen and thymus. Male ICR mice were administered HgS (0.02, 0.2, 2.0 g/kg/day) by gavage for 4 weeks. During the administration period, HgS-treated mice did not reveal overt signs of clinical toxicity. HgS had no significant effect on body weight, food consumption, water consumption, and organ weights. In spite of its known insolubility, HgS was absorbed by the gastrointestinal tract and accumulated in the liver, spleen and thymus in a dose-dependent manner. In the biochemical and histological examination, HgS did not cause hepatotoxicity. However, HgS significantly increased both CD8+ T lymphocytes and CD4+CD8+ lymphocyte populations in the spleen without changing in the thymus. In the histological evaluation, HgS induced enlargement with marked hyperplasia and increase of lymphoid follicles in the spleen. In addition, HgS induced the gene expression of pro-inflammatory cytokines in the spleen and thymus. Our results suggest that insoluble HgS was absorbed by the gastrointestinal tract, accumulated in the spleen and thymus, and thus could affect immune systems. [ABSTRACT FROM AUTHOR]

This study examined the dose-linearity pharmacokinetics of bisphenol A, a U.S. Environmental Protection Agency (EPA) classified endocrine disruptor, in rats following iv administration. Upon iv injection of 0.2, 0.5, 1, or 2 mg/kg, serum levels of bisphenol A declined biexponentially, with mean initial distribution and elimination half-life ranges of 4–8.2 min and 38.6–62.2 min, respectively. There were no significant alterations in the systemic clearance rate (mean range 90.1–123.6 ml/min/kg) and the steady-state volume of distribution (mean range 4.6–6.0 L/kg) as a function of the administered dose. In addition, the area under the serum concentration–time curve linearly rose as the dose was increased. In a second study, bisphenol A was given by simultaneous iv bolus injection plus infusion to steady state, and levels were measured in serum and various organs. When expressed in concentration terms (e.g., amount accumulated per gram organ weight), bisphenol A was found predominantly in the lung, followed by kidneys, thyroid, stomach, heart, spleen, testes, liver, and brain. Ratios of the organ to serum bisphenol A concentrations exceeded unity for all the organs examined (ratio range 2.0– 5.8) except for brain (ratio 0.75). Given the high systemic clearance and short elimination half-life, bisphenol A is unlikely to accumulate significantly in the rat. [ABSTRACT FROM AUTHOR]

In this study, we demonstrated the in vitro and in vivo formation of carcinogen–lipid adduct and its correlation with DNA or protein adducts. The lipids from serum or hepatocyte membranes of Sprague–Dawley rats, human serum and standard major lipids were in vitro reacted with benzo[a]pyrene (B[a]P) and B[a]P metabolites. 7,8-Dihydroxy-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene(BPDE-I), an ultimate carcinogenic form of B[a]P, was covalently bound to triglyceride (TG). BPDE-I–TG adducts isolated by thin-layer chromatography (TLC) were further detected by high-performance liquid chromatography. TGs, including triolein, tripalmitin and tristearin, showed positive reactions with BPDE-I. However, cholesterol, phospholipids (phosphatidylcholine, phosphatidyl-ethanolamine, phosphatidyl-inositol and sphingomyelin) and non-esterified fatty acids (palmitic acid, oleic acid, linoleic acid and stearic acid) did not react with BPDE-I. In addition, other B[a]P metabolites (B[a]P-phenols and -diols) did not react with TG. TG appeared to be the most reactive lipid yet studied with respect to its ability to form an adduct with BPDE-I. There was a clear-cut dose-related formation of [1,3-3H]BPDE-I–lipid adducts in vitro between TG and [1,3-3H]BPDE-I. In an animal study, BPDE-I–TG was also formed in the serum of rats orally treated with B[a]P (25 mg/rat). Also, obvious correlations between [3H]B[a]P related-biomolecule adducts (DNA or protein) or lipid damage and the BPDE-I–TG adducts were obtained in various tissues of mice i.p. treated with [3H]B[a]P. These data suggest that TG can form an adduct with BPDE-I, as do other macromolecules (DNA, RNA and protein). Therefore, a carcinogen–lipid adduct would be a useful biomarker for chemical carcinogenesis research and cancer risk assessment. [ABSTRACT FROM PUBLISHER]

An abstract of the article "Integration and Biodistribution Studies of Retroviral Vector in Mouse Gonad Tissues," by Gyu Seek Rhee, Ji hyun Seok, Soon Sun Kim, Seung Jun Kwack, Bo Ra Kim, Rhee Da Lee, Soo Yeong Chae, Young Hyuk Won, Seung Shin Yu and Dae Hyun Cho is presented.

N-nitrosamines and their precursors found in cosmetics may be carcinogenic in humans. Thus the aim of this study was to carry out risk assessment for N-nitrosamines (N-nitrosodiethanolamine [NDELA], N-nitrosodiethylamine [NDEA]) and amines (triethanolamine [TEA], diethanolamine [DEA]) levels in cosmetics determined using validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) procedures. NDELA and NDEA concentrations were present at levels of "not detected" (N.D.) to 596.5 μg/kg and N.D. to 40.9 μg/kg, respectively. TEA and DEA concentrations ranged from N.D. to 860 μg/kg and N.D. to 26.22 μg/kg, respectively. The nitrite concentration (3-2250 mg/l), number of nitrosating agents to a maximum 5, and pH (3.93-10.09) were also assessed. The impact of N-nitrosamine formation on the levels of TEA, DEA, nitrite, and other nitrosating agents was also examined. N-nitrosamine concentrations correlated with the number of nitrosating agents and nitrite concentrations. Data demonstrated that higher nitrite concentrations and a greater number of nitrosating agents increased NDELA and NDEA yields. Further, the presence of TEA and DEA exerted a significant influence on N-nitrosamine formation. Risk assessments, including the margin of exposure (MOE) and lifetime cancer risk (LCR) for N-nitrosamines and margin of safety (MOS) for amines, were calculated using product type, use pattern, and concentrations. Exposure to maximum amounts of NDELA and NDEA resulted in MOE > 10,000 (based upon the benchmark dose lower confidence limit 10%) and LCR <1 × 10 -5 , respectively. In addition, TEA and DEA concentrations in cosmetic samples resulted in MOS values >100. Therefore, no apparent safety concerns were associated with cosmetic products containing NDELA, NDEA, TEA, and DEA in this study. However, since amines and nitrosating agents produce carcinogenic nitrosamines, their use in cosmetics needs to be minimized to levels as low as technically feasible.

A metabolomics approach using proton nuclear magnetic resonance (NMR) was applied to investigate metabolic alterations following adriamycin (ADR) treatment for gastric adenocarcinoma. After BALB/c-nu/nu mice were implanted with human gastric adenocarcinoma, ADR (1 or 3 mg kg(-1) per day) was intraperitoneally administered for 5 days. Urine was collected on days 2 and 5 and analyzed by NMR. The levels of trimethylamine oxide (TMAO, ×0.3), hippurate (×0.3) and taurine (×0.6) decreased significantly (P < 0.05), whereas the levels of 3-indoxylsulfate (×12.6), trigonelline (×1.5), citrate (×2.5), trimethylamine (TMA, ×2.0) and 2-oxoglutarate (×2.3) increased significantly (P < 0.05) in the tumor model. After ADR treatment, TMAO, hippuarte and taurine were increased significantly on day 5 compared with those of the tumor model. The levels of 2-oxoglutarate, 3-indoxylsulfate, trigonelline, TMA and citrate, which increased in the tumor model, significantly decreased to those of normal control by ADR treatment. Furthermore, the ratio between TMA and TMAO was dramatically altered in both tumor and ADR-treated groups. Overall, metabolites such as TMAO, TMA, 3-indoxylsulfate, hippurate, trigonelline, citrate and 2-oxoglutarate related to the tricarboxylic acid (TCA) cycle might be considered as therapeutic targets to potentiate the efficacy of ADR. Thus, these results suggest that the metabolomics analysis of tumor response to ADR treatment may be applicable for demonstrating the efficacy of anticancer agent, ADR and treatment adaptation., (Copyright © 2012 John Wiley & Sons, Ltd.)

Seven known triterpene glycosides, 23-O-acetylshengmanol 3-O-α-L-arabinopyranoside (1), 23-O-acetylshengmanol 3-O-β-D-xylopyranoside (2), 24-epi-24-O-acetylhydroshengmanol 3-O-β-D-xylopyranoside (3), cimiaceroside B (4), (23R,24S)-cimigenol 3-O-β-D-xylopyranoside (5), (23R,24R)-25-O-acetylcimigenol 3-O-β-D-xylopyranoside (6) and (23R,24S)-25-O-anhydrocimigenol 3-O-β-D-xylopyranoside (7) were isolated from the rhizomes of Cimicifuga heracleifolia. Their chemical structures were determined on the basis of spectroscopic analyses including 2D NMR. All isolates were investigated for their inhibitory effects on the classical pathway of the complement system. Among them, compound 6 showed strong inhibitory activity with an IC₅₀ value of 7.7 µM while compound 3 was moderately active with an IC₅₀ value of 195.6 µM., (Georg Thieme Verlag KG Stuttgart · New York.)

Two new lignans, (2 R,3 R)-2 β-(4''-hydroxy-3''-methoxybenzyl)-3 α-(4'-hydroxy-3'-methoxybenzyl)-γ-butyrolactone 2-O-( β-D-glucopyranoside) (1) and (1 S,2 R,3 S)-dimethyl-1,2,3,4-tetrahydro-3,6,7-trihydroxy-1-(3',4'-dihydroxyphenyl)naphthalene-2,3-dicarboxylate (2) together with nine known compounds (3-11) were isolated from the ethyl acetate fraction of the roots of Pulsatilla koreana. Their chemical structures were established based on physicochemical and spectroscopic data analyses. All isolates were investigated for their inhibition effects against the classical pathway of the complement system. Among them, compound 6 showed significant inhibitory activity with an IC (50) value of 75.9 µM, compounds 8 and 9 had moderate effects with IC (50) values of 182.2 and 166.5 µM, respectively., (© Georg Thieme Verlag KG Stuttgart · New York.)

Metabonomic investigation of doxorubicin (adriamycin) was carried out in male Sprague-Dawley rats using high-resolution (1)H nuclear magnetic resonance (NMR) spectroscopy coupled with multivariate statistics. Urine samples (d -1 to 7) from rats treated with doxorubicin at two dose levels (5 or 15 mg/kg body weight) were collected at each time point and doxorubicin-induced biomarkers were examined. Of metabolites, early elevated biochemical changes were observed in trimethylamine N-oxide (TMAO) levels suggesting renal dysfunction. Perturbation in TMAO was maximal in the low-dose group at 48 h post dose (p.d.) and returned to control at 168 h p.d., indicating recovery from renal toxicity induced by doxorubicin. After doxorubicin administration, the high-dose group was divided into low and high responders at 48 h and further divided into high, moderate, and no recovery animals at 96 h, indicating individual susceptible response to drug-induced toxicity. Urinary increases in glucose, lactate, alanine, and valine suggested progression of renal damage resulting in glycosuria, lactic aciduria, and aminoaciduria up to 168 h in the high-dose group. Urinary elevation of creatine and phenylacetylglycine (PAG) together with reduction of N-methylnicotinic acid (NMNA) and hippurate levels was suggestive of liver injury in the high-dose group. Impairment of energy metabolism was also indicated by decreased levels of tricarboxylic acid cycle intermediates in urine of rats treated with high-dose doxorubicin. This study highlights the applicability of NMR-based metabonomics with multivariate statistics for monitoring biomarkers produced by doxorubicin treatments.

Each specific protein has an individual gene encoding it, and a foreign gene introduced to a plant can be used to synthesize a new protein. The identification of potential reproductive and developmental toxicity from novel proteins produced by genetically modified (GM) crops is a difficult task. A science-based risk assessment is needed in order to use GM crops as a conventional foodstuff. In this study, the specific characteristics of GM food and low-level chronic exposure were examined using a five-generation animal study. In each generation, rats were fed a solid pellet containing 5% GM potato and non-GM potato for 10 wk prior to mating in order to assess the potential reproductive and developmental toxic effects. In the multigeneration animal study, there were no GM potato-related changes in body weight, food consumption, reproductive performance, and organ weight. Polymerase chain reaction (PCR) was carried out using extracted genomic DNA to examine the possibility of gene persistence in the organ tissues after a long-term exposure to low levels of GM feed. In each generation, the gene responsible for bar was not found in any of the reproductive organs of the GM potato-treated male and female rats, and the litter-related indexes did not show any genetically modified organism (GMO)-related changes. The results suggest that genetically modified crops have no adverse effects on the multigeneration reproductive-developmental ability.

Alcohol drinking during pregnancy results in abnormal fetal development, including fetal alcohol syndrome (FAS) in humans and experimental animals. FAS is characterized by two major effects, including central nervous system (CNS) dysfunction and multiple anomalies recognizable mainly as a typical face. However, the mechanisms of alcohol-induced embryotoxicity have not been clearly demonstrated. The aim of the present study was to investigate the possible mechanisms underlying ethanol-induced FAS in the developing embryo. First, ethanol-induced developmental abnormalities were investigated in vitro. Postimplantation embryos at gestation day (GD) 9.5 were cultured for 48 h and observed for morphological changes. Ethanol-mediated changes in proteins regulated apoptosis (p53 and bcl-2), antioxidant (vitamin E and catalase) activities, generation of reactive oxygen species (ROS), and oxidative DNA damage shown as 8-hydroxy-2'-deoxyguanosine (8-OHdG) were measured in embryonic midbrain cells. Alcohol or acetaldehyde significantly induced cytotoxicity in cultured rat embryonic midbrain cells. The levels of p53, bcl-2, and 8-OHdG were concomitantly changed by alcohol and acetaldehyde treatment in midbrain cells. Injured cells induced by ROS were increased by alcohol or acetaldehyde treatment in midbrain cells. Cotreatment with alcohol or acetaldehyde and catalase decreased cytotoxicity in midbrain cells. In postimplantation embryo culture, alcohol or acetaldehyde-treated embryos showed retardation of embryonic growth and development in a concentration-dependent manner. These results indicate that alcohol and its metabolite acetaldehyde induce fetal developmental abnormalities by disrupting cellular differentiation and growth. Data demonstrate that some antioxidants can partially protect against the alcohol-induced embryonic developmental toxicity.

Tetramethrin, a synthetic pyrethroid insecticide, is used globally for agriculture, and thus potential environmental exposure to tetramethrin is a concern. Environmental chemicals that are hormonally active (particularly estrogen or androgen) may adversely affect the reproductive and endocrine systems. However, little is known about the estrogenic and androgenic activities of tetramethrin. In this study, uterine CaBP-9k gene expression assay and a uterotrophic assay were conducted for estrogenic activity assessment of tetramethrin, and a Hershberger assay was conducted for androgenic activity. Estrogen receptor (ERalpha and ERbeta) protein levels were also measured in tetramethrin-treated rat uteri. Northern blot analysis showed reduction in uterine CaBP-9k mRNA levels in response to tetramethrin, as well as when rats were given both tetramethrin and 17beta-estradiol (E2). In the uterotrophic assay using 18-d-old female Sprague-Dawley rats, subcutaneous treatment with tetramethrin (5 to 800 mg/kg/day) for 3 d led to a statistically significant decrease in absolute and relative uterine wet weights at all doses tested. Moreover, tetramethrin blocked the effect of E2 on uterine weights. In addition, tetramethrin reduced absolute and relative vaginal wet weights, and also inhibited the increases of vaginal weights produced by E2. Tetramethrin showed no androgenic on antiandrogenic activities in the Hershberger assay. These results suggest that tetramethrin might exert endocrine-disrupting effects on female rats through antiestrogenic action.

The mutagenic potential of the extracted components of Gryllus bimaculatus, a species of cricket, was evaluated using short-term genotoxicity tests including the Ames, chromosome aberration, and micronuclei tests. In a Salmonella typhimurium assay, G. bimaculatus extract did not produce any mutagenic response in the absence or presence of S9 mix with TA98, TA100, TA1535, and TA1537. Chromosome aberration testing showed that G. bimaculatus had no significant effect on Chinese hamster ovary (CHO) cells. In the mouse micronucleus test, no significant alteration in occurrence of micronucleated polychromatic erythrocytes was observed in ICR male mice intraperitoneally administered with G. bimaculatus extract at doses of 15, 150, or 1500 mg/kg. These results indicate that G. bimaculatus extract exerts no mutagenic effect in these in vitro and in vivo systems.

Pyrethroid insecticides exhibited a weak estrogenic activity by stimulation of MCF-7 cell proliferation and induction of alkaline phosphatase (AlkP) enzyme activity in cultured Ishikawa cells. Previously it was reported that fenvalerate and permethrin significantly inhibited the 17beta-estradiol-induced MCF-7 BUS cell proliferation. Although certain pyrethroid insecticides exert estrogenic or antiestrogenic activities, it is not clear whether pyrethroid insecticides act as progesterone agonists or antagonists. Therefore, the aim of this study was to evaluate the effects of fenvalerate and permethrin on AlkP activity as a progesterone-specific response in T47D cells. In the present study, the stimulation of AlkP activity was concentration dependent with addition of progesterone, and maximum activity was observed at concentration of 1 x 10(-8) M. Both fenvalerate (1 x 10(-6) M) and permethrin (1 x 10(-6) M) did not stimulate the AlkP activity, but progesterone (1 x 10(-8) M)-induced AlkP activity was significantly inhibited at 1 x 10(-6) M concentration of fenvalerate and permethrin, respectively. Progesterone receptor (PR) levels in cytosolic protein of T47D cells were studied to determine the relationship between cellular PR expression and AlkP activity. Similar to AlkP activity, progesterone (1 x 10(-8) M) significantly increased PR protein levels compared to control. However, PR protein levels were not affected in T47D cells cultured with fenvalerate and permethrin alone, whereas fenvalerate and permethrin significantly decreased progesterone-induced PR protein levels. Our data indicate that fenvalerate and permethrin exhibit antiprogestagenic activity in T47D human breast cancer cells.

Cytochrome P-450 and glutathione S-transferase (GST) activities were investigated in stomach tumor and tumor-adjacent tissues of patients (n = 211) with gastric adenocarcinoma, and in the stomach tissues of unaffected individuals (normal tissues, n = 113). A significant reduction in total cytochrome P-450 activity was observed in tumor and tumor-adjacent tissues versus normal stomach. In all cases, cytochrome P-450 activity was significantly higher in males than in females. In the case of smokers, cytochrome P-450 activity was 1.8-fold higher in tumor-adjacent than in corresponding tumor tissues, but no difference was observed in nonsmokers. Patients had significantly lower GST activity in tumor and tumor-adjacent tissues compared to normal tissues. Smokers showed lower GST activity in both tumor and tumor-adjacent tissues compared to nonsmokers. In addition, GST activity was significantly lower in tissues positive for Helicobacter pylori infection than in H. pylori-negative tissues. However, the frequency of H. pylori infection was higher in tumor-adjacent (69%) than in tumor (45%) or normal tissues (44%). Our data suggest that diminished GST enzymes activity and increased cytochrome P-450 activity in normal and tumor-adjacent tissues might be due to the direct effect of the H. pylori infection and cigarette smoking, respectively. Data indicate that alterations in the activities of cytochrome P450 and GST may in part be associated with an increased risk for gastric cancer.

This study was conducted in order to obtain information on the association between age and oxidative DNA damage and benzo[a]pyrene diolepoxide-I (BPDE-I)-DNA adduct levels in the stomach tissues of normal subjects (n = 113). Subjects ranged from 17 to 75 yr. The levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a biomarker of oxidative DNA damage, were measured by high-performance liquid chromatography-electrochemical detector (HPLC-ECD). BPDE-I-DNA adduct levels were quantitatively measured by enzyme-linked immunosorbent assay (ELISA) using the monoclonal antibody 8E11. Increase in 8-OHdG levels was observed in subjects from 31 to 60 yr of age. Higher levels of 8-OHdG were observed in the stomach tissues of those in the 51-60 yr old group. Although Helicobacter. Pylori-positive group subjects had higher 8-OHdG levels than those in the H. pylori-negative group, no age-related changes in 8-OHdG levels were observed in these groups. The levels of BPDE-I-DNA adduct also markedly increased with age. Higher levels of BPDE-I-DNA adduct were observed in subjects aged 61-70 yr, but this difference was not significant from other age groups. These results provide evidence that there is a progressive age-dependent accumulation of oxidative DNA damage and of BPDE-I-DNA adducts in human stomach tissues. It is possible that such damage contributes to the known increased incidence of gastric tumor with aging.

The mutagenic potential Isaria sinclairii, a traditional Chinese medicine composed of the fruiting bodies of I. sinclairii and its parasitic host larva, was evaluated using short-term genotoxicity tests, namely, the Ames test, chromosome aberration (CA), and micronuclei (MN) tests. In a Salmonella typhimurium assay, I. sinclairii extract (ISE) did not produce any mutagenic response in the absence or presence of 59 mix with TA98, TA100, TA1535, and TA1537. In the chromosome aberration (CA) test, ISE induced no significant effect on Chinese hamster ovary (CHO) cells compared with control. In the MN test, no significant change in the occurrence of micronucleated polychromatic erythrocytes was observed in male ICR mice intraperitoneally administered ISE at doses of 15, 150, or 1500 mg/kg. These results indicate that ISE has no mutagenic potential in these in vitro and in vivo systems.

Alcohol consumption during pregnancy results in morphological abnormalities in the fetuses of humans and experimental animals, and is referred to as fetal alcohol syndrome (FAS). However, the molecular mechanism underlying FAS has not been completely elucidated. The aim of the present study was to investigate the potential molecular mechanisms of ethanol-induced FAS in the developing embryo and fetus. cDNA microarray analysis was used to screen for altered gene profiles. Ethanol at a teratogenic dosage (3.8 g/kg, twice a day) was administered intraperitoneally to pregnant C57Bl/6J mice from gestation day (GD) 6 to 8. Morphologic observations showed excessive malformations of the craniofacial regions (reduction of the face, the absence of eyes, nose, jaw, and mandible, underdevelopment of vibrissae areas, cleft lip, and palate) in ethanol-exposed embryos (GD 10) and fetusus (GD 15). cDNA microarray analysis showed alterations in several gene profiles, including the "palate, lung, and nasal epithelium clone (plunc), "neurofilament, " and "pale ear. " Of these genes, the expressions of plunc were confirmed by reverse-transcription polymerase chain reaction (RT-PCR) and whole-mount in situ hybridization. The plunc was highly expressed in the craniofacial region, specifically in upper airways and nasopharyngeal epithelium. RT-PCR analysis revealed that normal plunc mRNA expression levels were present in GD 15 fetuses, but not in GD 10 embryos. Interestingly, ethanol significantly downregulated the plunc expression in GD 15 fetuses. Our results suggest that ethanol-induced FAS is due in part to the downregulation of plunc expression in the fetus, and this gene may be a candidate biological marker for FAS.