Many agrochemicals have one or more chiral centers and are used as racemic mixtures. Monitoring the stereoselective degradation and/or transformation of agrochemical enantiomers is an important target in environmental chemistry. For chiral analysis, capillary electrophoresis has advantages over other chromatographic methods, in resolution, cost performance and simplicity. This review summarizes chiral separation techniques of real samples of agrochemicals using capillary electrophoresis.
Recently we found that extracts from ancient rice brans, especially those from black rice bran, possess strong scavenging activities for reactive oxygen species (ROS). In this study, we examined the origin of the ROS-scavenging activities in the black rice bran extracts, and identified candidate scavengers such as cyanidin-3-glucoside (Cy-3-glu) and cyanidin. Although ferulic acid is known to be an antioxidative component of bran in currently available common white rice varieties, it was not found in the black rice bran extracts. The ROS-scavenging activities of Cy-3-glu and cyanidin, which were identified in this study, were examined using the ESR-spin trap method and in terms of protective activity against effects of ultraviolet (UVB) irradiation on an epidermal cell line (HaCaT cell). These anthocyanin compounds were found to possess both strong ROS-scavenging activities and to suppress cell-damaging effects of UVB, indicating that both Cy-3-glu and cyanidin are the active components involved in the antioxidative activity of black rice bran extracts.
Epidemiologic studies have suggested a close correlation between arsenic exposure and cardiovascular disease. In mechanism studies of heart disease and arsenic exposure, blood vessels, vascular smooth muscle cells, and endothelial cells of the artery have long been thought to be the primary targets in arsenic exposure but there are only a few studies on cardiomyocytes. In this study, to predict more diverse responses of cardiomyocytes to arsenic exposure in the development of heart failure, gene expression profiles of cultured rat cardiomyocytes (H9C2 cell line) were evaluated using the rat whole-genome microarray when a subcytotoxic level of arsenic trioxide was treated. After 24 hr of arsenic 0.5 ppm exposure (As2O3 was used), 405 genes were up-regulated including heme oxygenase-1, and 499 genes were down-regulated including fibroblast growth factor. With the subcytotoxic dose of As2O3, oxidative stress was generated without cell death, and the transcription of stress-related genes such as heme oxygenase-1, glutathione S-transferase, metallothionein, and catalase were significantly increased. Direct measurement of reactive oxygen species using fluorescent dye showed that arsenic caused oxidative stress at the subcytotoxic level. Although no direct comparison was made among different types of cells in this study, it appears that arsenic can cause physiologic adverse reactions at a relatively low level in cardiomyocytes and that cardiomyocytes are also one of the vulnerable targets of heart failure by arsenic compounds.
When 56 selected environmental chemicals were tested for the androgenic activity to Yeast Two-hybrid and reporter gene assay in the presence of 5α-dihydrotestosterone (DHT), the activity was inhibited by some of the chemicals including N-nitrosodiphenylamine (NDPA), a novel anti-androgenic compound, and one of suspected carcinogenic N-nitrosocompounds (NOCs) commonly used as material of rubber and plastic goods. We further examined 15 NOCs for anti-androgenic activity, and found that N-nitrosodibenzylamine (NDBzA) and N-nitrosodicyclohexylamine (NDCHA) as well as NDPA inhibited the activity of DHT in a dose-dependent manner. These compounds showed the competitive binding to androgen receptor (AR) against DHT and decreased the level of AR protein. Furthermore, 3 NOCs down-regulated the prostate specific antigen (PSA) at the transcriptional level in LNCaP cells. These results suggest that some NOCs antagonized the androgenic effect of DHT in the same manner as the synthetic anti-androgen, flutamide (F).
Serum lipid level increases during hormonal transition before and after menopause. In Caucasians, changes in lipid level after menopause across apolipoprotein E (apo E) genotypes were studied. We investigated 159 Japanese healthy female workers (age range, 35-63). The apo E genotypes were determined by the polymerase chain reaction single-strand conformation polymorphisms method for the entire apo E-coding region. The low-density lipoprotein cholesterol (LDL-cholesterol) level significantly varied according to the apo E genotype, but not according to the menopausal status after adjusting for age and body mass index (p < 0.001). The effect of menopause on LDL-cholesterol level significantly varied depending on the apo E genotype (p < 0.05). Apo E2 [APOE, R158C] carriers in the senium period had a lower LDL-cholesterol level than those in the fertile period (81.5 ± 12.0 mg/dl vs. 122.3 ± 12.9 mg/dl). In contrast, apo E3 homozygotes in the senium period showed a higher LDL-cholesterol level than those in the fertile period (140.9 ± 7.0 mg/dl vs. 134.1 ± 6.1 mg/dl). The LDL-cholesterol levels of apo E4 [APOE, C112R] carriers were the similar for the two periods. These results indicate that the serum lipid control in perimenopausal women should be customized according to the apo E genotype for the promotion of women's health in Japan.
Although copper plays a critical role in the embryonic development and differentiation of mammals, the molecular mechanism(s) by which copper deficiency during development leads to embryonic defects has not been sufficiently investigated. In this study, we have focused on the roles of copper in neurogenesis, using mouse embryonal carcinoma P19 cells as a model of neuronal differentiation. In morphological and immunofluorescence studies, we observed that the retinoic acid (RA)-induced neuronal differentiation of P19 cells was suppressed in copper-deficient conditions using a non-permeable copper chelator, BCS. Consistent with this result, minimum amounts of the neuron-specific marker dopamine β-hydroxylase and choline acetyltransferase mRNA were induced in the copper-deficit P19 cells. Furthermore, copper deficiency in P19 cells could suppress the activation of RA receptor (RAR) target genes, such as RARβ2 and cellular retinol binding protein 1 and p21waf1/cip1, and RA response element-driven reporter expression by RA. Consequently, our results indicate that intracellular copper is involved in RAR-dependent transcription, which may contribute to explaining the defect of neuronal differentiation in copper-deficit P19 cells.
We have reported that erythrosine (ET), a xanthene dye, inhibited uridine 5-diphosphate (UDP)-glucuronosyltransferase 1A6 (UGT1A6). In order to clarify the structure-inhibition relationships of these xanthene dyes, the inhibitory effect of xanthene dye on human UGT1A6 activity was investigated, such as acid red (AR), ET, phloxine (PL), and rose bengal (RB). ET, PL, and RB strongly inhibited human UGT1A6 activity, with IC50 values = 0.05, 0.04, and 0.015 mM, respectively. Meanwhile, AR had almost no effect (IC50 value = 1.7 mM). ET, PL and RB have four halogen atoms on their xanthene backbone, unlike AR. Meanwhile, some contrast media with high halogens on those aromatic compounds, such as ioxaglic acid, iodixanol, meglumine iotalamate, and diatriazole sodium, did not inhibit human UGT1A6 activity. These results suggest that halogens enhance the inhibitory effect of xanthene dyes. In this study, it was proved that xanthene dyes had an inhibitory effect on human UGT1A6 activity by the combination of xanthene structure and halogens on its. Part of this inhibition by xanthene dyes depends the reaction of 1O2 originated on xanthene dyes by light irradiation, because the inhibition was prevented by 1O2 quenchers, such as NaN3 and histidine, and in the dark.
There is general agreement that soy isoflavones can be beneficial to health in adults. However, isoflavones are well known as endocrine-disrupting chemicals. The possibility that soy foods might adversely affect the reproductive system of mothers and infants should be considered. The aim of this study was to evaluate the adverse effects of a soy isoflavone mixture on rat dams and their offspring. The rat dams were fed diets containing the isoflavone mixture (commercial name: Soyact, aglycone type) at 0, 0.25, 0.5 and 1.0 g/kg as total isoflavones from pregnancy day 5 to postnatal day 13. We found that the dietary soy isoflavone mixture decreased the dam body weights in a dose-dependent manner and that the number of pups also tended to decrease. Genistein and daidzein were detected in the blood of the dams and the stomach contents of the suckling pups. The concentrations of daidzein were higher than those of genistein. We also found the transfer of isoflavones to the fetus. The reproductive output and fetus numbers were not significantly different in the isoflavone groups compared with the control group. The number of absorbed fetuses tended to increase though not significant. Our experiments suggested that soy isoflavones have the possibility of inducing adverse effects on endocrinic functions and others in animal studies at very high doses.
Arsenic effect was studied at two dosage levels (0.5 mg and 1 mg/kg) for 45 days in two regions of brain, viz., cerebral hemisphere (CH) and cerebellum (C) in adult mice. This study included the antioxidant profile namely superoxide dismutase (SOD), catalase, lipid peroxidation, reduced glutathione, ascorbic acid and total sulphydryl groups. Adenosine triphosphatase (ATPase), succinic dehydrogenase (SDH), phosphorylase together with glycogen and protein levels were also estimated as metabolic indices in the brain regions of mice. A notable decrease was detected in the activities of the enzymes and in the levels of other metabolites together with a significant increase in the lipid peroxidation, glycogen and inorganic arsenic levels after arsenic administration. Supplementation of vitamin A to the arsenic treated mice brought about no significant variation in these antioxidant and metabolic indices in comparison to that of control, revealing amelioration by vitamin A on arsenic exerted metabolic and neurotoxic effects in mice.
The growth-inhibitory effects of the brownish scale components of onion on tumor cells were studied with relating to their membrane activity. Quercetin, quercetin-4'-O-glucoside and two isomeric quercetin dimers (10 μM for each) isolated from the scale reduced the fluidity of tumor cell model membranes consisting of phospholipids and cholesterol more significantly than that of normal cell model membranes. In flavonoidal components, the membrane activity was greatest in the order of dimers, aglycone and glucoside. Quercetin and its dimers intensively acted on the membrane center rather than the membrane surface, while quercetin-4'-O-glucoside was relatively effective on the hydrophilic regions of membranes. Membrane-active flavonoids inhibited the growth of mouse myeloma cells at 10-100 μM with the same rank of order of potency as they rigidified liposomal membranes. Quercetin and its dimers rigidified cell membranes by acting on the hydrophobic inner regions simultaneously with inhibiting the cell growth, but not quercetin-4'-O-glucoside. Flavonoidal components in the brownish scale of onion have the potent anti-proliferative activity associated with the structure-specific rigidification of cell membranes, which is induced by the interaction with membrane lipid bilayers.
The effect of ammonia adsorption in aqueous solutions was examined for bamboo charcoal carbonized at 400, 700 and 1000°C, and activated carbon. Furthermore, the change of the ammonia adsorption in aqueous solutions was also examined by treatment of each sample with diluted sulfuric acid. Bamboo charcoal carbonized at 400°C and treated with diluted sulfuric acid was the most effective for removing ammonia from aqueous solutions. Although the ammonia adsorption of the bamboo charcoal carbonized at 400°C in gas phase hardly changed by the treatment with diluted sulfuric acid, that in aqueous solutions significantly increased by the treatment.
An enriched stable isotope is recognized as a label because of its high abundance relative to the corresponding endogenous natural abundance isotope in hosts, and hence is a relative label. Here, lowering the corresponding endogenous natural abundance element, multiple enriched stable isotopes were used as absolute labels for each. Thus, host animals were depleted of natural abundance stable isotopes by feeding a single enriched isotope, followed by administration of multiple precursors labeled with different homo-elemental stable isotopes. Metabolites of each labeled precursor were traced and speciated simultaneously by HPLC-inductively coupled argon plasma-mass spectrometry without interference from endogenous natural abundance isotopes. In the present experiments, rats with a single stable isotope (82Se) were administered with 76Se-selenite and 77Se-selenomethionine simultaneously. The metabolites of 76Se and 77Se were speciated simultaneously as absolute labels, and independently from the endogenous selenium. The advantages of multiple absolute labeling coupled with simultaneous speciation, and general applications to metallomics of biometals and other wider applications, are proposed and discussed.
The ethanolic extract of Daucus carota seeds (DCE) was investigated for anti-inflammatory and analgesic activity at the doses [per oral (p.o.)] of 100, 200 and 400 mg/kg body weight. For evaluation of inflammation carrageenan-, histamine- and serotonin-induced paw edema served as acute models and formaldehyde-induced arthritis served as a chronic model in rats. The acetic acid-induced writhing response and formalin-induced paw licking time in the early and late phases of mice were used to assess analgesic activity. The higher doses of DCE (200 and 400 mg/kg, p.o.) were inhibiting carrageenan, histamine and serotonin-induced paw edema as well as formaldehyde-induced arthritis successfully. In addition, DCE (200 and 400 mg/kg, p.o.) significantly attenuated the writhing responses induced by an intraperitoneal injection of acetic acid and late phase of pain response induced by an subplantar injection of formalin in mice.
The bee pollen Cistus ladaniferus (C. ladaniferus) extract has an anabolic effect on bone metabolism. The effects of the fractionated extracts obtained from bee pollen on bone calcium content and osteoclast-like cell formation in vitro were investigated. Rat femoral-diaphyseal and -metaphyseal tissues were cultured for 48 hr in a medium containing either vehicle or a water-solubilized extract with the membrane fractions obtained from bee pollen. The active component of bee pollen in increasing calcium content in diaphyseal tissues was seen in the fraction of molecular weight (MW) of less than 1000, and it was not observed in fractions of greater than MW 1000. Culture with the fractionated bee pollen extract (25 or 50 μg/ml of medium) of less than MW 1000 caused a significant increase in calcium content in the diaphyseal or metaphyseal tissues. The parathyroid hormone (PTH; 10-6 M)-induced decrease in diaphyseal calcium content was significantly prevented in the presence of the fractionated bee pollen extracts (10 μg/ml) of less than MW 1000 or greater than MW 1000. Mouse marrow cells were cultured for 7 days in a medium containing PTH (10-6 M) in the presence or absence of the fractionated bee pollen extract (10 or 50 μg/ml). The PTH-induced increase in osteoclast-like cell formation was markedly suppressed in the presence of extracts of less than MW 1000 as compared with that in the presence of fractions of greater than MW 1000. The effects of the fractionated bee pollen extracts of less than MW 1000 in increasing diaphyseal calcium content and in inhibiting PTH-induced osteoclastic cell formation were significantly decreased upon heat treatment for 20 and 60 min at 80°C. This study demonstrates that the active component of bee pollen C. ladaniferus extract, which stimulates bone formation and inhibits osteoclastic bone resorption, is the fraction with MW less than 1000.
trans-Stilbene exhibits estrogenic activity in an estrogen reporter assay after metabolic activation. In this study, uterotrophic assay was conducted using ovariectomized B6C3F1/Crj female mice treated with trans-stilbene, trans-4-hydroxystilbene, trans-4,4'-dihydroxystilbene and diethylstilbestrol. Administration of trans-4-hydroxystilbene, trans-4,4'-dihydroxystilbene and diethylstilbestrol elicited increases in absolute and relative uterus weight. Furthermore, the uterine response caused by the hydroxylated stilbenes was accompanied with an increase in the thickness of epithelial cell layers. trans-Stilbene itself also showed estrogenic activity, affecting uterine weight and causing histological changes of the uterus. This suggests that trans-stilbene is activated to hydroxylated metabolites to exhibit its estrogenic activity. Indeed, trans-hydroxystilbenes were detected in the urine and feces of mice dosed with trans-stilbene. The effect of stilbene derivatives on testis in newborn B6C3F1/Crj mouse was examined. Administration of diethylstilbestrol slightly decreased the testis weight and atrophy of seminiferous tubules. However, trans-stilbene and trans-4-hydroxystilbene affected neither testis weight nor the histological appearance of the testis.
Nine halogenated anilines, consisting of di- and tri-substituted fluoro-, chloro-, and bromoanilines, were subjected to analysis of their cytochrome P450 (CYP) 2E1/2A6-selective inhibitory effects on metabolic activation of dimetylnitrosamine (DMN) in human liver microsomes. Inhibitory activities (IC50) of these anilines on human recombinant CYP2E1 ranged from 8.0 to 549 μM. However, most of these anilines showed no remarkable inhibition of CYP1A2, while their IC50 values on CYP2A6 ranged from 2.9 to 232 μM. The CYP2E1 selectivity of these anilines in terms of the ratio of the IC50 values of these anilines on CYP2A6 to those on CYP2E1, ranged from 0.1- to 5.2-fold. Their CYP2E1 selectivity decreased in the following order: 3,4,5-trifluoroaniline (3,4,5-triF-A) > 3,5-diF-A >> 3,5-dichloroaniline (3,5-diCl-A) > 3,4-diCl-A > 2,6-diCl-A > 2,3,4-trichloroaniline (2,3,4-triCl-A) > 2,4,6-triCl-A > 2,6-dibromoaniline (2,6-diBr-A) > 3,4,5-triCl-A. The inhibitory effects of these anilines on metabolic activation of DMN were analyzed using human liver microsomes. The IC50 values of these anilines on demethylation metabolism of DMN correlated with those of these anilines on CYP2E1. These results suggest that these halogenated anilines may be useful as indicators of CYP-selectivity involved in metabolic activation of nitrosamines.
The preventive effects of acidic xylooligosaccharide against contact hypersensitivity were investigated in mice. Percutaneous administration of acidic xylooligosaccharide at a dose of 0.10 mg/ear exhibited suppressive activity against contact hypersensitivity in mice. Oral administration at a dose of 200 mg/kg body weight also showed the same effects. Xylan, xylobiose, and glucuronic acid, sugars related to acidic xylooligosaccharide, exhibited suppressive effects on contact hypersensitivity only following oral administration at a dose of 200 mg/kg body weight. These results suggest that daily intake of acidic xylooligosaccharide may be advantageous for the prevention of contact hypersensitivity.
TR-TBT-18d-1 and -18d-2 are syncytiotrophoblast cell lines established from the placenta of a transgenic rat harboring a temperature-sensitive simian virus 40 large T-antigen (Tg-rat). To explore the functional roles of drug metabolizing enzymes in the syncytiotrophoblasts of the placenta, we analyzed the gene expression of both cytochrome P450 (CYP) and phase II conjugation enzymes in these TR-TBT cell lines. A relatively high level of expression of CYP1A1 and CYP2C11 was detectable in the 18d-1 cells whereas CYP2E1 was more strongly expressed in the 18d-2 cells. A moderate degree of expression of CYP2B2 and CYP3A, and low expression of CYP1A2, was observed in both cell lines, but no CYP3A2 was detectable in either. Relatively high levels of SULT2 family gene expression were also evident in these TR-TBT cells, although the SULT1 family genes were found to be either absent or present at only moderate levels. Strong expression of both the UGT1 and UGT2 subfamily, and also the glutathione S-transferase (GST) subfamily, was also observed in both cell lines. These results suggest that TR-TBT cells are a useful model system for the study of syncytiotrophoblasts, which act as a protective fetal barrier against harmful xenobiotics.
Here we show a quantitative, spatial interpretation of influenza propagation process in Tokyo and its environs in the season from November 1st, 2004 to October 31st, 2005. The time lags (day) of influenza propagation between distant sites are calculated by the cross-correlation functions of the daily variations in the amount of drug sale at community pharmacies. The influenza infection appears to have spread from the urban area of Tokyo to its suburbs in the season of 2004-05. From the time lags and distances of the pharmacy locations, the mean propagation speed is estimated to be 3.5 km/day.
In the gross anatomy laboratory, which is one of the compulsory subjects in most medical and dental schools, participants cannot avoid exposure to formaldehyde (FA), which is emitted from cadavers during dissection. FA has been recognized as a harmful chemical and we have previously reported that symptoms felt by participants in a gross anatomy laboratory are similar to those of allergic diseases. Although immunoglobulin E (IgE)-mediated sensitization to FA is a matter of controversy, it is possible that IgE production is evoked during a gross anatomy laboratory and is responsible for the reported symptoms. In order to test this hypothesis, we examined the relationships between the personal FA exposure levels and plasma IgE levels in a gross anatomy laboratory. In the laboratory, the personal FA exposure levels ranged from 0.33 to 1.47 ppm. Total blood IgE levels did not increase significantly and specific IgE to FA was negative during the laboratory sessions. Thus, from this study, we cannot support the hypothesis that the exposure to FA triggers an IgE-mediated reaction in this study. In conclusion, exposure to FA does not induce IgE production during gross anatomy laboratories at our school.