• Korean Journal of Environmental Biology
• /
• v.37 no.1
• /
• pp.72-81
• /
• 2019

Bisphenol A (BPA), a representative endocrine disrupting chemicals, has adverse effects on growth, development and reproduction in aquatic organisms. The object of this study was to investigate the modulation of antioxidant enzyme-coding genes using quantitative real time RT-PCR (qRT-PCR), enzyme activity and total protein content, to understand oxidative stress responses after exposure to BPA for 48 h in brackish water flea Diaphanosoma celebensis. The BPA ($3mg\;L^{-1}$) significantly upregulated the expression of Cu/Zn-SOD, Mn-SOD, and catalase (CAT) mRNA. Three GST isoforms (GST-kappa, GST-mu, and GST-theta) mRNA levels significantly increased at the rate of $0.12mg\;L^{-1}$ of BPA. In particular, GST-mu showed the highest expression level, indicating its key role in antioxidant response to BPA. SOD activity was induced with a concentration-dependent manner, and total protein contents was reduced. These findings indicate that BPA can induce oxidative stress in this species, and these antioxidants may be involved in cellular protection against BPA exposure. This study will provide a better understanding of molecular mode of action of BPA toxicity in aquatic organisms.

• Journal of Ginseng Research
• /
• v.44 no.3
• /
• pp.519-526
• /
• 2020

Background: Bisphenol A (BPA), known as an endocrine disruptor, is widely used in the world. BPA is reported to cause inflammation-related diseases. Korean Red Ginseng (KRG) has been used safely in human for a long time for the treatment of diverse diseases. KRG has been reported of its mitigating effect on menopausal symptoms and suppress adipose inflammation. Here, we investigate the protective effect of orally administered KRG on the impacts of BPA in the liver and uterus of menopausal mice model. Methods: The transcriptome analysis for the effects of BPA on mice liver was evaluated by Gene Expression Omnibus (GEO) database-based data (GSE26728). In vivo assay to evaluate the protective effect of KRG on BPA impact in ovariectomized (OVX) mice were designed and analyzed by RNA sequencing. Results: We first demonstrated that BPA induced 12 kinds of gene set in the liver of normal mice. The administration of BPA and KRG did not change body, liver, and uterine weight in OVX mice. KRG downregulated BPA-induced inflammatory response and chemotaxis-related gene expression. Several gene set enrichment analysis (GSEA)-derived inflammatory response genes increased by BPA were inhibited by KRG in OVX mice. Conclusion: Our data suggest that BPA has commonly influenced inflammatory response effects on both normal and OVX mice. KRG protects against BPA impact of inflammatory response and chemotaxis in OVX mouse models. Our comparative analysis will provide new insight into the efficacy of KRG on endocrine disrupting chemicals and OVX mouse.

• Clinical and Experimental Reproductive Medicine
• /
• v.38 no.2
• /
• pp.75-81
• /
• 2011

Objective: Bisphenol A (BPA) is a chemical used extensively to manufacture plastics and epoxy resin liners for food and beverage cans. BPA, with properties similar to estrogen, has endocrine-disrupting effects. In the present study, we examined the effects of early prepubertal BPA exposure on the onset of puberty and reproductive parameters such as estrous cycle and reproductive organ weights in female mice. Methods: Female mice were injected subcutaneously at postnatal day (PND) 8 with BPA (0.1, 1, 10, 100 mg/kg) in sesame oil or with sesame oil alone. Body weight was measured from PND 10 to 70. Vaginal opening and estrous cycle were monitored from PND 20 to 29. Animals were sacrificed at PND 25, 30, and 70, and the ovary and uterus weights were measured. Results: Early prepubertal exposure to BPA (10 and 100 mg/kg) significantly decreased body weight from PND 18 to 30. BPA treated mice at testing dose levels showed early opening of the vagina compared to the control group. The number of estrous cycle and days of estrus were significantly decreased in high dose (100 mg/kg) BPA treated mice. The ovary weight at PND 25 and 30 was significantly decreased in all BPA treatment groups. Conclusion: Early prepubertal exposure to BPA accelerated the onset of puberty but decreased reproductive parameters in female mice.

• Molecules and Cells
• /
• v.23 no.3
• /
• pp.287-303
• /
• 2007

Expressed sequence tags (ESTs) and differentially expressed cDNAs from the self-fertilizing fish, Kryptolebias marmoratus were mined to develop alternative biomarkers for endocrine-disrupting chemicals (EDCs). 1,577 K. marmoratus cDNA clones were randomly sequenced from the 5'-end. These clones corresponded to 1,518 and 1,519 genes in medaka dbEST and zebrafish dbEST, respectively. Of the matched genes, 197 and 115 genes obtained Unigene IDs in medaka dbEST and zebrafish dbEST, respectively. Many of the annotated genes are potential biomarkers for environmental stresses. In a differential display reverse transcriptase-polymerase chain reaction (DD RT-PCR) study, 56 differential expressed genes were obtained from fish liver exposed to bisphenol A. Of these, 16 genes were identified after BLAST search to GenBank, and the annotated genes were mainly involved in catalytic activity and binding. The expression patterns of these 16 genes were validated by real-time RT-PCR of liver tissue from fish exposed to bisphenol A. Our findings suggest that expression of these 16 genes is modulated by endocrine disrupting chemicals, and therefore that they are potential biomarkers for environmental stress including EDCs exposure.

• Journal of Life Science
• /
• v.17 no.2 s.82
• /
• pp.266-271
• /
• 2007

Bisphenol A (BPA) has been widely used as a monomer for production of epoxy resins and polycarbonate plastics. The annual production of BPA exceeds 640,000 metric tons in worldwide. BPA, a suspected phenolic endocrine disrupter, is moderately soluble and frequently detected in industrial wastewater. To date, HPLC and GC has been used for BPA analysis. However, HPLC and GC-analysis need high operation lost, experts, and an elaborate pre-treatment of samples, and is difficult to apply on-time and mass analysis. Therefore, simple, mass and rapid detection of BPA in environments is necessary. In the present study, spectrophotometric method of BPA quantification was developed. Based on blue-color product formation with BPA and ferric chloride/ferricyanide under the optimized conditions, the standard curve was acquired $({\lambda}_{750}=0.061\;BPA\;[{\mu}M]+0.07155,\;R^2=0.992)$. Using an established method, the BPA contents in the soil extract, and different water samples and living products, including disposable syringe, cup and plastic tube, were analyzed. The results suggested that the method is useful for BPA determination from different massive samples. Since the BPA metabolites, nontoxic 4-hydroxyacetophenone or 4-hydroxybenzaldehyde, did not form blue-color product, this method is also useful to screen a microorganism for BPA bioremediation.

• Toxicological Research
• /
• v.20 no.3
• /
• pp.251-261
• /
• 2004

A large number of chemical pollutants including phthalates, alkylphenolic compounds and organochlorine pesticides have the ability to disrupt endocrine function in animals, and alter cog-nitive function. Because hormone mediated events play an important role in central nervous system development and function, the changes in cognitive function seem to be mediated by the endocrine-like action of these chemicals. The present study therefore was designed to investigate effect of bisphenol A (BPA), an endocrine disrupting chemical on neuro-behavial patterns, and expression of estrogen receptors and tyrosine hydroxylase, a limiting enzyme of dopamine synthesis pathway. BPA was treated orally for 3 weeks into 3 week old mice, and then the neuro-behavial patterns (stereo-type behaviors such as jumping rearing and forepaw tremor, climbing behavior, tail flick, rotarod and locomotor activity), and the expression of estrogen receptors and tyrosine hydroxylase were deter-mined every 3 week for 9 weeks. During the treatment of BPA, the food uptake and body weight increase were not significantly changed. BPA resulted in the increased stereotype behaviors (jump-ing, rearing and forepaw tremor) 6 or 9 weeks after treatment. The time response to tail flick and locomotor activity were decreased by the treatment of BPA, whereas the time for rotarod was increased by the treatment of BPA. The expression of estrogen receptor alpha and beta was increased in the brain and pituitary gland. Maximum expression was found in the brain after 9 week of 100 mg/kg BPA treatment and in the pituitary gland after 6 week of 100 mg/kg BPA treatment. Tyrosine hydroxylase was increased in dose and time dependent manners in the brain but no change was found in the pituitary gland. The present data show that exposure of BPA in the young mice could alter expression of estrogen receptors and dopamine synthesis pathway, thereby modulate neuro-behavial patterns (increase of stereotype behaviors but decrease locomotor activity).

• Korean Journal of Environmental Biology
• /
• v.19 no.1
• /
• pp.59-69
• /
• 2001

Among the biodegradability tests, TOC-HANDAI and OECD method were utilized to examine the degree of biodegradation of endocrine disruptors, Bisphenol A (BPA) and Nonylphenol. Both methods used natural water microcosms and measured their biodegrada-bilities of BPA and Nonylphenol, in terms of TOC or DOC degradation with time for 28 days. Biodegradabilities for BPA, 73-78% with TOC-HANDAI method and 77-81% with OECD method were obtained respectively at the end of experiment. There was no difference in BPA degradation between two methods. BPA degradation was described by two distinct first order decay rates (k$_1$ and k$_2$) which could be separated by a simple visual fitting. Most of the initial decay reaction accelerated within 1-7 days with k$_1$of 0.24-0.34 $day^{-1}$. And the following another long term first order decay coefficient (k$_2$) showed 0.02-0.05 day$^{-1}$ with much flat slope. About 20-25% of initial BPA remained at the end of experiment. It suggests that the remaining TOC components in BPA biodegradation considered to be refractory metabolites of BPA. Nonylphenol at each sampling point was appeared to be mineralized 20-48% of initial TOC concentration. Consequently Nonylphenol seems more recalcitrant against biodegradation. BPA was not detected in the detection limit of ppb in the watershed of Daechung reservoir and Kum river. However 25 ppb concentration of BPA was detected at the influent of industrial wastewater treatment plant in Taejon.

• Korean Journal of Materials Research
• /
• v.3 no.1
• /
• pp.95-100
• /
• 1993

Abstract Fourier transform infrared (FT -IR) instrument was used to st.udy the thermoset behavior of DGEBA/MDA system with succinonit.rile. That was experimented with the samples which were cured from 8$0^{\circ}C$ to 17$0^{\circ}C$ every 3$0^{\circ}C$ for 1 hour and uncured with different SN content. respect.ively. It was known that prImary amine hydrogen reacted wit.h epoxide group, secondary amine hydrogen with epoxide group and hydroxyl with epoxide group. In addition. the reaction of primary amine hydrogen with nitrile gorup of SN and of hydroxyl group with nitrile group of SN came about. These t.wo reactions made chain bond length longer between main chains.

• Journal of Conservation Science
• /
• v.28 no.2
• /
• pp.131-139
• /
• 2012

The exothermic cure kinetics of epoxy resin was controlled by hardener containing fast and slow curing agents. The epoxy risen comprises hydrogenated bisphenol A-based epoxide (HBA), fast curing agent (FH) and slow curing agent poly(propyleneglycol)bis(2-aminopropylether) (SH). Talc was used as an inorganic additive. In the process of curing, cure kinetics along with temperature was monitored by differential scanning calorimeter (DSC) and thermocouple to show that the temperature increase was well controlled by adjusting the hardener mixture. Additionally, bending and tensile strengths of the epoxy/talc composites were also measured to be lower and higher with the amount of the talc inorganic additive, respectively. It is thus concluded that the increase in the temperature during exothermic curing reaction and mechanical properties of epoxy resins are tuned by optimizing hardener mixture for successful stone conservation.

• Biomolecules & Therapeutics
• /
• v.17 no.2
• /
• pp.188-198
• /
• 2009

This work was conducted to investigate the effect of bisphenol A (BPA) on estradiol (E2) 2-and 4-hydroxylase activities in the liver, kidney and lung tissues of male and female rats. After intraperitoneal administration of BPA to male and female rats for 4 days at 0, 10, and 50 mg/kg, the conversion of the substrate for hepatic and extra-hepatic enzyme activities was measured by GC/MSD. The result showed decreases of body and organ weights at 50 mg/kg BPA of male and female rats. Male hepatic E2 2-hydroxylase activity was inhibited by 68% at 10 mg/kg and by 82% at 50 mg/kg BPA. Female hepatic E2 2-hydroxylase activity was decreased by 46% at 10 mg/kg and by 56% at 50 mg/kg to the control. E2 4-hydroxylase was inhibited by 57 and 57% at 10 mg/kg and 54 and 78% at 50 mg/kg in liver of female and male, respectively. The urinary excretion rate of 2-hydroxyestradiol (2-OHE), androsterone and testosterone in urine of female rats with 50 mg/kg BPA were decreased significantly. The results showed that 50 mg/kg BPA was decreased E2 2-and 4-hydroxylase activities in liver, but not in other tissues. The urinary excretion rates of 2-OHE, androsterone and testosterone were also decreased. In liver, estrogenic enzyme activity were higher in male than female. These results suggest that BPA can disrupt estrogen metabolism by suppressing E2 2-and 4-hydroxylase activities in the liver of male and female rats.