• Journal of Preventive Medicine and Public Health
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• v.38 no.3
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• pp.330-336
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• 2005

Objectives : The aim of this study was to investigate the effects of bisphenol A (BPA), an estrogen-like environmental endocrine disrupter, on the placental function and reproduction in rats. The mRNA levels of the placental prolactin-growth hormone(PRL-GH) gene family, placental trophoblast cell frequency and reproductive data were analyzed. Methods : The pregnancies of F344 Fisher rats ($160g{\pm}20g$) were detected by the presence of the copulatory plug or sperm in the vaginal smear, which marked Day 0 of pregnancy. Pregnant rats were divided into three groups. The control group was intraperitoneally injected with a sesame oil vehicle. The two remaining groups were injected with 50 or 500 mg/kg B.W/day of BPA, resuspended in sesame oil, on either days 7 to 11 or 16 to 20 of pregnancy, with the rats sacrificed on either day 11 or 20, respectively. The mRNA levels of PRL-GH and Pit-1a and b isotype genes were analyzed by Northern blot hybridization and reverse transcription-polymerase chain reaction. The hormone concentrations were analyzed by radioimmunoassay, and the frequency of the placental trophoblast cells observed by a histochemical study. Reproductive data, such as the placental weight and litter size, were surveyed on day 20. The fetal weight was surveyed for 4 weeks after birth. A statistical analysis was carried out using the SAS program (version 8.1). Results : The mRNA levels of the PRL-GH gene family, such as placental lactogen I, Iv and II, prolactin like protein A, C and Cv, and decidual prolactin-related protein were significantly reduced due to BPA exposure. The mRNA levels of the Pit-1a and b isotype genes, which induce the expression of the PRL-GH gene family in the rat placenta, were also reduced due to BPA exposure. The PL-Iv and PL-II concentrations were reduced in the BPA exposed group. During the middle to last stage of pregnancy (Days 11-20), a high dose of BPA exposure reduced the frequency of spongiotrophoblast cells, which are responsible for the secretion of the PRL-GH hormones. Reproductive data, such as the placental and fetal weights and the litter size, were reduced, but that of the pregnancy period was extended in the BPA exposed compared to the control group. Conclusions : BPA disrupts the placental functions in rats, which leads to reproductive disorders.

• Journal of Preventive Medicine and Public Health
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• v.36 no.2
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• pp.93-100
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• 2003

Objectives : Because shipyard workers are involved with various manufacturing process, they are exposed to many kinds of hazardous materials. Welders especially, are exposed to bisphenol-A (BPA) during the welding and flame cutting of coated steel, This study was conducted to assess the exposure status of the endocrine disrupter based on the job-exposure matrix. The effects of the genetic polymorphism of xenobiotic enzyme metabolisms involved in the metabolism of BPA on the levels of urinary metabolite were investigated. Methods : The study population was recruited from a shipyard company in the f province. A total of 84 shipbuilding workers 47 and 37 in the exposed and control groups, respectively, were recruited for this study. The questionnaire variables included, age, sex, use of personal protective equipment, smoking, drinking and work duration. The urinary metabolite was collected in the afternoon and correction made for the urinary creatinine concentration. The of the CYP1A1, CYP2E1 and UGT1A6 genotypes were investigated using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods with the DNA extracted from venous blood. Results : The urinary BPA level in the welders group was significantly higher than in the control group (p<0.05). The urinary BPA concentration with the wild type UGT1A6 was higher than the other UGT1A6 genotypes, but with no statistical significant. From themultiple regression analysis of the urinary BPA, the regression coefficient for job grade was statistically significant (p<0.05). Conclusions : The grade of exposure to BPA affected the urinary BPA concentration was statistically significant. However, the genetic polymorphisms of xenobiotics enzyme metabolism were not statistically significant. Further investigation of the genetic polymorphisms with a larger sample size is needed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.4
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• pp.471-479
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• 2012

This study was conducted to investigate the effects of various levels of chitosan oligomer (CO) molecular weight on the disorders of lipid metabolism and immune-related factors induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), that is a endocrine disrupter, using adult male rats (SD) for 3 weeks. These 40 animals were divided into five groups. Three kinds of CO were used by molecular weight (MW) (less than 1000, 1000~3000, and 5000~10000) and added 4% to basal diets respectively. TCDD (40 ${\mu}g$/kg B.W) was intraperitoneally injected into rats at the beginning of the experiment. The relative weights of the livers were increased in all rats treated with TCDD, and the brain and testis weights were increased in all CO diet groups, compared to the control and TCDD groups. The levels of white blood cells (WBC) and red blood cells (RBC), hemoglobin, hematocrits (HCT), and platelets were significantly lowered by treating TCDD. By the way, RBC and HCT tended to recover by CO diets. The elevation of serum total and HDL cholesterol levels induced by TCDD treatment was significantly reduced by CO (5000~10000 MW) diets. The apparent increasing of the total lipid, cholesterol, and triglyceride levels of rat livers induced by TCDD was tended to be suppressed in those fed CO diets. Especially, diets with less than 1000 MW significantly diminished liver triglycerides. The levels of serum immunoglobulin (Ig) A, IgG1 and IgM were significantly high in rats fed CO (5000~10000 MW) diets. The decreasing levels of IgE by treatment with TCDD tended to recover all the CO diet groups to the level of control group. In histochemical observation, the fat droplets and apoptosis of liver due to TCDD treatment were markedly alleviated in all CO diet groups. These results indicated that CO, though not regular according to molecular weight, can exert improving effects on lipid accumulation, hepatocytic disorders, abnormal blood cells, and some immunoglobulins induced by TCDD.