Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is an ubiquitous antioxidant enzyme, but the exact expression pattern in mammalian tissues is still unknown. The expression and cellular localization of PHGPx mRNA were examined in male mice using real time-polymerase chain reaction and in situ hybridization techniques. The rank order of PHGPx mRNA expression across tissues exhibiting substantial levels of expression was:testes >> heart > cerebrum > or = ileum > stomach = liver = jejunum > or = epididymis. In testes, PHGPx mRNA was highly expressed in spermiogenic cells and Leydig cells. The signal was also expressed in the molecular layer, Purkinje cell layer, and white matter of cerebellum, the pituicytes of neurohypophysis, the parafollicular cells and follicular basement membrane of thyroid, the exocrine portion of pancreas, the tubular epithelium of kidney, the smooth muscle cells of arteries, and the red pulp of spleen. In the gastrointestinal tract, PHGPx mRNA expression was mainly observed in the keratinized surface epithelium of forestomach, the submucosal glands and serosa layers, and further the Paneth cells of intestines. PHGPx mRNA appeared to be ubiquitously expressed in the parenchyma of heart, liver, and lung. These results indicate that PHGPx exhibits a cell- and tissue-specific expression pattern in mice.

(1-BP) in SD rats were investigated. LC50 for four-hour exposure was 14,374 ppm (95% confidence limit: 13,624-15,596 ppm). It was revealed to be irritating to the eyes with lacrimation in all fourhour exposure rats. No other abnormal clinical signs and gross findings related to the 1-BP exposure were observed. An experiment on repeated exposure to 0, 50, 300, and 1,800 ppm for six hrs/day, five days/week, for eight weeks was conducted.A decrease in body weights and increase in relative liver weight in both male and female rats were observed in the 1,800 ppm exposure group (p<0.001 vs. control group). No other significant changes in feed consumption, urinanalysis, hematology and serum biochemistry were observed. Histopathological examinations did not reveal any 1-BP-related changes. (J Occup Health 1999; 41: 121-128)

Abstract. Expression of 3β-hydroxysteroid dehydrogenase (3β-HSD) is mainly found in the Leydig cells from which steroid hormones are biosynthesized in the testes. To investigate whether endocrine disruptors affect the microenvironment of the testes, the mRNA expression of 3β-HSD as a molecular marker for androgen biosynthesis was analyzed in rat testes exposed to several endocrine disruptors using a reverse transcription-polymerase chain reaction technique. Testosterone [50, 200 and 1,000 µg/kg body weight (BW)], flutamide (1, 5 and 25 mg/kg BW), ketoconazole (0.2, 1, 5 and 25 mg/kg BW), diethylhexyl phthalate (10, 50 and 250 mg/kg BW), nonylphenol (10, 50, 100 and 250 mg/kg BW), octylphenol (10, 50 and 250 mg/kg BW), and diethylstilbestrol (10, 20 and 40 µg/kg BW) were orally administered to 4-week-old Sprague-Dawley rats for 3 weeks daily. Although testosterone at a low dose (50 µg/kg/day) increased the expression of 3β-HSD mRNA, it was significantly decreased in the rats treated with 200 or 1,000µg/kg/day testosterone compared with the control group (P<0.05). Furthermore, ketoconazole, diethylhexyl phthalate, nonylphenol, octylphenol and diethylstilbestrol caused significant downregulation of 3β-HSD mRNA in the testes at all doses (P<0.05). However, flutamide remarkably increased the level of 3β-HSD mRNA in the testes (P<0.05). These results suggest that endocrine disruptors may influence androgen biosynthesis in the testes by alteration of 3β-HSD mRNA expression.

This study was to investigate the anti-obesity effects of diglyceride (DG)-conjugated linoleic acid (CLA) containing 22% CLA as fatty acids in C57BL/6J ob/ob male mice. There were four experimental groups including vehicle control, DG, CLA, and DG-CLA. The test solutions of 750 mg/kg dose were orally administered to the mice everyday for 5 weeks. CLA treatments significantly decreased mean body weight in the obese mice throughout the experimental period compared to the control (p < 0.01). All test solutions significantly decreased the levels of triglyceride, glucose and free fatty acids in the serum compared with control (p < 0.05). The levels of total cholesterol were also significantly reduced in DG and DG-CLA groups compared with the control group (p < 0.05). CLA significantly decreased weights of renal and epididymal fats compared with the control (p < 0.05). DG and DG-CLA also significantly decreased the epididymal fat weights compared with the control (p < 0.05). A remarkable decrease in the number of lipid droplets and fat globules was observed in the livers of mice treated with DG, CLA, and DG-CLA compared to control. Treatments of DG and CLA actually increased the expression of peroxisome proliferator-activated receptor gamma. These results suggest that DG-CLA containing 22% CLA have a respectable anti-obesity effect by controlling serum lipids and fat metabolism.

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