Differentiated embryo chondrocyte-2 (DEC2), also known as bHLHE41 or Sharp1, is a pleiotropic transcription repressor that controls the expression of genes involved in cellular differentiation, hypoxia responses, apoptosis, and circadian rhythm regulation. Although a previous study demonstrated that DEC2 participates in the circadian control of hepatic metabolism by regulating the expression of cytochrome P450, the molecular mechanism is not fully understood. We reported previously that brief exposure of HepG2 cells to 50% serum resulted in 24-h oscillation in the expression of CYP3A4 as well as circadian clock genes. In this study, we found that the expression of CYP2D6, a major drug-metabolizing enzyme in humans, also exhibited a significant oscillation in serum-shocked HepG2 cells. DEC2 interacted with CCAAT/enhancer-binding protein (C/EBP␣), accompanied by formation of a complex with histone deacetylase-1, which suppressed the transcriptional activity of C/EBP␣ to induce the expression of CYP2D6. The oscillation in the protein levels of DEC2 in serum-shocked HepG2 cells was nearly antiphase to that in the mRNA levels of CYP2D6. Transfection of cells with small interfering RNA against DEC2 decreased the amplitude of CYP2D6 mRNA oscillation in serumshocked cells. These results suggest that DEC2 periodically represses the promoter activity of CYP2D6, resulting in its circadian expression in serum-shocked cells. DEC2 seems to constitute a molecular link through which output components from the circadian clock are associated with the time-dependent expression of hepatic drug-metabolizing enzyme.

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Nephrotoxicity was more marked in rats receiving isepamicin at midlight than at middark. And, the once-daily administration at middark induced a lesser degree of nephrotoxicity than the twice-daily injection, which indicates that the once-daily treatment therapy may have potential value in the clinical use of aminoglycosides.

The aim of the present study was to investigate whether diabetes model can be made by treatment of streptozotocin (STZ) in chick embryos and this model can be used to predict the effect of drug. When STZ (0.3 mg/egg) was injected into the albumen of fertile eggs on the 14th day of incubation, level of blood glucose significantly increased than that of the control on the 17th day of incubation, and level of serum insulin significantly decreased. In addition, the enhanced level of blood glucose in STZ-treated embryos reduced by injection of human insulin. In conclusion, STZ-treated embryos may be applicable to evaluate human insulin and anti-diabetes drugs as an experimental diabetes model.

Doping is one of the most serious problems for athletes, and it is important that pharmacists have more interaction with athletes to ensure safer drug usage. Education is one of the most important roles of sports pharmacists, who are specialists regarding drug usage for athletes. We investigated pharmacy students' interests and comprehension regarding drug usage, doping and supplement intake by using the form of a questionnaire, since it is important to know how they understand these subjects as part of their greater educational program. The subjects were sophomore and junior pharmacy students at three universities. It was revealed that most of the students have negative images regarding doping violation, and they answered that they are familiar with doping. However, only sixteen percent of the students had attended lectures by specialists on doping. In addition, one third of pharmacy students did not know that some over-the-counter (OTC) drugs might contain doping substances. With regard to supplement intake, approximately two thirds of the respondents had an interest in and positive image of supplement intake. However, it was revealed that only one third of them recognized supplements as food, and their information regarding supplements was obtained from uncertain media. It was suggested that it is important for pharmacy students to have more opportunities to learn about what doping is. More education and enlightenment by sports pharmacists would be effective for pharmacy students as well as athletes, and it would help us to broaden the scope of what we can do for athletes and society.