• 대한약리학회:학술대회논문집
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• 2006.11a
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• pp.35-35
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• 2006

• BMB Reports
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• v.48 no.3
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• pp.131-138
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• 2015

Cardiac hypertrophy is a form of global remodeling, although the initial step seems to be an adaptation to increased hemodynamic demands. The characteristics of cardiac hypertrophy include the functional reactivation of the arrested fetal gene program, where histone deacetylases (HDACs) are closely linked in the development of the process. To date, mammalian HDACs are divided into four classes: I, II, III, and IV. By structural similarities, class II HDACs are then subdivided into IIa and IIb. Among class I and II HDACs, HDAC2, 4, 5, and 9 have been reported to be involved in hypertrophic responses; HDAC4, 5, and 9 are negative regulators, whereas HDAC2 is a pro-hypertrophic mediator. The molecular function and regulation of class IIa HDACs depend largely on the phosphorylation-mediated cytosolic redistribution, whereas those of HDAC2 take place primarily in the nucleus. In response to stresses, posttranslational modification (PTM) processes, dynamic modifications after the translation of proteins, are involved in the regulation of the activities of those hypertrophy-related HDACs. In this article, we briefly review 1) the activation of HDAC2 in the development of cardiac hypertrophy and 2) the PTM of HDAC2 and its implications in the regulation of HDAC2 activity.

• Molecules and Cells
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• v.41 no.2
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• pp.140-149
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• 2018

The $TIS21^{/BTG2/PC3}$ gene belongs to the antiproliferative gene (APRO) family and exhibits tumor suppressive activity. However, here we report that TIS21 controls lipid metabolism, rather than cell proliferation, under fasting condition. Using microarray analysis, whole gene expression changes were investigated in liver of TIS21 knockout (TIS21-KO) mice after 20 h fasting and compared with wild type (WT). Peroxisome proliferator-activated receptor alpha ($PPAR{\alpha}$) target gene expression was almost absent in contrast to increased lipid synthesis in the TIS21-KO mice compared to WT mice. Immunohistochemistry with hematoxylin and eosin staining revealed that lipid deposition was focal in the TIS21-KO liver as opposed to the diffuse and homogeneous pattern in the WT liver after 24 h starvation. In addition, cathepsin E expression was over 10 times higher in the TIS21-KO liver than that in the WT, as opposed to the significant reduction of thioltransferase in both adult and fetal livers. At present, we cannot account for the role of cathepsin E. However, downregulation of glutaredoxin 2 thioltransferase expression might affect hypoxic damage in the TIS21-KO liver. We suggest that the $TIS21^{/BTG2}$ gene might be essential to maintain energy metabolism and reducing power in the liver under fasting condition.

• 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.37 no.2
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• pp.157-165
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• 2004

Objectives : This study aimed to investigate the toxic effects of chromium (VI) on the placental function and reproduction in rats. For the study, the placental prolactin-growth hormone (PRL-GH) gene expression, placental trophoblast cell differentiation and reproductive data were analyzed. Methods : The pregnancies of F344 Fisher rats were checked by the presence of a copulatory plug or sperm in the vaginal smear, which was defined as day 0 of the pregnancy. Pregnant rats were divided into the three groups. The control group was given tap water (chromium level < 0.001 ppm) and the remaining groups were given 250 or 750 ppm of chromium (VI) [as potassium dichromate], from day 7 to 19 of the pregnancy. Rats were sacrificed at days 11 and 20 of pregnancy. 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 (RT-PCR). The hormonal concentration was analyzed by radioimmunoassay, and the differentiation of placental trophoblast cells were observed by histochemical studies. Reproductive data, such as placental and fetal weights, pregnancy period, and litter size, were surveyed at day 20 of pregnancy and after birth. A statistical analysis was carried out using the SAS program (version 8.1). Results : The mRNA levels of the prolactin-growth hormone (PRL-GH) family of genes were dose dependently reduced by chromium exposure. The mRNA levels of Pit-1a and b isotype genes that induce the expression of the PRL-GH family of genes were also reduced by chromium exposure. The PRL-GH hormonal concentration in the rat placenta, fetus and maternal blood were decreased by chromium exposure. In the middle stage of pregnancy (day 11), a high dose of chromium suppressed the differentiation of spongiotrophoblast cells that secret the PRLGH hormones. In the last stage of pregnancy (day 20), a high dose of chromium induced apoptosis of placental cells. Reproductive data, such as placental and fetal weights, litter size, were reduced, but the pregnancy period was extended in the group exposed to chromium compared with the controls. Conclusion : Chromium (VI) disrupts the ordered functions of the placenta, which leads to reproductive disorders in rats.