• BMB Reports
• /
• v.48 no.12
• /
• pp.702-707
• /
• 2015

To overcome the disadvantages of stem cell-based cell therapy like low cell survival at the disease site, we used stanniocalcin 2 (STC2), a family of secreted glycoprotein hormones that function to inhibit apoptosis and oxidative damage and to induce proliferation. STC2 gene was transfected into two kinds of stem cells to prolong cell survival and protect the cells from the damage by oxidative stress. The stem cells expressing STC2 exhibited increased cell viability and improved cell survival as well as elevated expression of the pluripotency and self-renewal markers (Oct4 and Nanog) under sub-lethal oxidative conditions. Up-regulation of CDK2 and CDK4 and down-regulation of cell cycle inhibitors p16 and p21 were observed after the delivery of STC2. Furthermore, STC2 transduction activated pAKT and pERK 1/2 signal pathways. Taken together, the STC2 can be used to enhance cell survival and maintain long-term stemness in therapeutic use of stem cells.

• BMB Reports
• /
• v.42 no.10
• /
• pp.655-660
• /
• 2009

The potential anti-metastasis and anti-invasion activities of early growth response gene-1 (Egr-1) and claudin-3, a tight junction (TJ)-related protein, were evaluated using histone deacetylase (HDAC) inhibitors in human hepatocarcinoma cells. The results of wound healing and Transwell assays showed that HDAC inhibitors such as trichostatin A and sodium butyrate inhibited cell migration and invasion. HDAC inhibitors markedly induced Egr-1 expression during the early period, after which expression levels decreased. In addition, the down-regulation of snail and type 1 insulin-like growth factor receptor (IGF-1R) in HDAC inhibitor- treated cells induced the upregulation of thrombospondin-1 (TSP-1), E-cadherin and claudin-3. Cells transfected with Egr-1 and claudin-3 siRNA displayed significant blockage of HDAC inhibitor-induced anti-invasive activity. Collectively, these findings indicate that the up-regulation of Egr-1 and claudin-3 are crucial steps in HDAC inhibitor-induced anti-metastasis and anti-invasion.

• Development and Reproduction
• /
• v.4 no.2
• /
• pp.243-250
• /
• 2000

To find the mechanism underlying the ADP-induced increase in the outward current in ovulated mouse oocytes, we examined changes in voltage-dependent currents using the whole cell voltage clamp technique and the internal perfusion technique. Eggs were collected from the oviduct of superovulated mice with PMSG and hCG. Membrane potential was held at -60 mV (or -80 mV in the case of recording $Ca^{2＋}$ currents) and step depolarizations or hyperpolarizations were applied for 300 ms. By step depolarizations, outward currents comprising steady-state and time-dependent components were elicited. They were generated in response to the positive potential more than 20 mV with severe outward rectification and were blocked by external TEA, a specific $K^{＋}$ channel blocker, suggesting that they be carried via $K^{＋}$ channels. Internally-perused 5 mM ADP gradually increased outward $K^{＋}$ currents (IK) 1 min after perfusion of ADP and reached slowly to maximum (150~170％) 5 min later over the positive potential range, implying that ADP might not be acted directly to the $K^{＋}$ channels. IK were decreased by 5 mM ATP without affecting the steady-state component of outward current. In contrast to the effect of ADP and ATP on IK, both effect of ATP and ADP on inward $Ca^{2＋}$ currents (ICa) could not be detected due to the continuous decrease in current amplitudes with time-lapse ("run-down" phenomena). To check if there is a G protein-involved regulation in the ionic current of mouse oocytes, 1 mM GTP was applied to the cytoplasmic side, and the outward current and inward currents were recorded. ICa was promptly increased in the presence of GTP whereas IK was not changed. from these results, it is concluded that the ATP-dependent regulation is likely linked in the ADP-induced increase in the outward $K^{＋}$ current, and G protein-involved cellular signalling might affect ion channels carrying $Ca^{2＋}$ and $K^{＋}$ in mouse oocytes.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.22 no.4
• /
• pp.821-828
• /
• 2008

Onchungeum, a herbal formula, which has been used for treatment of anemia due to bleeding, discharging blood and skin disease. In the present study, it was examined the effects of extract of Onchungeum (OCE) on the growth of human hepatocarcinoma cell lines Hep3B (p53 null type) and HepG2 (p53 wild type) in order to investigate the anti-proliferative mechanism by OCE. Treatment of Hep3B and HepG2 cells to OCE resulted in the growth inhibition in a dose-dependent manner, however Hep3B cell line exhibited a relatively strong anti-proliferative activity to OEC. Flow cytometric analysis revealed that OCE treatment in Hep3B cells caused G1 phase arrest of the cell cycle, which was associated with various morphological changes in a dose-dependent fashion. RT-PCR and immunoblotting data revealed that treatment of OCE caused the down-regulation of cyclin D1 expression, however the levels of cyclin E expression were not changed by OCE. The G1 arrest of the cell cycle was also associated with the induction of Cdk inhibitor p27 by OCE. Because the p53 gene is null in Hep3B cells, it is most likely that the induction of p21 is mediated through a p53-independent pathway. Moreover, p27 detected in anti-Cdk4 and anti-Cdk2 immunoprecipitates from the OCE-treated cells, suggesting that OCE-induced p27 protein blocks Cdk kinase activities by directing binding to the cyclin/Cdk complexes. Furthermore, OCE treatment potently suppresses the phosphorylation of retinoblastoma proteins and the levels of the transcription factor E2F-1 expression. Taken together, these results indicated that the growth inhibitory effect of OCE in Hep3B hepatoma cells was associated with the induction of G1 arrest of the cell cycle through regulation of several major growth regulatory gene products.

• Korean Journal of Pharmacognosy
• /
• v.47 no.4
• /
• pp.343-351
• /
• 2016

The purpose of this study was to evaluate the whitening effect of aerial part of Pueraria lobata and mechanisms. Aerial part of Pueraria lobata, dose-dependently reduced the melanin content. Aerial part of Pueraria lobata, significantly decreased cellular tyrosinase activity, while there was not any effect on tyrosinase in cell-free conditions. To elucidate the mechanisms behind the aerial part of Pueraria lobata, treated melanogenesis regulation, the expressions of melanogensis related genes, proteins, and the activity of ${\alpha}-glucosidase$ were determined. Aerial part of Pueraria lobata, significantly inhibited gene and protein levels of MITF, tyrosinase and TRP-1. It suppressed the ${\alpha}-glucosidase$, leading to inhibition on the maturation of tyrosinase. Also aerial part of Pueraria lobata, was observed to have the high antioxidant activity. These results suggested that whitening effect of aerial part of Pueraria lobata, should be due to the down-regulation of MITF, tyrosinase and TRP-1 expression and the intercepting maturation of tyrosinase through suppressing ${\alpha}-glucosidase$. Another should be the high anti-oxidant activity. The findings show the possibility that aerial part of Pueraria lobata, can be used as a potential skin-whitening agent.

• Asian-Australasian Journal of Animal Sciences
• /
• v.24 no.9
• /
• pp.1211-1216
• /
• 2011

Sexual maturity in poultry is controlled by a complex neural circuit located in the basal forebrain, which integrates the central and peripheral signals to activate hypothalamic gonadotrophin-releasing hormone (GnRH) secretion. This study demonstrated the changes of GnRH-I, POMC and NPY mRNA transcription in hypothalamus and IGF-I and leptin levels in serum of Shaoxing ducks during puberty. Body weight increased progressively from d30 to d120 and at d120 the flock reached 5% of laying rate. A significant upregulation of hypothalamic GnRH-I mRNA expression was observed from d60, reaching the peak at d120. POMC and NPY mRNA expression in hypothalamus showed a similar pattern, which increased from d30 to d60, followed by a significant decrease towards sexual maturity. Serum IGF-I levels exhibited two peaks at d30 and d120, respectively. Serum leptin displayed a single peak at d90. The results indicate that the down-regulation of POMC and NPY genes in hypothalamus coincides with the up-regulation of GnRH-I gene to initiate sexual maturation in ducks. In addition, peripheral IGF-I and leptin may relay the peripheral metabolic status to the central system and contribute to the initiation of the reproductive function in ducks.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.34 no.5
• /
• pp.518-524
• /
• 2008

Chromosome 18q alteration plays a key role in colorectal tumorigenesis, and loss of heterozygosity at 18q is associated with a poor prognosis in colon cancer. DCC(Deleted in Colorectal Cancer) is a putative tumor- suppressor gene at 18q21 that encodes a transmembrane protein with structural similarity to neural cell adhesion molecule that is involved in both epithelial and neuronal cell differentiation. DCC is implicated in regulation of cell growth, survival and proliferation. Thus, tumor progression in squamous cell carcinoma, stomach cancer, colorectal cancer correlates with downregulation of DCC expression. The mechanism for DCC suppression is associated with hypermethylation of the DCC gene promoter region. Hence, the goal of this study is to identify the promoter methylation responsible for the down-regulation of DCC expression in oral squamous cell carcinoma. 12 of tissue specimens for the study are excised and gathered from 12 patients who are diagnosed as SCC in department of OMS, dental hospital, dankook university. To find expression of DCC in each tissue samples, immunohistochemical staining, RT-PCR gene analysis and methylation specific PCR are processed. The results are as follows. 1. In the DCC gene RT-PCR analysis, 5(41.6%) of 12 specimens of oral squamous cell carcinoma did not expressed DCC gene. 2. In the promoter methylation specific PCR analysis, 5(41.6%) of 12 specimens showed promoter methylation of DCC gene. 3. In the immunohistochemical staining of poor differentiated and invasive oral squamous cell carcinoma, loss of DCC expression was observed. These findings suggest that methylation of the DCC gene may play a role in loss of gene expression in invasive oral squamous cell carcinoma.

• Herbal Formula Science
• /
• v.21 no.2
• /
• pp.53-62
• /
• 2013

Objectives : Diabetic nephropathy is associated with morbidity and mortality of diabetes mellitus patients. Mesangial cell proliferation is known as the major pathologic features such as glomerulosclerosis. Oryeong-san, Korean formula, is widely used for the treatment of nephrosis, edema, and uremia. Oryeong-san is composed of five herbs: Alismatis Rhizoma, Polyporus, Atractylodis Rhizoma Alba, Hoelen, and Cinnamomi Cortex. Methods : The present study was performed to investigate potent inhibitory effect of Oryeong-san on high glucose (HG)-induced rat mesangial cells (RMC) proliferation. Results : RMC proliferation under 25 mM glucose was significantly accelerated compared with 5.5 mM glucose, which was inhibited by Oryeong-san in dose dependent manner. Pre-treatment of Oryeong-san induced down-regulation of cyclins/CDKs and up-regulation of CDK inhibitor, p21waf1/cip1 and p27kip1 expression. In addition, Oryeong-san reduced HG-induced RMC proliferation by suppressed the mitogen-activated protein kinase (MAPK) phospholyration such as extracellular signal regulated kinase (ERK), Jun N-terminal Kinase (JNK), and p38. Oryeong-san significantly suppressed HG-induced ROS production. Conclusions : Oryeong-san consequently inhibited HG-induced mesangial cell proliferation through the inhibition of MAPK and ROS signaling pathway. These results suggest that Oryeong-san may be effective in the treatment of renal dysfunction leading to diabetic nephropathy.

• The Journal of Korean Medicine
• /
• v.29 no.1
• /
• pp.167-178
• /
• 2008

Object : Gliosis becomes a physical and mechanical barrier to axonal regeneration. Reactive gliosis induced by hypoxic brain injury is involved with up-regulation of CD81 and GFAP. The current study was to examine the effect of the Angelica Sinens on CD81 and GFAP regulation after hypoxic brain injury in the astrocyte. Methods : MTT assay was performed to examine cell viability, and cell based ELISA, western blot and PCR were used to detect the expression of CD81 and GFAP. Results : The following results were obtained: 1. Using ELISA, western blot and PCR from the astrocyte after hypoxic injury, CD81 and GFAP expression was seen to have increased. 2. After the administration of Angelica Sinens extract to astrocyte following hypoxic injury, CD81 and GFAP expression was down regulated significantly. The water extract of Angelica Sinens prevented cell destruction by hypoxic induced with $CoCl_2$. Conclusion : These results indicate that Angelica Sinens could suppress reactive gliosis, which disturbs astrocyte regeneration after hypoxic brain injury by controlling the expression of CD81 and GFAP.

• Biomedical Science Letters
• /
• v.23 no.4
• /
• pp.327-332
• /
• 2017

A2B adenosine receptor (A2BAR) is known to be a regulator of bone homeostasis, but the regulatory mechanism of A2BAR on the osteoclast proliferation are poorly explored. Recently, we have shown that stimulation with BAY 60-6583, a specific agonist of A2BAR, significantly reduced macrophage-colony stimulating factor (M-CSF)-induced osteoclast proliferation by inducing cell cycle arrest at G1 phase and increasing the apoptosis of osteoclasts. The objective of this study was to investigate the regulatory mechanisms of cell cycle and apoptosis by A2BAR stimulation. The expression of A2BAR and M-CSF receptor, c-Fms, was not changed by A2BAR stimulation whereas M-CSF effectively induced c-Fms expression during osteoclast proliferation. Interestingly, A2BAR stimulation remarkably increased the expression of $p27^{Kip-1}$, a cell cycle inhibitor, but the expression of Cyclin D1 and cdk4 was not affected. In addition, while BAY 60-6583 treatment reduced the expression of Bcl2, an anti-apoptotic oncogene, it failed to regulate the expression of Bax, a pro-apoptotic marker. Taken together, these results imply that the increase of $p27^{Kip-1}$ inducing cell cycle arrest at G1 phase and the decrease of Bcl2 inducing anti-apoptotic response by A2BAR stimulation contribute to the down-regulation of osteoclast proliferation.