• Journal of Microbiology and Biotechnology
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• v.28 no.2
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• pp.236-245
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• 2018

Ingredients of soy and fermented soy products have been widely utilized as food supplements for health-enhancing properties. The aim of this study was to evaluate the effects of fermented soymilk (FSM) and soymilk (SM) on free fatty acid-induced lipogenesis in the hepatocellular steatosis model. HepG2 cells were incubated with palmitic acid (PA) for 24 h to induce lipogenesis and accumulation of intracellular lipid contents. The PA-treated cells were co-incubated with FSM, SM, genistein, and estrogen, respectively. Lipid accumulation in the PA-treated HpG2 cells was significantly decreased by co-incubation with FSM. Treatment of HepG2 cells with PA combined with genistein or estrogen significantly increased the expression of SREBP-1. However, FSM co-incubation significantly attenuated SREBP-1 expression in the PA-treated HepG2 cells; in addition, expression of NRF-2 and phosphorylation of ERK were significantly increased in the PA and FSM co-incubated cells. PA-induced ROS production was significantly reduced by FSM and SM. Our results suggested that the bioactive components of FSM could protect hepatocytes against the lipid accumulation and ROS production induced by free fatty acids. These effects may be mediated by the inhibition of SREBP-1 and the activation of NRF-2 via the ERK pathway in HepG2 cells.

• Molecules and Cells
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• v.40 no.9
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• pp.677-684
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• 2017

Postmenopausal atrophic vagina (PAV) is the thinning of the walls of the vagina and decreased lugae of the vagina. PAV is caused by decreased estrogen levels in postmenopausal women. However, the harmful effects of hormone replacement therapy (HRT) have resulted in considerable caution in its use. Various estrogen agonist treatment options are available. Vitamin D is influences the regulation of differentiation and proliferation of various cells, especially tissues lining stratified squamous epithelium, such as the vaginal epithelium. In this study, we hypothesized that vitamin D could provide an alternative and a safe treatment option for PAV by promoting the proliferation and differentiation of the vaginal epithelium. Thirty six patients were enrolled in this case-control study. Vitamin D associated proteins in a vitamin D and sex hormone treated vaginal epithelial cell line as well as normal and PAV tissues were measured. To confirm of cell-to-cell junction protein expression, cell line and tissue studies included RT-PCR, immunohistochemistry staining, and immunoblot analyses. The expression of cell-to-cell junction proteins was higher in women with symptoms of atrophic vagina tissue compared to women without the symptoms. Vitamin D stimulated the proliferation of the vaginal epithelium by activating p-RhoA and Erzin through the vitamin D receptor (VDR). The results suggest that vitamin D positively regulates cell-to-cell junction by increasing the VDR/p-RhoA/p-Ezrin pathway. This is the first study to verify the relationship of the expression of RhoA and Ezrin proteins in vaginal tissue of PAV.

• Molecules and Cells
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• v.38 no.2
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• pp.138-144
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• 2015

Raloxifene is a selective estrogen receptor modulator (SERM) that binds to the estrogen receptor (ER), and exhibits potent anti-tumor and autophagy-inducing effects in breast cancer cells. However, the mechanism of raloxifene-induced cell death and autophagy is not well-established. So, we analyzed mechanism underlying death and autophagy induced by raloxifene in MCF-7 breast cancer cells. Treatment with raloxifene significantly induced death in MCF-7 cells. Raloxifene accumulated GFP-LC3 puncta and increased the level of autophagic marker proteins, such as LC3-II, BECN1, and ATG12-ATG5 conjugates, indicating activated autophagy. Raloxifene also increased autophagic flux indicators, the cleavage of GFP from GFP-LC3 and only red fluorescence-positive puncta in mRFP-GFP-LC3-expressing cells. An autophagy inhibitor, 3-methyladenine (3-MA), suppressed the level of LC3-II and blocked the formation of GFP-LC3 puncta. Moreover, siRNA targeting BECN1 markedly reversed cell death and the level of LC3-II increased by raloxifene. Besides, raloxifene-induced cell death was not related to cleavage of caspases-7, -9, and PARP. These results indicate that raloxifene activates autophagy-dependent cell death but not apoptosis. Interestingly, raloxifene decreased the level of intracellular adenosine triphosphate (ATP) and activated the AMPK/ULK1 pathway. However it was not suppressed the AKT/mTOR pathway. Addition of ATP decreased the phosphorylation of AMPK as well as the accumulation of LC3-II, finally attenuating raloxifene-induced cell death. Our current study demonstrates that raloxifene induces autophagy via the activation of AMPK by sensing decreases in ATP, and that the overactivation of autophagy promotes cell death and thereby mediates the anti-cancer effects of raloxifene in breast cancer cells.

• Korean Journal of Food Science and Technology
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• v.51 no.4
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• pp.361-368
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• 2019

The present study aimed to evaluate the effect of Dendropanax morbifera (DM) extract on postmenopausal syndrome and to develop DM extract as an alternative for hormonal therapy. The following seven groups of rats; normal control (sham), ovariectomized (OVX) control, Punica granatum (PG)-treated group (770 mg/kg), estradiol treated group (0.5 mg/kg), and three DM-treated groups (200, 500, 1000 mg/kg) were compared. Indicated compounds were administrated once a day for eight weeks. To evaluate the estrogenic effect of DM extract, western blot analysis was performed on the liver tissue to confirm the expression of estrogen receptor ($ER-{\alpha}$, $ER-{\beta}$). Our analysis showed that after DM administration, collagen cross-linked C-telopeptide (CTX) value decreased while $ER-{\alpha}$ protein expression increased in a dose-dependent manner through the MAPK/ERK pathway in OVX rats. These results suggest that Dendropanax morbifera exerts estrogenic effect by inducing estrogen receptor expression and activating MAPK/ERK pathway.

• Journal of Life Science
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• v.26 no.12
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• pp.1383-1391
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• 2016

Anti-estrogen drugs such as tamoxifen have been used for treating patients with ER-positive, early breast cancer. However, resistance to anti-estrogen treatment is inevitable in most patients. Breast cancer anti-estrogen resistance-3 (BCAR3) has been identified as the protein responsible for the induction of tamoxifen resistance in estrogen-dependent human breast cancer. We have previously reported that BCAR3 regulates the cell cycle progression and the signaling pathway of EGF and insulin leading to DNA synthesis. In this study, we investigated the functional role of BCAR3 in regulating c-Jun transcription in non-tumorigenic human breast epithelial MCF-12A cells. A transient transfection of BCAR3 increased both the mRNA and protein of c-Jun expression, and stable expression of BCAR3 increased c-Jun protein expression. The overexpression of BCAR3 directly activated the promoter of c-jun, AP-1, and SRE but not that of $NF-{\kappa}B$. Furthermore, single-cell microinjection of BCAR3 expression plasmid in the cell cycle-arrested MCF-12A cells induced c-Jun protein expression, and co-injection of dominant negative mutants of Ras, Rac, and Rho suppressed the transcriptional activity of c-Jun in the presence of BCAR3. Furthermore, stable expression of BCAR3 increased the proliferation of MCF-12A cells. The microinjection of inhibitory materials such as anti-BCAR3 antibody and siRNA BCAR3 inhibited EGF-induced c-Jun expression but did not affect IGF-1 induced upregulation of c-Jun. Taken together, we propose that BCAR3 plays a crucial role in c-Jun protein expression and cell proliferation and that small GTPases (e.g., Ras, Rac, and Rho) are required for the BCAR3-mediated activation of c-Jun expression.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.495-499
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• 2014

Estrogens are considered the major breast cancer risk factor, and the carcinogenic potential of estrogens might be attributed to DNA modification caused by derivatives formed during metabolism. $17{\beta}$-estradiol ($E_2$), the main steroidal estrogen present in women, is metabolized via two major pathways: formation of 2-hydroxyestradiol (2-OH $E_2$) and 4-hydroxyestradiol ($4-OH\;E_2$) through the action of cytochrome P450 (CYP) 1A1 and 1B1, respectively. Previous reports suggested that $2-OH\;E_2$ has putative protective effects, while $4-OH\;E_2$ is genotoxic and has potent carcinogenic activity. Thus, the ratio of $2-OH\;E_2/4-OH\;E_2$ is a critical determinant of the toxicity of $E_2$ in mammary cells. In the present study, we investigated the effects of berberine on the expression profile of the estrogen metabolizing enzymes CYP1A1 and CYP1B1 in breast cancer MCF-7 cells. Berberine treatment produced significant induction of both forms at the level of mRNA expression, but with increased doses produced 16~ to 52~fold greater induction of CYP1A1 mRNA over CYP1B1 mRNA. Furthermore, berberine dramatically increased CYP1A1 protein levels but did not influence CYP1B1 protein levels in MCF-7 cells. In conclusion, we present the first report to show that berberine may provide protection against breast cancer by altering the ratio of CYP1A1/CYP1B1, could redirect $E_2$ metabolism in a more protective pathway in breast cancer MCF-7 cells.

• Journal of Ginseng Research
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• v.37 no.3
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• pp.315-323
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• 2013

Ginseng is known to have antistress effects. Previously, red ginseng (RG) was shown to repress stress-induced peptidyl arginine deiminase type IV (PADI4) via estrogen receptor ${\beta}$ ($ER{\beta}$) in the brain, thus inhibiting brain cell apoptosis. Moreover, tumor necrosis factor (TNF)-${\alpha}$ plays a critical role in immobilization (IMO) stress. However, the signaling pathway of RG-mediated repressesion of inflammation is not completely understood. In this study, we determined how RG modulated gene expression in stressed brain cells. Since secretion of TNF-${\alpha}$ is modulated via TNF-${\alpha}$ converting enzyme (TACE) and nuclear factor (NF)-${\kappa}B$, we examined the inflammatory pathway in stressed brain cells. Immunohistochemistry revealed that TACE was induced by IMO stress, but RG repressed TACE induction. Moreover, PADI4 siRNA repressed TACE expression compared to the mock transfected control suggesting that PADI4 was required for TACE expression. A reporter assay also revealed that $H_2O_2$ oxidative stress induced NF-${\kappa}B$ in neuroblastoma SK-N-SH cells, however, RG pretreatment repressed NF-${\kappa}B$ induction. These findings were supported by significant induction of nitric oxide and reactive oxygen species (ROS) by oxidative stress, which could be repressed by RG administration. Taken together, RG appeared to repress stress-induced PADI4 via TACE and NF-${\kappa}B$ in brain cells thus preventing production of ROS and subsequently protecting brain cells from apoptosis.

• Journal of Ginseng Research
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• v.42 no.2
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• pp.123-132
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• 2018

Ginseng has gained its popularity as an adaptogen since ancient days because of its triterpenoid saponins, known as ginsenosides. These triterpenoid saponins are unique and classified as protopanaxatriol and protopanaxadiol saponins based on their glycosylation patterns. They play many protective roles in humans and are under intense research as various groups continue to study their efficacy at the molecular level in various disorders. Ginsenosides Rb1 and Rg1 are the most abundant ginsenosides present in ginseng roots, and they confer the pharmacological properties of the plant, whereas ginsenoside Rg3 is abundantly present in Korean Red Ginseng preparation, which is highly known for its anticancer effects. These ginsenosides have a unique mode of action in modulating various signaling cascades and networks in different tissues. Their effect depends on the bioavailability and the physiological status of the cell. Mostly they amplify the response by stimulating phosphotidylinositol-4,5-bisphosphate 3-kinase/protein kinase B pathway, caspase-3/caspase-9-mediated apoptotic pathway, adenosine monophosphate-activated protein kinase, and nuclear factor kappa-light-chain-enhancer of activated B cells signaling. Furthermore, they trigger receptors such as estrogen receptor, glucocorticoid receptor, and N-methyl-$\text\tiny{D}$-aspartate receptor. This review critically evaluates the signaling pathways attenuated by ginsenosides Rb1, Rg1, and Rg3 in various tissues with emphasis on cancer, diabetes, cardiovascular diseases, and neurodegenerative disorders.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.6803-6812
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• 2015

Caveolin-1 is a 22-kD trans-membrane protein enriched in particular plasma membrane invaginations known as caveolae. Cav-1 expression is often dysregulated in human breast cancers, being commonly upregulated in cancer cells and downregulated in stromal cells. As an intracellular scaffolding protein, Cav-1, is involved in several vital biological regulations including endocytosis, transcytosis, vesicular transport, and signaling pathways. Several pathways are modulated by Cav-1 including estrogen receptor, EGFR, Her2/neu, $TGF{\beta}$, and mTOR and represent as major drivers in mammary carcinogenesis. Expression and role of Cav-1 in breast carcinogenesis is highly variable depending on the stage of tumor development as well as context of the cell. However, recent data have shown that downregulation of Cav-1 expression in stromal breast tumors is associated with frequent relapse, resistance to therapy, and poor outcome. Modification of Cav-1 expression for translational cancer therapy is particularly challenging since numerous signaling pathways might be affected. This review focuses on present understanding of Cav-1 in breast carcinogenesis and its potential role as a new biomarker for predicting therapeutic response and prognosis as well as new target for therapeutic manipulation.

• Korean Journal of Veterinary Service
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• v.31 no.4
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• pp.457-463
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• 2008

The sex steroid hormone estradiol-$17{\beta}(E_2)$ mediate their biological effects on development, differentiation and maintenance of reproductive tract and other target tissue through gene regulation by nuclear steroid receptors. Although the importance of $E_2$ in many physiological process has been reported, but little is known about the effects of $E_2$ on primary cultured chicken hepatocyte. therefore, in the present study, we have examined the effect of $E_2$ on cell proliferation and it's related signal cascades. $E_2$ increase $[^3H]$-thymidine incorporation in time-(${\leq}8hr$) and dose-($10^{-10}M$)dependent manner and treatment of $E_2$ increased the phosphorylation of p44/43 MAPKs(p44/42 mitogen-activated protein kinase) and JNK(c-Jun N-terminal kinase) in a time dependent manner. In addition, PD98059(p44/42 blocker, $10^{-5}M$), SP600125(JNK blocker, $10^{-6}M$) blocked the estrogen-induced increase in $[^3H]$-thymidine incorporation. In conclusion, $E_2$ stimulates the proliferation of primary cultured chicken hepatocytes and this action is mediated by p44/42 MAPKs and JNK signal transduction pathway.