• Tuberculosis and Respiratory Diseases
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• v.58 no.3
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• pp.267-276
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• 2005

Background : The transforming growth $factor-{\beta}1$ ($TGF-{\beta}1$) plays a key role in lung fibrosis. However, the molecular mechanisms involved in $TGF-{\beta}1$-induced lung fibrosis are unclear. $TGF-{\beta}1$ is the key inducer of myofibroblast transdifferentiation via de novo synthesis of ${\alpha}-smooth$ muscle actin (${\alpha}-SMA$). Since $TGF-{\beta}1$ signals through reactive oxygen species (ROS) and ROS have been shown to induce accumulation of extracellular matrix (ECM) in various tissues, this study examined if ROS play a role in $TGF-{\beta}1$-induced fibronectin secretion and ${\alpha}-SMA$ expression in human lung fibroblasts, MRC-5 cells. Methods : Growth arrested and synchronized MRC-5 cells were stimulated with $TGF-{\beta}1$ (0.2-10 ng/ml) in the presence or absence of N-acetylcysteine (NAC) or diphenyleneiodonium (DPI) for up to 96 hours. Dichlorofluorescein (DCF)-sensitive cellular ROS were measured by FACScan and secreted fibronectin and cellular ${\alpha}-SMA$ by Western blot analysis. Results : $TGF-{\beta}1$ increased the level of fibronectin secretion and ${\alpha}-SMA$ expression in MRC-5 cells in a dosedependent manner. Both NAC (20 and 30 mM) and DPI (1 and $5{\mu}M$) significantly inhibited $TGF-{\beta}1$-induced fibronectin and ${\alpha}-SMA$ upregulation. The $TGF-{\beta}1$-induced cellular ROS level was also significantly reduced by NAC and DPI. Conclusions : The results suggest that NADPH oxidase-dependent ROS play an important role in $TGF-{\beta}1$-induced fibronectin secretion and ${\alpha}-SMA$ expression in MRC-5 cells, which leads to myofibroblast transdifferentiation and progressive lung fibrosis.

• Korean Journal of Clinical Laboratory Science
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• v.39 no.3
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• pp.210-216
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• 2007

There is increasing evidence that stromal reaction in cancer has an important diagnostic and prognostic significance. The aim of our study is to analyze the relation between the increase in mast cell number and the expression CD34 and alpha-smooth muscle actin (${\alpha}$-SMA) in the stroma of cervical intraepithelial neoplasia (CIN) and squamous cell carcinoma (SCC). We investigated a total of 29 CIN (1,2,3) and 21 SCC (microinvasive and invasive) specimens and compared the distribution of $CD34^+$ stromal cells, ${\alpha}-SMA^+$ cells, transforming growth factor-${\beta}1$ $(TGF-{\beta}1)^+$ cells, and the density of mast cells using immunohistochemistry with antibodies against CD34, ${\alpha}$-SMA, TGF-${\beta}1$, and c-Kit (CD117) respectively. Computerized image analysis was to evaluate the positive area (%) and density of the respective immunoreactive cells. In CIN $CD34^+$ cells were abundant in the stroma but no ${\alpha}-SMA^+$ cells were identified except the wall of blood vessels. $CD34^+$ cells were progressively decreased along the continuum from CIN 2 to microinvasive SCC and not observed in the stroma of invasive SCC. Whereas ${\alpha}-SMA^+$ cells were only observed in the stroma of microinvasive and invasive SCC. We found more intense TGF-${\beta}1$ expression in the increased mast cells in the stroma of invasive SCCs than that in the stroma of CIN. These results indicate that disappearance of $CD34^+$ stromal cells and appearance of ${\alpha}-SMA^+$ cells are associated with the stromal change of CIN to SCC and the transformation of $CD34^+$ stromal cells into ${\alpha}-SMA^+$ cells is mediated by TGF-${\beta}1$ secretions in the stromal mast cell of SCC.

• Magazine of the Korea Concrete Institute
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• v.7 no.2
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• pp.175-182
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• 1995

Styrene-Maleic anhydride copolymer (SMA) was prepared by the radical copolmerization of styrene and maleic anhydride using ${\alpha}-{\alpha}'$ azobis(isobutyronitrile) as an initiatrr. SMA was further reacted with m-amino phenol to obtain aminophenol-substituted SMR (mSMA). Sulfonated SMA and mSMA were also prepared by the reaction of copolymers with sulfuric acid The copolyniers were characterized by infrared spectroscopy. It was found from the results of elemental analysis that the substitution degree of aminophenol in the mSMR is 44% and the degree is lowered to 35% after sulfonation. The percentage of copolymers adsorbed on the surface of cement particles was increased with a decrease of added copolymers. While, the arnourit of sulfonated SMA absorbed on the surface of cement particles was larger than that of the sulfonated mSMA The copolymers synthesized in this study are probably expected as a high range water reducer for coiicxte.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.5
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• pp.401-411
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• 2015

Aldose reductase (AR) is known to play a crucial role in the mediation of diabetic and cardiovascular complications. Recently, several studies have demonstrated that allergen-induced airway remodeling and ovalbumin-induced asthma is mediated by AR. Epalrestat is an aldose reductase inhibitor that is currently available for the treatment of diabetic neuropathy. Whether AR is involved in pathogenesis of pulmonary fibrosis and whether epalrestat attenuates pulmonary fibrosis remains unknown. Pulmonary fibrosis was induced by intratracheal instillation of bleomycin (5 mg/kg) in rats. Primary pulmonary fibroblasts were cultured to investigate the proliferation by BrdU incorporation method and flow cytometry. The expression of AR, TGF-${\beta}_1$, ${\alpha}$-SMA and collagen I was analyzed by immunohistochemisty, real-time PCR or western blot. In vivo, epalrestat treatment significantly ameliorated the bleomycin-mediated histological fibrosis alterations and blocked collagen deposition concomitantly with reversing bleomycin-induced expression up-regulation of TGF-${\beta}_1$, AR, ${\alpha}$-SMA and collagen I (both mRNA and protein). In vitro, epalrestat remarkably attenuated proliferation of pulmonary fibroblasts and expression of ${\alpha}$-SMA and collagen I induced by TGF-${\beta}_1$, and this inhibitory effect of epalrestat was accompanied by inhibiting AR expression. Knockdown of AR gene expression reversed TGF-${\beta}_1$-induced proliferation of fibroblasts, up-regulation of ${\alpha}$-SMA and collagen I expression. These findings suggest that AR plays an important role in bleomycin-induced pulmonary fibrosis, and epalrestat inhibited the progression of bleomycin-induced pulmonary fibrosis is mediated via inhibiting of AR expression.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.1
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• pp.37-44
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• 2017

Regulation of vascular smooth muscle cell (VSMC) phenotype plays an essential role in many cardiovascular diseases. In the present study, we provide evidence that $kr{\ddot{u}}ppel$-like factor 8 (KLF8) is essential for tumor necrosis factor ${\alpha}$ ($TNF{\alpha}$)-induced phenotypic conversion of VSMC obtained from thoracic aorta from 4-week-old SD rats. Stimulation of the contractile phenotype of VSMCs with $TNF{\alpha}$ significantly reduced the VSMC marker gene expression and KLF8. The gene expression of KLF8 was blocked by $TNF{\alpha}$ stimulation in an ERK-dependent manner. The promoter region of KLF8 contained putative Sp1, KLF4, and $NF{\kappa}B$ binding sites. Myocardin significantly enhanced the promoter activity of KLF4 and KLF8. The ectopic expression of KLF4 strongly enhanced the promoter activity of KLF8. Moreover, silencing of Akt1 significantly attenuated the promoter activity of KLF8; conversely, the overexpression of Akt1 significantly enhanced the promoter activity of KLF8. The promoter activity of SMA, $SM22{\alpha}$, and KLF8 was significantly elevated in the contractile phenotype of VSMCs. The ectopic expression of KLF8 markedly enhanced the expression of SMA and $SM22{\alpha}$ concomitant with morphological changes. The overexpression of KLF8 stimulated the promoter activity of SMA. Stimulation of VSMCs with $TNF{\alpha}$ enhanced the expression of KLF5, and the promoter activity of KLF5 was markedly suppressed by KLF8 ectopic expression. Finally, the overexpression of KLF5 suppressed the promoter activity of SMA and $SM22{\alpha}$, thereby reduced the contractility in response to the stimulation of angiotensin II. These results suggest that cross-regulation of KLF family of transcription factors plays an essential role in the VSMC phenotype.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.6
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• pp.807-814
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• 2016

Fucoidan, one of the dominant sulfated polysaccharides extracted from brown seaweed, possesses a wide range of biological activities. Transforming growth $factor-{\beta}$ ($TGF-{\beta}$) plays a pivotal role in the pathogenesis of pulmonary fibrosis, by stimulating the synthesis of profibrotic factors. In this study, we investigated the in vitro effects of fucoidan on collagen synthesis, ${\alpha}-smooth$ muscle actin (${\alpha}-SMA$) expression, and interleukin (IL)-6 production in $TGF-{\beta}$-stimulated human pulmonary fibroblasts. The expression of type I collagen and ${\alpha}-SMA$ was detected by Western blot, and the production of IL-6 by enzyme-linked immunosorbent assay. $TGF-{\beta}1$ treatment of pulmonary fibroblasts enhanced the expression of ${\alpha}-SMA$, type I collagen, and IL-6 whereas these effects were inhibited in cells pretreated with fucoidan. The activation of Smad2/3, p38 mitogen-activated protein kinases (MAPKs), and Akt was also inhibited in fucoidan-pretreated, $TGF-{\beta}1-stimulated$ human pulmonary fibroblasts. These data demonstrate the anti-fibrotic potential of fucoidan in $TGF-{\beta}-induced$ human pulmonary fibroblasts, via the inhibition of Smad2/3, p38 MAPKs, and Akt phosphorylation. Our results suggest the therapeutic potential of fucoidan in the prevention or treatment of pulmonary fibrosis.

• Clinical and Experimental Pediatrics
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• v.52 no.8
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• pp.944-952
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• 2009

Purpose : To investigate the effects of angiotensin II inhibition on the epithelial to mesenchymal transition (EMT) in the developing kidney, we tested the expression of EMT markers and nestin in angiotensin converting enzyme (ACE) inhibitor-treated kidneys. Methods : Newborn rat pups were treated with enalapril (30 mg/kg/d) or a vehicle for 7 days. Immunohistochemistry for the expression of ${\alpha}$-smooth muscle actin (SMA), E-cadherin, vimentin, and nestin were performed. The number of positively-stained cells was determined under 100 magnification in 10 random fields. Results : In the enalapril-treated group, ${\alpha}SMA-positive$ cells were strongly expressed in the dilated tubular epithelial cells. The number of ${\alpha}SMA-positive$ cells in the enalapril-treated group increased in both the renal cortex and medulla, compared to the control group (P<0.05). The expression of E-cadherin-positive cells was dramatically reduced in the cortical and medullary tubular epithelial cells in the enalapril-treated group (P<0.05). The number of vimentin- and nestin-positive cells in the cortex was not different in comparisons between the two groups; however, their expression increased in the medullary tubulointerstitial cells in the enalapril-treated group (P<0.05). Conclusion : Our results show that ACE inhibition in the developing kidney increases the renal EMT by up-regulating ${\alpha}SMA$ and down-regulating E-cadherin. Enalapril treatment was associated with increased expression of vimentin and nestin in the renal medulla, suggesting that renal medullary changes during the EMT might be more prominent, and ACE inhibition might differentially modulate the expression of EMT markers in the developing rat kidney.

• Journal of Korean Biological Nursing Science
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• v.8 no.2
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• pp.41-59
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• 2006

Chronic liver diseases and hepatic cancer have been reported as 10% of cause of death in Koreans. Regardless of various causes, chronic liver disease accompanies commonly hepatic fibrosis. But still the mechanism of hepatic fibrosis remains poorly understood. Using the dimethylnitrosamine(DMN)-induced hepatic fibrosis rat model, We performed to evaluate the possible therapeutic effect of RIP(extracts of Phellodendron amurense and Patrinia scabiosaefolia) and to investigate the changes in referential connective tissue proteins($TGF-{\beta}_1$, ${\alpha}$-smooth muscle actin, and vimentin) as a marker of fibrogenesis. For these purposes, liver tissues were stained with H & E, and Azan staining for estimation of developing fibrosis. In the DMN-treated rat liver tissue, fibrosis were developed forming incomplete septal fibrosis. Whereas, in the RIP-treated rat liver tissues, the fibrosis were decreased recovering to normal morphology. The expressions of $TGF-{\beta}_1$, ${\alpha}$-smooth muscle actin($\alpha-SMA$), and vimetin were increased in the DMN-treated rat liver tissues, but decreased in the various areas of RIP-treated rat liver tissues. According to these results, RIP could be a possible therapeutic agent to reduce hepatic fibrosis, and the $TGF-{\beta}_1$, ${\alpha}$-SMA, and vimentin could be possible indicative markers of hepatic fibrosis development and recovery.

• Childhood Kidney Diseases
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• v.15 no.2
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• pp.125-137
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• 2011

Purpose : Men are generally more prone to chronic renal disease and progression to end stage renal disease than women. The purpose of this study is to prove the effect of gender and sex hormone on renal fibrosis in mice with unilateral ureteral obstruction (UUO) and to elucidate the specific underlying mechanisms. Methods :We compared the expression of ${\alpha}$-smooth muscle actin (${\alpha}$-SMA) in female and male mice with complete UUO (day 7). After this, we estimated the changes of renal fibrosis in the female mice with oophorectomy and in the female mice with oophorectomy and replacement of $17{\beta}$-estradiol, respectively. Results : The level of ${\alpha}$-SMA in the female kidney with UUO was significantly lower than that in the male kidney with UUO. oophorectomy and replacement of $17{\beta}$-estradiol did not change the expression of angiotensin II type 1 (AT1) receptor in the female kidney with UUO, whereas the expression of angiotensin II type 2 (AT2) receptor was significantly more elevated in the intact female (IF) and the oophorectomized female with estrogen (OF+E) than that in the oophorectomized female (OF). The expressions of inducible nitric oxide synthase (iNOS) in the IF and OF+E mice were significantly more elevated than that in the OF mice, which was similar to the expression of AT2 receptor. Conclusion : The female gender is associated with resistance to renal fibrosis in obstructive uropathy and this gender difference may originate from the existence of $17{\beta}$-estradiol, which has an anti-fibrotic effect via upregulation of the AT2 receptor and iNOS.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.4
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• pp.161-169
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• 2008

Purpose: To better understand the corneal regeneration after alkali burn regarding the initial clinical progression and the therapy, we investigated the changes of the multi factors following chemical injury in cornea. Methods: This study was performed to observation on the healing process of alkali burned cornea in aspect of immunohistochemistry by immunofluorescence or H-E staining and TUNEL assay. Results: The results showed that although a healing process occurred after alkali burn, apoptosis of epithelial, stromal and endothelial cells in the cornea was continuously observed. Neovascularization and expression of ${\alpha}$-smooth muscle actin (${\alpha}$-SMA) from limbus and from injured cornea, respectively, were observed after 3 days of alkali burn. Formation of collagen III in corneal stroma and increased expression of chondroitin sulfate are coincident with expression of ${\alpha}$-SMA and transforming growth factor-${\beta}$ (TGF-${\beta}$). Conclusions: These data suggest that medical treatment within 3 days of alkali burn will be effective to inhibit neovascularization and formation of collagen III and chondroitin sulfate. This study extends our immumohistochemical understanding of healing process in alkali burned cornea, and the results get in this study will be cornerstones in the development of therapeutic agent for accelerating renewal of chemical damaged cornea.