• Journal of Life Science
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• v.22 no.11
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• pp.1500-1506
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• 2012

Transforming growth factor (TGF)-${\beta}$-dependent apoptosis is important in the elimination of damaged or abnormal cells from normal tissues, especially in liver, in vivo. To investigate which gene expressions are critical for TGF-${\beta}$-induced apoptosis in hepatocytes, gene expression profiling experiments were performed with TGF-${\beta}$-treated and non-treated mouse hepatocytes AML12 cells. Findings showed that serum and glucocorticoid-inducible protein kinase1 (SGK1) expression is markedly downregulated during TGF-${\beta}$-induced apoptosis. Findings confirmed that expression of SGK1 protein, as well as mRNA, is also markedly decreased with TGF-${\beta}$ treatment. Infection of adenoviral vector encoding constitutively active SGK1 (CA-SGK1), but not kinase dead SGK1 (KD-SGK1), attenuated TGF-${\beta}$-induced apoptosis. All of these results suggest that downregulation of SGK1 expression is critical for TGF-${\beta}$-induced apoptosis in AML12 cells.

• BMB Reports
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• v.41 no.1
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• pp.41-47
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• 2008

Fe65 is characterized as an adaptor precursor (APP) through its PID2 element, as well as with the other members of the APP protein family. With the serum- and glucocorticoid-induced kinase 1 (SGK1) substrate specificity information, we found that the putative site of phosphorylation in Fe65 by SGK1 is present on its $Ser^{566}$ residue in $^{560}CRVRFLSFLA^{569}$(X60469). Thus, we demonstrated that Fe65 and the fluorescein-labeled Fe65 peptide $FITC-^{560}CRVRFLSFLA^{569}$ are phosphorylated in vitro by SGK1. Phosphorylation of the $Ser^{566}$ residue was also demonstrated using a $Ser^{566}$ phospho-specific antibody. The phospho Fe65 was found mainly in the nucleus, while Fe65 S556A mutant was localized primarily to the cytoplasm. Therefore, these data suggest that SGK1 phosphorylates the $Ser^{566}$ residue of Fe65 and that this phosphorylation promotes the migration of Fe65 to the nucleus of the cell.

• Animal cells and systems
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• v.14 no.2
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• pp.99-114
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• 2010

With the consensus sequence information of the serum glucocorticoid-induced protein kinase-1 (SGK1) phosphorylation site {R-X-R-X-X-(S/T)$\Phi$; where $\Phi$ is any hydrophobic amino acid}, we noticed that the transient receptor potential vanilloid 4 (TRPV4) cation channel, a member of the TRP vanilloid subfamily, harbors the putative SGK1 phosphorylation site (on its Ser 824). We have demonstrated that TRPV4 is an SGK1 authentic substrate protein, with the phosphorylation on the Ser 824 of TRPV4 by SGK1. Further, using TRPV4 mutants (S824A and S824D), we noted that the modification of the Ser 824 activates its $Ca^{2+}$ entry, and sensitizes the TRPV4 channel to 4-$\alpha$-phorbol 12,13-didecanoate (4-${\alpha}PDD$) or heat, simultaneously enhancing its active state. Additionally, we determined that the modification of the Ser 824 controls both its plasma membrane localization and its protein interactions with calmodulin. Thus, we have proposed herein that phosphorylation on the Ser 824 of TRPV4 is one of the control points for the regulation of its functions.

• Animal cells and systems
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• v.9 no.3
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• pp.161-171
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• 2005

Integrin-linked kinase 1 (ILK1) regulates several protein kinases, including PKB/Akt kinase and glycogen synthase kinase ${\beta}$. ILK1 is also involved distinctively in the cell morphological and structural functions by interacting with the components of the extracellular matrix or integrin. According to the information of serum- and glucocorticoid-induced kinase 1 (SGK1) substrate specificity (R-X-R-X-X(S/T)-${\phi};{\phi}$ indicates a hydrophobic amino acid), two putative phosphorylation sites, $Thr^{181}\;and\;Ser^{246}$, were found in ILK1. We showed that ILK1 fusion protein and two fluorescein-labeled ILK1 peptides, $FITC-^{174}RTRPRNGTLN^{183}$ and $FITC-^{239}CPRLRIFSHP^{248}$, were phosphorylated by SGK1 in vitro. We also identified that 14-3-3 ${\theta}\;{\varepsilon}\;and\;{\xi}$, among several 143-3 isotypes $({\beta},\;{\gamma},\;{\varepsilon},\;{\eta},\;{\sigma},\;{\theta},\;{\tau}\;and\;{\xi})$ formed protein complex with ILK1 in COS-1 cells. Furthermore, the phosphorylation of $Ser^{246}$ by SGK1 induced the binding with 14-3-3. It was also demonstrated that 14-3-3-bound ILK1 has reduced kinase activity. Thus, these data suggest that SGK1 phosphorylates $Thr^{181}\;and\;Ser^{246}$ of ILK1 and the phosphorylation of its $Ser^{246}$ makes ILK1 bind to 14-3-3, resulting in the inhibition of ILK1 kinase activity.

• Biomedical Science Letters
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• v.21 no.3
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• pp.131-134
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• 2015

High sodium diet has been touted to be a major risk factor of disease in developed countries. The disease most closely associated with a high sodium diet is cardiovascular diseases. Autoimmune diseases are another broad spectrum of diseases that is associated with developed countries. In the past few years, several key scientific findings have revealed that a high sodium diet could also impact the pathogenicity of autoimmune diseases. In this review, we will highlight key results from such investigations and put it in context of high sodium diet and autoimmunity.

• The Korea Journal of Herbology
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• v.36 no.3
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• pp.39-46
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• 2021

Objectives : Mangifera indica leaves are well known for having a variety of benefits, including anti-inflammatory, anti-tumor, diabetic retinopathy and diabetic vasculosis. However, the effects of Mangifera indica leaves on hair loss inhibition have not been studied. In this study, we investigated to find out the activity of Mangifera indica leaves on hair loss. Methods : 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid(ABTS) analysis was performed to confirm the antioxidant efficacy of the water extract of Mangifera indica leaves (WEML). To examine the effect of WEML on cell viability in dermal papillar (DP) cells, 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetra Zolium (MTS) analysis was performed. The changes in the mRNA expression level of the hair loss and hair growth-related genes in dermal papilla cells by WEML treatment were confirmed by quantitative RT-PCR. Results : In dermal papilla (DP) cells, ABTS analysis and MTS analysis of WEML showed antioxidant efficacy and low cytotoxicity. As a result of gene expression analysis through Quantitative RT-PCR, no changes in hair growth-related genes BMP6 and CTNNB1 was confirmed. but inhibitory activity of WEML on hair loss-related genes EGR1, SGK, DKK1, SRD5A1 and SRD5A2 was confirmed. Conclusion : We confirmed that WEML has excellent antioxidant efficacy and a inhibitory activity of hair loss-related genes including 5α-reductase genes. These results suggest that Mangifera indica leaves have a potential activity as a hair loss treatment for hair loss and hair growth. Biochemical or molecular biological research on hair loss is needed.