• Journal of Life Science
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• v.34 no.4
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• pp.227-235
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• 2024

Hepatocyte damage caused by medications or herbal products is one of the important problem when these compounds are chronically administrated. Thus, improving hepatocyte survival during treatment offers a wide range of opportunities. Valproic acid (VPA), a branched short-chain fatty acid derived from naturally occurring valeric acid, is commonly used to treat epilepsy and seizures. Although VPA exerts numerous effects in cancer, HIV therapy, and neurodegenerative disease, its effects on the liver and its mechanism of action have not been fully elucidated. Here, we demonstrated that VPA caused moderate liver cell toxicity and apoptosis. Interestingly, VPA treatment increased transcription levels of PPAR alpha (PPAR-α) and fibroblast growth factor 21 (FGF21) in murine (Hepa1c1c7) hepatoma cells in a time and concentration dependent manner. VPA-induced FGF21 expression was significantly weaker under PPAR-α silencing condition than in cells transfected with non-targeting control siRNA. Subsequent experiments showed that cell viability was significantly lowered when the FGF21 signaling pathway was blocked by FGF receptor antagonist. Finally, we further determined that AMPK phosphorylation was not responsible for VPA-induced FGF21 expression and PPAR-a increments. These results indicate that increases of FGF21 expression alleviate VPA-induced hepatic toxicity, thereby making FGF21 a potential biomarker for predicting liver damage during VPA treatments.

• East Asian mathematical journal
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• v.21 no.1
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• pp.61-64
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• 2005

Let R be a commutative ring with identity, and let $f,\;g_i(i=1,\;\ldots,\;n),\;g_{\alpha}(\alpha{\in}S)$ be elements of R. We show that the following statements are equivalent; (i) $X_f{\subseteq}{\cup}_{\alpha{\in}S}X_{g\alpha}$ only if $X_f{\subseteq}X_{g\alpha}$ for some $\alpha{\in}S$, (ii) $V(f){\subseteq}{\cup}_{\alpha{\in}S}V(g_{\alpha})$ only if $V(f){\subseteq}V(g_{\alpha})$ for some $\alpha{\in}S$, (iii) $V(f){\subseteq}{\cup}^n_{i=1}V(g_i)$ only if $V(f){\subseteq}V(g_i)$ for some i, (iv) Spec(R) is linearly ordered under inclusion.

• Bulletin of the Korean Chemical Society
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• v.21 no.5
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• pp.483-486
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• 2000

A method is described for the fluorimetric determination of nickel, based on the formation of $Ni(II)-\alpha-(2-Benzimidazolyl)-\alpha'$, $\alpha''$ -(N-5-Nitro-2-Pyridylhydrazone)-toluene complex in the presence of a non-ionic surfactant. The complex has practically no fluorescence in the absence of surfactant, but the addition of Triton X-100 makes possible the fluorimetric determination of low concentrations of Ni(II) as it enhances the fluorescenceintensity of the complex by up to about 5-fold. This method is very sensitive and selectrive for the direct determination of nickel ion. The optimum conditions are a Triton X-100 concentration of 2.0 mL(5.0%, v/v) and pH $9.0\pm0.2(ammonium$ chloride-ammonia buffer). The fluorescence is measured at 337 nm of emission wavelength under 300 nm of excitation wavelength. The fluorescence intensity is a linear function of the concentration of Ni(II) in the range 5-70 ng/mL, and the detection limit is 2.0 nm/mL. The proposed method has been successfully applied to the determination of trace amounts of Ni(II) in food and human hair samples.

• Korean Journal of Mathematics
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• v.21 no.4
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• pp.455-462
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• 2013

Let D be an integral domain, S be a saturated multi-plicative subset of D such that $D_S$ is a factorial domain, $\{X_{\alpha}\}$ be a nonempty set of indeterminates, and $D[\{X_{\alpha}\}]$ be the polynomial ring over D. We show that S is a splitting (resp., almost splitting, t-splitting) set in D if and only if every nonzero prime t-ideal of D disjoint from S is principal (resp., contains a primary element, is t-invertible). We use this result to show that $D{\backslash}\{0\}$ is a splitting (resp., almost splitting, t-splitting) set in $D[\{X_{\alpha}\}]$ if and only if D is a GCD-domain (resp., UMT-domain with $Cl(D[\{X_{\alpha}\}]$ torsion UMT-domain).

• Archives of Pharmacal Research
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• v.9 no.2
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• pp.93-97
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• 1986

Fourteen volatile components including eight allypyrocatechol analogs were isolated and identified from the essential oil and ether soluble fraction of Philippine Piper bettle leaves (Piperaceae). The major constituents of Philippine Piper betle oil were chavibetol and chavibetol acetate. Capilary GC analysis of the oil showed chavibetol (53.1%), chavibetol acetate (15.5%), caryophyllene (3.79%), allypyrocatechol diacetate (0.71%), campene (0.48), chavibetol methylether (=methyl eugenol, 0.48%), eugenol (0/32%), $\alpha$-pinene(0.21%), $\beta$-pinene(0.21%), $\alpha$-limonene(0.14%), safrole (0.11%), 1.8-cineol(0.04%), and allylpyrocatechol monoacetate. The major component of the ether soluble fraction was allylpyrocatechol (2.38% of the leaves).

• Microbiology and Biotechnology Letters
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• v.40 no.4
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• pp.348-355
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• 2012

In the present study, we investigated the overexpression and characterization of bovine pancreatic (bp)- DNase I in Saccharomyces cerevisiae and Pichia pastoris. The bp-DNase I gene was fused in frame with the GAL10 promoter, $MF{\alpha}$, and GAL7 terminator sequences, resulting in the plasmid, pGAL-$MF{\alpha}$-DNaseI (6.4 kb). Also, the bp-DNase I gene was fused in frame with the AOX1 promoter, $MF{\alpha}$, and AOX1 terminator sequences, resulting in the plasmid, pPEXI (8.8 kb). The recombinant plasmids, pGAL-$MF{\alpha}$-DNaseI and pPEXI were introduced into S. cerevisiae and P. pastoris host cells, respectively. When the transformed yeast cells were cultured at $30^{\circ}C$ for 48 h in galactose or methanol medium, bp-DNase I was overexpressed and the most of activity was found in the extracellular fraction. P. pastoris transformant activity showed 45.5 unit/mL in the culture medium at 48 h cultivation, whereas S. cerevisiae transformant revealed 37.7 unit/mL in the extracellular fraction at 48 h cultivation. The enzymatic characteristics, such as DNA cleavage and half life were investigated. Treatment of the recombinant DNase I from P. pastoris induced degradation of the calf thymus DNA within 1 minute, and this DNA degradation rate was higher than that of commercial bp-DNase I (SIGMA) and the recombinant DNase I from S. cerevisiae.

• Preventive Nutrition and Food Science
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• v.21 no.1
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• pp.62-67
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• 2016

Green tea (Camellia sinensis) is one of the most popular beverages in the world and has been acknowledged for centuries as having significant health benefits. (-)-Epigallocatechin-3-gallate (EGCG) is the most abundant catechin in green tea, and it has been reported to have health benefit effects. Peroxisome proliferator-activated receptor ${\gamma}$ coactivator $(PGC)-1{\alpha}$ is a crucial regulator of mitochondrial biogenesis and hepatic gluconeogenesis. The objective of this study was to investigate whether EGCG from green tea can affect the ability of transcriptional regulation on $PGC-1{\alpha}$ mRNA expression in HepG2 cells and 3T3-L1 adipocytes. To study the molecular mechanism that allows EGCG to control $PGC-1{\alpha}$ expression, the promoter activity levels of $PGC-1{\alpha}$ were examined. The $PGC-1{\alpha}$ mRNA level was measured using quantitative real-time PCR. The -970/+412 bp of $PGC-1{\alpha}$ promoter was subcloned into the pGL3-Basic vector that includes luciferase as a reporter gene. EGCG was found to up-regulate the $PGC-1{\alpha}$ mRNA levels significantly with $10{\mu}mol/L$ of EGCG in HepG2 cells and differentiated 3T3-L1 adipocytes. $PGC-1{\alpha}$ promoter activity was also increased by treatment with $10{\mu}mol/L$ of EGCG in both cells. These results suggest that EGCG may induce $PGC-1{\alpha}$ gene expression, potentially through promoter activation.

• Korean Journal of Animal Reproduction
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• v.16 no.2
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• pp.141-147
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• 1992

The present study was conducted to find out the changes of progesterone and 20$\alpha$-dihydroprogesterone(20$\alpha$-OHP) levels during the gestation period in Korean native goats. 4 pregnant goats were offered for this experiment. Blood samples were taken from jugular vein on Day 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140 and 145 of the pregnant goats. The serum levels of progesterone and 20$\alpha$-OHP were measured by radioimmunoassay. The progesterone level in goat serum during the gestaton was low as 2.94$\pm$0.21 at 5 days, and then increased to 4.51$\pm$0.25ng/ml at 10 days of gestation and increased greatly from Days 60 and reached a peak level of 7.21$\pm$0.58ng/ml at 100 days of gestation, and thereafter decreased to 6.01$\pm$0.57, 5.26$\pm$0.64ng/ml on Days 130, 140 of gestation, and decreased to 4.05$\pm$0.52ng/ml on Days 145 of pregnancy. The serum level of 20$\alpha$-OHP during the gestation was low as 0.3~0.4ng/ml in the early stage of pregnancy, and increased gradually and increased to 0.85$\pm$0.06ng/ml, 0.97$\pm$0.08ng/ml on Days 90 or 100, and then increased to 1.18$\pm$0.18, 1.25$\pm$0.21ng/ml on Days 140 or 145 of gestation. While the serum levels of progesterone during the luteal regression decreased, the 20$\alpha$-OHP increased continuously. From the above results, it was concluded that the enzyme 20$\alpha$-hydroxysteroid dehydrogenase (20$\alpha$-HSD) catalyzing theconversion of progesterone to a biologically inactive steroid, 20$\alpha$-OHP was active properly in the luteal cells what the levels of progesterone decreased and the levels of 20$\alpha$-OHP increased during the late pregnancy in Korean native goats.

• 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.

• Archives of Pharmacal Research
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• v.21 no.3
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• pp.361-362
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• 1998