• The Korean Journal of Physiology and Pharmacology
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• 제20권2호
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• pp.221-228
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• 2016

We investigated whether prunetin affects the proteolytic activity, secretion, and gene expression of matrix metalloproteinase-3 (MMP-3) in primary cultured rabbit articular chondrocytes, as well as in vivo production of MMP-3 in the rat knee joint to evaluate the potential chondroprotective effect of prunetin. Rabbit articular chondrocytes were cultured in a monolayer, and reverse transcriptionpolymerase chain reaction (RT-PCR) was used to measure interleukin-$1{\beta}$ (IL-$1{\beta}$)-induced expression of MMP-3, MMP-1, MMP-13, a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4), and ADAMTS-5. In rabbit articular chondrocytes, the effects of prunetin on IL-$1{\beta}$-induced secretion and proteolytic activity of MMP-3 were investigated using western blot analysis and casein zymography, respectively. The effect of prunetin on MMP-3 protein production was also examined in vivo. The results were as follows: (1) prunetin inhibited the gene expression of MMP-3, MMP-1, MMP-13, ADAMTS-4, and ADAMTS-5; (2) prunetin inhibited the secretion and proteolytic activity of MMP-3; (3) prunetin suppressed the production of MMP-3 protein in vivo. These results suggest that prunetin can regulate the gene expression, secretion, and proteolytic activity of MMP-3, by directly acting on articular chondrocytes.

• 약학회지
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• 제48권6호
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• pp.358-363
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• 2004

Matrix metalloproteinases (MMPs) are known to play an important role in photoaging by mediating the degradation of extracellular matrix proteins. In this study, to develop a n ew anti-aging agent, we investigated the antioxidant activity and the inhibitory effect of Melothria heterophylla extract on expression of MMP-1 in UVA-irradiated human dermal fibroblasts and MMP-1 activity. The M.heterophylla extract was found to scavenge radicals and reactive oxygen species (ROS) with the $SC_{50}$ values of $13{\mu}g/ml$ against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and $20{\mu}g/ml$ against superoxide radicals in the xanthine/xanthine oxidase system, respectively. UVA-induced MMP-1 expression was reduced about 80% by $100{\mu}g/ml$ of the M.heterophylla extract but MMP-1 Mrna expression was not inhibited. Therefore, we conclude that the M.heterophylla extract significantly inhibits MMP-1 expression at the protein level. Also, the M.heterophylla extract inhibited MMP-1 activity in a dose dependent manner. From these results, we suggest that the M.heterophylla extract can be used as a new anti-aging agent by antioxidant activity, regulation of UVA-induced MMP-1 production, and inhibition of MMP-1 activity.

• KSBB Journal
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• 제28권2호
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• pp.137-145
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• 2013

In order to develop new skin whitening agents, we prepared the $CH_2Cl_2$ layer (NGC) and BuOH layer (NGB) of 75% EtOH extract of the Nelumbinis nucifera Gaertner. We measured their tyrosinase inhibitory activity in vitro and melanin synthesis inhibitory activity in B16-F1 melanoma cells. They did not show inhibitory activity against mushroom tyrosinase but showed melanin synthesis inhibitory activity in a dose-dependent manner. In a melanin synthesis inhibition assay, NGC and NGB suppressed melanin production up to 52% and 46% at a concentration of $100{\mu}g/mL$, respectively. To elucidate the mechanism of the inhibitory effects of NGC and NGB on melanogenesis, we measured the expression of melanogenesis-related proteins by western blot assay. As a result, NGC suppressed the expression of tyrosinase, tyrosinase related protein 1 (TRP-1), tyrosinase related protein 2 (TRP-2), phosphorylated cAMP responsive element binding (p-CREB) protein, and microphthalmia associated transcription factor (MITF). And NGB inhibited the protein expression of tyrosinase and MITF, but had no significant effect on TRP-1, TRP-2, and p-CREB expression. Moreover, NGB increased the expression of phosphorylated extracellular signal-regulated kinase (p-ERK). In addition, we examined the inhibitory effect on the glycosylation of tyrosinase. As a result, NGC and NGB inhibited the activity of ${\alpha}$-glucosidase in vitro and the glycosylation of tyrosinase in B16-F1 melanoma cells. From these results, we concluded that NGC and NGB could be used as active ingredients for skin whitening.

• 한국잠사학회:학술대회논문집
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• 한국잠사학회 1997년도 Progress and Future Development of Sericultural Science and Technology 40th Anniversary Commemoration Symposium
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• pp.51-72
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• 1997

Diapause hormone (DH) is a neuropeptide hormone which is secreted from the suboesophageal ganglion (SG) and is responsible for induction of embryonic diapause of the silkworm, Bombyx mori. DH is isolated from SGs and determined to be a 24 amino acid peptide amide. The cDNA encodes the polyprotein precursor from which DH, pheromone biosynthesis activating neuropeptide (PBAN) and three other neuropeptides are released and become matured. The C-terminal FXPRL-NH2 sequence of DH is essential but not sufficient for expression of full activity. Recently, we have isolated a unique hydrohobic peptide (VAP peptide) with a slight diapause egg induceing activity from organic solvent extracts of the male adult heads of the silkworm. The VAP peptide itself has no diapause inducing activity, but enhances DH activity through reducing ED50 value and the threshold concentration of DH. The DH-PBAN gene is composed of 6 exons interrupted by 5 introns and is expressed in 12 neurosecretory cells of the SG. The incubation of eggs at 25$^{\circ}C$, which induces embryonic diapause in the progeny, caused DH-PBAN mRNA content to increase at 5 different stages in the life cycle. By contrast, a 15$^{\circ}C$ incubation only induced expression of the gene at the late phrase adult stage. The temperature-controlled expression of DH-PBAN gene is closely correlated to the incidence of diapause, indicating that DH-PBAN gene expression is the initial event leading to diapause induction. DH acts to stimulate trehalase activity in developing ovary to bring about hyprglycogenism in mature eggs, a prerequisite metabolism for diapause initiation. Using in vivo and in vitro systems, DH is clearly shown to induce trehalase gene expression in developing ovaries. New protein synthesis is not needed for this process, but a Ca2+-dependent proteinkinase seems to be involved. Quite recently, we have sucessfully applied a new and potent trehalase inhibitor (Trehazoline) to reudce glycogen content in developing ovaries. The eggs deficient in glycogen were also able to enter diapause as the natural eggs do, so that we could provide the new egg system to reconsider the diapause associated metabolism other than the glycogen-sorbitol metabolic system.

• 대한의생명과학회지
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• 제15권4호
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• pp.355-362
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• 2009

I evaluated the protective effect of N-methyl-D-aspartate (NMDA)/glycine receptor antagonist, 7-chlorokinurenic acid (CKA) on cultured mouse astrocytes damaged by ischemia-like condition (ILC). The protective effect of CKA was assessed by cell viability, lactate dehydrogenase (LDH) activity, superoxide dismutase (SOD)-like activity and lipid peroxidation. To examine the effect of CKA on the cell apoptosis, the expression and the activity of caspase 3 were assessed by Western blotting. CKA increased the cell viability decreased by ILC. CKA also decreased the LDH activity and antioxidative effects such as SOD-like activity and inhibitory activity of lipid peroxidation. In addition, CKA suppressed the expression of caspase 3 associated with apoptosis, and increased the cell viability by the decrease of caspase 3 activity as like the caspase 3 inhibitor, Av-DVED-MED. From these results, these results suggest that ILS induces cell cytotoxicity in cultured astrocytes and CKA, NMDA/glycine receptor antagonist, is effective on the prevention of the cytotoxicity due to ILS by the antioxidative effect and the inhibition of apoptosis.

• Biomolecules & Therapeutics
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• 제28권2호
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• pp.202-210
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• 2020

Fluoxetine is used widely as an antidepressant for the treatment of cancer-related depression, but has been reported to also have anti-cancer activity. In this study, we investigated the cytotoxicity of fluoxetine to human gastric adenocarcinoma cells; as shown by the MTT assay, fluoxetine induced cell death. Subsequently, cells were treated with 10 or 20 µM fluoxetine for 24 h and analyzed. Apoptosis was confirmed by the increased number of early apoptotic cells, shown by Annexin V- propidium iodide staining. Nuclear condensation was visualized by DAPI staining. A significant increase in the expression of cleaved PARP was observed by western blotting. The pan-caspase inhibitor Z-VAD-FMK was used to detect the extent of caspase-dependent cell death. The induction of autophagy was determined by the formation of acidic vesicular organelles (AVOs), which was visualized by acridine orange staining, and the increased expression of autophagy markers, such as LC3B, Beclin 1, and p62/SQSTM 1, observed by western blotting. The expression of upstream proteins, such as p-Akt and p-mTOR, were decreased. Autophagic degradation was evaluated by using bafilomycin, an inhibitor of late-stage autophagy. Bafilomycin did not significantly enhance LC3B expression induced by fluoxetine, which suggested autophagic degradation was impaired. In addition, the co-administration of the autophagy inhibitor 3-methyladenine and fluoxetine significantly increased fluoxetine-induced apoptosis, with decreased p-Akt and markedly increased death receptor 4 and 5 expression. Our results suggested that fluoxetine simultaneously induced both protective autophagy and apoptosis and that the inhibition of autophagy enhanced fluoxetine-induced apoptosis through increased death receptor expression.

• Asian-Australasian Journal of Animal Sciences
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• 제24권2호
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• pp.239-245
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• 2011

This study was conducted to determine the effects of excess vitamin A on alkaline phosphatase (ALP) activity, contents of calcium-binding protein (CaBP), bone gla-protein (BGP) in culture medium and CaBP mRNA expression in chicken osteoblasts in vitro. Osteoblastic cells in the tibia from 1-day-old Arbor Acre broiler chickens were isolated using enzyme digestion. The subconfluenced cells were divided into eight treatments with six replicates in each treatment and cultured in a medium containing either vehicle or different levels of vitamin A (0, 0.2, 0.6, 1.0, 2.0, 5.0, 10.0 and $20.0\;{\mu}g$/ml), and the control received an equivalent volume of ethanol. The incubation lasted 48 h. The results showed that vitamin A down-regulated ALP activity in the culture medium as well as CaBP mRNA expression of osteoblasts in a linear dose-dependent manner (p = 0.124 and p<0.10, respectively), and suppressed the contents of BGP and CaBP in the culture medium in a quadratic dose-dependent manner (p<0.05 and p<0.10, respectively) with increasing addition of vitamin A. The addition of 0-$0.2\;{\mu}g$/ml vitamin A to the culture medium increased ALP activity, BGP and CaBP contents as well as CaBP mRNA expression compared with other groups, but positive effects of vitamin A tended to be suppressed when vitamin A was increased to $1.0\;{\mu}g$/ml, and adverse effects occurred when vitamin A was increased to 10.0-$20.0\;{\mu}g$/ml. These results implied that there was a threshold level of vitamin A inclusion beyond which inhibitory effects occurred, and the mechanism by which overdose of vitamin A reduced bone growth in chickens was probably reduced osteoblastic cell activity, and inhibited expression of CaBP mRNA and CaBP secretion.

• 아동학회지
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• 제28권1호
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• pp.189-204
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• 2007

This research investigated the effect of story-plotting and oral narration activities using wordless picture books upon young children's linguistic creativity and expression. The subjects were 30 children of experimental group and another 30 in the control group at age five. The Korean Comprehensive Creativity Test for Young Children(K-CCTYC; Jeon, 2005) was used to measure linguistic creativity. In addition, Measure Tools for Linguistic Ability(Jang, 1981) was used to measure the linguistic expression. There were significant differences between the two groups in linguistic creativity including linguistic fluency, flexibility, and originality as well as linguistic expression.

• Molecular & Cellular Toxicology
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• 제2권4호
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• pp.223-228
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• 2006

Several plant-derived cannabinoids and endogenous ligands for cannabinoid receptors such as 2-arachidonyl-glycerol have been known to inhibit interleukin-2 (IL-2) expression. In the present study, we utilized arachidonylethanolamide (AEA), a putative endogenous ligand for cannabinoid receptors, to determine whether AEA modulated the expression of IL-2. AEA inhibited phorbol 12-myristate 13-acetate (PMA) plus ionomycin (Io)-induced IL-2 protein secretion and mRNA expression in EL-4 mouse T-cells as determined by ELISA and RT-PCR, respectively. To further characterize the inhibitory mechanism of AEA at the transcriptional level, we performed promoter study for IL-2 gene in PMA/Io-stimulated EL-4 cells. AEA decreased the transcriptional activity of the nuclear factor of activated T-cells (NF-AT) as well as the IL-2 promoter activity. These results suggest that AEA suppresses IL-2 expression and that the inhibition is mediated, at least in part, through the down-regulation of NF-AT.

• The Korean Journal of Physiology and Pharmacology
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• 제25권2호
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• pp.111-118
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• 2021

27-Hydroxycholesterol (27OHChol) exhibits agonistic activity for liver X receptors (LXRs). To determine roles of the LXR agonistic activity in macrophage gene expression, we investigated the effects of LXR inhibition on the 27OHChol-induced genes. Treatment of human THP-1 cells with GSK 2033, a potent cell-active LXR antagonist, results in complete inhibition in the transcription of LXR target genes (such as LXRα and ABCA1) induced by 27OHChol or a synthetic LXR ligand TO 901317. Whereas expression of CCL2 and CCL4 remains unaffected by GSK 2033, TNF-α expression is further induced and 27OHChol-induced CCL3 and CXCL8 genes are suppressed at both the transcriptional and protein translation levels in the presence of GSK 2033. This LXR antagonist downregulates transcript levels and surface expression of CD163 and CD206 and suppresses the transcription of CD14, CD80, and CD86 genes without downregulating their surface levels. GSK 2033 alone had no effect on the basal expression levels of the aforementioned genes. Collectively, these results indicate that LXR inhibition leads to differential regulation of 27-hydroxycholesterol-induced genes in macrophages. We propose that 27OHChol induces gene expression and modulates macrophage functions via LXR-dependent and -independent mechanisms.