• Korean Journal of Plant Resources
• /
• v.22 no.5
• /
• pp.477-482
• /
• 2009

Inhibitory effect of skin and seed of three species grape cultivated in Korea on melanogenesis was investigated. Melanin generation was examined in $\alpha$-Melanin Stimulating Hormone-stimulated B16 cell, mouse melanoma, in the presence of samples. All skin sample did not show the inhibitory effect. Seed extract of Campbell early and Neo Muscat had negative effect on cell viability. When $50{\mu}g/ml$ seed extract of Muscat Bailey A was treated, amount of generated melanin and cell viability were $51.6{\pm}20.5%$ and $90.4{\pm}11.3%$ compared to control, respectively. Seed extract of Muscat Bailey A reduced the tyrosinase protein induced by $\alpha$-Melanin Stimulating Hormone, which suggests that inhibitory effect of seed extract of Muscat Bailey A on melanin is partly due to suppression of tyrosinase that is responsible for melanin production.

• Clinical and Experimental Reproductive Medicine
• /
• v.39 no.2
• /
• pp.73-80
• /
• 2012

Objective: This study was undertaken to determine the effect of hypoxia inducible factor (HIF)-$1{\alpha}$ on the cell death, autophagy, and invasion of trophoblasts. Methods: To understand the effect of HIF-$1{\alpha}$, we inhibited HIF-$1{\alpha}$ using siRNA under normoxia and hypoxia conditions. Invasion assay and zymography were performed to determine changes in the invasion ability of HIF-$1{\alpha}$. Western blotting and immunofluorescence were performed to determine some of the signal events involved in apoptosis and autophagy. Results: There was no difference in cell death through the inhibition of HIF-$1{\alpha}$ expression by siRNA; however, the expression of LC3 and autophagosome formation increased. On the other hand, autophagy was increased, and the invasive ability of trophoblast cells decreased according to the inhibition of HIF-$1{\alpha}$ expression by siRNA. These experimental results mean that HIF-$1{\alpha}$ genes regulate the invasive ability of trophoblasts by increasing autophagy. Conclusion: This study contributes important data for understanding the mechanism of early pregnancy implantation and the invasive ability of trophoblasts by defining the relationship between the roles of HIF-$1{\alpha}$ and autophagy.

• Journal of the Korean Ceramic Society
• /
• v.25 no.5
• /
• pp.465-472
• /
• 1988

Alpha alumina powder with fine particle size and narrow particle size distribution was prepared by precipitation method using Al2(SO4)3.18H2O as a starting material. The alpha alumina powder was prepared by calcining aluminum hydroxide which was formed under various pH values. The sinterabilityof alpha alumina powder and the effect of MgO on the sinterability of alpha alumina powder were investigated. The sinterability of alpha alumina powder was the order of pH=10≒pH11>pH=7≒pH9, and alpha alumina obtained from boehmite which was prepared by precipitation method reached to 97.5% of theoretcal density by the pressureless sintering. The effect of MgO on volume shrinkage of alumina was very slight in the initial sintering stage but remarkable in the final sintering stage. It was also found that MgO controlled effectively the grain growth of alumina.

• Journal of Periodontal and Implant Science
• /
• v.40 no.3
• /
• pp.119-124
• /
• 2010

Purpose: In addition to regulating body weight, leptin is also recognized for its role in the regulation of immune function and inflammation. The purpose of this study was to investigate the effect of leptin on Prevotella (P.) intermedia lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-$\alpha$ production in differentiated THP-1 cells, a human monocytic cell line. Methods: LPS from P. intermedia ATCC 25611 was prepared by the standard hot phenol-water method. THP-1 cells were incubated in the medium supplemented with phorbol myristate acetate to induce differentiation into macrophage-like cells. The amount of TNF-$\alpha$ and interleukin-8 secreted into the culture medium was determined by enzyme-linked immunosorbent assay (ELISA). TNF-$\alpha$ and Ob-R mRNA expression levels were determined by semi-quantitative reverse transcription-polymerase chain reaction analysis. Results: Leptin enhanced P. intermedia LPS-induced TNF-$\alpha$ production in a dose-dependent manner. Leptin modulated P. intermedia LPS-induced TNF-$\alpha$ expression predominantly at the transcriptional level. Effect of leptin on P. intermedia LPS-induced TNF-$\alpha$ production was not mediated by the leptin receptor. Conclusions: The ability of leptin to enhance P. intermedia LPS-induced TNF-$\alpha$ production may be important in the establishment of chronic lesion accompanied by osseous tissue destruction observed in inflammatory periodontal disease.

• Preventive Nutrition and Food Science
• /
• v.17 no.1
• /
• pp.8-13
• /
• 2012

This study was designed to investigate whether Sargassum ringgoldianum extract may inhibit ${\alpha}$-glucosidase and ${\alpha}$-amylase activities, and alleviate postprandial hyperglycemia in streptozotocin-induced diabetic mice. The $IC_{50}$ values of Sargassum ringgoldianum extract against ${\alpha}$-glucosidase and ${\alpha}$-amylase were 0.12 mg/mL and 0.18 mg/mL, respectively, which evidenced higher activities than those of acarbose. The blood glucose levels of the Sargassum ringgoldianum extract administered group were significantly lower compared to the control group in the streptozotocin-induced diabetic mice. Moreover, the area under the two-hour blood glucose response curve was significantly reduced and the absorption of dietary carbohydrates was delayed after administration of Sargassum ringgoldianum extract in the diabetic mice. Therefore, these results indicated that Sargassum ringgoldianum extract may help decrease the postprandial blood glucose level via inhibiting ${\alpha}$-glucosidase.

• Natural Product Sciences
• /
• v.10 no.5
• /
• pp.223-227
• /
• 2004

This study was carried out to investigate inhibitory effect of extracts from the root of Paeonia lactiflora on postprandial hyperglycemia. Organic solvent (hexane, ethyl acetate, butanol, aqueous) extracts from the crude drug were fractionated by high performance liquid chromatography. These fractions were examined to evaluate ${\alpha}-glucosidase$ (EC 3. 2. 1. 20) inhibition by microplate colorimetric assay. Among the fractions examined, the ethyl acetate fraction from the roots of Paeonia lactiflora showed potent inhibitory effects on ${\alpha}-glucosidase$. Therefore, further fractionation of the fraction was carried out to isolate the active principles. Finally, we isolated and Purified 1,2,3,4,6-penta-O-galloyl-beta-D-glucose (PGG) as a active principle by activity-guided fractionation. These results suggest that the extract from the root of Paeonia lactiflora can be used as a new nutraceutial for inhibition on postprandial hyperglycemia and PGG might be a candidate for developing an ${\alpha}-glucosidase$ inhibitor.

• Clinical and Experimental Reproductive Medicine
• /
• v.26 no.1
• /
• pp.97-101
• /
• 1999

Male genital tract inflammatory conditions may be associated with unexplained infertility. The presence of cytokine such as tumor necrosis factor-alpha (TNF-${\alpha}$) was reported in the semen of infertile men. However, the effect of these cytokines on human sperm function is still unclear. The purpose of this study was to investigate the in-vitro effects of TNF-alpha on human sperm motility with computer assisted sperm analysis. Washed sperm from 16 normal men were incubated without and with TNF-${\alpha}$ (0.1, 10, 1000 ng/ml). The changes of parameters of sperm motility were recorded at different time intervals (0, 5, 24 hour). There was no significant change of parameters of sperm motility in the incubation with TNF-${\alpha}$. It is suggested that TNF-${\alpha}$ alone does not interfere with the sperm motility and more studies are needed.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.24 no.6
• /
• pp.956-961
• /
• 2010

Tumor necrosis factor-alpha (TNF-${\alpha}$) is a major mediator of immuno-inflammatory activity. The purpose of this study is to investigate whether TNF-${\alpha}$ productions of mouse macrophage RAW 264.7 and human hepatocyte HepG2 are modulated by Artemisiae argi Folium water extract (AW), Lactobacillus pentosus-fermented Artemisiae argi Folium water extract (AFL), and Saccharomyces cerevisiae-fermented Artemisiae argi Folium water extract (AFS) for 3 h of incubation. Effect of AW on cell viability of HepG2 was also investigated. TNF-${\alpha}$ productions were measured by Enzyme-Linked Immnunosorbent Assay method and cell viability was measured by MTT assay. Both AFL and AFS significantly increased TNF-${\alpha}$ productions of RAW 264.7 at the concentration of 50, 100, and 200 ${\mu}g$/mL (p<0.05). Also, AFL and AFS significantly increased TNF-${\alpha}$ productions of HepG2 at the concentration of 50, 100, and 200 ${\mu}g$/mL (p<0.05). AW significantly increased TNF-${\alpha}$ production of HepG2 at the concentration of 100 and 200 ${\mu}g$/mL (p<0.05). AW did not show any cytotoxicity on HepG2 cells for 3 h. These results suggest that AFL, AFS, and AW have the immune-enhancing property related with its increasing effect on TNF-${\alpha}$ production of macrophage and hepatocyte.

• Korean Journal of Pharmacognosy
• /
• v.29 no.1
• /
• pp.8-12
• /
• 1998

$3{\alpha}-Hydroxysteroid$ dehydrogenase $(3{\alpha}-HSD)$ is one of the main enzymes involved in the metabolism of the active androgen, dihydrotestosterone. The NAD(P)-linked $3{\alpha}-HSD$ of rat liver cytosol is powerfully inhibited by the non-steroidal anti-inflammatory drugs in rank-order of their therapeutic potency. This observation has now been developed into a rapid screen for predicting the potency of products that show anti-inflammatory effect. 52-Chinese Herbs that clear heat were screened by using this method.

• Biomedical Science Letters
• /
• v.19 no.2
• /
• pp.118-123
• /
• 2013

Tumor necrosis factor-alpha (TNF-${\alpha}$) is a proinflammatory cytokine that mediates the inflammatory response and immune functions, and modulates the proliferation, differentiation and cell death of cancer cells. The differential functions of TNF-${\alpha}$ in various human cells due to the formation of different stimulating pathway upon the binding of TNF-${\alpha}$ to its receptors. In the present study, we examined the different effects of TNF-${\alpha}$ on the survival and apoptosis between normal granulocytes and human myeloid leukemia HL-60 cells. Although TNF-${\alpha}$ did not affect on the constitutive apoptosis of granulocytes, TNF-${\alpha}$ strongly induced the apoptosis of HL-60 cells in a dose- and a time-dependent manner. TNF-${\alpha}$-induced apoptosis was occurred via the activation of caspase 8, caspase 9 and caspase 3/7 and the induction of ROS production in HL-60 cells. Also, BAY-11-7085, a NF-${\kappa}B$ inhibitor, blocked the TNF-${\alpha}$-induced apoptosis in HL-60 cells. NF-${\kappa}B$ may be involved in TNF-${\alpha}$-induced apoptotic signaling pathway in HL-60 cells. These results suggest that TNF-${\alpha}$ activates apoptotic pathways and its process depends on cell type and many cellular factors. A better understanding of the differential effect of TNF-${\alpha}$ on cell apoptosis and survival may provide important information that can be used to elucidate the specific inhibitory effect of TNF-${\alpha}$ on the cancer dis.