• Asian-Australasian Journal of Animal Sciences
• /
• v.32 no.5
• /
• pp.629-636
• /
• 2019

Objective: The study was designed to determine the cytotoxic effect of gallic acid (GA), obtained by the hydrolysis of tannins, on mice TM4 Sertoli cells apoptosis. Methods: In the present study, non-tumorigenic mice TM4 Sertoli cells were treated with different concentrations of GA for 24 h. After treatment, cell viability was evaluated using WST-1, mitochondrial dysfunction, cells apoptosis and necrosis was detected using JC-1, Hoechst 33342 and propidium iodide staining. The expression levels of Cyclin B1, proliferating cell nuclear antigen (PCNA), Bcl-2-associated X protein (BAX), and Caspase-3 were also detected by quantitative real-time polymerase chain reaction and Western-blotting. Results: The results showed that 20 to $400{\mu}M$ GA inhibited viability of TM4 Sertoli cells in a dose-dependent manner. Treatment with $400{\mu}M$ GA significantly inhibited PCNA and Cyclin B1 expression, however up-regulated BAX and Caspase-3 expression, caused mitochondrial membrane depolarization, activated Caspase-3, and induced DNA damage, thus, markedly increased the numbers of dead cells. Conclusion: Our findings showed that GA could disrupt mitochondrial function and caused TM4 cells to undergo apoptosis and necrosis.

• Journal of Korean Medicine for Obesity Research
• /
• v.19 no.1
• /
• pp.1-11
• /
• 2019

Objectives: The purpose of the present study was to evaluate the preventive effects of ethanol extract of Polygalae radix (EEPR) against oxidative stress (hydrogen peroxide, $H_2O_2$)-induced DNA damage and apoptosis in Chang liver cells. Methods: Chang liver cells were pretreated with various concentrations of EEPR and then challenged with 0.5 mM $H_2O_2$. The cell viability and apoptosis were assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and flow cytometry analysis, respectively. The levels of reactive oxygen species (ROS), mitochondrial membrane potentials (MMPs) and adenosine tri-phosphate (ATP) contents were measured. Expression levels of Bcl-2 and Bax were also determined using Western blot analysis. Results: The results showed that the decreased survival rate induced by $H_2O_2$ could be attributed to the induction of DNA damage and apoptosis accompanied by the increased production of ROS, which was remarkably protected by EEPR. In addition, the loss of $H_2O_2$-induced MMPs and ATP contents was significantly attenuated in the presence of EEPR. The inhibitory effect of EEPR on $H_2O_2$-induced apoptosis was associated with up-regulation of Bcl-2 and down-regulation of Bax, thus reducing the Bax/Bcl-2 ratio. Conclusions: Our data prove that EEPR protects Chang liver cells against $H_2O_2$-induced DNA damage and apoptosis by scavenging ROS and thus suppressing the mitochondrial-dependent apoptosis pathway.

• Transactions of the Korean hydrogen and new energy society
• /
• v.18 no.4
• /
• pp.432-438
• /
• 2007

The reforming process for hydrogen production generates some impurities. Impurities in hydrogen such as $CO_2$, CO, $H_2S$, $NH_3$ affect fuel cell performance. It is well known that CO generated by the reforming process may negatively affect performance of cell, cause damage on catalysts resulting performance degradation. Hydrogen produced by reforming process includes about 2% methane. The presence of methane up to 10% is reported negligible degradation in cell performance. However, methane more than 10% in hydrogen stream had not been researched. The concentration of impurity supplied to the fuel cell was verified by gas chromatography(GC). In this study, the influence of $CH_4$ on performance of PEM fuel cell was investigated by means of current vs. potential experiment, long run(10 hr) test and electrochemical impedance measurement when the concentrations of impurities were 10%, 20% and 30%.

• Transactions of the Korean hydrogen and new energy society
• /
• v.23 no.5
• /
• pp.468-475
• /
• 2012

A proper stacking force and assembly are important to the performance of fuel cell. Improper assembly pressure may lead to leakage of fuels and high interfacial contact resistance, excessive assembly pressure may result in damage to the gas diffusion layer and other components. The pressure distribution of gas diffusion layer is important to make interfacial contact resistance less for stack performance. To analyze the influence of design parameter factors for pressure distribution, and to optimize stack design, DOE (Design of Experiment) was used for polymer electrolyte membrane fuel cell stack pressure test. As commonly known, the higher clamping force improves the fuel cell stack performance. However, non-uniformity of stress distribution is also increased. It shows that optimization between clamping force and stress distribution is needed for well designed structure of fuel cell stack. In this study, stack design optimization method is suggested by using FEM (Finite Element Methode) and DOE for light-weighted fuel cell stack.

• Journal of Biomedical Engineering Research
• /
• v.28 no.5
• /
• pp.684-693
• /
• 2007

Previous trials for development of a pulsatile-Extracorporeal Life Support had some defects such as insufficient blood flow, high pressure at its membrane oxygenator and the high risk of blood cell damage. To solve those problems of previous pulsatile-ECLSs, we suggest dual pulsatile blood pump structure for the new pulsatile-ECLS. Two pulsatile pumps areconnected in a parallel manner and this new structure raises the inflow capacity and efficiency and it decreases the high blood pressure at membrane oxygenator. In in-vitro experiments, The Energy Equivalent Pressure Increment(EEP inc.) was 10%, and it showed that its pulsatilty was $5{\sim}10$ times higher than other commercial ECLS In in-vivo experiments, we had applied a new pulsatile-ECLS to 30 Kg pigs and a new pulsatile-ECLS couldsupport high blood flow and pulsatility above 2 L/min, 10% EEP inc.

• BMB Reports
• /
• v.38 no.5
• /
• pp.507-516
• /
• 2005

Antimicrobial peptides (AMPs) have been isolated and characterized from tissues and organisms representing virtually every kingdom and phylum. Their amino acid composition, amphipathicity, cationic charge, and size allow them to attach to and insert into membrane bilayers to form pores by 'barrel-stave', 'carpet' or 'toroidal-pore' mechanisms. Although these models are helpful for defining mechanisms of AMP activity, their relevance to resolving how peptides damage and kill microorganisms still needs to be clarified. Moreover, many AMPs employ sophisticated and dynamic mechanisms of action to carry out their likely roles in antimicrobial host defense. Recently, it has been speculated that transmembrane pore formation is not the only mechanism of microbial killing by AMPs. In fact, several observations suggest that translocated AMPs can alter cytoplasmic membrane septum formation, reduce cell-wall, nucleic acid, and protein synthesis, and inhibit enzymatic activity. In this review, we present the structures of several AMPs as well as models of how AMPs induce pore formation. AMPs have received special attention as a possible alternative way to combat antibiotic-resistant bacterial strains. It may be possible to design synthetic AMPs with enhanced activity for microbial cells, especially those with antibiotic resistance, as well as synergistic effects with conventional antibiotic agents that lack cytotoxic or hemolytic activity.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• v.29 no.1
• /
• pp.1-15
• /
• 2016

Objective : For various reasons, Obesity & Rhinitis are constantly rising. So Interest of treatment has been expanding. We want to verify The Chungyeol (fire extinguishing) Lisup (Draining) effect of Bangpungtongsungsan on obese model of allergy rhinitis.Material and Methods : BALB/c mouse were divided four groups: control(CON), allergic induction(ARE), Bangpungtongsungsan extract administration(BTT), Bangpungtongsungsan double concentration extract administration (BT2T). Every group except control group were caused allergic rhinitis by Ovalbumin. BTT & BT2T were orally administered the Bangpungtongsungsan for 21days. Since then we observed the liver tissue cell and the nasal mucous membrane.Results : In comparison with ARE, experimental groups show relief of the nasal mucous membrane damage(secretion of mucus decrease, Itching decrease), Th2 eruption control(IL-4 decline), effect of anti-inflamatory(reducing TNF-α creation, decreasing of iNOS through NF-κB activation-inhibition). In addition, experimental groups show a loss in weight, diminished accumulation of fat. (decreasing within liver tissue, reducing TNF-α creation) BT2T is more effective to BTT.Conclusion : Bangpungtongsungsan treat obese model on allergy rhinitis thereby control fat augmentation, relieving inflammation.

• Journal of Life Science
• /
• v.17 no.2 s.82
• /
• pp.230-234
• /
• 2007

Oxygen is required for many important aerobic cellular reactions, it may undergo electrontransfer reactions, which generate highly reactive membrane-toxic intermediates (reactive oxygen species, ROS), such as hydrogen peroxide, singlet oxygen, superoxide radical, hydroxyl radical, hydroperoxyl radical, hydroxy ion. Various mechanisms are available to protect cells against damage caused by oxidative free radicals, including scavenging enzyme systems such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). This antioxidant defense system is a very complex and finely tuned system consisting of enzymes capable of detoxifying oxygen radicals as well as low molecular weight antioxidants. In addition, repair and turnover processes help to minimize subcellular damage resulting from free radical attack. $H_2O_2$,one of the major ROS, is produced at a high rate as a product of normal aerobic metabolism. The primary cellular enzymatic defense systems against $H_2O_2$ are the glutathione redox cycle and catalase. From Northern blot analysis of total RNAs from cultured cell with $H_2O_2$ treatment, various results were obtained. Expression of Cu/Zn SOD decreased when cell passage increased, but the level of the Cu/Zn SOD was scarcely expressed in 35 passage.

• Korean Journal of Bronchoesophagology
• /
• v.6 no.1
• /
• pp.29-37
• /
• 2000

Background and Objectives : The concentration of sulfur dioxide($SO_2$) gas in the ambient air appears increasing in the industry and urban area day by day. It was known that $SO_2$ is noxious gas. $SO_2$ can be irritating to the eyes, nose, throat, upper respiratory tract and skin. It produces sulfurous acid on contact with water and is extremely irritating to the nasopharynx and respiratory tract. Laminin is a family of extracellular matrix glycoproteins localized in the basement membrane that separates epithelial cells from the underlying stroma. The biological activities of laminin are to promote cell migration, wound healing, growth and differentiation. Meterials and Methods : The histologic changes and the expression of laminin in tracheal mucosa sacrificed at every weeks (to 7 weeks) after continued $SO_2$ exposure of 250ppm for 30 minutes a day were studied in rats. Results : Pathologic tissue was formed at the tracheal mucosa and the underlying tissue by the infiltration of monocytes and epithelium was transformed to the single cell layered epithelium above 5 weeks after exposure. At the 6 weeks after exposure, epithelial cells were partially lost and epithelial cell layer was transformed to be leaf-shaped. Submucosal tissue was transformed to be lymphatic tissue. An intense positive staining for laminin was found in apical cytoplasm and lateral surface of the normal epithelial cells and basement membrane but at the 5 and 6 weeks after exposure, laminin activity was decreased to the moderate activity. At the 7 weeks after exposure, laminin activity was decreased to the weak activity. Conclusion : Our finding suggests that $SO_2$ makes histologic damage on the tracheal mucosa and decreases immunoreactivity for laminin. Longer duration of the exposure of $SO_2$ makes more histologic damage on the tracheal mucosa and decreases immunoreactivity for laminin.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.28 no.1
• /
• pp.71-79
• /
• 2002

In the aged skin especially in the face and eyelid, deep and slight wrinkles are one of the remarkable phenomena of aging and the cause of wrinkle is various. Among the cause of wrinkles an oxidative stress plays an important roles in wrinkle formation process. It caused the lipid peroxidation of cell membrane, the increase of the MMPs(MatrixMetalloProteinase) gene expression and cellular DNA damage. These ROS induced materials may cause the degradation of collagen matrix system in the dermis and cause the formation of skin wrinkle. So, it is very important for protecting skin wrinkle formation to regulate ROS activity. In this study, we developed one active ingredient having multi functional activities such as activation of collagen synthesis, inhibition of MMPs activity, lipid peroxidation and free radical scavenging activity and inhibition of free radical induced DNA damage in vitro. Pericarpium castaneae extracts showed collagen synthesis increase in Normal Human Fibroblast and the inhibition of elastase activity (IC$\_$50/ of Elastase: 43.9$\mu\textrm{g}$/㎖). It showed also anti-oxidative activity (IC$\_$50/ : 48$\mu\textrm{g}$/㎖) and free radical scavenging activity(IC$\_$50/: 7.6$\mu\textrm{g}$/㎖). Conclusively, Pericarpium castaneae extracts may be used as an ingredient for new anti-wrinkle cosmetics.