• Journal of Microbiology and Biotechnology
• /
• v.17 no.2
• /
• pp.207-217
• /
• 2007

The Saccharomyces0 cerevisiae KNU5377 strain, which was isolated from spoilage in nature, has the ability to convert biomass to alcohol at high temperatures and it can resist against various stresses [18, 19]. In order to understand the defense mechanisms of the KNU5377 strain under menadione (MD) as oxidative stress, we used several techniques for study: peptide mass fingerprinting (PMF) by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MS) followed by two-dimensional (2D) gel electrophoresis, liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS), and surface-enhanced laser desorption ionization-time of flight (SELDI-TOF) technology. Among the 35 proteins identified by MALDI-TOF MS, 19 proteins including Sod1p, Sod2p, Tsa1p, and Ahp1p were induced under stress condition, while 16 proteins were augmented under normal condition. In particular, five proteins, Sod1p, Sod2p, Ahp1p, Rib3p, Yaf9p, and Mnt1p, were induced in only stressed cells. By LC-ESI-MS/MS analysis, 37 proteins were identified in normal cells and 49 proteins were confirmed in the stressed cells. Among the identified proteins, 32 proteins were found in both cells. Five proteins including Yel047cp and Met6p were only upregulated in the normal cells, whereas 17 proteins including Abp1P and Sam1p were elevated in the stressed cells. It was interesting that highly hypothetical proteins such as Ynl281wp, Ygr279cp, Ypl273wp, Ykl133cp, and Ykr074wp were only expressed in the stressed cells. SELDI-TOF analysis using the SAX2 and WCX2 chips showed that highly multiple-specific protein patterns were reproducibly detected in ranges from 2.9 to 27.0 kDa both under normal and stress conditions. Therefore, induction of antioxidant proteins, hypothetical proteins, and low molecular weight proteins were revealed by different proteomic techniques. These results suggest that comparative analyses using proteomics might contribute to elucidate the defense mechanisms of KNU5377 under MD stress.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 2007.11a
• /
• pp.153-158
• /
• 2007

Background: Naturally occurring antioxidants were used to regulate the skin damage caused by ultraviolet (UV) radiation because several antioxidants have demonstrated that they can inhibit wrinkle formation through prevention of matrix metalloproteinases (MMPs) and/or increase of collagen synthesis. We examined the effect of oral administration of the antioxidant mixture ("L-Skin Care") on UVB-induced wrinkle formation. In addition, we investigated the possible molecular mechanisms of photoprotection against UVB through inhibition of collagen-degrading MMP activity or through enhancing of pro collagen synthesis in mouse dorsal skin. Methods: Female SKH-l hairless mice were orally administrated "L-Skin Care" (test group) or vehicle (control group) for 10 weeks with UVB irradiation by three times a week. The intensity of irradiation was gradually increased from 30 to $180mJ/cm^2$. Microtopographic and histological assessments of the dorsal skins were carried out at the end of 10 weeks to evaluate wrinkle formation. Western blot analysis and EMSA were also carried out to investigate the changes in the balance of collagen synthesis and collagen degradation. Results: Our "L-Skin Care" significantly reduced UVB-induced wrinkle formation, accompanied by significant reduction of epidermal thickness, and UVB-induced hyperplasia, acanthosis and hyperkeratosis. Oral administration of "L-Skin Care" significantly prevented UVB-induced expressions of MMPs, mitogen-activated protein (MAP) kinases and activation of activator protein (AP)-1 transcriptional factor in addition to enhanced type I procollagen and transforming growth factor-$\beta$ (TGF-$\beta$) expression. Conclusion: Oral administration of "L-Skin Care" significantly inhibited wrinkle formation caused by chronic UVB irradiation through significant inhibition of UVB-induced MMP activity accompanied with enhancement of collagen synthesis.

• Journal of Convergence for Information Technology
• /
• v.9 no.12
• /
• pp.286-293
• /
• 2019

In this study, four types of retinol, retinyl palmitate, adenocin, and polytoxylate-dretinamide, which are the ingredients of the Ministry of Food and Drug Safety Notice, included in the study. also we looked at trends in research on Sciadopitys verticillata, Prunella vulgaris, Celosia cristata L., Brazilin, Persicaria hydropiper, Astragalus membranaceus Bunge, Forsythiae Fructus, Lithospermum root, Rheum undulatum L. and Cistanche deserticola Y. C. Ma a natural material that has the efficacy of antioxidant aging. The anti-aging study so far has been found to be centered mainly on collagen production and elastase synthesis inhibition mechanisms. However, given that the aging process of the skin is caused by various ageing processes, it is believed that anti-aging studies using safe and effective natural materials that can help the skin age with various mechanisms should be conducted.

• The Korean Journal of Physiology and Pharmacology
• /
• v.25 no.3
• /
• pp.177-187
• /
• 2021

Metabolic syndrome (MBS) is a widespread disease that has strongly related to unhealthy diet and low physical activity, which initiate more serious conditions such as obesity, cardiovascular diseases and type 2 diabetes mellitus. This study aimed to examine the therapeutic effects of morin, as one of the flavonoids constituents, which widely exists in many herbs and fruits, against some metabolic and hepatic manifestations observed in MBS rats and the feasible related mechanisms. MBS was induced in rats by high fructose diet feeding for 12 weeks. Morin (30 mg/kg) was administered orally to both normal and MBS rats for 4 weeks. Liver tissues were used for determination of liver index, hepatic expression of glucose transporter 2 (GLUT2) as well as both inflammatory and fibrotic markers. The fat/muscle ratio, metabolic parameters, systolic blood pressure, and oxidative stress markers were also determined. Our data confirmed that the administration of morin in fructose diet rats significantly reduced the elevated systolic blood pressure. The altered levels of metabolic parameters such as blood glucose, serum insulin, serum lipid profile, and oxidative stress markers were also reversed approximately to the normal values. In addition, morin treatment decreased liver index, serum liver enzyme activities, and fat/muscle ratio. Furthermore, morin relatively up-regulated GLUT2 expression, however, down-regulated NF-κB, TNF-α, and TGF-β expressions in the hepatic tissues. Here, we revealed that morin has an exquisite effect against metabolic disorders in the experimental model through, at least in part, antioxidant, anti-inflammatory, and anti-fibrotic mechanisms.

• Journal of Animal Science and Technology
• /
• v.63 no.2
• /
• pp.211-247
• /
• 2021

Livestock species experience several stresses, particularly weaning, transportation, overproduction, crowding, temperature, and diseases in their life. Heat stress (HS) is one of the most stressors, which is encountered in livestock production systems throughout the world, especially in the tropical regions and is likely to be intensified due to global rise in environmental temperature. The gut has emerged as one of the major target organs affected by HS. The alpha- and beta-diversity of gut microbiota composition are altered due to heat exposure to animals with greater colonization of pathogenic microbiota groups. HS also induces several changes in the gut including damages of microstructures of the mucosal epithelia, increased oxidative insults, reduced immunity, and increased permeability of the gut to toxins and pathogens. Vulnerability of the intestinal barrier integrity leads to invasion of pathogenic microbes and translocation of antigens to the blood circulations, which ultimately may cause systematic inflammations and immune responses. Moreover, digestion of nutrients in the guts may be impaired due to reduced enzymatic activity in the digesta, reduced surface areas for absorption and injury to the mucosal structure and altered expressions of the nutrient transport proteins and genes. The systematic hormonal changes due to HS along with alterations in immune and inflammatory responses often cause reduced feed intake and production performance in livestock and poultry. The altered microbiome likely orchestrates to the hosts for various relevant biological phenomena occurring in the body, but the exact mechanisms how functional communications occur between the microbiota and HS responses are yet to be elucidated. This review aims to discuss the effects of HS on microbiota composition, mucosal structure, oxidant-antioxidant balance mechanism, immunity, and barrier integrity in the gut, and production performance of farm animals along with the dietary ameliorations of HS. Also, this review attempts to explain the mechanisms how these biological responses are affected by HS.

• Journal of Microbiology and Biotechnology
• /
• v.31 no.12
• /
• pp.1615-1623
• /
• 2021

Picropodophyllotoxin (PPT), an epimer of podophyllotoxin, is derived from the roots of Podophyllum hexandrum and exerts various biological effects, including anti-proliferation activity. However, the effect of PPT on colorectal cancer cells and the associated cellular mechanisms have not been studied. In the present study, we explored the anticancer activity of PPT and its underlying mechanisms in HCT116 cells. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to monitor cell viability. Flow cytometry was used to evaluate cell cycle distribution, the induction of apoptosis, the level of reactive oxygen species (ROS), assess the mitochondrial membrane potential (Δψm), and multi-caspase activity. Western blot assays were performed to detect the expression of cell cycle regulatory proteins, apoptosis-related proteins, and p38 MAPK (mitogen-activated protein kinase). We found that PPT induced apoptosis, cell cycle arrest at the G1 phase, and ROS in the HCT116 cell line. In addition, PPT enhanced the phosphorylation of p38 MAPK, which regulates apoptosis and PPT-induced apoptosis. The phosphorylation of p38 MAPK was inhibited by an antioxidant agent (N-acetyl-L-cysteine, NAC) and a p38 inhibitor (SB203580). PPT induced depolarization of the mitochondrial inner membrane and caspase-dependent apoptosis, which was attenuated by exposure to Z-VAD-FMK. Overall, these data indicate that PPT induced G1 arrest and apoptosis via ROS generation and activation of the p38 MAPK signaling pathway.

• International Journal of Oral Biology
• /
• v.47 no.3
• /
• pp.41-48
• /
• 2022

Ulva compressa Linnaeus (UCL) is a green algae seaweed that performs photosynthesis and is used as a food material in some Asian regions including Korea. It is known to be the dominant species in copper ion-contaminated seas, and many studies on copper ion resistant mechanisms have been reported. UCL is known to have an excellent antioxidant effect, but limited information is available regarding its other physiological activities. In this study, we investigated the anticancer activity of 30% prethanol extracts of Ulva compressa Linnaeus (30% PeUCL) and the underlying mechanisms of its activity on human FaDu hypopharyngeal squamous carcinoma cells. The 30% PeUCL extracts suppressed FaDu cell viability without affecting normal cells (L929), as determined by MTT and viability assays. Furthermore, the 30% PeUCL extracts induced apoptosis, as determined by DAPI staining. The 30% PeUCL extracts inhibited colony formation effectively as well as wound-healing of FaDu cells, even at noncytotoxic concentrations. In addition, 30% PeUCL extracts induced apoptosis significantly through proteolytic cleavage of caspase-3, -7, and -9, and poly (ADP-ribose) polymerase, and by downregulation of Bcl-2 and upregulation of Bax in FaDu cells, as determined by Western blot analysis. Collectively, these results suggest that the inhibitory effect of 30% PeUCL extracts on the growth of oral cancer cells, colony formation and wound-healing may be mediated by caspase- and mitochondrial-dependent apoptotic pathways in human FaDu hypopharyngeal squamous carcinoma cells. Therefore, 30% PeUCL extracts can be administered as a natural chemotherapeutic drug for the treatment of human oral cancers.

• Tuberculosis and Respiratory Diseases
• /
• v.46 no.5
• /
• pp.636-644
• /
• 1999

Background : Tumor necrosis factor(TNF) has been considered as an important candidate for cancer gene therapy based on its potent anti-tumor activity. The mechanisms of TNF cytotoxicity are not clearly understood and some has reported that reactive oxygen species(ROS) might be associated with them, but there is controversy about antioxidant effect on TNF cytotoxicity. This study was designed to compare the TNF cytotoxicity after antioxidant pretreatment with that of control to evaluate the role of ROS in the mechanism of TNF cytotoxicity. Method : We compared the TNF cytotoxicies to WEHI164(murine fibrosarcoma cell line) and ME180(human cervix cancer cell line) after antioxidant pretreatment with those of control by MIT(dimethylthiazolyl-diphenyltetrazolium bromide) assay. Results : In the control group, the TNF cytotoxicities were $92.2{\pm}2.8%$(WEHI164) and $59.9{\pm}7.0%$(MEl80). In the TMTU(tetramethyl thiourea) pretreatment group, those were $91.4{\pm}3.7%$ and $74.6{\pm}7.0%$. In the PMZ(promethazine) pretreatment group, those were $90.2{\pm}2.5%$ and $62.5{\pm}5.7%$. In the BHT(butylated hydroxytoluene) pretreatment group, those were $93.2{\pm}1.3%$ and $66.3{\pm}6.1%$. So there was no reduction in TNF cytotoxicity after antioxidants pretreatment. Conclusion : The ROS may not have major role in the mechanisms of TNF cytotoxicity.

• Korean Journal of Poultry Science
• /
• v.49 no.4
• /
• pp.211-220
• /
• 2022

Poultry are exposed to extremely high levels of oxidative stress as a consequence of the excessive production of reactive oxygen species (ROS) induced by endogenous and exogenous stressors, such as high-stocking densities, thermal stress, environmental and feed contamination, along with factors associated with intensive breeding systems. Oxidative stress promotes lipid peroxidation, DNA damage, and inflammation, which can have detrimental effects on the health of birds. During the course of evolution, birds have developed antioxidant defense mechanisms that contribute to maintaining homeostasis when exposed to endogenous and exogenous stressors. The primary antioxidant defense systems are enzymatic and non-enzymatic in nature and play roles in protecting cells from ROS attack. Recently, plant flavonoids, which have been established to reduce oxidative stress, have been attracting considerable attention as potential feed additives. Flavonoids are a group of polyphenolic compounds that can be stabilized by binding structural compounds with ROS, and can promote the elimination of ROS by inducing the expression of antioxidant enzymes. However, although flavonoids can contribute to reducing lipid peroxidation and thereby enhance the antioxidant capacity of birds, they have low solubility in the gastrointestinal tract, and consequently, it is necessary to develop a delivery technology that can facilitate the effect intestinal absorption of these compounds. Furthermore, it is important to determine the dietary levels of flavonoids by assessing the exact antioxidant effects in the gastrointestinal tract wherein the concentrations of dietary flavonoids are highest. It is also necessary to examine the expression of transcriptional factors and vitagenes associated with the efficient antioxidant effects induced by flavonoids. It is anticipated that the application of flavonoids as natural antioxidants will become a particularly important field in the poultry industry.

• International Journal of Oral Biology
• /
• v.34 no.4
• /
• pp.205-213
• /
• 2009

The mechanisms underlying the actions of the antioxidants upon reactive oxygen species (ROS) generation by NADPH oxidase complex have remained uncertain. In this study, we investigated NADPH oxidase activity and the role of antioxidant enzymes upon the generation of ROS during hypoxic stress. ROS generation was found to increase in the mouse kidney under hypoxic stress in a time-dependent manner. Moreover, we found in MCT cells that hypoxia-induced hydrogen peroxide production was decreased by NAC pretreatment. We further analyzed HIF-$1{\alpha}$, PHD2 and VHL expression in the NAC-pretreated MCT cells and assessed the response of antioxidant enzymes at the transcriptional and translational levels. SOD3 and Prdx2 were significantly increased during hypoxia in the mouse kidney. We also confirmed in hypoxic $Prdx2^{-/-}$ and SOD3 transgenic mice that erythropoietin (EPO) is transcriptionally regulated by HIF-$1{\alpha}$. In addition, although EPO protein was found to be expressed in a HIF-$1{\alpha}$ independent manner in three mouse lines, its activity differed markedly between normal and $Prdx2^{-/-}$/SOD3 transgenic mice during hypoxic stress. In conclusion, our current results indicate that NADPH oxidase-mediated ROS generation is associated with hypoxic stress in the mouse kidney and that SOD3 and Prdx2 cooperate to regulate cellular redox reactions during hypoxia.