• Title/Summary/Keyword: Reduced Reaction Mechanism

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Protective effect of Buddha's Temple extract against tert-butyl hydroperoxide stimulation-induced oxidative stress in DF-1 cells

  • Eun Hye Park;Sung-Jo Kim
    • Animal Bioscience
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    • v.36 no.7
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    • pp.1120-1129
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    • 2023
  • Objective: This study aimed to determine the protective efficacy of Buddha's Temple (BT) extract against tert-butyl hydroperoxide (t-BHP)-induced oxidative stress in Gallus gallus chicken embryo fibroblast cell line (DF-1) and its effects on the cell lipid metabolism. Methods: In this experimental study, Gallus gallus DF-1 fibroblast cells were pretreated with BT 10-7 for 24 hours, followed by their six-hour exposure to t-BHP (100 μM). Water-soluble tetrazolium salt-8 (WST-8) assays were performed, and the growth curve was computed. The intracellular gene expression changes caused by BT extract were confirmed through quantitative polymerase chain reaction (qPCR). Flow cytometry, oil red O staining experiment, and thin-layer chromatography were performed for the detection of intracellular metabolic mechanism changes. Results: The WST-8 assay results showed that the BT pretreatment of Gallus gallus DF-1 fibroblast cell increased their cell survival rate by 1.08%±0.04%, decreased the reactive oxygen species (ROS) level by 0.93%±0.12% even after exposure to oxidants, and stabilized mitochondrial activity by 1.37%±0.36%. In addition, qPCR results confirmed that the gene expression levels of tumor necrosis factor α (TNFα), TIR domain-containing adapter inducing IFN-beta (TICAM1), and glucose-regulated protein 78 (GRP78) were regulated, which contributed to cell stabilization. Thin-layer chromatography and oil red O analyses showed a clear decrease in the contents of lipid metabolites such as triacylglycerol and free fatty acids. Conclusion: In this study, we confirmed that the examined BT extract exerted selective protective effects on Gallus gallus DF-1 fibroblast cells against cell damage caused by t-BHP, which is a strong oxidative inducer. Furthermore, we established that this extract significantly reduced the intracellular ROS accumulation due to oxidative stress, which contributes to an increase in poultry production and higher incomes.

Subcutaneous Streptococcus dysgalactiae GAPDH vaccine in mice induces a proficient innate immune response

  • Ran An;Yongli Guo;Mingchun Gao;Junwei Wang
    • Journal of Veterinary Science
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    • v.24 no.5
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    • pp.72.1-72.16
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    • 2023
  • Background: Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) on the surface of Streptococcus dysgalactiae, coded with gapC, is a glycolytic enzyme that was reported to be a moonlighting protein and virulence factor. Objective: This study assessed GAPDH as a potential immunization candidate protein to prevent streptococcus infections. Methods: Mice were vaccinated subcutaneously with recombinant GAPDH and challenged with S. dysgalactiae in vivo. They were then evaluated using histological methods. rGAPDH of mouse bone marrow-derived dendritic cells (BMDCs) was evaluated using immunoblotting, reverse transcription quantitative polymerase chain reaction, and enzyme-linked immunosorbent assay methods. Results: Vaccination with rGAPDH improved the survival rates and decreased the bacterial burdens in the mammary glands compared to the control group. The mechanism by which rGAPDH vaccination protects against S. dysgalactiae was investigated. In vitro experiments showed that rGAPDH boosted the generation of interleukin-10 and tumor necrosis factor-α. Treatment of BMDCs with TAK-242, a toll-like receptor 4 inhibitor, or C29, a toll-like receptor 2 inhibitor, reduced cytokines substantially, suggesting that rGAPDH may be a potential ligand for both TLR2 and TLR4. Subsequent investigations showed that rGAPDH may activate the phosphorylation of MAPKs and nuclear factor-κB. Conclusions: GAPDH is a promising immunization candidate protein for targeting virulence and enhancing immune-mediated protection. Further investigations are warranted to understand the mechanisms underlying the activation of BMDCs by rGAPDH in a TLR2- and TLR4-dependent manner and the regulation of inflammatory cytokines contributing to mastitis pathogenesis.

Protective Effects of Nypa fruticans Wurmb against Oxidative DNA Damage and UVB-induced DNA Damage

  • So-Yeon Han;Tae-Won Jang;Da-Yoon Lee;Seo-Yoon Park;Woo-Jin Oh;Se Chul Hong;Jae-Ho Park
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2023.04a
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    • pp.54-54
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    • 2023
  • Nypa fruticans Wurmb (N. fruticans) is a plant that belongs to Araceae and N. fruticans is mainly found in tropical mangrove systems. The parts (leaves, stems, and roots) of N. fruticans are traditionally used for asthma, sore throat, and liver disease. N. fruticans contains flavonoids and polyphenols, which are substances that have inhibitory effects on cancer and oxidant. In previous studies, some pharmaceutical effects of N. fruticans on melanogenesis and inflammation have been reported. The present study is conducted to investigate the effect of the ethyl acetate fraction of N. fruticans (ENF) on oxidative DNA damage and UVB-induced DNA damage. DNA damage response (DDR) pathway is important in research on cancer, apoptosis, and so on. DDR pathways are considered a crucial factor affecting the alleviation of cellular damage. ENF could reduce oxidative DNA damage derived from reactive oxygen species by the Fenton reaction. Also, ENF reduced the intensity of intracellular ROS in the live cell image by DCFDA assay. UVB is known to cause skin and cellular damage, then finally contribute to causing the formation of tumors. As for the strategies of reducing DNA damage by UVB, inhibition of p53, H2AX, and Chk2 can be important indexes to protect the human body from DNA damage. As a result of confirming the protective effect of ENF for UVB damage, MMPs significantly decreased, and the expression of apoptosis-related factors tended to decrease. In conclusion, ENF can provide protective effects against double-stranded DNA break (DSB) caused by oxidative DNA damage and UVB-induced DNA damage. These results are considered to be closely related to the protective effect against radicals based on catechin, epicatechin, and isoquercitrin contained in ENF. Based on these results, it is thought that additional mechanism studies for inhibiting cell damage are needed.

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Molybdenum-Based Electrocatalysts for Direct Alcohol Fuel Cells: A Critical Review

  • Gaurav Kumar Yogesh;Rungsima Yeetsorn;Waritnan Wanchan;Michael Fowler;Kamlesh Yadav;Pankaj Koinkar
    • Journal of Electrochemical Science and Technology
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    • v.15 no.1
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    • pp.67-95
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    • 2024
  • Direct alcohol fuel cells (DAFCs) have gained much attention as promising energy conversion devices due to their ability to utilize alcohol as a fuel source. In this regard, Molybdenum-based electrocatalysts (Mo-ECs) have emerged as a substitution for expensive Pt and Ru-based co-catalyst electrode materials in DAFCs, owing to their unique electrochemical properties useful for alcohol oxidation. The catalytic activity of Mo-ECs displays an increase in alcohol oxidation current density by several folds to 1000-2000 mA mgPt-1, compared to commercial Pt and PtRu catalysts of 10-100 mA mgPt-1. In addition, the methanol oxidation peak and onset potential have been significantly reduced by 100-200 mV and 0.5-0.6 V, respectively. The performance of Mo-ECs in both acidic and alkaline media has shown the potential to significantly reduce the Pt loading. This review aims to provide a comprehensive overview of the bifunctional mechanism involved in the oxidation of alcohols and factors affecting the electrocatalytic oxidation of alcohol, such as synthesis method, structural properties, and catalytic support materials. Furthermore, the challenges and prospects of Mo-ECs for DAFCs anode materials are discussed. This in-depth review serves as valuable insight toward enhancing the performance and efficiency of DAFC by employing Mo-ECs.

Testicular fat deposition attenuates reproductive performance via decreased follicle-stimulating hormone level and sperm meiosis and testosterone synthesis in mouse

  • Miao Du;Shikun Chen;Yang Chen;Xinxu Yuan;Huansheng Dong
    • Animal Bioscience
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    • v.37 no.1
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    • pp.50-60
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    • 2024
  • Objective: Testicular fat deposition has been reported to affect animal reproduction. However, the underlying mechanism remains poorly understood. The present study explored whether sperm meiosis and testosterone synthesis contribute to mouse testicular fat deposition-induced reproductive performance. Methods: High fat diet (HFD)-induced obesity CD1 mice (DIO) were used as a testicular fat deposition model. The serum hormone test was performed by agent kit. The quality of sperm was assessed using a Sperm Class Analyzer. Testicular tissue morphology was analyzed by histochemical methods. The expression of spermatocyte marker molecules was monitored by an immuno-fluorescence microscope during meiosis. Analysis of the synthesis of testosterone was performed by real-time polymerase chain reaction and reagent kit. Results: It was found that there was a significant increase in body weight among DIO mice, however, the food intake showed no difference compared to control mice fed a normal diet (CTR). The number of offspring in DIO mice decreased, but there was no significant difference from the CTR group. The levels of follicle-stimulating hormone were lower in DIO mice and their luteinizing hormone levels were similar. The results showed a remarkable decrease in sperm density and motility among DIO mice. We also found that fat accumulation affected the meiosis process, mainly reflected in the cross-exchange of homologous chromosomes. In addition, overweight increased fat deposition in the testis and reduced the expression of testosterone synthesis-related enzymes, thereby affecting the synthesis and secretion of testosterone by testicular Leydig cells. Conclusion: Fat accumulation in the testes causes testicular cell dysfunction, which affects testosterone hormone synthesis and ultimately affects sperm formation.

Glucocorticoids improve sperm performance in physiological and pathological conditions: their role in sperm fight/flight response

  • Vittoria Rago;Adele Vivacqua;Saveria Aquila
    • Anatomy and Cell Biology
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    • v.57 no.1
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    • pp.119-128
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    • 2024
  • Glucocorticoids play a physiologic role in the adult male reproductive functions, modulating gonadal steroid synthesis and spermatogenesis, through the glucocorticoid receptor (GR). The expression of GR has been described in several key testicular cell types, including somatic cells and early germ cell populations. Nothing is known on GR in human spermatozoa. Herein, we explored the GR expression and its possible role in normal and testicular varicocele semen samples from volunteer donors. After semen parameter evaluation by macro- and microscopic analysis, samples were centrifuged; then spermatozoa and culture media were recovered for further investigations. By western blotting and immunofluorescence analyses we evidenced for the first time in spermatozoa the presence of GR-D3 isoform which was reduced in sperm from varicocele patients. By treating sperm with the synthetic glucocorticoid dexamethasone (DEXA), we found that survival, motility, capacitation, and acrosome reaction were increased in both healthy and varicocele samples. GR involvement in mediating DEXA effects, was confirmed by using the GR inhibitor mifepristone (M2F). Worthy, we also discovered that sperm secretes different cortisol amounts depending on its physio-pathological status, suggesting a defence mechanism to escape the immune system attach in the female genital tract thus maintaining the immune-privilege as in the testis. Collectively, our data suggests a role for glucocorticoids in determining semen quality and function, as well as in participating on sperm immune defensive mechanisms. The novelty of this study may be beneficial and needs to take into account in artificial insemination/drug discovery aimed to enhancing sperm quality.

Separation Behavior of Vanadium and Tungsten from the Spent SCR DeNOX Catalyst by Strong Basic Anion Exchange Resin (SCR 탈질 폐촉매로부터 강염기성 음이온교환수지를 이용한 바나듐/텅스텐 분리거동 고찰)

  • Heo, Seo-Jin;Jeon, Jong-Hyuk;Kim, Chul-Joo;Chung, Kueong-Woo;Jeon, Ho-Seok;Yoon, Do-Young;Yoon, Ho-Sung
    • Resources Recycling
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    • v.29 no.5
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    • pp.38-47
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    • 2020
  • In this study, factors affecting the adsorption reaction for the separation/recovery of V and W using Lewatit monoplus MP 600, a strong basic anion exchange resin, from the leachate obtained through the soda roasting-water leaching process from the spent SCR DeNOX catalyst investigated and the adsorption mechanism was discussed based on the results. In the case of the mixed solution of V and W, both ions showed a high adsorption ratio at pH 2-6, but the adsorption of W was greatly reduced at pH 8. In the adsorption isothermal experiment, both V and W were fitted well at the Langmuir adsorption isotherm, and the reaction kinetics were fitted well at pseudo-second-order. As a result of conducting an adsorption experiment by adjusting the pH with H2SO4 to remove Si, which inhibits the adsorption of V and W from the leachate, the lowest W adsorption ratio was shown at pH 8.5. Desorption of W was hardly achieved in strongly acidic solutions, and desorption of V was well performed in both strongly acidic and strongly basic solutions.

Effects of all-trans retinoic acid on expression of Toll-like receptor 5 on immune cells (All-trans retinoic acid가 면역세포의 Toll-like receptor 5 발현에 미치는 영향)

  • Kim, Ki-Hyung;Park, Sang-Jun
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.36 no.6
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    • pp.481-489
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    • 2010
  • Introduction: TLR-5, a member of the toll-like receptor (TLR) family, is a element of the type I transmembrane receptors, which are characterized by an intracellular signaling domain homolog to the interleukin-1 receptor. These receptors recognize microbial components, particularly bacterial flagellin. All-trans retinoic acid (atRA, tretinoin), a natural metabolite of vitamin A, acts as a growth and differentiation factor in many tissues, and is also needed for immune functions. In this study, THP-1 human macrophage-monocytes were used to examine the mechanisms by which atRA regulated the expression of TLR-5. Because the molecular mechanism underlying this regulation at the transcriptional level is also unclear, this study examined which putative transcription factors are responsible for TLR-5 expression by atRA in immune cells. Materials and Methods: This study examined whether atRA induces the expression of TLR-5 in THP-1 cells using reverse transcription-polymerase chain reaction (RT-PCR), and which transcription factors are involved in regulating the TLR-5 promoter in RAW264.7 cells using a reporter assay system. Western blot analysis was used to determine which signal pathway is involved in the expression of TLR-5 in atRA-treated THP-1 cells. Results: atRA at a concentration of 10 nM greatly induced the expression of TLR-5 in THP-1 cells. Human TLR-5 promoter contains three Sp-1/GC binding sites around -50 bp and two NF-kB binding sites at -380 bp and -160 bp from the transcriptional start site of the TLR-5 gene. Sp-1/GC is primarily responsible for the constitutive TLR-5 expression, and may also contribute to NF-kB at -160 bp to induce TLR-5 after atRA stimulation in THP-1 cells. The role of NF-kB in TLR-5 expression was further confirmed by inhibitor pyrrolidine dithiocarbamate (PDTC) experiments, which greatly reduced the TLR-5 transcription by 70-80%. Conclusion: atRA induces the expression of the human TLR-5 gene and NF-kB is a critical transcription factor for the atRA-induced expression of TLR-5. Accordingly, it is conceivable that retinoids are required for adequate innate and adaptive immune responses to agents of infectious diseases. atRA and various synthetic retinoids have been used therapeutically in human diseases, such as leukemia and other cancers due to the antiproliferative and apoptosis inducing effects of retinoids. Therefore, understanding the molecular regulatory mechanism of TLR-5 may assist in the design of alternative strategies for the treatment of infectious diseases, leukemia and cancers.

Effects of Ethanol Extract of Liriope platyphylla on Allergic Inflammation (맥문동(麥門冬) 에탄올 추출물이 알레르기 염증 반응에 미치는 영향)

  • Kim, Ho Seok;Park, Ji Hye;Kim, Hyun Kab;Kim, Jae Hyun;Lee, Bina;Min, Ju Hee;Kim, Eun Young;Jung, Hyuk Sang;Lee, Hyang Sook;Sohn, Young Joo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.28 no.5
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    • pp.512-519
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    • 2014
  • This study investegated the effect of Liriope platyphylla (LP) on allergic reactions and its mechanism of action. We investigated the effect of LP on Evans Blue (EB) extravasation induced by anti-dinitrophenyl (DNP)-IgE in rats. We tested whether the ethanol extract of LP reduced ear skin thickness and historical changes induced by topical application of 2,4-dinitrofluorobenzene (DNFB) to ears of mice. We evaluated compound 48/80-induced release of histamine in rats peritoneal mast cell (RPMCs). We also investigated the regulatory effect of LP on the level of inflammatory mediators in PMACI-induced human mast cell (HMC-1); cytokine IL-6, IL-8, TNF-${\alpha}$ in HMC-1, MAPKs (ERK, JNK and p38) in HMC-1. The ethanol extract of LP (81.3 mg/100 g body weight) significantly inhibited the PCA reaction compared with the control (P < 0.05). However, LP did not prevent topical applications of DNFB-induced ear skin thickening and histological changes. In RPMCs, histamine release induced by compound 48/80 was significantly attenuated by LP at $100{\mu}g/ml$ (P < 0.05). LP extract ($100{\mu}g/ml$) significantly reduced the PMACI-induced IL-6, IL-8, and TNF-${\alpha}$ secretion via inhibition of ERK phosphorylation in HMC-1. In conclusion, the ethanol extract of LP inhibited mast cell-derived, immediate-type allergic reactions, and the result suggest the potential of LP for preventing allergic inflammatory disorders.

Association of Schizophrenia with Pathological Aging : A Behavioral and Histological Study Using Animal Model (정신분열병과 병적 노화의 연관성 : 동물모형을 이용한 행동 및 조직학적 연구)

  • Cheon, Jin-Sook;Oh, Byoung-Hoon;Chang, Hwan-Il
    • Korean Journal of Biological Psychiatry
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    • v.5 no.1
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    • pp.83-94
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    • 1998
  • Objectives : Phencyclidine(PCP) or PCP-like substances such as ketamine have been known to rekindle the cognitive dysfunction in schizophrenia. The aims of this study were to identify whether PCP-like substances can produce cognitive deficit in schizophrenia, to discuss relation with aging process, and finally to speculate underlying neurochemical mecha-nisms by various drug responses. Methods : In experiment I, radial maze tests were done in 24 Sprague-Dawley rats for 3 days to get baseline data. Being divided into 4 groups(6 rats respectively) of normal aged, normal adult controls, atropine-treated and ketamine-treated, the radial maze tests were repeated on every week for 6 weeks, and then the rats were sacrificed by intracardiac perfusion with phosphate-buffered 10% formaldehyde solution for histology. The brain specimen was stained with hematoxylin-eosin to count cells in the prefrontal cortex and hippocampus. In experiment II, radial maze tests were done for 48 rats before any drug treatment and only after ketamine administration. Thereafter, haloperidol, bromocriptine, clonidine, nimodipine, tacrine, valproic acid, naloxone and fluoxetine were intramuscularly injected on every other day in addition to ketamine. Radial maze tests were repeated on every week for 6 weeks, and then rats were prepared by the same procedure for histology. Results : 1) Reaction times of radial maze tests of atropine-treated rats were significantly prolonged than those of normal aged(p<0.05) or normal adult controls(p<0.05). Cell numbers of prefrontal cortex & hippocampus in ketamine-treated rats were significantly reduced than those in normal aged (p<0.05) or normal adult controls(p<0.005). 2) Reduced cell numbers by ketamine became significantly raised by tacrine administration in prefrontal cortex & hippocampus(p<0.05), while there were no significant changes on radial maze tests. Cell numbers also tended to be raised by nimodipine, fluoxetine and haloperidol administration. Conclusions : In conclusion, the visuospatial memory disorders in ketamine-induced psychotic rats might be partly asso-ciated with aging process. Furthermore, the responses to the various drugs suggested cholinergic system might have an important role in the neurochemical mechanism of the cognitive dysfunction in ketamine-induced psychosis. Otherwise, calcium metabolism as well as serotonergic and dopaminergic systems seemed to be possibly related.

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