• Title/Summary/Keyword: cellular activities

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Structural Features of Polyphenolic Compounds in Their NO Inhibitory Activities

  • Kim, Byung-Hun;Lee, Yong-Gyu;Kim, Tae-Woong;Cho, Jae-Youl
    • Biomolecules & Therapeutics
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    • v.17 no.1
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    • pp.79-85
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    • 2009
  • Polyphenolic compounds are reported to have various pharmacological activities such as anti-oxidative, anti-cancerous, anti-inflammatory and anti-aging effects. Although numerous papers explore their functional roles in many different cellular actions, not many studies handle their structural features in anti-inflammatory responses. In this study, therefore, we examined structural role of substituted transstilbenes in their NO inhibitory and NF-${\kappa}B$ suppressive activities. Of 10 compounds tested, 4 compounds (cinnamic acid, resveratrol, piceatannol and curcumin) displayed NO inhibitory activities in a dose-dependent manner. Similarly, these compounds blocked LPS-induced cytotoxicity of RAW264.7 cells. All NO inhibitory compounds also inhibited $I{\kappa}B{\alpha}$ phosphorylation, a hallmark for NF-${\kappa}B$ activation. However, these inhibitory compounds exhibited distinct suppressive pattern in tumor necrosis factor (TNF)-${\alpha}$- or phorbol-12-myristate-13-acetate (PMA)-induced NF-${\kappa}B$ and AP-1 activation. According to structure-activity relationship study, polarity and size of ring B seem to be important for diminishing NO production. Therefore, our data suggest that substituted trans-stilbenes can be developed as novel anti-inflammatory drug or further developed as lead compounds for another improvement.

Signal Transduction of the Cytokine Receptor

  • Watanabe, Sumiko
    • Animal cells and systems
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    • v.2 no.2
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    • pp.153-164
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    • 1998
  • Cytokines regulate proliferation, differentiation and functions of haemotopoietic cells. Each cytokine possesses a variety of activities on various target cells (pleiotropy) and various cytokines have similar and overlapping activities on the same target cells (redundancy). The nature of these cytokine activities predicts unique feature of cytokine receptors, namely, cytokine has multiple receptors, different cytokines share a common receptor, and different cytokine receptors are linked to common signaling pathways. cDNA cloning of genes for cytokine receptors revealed distinct sets of receptor family with different structural features. The cytokine receptor superfamily consists of a largest family, and contains more than twenty cytokine receptor subunits. This receptor has common structural features in both extracellular and intracellular regions without tyrosine kinase domain. Another striking feature of the receptor is to share common subunit of multiple cytokines, which partly explains the redundancy of activities of some cytokines. Recent studies revealed detailed signaling events of the cytokine receptor, the primary activation of JAK and subsequent phosphorylation of tyrosine residues of receptor, and various cellular proteins. Many SH2 containing adapter proteins play an important role in cytokine signals, and this system has similarities with tyrosine kinase receptor signal transduction. STAT may mainly account for cytokine specific functions as suggested by knockout mice studies. It is of importance to note that cytokine activates multiple signaling pathways and the balance and combination of related signaling events may determine the specificity of functions of cytokines.

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A Study on the Tyrosinase Inhibitory and Antioxidant Effect of Microalgae Extracts

  • Ji, Keunho;Kim, Yeeun;Kim, Young Tae
    • Microbiology and Biotechnology Letters
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    • v.49 no.2
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    • pp.167-173
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    • 2021
  • Reactive oxygen species (ROS) disrupt the cellular redox balance, exert cytotoxic effects, and consequently promote the development of various diseases in humans. Previous studies have reported that antioxidants counteract the adverse effects of ROS. Several studies examine the whitening effects of various agents based on their ability to inhibit tyrosinase activity. Tyrosinase is a critical enzyme involved in the synthesis of melanin, which protects the skin against radiation. Various agents exhibiting antioxidant and tyrosinase inhibitory activities have been synthesized. However, these synthetic drugs are associated with toxicity, decreased safety, and poor skin penetration in vivo, which has limited the clinical application of synthetic drugs. This study examined the antioxidant and tyrosinase inhibitory activities of some microalgae. The methanol, dichloromethane, and ethyl acetate extracts of four microalgal species (Tetraselmis tetrathele, Dunaliella tertiolecta, Platymonas sp., and Chaetoceros simplex) were prepared. The physiological and whitening effects of microalgal extracts were investigated by measuring the antioxidant and tyrosinase inhibitory activities. The ethyl acetate extract of D. tertiolecta exhibited the highest antioxidant and tyrosinase inhibitory activities. Future studies must focus on examining the whitening effects of microalgae on cell lines to facilitate the development of microalga-based therapeutics for skin diseases, functional health foods, and whitening agents. Thus, microalgae have potential applications in the pharmaceutical, food, and cosmetic industries.

Whitening and Anti-oxidative Activities of Chemical Components Extracted from Branches of Sorbus alnifolia

  • Bo Shi Liu;Jung Eun Kim;Nam Ho Lee
    • Journal of the Korean Chemical Society
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    • v.67 no.2
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    • pp.137-144
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    • 2023
  • In this study were evaluated the whitening and anti-oxidative activities from the extracts of Sorbus alnifolia branches, and identified the chemical structures of the active ingredients. In the whitening tests using α-MSH stimulated B16F10 melanoma cells, the 70% ethanol extract and n-butanol (n-BuOH) fractions concentration-dependently inhibited cellular melanogenesis and intracellular tyrosinase activities without causing cell toxicity. The total polyphenol content of n-BuOH and ethyl acetate (EtOAc) fractions were measured to be respectively 241.1 ± 1.1 and 222.9 ± 2.4 (mg/g GAE), and the total flavonoid content of EtOAc fraction was 75.3 ± 2.0 (mg/g QE). Upon anti-oxidant studies with DPPH and ABTS+ radicals, potent radical scavenging activities were observed in the EtOAc and n-BuOH fractions. Moreover, in the study of cell protection efficacy using HaCaT keratinocytes damaged by H2O2, the EtOAc and n-BuOH fractions showed a very positive results on prevention of oxidative stress. Phytochemical studies for this extract resulted in the isolation of four compounds; 2-oxopomolic acid (1), euscaphic acid (2), epi-catechin (3), prunasin (4). These results suggested that the extract of S. alnifolia branches containing compounds 1-4 as natural ingredients could be used as whitening and anti-oxidant ingredients in cosmetic formulations.

The beneficial effect of ginsenosides extracted by pulsed electric field against hydrogen peroxide-induced oxidative stress in HEK-293 cells

  • Liu, Di;Zhang, Ting;Chen, Zhifei;Wang, Ying;Ma, Shuang;Liu, Jiyun;Liu, Jingbo
    • Journal of Ginseng Research
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    • v.41 no.2
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    • pp.169-179
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    • 2017
  • Background: Ginsenosides are the main pharmacological components of Panax ginseng root, which are thought to be primarily responsible for the suppressing effect on oxidative stress. Methods: 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and oxygen radical absorption capacity were applied to evaluate the antioxidant activities of the ginsenosides. Human embryonic kidney 293 (HEK-293) cells were incubated with ginsenosides extracted by pulsed electric field (PEF) and solvent cold soak extraction (SCSE) for 24 h and then the injury was induced by $40{\mu}M$ $H_2O_2$. The cell viability and surface morphology of HEK-293 cells were studied using MTS assay and scanning electron microscopy, respectively. Dichloro-dihydro-fluorescein diacetate fluorescent probe assay was used to measure the level of intracellular reactive oxygen species. The intracellular antioxidant activities of ginsenosides were evaluated by cellular antioxidant activity assay in HepG2 cells. Results: The PEF extracts displayed the higher 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and stronger oxygen radical absorption capacity (with an oxygen radical absorption capacity value of $14.48{\pm}4.04{\mu}M\;TE\;per\;{\mu}g/mL$). The HEK-293 cell model also suggested that the protective effect of PEF extracts was dose-dependently greater than SCSE extracts. Dichloro-dihydro-fluorescein diacetate assay further proved that PEF extracts are more active (8% higher than SCSE extracts) in reducing intracellular reactive oxygen species accumulation. In addition, scanning electron microscopy images showed that the HEK-293 cells, which were treated with PEF extracts, maintained more intact surface morphology. Cellular antioxidant activity values indicated that ginsenosides extracted by PEF had stronger cellular antioxidant activity than SCSE ginsenosides extracts. Conclusion: The present study demonstrated the antioxidative effect of ginsenosides extracted by PEF in vitro. Furthermore, rather than SCSE, PEF may be more useful as an alternative extraction technique for the extraction of ginsenosides with enhanced antioxidant activity.

Effects of Heated Oil and Vitamin E on Lipid Peroxidative Liver Damage in Rat (가열유와 Vitamin E가 흰쥐 간장내의 과산화적 손상에 미치는 영향)

  • 이순재;최원경
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.20 no.2
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    • pp.111-120
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    • 1991
  • In order to investigate the cellular peroxidative damage due to heated oil intake and the preventive effect of vitamin E on it rats were fed heated corn oil with acid value of 4.02 at the level of 10 Cal% and three different levels of vitamin E that were 0, 40 and 200 mg/kg diet. Control group was fed fresh corn oil and 40mg/kg diet of vitamin E. After ech feeding period of 0, 3 and 6 weeks, liver superoxide dismutase (SOD), glutathione peroxidase (GPX) activities and microsomal content of vitamin E and lipid peroxide (LPO) were measured as well as cellular morphology was examined. SOD activities and LPO contents were higher, while GPX activities and vitamin e contents were lower in heated oil groups than control group. Electromicroscopic observation revealed the loss of inner mitochondrial membrane and cristae and irregular arrangement of nuclear membrane and chromatin in heated oil groups. As dietary vitamin e level was increased, SOD activity and LPO content were decreased, but GPX activity and vitamin E content in the liver increased and cellular peroxidative damage reduced progressively. This phenomena was more remarkable in 6 weeks of feeding than 3 weeks.

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Continuous DC-CIK Infusions Restore CD8+ Cellular Immunity, Physical Activity and Improve Clinical Efficacy in Advanced Cancer Patients Unresponsive to Conventional Treatments

  • Zhao, Yan-Jie;Jiang, Ni;Song, Qing-Kun;Wu, Jiang-Ping;Song, Yu-Guang;Zhang, Hong-Mei;Chen, Feng;Zhou, Lei;Wang, Xiao-Li;Zhou, Xin-Na;Yang, Hua-Bing;Ren, Jun;Lyerly, Herbert Kim
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.6
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    • pp.2419-2423
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    • 2015
  • Background: There are few choices for treatment of advanced cancer patients who do not respond to or tolerate conventional anti-cancer treatments. Therefore this study aimed to deploy the benefits and clinical efficacy of continuous dendritic cell-cytokine induced killer cell infusions in such patients. Materials and Methods: A total of 381 infusions (from 67 advanced cases recruited) were included in this study. All patients underwent peripheral blood mononuclear cell apheresis for the following cellular therapy and dendritic cells-cytokine induced killer cells were expanded in vitro. Peripheral blood T lymphocyte subsets were quantified through flow cytometry to address the cellular immunity status. Clinical efficacy and physical activities were evaluated by RECIST criteria and Eastern Cooperative Oncology Group scores respectively. Logistic regression model was used to estimate the association between cellular infusions and clinical benefits. Results: An average of $5.7{\pm}2.94{\times}10^9$ induced cells were infused each time and patients were exposed to 6 infusions. Cellular immunity was improved in that cytotoxic $CD8^+CD28^+$ T lymphocytes were increased by 74% and suppressive $CD8^+CD28^-$ T lymphocytes were elevated by 16% (p<0.05). Continuous infusion of dendritic cells-cytokine induced killer cells was associated with improvement of both patient status and cellular immunity. A median of six infusions were capable of reducing risk of progression by 70% (95%CI 0.10-0.91). Every elevation of one ECOG score corresponded to a 3.90-fold higher progression risk (p<0.05) and 1% increase of $CD8^+CD28^-$ T cell proportion reflecting a 5% higher risk of progression (p<0.05). Conclusions: In advanced cancer patients, continuous dendritic cell-cytokine induced killer cell infusions are capable of recovering cellular immunity, improving patient status and quality of life in those who are unresponsive to conventional cancer treatment.

Effect of Multiple Copies of Cohesins on Cellulase and Hemicellulase Activities of Clostridium cellulovorans Mini-cellulosomes

  • Cha, Jae-Ho;Matsuoka, Satoshi;Chan, Helen;Yukawa, Hideaki;Inui, Masayuki;Doi, Roy H.
    • Journal of Microbiology and Biotechnology
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    • v.17 no.11
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    • pp.1782-1788
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    • 2007
  • Cellulosomes in Clostridium cellulovorans are assembled by the interaction between the repeated cohesin domains of a scaffolding protein (CbpA) and the dockerin domain of enzyme components. In this study, we determined the synergistic effects on cellulosic and hemicellulosic substrates by three different recombinant mini-cellulosomes containing either endoglucanase EngB or endoxylanase XynA bound to mini-CbpA with one cohesin domain (mini-CbpAl), two cohesins (mini-CbpA12), or four cohesins (mini-CbpAl234). The assembly of EngB or XynA with mini-CbpA increased the activity against carboxymethyl cellulose, acid-swollen cellulose, Avicel, xylan, and com fiber 1.1-1.8-fold compared with that for the corresponding enzyme alone. A most distinct improvement was shown with com fiber, a natural substrate containing xylan, arabinan, and cellulose. However, there was little difference in activity between the three different mini-cellulosomes when the cellulosomal enzyme concentration was held constant regardless of the copy number of cohesins in the cellulosome. A synergistic effect was observed when the enzyme concentration was increased to be proportional to the number of cohesins in the mini-cellulosome. The highest degree of synergy was observed with mini-CbpAl234 (1.8-fold) and then mini-CbpAl2 (1.3-fold), and the lowest synergy was observed with mini-CbpAl (1.2-fold) when Avicel was used as the substrate. As the copy number of cohesin was increased, there was more synergy. These results indicate that the clustering effect (physical enzyme proximity) of the enzyme within the mini-cellulosome is one of the important factors for efficient degradation of plant cell walls.

AN IMMUNOHISTOCHEMICAL STUDY ON PROLIFERATION, DIFFERENTIATION, AND APOPTOSIS IN THE EPITHELIAL CELLS OF THE ODONTOGENIC CYSTS (치성낭종 상피세포의 증식, 분화 및 세포능동사망현상에 관한 면역조직화학적 연구)

  • Chung, Seong-Hoon;Park, Young-Wook;Joo, Jae-Yong;Lee, Suk-Keun
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.26 no.5
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    • pp.470-480
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    • 2000
  • The epithelium of odontogenic cyst seems to be in a specific status of cellular proliferation and cytodifferentiation. With the identification of various genes, which play essential roles in the specific stages of cellular proliferation and differentiation, the cellular conditions of odontogenic cyst epithelium need to be reevaluated. This study aimed to estimate the degree of proliferating, differentiating and apoptotic activities of odontogenic cyst epithelium using antisera of PCNA, Ki-67, MPM-2, transglutaminase C, heat shock protein 70 and $ApopTag$^{(R)}$. method in 19 cases of odontogenic cysts. Cellular changes of the cyst epithelium were measured by intensity of each immunohistochemical staining. Results were as follows: 1. The proliferating activity of the cyst epithelium was slightly lower than that of normal oral mucosal epithelium, with the use of primary antibodies against PCNA, Ki-67, and MPM-2. And the proliferating activity of the epithelium in OKC group was even higher than that of the epithelium in non-OKC group. 2. The odontogenic cysts showed weakly positive reaction with transglutaminase C, but strongly positive reaction with HSP 70. 3. Occasionally, only a few apoptotic cell was observed in the superficial keratin layer of OKC. 4. The hyperplastic cyst epithelium infiltrated with mild inflammatory cells showed diffusely positive reaction with different proliferating factors. From the above results, we presumed that the endogenous proliferating and differentiating activity of the cyst epithelium was slightly lower than that of normal oral mucosal epithelium, and also supposed that the cyst epithelium could be reactivated for the further proliferation by the exogenous factors, such as inflammatory reaction and any chemicophysical irritations.

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THE EFFECTS OF NICOTINE ON HUMAN GINGIVAL FIBROBLAST & PERIODONTAL LIGAMENT CELLS IN VITRO (니코틴이 배양인체 치은섬유모세포 및 치주인대세포의 활성에 미치는 효과)

  • Kong, Young-Hwan;Yoo, Hyung-Keun;Shin, Hyung-Shik
    • Journal of Periodontal and Implant Science
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    • v.25 no.2
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    • pp.181-191
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    • 1995
  • The ability of fibroblasts attach to teeth is of paramount imporance in re-establishing the lost connective tissue attachment after periodontal therapy. Tobacco contains a complex mixture of substances including nicotine. various nitrousamines, trace elements. and a variety of poorly characterized substances. The effects of nicotine on fibroblasts have reported an altered morphology and attachment of fibroblasts to substrates and disturbances in protein synthesis and secretion. This study examined the effect of nicotine, a major component of the particulate phase of tobacco smoke, on human gingival fibroblasts and periodontal ligament cells attachment to tissue culture surfaces and cellular activity of human gingival fibroblasts and periodontal ligament cells. Pooled human gingival fibroblasts made from extraction of 3rd molar were utilized between passage 4 and 5 and plated in 96 well plate at 20,000 cells per well. Cell number were determined using 3-(4,5-dimethylthiazole-2-y)2,5-diphenyltetrazolium bromide(MTI) , which is reflection of mitochondrial dehydrogenase activity. The concentration of nicotine used were 0.025, 0.05, 0.1, 0.2 and $0.4{\mu}M$, the average serum concentration for a smoker being approximately $0.1{\mu}M$. The results were as follows : 1. Attachment effects of nicotine on human gingival fibroblasts and periodontal ligament cells Excepts of $0.4{\mu}M$, the effects on attachment with increasing numbers of cells attaching with increasing nicotine concentrations, compared to control group. But over the 60min, return to control value. 2. The effect of cellular activity on human gingival fibroblasts and periodontal ligament cells. The cellular activity of human gingival fibroblasts and periodontal ligament cells were similar or decrease to control value at 1st incubation day. At 2nd incubation day, 0.05, 0.1, 0.2, $0.4{\mu}M$ concentrations were statistically different from control value on gingival fibroblasts group. But at 3rd incubation day, cellular activities of all experimental group were significantly decrease than control group.

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