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Sample records for cordycepin inhibits uvb-induced

  1. Topical application of Nexrutine inhibits UVB-induced cutaneous inflammatory responses in SKH-1 hairless mouse.

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    Alam, Shamshad; Pal, Anu; Singh, Dhirendra; Ansari, Kausar Mahmood

    2017-08-30

    Ultraviolet B (UVB) radiation is the major contributor to skin inflammation which leads to the development of skin cancer. Hence, in this study, we studied the effect of Nexrutine (NX) on UVB-induced cutaneous inflammation and its mediators. UV absorption spectra of NX were measured by spectrophotometer. To conduct the photoprotective studies, SKH-1 hairless mice were topically treated with NX, 30 minutes before to the UVB (180 mJ/cm(2) ) exposure. Twenty hours of post UVB irradiation, mouse skin was used for edema measurements, H & E staining, myeloperoxidase (MPO) activity and estimation of plasma cytokines. In addition, expression levels of inflammatory cytokines, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) were also determined by western blot analysis. NX displayed absorbance over the UVB spectrum. NX significantly decreased the UVB-induced epidermal edema, skin thickness, leukocyte infiltration, number of the sunburn and TUNEL positive cells. NX treatment also decreased the number of mast cells, MPO activity, expression of pro-inflammatory cytokines and inflammation mediator protein in mouse skin. These results provide evidences that NX inhibits the UVB-induced cutaneous inflammatory responses in SKH-1 mouse skin. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  2. Cyanidin-3-glucoside inhibits UVB-induced oxidative damage and inflammation by regulating MAP kinase and NF-κB signaling pathways in SKH-1 hairless mice skin

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    Pratheeshkumar, Poyil; Son, Young-Ok; Wang, Xin; Divya, Sasidharan Padmaja [Center for Research on Environmental Disease, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Joseph, Binoy [Spinal Cord and Brain Injury Research Center and Department of Physiology, University of Kentucky, Lexington, KY 40536-0509 (United States); Hitron, John Andrew; Wang, Lei [Center for Research on Environmental Disease, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Kim, Donghern [Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Yin, Yuanqin [Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Cancer Institute, The First Affiliated Hospital, China Medical University, Shenyang (China); Roy, Ram Vinod [Center for Research on Environmental Disease, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Lu, Jian [Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013 (China); Zhang, Zhuo [Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Wang, Yitao [State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau (China); and others

    2014-10-01

    Skin cancer is one of the most commonly diagnosed cancers in the United States. Exposure to ultraviolet-B (UVB) radiation induces inflammation and photocarcinogenesis in mammalian skin. Cyanidin-3-glucoside (C3G), a member of the anthocyanin family, is present in various vegetables and fruits especially in edible berries, and displays potent antioxidant and anticarcinogenic properties. In this study, we have assessed the in vivo effects of C3G on UVB irradiation induced chronic inflammatory responses in SKH-1 hairless mice, a well-established model for UVB-induced skin carcinogenesis. Here, we show that C3G inhibited UVB-induced skin damage and inflammation in SKH-1 hairless mice. Our results indicate that C3G inhibited glutathione depletion, lipid peroxidation and myeloperoxidation in mouse skin by chronic UVB exposure. C3G significantly decreased the production of UVB-induced pro-inflammatory cytokines, such as IL-6 and TNF-α, associated with cutaneous inflammation. Likewise, UVB-induced inflammatory responses were diminished by C3G as observed by a remarkable reduction in the levels of phosphorylated MAP kinases, Erk1/2, p38, JNK1/2 and MKK4. Furthermore, C3G also decreased UVB-induced cyclooxygenase-2 (COX-2), PGE{sub 2} and iNOS levels, which are well-known key mediators of inflammation and cancer. Treatment with C3G inhibited UVB-induced nuclear translocation of NF-κB and degradation of IκBα in mice skin. Immunofluorescence assay revealed that topical application of C3G inhibited the expression of 8-hydroxy-2′-deoxyguanosine, proliferating cell nuclear antigen, and cyclin D1 in chronic UVB exposed mouse skin. Collectively, these data indicates that C3G can provide substantial protection against the adverse effects of UVB radiation by modulating UVB-induced MAP kinase and NF-κB signaling pathways. - Highlights: • C3G inhibited UVB-induced oxidative damage and inflammation. • C3G inhibited UVB-induced COX-2, iNOS and PGE{sub 2} production. • C3G

  3. Pyrrolidine dithiocarbamate inhibits UVB-induced skin inflammation and oxidative stress in hairless mice and exhibits antioxidant activity in vitro.

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    Ivan, Ana L M; Campanini, Marcela Z; Martinez, Renata M; Ferreira, Vitor S; Steffen, Vinicius S; Vicentini, Fabiana T M C; Vilela, Fernanda M P; Martins, Frederico S; Zarpelon, Ana C; Cunha, Thiago M; Fonseca, Maria J V; Baracat, Marcela M; Georgetti, Sandra R; Verri, Waldiceu A; Casagrande, Rúbia

    2014-09-05

    Ultraviolet B (UVB) irradiation may cause oxidative stress- and inflammation-dependent skin cancer and premature aging. Pyrrolidine dithiocarbamate (PDTC) is an antioxidant and inhibits nuclear factor-κB (NF-κB) activation. In the present study, the mechanisms of PDTC were investigated in cell free oxidant/antioxidant assays, in vivo UVB irradiation in hairless mice and UVB-induced NFκB activation in keratinocytes. PDTC presented the ability to scavenge 2,2'-azinobis-(3-ethyl benzothiazoline-6-sulfonic acid) radical (ABTS), 2,2-diphenyl-1-picryl-hydrazyl radical (DPPH) and hydroxyl radical (OH); and also efficiently inhibited iron-dependent and -independent lipid peroxidation as well as chelated iron. In vivo, PDTC treatment significantly decreased UVB-induced skin edema, myeloperoxidase (MPO) activity, production of the proinflammatory cytokine interleukin-1β (IL-1β), matrix metalloproteinase-9 (MMP-9), increase of reduced glutathione (GSH) levels and antioxidant capacity of the skin tested by the ferric reducing antioxidant power (FRAP) and ABTS assays. PDTC also reduced UVB-induced IκB degradation in keratinocytes. These results demonstrate that PDTC presents antioxidant and anti-inflammatory effects in vitro, which line up well with the PDTC inhibition of UVB irradiation-induced skin inflammation and oxidative stress in mice. These data suggest that treatment with PDTC may be a promising approach to reduce UVB irradiation-induced skin damages and merits further pre-clinical and clinical studies.

  4. Cordycepin inhibits LPS-induced inflammatory and matrix degradation in the intervertebral disc

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    Yan Li

    2016-05-01

    Full Text Available Cordycepin is a component of the extract obtained from Cordyceps militaris and has many biological activities, including anti-cancer, anti-metastatic and anti-inflammatory effects. Intervertebral disc degeneration (IDD is a degenerative disease that is closely related to the inflammation of nucleus pulposus (NP cells. The effect of cordycepin on NP cells in relation to inflammation and degeneration has not yet been studied. In our study, we used a rat NP cell culture and an intervertebral disc (IVD organ culture model to examine the inhibitory effects of cordycepin on lipopolysaccharide (LPS-induced gene expression and the production of matrix degradation enzymes (MMP-3, MMP-13, ADAMTS-4, and ADAMTS-5 and oxidative stress-associated factors (nitric oxide and PGE2. We found a protective effect of cordycepin on NP cells and IVDs against LPS-induced matrix degradation and macrophage infiltration. In addition, western blot and luciferase assay results demonstrated that pretreatment with cordycepin significantly suppressed the LPS-induced activation of the NF-κB pathway. Taken together, the results of our research suggest that cordycepin could exert anti-inflammatory and anti-degenerative effects on NP cells and IVDs by inhibiting the activation of the NF-κB pathway. Therefore, cordycepin may be a potential treatment for IDD in the future.

  5. Cordycepin Induces Apoptosis and Inhibits Proliferation of Human Lung Cancer Cell Line H1975 via Inhibiting the Phosphorylation of EGFR.

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    Wang, Zheng; Wu, Xue; Liang, Yan-Ni; Wang, Li; Song, Zhong-Xing; Liu, Jian-Li; Tang, Zhi-Shu

    2016-09-27

    Cordycepin is an active component of the traditional Chinese medicine Cordyceps sinensis and Cordyceps militaris with notable anticancer activity. Though the prominent inhibitory activity was reported in different kinds of cancer cell lines, the concrete mechanisms remain elusive. It was reported that cordycepin could be converted into tri-phosphates in vivo to confuse a number of enzymes and interfere the normal cell function. For the inhibitory mechanism of EGFR inhibitors and the structure similarity of ATP and tri-phosphated cordycepin, human lung cancer cell line H1975 was employed to investigate the inhibitory effect of cordycepin. The results showed that cordycepin could inhibit cell proliferation and induce apoptosis in a dose-dependent manner. Cell cycle analysis revealed that H1975 cells could be arrested at the G₀/G₁ phase after cordycepin treatment. The expression levels of apoptosis-related protein Caspase-3 and Bcl-2 and phosphorylated expression levels of EGFR, AKT and ERK1/2 were all decreased compared with the control group stimulated with EGF. However, the protein expression levels of proapoptotic protein Bax and cleaved caspase-3 were increased. These results implied that cordycepin could inhibit cell proliferation and induce apoptosis via the EGFR signaling pathway. Our results indicated that there was potential to seek a novel EGFR inhibitor from cordycepin and its chemical derivatives.

  6. Cordycepin Induces Apoptosis and Inhibits Proliferation of Human Lung Cancer Cell Line H1975 via Inhibiting the Phosphorylation of EGFR

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    Zheng Wang

    2016-09-01

    Full Text Available Cordycepin is an active component of the traditional Chinese medicine Cordyceps sinensis and Cordyceps militaris with notable anticancer activity. Though the prominent inhibitory activity was reported in different kinds of cancer cell lines, the concrete mechanisms remain elusive. It was reported that cordycepin could be converted into tri-phosphates in vivo to confuse a number of enzymes and interfere the normal cell function. For the inhibitory mechanism of EGFR inhibitors and the structure similarity of ATP and tri-phosphated cordycepin, human lung cancer cell line H1975 was employed to investigate the inhibitory effect of cordycepin. The results showed that cordycepin could inhibit cell proliferation and induce apoptosis in a dose-dependent manner. Cell cycle analysis revealed that H1975 cells could be arrested at the G0/G1 phase after cordycepin treatment. The expression levels of apoptosis-related protein Caspase-3 and Bcl-2 and phosphorylated expression levels of EGFR, AKT and ERK1/2 were all decreased compared with the control group stimulated with EGF. However, the protein expression levels of proapoptotic protein Bax and cleaved caspase-3 were increased. These results implied that cordycepin could inhibit cell proliferation and induce apoptosis via the EGFR signaling pathway. Our results indicated that there was potential to seek a novel EGFR inhibitor from cordycepin and its chemical derivatives.

  7. Blackberry extract inhibits UVB-induced oxidative damage and inflammation through MAP kinases and NF-κB signaling pathways in SKH-1 mice skin

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    Divya, Sasidharan Padmaja; Wang, Xin; Pratheeshkumar, Poyil; Son, Young-Ok; Roy, Ram Vinod [Center for Research on Environmental Disease, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Department of Toxicology and Cancer Biology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Kim, Donghern; Dai, Jin [Department of Toxicology and Cancer Biology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Hitron, John Andrew; Wang, Lei [Center for Research on Environmental Disease, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Department of Toxicology and Cancer Biology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Asha, Padmaja [National Centre for Aquatic Animal Health, Cochin University of Science and Technology, Cochin (India); Shi, Xianglin [Center for Research on Environmental Disease, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Department of Toxicology and Cancer Biology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Zhang, Zhuo, E-mail: zhuo.zhang@uky.edu [Department of Toxicology and Cancer Biology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States)

    2015-04-01

    Extensive exposure of solar ultraviolet-B (UVB) radiation to skin induces oxidative stress and inflammation that play a crucial role in the induction of skin cancer. Photochemoprevention with natural products represents a simple but very effective strategy for the management of cutaneous neoplasia. In this study, we investigated whether blackberry extract (BBE) reduces chronic inflammatory responses induced by UVB irradiation in SKH-1 hairless mice skin. Mice were exposed to UVB radiation (100 mJ/cm{sup 2}) on alternate days for 10 weeks, and BBE (10% and 20%) was applied topically a day before UVB exposure. Our results show that BBE suppressed UVB-induced hyperplasia and reduced infiltration of inflammatory cells in the SKH-1 hairless mice skin. BBE treatment reduced glutathione (GSH) depletion, lipid peroxidation (LPO), and myeloperoxidase (MPO) in mouse skin by chronic UVB exposure. BBE significantly decreased the level of pro-inflammatory cytokines IL-6 and TNF-α in UVB-exposed skin. Likewise, UVB-induced inflammatory responses were diminished by BBE as observed by a remarkable reduction in the levels of phosphorylated MAP Kinases, Erk1/2, p38, JNK1/2 and MKK4. Furthermore, BBE also reduced inflammatory mediators such as cyclooxygenase-2 (COX-2), prostaglandin E{sub 2} (PGE{sub 2}), and inducible nitric oxide synthase (iNOS) levels in UVB-exposed skin. Treatment with BBE inhibited UVB-induced nuclear translocation of NF-κB and degradation of IκBα in mouse skin. Immunohistochemistry analysis revealed that topical application of BBE inhibited the expression of 8-oxo-7, 8-dihydro-2′-deoxyguanosine (8-oxodG), cyclobutane pyrimidine dimers (CPD), proliferating cell nuclear antigen (PCNA), and cyclin D1 in UVB-exposed skin. Collectively, these data indicate that BBE protects from UVB-induced oxidative damage and inflammation by modulating MAP kinase and NF-κB signaling pathways. - Highlights: • Blackberry extract inhibits UVB-induced glutathione depletion.

  8. UVB-induced cell death signaling is associated with G1-S progression and transcription inhibition in primary human fibroblasts.

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    Tatiana Grohmann Ortolan

    Full Text Available DNA damage induced by ultraviolet (UV radiation can be removed by nucleotide excision repair through two sub-pathways, one general (GGR and the other specific for transcribed DNA (TCR, and the processing of unrepaired lesions trigger signals that may lead to cell death. These signals involve the tumor suppressor p53 protein, a central regulator of cell responses to DNA damage, and the E3 ubiquitin ligase Mdm2, that forms a feedback regulatory loop with p53. The involvement of cell cycle and transcription on the signaling to apoptosis was investigated in UVB-irradiated synchronized, DNA repair proficient, CS-B (TCR-deficient and XP-C (GGR-deficient primary human fibroblasts. Cells were irradiated in the G1 phase of the cell cycle, with two doses with equivalent levels of apoptosis (low and high, defined for each cell line. In the three cell lines, the low doses of UVB caused only a transient delay in progression to the S phase, whereas the high doses induced permanent cell cycle arrest. However, while accumulation of Mdm2 correlated well with the recovery from transcription inhibition at the low doses for normal and CS-B fibroblasts, for XP-C cells this protein was shown to be accumulated even at UVB doses that induced high levels of apoptosis. Thus, UVB-induced accumulation of Mdm2 is critical for counteracting p53 activation and apoptosis avoidance, but its effect is limited due to transcription inhibition. However, in the case of XP-C cells, an excess of unrepaired DNA damage would be sufficient to block S phase progression, which would signal to apoptosis, independent of Mdm2 accumulation. The data clearly discriminate DNA damage signals that lead to cell death, depending on the presence of UVB-induced DNA damage in replicating or transcribing regions.

  9. Brown Pine Leaf Extract and Its Active Component Trans-Communic Acid Inhibit UVB-Induced MMP-1 Expression by Targeting PI3K.

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    Won Bum Huh

    Full Text Available Japanese red pine (Pinus densiflora is widely present in China, Japan, and Korea. Its green pine leaves have traditionally been used as a food as well as a coloring agent. After being shed, pine leaves change their color from green to brown within two years, and although the brown pine leaves are abundantly available, their value has not been closely assessed. In this study, we investigated the potential anti-photoaging properties of brown pine leaves for skin. Brown pine leaf extract (BPLE inhibited UVB-induced matrix metalloproteinase-1 (MMP-1 expression to a greater extent than pine leaf extract (PLE in human keratinocytes and a human skin equivalent model. HPLC analysis revealed that the quantity of trans-communic acid (TCA and dehydroabietic acid (DAA significantly increases when the pine leaf color changes from green to brown. BPLE and TCA elicited reductions in UVB-induced MMP-1 mRNA expression and activator protein-1 (AP-1 transactivation by reducing DNA binding activity of phospho-c-Jun, c-fos and Fra-1. BPLE and TCA also inhibited UVB-induced Akt phosphorylation, but not mitogen activated protein kinase (MAPK, known regulators of AP-1 transactivation. We additionally found that BPLE and TCA inhibited phosphoinositide 3-kinase (PI3K, the upstream kinase of Akt, in vitro. In summary, both BPLE and its active component TCA exhibit protective effects against UVB-induced skin aging. Taken together, these findings underline the potential for BPLE and TCA to be utilized as anti-wrinkling agents and cosmetic ingredients, as they suppress UVB-induced MMP-1 expression.

  10. Brown Pine Leaf Extract and Its Active Component Trans-Communic Acid Inhibit UVB-Induced MMP-1 Expression by Targeting PI3K.

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    Huh, Won Bum; Kim, Jong-Eun; Kang, Young-Gyu; Park, Gaeun; Lim, Tae-gyu; Kwon, Jung Yeon; Song, Da Som; Jeong, Eun Hee; Lee, Charles C; Son, Joe Eun; Seo, Sang Gwon; Lee, Eunjung; Kim, Jong Rhan; Lee, Chang Yong; Park, Jun Seong; Lee, Ki Won

    2015-01-01

    Japanese red pine (Pinus densiflora) is widely present in China, Japan, and Korea. Its green pine leaves have traditionally been used as a food as well as a coloring agent. After being shed, pine leaves change their color from green to brown within two years, and although the brown pine leaves are abundantly available, their value has not been closely assessed. In this study, we investigated the potential anti-photoaging properties of brown pine leaves for skin. Brown pine leaf extract (BPLE) inhibited UVB-induced matrix metalloproteinase-1 (MMP-1) expression to a greater extent than pine leaf extract (PLE) in human keratinocytes and a human skin equivalent model. HPLC analysis revealed that the quantity of trans-communic acid (TCA) and dehydroabietic acid (DAA) significantly increases when the pine leaf color changes from green to brown. BPLE and TCA elicited reductions in UVB-induced MMP-1 mRNA expression and activator protein-1 (AP-1) transactivation by reducing DNA binding activity of phospho-c-Jun, c-fos and Fra-1. BPLE and TCA also inhibited UVB-induced Akt phosphorylation, but not mitogen activated protein kinase (MAPK), known regulators of AP-1 transactivation. We additionally found that BPLE and TCA inhibited phosphoinositide 3-kinase (PI3K), the upstream kinase of Akt, in vitro. In summary, both BPLE and its active component TCA exhibit protective effects against UVB-induced skin aging. Taken together, these findings underline the potential for BPLE and TCA to be utilized as anti-wrinkling agents and cosmetic ingredients, as they suppress UVB-induced MMP-1 expression.

  11. Honokiol, a phytochemical from the Magnolia plant, inhibits photocarcinogenesis by targeting UVB-induced inflammatory mediators and cell cycle regulators: development of topical formulation.

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    Vaid, Mudit; Sharma, Som D; Katiyar, Santosh K

    2010-11-01

    To develop newer and more effective chemopreventive agents for skin cancer, we assessed the effect of honokiol, a phytochemical from the Magnolia plant, on ultraviolet (UV) radiation-induced skin tumorigenesis using the SKH-1 hairless mouse model. Topical treatment of mice with honokiol in a hydrophilic cream-based topical formulation before or after UVB (180 mJ/cm(2)) irradiation resulted in a significant protection against photocarcinogenesis in terms of tumor multiplicity (28-60%, P skin samples from the tumor-bearing mice were analyzed for inflammatory mediators, cell cycle regulators and survival signals using immunostaining, western blotting and enzyme-linked immunosorbent assay. Treatment with honokiol significantly inhibited UVB-induced expression of cyclooxygenase-2, prostaglandin E(2) (P skin as well as in skin tumors. Western blot analysis revealed that honokiol: (i) inhibited the levels of cyclins D1, D2 and E and associated cyclin-dependent kinases (CDKs)2, CDK4 and CDK6, (ii) upregulated Cip/p21 and Kip/p27 and (iii) inhibited the levels of phosphatidylinositol 3-kinase and the phosphorylation of Akt at Ser(473) in UVB-induced skin tumors. Together, our results indicate that honokiol holds promise for the prevention of UVB-induced skin cancer by targeting inflammatory mediators, cell cycle regulators and cell survival signals in UVB-exposed skin.

  12. Inhibition of ribonucleic acid efflux from isolated SV40-3T3 cell nuclei by 3'-deoxyadenosine (cordycepin).

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    Agutter, P S; McCaldin, B

    1979-05-15

    The effect of 3'-deoxyadenosine (cordycepin) on mRNA efflux from isolated SV40-3T3 cell nuclei has been studied and compared with its effect on the nucleoside triphosphatase activity in the isolated nuclear envelope. Inhibition of mRNA efflux occurs rapidly, but is dependent on the presence of ATP. Half-maximal inhibition occurs with 40 microM-cordycepin. The effect is not simulated by 2'-deoxyadenosine or by actinomycin D, and adenosine provides a substantial degree of protection against it. Cordycepin does not directly inhibit the nucleoside triphosphatase. The stimulation of this enzyme by poly(A) is not affected unless the poly(A) and cordycepin are incubated together with nuclear lysate in the presence of ATP; in this case the stimulation is significantly reduced. Possible interpretations of these results and their relevance for understanding the system in vivo for nucleo-cytoplasmic messenger transport are discussed.

  13. Pinus densiflora extract protects human skin fibroblasts against UVB-induced photoaging by inhibiting the expression of MMPs and increasing type I procollagen expression

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    Hoe-Yune Jung

    2014-01-01

    Full Text Available Exposure to ultraviolet (UV light can cause skin photoaging, which is associated with upregulation of matrix metalloproteinases (MMPs and downregulation of collagen synthesis. It has been reported that MMPs, especially MMP-1, MMP-3 and MMP-9, decrease the elasticity of the dermis by degrading collagen. In this study, we assessed the effects of Pinus densiflora extract (PDE on photoaging and investigated its mechanism of action in human skin fibroblast (Hs68 cells after UVB exposure using real-time polymerase chain reaction, Western blot analysis, and enzymatic activity assays. PDE exhibited an antioxidant activity and inhibited elastase activities in vitro. We also found that PDE inhibited UVB-induced cytotoxicity, MMP-1 production and expression of MMP-1, -3 and -9 mRNA in Hs68 cells. In addition, PDE decreased UVB-induced MMP-2 activity and MMP-2 mRNA expression. Moreover, PDE prevented the decrease of type I procollagen mediated by exposure to UVB irradiation, an effect that is linked to the upregulation and downregulation of Smad3 and Smad7, respectively. Another effect of UV irradiation is to stimulate activator protein 1 (AP-1 activity via overexpression of c-Jun/c-Fos, which, in turn, upregulates MMP-1, -3, and -9. In this study, we found that PDE suppressed UV-induced c-Jun and c-Fos mRNA expression. Taken together, these results demonstrate that PDE regulates UVB-induced expression of MMPs and type I procollagen synthesis by inhibiting AP-1 activity and restoring impaired Smad signaling, suggesting that PDE may be useful as an effective anti-photoaging agent.

  14. Dietary grape seed proanthocyanidins inhibit UVB-induced oxidative stress and activation of mitogen-activated protein kinases and nuclear factor-kappaB signaling in in vivo SKH-1 hairless mice.

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    Sharma, Som D; Meeran, Syed M; Katiyar, Santosh K

    2007-03-01

    We have shown previously that dietary grape seed proanthocyanidins (GSP) inhibit UVB-induced photocarcinogenesis in mice. As UVB-induced oxidative stress and oxidative stress-mediated signaling has been implicated in photocarcinogenesis, this study was designed to investigate the effect of dietary GSPs on UVB-induced oxidative stress in in vivo SKH-1 hairless mice. Here, we report that provision of dietary GSPs (0.2 and 0.5%, w/w) to mice exposed to either acute UVB irradiation (120 mJ/cm(2)) or chronic irradiation of UVB inhibited depletion of glutathione peroxidase, catalase, and glutathione, and inhibited UVB-induced H(2)O(2), lipid peroxidation, protein oxidation, and nitric oxide in mouse skin. As UV-induced oxidative stress mediates activation of mitogen-activated protein kinase (MAPK) and nuclear factor-kappaB (NF-kappaB) signaling pathways, we determined the effect of dietary GSPs on these pathways. We observed that dietary GSPs inhibited UVB-induced phosphorylation of extracellular signal-regulated kinase 1/2, c-Jun-NH(2)-kinase, and p38 proteins of MAPK family, which seems to be mediated through reactivation of MAPK phosphatases. GSPs inhibited UVB-induced activation of NF-kappaB/p65 through inhibition of degradation of IkappaBalpha and activation of IkappaB kinase alpha (IKKalpha). As NF-kappaB-targeted genes play critical roles in inflammation and cellular proliferation, we assessed the effect of GSPs on proteins encoded by these genes. Dietary GSPs resulted in inhibition of the expression of proliferating cell nuclear antigen, cyclin D1, inducible nitric oxide synthase, and cyclooxygenase-2 in the skin. Collectively, our data show that GSPs have the ability to protect the skin from the adverse effects of UVB radiation via modulation of the MAPK and NF-kappaB signaling pathways and provide a molecular basis for the photoprotective effects of GSPs in an in vivo animal model.

  15. Inhibition of UVB-induced skin damage by exopolymers from Aureobasidium pullulans SM-2001 in hairless mice.

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    Kim, Kyung Hu; Park, Soo Jin; Lee, Young Joon; Lee, Ji Eun; Song, Chang Hyun; Choi, Seong Hun; Ku, Sae Kwang; Kang, Su Jin

    2015-02-01

    Because antioxidants from natural sources may be an effective approach to the treatment and prevention of UV radiation-induced skin damage, the effects of purified exopolymers from Aureobasidium pullulans SM-2001 ('E-AP-SM2001') were evaluated in UVB-induced hairless mice. E-AP-SM2001 consists of 1.7% β-1,3/1,6-glucan, fibrous polysaccharides and other organic materials, such as amino acids, and mono- and di-unsaturated fatty acids (linoleic and linolenic acids) and shows anti-osteoporotic and immunomodulatory effects, through antioxidant and anti-inflammatory mechanisms. Hairless mice were treated topically with vehicle, E-AP-SM2001 stock and two and four times diluted solutions once per day for 15 weeks against UVB irradiation (three times per week at 0.18 J/cm(2) ). The following parameters were evaluated in skin samples: myeloperoxidase (MPO) activity, cytokine levels [interleukin (IL)-1β and IL-10], endogenous antioxidant content (glutathione, GSH), malondialdehyde (MDA) levels, superoxide anion production; matrix metalloproteases (MMP-1, -9 and -13), GSH reductase and Nox2 (gp91phox) mRNA levels, and immunoreactivity for nitrotyrosine (NT), 4-hydroxynonenal (HNE), caspase-3, and cleaved poly(ADP-ribose) polymerase (PARP). Photoageing was induced by UVB irradiation through ROS-mediated inflammation, which was related to the depletion of endogenous antioxidants, activation of MMPs and keratinocyte apoptosis. Topical treatment with all three doses of E-AP-SM2001 and 5 nm myricetin attenuated the UV-induced depletion of GSH, activation of MMPs, production of IL-1β, the decrease in IL-10 and keratinocyte apoptosis. In this study, E-AP-SM2001 showed potent inhibitory effects against UVB-induced skin photoageing. Thus, E-AP-SM2001 may be useful as a functional ingredient in cosmetics, especially as a protective agent against UVB-induced skin photoageing.

  16. Fisetin inhibits UVB-induced cutaneous inflammation and activation of PI3K/AKT/NFκB signaling pathways in SKH-1 hairless mice†

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    Pal, Harish Chandra; Athar, Mohammad; Elmets, Craig A.; Afaq, Farrukh

    2014-01-01

    Solar ultraviolet B (UVB) radiation has been shown to induce inflammation, DNA damage, p53 mutations, and alterations in signaling pathways eventually leading to skin cancer. In the present study, we investigated whether fisetin reduces inflammatory responses and modulates PI3K/AKT/NFκB cell survival signaling pathways in UVB exposed SKH-1 hairless mouse skin. Mice were exposed to 180 mJ/cm2 of UVB radiation on alternate days for a total of seven exposures, and fisetin (250 and 500 nmol) was applied topically after 15 min of each UVB exposure. Fisetin treatment to UVB exposed mice resulted in decreased hyperplasia and reduced infiltration of inflammatory cells. Fisetin treatment also reduced inflammatory mediators such as COX-2, PGE2 as well as its receptors (EP1- EP4), and MPO activity. Furthermore, fisetin reduced the level of inflammatory cytokines TNFα, IL-1β and IL-6 in UVB exposed skin. Fisetin treatment also reduced cell proliferation markers as well as DNA damage as evidenced by increased expression of p53 and p21 proteins. Further studies revealed that fisetin inhibited UVB-induced expression of PI3K, phosphorylation of AKT, and activation of the NFκB signaling pathway in mouse skin. Overall, these data suggest that fisetin may be useful against UVB-induced cutaneous inflammation and DNA damage. PMID:25169110

  17. Fisetin inhibits UVB-induced cutaneous inflammation and activation of PI3K/AKT/NFκB signaling pathways in SKH-1 hairless mice.

    Science.gov (United States)

    Pal, Harish Chandra; Athar, Mohammad; Elmets, Craig A; Afaq, Farrukh

    2015-01-01

    Solar ultraviolet B (UVB) radiation has been shown to induce inflammation, DNA damage, p53 mutations and alterations in signaling pathways eventually leading to skin cancer. In this study, we investigated whether fisetin reduces inflammatory responses and modulates PI3K/AKT/NFκB cell survival signaling pathways in UVB-exposed SKH-1 hairless mouse skin. Mice were exposed to 180 mJ cm(-2) of UVB radiation on alternate days for a total of seven exposures, and fisetin (250 and 500 nmol) was applied topically after 15 min of each UVB exposure. Fisetin treatment to UVB-exposed mice resulted in decreased hyperplasia and reduced infiltration of inflammatory cells. Fisetin treatment also reduced inflammatory mediators such as COX-2, PGE2 as well as its receptors (EP1-EP4) and MPO activity. Furthermore, fisetin reduced the level of inflammatory cytokines TNFα, IL-1β and IL-6 in UVB-exposed skin. Fisetin treatment also reduced cell proliferation markers as well as DNA damage as evidenced by increased expression of p53 and p21 proteins. Further studies revealed that fisetin inhibited UVB-induced expression of PI3K, phosphorylation of AKT and activation of the NFκB signaling pathway in mouse skin. Overall, these data suggest that fisetin may be useful against UVB-induced cutaneous inflammation and DNA damage. © 2014 The American Society of Photobiology.

  18. Docosahexaenoic acid inhibits UVB-induced activation of NF-κB and expression of COX-2 and NOX-4 in HR-1 hairless mouse skin by blocking MSK1 signaling.

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    Mostafizur Rahman

    Full Text Available Exposure to ultraviolet-B (UVB radiation induces inflammation and photocarcinogenesis in mammalian skin. Docosahexaenoic acid (DHA, a representative ω-3 polyunsaturated fatty acid, has been reported to possess anti-inflammatory and chemopreventive properties. In the present study, we investigated the molecular mechanisms underlying the inhibitory effects of DHA on UVB-induced inflammation in mouse skin. Our study revealed that topical application of DHA prior to UVB irradiation attenuated the expression of cyclooxygenase-2 (COX-2 and NAD(PH:oxidase-4 (NOX-4 in hairless mouse skin. DHA pretreatment also attenuated UVB-induced DNA binding of nuclear factor-kappaB (NF-κB through the inhibition of phosphorylation of IκB kinase-α/β, phosphorylation and degradation of IκBα and nuclear translocation of p50 and p65. In addition, UVB-induced phosphorylation of p65 at the serine 276 residue was significantly inhibited by topical application of DHA. Irradiation with UVB induced phosphorylation of mitogen and stress-activated kinase-1 (MSK1, extracellular signal-regulated kinase (ERK and p38 mitogen-activated protein (MAP kinase, and all these events were attenuated by pretreatment with DHA. Blocking ERK and p38 MAP kinase signaling by U0126 and SB203580, respectively, diminished MSK1 phosphorylation in UVB-irradiated mouse skin. Pretreatment with H-89, a pharmacological inhibitor of MSK1, abrogated UVB-induced activation of NF-κB and the expression of COX-2 and NOX-4 in mouse skin. In conclusion, topically applied DHA inhibits the UVB-induced activation of NF-κB and the expression of COX-2 and NOX-4 by blocking the phosphorylation of MSK1, a kinase downstream of ERK and p38 MAP kinase, in hairless mouse skin.

  19. Cordycepin inhibits lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-α production via activating amp-activated protein kinase (AMPK) signaling.

    Science.gov (United States)

    Zhang, Jian-Li; Xu, Ying; Shen, Jie

    2014-07-08

    Tumor necrosis factor (TNF)-α is elevated during the acute phase of Kawasaki disease (KD), which damages vascular endothelial cells to cause systemic vasculitis. In the current study, we investigated the potential role of cordycepin on TNFα expression in both lipopolysaccharide (LPS)-stimulated macrophages and ex vivo cultured peripheral blood mononuclear cells (PBMCs) of KD patients. We found that cordycepin significantly suppressed LPS-induced TNFα expression and production in mouse macrophages (RAW 264.7 cells and bone marrow-derived macrophages (BMDMs)). Meanwhile, cordycepin alleviated TNFα production in KD patients' PBMCs. PBMCs from healthy controls had a much lower level of basal TNF-α content than that of KD patients. LPS-induced TNF-α production in healthy controls' PBMCs was also inhibited by cordycepin. For the mechanism study, we discovered that cordycepin activated AMP-activated protein kinase (AMPK) signaling in both KD patients' PBMCs and LPS-stimulated macrophages, which mediated cordycepin-induced inhibition against TNFα production. AMPK inhibition by its inhibitor (compound C) or by siRNA depletion alleviated cordycepin's effect on TNFα production. Further, we found that cordycepin inhibited reactive oxygen species (ROS) production and nuclear factor kappa B (NF-κB) activation in LPS-stimulate RAW 264.7 cells or healthy controls' PBMCs. PBMCs of KD patients showed higher basal level of ROS and NF-κB activation, which was also inhibited by cordycepin co-treatment. In conclusion, our data showed that cordycepin inhibited TNFα production, which was associated with AMPK activation as well as ROS and NF-κB inhibition. The results of this study should have significant translational relevance in managing this devastating disease.

  20. Germacrane sesquiterpenes isolated from the rhizome of Curcuma xanthorrhiza Roxb. inhibit UVB-induced upregulation of MMP-1, -2, and -3 expression in human keratinocytes.

    Science.gov (United States)

    Park, Ji-Hae; Mohamed, Mohamed Antar Aziz; Jung, Ye-Jin; Shrestha, Sabina; Lee, Tae Hoon; Lee, Chang-Ho; Han, Daeseok; Kim, Jiyoung; Baek, Nam-In

    2015-10-01

    Four sesquiterpenes were isolated from the rhizome of Curcuma xanthorrhiza Roxb.: furanodiene (1), germacrone (2), furanodienone (3), and 13-hydroxygermacrone (4). Importantly, this was the first time compounds 1 and 4 were isolated from this plant. The chemical structures of these compounds were determined using 1D- and 2D-nuclear magnetic resonance, infrared spectroscopy, and electron ionization mass spectrometry analyses. Among the isolated compounds, compounds 2 and 4 inhibited UVB-induced upregulation of the mRNA and protein expression levels of MMP-1, MMP-2, and MMP-3 in human keratinocytes (HaCaT). Moreover, this upregulation occurred in a dose-dependent manner over the range of 1-10 μM for each compound.

  1. Cordycepin Inhibits Lipopolysaccharide (LPS-Induced Tumor Necrosis Factor (TNF-α Production via Activating AMP-Activated Protein Kinase (AMPK Signaling

    Directory of Open Access Journals (Sweden)

    Jian-Li Zhang

    2014-07-01

    Full Text Available Tumor necrosis factor (TNF-α is elevated during the acute phase of Kawasaki disease (KD, which damages vascular endothelial cells to cause systemic vasculitis. In the current study, we investigated the potential role of cordycepin on TNFα expression in both lipopolysaccharide (LPS-stimulated macrophages and ex vivo cultured peripheral blood mononuclear cells (PBMCs of KD patients. We found that cordycepin significantly suppressed LPS-induced TNFα expression and production in mouse macrophages (RAW 264.7 cells and bone marrow-derived macrophages (BMDMs. Meanwhile, cordycepin alleviated TNFα production in KD patients’ PBMCs. PBMCs from healthy controls had a much lower level of basal TNF-α content than that of KD patients. LPS-induced TNF-α production in healthy controls’ PBMCs was also inhibited by cordycepin. For the mechanism study, we discovered that cordycepin activated AMP-activated protein kinase (AMPK signaling in both KD patients’ PBMCs and LPS-stimulated macrophages, which mediated cordycepin-induced inhibition against TNFα production. AMPK inhibition by its inhibitor (compound C or by siRNA depletion alleviated cordycepin’s effect on TNFα production. Further, we found that cordycepin inhibited reactive oxygen species (ROS production and nuclear factor kappa B (NF-κB activation in LPS-stimulate RAW 264.7 cells or healthy controls’ PBMCs. PBMCs of KD patients showed higher basal level of ROS and NF-κB activation, which was also inhibited by cordycepin co-treatment. In conclusion, our data showed that cordycepin inhibited TNFα production, which was associated with AMPK activation as well as ROS and NF-κB inhibition. The results of this study should have significant translational relevance in managing this devastating disease.

  2. Constitutive expression of MC1R in HaCaT keratinocytes inhibits basal and UVB-induced TNF-alpha production.

    Science.gov (United States)

    Garcin, Geneviève; Le Gallic, Lionel; Stoebner, Pierre-Emmanuel; Guezennec, Anne; Guesnet, Joelle; Lavabre-Bertrand, Thierry; Martinez, Jean; Meunier, Laurent

    2009-01-01

    Alpha-melanocyte stimulating hormone (alpha-MSH) binds to melanocortin-1 receptor (MC1R) on melanocytes to stimulate pigmentation and modulate various cutaneous inflammatory responses. MC1R expression is not restricted to melanocytic cells and may be induced in keratinocytes after UVB exposure. We hypothesized that MC1R signaling in keratinocytes, wherein basal conditions are barely expressed, may modulate mediators of inflammation, such as nuclear factor-kappa B (NF-kappaB) and tumor necrosis factor-alpha (TNF-alpha). Therefore, we generated HaCaT cells that stably express human MC1R or the Arg151Cys (R151C) nonfunctional variant. We demonstrate that: (1) the constitutive activity of MC1R results in elevated intracellular cAMP level, reduced NF-kappaB activity and decreased TNF-alpha transcription; (2) binding of alpha-MSH to MC1R and the subsequent increase in cAMP production do not inhibit TNFalpha-mediated NF-kappaB activation; (3) MC1R signaling is sufficient to strongly inhibit UVB-induced TNF-alpha expression and this inhibitory effect is further enhanced by alpha-MSH stimulation. Our findings suggest that the constitutive activity of the G-protein-coupled MC1R in keratinocytes may contribute to the modulation of inflammatory events and immune response induced by UV light.

  3. Caffeic Acid Inhibits UVB-induced Inflammation and Photocarcinogenesis Through Activation of Peroxisome Proliferator-activated Receptor-γ in Mouse Skin.

    Science.gov (United States)

    Balupillai, Agilan; Prasad, Rajendra N; Ramasamy, Karthikeyan; Muthusamy, Ganesan; Shanmugham, Mohana; Govindasamy, Kanimozhi; Gunaseelan, Srithar

    2015-11-01

    In this study, the effect of caffeic acid (CA) on both acute and chronic UVB-irradiation-induced inflammation and photocarcinogenesis was investigated in Swiss albino mice. Animals were exposed to 180 mJ cm(-2) of UVB once daily for 10 consecutive days and thrice weekly for 30 weeks for acute and chronic study respectively. UVB exposure for 10 consecutive days showed edema formation, increased lipid peroxidation and decreased antioxidant status with activation of inflammatory molecules such as TNF-α, IL-6, COX-2 and NF-κB. However, CA (15 mg per kg.b.wt.) administration before each UVB exposure decreased lipid peroxidation, inflammatory markers expression and enhanced antioxidant status probably through the activation of peroxisome proliferator-activated receptors (PPARγ) in the mice skin. PPARγ is considered a potential target for photochemoprevention because it inhibits UVB-mediated inflammatory responses. In this study, UVB exposure for 30 weeks caused squamous cell carcinoma and upregulation of iNOS, VEGF and TGF-β and downregulation of p53 and tumor incidence in the mice skin. Both topical (CAT) and intraperitoneal (CAIP) treatment before each UVB exposure downregulates iNOS, VEGF, TGF-β, upregulates p53 and reduces tumors multiplicity in the mice skin. Thus, CA offers protection against UVB-induced photocarcinogenesis probably through activation of anti-inflammatory transcription factor PPARγ in the mice.

  4. Inhibition of ultraviolet B (UVB) induced apoptosis in A431 cells by mimosine is not dependent on cell cycle arrest

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    Cliche, D.O.; Girouard, S.; Bissonnette, N.; Hunting, D.J. [CIHR Group in the Radiation Sciences, Faculte de Medecine, Univ. de Sherbrooke, Sherbrooke, Quebec (Canada)

    2002-07-01

    Ultraviolet (UV) radiation is a strong apoptotic trigger in many cell types. We have. previously reported that a plant amino acid, mimosine ({beta}-[N-(3-hydroxy-4-pyridone)]-{alpha}-aminopropionic acid), with a well-known reversible G1 cell cycle arrest activity can inhibit apoptosis induced by UV irradiation and RNA polymerase II blockage in human A431 cells. Here, apoptosis was measured with a fluorimetric caspase activation assay. Interestingly, the protective state was effective up to 24 h following removal of mimosine from the culture medium while cells were progressing in the cell cycle. Our results demonstrate that the protective effect of mimosine against UV-induced apoptosis can be dissociated from its G1 cell-cycle arrest activity. (author)

  5. Exceptionally high protection of photocarcinogenesis by topical application of (--)-epigallocatechin-3-gallate in hydrophilic cream in SKH-1 hairless mouse model: relationship to inhibition of UVB-induced global DNA hypomethylation.

    Science.gov (United States)

    Mittal, Anshu; Piyathilake, Chandrika; Hara, Yukihiko; Katiyar, Santosh K

    2003-01-01

    (--)-Epigallocatechin-3-gallate (EGCG) has been shown to have potent antiphotocarcinogenic activity, but it was required to develop a cream-based formulation for topical application. For topical application, we tested hydrophilic cream as a vehicle for EGCG. Treatment with EGCG ( approximately 1 mg/cm(2) skin area) in hydrophilic cream resulted in exceptionally high protection against photocarcinogenesis when determined in terms of tumor incidence, tumor multiplicity, and tumor size in a SKH-1 hairless mouse model. EGCG also inhibited malignant transformation of ultraviolet B (UVB)-induced papillomas to carcinomas. In order to determine the mechanism of prevention of photocarcinogenesis, we determined the effect of EGCG on global DNA methylation pattern using monoclonal antibodies against 5-methyl cytosine and DNA methyltransferase in the long-term UV-irradiated skin because altered DNA methylation silencing is recognized as a molecular hallmark of human cancer. We found that treatment with EGCG resulted in significant inhibition of UVB-induced global DNA hypomethylation pattern. Long-term application of EGCG did not show any apparent sign of toxicity in mice when determined in terms of skin appearance, lean mass, total bone mineral content, and total bone mineral density but showed reduction in fat mass when analyzed using dual-energy X-ray absorptiometry. These data suggest that hydrophilic cream could be a suitable vehicle for topical application of EGCG, and that EGCG is a promising candidate for future cancer therapies based on its influence on the epigenetic pathway.

  6. Exceptionally High Protection of Photocarcinogenesis by Topical Application of (--Epi gal locatechin-3-Gal late in Hydrophilic Cream in SKH-1 Hairless Mouse Model: Relationship to Inhibition of UVB-Induced Global DNA Hypomethylation

    Directory of Open Access Journals (Sweden)

    Anshu Mittal

    2003-11-01

    Full Text Available (--Epigallocatechin-3-gal late (EGCG has been shown to have potent antiphotocarcinogenic activity, but it was required to develop a cream-based formulation for topical application. For topical application, we tested hydrophilic cream as a vehicle for EGCG. Treatment with EGCG (≈ 1 mg/cm2 skin area in hydrophilic cream resulted in exceptionally high protection against photocarcinogenesis when determined in terms of tumor incidence, tumor multiplicity, and tumor size in a SKI-11-11 hairless mouse model. EGCG also inhibited malignant transformation of ultraviolet B (UVB-induced papillomas to carcinomas. In order to determine the mechanism of prevention of photocarcinogenesis, we determined the effect of EGCG on global DNA methylation pattern using monoclonal antibodies against 5-methyl cytosine and DNA methyltransferase in the long-term UV-irradiated skin because altered DNA methylation silencing is recognized as a molecular hallmark of human cancer. We found that treatment with EGCG resulted in significant inhibition of UVBinduced global DNA hypomethylation pattern. Longterm application of EGCG did not show any apparent sign of toxicity in mice when determined in terms of skin appearance, lean mass, total bone mineral content, and total bone mineral density but showed reduction in fat mass when analyzed using dual-energy X-ray absorptiometry. These data suggest that hydrophilic cream could be a suitable vehicle for topical application of EGCG, and that EGCG is a promising candidate for future cancer therapies based on its influence on the epigenetic pathway.

  7. The novel PPAR α/γ dual agonist MHY 966 modulates UVB-induced skin inflammation by inhibiting NF-κB activity.

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    Min Hi Park

    Full Text Available Ultraviolet B (UVB; 290~320nm irradiation-induced lipid peroxidation induces inflammatory responses that lead to skin wrinkle formation and epidermal thickening. Peroxisome proliferator-activated receptor (PPAR α/γ dual agonists have the potential to be used as anti-wrinkle agents because they inhibit inflammatory response and lipid peroxidation. In this study, we evaluated the function of 2-bromo-4-(5-chloro-benzo[d]thiazol-2-yl phenol (MHY 966, a novel synthetic PPAR α/γ dual agonist, and investigated its anti-inflammatory and anti-lipid peroxidation effects. The action of MHY 966 as a PPAR α/γ dual agonist was also determined in vitro by reporter gene assay. Additionally, 8-week-old melanin-possessing hairless mice 2 (HRM2 were exposed to 150 mJ/cm(2 UVB every other day for 17 days and MHY 966 was simultaneously pre-treated every day for 17 days to investigate the molecular mechanisms involved. MHY 966 was found to stimulate the transcriptional activities of both PPAR α and γ. In HRM2 mice, we found that the skins of mice exposed to UVB showed significantly increased pro-inflammatory mediator levels (NF-κB, iNOS, and COX-2 and increased lipid peroxidation, whereas MHY 966 co-treatment down-regulated these effects of UVB by activating PPAR α and γ. Thus, the present study shows that MHY 966 exhibits beneficial effects on inflammatory responses and lipid peroxidation by simultaneously activating PPAR α and γ. The major finding of this study is that MHY 966 demonstrates potential as an agent against wrinkle formation associated with chronic UVB exposure.

  8. The Protecting Effect of Deoxyschisandrin and Schisandrin B on HaCaT Cells against UVB-Induced Damage.

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    Wei Hou

    Full Text Available Schisandra chinensis is a traditional Chinese medicine that has multiple biological activities, including antioxidant, anticancer, tonic, and anti-aging effects. Deoxyschisandrin (SA and schisandrin B (SB, the two major lignans isolated from S. chinensis, exert high antioxidant activities in vitro and in vivo by scavenging free radicals, such as reactive oxygen species (ROS. Ultraviolet B-ray (UVB radiation induces the production of ROS and DNA damage, which eventually leads to cell death by apoptosis. However, it is unknown whether SA or SB protects cells against UVB-induced cellular DNA damage. Our study showed that both SA and SB effectively protected HaCaT cells from UVB-induced cell death by antagonizing UVB-mediated production of ROS and induction of DNA damage. Our results showed that both SA and SB significantly prevented UVB-induced loss of cell viability using 3-(4, 5-dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide (MTT assays. Dichloro-dihydro-fluorescein diacetate (DCFH-DA assays showed that the production of ROS following UVB exposure was inhibited by treatment with SA and SB. Moreover, SA and SB decreased the UVB-induced DNA damage in HaCaT cells by comet assays. In addition, SA and SB also prevented UVB-induced cell apoptosis and the cleavage of caspase-3, caspase-8 and caspase-9. In a word, our results imply that the antioxidants SA and SB could protect cells from UVB-induced cell damage via scavenging ROS.

  9. The Protecting Effect of Deoxyschisandrin and Schisandrin B on HaCaT Cells against UVB-Induced Damage.

    Science.gov (United States)

    Hou, Wei; Gao, Wei; Wang, Datao; Liu, Qingxiu; Zheng, Siwen; Wang, Yingping

    2015-01-01

    Schisandra chinensis is a traditional Chinese medicine that has multiple biological activities, including antioxidant, anticancer, tonic, and anti-aging effects. Deoxyschisandrin (SA) and schisandrin B (SB), the two major lignans isolated from S. chinensis, exert high antioxidant activities in vitro and in vivo by scavenging free radicals, such as reactive oxygen species (ROS). Ultraviolet B-ray (UVB) radiation induces the production of ROS and DNA damage, which eventually leads to cell death by apoptosis. However, it is unknown whether SA or SB protects cells against UVB-induced cellular DNA damage. Our study showed that both SA and SB effectively protected HaCaT cells from UVB-induced cell death by antagonizing UVB-mediated production of ROS and induction of DNA damage. Our results showed that both SA and SB significantly prevented UVB-induced loss of cell viability using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assays. Dichloro-dihydro-fluorescein diacetate (DCFH-DA) assays showed that the production of ROS following UVB exposure was inhibited by treatment with SA and SB. Moreover, SA and SB decreased the UVB-induced DNA damage in HaCaT cells by comet assays. In addition, SA and SB also prevented UVB-induced cell apoptosis and the cleavage of caspase-3, caspase-8 and caspase-9. In a word, our results imply that the antioxidants SA and SB could protect cells from UVB-induced cell damage via scavenging ROS.

  10. Cordycepin attenuates traumatic brain injury-induced impairments of blood-brain barrier integrity in rats.

    Science.gov (United States)

    Yuan, Jing; Wang, Aihua; He, Yan; Si, Zhihua; Xu, Shan; Zhang, Shanchao; Wang, Kun; Wang, Dawei; Liu, Yiming

    2016-10-01

    Loss of blood-brain barrier (BBB) integrity is a downstream event caused by traumatic brain injury (TBI). BBB integrity is affected by certain physiological conditions, including inflammation and oxidative stress. Cordycepin is a susbtance with anti-inflammatory and anti-oxidative effects. Therefore, it is necessary to investigate whether cordycepin affects TBI-induced impairments of BBB integrity. Using TBI rats as the in vivo model and applying multiple techniques, including stroke severity evaluation, Evans blue assessment, quantitative real-time PCR, Western blotting and ELISA, we investigated the dose-dependent protective effects of cordycepin on the TBI-induced impairments of BBB integrity. Cordycepin treatment attenuated the TBI-induced impairments in a dose-dependent manner, and played a role in protecting BBB integrity. Cordycepin was able to alleviate TBI-induced loss of tight junction proteins zonula occludens protein-1 (ZO-1) and occludin, which are important for BBB integrity. Moreover, cordycepin suppressed pro-inflammatory factors, including IL-1β, iNOS, MPO and MMP-9, and promoted anti-inflammation-associated factors arginase 1 and IL-10. Furthermore, cordycepin inhibited NADPH oxidase (NOX) expression and activity following TBI, probably through NOX1, but not NOX2 and NOX4. Cordycepin has protective effects against brain damages induced by TBI. The protection of cordycepin on BBB integrity was probably achieved through recovery of tight junction proteins, inhibition of local inflammation, and prevention of NOX activity. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Quercitrin protects skin from UVB-induced oxidative damage

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    Yin, Yuanqin [Cancer Institute, The First Affiliated Hospital, China Medical University, Shenyang (China); Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY (United States); Li, Wenqi; Son, Young-Ok; Sun, Lijuan; Lu, Jian; Kim, Donghern; Wang, Xin [Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY (United States); Yao, Hua [Department of Stomatology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang (China); Wang, Lei; Pratheeshkumar, Poyil; Hitron, Andrew J. [Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY (United States); Luo, Jia [Department of Internal Medicine, University of Kentucky, 800 Rose Street, Lexington, KY (United States); Gao, Ning [Department of Pharmacognos, College of Pharmacy, 3rd Military Medical University, Chongqing (China); Shi, Xianglin [Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY (United States); Zhang, Zhuo, E-mail: zhuo.zhang@uky.edu [Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY (United States)

    2013-06-01

    Exposure of the skin to ultraviolet B (UVB) radiation causes oxidative damage to skin, resulting in sunburn, photoaging, and skin cancer. It is generally believed that the skin damage induced by UV irradiation is a consequence of generation of reactive oxygen species (ROS). Recently, there is an increased interest in the use of natural products as chemopreventive agents for non-melanoma skin cancer (NMSC) due to their antioxidants and anti-inflammatory properties. Quercitrin, glycosylated form of quercetin, is the most common flavonoid in nature with antioxidant properties. The present study investigated the possible beneficial effects of quercitrin to inhibit UVB irradiation-induced oxidative damage in vitro and in vivo. Our results showed that quercitrin decreased ROS generation induced by UVB irradiation in JB6 cells. Quercitrin restored catalase expression and GSH/GSSG ratio reduced by UVB exposure, two major antioxidant enzymes, leading to reductions of oxidative DNA damage and apoptosis and protection of the skin from inflammation caused by UVB exposure. The present study demonstrated that quercitrin functions as an antioxidant against UVB irradiation-induced oxidative damage to skin. - Highlights: • Oxidative stress plays a key role in UV-induced cell and tissue injuries. • Quercitrin decreases ROS generation and restores antioxidants irradiated by UVB. • Quercitrin reduces UVB-irradiated oxidative DNA damage, apoptosis, and inflammation. • Quercitrin functions as an antioxidant against UVB-induced skin injuries.

  12. Cordycepin-induced apoptosis and autophagy in breast cancer cells are independent of the estrogen receptor

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Sunga [Department of Physiology, School of Medicine, Chungnam National University, Daejeon, 301747 (Korea, Republic of); Lim, Mi-Hee [Department of Biochemistry, Kangwon National University, Gangwon-do, 200701 (Korea, Republic of); Kim, Ki Mo [Diabetic Complications Research Center, Division of Traditional Korean Medicine (TKM) Integrated Research, Korea Institute of Oriental Medicine (KIOM), 305811, Daejeon (Korea, Republic of); Jeon, Byeong Hwa [Department of Physiology, School of Medicine, Chungnam National University, Daejeon, 301747 (Korea, Republic of); Song, Won O. [Department of Food Science and Human Nutrition, Michigan State University, East Lansing, MI 48824 (United States); Kim, Tae Woong, E-mail: tawkim@kangwon.ac.kr [Department of Biochemistry, Kangwon National University, Gangwon-do, 200701 (Korea, Republic of)

    2011-12-15

    Cordycepin (3-deoxyadenosine), found in Cordyceps spp., has been known to have many therapeutic effects including immunomodulatory, anti-inflammatory, antimicrobial, and anti-aging effects. Moreover, anti-tumor and anti-metastatic effects of cordycepin have been reported, but the mechanism causing cancer cell death is poorly characterized. The present study was designed to investigate whether the mechanisms of cordycepin-induced cell death were associated with estrogen receptor in breast cancer cells. Exposure of both MDA-MB-231 and MCF-7 human breast cancer cells to cordycepin resulted in dose-responsive inhibition of cell growth and reduction in cell viability. The cordycepin-induced cell death in MDA-MB-231 cells was associated with several specific features of the mitochondria-mediated apoptotic pathway, which was confirmed by DNA fragmentation, TUNEL, and biochemical assays. Cordycepin also caused a dose-dependent increase in mitochondrial translocation of Bax, triggering cytosolic release of cytochrome c and activation of caspases-9 and -3. Interestingly, MCF-7 cells showed autophagy-associated cell death, as observed by the detection of an autophagosome-specific protein and large membranous vacuole ultrastructure morphology in the cytoplasm. Cordycepin-induced autophagic cell death has applications in treating MCF-7 cells with apoptotic defects, irrespective of the ER response. Although autophagy has a survival function in tumorigenesis of some cancer cells, autophagy may be important for cordycepin-induced MCF-7 cell death. In conclusion, the results of our study demonstrate that cordycepin effectively kills MDA-MB-231 and MCF-7 human breast cancer cell lines in culture. Hence, further studies should be conducted to determine whether cordycepin will be a clinically useful, ER-independent, chemotherapeutic agent for human breast cancer. -- Highlights: Black-Right-Pointing-Pointer We studied the mechanism which cordycepin-induced cell death association with

  13. Nuclear DNA damage-triggered NLRP3 inflammasome activation promotes UVB-induced inflammatory responses in human keratinocytes

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    Hasegawa, Tatsuya, E-mail: tatsuya.hasegawa@to.shiseido.co.jp; Nakashima, Masaya; Suzuki, Yoshiharu

    2016-08-26

    Ultraviolet (UV) radiation in sunlight can result in DNA damage and an inflammatory reaction of the skin commonly known as sunburn, which in turn can lead to cutaneous tissue disorders. However, little has been known about how UV-induced DNA damage mediates the release of inflammatory mediators from keratinocytes. Here, we show that UVB radiation intensity-dependently increases NLRP3 gene expression and IL-1β production in human keratinocytes. Knockdown of NLRP3 with siRNA suppresses UVB-induced production of not only IL-1β, but also other inflammatory mediators, including IL-1α, IL-6, TNF-α, and PGE{sub 2}. In addition, inhibition of DNA damage repair by knockdown of XPA, which is a major component of the nucleotide excision repair system, causes accumulation of cyclobutane pyrimidine dimer (CPD) and activation of NLRP3 inflammasome. In vivo immunofluorescence analysis confirmed that NLRP3 expression is also elevated in UV-irradiated human epidermis. Overall, our findings indicate that UVB-induced DNA damage initiates NLRP3 inflammasome activation, leading to release of various inflammatory mediators from human keratinocytes. - Highlights: • UVB radiation induces NLRP3 inflammasome activation in human keratinocytes. • NLRP3 knockdown suppresses production of UVB-induced inflammatory mediators. • UVB-induced DNA damage triggers NLRP3 inflammasome activation. • NLRP3 expression in human epidermis is elevated in response to UV radiation.

  14. Antagonizing effects and mechanisms of afzelin against UVB-induced cell damage.

    Directory of Open Access Journals (Sweden)

    Seoung Woo Shin

    Full Text Available Ultraviolet (UV radiation induces DNA damage, oxidative stress, and inflammatory processes in human keratinocytes, resulting in skin inflammation, photoaging, and photocarcinogenesis. Adequate protection of skin against the harmful effects of UV irradiation is essential. Therefore, in this study, we investigated the protective effects of afzelin, one of the flavonoids, against UV irradiation in human keratinocytes and epidermal equivalent models. Spectrophotometric measurements revealed that the afzelin extinction maxima were in the UVB and UVA range, and UV transmission below 376 nm was <10%, indicating UV-absorbing activity of afzelin. In the phototoxicity assay using the 3T3 NRU phototoxicity test (3T3-NRU-PT, afzelin presented a tendency to no phototoxic potential. In addition, in order to investigate cellular functions of afzelin itself, cells were treated with afzelin after UVB irradiation. In human keratinocyte, afzelin effectively inhibited the UVB-mediated increase in lipid peroxidation and the formation of cyclobutane pyrimidine dimers. Afzelin also inhibited UVB-induced cell death in human keratinocytes by inhibiting intrinsic apoptotic signaling. Furthermore, afzelin showed inhibitory effects on UVB-induced release of pro-inflammatory mediators such as interleukin-6, tumor necrosis factor-α, and prostaglandin-E2 in human keratinocytes by interfering with the p38 kinase pathway. Using an epidermal equivalent model exposed to UVB radiation, anti-apoptotic activity of afzelin was also confirmed together with a photoprotective effect at the morphological level. Taken together, our results suggest that afzelin has several cellular activities such as DNA-protective, antioxidant, and anti-inflammatory as well as UV-absorbing activity and may protect human skin from UVB-induced damage by a combination of UV-absorbing and cellular activities.

  15. Langerhans Cells Facilitate UVB-induced Epidermal Carcinogenesis

    Science.gov (United States)

    Lewis, Julia M.; Bürgler, Christina D.; Freudzon, Marianna; Golubets, Kseniya; Gibson, Juliet F.; Filler, Renata B.; Girardi, Michael

    2015-01-01

    Ultraviolet B (UVB) light is considered the major environmental inducer of human keratinocyte DNA mutations, including within the tumor-suppressor gene p53, and chronic exposure is associated with cutaneous squamous cell carcinoma (SCC) formation. Langerhans cells (LC) comprise a dendritic network within the suprabasilar epidermis, yet the role of LC in UVB-induced carcinogenesis is largely unknown. Herein, we show that LC-intact epidermis develops UVB-induced tumors more readily than LC-deficient epidermis. While levels of epidermal cyclopyrimidine dimers (CPD) following acute UVB exposure are equivalent in the presence or absence of LC, chronic UVB-induced p53 mutant clonal islands expand more readily in association with LC which remain largely intact and are preferentially found in proximity to the expanding mutant keratinocyte populations. The observed LC facilitation of mutant p53 clonal expansion is completely αβ and γδ T-cell independent, and is associated with increased intraepidermal expression of interleukin (IL)-22 and the presence of group 3 innate lymphoid cells (ILC3). These data demonstrate that LC play a key role in UVB-induced cutaneous carcinogenesis, and suggest that LC locally stimulate keratinocyte proliferation and innate immune cells that provoke tumor outgrowth. PMID:26053049

  16. Effect of Cordycepin-Enriched WIB801C from Cordyceps militaris Suppressing Fibrinogen Binding to Glycoprotein IIb/IIIa

    Science.gov (United States)

    Lee, Dong-Ha; Kim, Hyun-Hong; Lim, Deok Hwi; Kim, Jong-Lae; Park, Hwa-Jin

    2015-01-01

    In this study, we investigated the effects of cordycepin-enriched (CE)-WIB801C, a n-butanol extract of Cordyceps militaris-hypha on collagen-stimulated platelet aggregation. CE-WIB801C dose dependently inhibited collagen-induced platelet aggregation, and had a synergistic effect together with cordycepin (W-cordycepin) from CE-WIB801C on the inhibition of collagen-induced platelet aggregation. CE-WIB801C and cordycepin stimulated the phosphorylation of VASP (Ser157) and the dephosphorylation of PI3K and Akt, and inhibited the binding of fibrinogen to glycoprotein IIb/IIIa (αIIb/β3) and the release of ATP and serotonin in collagen-induced platelet aggregation. A-kinase inhibitor Rp-8-Br-cAMPS reduced CE-WIB801C-, and cordycepin-increased VASP (Ser157) phosphorylation, and increased CE-WIB801C-, and cordycepin-inhibited the fibrinogen binding to αIIb/β3. Therefore, we demonstrate that CE-WIB801C-, and cordycepin-inhibited fibrinogen binding to αIIb/β3 are due to stimulation of cAMP-dependent phosphorylation of VASP (Ser157), and inhibition of PI3K/Akt phosphorylation. These results strongly indicate that CE-WIB801C and cordycepin may have preventive or therapeutic potential for platelet aggregation-mediated diseases, such as thrombosis, myocardial infarction, atherosclerosis, and ischemic cerebrovascular disease. PMID:25593645

  17. Cordycepin regulates GSK-3β/β-catenin signaling in human leukemia cells.

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    Bor-Sheng Ko

    Full Text Available BACKGROUND: Leukemia stem cells (LSCs are a limitless cell source for the initiation and maintenance of leukemia. Activation of the Wnt/β-catenin pathway is required for the survival and development of LSCs. Therefore, targeting β-catenin is considered a therapeutic strategy for the treatment of leukemia. The goal of this study was to explore whether cordycepin, an active component of the traditional medicine Cordyceps sinensis, regulates β-catenin expression in leukemia cells. METHODOLOGY AND PRINCIPAL FINDINGS: In this study, we found that cordycepin significantly suppressed cell proliferation in all malignant cancer cells, including U937, K562, A549, HepG2, SK-Hep1 and MCF7 in a dose-dependent manner. However, cordycepin reduced β-catenin levels in U937, K562 and THP1 leukemia cells and had no effect on other solid cancer cells. In addition, treatment with cordycepin significantly suppressed leukemia colony formation in soft agar assay. Cordycepin enhanced proteasome-dependent degradation and inhibited nuclear translocation of β-catenin in leukemia cells. Cordycepin-reduced β-catenin stability was restored by the addition of a pharmacological inhibitor of GSK-3β, indicating that cordycepin-suppressed β-catenin stability is mediated by the activation of GSK-3β. Furthermore, cordycepin abolished the effect of Wnt3a-induced β-catenin in leukemia cells. In addition, cordycepin-impaired β-catenin is regulated by Akt activation but is not significantly influenced by AMPK or mTOR signal pathways. SIGNIFICANCE: Our findings show for the first time that codycepin selectively reduces β-catenin stability in leukemia but not in other solid tumor cells. This suppressive effect is mediated by regulating GSK-3β. A synergistic combination of cordycepin with other treatments should be used as a novel strategy to eradicate leukemia via elimination of LSCs.

  18. Layered Double Hydroxide as Cordycepin Delivery Nanocarrier

    Institute of Scientific and Technical Information of China (English)

    Qin Zheng YANG; Jing YANG; Chang Kai ZHANG

    2006-01-01

    Layered double hydroxide was investigated as cordycepin delivery nanocarrier for the first time in this study. Negatively charged biomolecule-cordycepin was intercalated in the gallery spaces of [Mg-Al-NO3], which was confirmed by the results of X-ray diffraction and electrophoretic mobility. Cell experiment suggested that the new bio-LDH nanohybrid could prevent cordycepin decomposition by adenosine deaminase. This new formulation could possibly be used as a novel form cordycepin intravenous injection.

  19. Chemopreventive apigenin controls UVB-induced cutaneous proliferation and angiogenesis through HuR and thrombospondin-1.

    Science.gov (United States)

    Tong, Xin; Mirzoeva, Salida; Veliceasa, Dorina; Bridgeman, Bryan B; Fitchev, Philip; Cornwell, Mona L; Crawford, Susan E; Pelling, Jill C; Volpert, Olga V

    2014-11-30

    Plant flavonoid apigenin prevents and inhibits UVB-induced carcinogenesis in the skin and has strong anti-proliferative and anti-angiogenic properties. Here we identify mechanisms, by which apigenin controls these oncogenic events. We show that apigenin acts, at least in part, via endogenous angiogenesis inhibitor, thrombospondin-1 (TSP1). TSP1 expression by the epidermal keratinocytes is potently inhibited by UVB. It inhibits cutaneous angiogenesis and UVB-induced carcinogenesis. We show that apigenin restores TSP1 in epidermal keratinocytes subjected to UVB and normalizes proliferation and angiogenesis in UVB-exposed skin. Importantly, reconstituting TSP1 anti-angiogenic function in UVB-irradiated skin with a short bioactive peptide mimetic representing exclusively its anti-angiogenic domain reproduced the anti-proliferative and anti-angiogenic effects of apigenin. Cox-2 and HIF-1α are important mediators of angiogenesis. Both apigenin and TSP1 peptide mimetic attenuated their induction by UVB. Finally we identified the molecular mechanism, whereby apigenin did not affect TSP1 mRNA, but increased de novo protein synthesis. Knockdown studies implicated the RNA-binding protein HuR, which controls mRNA stability and translation. Apigenin increased HuR cytoplasmic localization and physical association with TSP1 mRNA causing de novo TSP1 synthesis. HuR cytoplasmic localization was, in turn, dependent on CHK2 kinase. Together, our data provide a new mechanism, by which apigenin controls UVB-induced carcinogenesis.

  20. Nitric oxide-releasing sulindac is a novel skin cancer chemopreventive agent for UVB-induced photocarcinogenesis.

    Science.gov (United States)

    Chaudhary, Sandeep C; Singh, Tripti; Kapur, Puneet; Weng, Zhiping; Arumugam, Aadithya; Elmets, Craig A; Kopelovich, Levy; Athar, Mohammad

    2013-05-01

    Nitric oxide (NO)-releasing non-steroidal anti-inflammatory drugs (NO-NSAIDs) which have been synthesized to reduce gastro-intestinal and cardiovascular toxicities of NSAIDs, possess anti-proliferative, pro-apoptotic and anti-cancer activities. Here, we show that NO-sulindac inhibited UVB-induced skin tumorigenesis in SKH-1 hairless mice. Topical application of NO-sulindac reduced tumor incidence, number (psulindac in this study. A reduced expression of PCNA and cyclin D1 associated with the dampening of cell cycle progression was observed. The mechanism of this inhibition was related to the reduction in UVB-induced Notch signaling pathway. UVB-induced inflammatory responses were diminished by NO-sulindac as observed by a remarkable reduction in the levels of phosphorylated MAP Kinases Erk1/2, p38 and JNK1/2. In this regard, NO-sulindac also inhibited NFκB by enhancing IκBα as evidenced by the reduced expression of iNOS and COX-2, the direct NFκB transcription target proteins. NO-sulindac significantly diminished the progression of benign lesions to invasive carcinomas by suppressing the tumor aggressiveness and retarding epithelial-mesenchymal transition. A marked decrease in the expression of mesenchymal markers such as Fibronectin, N-cadherin, SNAI, Slug and Twist and an increase in epithelial cell polarity marker E-cadherin were noted in NO-sulindac-treated tumors. Our data suggest that NO-sulindac is a potent inhibitor of UVB-induced skin carcinogenesis and acts by targeting proliferation-regulatory pathways.

  1. Morinda citrifolia Linn. (Rubiaceae) leaf extracts mitigate UVB-induced erythema.

    Science.gov (United States)

    West, Brett J; Deng, Shixin; Palu, Afa K; Jensen, C Jarakae

    2009-07-01

    Morinda citrifolia Linn. (Rubiaceae) leaves have been used in tropical folk medicine to treat topical inflammation and burns. A carbomer gel base, containing the ethanol extract and juice pressed from the leaves, was evaluated for potential allergenic properties in a repeat-insult patch test in 49 volunteers. To investigate the topical photo-protective properties, the combined ethanol extract and leaf juice were evaluated in a UVB-induced erythema model in 25 volunteers. The crude ethanol extract of M. citrifolia leaves was also evaluated in vitro for potential anti-inflammatory activity in a histamine H-1 receptor antagonism assay. There was no evidence of allergenic potential in the repeat-insult patch test. When the combination of ethanol extract and leaf juice was applied, the UVB dose required to induce erythema was almost 3.5 times greater than with untreated skin (P citrifolia leaves inhibited receptor binding by 57%. These results suggest that M. citrifolia leaves are safe for topical use and may be useful in mitigating UVB-induced injury to the skin.

  2. Saponins from Tribulus terrestris L. protect human keratinocytes from UVB-induced damage.

    Science.gov (United States)

    Sisto, Margherita; Lisi, Sabrina; D'Amore, Massimo; De Lucro, Raffaella; Carati, Davide; Castellana, Donatello; La Pesa, Velia; Zuccarello, Vincenzo; Lofrumento, Dario D

    2012-12-05

    Chronic exposure to solar UVB radiation damages skin, increasing the risk to develop cancer. Hence the identification of compounds with a photoprotective efficacy is essential. This study examined the role of saponins derived from Tribulus terrestris L. (TT) on the modulation of apoptosis in normal human keratinocytes (NHEK) exposed to physiological doses of UVB and to evaluate their antitumoral properties. In NHEK, TT saponins attenuate UVB-induced programmed cell death through inhibition of intrinsic apoptotic pathway. In squamous cell carcinomas (SCC) TT saponins do not make the malignant keratinocytes more resistant to UVB and determine an enhanced apoptotic response. The photoprotective effect of TT saponins is tightly correlated to the enhancement of NER genes expression and the block of UVB-mediated NF-κB activation. Collectively, our study shows experimental evidence that TT has a preventive efficacy against UVB-induced carcinogenesis and the molecular knowledge on the mechanisms through which TT saponins regulate cell death suggests great potential for TT to be developed into a new medicine for cancer patients.

  3. Intraperitoneally administered biliverdin protects against UVB-induced skin photo-damage in hairless mice.

    Science.gov (United States)

    Bai, Bingxue; Liu, Yingdi; You, Yan; Li, Yuzhen; Ma, Liangjuan

    2015-03-01

    Oxidative stress is shown to be responsible for ultraviolet B (UVB) irradiation-induced skin cancer and premature aging. Biliverdin (BVD), a product of heme oxygenase-1, has strong anti-oxidant and anti-inflammatory properties. In the present study, we investigated the effects of BVD on UVB-induced skin photo-damage in hairless mice. Mice were divided into three groups: control group, UVB group (only UVB irradiation) and BVD+UVB group (mice were intraperitoneally injected with BVD before each UVB irradiation). Intraperitoneal BVD injection resulted in a significant photoprotective effect by reducing morphological and histopathological changes to the skin. BVD also exhibited a significant antioxidant effect by increasing the superoxide dismutase (SOD) level and decreasing the thiobarbituric acid reactive substances (TBARS) level compared with the control group. In addition, BVD activated biliverdin reductase (BVR) expression and inhibited the UVB-induced increase of p38 mitogen-activated protein kinase phosphorylation (p-p38MAPK), MMP (matrix metalloproteinase)-1 and MMP-3 expression (pskin photo-damage in hairless mice and that this is likely mediated by its antioxidant and anti-inflammatory mechanisms and cell signal regulatory action.

  4. (Z-5-(2,4-Dihydroxybenzylidenethiazolidine-2,4-dione Prevents UVB-Induced Melanogenesis and Wrinkle Formation through Suppressing Oxidative Stress in HRM-2 Hairless Mice

    Directory of Open Access Journals (Sweden)

    Bonggi Lee

    2016-01-01

    Full Text Available Background. Uncontrolled melanogenesis and wrinkle formation are an indication of photoaging. Our previous studies demonstrated that (Z-5-(2,4-dihydroxybenzylidenethiazolidine-2,4-dione (MHY498 inhibited tyrosinase activity and melanogenesis in vitro. Objective. To examine in vivo effects of MHY498 as an antiaging compound on UVB-induced melanogenesis and wrinkle formation, we topically applied MHY498 on dorsal skin of HRM-2 hairless mice. Methods. Using histological analysis, we evaluated effects of MHY498 on melanogenesis and wrinkle formation after UVB exposure. In addition, related molecular signaling pathways were examined using western blotting, fluorometric assay, and enzyme-linked immunosorbent assay. Results. MHY498 suppressed UVB-induced melanogenesis by inhibiting phosphorylation of CREB and translocation of MITF protein into the nucleus, which are key factors for tyrosinase expression. Consistently, tyrosinase protein levels were notably reduced in the dorsal skin of the hairless mice by MHY498 treatment. Furthermore, MHY498 inhibited UVB-induced wrinkle formation and collagen fiber destruction by increasing type 1 procollagen concentration and decreasing protein expression levels of MMPs, which play an essential role in collagen fiber degradation. As a mechanism, MHY498 notably ameliorated UVB-induced oxidative stress and NF-κB activation in the dermal skin of the hairless mice. Conclusion. Our study suggests that MHY498 can be used as a therapeutic or cosmetic agent for preventing uncontrolled melanogenesis and wrinkle formation.

  5. Nitric oxide-releasing sulindac is a novel skin cancer chemopreventive agent for UVB-induced photocarcinogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Chaudhary, Sandeep C.; Singh, Tripti; Kapur, Puneet; Weng, Zhiping; Arumugam, Aadithya; Elmets, Craig A. [Department of Dermatology, University of Alabama at Birmingham, 1530 3rd Avenue South, VH509, Birmingham, AL 35294-0019 (United States); Kopelovich, Levy [Division of Cancer Prevention, National Cancer Institute, 6130 Executive Blvd, Suite 2114, Bethesda, MD 20892 (United States); Athar, Mohammad, E-mail: mathar@uab.edu [Department of Dermatology, University of Alabama at Birmingham, 1530 3rd Avenue South, VH509, Birmingham, AL 35294-0019 (United States)

    2013-05-01

    Nitric oxide (NO)-releasing non-steroidal anti-inflammatory drugs (NO-NSAIDs) which have been synthesized to reduce gastro-intestinal and cardiovascular toxicities of NSAIDs, possess anti-proliferative, pro-apoptotic and anti-cancer activities. Here, we show that NO-sulindac inhibited UVB-induced skin tumorigenesis in SKH-1 hairless mice. Topical application of NO-sulindac reduced tumor incidence, number (p < 0.05) and volume (p < 0.005) as compared to UVB (alone)-irradiated vehicle-treated mice. An increase in TUNEL-positive cells in skin lesions was accompanied by the enhanced Bax:Bcl-2 ratio. The expression of pro-apoptotic Bax was increased whereas anti-apoptotic Bcl-2 reduced. However, proliferation was identified as the major target of NO-sulindac in this study. A reduced expression of PCNA and cyclin D1 associated with the dampening of cell cycle progression was observed. The mechanism of this inhibition was related to the reduction in UVB-induced Notch signaling pathway. UVB-induced inflammatory responses were diminished by NO-sulindac as observed by a remarkable reduction in the levels of phosphorylated MAP Kinases Erk1/2, p38 and JNK1/2. In this regard, NO-sulindac also inhibited NFκB by enhancing IκBα as evidenced by the reduced expression of iNOS and COX-2, the direct NFκB transcription target proteins. NO-sulindac significantly diminished the progression of benign lesions to invasive carcinomas by suppressing the tumor aggressiveness and retarding epithelial–mesenchymal transition. A marked decrease in the expression of mesenchymal markers such as Fibronectin, N-cadherin, SNAI, Slug and Twist and an increase in epithelial cell polarity marker E-cadherin were noted in NO-sulindac-treated tumors. Our data suggest that NO-sulindac is a potent inhibitor of UVB-induced skin carcinogenesis and acts by targeting proliferation-regulatory pathways. - Highlights: ► NO-sulindac is a potent chemopreventive agent for UVB-induced skin cancer. ► NO

  6. Human papillomavirus types detected in skin warts and cancer differ in their transforming properties but commonly counteract UVB induced protective responses in human keratinocytes

    Energy Technology Data Exchange (ETDEWEB)

    Shterzer, Naama; Heyman, Dariya; Shapiro, Beny; Yaniv, Abraham; Jackman, Anna [Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel-Aviv University, Tel-Aviv (Israel); Serour, Francis [Department of Pediatric Surgery, The E. Wolfson Medical Center, Holon (Israel); Chaouat, Malka [Laboratory of Experimental Surgery, Hadassah University Hospital, Ein Karem, Jerusalem (Israel); Gonen, Pinhas [Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel-Aviv University, Tel-Aviv (Israel); Tommasino, Massimo [International Agency for Research on Cancer, World Health Organization, Lyon (France); Sherman, Levana [Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel-Aviv University, Tel-Aviv (Israel)

    2014-11-15

    In the present study, E6E7 and E6 proteins of human papillomaviruses (HPVs) associated with skin warts and cancer were compared for their transforming and carcinogenic abilities in primary human keratinocytes (PHKs). We show that E6E7 of cancer associated beta HPV types, notably 49 and 24, were able to extend the life span and enhance the clonogenic efficiency of PHKs when maintained in serum free/low calcium medium. Activities of the beta HPV E6E7 were lower than those of HPV16 E6E7. In contrast, E6 proteins from HPV types detected in skin warts or cancer, notably 10, 49 and 38, attenuated UVB induced protective responses in PHKs including cell death, proliferation arrest and accumulation of the proapoptotic proteins, p53, bax or bak. Together, this investigation revealed functional differences and commonalities between HPVs associated with skin warts and cancer, and allowed the identification of specific properties of beta HPVs supporting their involvement in skin carcinogenesis. - Highlights: • Primary keratinocytes were used to evaluate transforming and carcinogenic abilities of cutaneous HPVs. • E6E7 of cancer associated β HPV types transform primary human keratinocytes. • E6 proteins of cancer and wart associated HPVs inhibit UVB induced cell death. • E6s of cancer and wart associated HPVs attenuate UVB induced proliferation arrest. • E6s of cancer and wart associated HPVs attenuate UVB induced apoptosis signaling.

  7. Chrysin protects epidermal keratinocytes from UVA- and UVB-induced damage.

    Science.gov (United States)

    Wu, Nan-Lin; Fang, Jia-You; Chen, Marcelo; Wu, Chia-Jung; Huang, Chieh-Chen; Hung, Chi-Feng

    2011-08-10

    Chrysin (5,7-dihydroxyflavone), a natural flavonoid occurring in various plants and foods such as propolis and honey, reportedly opposes inflammation and carcinogenesis, but has rarely been applied in skin care. This study, therefore, aimed to explore the roles of chrysin in protection against UV-induced damage in HaCaT keratinocytes. Results showed that chrysin can attenuate apoptosis, reactive oxygen species (ROS) production, and cyclooxygenase 2 (COX-2) expression induced by UVB and UVA. Chrysin predominantly reversed the down-regulation of aquaporin 3 (AQP-3) by UVB. It predominantly reversed JNK activation and also mildly inhibited p38 activation triggered by UVA and UVB. Animal studies revealed that chrysin's topical application demonstrated efficient percutaneous absorption and no skin irritation. Overall, results demonstrated significant benefits of chrysin on the protection of keratinocytes against UVA- and UVB-induced injuries and suggested its potential use in skin photoprotection.

  8. Ultra-violet B (UVB)-induced skin cell death occurs through a cyclophilin D intrinsic signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Chao [Department of Dermatology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210024, Jiangsu (China); Yang, Bo [Department of Dermatology, Huashan Hospital, Fudan University, Shanghai 200040 (China); Yang, Zhi; Tu, Ying [Department of Dermatology, The First Affiliated Hospital of Kunming Medical University, Yunnan Provincial Institute of Dermatology, Kunming 650032, Yunnan (China); Yang, Yan-li [Department of Otorhinolaryngology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210024, Jiangsu (China); He, Li, E-mail: heli2662@yahoo.com.cn [Department of Otorhinolaryngology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210024, Jiangsu (China); Bi, Zhi-Gang, E-mail: eltonbibenqhospital@yahoo.com.cn [Department of Dermatology, BenQ Medical Center, Nanjing Medical University, Nanjing 210019, Jiangsu (China)

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer UVB radiated skin keratinocytes show cyclophilin D (Cyp-D) upregulation. Black-Right-Pointing-Pointer NAC inhibits UVB induced Cyp-D expression, while H{sub 2}O{sub 2} facilitates it. Black-Right-Pointing-Pointer Cyp-D-deficient cells are significantly less susceptible to UVB induced cell death. Black-Right-Pointing-Pointer Over-expression of Cyp-D causes spontaneous keratinocytes cell death. -- Abstract: UVB-induced skin cell damage involves the opening of mitochondrial permeability transition pore (mPTP), which leads to both apoptotic and necrotic cell death. Cyclophilin D (Cyp-D) translocation to the inner membrane of mitochondrion acts as a key component to open the mPTP. Our Western-Blot results in primary cultured human skin keratinocytes and in HaCaT cell line demonstrated that UVB radiation and hydrogen peroxide (H{sub 2}O{sub 2}) induced Cyp-D expression, which was inhibited by anti-oxidant N-acetyl cysteine (NAC). We created a stable Cyp-D deficiency skin keratinocytes by expressing Cyp-D-shRNA through lentiviral infection. Cyp-D-deficient cells were significantly less susceptible than their counterparts to UVB- or H{sub 2}O{sub 2}-induced cell death. Further, cyclosporine A (Cs-A), a Cyp-D inhibitor, inhibited UVB- or H{sub 2}O{sub 2}-induced keratinocytes cell death. Reversely, over-expression of Cyp-D in primary keratinocytes caused spontaneous keratinocytes cell death. These results suggest Cyp-D's critical role in UVB/oxidative stress-induced skin cell death.

  9. Synthesis of lipid mediators during UVB-induced inflammatory hyperalgesia in rats and mice.

    Directory of Open Access Journals (Sweden)

    Marco Sisignano

    Full Text Available Peripheral sensitization during inflammatory pain is mediated by a variety of endogenous proalgesic mediators including a number of oxidized lipids, some of which serve endogenous modulators of sensory TRP-channels. These lipids are eicosanoids of the arachidonic acid and linoleic acid pathway, as well as lysophophatidic acids (LPAs. However, their regulation pattern during inflammatory pain and their contribution to peripheral sensitization is still unclear. Here, we used the UVB-model for inflammatory pain to investigate alterations of lipid concentrations at the site of inflammation, the dorsal root ganglia (DRGs as well as the spinal dorsal horn and quantified 21 lipid species from five different lipid families at the peak of inflammation 48 hours post irradiation. We found that known proinflammatory lipids as well as lipids with unknown roles in inflammatory pain to be strongly increased in the skin, whereas surprisingly little changes of lipid levels were seen in DRGs or the dorsal horn. Importantly, although there are profound differences between the number of cytochrome (CYP genes between mice and rats, CYP-derived lipids were regulated similarly in both species. Since TRPV1 agonists such as LPA 18∶1, 9- and 13-HODE, 5- and 12-HETE were elevated in the skin, they may contribute to thermal hyperalgesia and mechanical allodynia during UVB-induced inflammatory pain. These results may explain why some studies show relatively weak analgesic effects of cyclooxygenase inhibitors in UVB-induced skin inflammation, as they do not inhibit synthesis of other proalgesic lipids such as LPA 18∶1, 9-and 13-HODE and HETEs.

  10. Cordycepin-Enriched WIB801C from Cordyceps militaris Inhibits Collagen-Induced [Ca2+]i Mobilization via cAMP-Dependent Phosphorylation of Inositol 1, 4, 5-Trisphosphate Receptor in Human Platelets

    Science.gov (United States)

    Lee, Dong-Ha; Kim, Hyun-Hong; Cho, Hyun-Jeong; Yu, Young-Bin; Kang, Hyo-Chan; Kim, Jong-Lae; Lee, Jong-Jin; Park, Hwa-Jin

    2014-01-01

    In this study, we prepared cordycepin-enriched (CE)-WIB801C, a n-butanol extract of Cordyceps militaris-hypha, and investigated the effect of CE-WIB801C on collagen-induced human platelet aggregation. CE-WIB801C dose-dependently inhibited collagen-induced platelet aggregation, and its IC50 value was 175 μg/ml. CE-WIB801C increased cAMP level more than cGMP level, but inhibited collagen-elevated [Ca2+]i mobilization and thromboxane A2 (TXA2) production. cAMP-dependent protein kinase (A-kinase) inhibitor Rp-8-Br-cAMPS increased the CE-WIB801C-downregulated [Ca2+]i level in a dose dependent manner, and strongly inhibited CE-WIB801C-induced inositol 1, 4, 5-trisphosphate receptor (IP3R) phosphorylation. These results suggest that the inhibition of [Ca2+]i mobilization by CE-WIB801C is resulted from the cAMP/A-kinase-dependent phosphorylation of IP3R. CE-WIB801C suppressed TXA2 production, but did not inhibit the activities of cyclooxygenase-1 (COX-1) and TXA2 synthase (TXAS). These results suggest that the inhibition of TXA2 production by WIB801C is not resulted from the direct inhibition of COX-1 and TXAS. In this study, we demonstrate that CE-WIB801C with cAMP-dependent Ca2+-antagonistic antiplatelet effects may have preventive or therapeutic potential for platelet aggregation-mediated diseases, such as thrombosis, myocardial infarction, atherosclerosis, and ischemic cerebrovascular disease. PMID:25009703

  11. MAPKs and Mst1/Caspase-3 pathways contribute to H2B phosphorylation during UVB-induced apoptosis

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Apoptosis is a highly coordinated or programmed cell suicide mechanism in eukaryotes.Histone modification is associated with nuclear events in apoptotic cells.Specifically H2B phosphorylation at serine 14 (Ser14) catalyzed by Mst1 kinase has been linked to chromatin condensation during apoptosis.We report that activation of MAPKs (ERK1/2,JNK1/2 and p38) together with Mst1 and caspase-3 is required for phosphorylation of H2B (Ser14) during ultraviolet B light (UVB)-induced apoptosis.UVB can trigger activation of MAPKs and induce H2B phosphorylation at Ser14 but not acetylation in a time-dependent manner.Inhibition of ERK1/2,JNK1/2 or p38 activity blocked H2B phosphorylation (Ser14).Furthermore,caspase-3 was activated by UVB to regulate Mst1 activity,which phosphorylates H2B at Ser14,leading to chromatin condensation.Full inhibition of caspase-3 activity reduced Mst1 activation and partially inhibited H2B phosphorylation (Ser14),but ERK1/2,JNK1/2 and p38 activities were not affected.Taken together,these data revealed that H2B phosphorylation is regulated by both MAPKs and caspase-3/Mst1 pathways during UVB-induced apoptosis.

  12. Effect of inositol hexaphosphate on the development of UVB-induced skin tumors in SKH1 hairless mice.

    Science.gov (United States)

    Kolappaswamy, Krishnan; Williams, Kendra A; Benazzi, Cinzia; Sarli, Giuseppe; McLeod, Charles G; Vucenik, Ivana; DeTolla, Louis J

    2009-04-01

    Inositol hexaphosphate (IP6) is a naturally occurring polyphosphorylated carbohydrate that is abundant in many plants and in various high-fiber foods, such as cereals and legumes. IP6 has a striking, broad-spectrum anticancer activity in various in vitro and animal models, in which it interferes with key pathways in malignancy to inhibit cell proliferation, cell-cycle progression, metastasis, invasion, and angiogenesis and to induce apoptosis. In this study, we investigated the protective effects of IP6 in drinking water on the incidence of UVB-induced skin cancer in the SKH1 (Crl: SKH1-hr) mouse model. One group of 15 mice received 2% IP6 in drinking water and UVB exposure, and the other group (n = 15) received UVB exposure only. All mice in both groups were fed an IP6-deficient diet (AIN 76A). The treatment group started receiving 2% IP6 in the drinking water 3 d before irradiation. Mice were irradiated 3 times each week, starting at a dose of 1.5 kJ/m2, with weekly increases in increments of 1.5 kJ/m2 to a final dose of 7.5 kJ/m2. Tumor formation was monitored until the week 31. IP6 in drinking water significantly decreased tumor incidence by 5-fold and tumor multiplicity by 4-fold. These results show that IP6 has an antiphotocarcinogenic effect and can protect against UVB-induced tumor formation.

  13. Passiflora tarminiana fruits reduce UVB-induced photoaging in human skin fibroblasts.

    Science.gov (United States)

    Bravo, Karent; Duque, Luisa; Ferreres, Federico; Moreno, Diego A; Osorio, Edison

    2017-03-01

    Skin aging is a complex process that is strongly affected by UV radiation, which stimulates the production of reactive oxygen species (ROS) in the epidermis and dermis and subsequently causes skin damage. Among the major consequences are increased collagen degradation and reduced collagen synthesis. Previous reports have demonstrated the beneficial effects of polyphenols for healthy skin. Passiflora tarminiana Coppens & V.E. Barney, a species of the Passifloraceae family, is widely distributed in South America and is rich in flavonoids. We show that UVB radiation increases metalloproteinase 1 (MMP-1) and reduces procollagen production in human dermal fibroblast (HDF) cells in a dose- and time-dependent manner. We examined the antioxidant and antiaging effects of the extract and fractions of P. tarminiana fruits. The fractions showed high polyphenol content (620mg EAG/g) and antioxidant activity, as measured by ORAC (4097μmol ET/g) and ABTS (2992μmol ET/g) assays. The aqueous fraction drastically inhibited the collagenase enzyme (IC50 0.43μg/mL). The extract and fractions presented photoprotective effects by reducing UVB-induced MMP-1 production, increasing UVB-inhibited procollagen production, and decreasing ROS production after UVB irradiation in HDF. Finally, the polyphenol contents of the extracts and fractions from P. tarminiana were analyzed by HPLC-DAD-ESI-MS(n), and procyanidins and glycosylated flavonoids were identified. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Cordycepin analogs of 2-5A: activity in rabbit reticulocyte lysates and extracts from L929 cells

    Energy Technology Data Exchange (ETDEWEB)

    Suhadolnik, R.J.; Kariko, K.; Reichenbach, N.L.; Wu, J.M.

    1986-05-01

    Enzymatically and chemically synthesized cordycepin trimer and tetramer analogs of 2-5A (i) inhibit protein synthesis in rabbit reticulocyte lysates (RRL) and intact L929 cells and (ii) bind to and activate partially purified RNase L from RRL to degrade viral mRNA. Direct evidence is presented here that the cordycepin analogs act via activation of RNase L. First, 2-5A and cordycepin tetramer triphosphates (3 x 10/sup -8/ M) degrade mRNA in RRL 55% and 59%, respectively. Second, 2-5A and cordycepin trimer and tetramer triphosphates (5 x 10/sup -9/ M) prevent covalent binding of periodate oxidized p/sub 3/A/sub 4/(/sup 32/P)pC to RNase L from RRL. Third, in incubations of L929 cell extracts, 2-5A and cordycepin trimer and tetramer triphosphates (1 x 10/sup -9/ M) activate RNase L to degrade 18S and 28S rRNA to specific cleavage products. When the same L929 RNase L is bound to 2-5A core cellulose, the RNase L can be activated by 2-5A, but not by cordycepin tetramer triphosphate, to degrade polyU. These data show that the 3'-hydroxyls of 2-5A are not an obligatory requirements for activation of RNase L and subsequent degradation of natural RNAs, but appear to be critical for the enzymatic degradation of a synthetic polyribonucleotide such as polyU.

  15. Interference of silibinin with IGF-1R signalling pathways protects human epidermoid carcinoma A431 cells from UVB-induced apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Weiwei; Otkur, Wuxiyar; Li, Lingzhi; Wang, Qiong; He, Hao; Zang, Linghe; Hayashi, Toshihiko [China–Japan Research Institute of Medical and Pharmaceutical Sciences, Shenyang Pharmaceutical University, Shenyang 110016 (China); Tashiro, Shin-ichi [Institute for Clinical and Biomedical Sciences, Kyoto 603-8072 (Japan); Onodera, Satoshi [Department of Clinical and Biomedical Sciences, Showa Pharmaceutical University, Tokyo 194-8543 (Japan); Xia, Mingyu [China–Japan Research Institute of Medical and Pharmaceutical Sciences, Shenyang Pharmaceutical University, Shenyang 110016 (China); Ikejima, Takashi, E-mail: ikejimat@vip.sina.com [China–Japan Research Institute of Medical and Pharmaceutical Sciences, Shenyang Pharmaceutical University, Shenyang 110016 (China)

    2013-03-08

    Highlights: ► Silibinin protects A431 cells from UVB irradiation-induced apoptosis. ► Up-regulation of the IGF-1R-JNK/ERK pathways by UVB induces cell apoptosis. ► Silibinin inhibits IGF-1R pathways to repress caspase-8-mediated apoptosis. -- Abstract: Ultraviolet B (UVB) from sunlight is a major cause of cutaneous lesion. Silibinin, a traditional hepatic protectant, elicits protective effects against UVB-induced cellular damage. In A431 cells, the insulin-like growth factor-1 receptor (IGF-1R) was markedly up-regulated by UVB irradiation. The activation of the IGF-1R signalling pathways contributed to apoptosis of the cells rather than rescuing the cells from death. Up-regulated IGF-1R stimulated downstream mitogen-activated protein kinases (MAPKs), such as c-Jun N-terminal kinases (JNK) and extracellular signal-regulated protein kinases 1/2 (ERK1/2). The subsequent activation of caspase-8 and caspase-3 led to apoptosis. The activation of IGF-1R signalling pathways is the cause of A431 cell death. The pharmacological inhibitors and the small interfering RNA (siRNA) targeting IGF-1R suppressed the downstream activation of JNK/ERK-caspases to help the survival of the UVB-irradiated A431 cells. Indeed, silibinin treatment suppressed the IGF-1R-JNK/ERK pathways and thus protected the cells from UVB-induced apoptosis.

  16. Preliminary Study on Cordycepin-DNA Interaction by Raman Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    Jian Ya LING; Qin Zheng YANG; Shan Shan LUO; Yan LI; Chang Kai ZHANG

    2005-01-01

    The interaction of cordycepin with calf thymus DNA was investigated at physiological pH with drug/DNA molar ratio of 8. The Raman spectroscopy results indicated that the intercalation of high concentration cordycepin and the interaction of cordycepin with PO2 group led to a major reduction of B-form DNA structure in favor of A-form DNA.

  17. Protective effect of mango (Mangifera indica L.) against UVB-induced skin aging in hairless mice.

    Science.gov (United States)

    Song, Jae Hyoung; Bae, Eun Young; Choi, Goya; Hyun, Jin Won; Lee, Mi Young; Lee, Hye Won; Chae, Sungwook

    2013-04-01

    Mangifera indica L. (Anacardiaceae) is a medicinal plant whose extracts have been described as an antioxidant with anti-inflammatory and immunomodulatory activities. Skin aging is a consequence of chronic sun exposure to the sun and therefore ultraviolet (UV) radiation. Naturally occurring antioxidants are known to reduce skin aging. Therefore, the aim of the present study was to evaluate the protective role of mango extract against UVB-induced skin aging in hairless mice. HR-1 hairless male mice (6 weeks old) were divided into three groups: control (n = 5), UVB-treated vehicle (n = 5), and UVB-treated mango extract (n = 5) groups. UVB-irradiated mice from the mango extract group were orally administered 0.1 ml of water containing 100 mg of mango extract/kg body weight per day. The inhibitory activity of mango extract on wrinkle formation was determined by the analysis of the skin replica, epidermal thickness based on histological examination, and damage to collagen fiber. The mean length of wrinkles in UVB-treated vehicle group significantly improved after the oral administration of mango extract, which significantly inhibited the increase in epidermal thickness and epidermal hypertrophy (P mango extract by Masson's trichrome staining. These results indicate that mango extract showed anti-photoaging activity in UVB-irradiated hairless mice. © 2013 John Wiley & Sons A/S.

  18. Adiponectin Suppresses UVB-Induced Premature Senescence and hBD2 Overexpression in Human Keratinocytes.

    Science.gov (United States)

    Kim, MinJeong; Park, Kui Young; Lee, Mi-Kyung; Jin, Taewon; Seo, Seong Jun

    2016-01-01

    Recent studies have revealed that adiponectin can suppress cellular inflammatory signaling pathways. This study aimed to elucidate the effect of adiponectin on the unregulated production of hBD2 in UVB-induced premature senescent keratinocytes. We constructed an in vitro model of premature senescent keratinocytes through repeated exposure to low energy UVB. After repeated low energy UVB exposure, there was significant generation of reactive oxygen species (ROS) and induction of senescence-associated markers, including senescence associated beta-galactosidase activity and expression of p16INK4a and histone H2AX. In addition, the present clinical study showed higher expression of hBD2 in sun-exposed skin of elderly group, and the overexpression of hBD2 was observed by c-Fos activation in vitro. Adiponectin has the ability to scavenge ROS and consequently inhibit MAPKs and SA-markers in UVB-exposed keratinocytes. An inhibitor study demonstrated that adiponectin downregulated hBD2 mRNA expression through suppression of the AP-1 transcription factor components c-Fos via inactivation of p38 MAPK. Collectively, the dysregulated production of hBD2 by the induction of oxidative stress was attenuated by adiponectin through the suppression of p38 and JNK/SAPK MAPK signaling in UVB-mediated premature senescent inducible conditions. These results suggest the feasibility of adiponectin as an anti-photoaging and anti-inflammatory agent in the skin.

  19. Anticancer and antimetastatic effects of cordycepin, an active component of Cordyceps sinensis

    Directory of Open Access Journals (Sweden)

    Kazuki Nakamura

    2015-01-01

    Full Text Available Cordyceps sinensis, a fungus that parasitizes on the larva of Lepidoptera, has been used as a valued traditional Chinese medicine. We investigated the effects of water extracts of Cordyceps sinensis (WECS, and particularly focused on its anticancer and antimetastatic actions. Based on in vitro studies, we report that WECS showed an anticancer action, and this action was antagonized by an adenosine A3 receptor antagonist. Moreover, this anticancer action of WECS was promoted by an adenosine deaminase inhibitor. These results suggest that one of the components of WECS with an anticancer action might be an adenosine or its derivatives. Therefore, we focused on cordycepin (3′-deoxyadenosine as one of the active ingredients of WECS. According to our experiments, cordycepin showed an anticancer effect through the stimulation of adenosine A3 receptor, followed by glycogen synthase kinase (GSK-3β activation and cyclin D1 suppression. Cordycepin also showed an antimetastatic action through inhibiting platelet aggregation induced by cancer cells and suppressing the invasiveness of cancer cells via inhibiting the activity of matrix metalloproteinase (MMP-2 and MMP-9, and accelerating the secretion of tissue inhibitor of metalloproteinase (TIMP-1 and TIMP-2 from cancer cells. In conclusion, cordycepin, an active component of WECS, might be a candidate anticancer and antimetastatic agent.

  20. Cordycepin Down-Regulates Multiple Drug Resistant (MDR/HIF-1α through Regulating AMPK/mTORC1 Signaling in GBC-SD Gallbladder Cancer Cells

    Directory of Open Access Journals (Sweden)

    Wei-Ding Wu

    2014-07-01

    Full Text Available Gallbladder cancer is the most common malignancy of the bile duct, with low 5-year survival rate and poor prognosis. Novel effective treatments are urgently needed for the therapy of this disease. Here, we showed that cordycepin, the bioactive compound in genus Cordyceps, induced growth inhibition and apoptosis in cultured gallbladder cancer cells (Mz-ChA-1, QBC939 and GBC-SD lines. We found that cordycepin inhibited mTOR complex 1 (mTORC1 activation and down-regulated multiple drug resistant (MDR/hypoxia-inducible factor 1α (HIF-1α expression through activating of AMP-activated protein kinase (AMPK signaling in gallbladder cancer GBC-SD cells. Contrarily, AMPKα1-shRNA depletion dramatically inhibited cordycepin-induced molecular changes as well as GBC-SD cell apoptosis. Further, our results showed that co-treatment with a low concentration cordycepin could remarkably enhance the chemosensitivity of GBC-SD cells to gemcitabine and 5-fluorouracil (5-FU, and the mechanism may be attributed to AMPK activation and MDR degradation. In summary, cordycepin induces growth inhibition and apoptosis in gallbladder cancer cells via activating AMPK signaling. Cordycepin could be a promising new drug or chemo-adjuvant for gallbladder cancer.

  1. MLK3 is a novel target of dehydroglyasperin D for the reduction in UVB-induced COX-2 expression in vitro and in vivo.

    Science.gov (United States)

    Jung, Sung Keun; Ha, Su Jeong; Kim, Yeong A; Lee, Jihoon; Lim, Tae-Gyu; Kim, Yun Tai; Lee, Nam Hyouck; Park, Jun Seong; Yeom, Myeong-Hun; Lee, Hyong Joo; Lee, Ki Won

    2015-01-01

    Dehydroglyasperin D (DHGA-D), a compound present in licorice, has been found to exhibit anti-obesity, antioxidant and anti-aldose reductase effects. However, the direct molecular mechanism and molecular targets of DHGA-D during skin inflammation remain unknown. In the present study, we investigated the effect of DHGA-D on inflammation and its mechanism of action on UVB-induced skin inflammation in HaCaT human keratinocytes and SKH-1 hairless mice. DHGA-D treatment strongly suppressed UVB-induced COX-2 expression, PGE2 generation and AP-1 transactivity in HaCaT cells without affecting cell viability. DHGA-D also inhibited phosphorylation of the mitogen-activated protein kinase kinase (MKK) 3/6/p38, MAPK/Elk-1, MKK4/c-Jun N-terminal kinase (JNK) 1/2/c-Jun/mitogen, and stress-activated protein kinase (MSK), whereas phosphorylation of the mixed-lineage kinase (MLK) 3 remained unaffected. Kinase and co-precipitation assays with DHGA-D Sepharose 4B beads showed that DHGA-D significantly suppressed MLK3 activity through direct binding to MLK3. Knockdown of MLK3 suppressed COX-2 expression as well as phosphorylation of MKK4/p38 and MKK3/6/JNK1/2 in HaCaT cells. Furthermore, Western blot assay and immunohistochemistry results showed that DHGA-D pre-treatment significantly inhibits UVB-induced COX-2 expression in vivo. Taken together, these results indicate that DHGA-D may be a promising anti-inflammatory agent that mediates suppression of both COX-2 expression and the MLK3 signalling pathway through direct binding and inhibition of MLK3.

  2. Recall of UVB-induced erythema in breast cancer patient receiving multiple drug chemotherapy

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Lindskov, R

    1984-01-01

    One day after sunbathing, a breast cancer patient received intravenous methotrexate, cyclophosphamide and 5-fluorouracil and had a recall of her UV erythema over the following week. Phototesting with UVA and UVB prior to and after a subsequent chemotherapy treatment showed a UVB-induced recall of...

  3. Long-wave UVA offers partial protection against UVB-induced

    DEFF Research Database (Denmark)

    Skov, L.; Villadsen, L.; Ersbøll, Bjarne Kjær

    2000-01-01

    Ultraviolet-B (UVB, 280–320 nm) interferes with the generation of cell-mediated immunity to contact allergens applied epicutaneously on the irradiated site. To investigate whether pretreatment with UVA-1 (340–400 nm) protects against the UVB-induced immune suppression we sensitized human volunteers...

  4. Chemopreventive effects of Calluna vulgaris and Vitis vinifera extracts on UVB-induced skin damage in SKH-1 hairless mice.

    Science.gov (United States)

    Filip, A; Clichici, S; Daicoviciu, D; Catoi, C; Bolfa, P; Postescu, I D; Gal, A; Baldea, I; Gherman, C; Muresan, A

    2011-06-01

    Solar ultraviolet radiation (UV) is a major cause of non-melanoma skin cancer in humans. Photochemoprevention with natural products represents a simple but very effective strategy in the management of cutaneous neoplasia. The study investigated the protective activity of Calluna vulgaris (Cv) and red grape seeds (Vitis vinifera L, Burgund Mare variety) (BM) extracts in vivo on UVB-induced deleterious effects in SKH-1 mice skin. Forty SKH-1 mice were randomly divided into 4 groups (n=10): control, UVB irradiated, Cv + UVB irradiated, BM+UVB irradiated. Both extracts were applied topically on the skin in a dose of 4 mg/40 μl/cm(2) before UVB exposure - single dose. The effects were evaluated in skin 24 hours after irradiation through the presence of cyclobutane pyrimidine dimers (CPDs) and sunburn cells, tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6 levels. The antioxidant activity of BM extract was higher than those of Cv extract as determined using stable free radical DPPH assay and ABTS test. One single dose of UVB generated formation of CPDs (p<0.0001) and sunburn cells (p<0.0002) and increased the cytokine levels in skin (p<0.0001). Twenty hours following irradiation BM extract inhibited UVB-induced sunburn cells (p<0.02) and CPDs formation (p<0.0001). Pretreatment with Cv and BM extracts resulted in significantly reduced levels of IL-6 and TNF-α compared with UVB alone (p<0.0001). Our results suggest that BM extracts might be a potential candidate in preventing the damages induced by UV in skin.

  5. Fisetin Regulates Nrf2 Expression and the Inflammation-Related Signaling Pathway to Prevent UVB-Induced Skin Damage in Hairless Mice

    Directory of Open Access Journals (Sweden)

    Po-Yuan Wu

    2017-10-01

    Full Text Available Chronic ultraviolet (UV exposure may cause skin damage, disrupt skin barrier function, and promote wrinkle formation. UV induces oxidative stress and inflammation, which results in extracellular matrix degradation in the dermis and epidermal hyperplasia. Our previous study demonstrated that fisetin exerts photoprotective activity by inhibiting mitogen-activated protein kinase/activator protein-1/matrix metalloproteinases (MMPs activation. In this study, fisetin was applied topically to investigate its antiphotodamage effects in hairless mice. The erythema index (a* values and transepidermal water loss were evaluated to assess skin damage, and immunohistochemical staining was conducted to elucidate the photoprotective mechanism of fisetin. The results revealed that the topical application of fisetin reduced UVB-induced increase in the a* value and wrinkle formation. In addition, fisetin inhibited epidermal hyperplasia and increased the collagen content in the dermis. Fisetin exerted photoprotective activity by inhibiting the expression of MMP-1, MMP-2, and cyclooxygenase-2 and increasing the expression of nuclear factor erythroid 2-related factor. Furthermore, fisetin increased the expression of filaggrin to prevent UVB-induced barrier function disruption. Altogether, the present results provide evidence of the effects and mechanisms of fisetin’s antiphotodamage and antiphotoinflammation activities.

  6. Fisetin Regulates Nrf2 Expression and the Inflammation-Related Signaling Pathway to Prevent UVB-Induced Skin Damage in Hairless Mice.

    Science.gov (United States)

    Wu, Po-Yuan; Lyu, Jia-Ling; Liu, Yi-Jung; Chien, Ting-Yi; Hsu, Hao-Cheng; Wen, Kuo-Ching; Chiang, Hsiu-Mei

    2017-10-10

    Chronic ultraviolet (UV) exposure may cause skin damage, disrupt skin barrier function, and promote wrinkle formation. UV induces oxidative stress and inflammation, which results in extracellular matrix degradation in the dermis and epidermal hyperplasia. Our previous study demonstrated that fisetin exerts photoprotective activity by inhibiting mitogen-activated protein kinase/activator protein-1/matrix metalloproteinases (MMPs) activation. In this study, fisetin was applied topically to investigate its antiphotodamage effects in hairless mice. The erythema index (a* values) and transepidermal water loss were evaluated to assess skin damage, and immunohistochemical staining was conducted to elucidate the photoprotective mechanism of fisetin. The results revealed that the topical application of fisetin reduced UVB-induced increase in the a* value and wrinkle formation. In addition, fisetin inhibited epidermal hyperplasia and increased the collagen content in the dermis. Fisetin exerted photoprotective activity by inhibiting the expression of MMP-1, MMP-2, and cyclooxygenase-2 and increasing the expression of nuclear factor erythroid 2-related factor. Furthermore, fisetin increased the expression of filaggrin to prevent UVB-induced barrier function disruption. Altogether, the present results provide evidence of the effects and mechanisms of fisetin's antiphotodamage and antiphotoinflammation activities.

  7. Protective effect of trehalose-loaded liposomes against UVB-induced photodamage in human keratinocytes

    Science.gov (United States)

    EMANUELE, ENZO; BERTONA, MARCO; SANCHIS-GOMAR, FABIAN; PAREJA-GALEANO, HELIOS; LUCIA, ALEJANDRO

    2014-01-01

    Trehalose, a naturally occurring non-reducing disaccharide, is known to act as a major protein stabilizer that can reduce ultraviolet B (UVB)-induced corneal damage when topically applied to the eye. However, due to the low skin permeability of trehalose, which makes the development of topical formulations difficult, its use as a skin photoprotective agent has been limited. Previous findings demonstrated that liposomes may significantly improve the intracellular delivery of trehalose. Therefore, the present study aimed to assess the protective effects of trehalose-loaded liposomes against UVB-induced photodamage using the immortalized human keratinocyte cell line, HaCaT. The effects were also compared to those of the common skin photoprotective compounds, including L-carnosine, L-(+)-ergothioneine, L-ascorbic acid and DL-α-tocopherol. The levels of cyclobutane pyrimidine dimers, 8-hydroxy-2′-deoxyguanosine and protein carbonylation in HaCaT cells were used as biological markers of UVB-induced damage. Compared to other compounds, trehalose-loaded liposomes showed the highest efficacy in reducing the levels of the three markers following UVB irradiation of HaCaT cells (all P<0.001 when compared to each of the four other photoprotective compounds). Therefore, these findings indicate that there may be a clinical application for trehalose-loaded liposomes, and further studies should be performed to assess the potential usefulness in skin photoprotection and the prevention of non-melanoma skin cancer. PMID:25054023

  8. Derinat Protects Skin against Ultraviolet-B (UVB-Induced Cellular Damage

    Directory of Open Access Journals (Sweden)

    Wen-Li Hsu

    2015-11-01

    Full Text Available Ultraviolet-B (UVB is one of the most cytotoxic and mutagenic stresses that contribute to skin damage and aging through increasing intracellular Ca2+ and reactive oxygen species (ROS. Derinat (sodium deoxyribonucleate has been utilized as an immunomodulator for the treatment of ROS-associated diseases in clinics. However, the molecular mechanism by which Derinat protects skin cells from UVB-induced damage is poorly understood. Here, we show that Derinat significantly attenuated UVB-induced intracellular ROS production and decreased DNA damage in primary skin cells. Furthermore, Derinat reduced intracellular ROS, cyclooxygenase-2 (COX-2 expression and DNA damage in the skin of the BALB/c-nu mice exposed to UVB for seven days in vivo. Importantly, Derinat blocked the transient receptor potential canonical (TRPC channels (TRPCs, as demonstrated by calcium imaging. Together, our results indicate that Derinat acts as a TRPCs blocker to reduce intracellular ROS production and DNA damage upon UVB irradiation. This mechanism provides a potential new application of Derinat for the protection against UVB-induced skin damage and aging.

  9. Anti-inflammatory effects of cordycepin in lipopolysaccharide-stimulated RAW 264.7 macrophages through Toll-like receptor 4-mediated suppression of mitogen-activated protein kinases and NF-κB signaling pathways

    Directory of Open Access Journals (Sweden)

    Choi YH

    2014-10-01

    Full Text Available Yung Hyun Choi,1,2 Gi-Young Kim,3 Hye Hyeon Lee4 1Department of Biochemistry, Dongeui University College of Korean Medicine, Busan, 2Anti-Aging Research Center and Blue-Bio Industry RIC, Dongeui University, Busan, 3Laboratory of Immunobiology, Department of Marine Life Sciences, Jeju National University, Jeju, 4Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea Abstract: Cordycepin is the main functional component of the Cordyceps species, which has been widely used in traditional Oriental medicine. This compound possesses many pharmacological properties, such as an ability to enhance immune function, as well as antioxidant, antiaging, and anticancer effects. In the present study, we investigated the anti-inflammatory effects of cordycepin using a murine macrophage RAW 264.7 cell model. Our data demonstrated that cordycepin suppressed production of proinflammatory mediators such as nitric oxide (NO and prostaglandin E2 by inhibiting inducible NO synthase and cyclooxygenase-2 gene expression. Cordycepin also inhibited the release of proinflammatory cytokines, including tumor necrosis factor-alpha and interleukin-1-beta, through downregulation of respective mRNA expression. In addition, pretreatment with cordycepin significantly inhibited lipopolysaccharide (LPS-induced phosphorylation of mitogen-activating protein kinases and attenuated nuclear translocation of NF-κB by LPS, which was associated with abrogation of inhibitor kappa B-alpha degradation. Furthermore, cordycepin potently inhibited the binding of LPS to macrophages and LPS-induced Toll-like receptor 4 and myeloid differentiation factor 88 expression. Taken together, the results suggest that the inhibitory effects of cordycepin on LPS-stimulated inflammatory responses in RAW 264.7 macrophages are associated with suppression of mitogen-activating protein kinases and activation of NF-κB by inhibition of the Toll-like receptor 4 signaling pathway. Keywords

  10. Protective actions of vitamin D in UVB induced skin cancer.

    Science.gov (United States)

    Bikle, Daniel D

    2012-12-01

    Non-melanoma skin cancers (NMSC) are the most common type of cancer, occurring at a rate of over 1 million per year in the United States. Although their metastatic potential is generally low, they can and do metastasize, especially in the immune compromised host, and their surgical treatment is often quite disfiguring. Ultraviolet radiation (UVR) as occurs with sunlight exposure is generally regarded as causal for these malignancies, but UVR is also required for vitamin D synthesis in the skin. Based on our own data and that reported in the literature, we hypothesize that the vitamin D produced in the skin serves to suppress UVR epidermal tumor formation. In this review we will first discuss the evidence supporting the conclusion that the vitamin D receptor (VDR), with or without its ligand 1,25-dihydroxyvitamin D, limits the propensity for cancer formation following UVR. We will then explore three potential mechanisms for this protection: inhibition of proliferation and stimulation of differentiation, immune regulation, and stimulation of DNA damage repair (DDR).

  11. Quercitrin protects skin from UVB-induced oxidative damage.

    Science.gov (United States)

    Yin, Yuanqin; Li, Wenqi; Son, Young-Ok; Sun, Lijuan; Lu, Jian; Kim, Donghern; Wang, Xin; Yao, Hua; Wang, Lei; Pratheeshkumar, Poyil; Hitron, Andrew J; Luo, Jia; Gao, Ning; Shi, Xianglin; Zhang, Zhuo

    2013-06-01

    Exposure of the skin to ultraviolet B (UVB) radiation causes oxidative damage to skin, resulting in sunburn, photoaging, and skin cancer. It is generally believed that the skin damage induced by UV irradiation is a consequence of generation of reactive oxygen species (ROS). Recently, there is an increased interest in the use of natural products as chemopreventive agents for non-melanoma skin cancer (NMSC) due to their antioxidants and anti-inflammatory properties. Quercitrin, glycosylated form of quercetin, is the most common flavonoid in nature with antioxidant properties. The present study investigated the possible beneficial effects of quercitrin to inhibit UVB irradiation-induced oxidative damage in vitro and in vivo. Our results showed that quercitrin decreased ROS generation induced by UVB irradiation in JB6 cells. Quercitrin restored catalase expression and GSH/GSSG ratio reduced by UVB exposure, two major antioxidant enzymes, leading to reductions of oxidative DNA damage and apoptosis and protection of the skin from inflammation caused by UVB exposure. The present study demonstrated that quercitrin functions as an antioxidant against UVB irradiation-induced oxidative damage to skin.

  12. Improvement effect of corn silk, perilla leaf and grape stem extract mixture against UVB-induced skin damage and compound 48/80-induced pruritus

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Byoung Ok; Shin, Jae Young; Che, Denis Nchang; Hwang, Young Min; Lee, Hyun Seo; Choi, Ji Won; Jang, Seon Il [Jeonju University, Jeonju (Korea, Republic of); Ryu, Cheol [Hyangmiwon Corporation, Gimje (Korea, Republic of)

    2017-02-15

    This study was conducted to evaluate the synergistic protective effects of mixtures of corn silk, perilla leaf and grape stem extract (CPG mixture) against UVB-induced skin damage and compound 48/80-induced pruritus in mice. The results showed that treatment with CPG mixture exhibited much stronger suppressive effect on erythema and melanin index as well as melanin formation than treatment with ascorbic acid (AA) in UVB-irradiated mice. Moreover, the treatment with CPG mixture showed ameliorative effect on immune cell infiltration and collagen fiber destruction in UV-irradiated mice. The treatment with CPG mixture inhibited glutathione (GSH) depletion, lipid peroxidation and production of pro-inflammatory cytokines in UVB-irradiated mice. Furthermore, the treatment with CPG mixture inhibited compound 48/80-induced scratching behavior and histological changes in mice. Taken together, these results indicated that CPG mixture has potentials as functional and therapeutic materials against skin damage and itch-related skin diseases.

  13. The protective effect of Kaempferia parviflora extract on UVB-induced skin photoaging in hairless mice.

    Science.gov (United States)

    Park, Ji-Eun; Pyun, Hee-Bong; Woo, Seon Wook; Jeong, Jae-Hong; Hwang, Jae-Kwan

    2014-10-01

    Chronic skin exposure to ultraviolet (UV) light increases reactive oxygen species (ROS) and stimulates the expression of matrix metalloproteinases (MMPs) through c-Jun and c-Fos activation. These signaling cascades induce the degradation of extracellular matrix (ECM) components, resulting in photoaging. This study evaluated the preventive effect of the ethanol extract of Kaempferia parviflora Wall. ex. Baker (black ginger) on UVB-induced photoaging in vivo. To investigate the antiphotoaging effect of K. parviflora extract (KPE), UVB-irradiated hairless mice administered oral doses of KPE (100 or 200 mg/kg/day) for 13 weeks. In comparison to the UVB control group, KPE significantly prevented wrinkle formation and the loss of collagen fibers with increased type I, III, and VII collagen genes (COL1A1, COL3A1, and COL7A1). The decrease in wrinkle formation was associated with a significant reduction in the UVB-induced expression of MMP-2, MMP-3, MMP-9, and MMP-13 via the suppression of c-Jun and c-Fos activity. KPE also increased the expression of catalase, which acts as an antioxidant enzyme in skin. In addition, expression of inflammatory mediators, such as nuclear factor kappa B (NF-κB), interleukin-1β (IL-1β), and cyclooxygenase-2 (COX-2), was significantly reduced by KPE treatment. The results show that oral administration of KPE significantly prevents UVB-induced photoaging in hairless mice, suggesting its potential as a natural antiphotoaging material. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Recall of UVB-induced erythema in breast cancer patient receiving multiple drug chemotherapy

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Lindskov, R

    1984-01-01

    One day after sunbathing, a breast cancer patient received intravenous methotrexate, cyclophosphamide and 5-fluorouracil and had a recall of her UV erythema over the following week. Phototesting with UVA and UVB prior to and after a subsequent chemotherapy treatment showed a UVB-induced recall...... of erythema, as well as a phototoxicity-like response. Skin biopsies from test sites were compatible with phototoxic dermatitis. The occurrence of both erythema recall and the phototoxicity-like reaction suggests that more than one mechanism is involved in this side effect....

  15. Caspase-1 activity is required for UVB-induced apoptosis of human keratinocytes.

    Science.gov (United States)

    Sollberger, Gabriel; Strittmatter, Gerhard E; Grossi, Serena; Garstkiewicz, Martha; Auf dem Keller, Ulrich; French, Lars E; Beer, Hans-Dietmar

    2015-05-01

    Caspase-1 has a crucial role in innate immunity as the protease activates the proinflammatory cytokine prointerleukin(IL)-1β. Furthermore, caspase-1 induces pyroptosis, a lytic form of cell death that supports inflammation. Activation of caspase-1 occurs in multi-protein complexes termed inflammasomes, which assemble upon sensing of stress signals. In the skin and in skin-derived keratinocytes, UVB irradiation induces inflammasome-dependent IL-1 secretion and sunburn. Here we present evidence that caspase-1 and caspase-4 are required for UVB-induced apoptosis. In UVB-irradiated human primary keratinocytes, apoptosis occurs significantly later than inflammasome activation but depends on caspase-1 activity. However, it proceeds independently of inflammasome activation. By a proteomics approach, we identified the antiapoptotic Bap31 as a putative caspase-1 substrate. Caspase-1-dependent apoptosis is possibly a recent process in evolution as it was not detected in mice. These results suggest a protective role of caspase-1 in keratinocytes during UVB-induced skin cancer development through the induction of apoptosis.

  16. Protective effects of Aloe sterols against UVB-induced photoaging in hairless mice.

    Science.gov (United States)

    Misawa, Eriko; Tanaka, Miyuki; Saito, Marie; Nabeshima, Kazumi; Yao, Ruiqing; Yamauchi, Kouji; Abe, Fumiaki; Yamamoto, Yuki; Furukawa, Fukumi

    2017-03-01

    Aloe vera is a traditional medical plant whose gel has been widely used in skin care. Previously, we have identified Aloe sterols from Aloe vera as active ingredients. This study investigated the protective effects of Aloe sterols without polysaccharides, against ultraviolet B (UVB)-induced skin photoaging in mice using Aloe vera gel extract (AVGE) obtained by supercritical fluid extraction. Aloe vera gel extract was supplemented in the diet (12 or 120 ppm), and HR-1 hairless mice were exposed to UVB irradiation for 7 weeks. Skin measurements and histological and analytical studies were performed. Repeated UVB irradiation induced rough wrinkling of skin with water content reduction and hyperkeratosis. AVGE administration resulted in the significant improvement of UVB-induced skin dryness, epidermal thickness, and wrinkle formation. The AVGE group also suppressed the degenerations of dermal collagen fibers and the appearance of cutaneous apoptosis cells induced by UVB. Furthermore, AVGE administration reduced the excess elevation of pro-inflammatory cytokines (IL-1β and TNF-α) and matrix metalloproteinases (MMP-2, MMP-9, MMP-12, and MMP-13) in UVB-exposed skin. The dietary ingestion of Aloe sterols protected against chronic UVB damage in mouse skin, and our results suggest that Aloe sterols may prevent skin photoaging through the anti-inflammation and MMP regulation. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Role of vitamin D3 in modulation of ΔNp63α expression during UVB induced tumor formation in SKH-1 mice.

    Directory of Open Access Journals (Sweden)

    Natasha T Hill

    Full Text Available ΔNp63α, a proto-oncogene, is up-regulated in non-melanoma skin cancers and directly regulates the expression of both Vitamin D receptor (VDR and phosphatase and tensin homologue deleted on chromosome ten (PTEN. Since ΔNp63α has been shown to inhibit cell invasion via regulation of VDR, we wanted to determine whether dietary Vitamin D3 protected against UVB induced tumor formation in SKH-1 mice, a model for squamous cell carcinoma development. We examined whether there was a correlation between dietary Vitamin D3 and ΔNp63α, VDR or PTEN expression in vivo in SKH-1 mice chronically exposed to UVB radiation and fed chow containing increasing concentrations of dietary Vitamin D3. Although we observed differential effects of the Vitamin D3 diet on ΔNp63α and VDR expression in chronically irradiated normal mouse skin as well as UVB induced tumors, Vitamin D3 had little effect on PTEN expression in vivo. While low-grade papillomas in mice exposed to UV and fed normal chow displayed increased levels of ΔNp63α, expression of both ΔNp63α and VDR was reduced in invasive tumors. Interestingly, in mice fed high Vitamin D3 chow, elevated levels of ΔNp63α were observed in both local and invasive tumors but not in normal skin suggesting that oral supplementation with Vitamin D3 may increase the proliferative potential of skin tumors by increasing ΔNp63α levels.

  18. Topical application of glycolic acid suppresses the UVB induced IL-6, IL-8, MCP-1 and COX-2 inflammation by modulating NF-κB signaling pathway in keratinocytes and mice skin.

    Science.gov (United States)

    Tang, Sheau-Chung; Liao, Pei-Yun; Hung, Sung-Jen; Ge, Jheng-Siang; Chen, Shiou-Mei; Lai, Ji-Ching; Hsiao, Yu-Ping; Yang, Jen-Hung

    2017-06-01

    Glycolic acid (GA), commonly present in fruits, has been used to treat dermatological diseases. Extensive exposure to solar ultraviolet B (UVB) irradiation plays a crucial role in the induction of skin inflammation. The development of photo prevention from natural materials represents an effective strategy for skin keratinocytes. The aim of this study was to investigate the molecular mechanisms underlying the glycolic acid (GA)-induced reduction of UVB-mediated inflammatory responses. We determined the effects of different concentrations of GA on the inflammatory response of human keratinocytes HaCaT cells and C57BL/6J mice dorsal skin. After GA was topically applied, HaCaT and mice skin were exposed to UVB irradiation. GA reduced the production of UVB-induced nuclear factor kappa B (NF-κB)-dependent inflammatory mediators [interleukin (IL)-1β, IL-6, IL-8, cyclooxygenase (COX)-2, tumor necrosis factor-α, and monocyte chemoattractant protein (MCP-1)] at both mRNA and protein levels. GA inhibited the UVB-induced promoter activity of NF-κB in HaCaT cells. GA attenuated the elevation of senescence associated with β-galactosidase activity but did not affect the wound migration ability. The topical application of GA inhibited the genes expression of IL-1β, IL-6, IL-8, COX-2, and MCP-1 in UVB-exposed mouse skin. The mice to UVB irradiation after GA was topically applied for 9 consecutive days and reported that 1-1.5% of GA exerted anti-inflammatory effects on mouse skin. We clarified the molecular mechanism of GA protection against UVB-induced inflammation by modulating NF-κB signaling pathways and determined the optimal concentration of GA in mice skin exposed to UVB irradiation. Copyright © 2017 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.

  19. Angiotensin-converting enzyme inhibitor (enalapril maleate) accelerates recovery of mouse skin from UVB-induced wrinkles

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    Matsuura-Hachiya, Yuko; Arai, Koji Y.; Ozeki, Rieko; Kikuta, Ayako; Nishiyama, Toshio, E-mail: toshio_n@cc.tuat.ac.jp

    2013-12-06

    Highlights: •Angiotensin converting enzyme (ACE) increases in UVB-irradiated skin. •Administration of an ACE inhibitor improved UVB-induced skin wrinkle. •ACE inhibitor improved UVB-induced epidermal hypertrophy. •ACE inhibitor improved transepidermal water loss in the UVB-irradiated skin. -- Abstract: Angiotensin-converting enzyme (ACE) activity and angiotensin II signaling regulate cell proliferation, differentiation, and tissue remodeling, as well as blood pressure, while in skin, angiotensin II signaling is involved in wound healing, inflammation, and pathological scar formation. Therefore, we hypothesized that angiotensin II is also involved in photoaging of skin. In this study, we examined the effect of enalapril maleate, an ACE inhibitor, on recovery of wrinkled skin of hairless mice exposed to long-term UVB irradiation. Immunohistochemical observation revealed that expression of ACE, angiotensin II, and angiotensin II type 1 (AT1) and type 2 (AT2) receptors in the skin was increased after UVB irradiation (3 times/week at increasing intensities for 8 weeks). Administration of enalapril maleate (5 times/week for 6 weeks, starting 1 week after 10-week irradiation) accelerated recovery from UVB-induced wrinkles, epidermal hyperplasia and epidermal barrier dysfunction, as compared with the vehicle control. Our results indicate that ACE and angiotensin II activity are involved in skin photoaging, and suggest that ACE inhibitor such as enalapril maleate may have potential for improvement of photoaged skin.

  20. A comparative study of baby immature and adult shoots of Aloe vera on UVB-induced skin photoaging in vitro.

    Science.gov (United States)

    Hwang, Eunson; Kim, Su Hyeon; Lee, Sarah; Lee, Choong Hwan; Do, Seon-Gil; Kim, Jinwan; Kim, Sun Yeou

    2013-12-01

    Ultraviolet (UV) irradiation induces photo-damage of the skin, which in turn causes depletion of the dermal extracellular matrix and chronic alterations in skin structure. Skin wrinkle formations are associated with collagen synthesis and matrix metalloproteinase (MMP) expression. The production of type I procollagen is regulated by transforming growth factor-β1 (TGF-β1) expression; the activation of MMP is also correlated with an increase of interleukin-6 (IL-6). Aloe barbadensis M. (Aloe vera) is widely used in cosmetic and pharmaceutical products. In this study, we examined whether baby aloe shoot extract (BAE, immature aloe extract), which is from the one-month-old shoots of Aloe vera, and adult aloe shoot extract (AE), which is from the four-month-old shoots of Aloe vera, have a protective effect on UVB-induced skin photoaging in normal human dermal fibroblasts (NHDFs). The effects of BAE and AE on UVB-induced photoaging were tested by measuring the levels of reactive oxygen species, MMP-1, MMP-3, IL-6, type I procollagen, and TGF-β1 after UVB irradiation. We found that NHDF cells treated with BAE after UVB-irradiation suppressed MMP-1, MMP-3, and IL-6 levels compared to the AE-treated cells. Furthermore, BAE treatment elevated type I procollagen and TGF-β1 levels. Our results suggest that BAE may potentially protect the skin from UVB-induced damage more than AE.

  1. Development of High Cordycepin-Producing Cordyceps militaris Strains.

    Science.gov (United States)

    Kang, Naru; Lee, Hyun-Hee; Park, Inmyoung; Seo, Young-Su

    2017-03-01

    Cordyceps militaris, known as Dong-Chong-Xia-Cao, produces the most cordycepin among Cordyceps species and can be cultured artificially. For these reasons, C. militaris is widely used as herb or functional food in the East Asia. In this study, we developed a new strain of C. militaris that produces higher cordycepin content than parent strains through mating-based sexual reproduction. Twenty parent strains were collected and identified as C. militaris based on internal trasncrived spacer and rDNA sequences. Seven single spores of MAT 1-1 idiomorph and five single spores of MAT 1-2 idiomorph were isolated from 12 parent strains. When 35 combinations were mated on the brown rice medium with the isolated single spores, eight combinations formed a stroma with a normal perithecia and confirmed mated strains. High pressure liquid chromatography analysis showed that mated strain KSP8 produced the most cordycepin in all the media among all the tested strains. This result showed due to genetic recombination occurring during the sexual reproduction of C. militaris. The development of C. militaris strain with increased cordycepin content by this approach can help not only to generate new C. militaris strains, but also to contribute to the health food or medicine industry.

  2. Synergic Effect of Genistein and Daidzein on UVB-Induced DNA Damage: An Effective Photoprotective Combination

    Directory of Open Access Journals (Sweden)

    Barbara Iovine

    2011-01-01

    Full Text Available The anti-inflammatory effects and antioxidant activities of individual isoflavones are well established although little is known about the photoprotective effect of their combination. The aim of this study was to investigate the photoprotective effects of different concentrations of genistein and daidzein individually or combined. We measured the expression levels of the cyclo-oxygenase-2 (COX-2 and growth arrest and DNA-damage inducible (Gadd45 genes, which are involved in inflammation and DNA repair, respectively, in BJ-5ta human skin fibroblasts irradiated with 60 mJ/cm2 UVB. We also determined the cellular response to UVB-induced DNA damage by Comet assay. We report that genistein and daidzein when administered combined, and at a specific concentration and ratio, exerted a synergistic photoprotective effect that was greater than the effect obtained with each isoflavone alone. The results reported herein suggest that low concentrations of genistein and daidzein combined may be good candidate ingredients for protective agents against UV-induced photodamage.

  3. UVB-induced gene expression in the skin of Xiphophorus maculatus Jp 163 B.

    Science.gov (United States)

    Yang, Kuan; Boswell, Mikki; Walter, Dylan J; Downs, Kevin P; Gaston-Pravia, Kimberly; Garcia, Tzintzuni; Shen, Yingjia; Mitchell, David L; Walter, Ronald B

    2014-06-01

    Xiphophorus fish and interspecies hybrids represent long-standing models to study the genetics underlying spontaneous and induced tumorigenesis. The recent release of the Xiphophorus maculatus genome sequence will allow global genetic regulation studies of genes involved in the inherited susceptibility to UVB-induced melanoma within select backcross hybrids. As a first step toward this goal, we report results of an RNA-Seq approach to identify genes and pathways showing modulated transcription within the skin of X. maculatus Jp 163 B upon UVB exposure. X. maculatus Jp 163 B were exposed to various doses of UVB followed by RNA-Seq analysis at each dose to investigate overall gene expression in each sample. A total of 357 genes with a minimum expression change of 4-fold (p-adjbasal expression level of each transcript for each skin sample, (2) the changes in expression levels for each gene in the transcriptome upon exposure to increasing doses of UVB, and (3) clusters of genes that exhibit similar patterns of change in expression upon UVB exposure. These data provide a foundation for understanding the molecular genetic response of fish skin to UVB exposure.

  4. Determination of Cordycepin in Cordyceps kyushuensis by Capillary Electrophoresis and its Antitumour Activity

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A simple, rapid and low-cost method of determination for cordycepin in Cordyceps kyushuensis by capillary zone electrophoresis (CZE) was developed. Based on the finding that there is a high concentration of cordycepin in both natural and cultured Cordyceps kyushuensis, the in vitro antitumor activity of cordycepin and the water extracts of Cordyceps kyushuensis has been investigated. This is the first report about the antitumor effect of Cordyceps kyushuensis.

  5. Cordycepin Increases Nonrapid Eye Movement Sleep via Adenosine Receptors in Rats

    Directory of Open Access Journals (Sweden)

    Zhenzhen Hu

    2013-01-01

    Full Text Available Cordycepin (3′-deoxyadenosine is a naturally occurring adenosine analogue and one of the bioactive constituents isolated from Cordyceps militaris/Cordyceps sinensis, species of the fungal genus Cordyceps. It has traditionally been a prized Chinese folk medicine for the human well-being. Because of similarity of chemical structure of adenosine, cordycepin has been focused on the diverse effects of the central nervous systems (CNSs, like sleep regulation. Therefore, this study was undertaken to know whether cordycepin increases the natural sleep in rats, and its effect is mediated by adenosine receptors (ARs. Sleep was recorded using electroencephalogram (EEG for 4 hours after oral administration of cordycepin in rats. Sleep architecture and EEG power spectra were analyzed. Cordycepin reduced sleep-wake cycles and increased nonrapid eye movement (NREM sleep. Interestingly, cordycepin increased θ (theta waves power density during NREM sleep. In addition, the protein levels of AR subtypes (A1, A2A, and A2B were increased after the administration of cordycepin, especially in the rat hypothalamus which plays an important role in sleep regulation. Therefore, we suggest that cordycepin increases theta waves power density during NREM sleep via nonspecific AR in rats. In addition, this experiment can provide basic evidence that cordycepin may be helpful for sleep-disturbed subjects.

  6. Dietary grape-seed proanthocyanidin inhibition of ultraviolet B-induced immune suppression is associated with induction of IL-12.

    Science.gov (United States)

    Sharma, Som D; Katiyar, Santosh K

    2006-01-01

    We have shown previously that dietary grape seed proanthocyanidins (GSPs) inhibit UVB-induced photocarcinogenesis in mice. As UVB-induced immune suppression has been implicated in the development of skin cancer risk, we investigated whether dietary GSPs can modulate the effects of UVB on the immune system. We found that the UVB-induced (180 mJ/cm2) ear swelling response (inflammatory reaction) was significantly lower in mice fed with a GSP-supplemented (0.5 and 1.0%, w/w) diet than mice fed with the standard AIN76A diet. Dietary GSPs markedly inhibited UVB-induced (180 mJ/cm2) suppression of contact hypersensitivity responses in a local model of immunosuppression but had only moderate inhibitory effect in a systemic model of immunosuppression. Dietary GSPs reduced the UVB-induced increase in immunosuppressive cytokine interleukin (IL)-10 in skin and draining lymph nodes compared with mice that did not receive GSPs. In contrast, GSPs enhanced the production of immunostimulatory cytokine IL-12 in the draining lymph nodes. Intraperitoneal injection of GSPs-fed mice with a neutralizing anti-IL-12 antibody abrogated the protective effects of the GSPs against UVB-induced suppression of the contact hypersensitivity response. These data indicate for the first time that GSPs modulate UVB-induced immunosuppression and suggest that this may be one of the possible mechanisms by which they prevent photocarcinogenesis in mice.

  7. High expression of Mcl-1L via the MEK-ERK-phospho-STAT3 (Ser727) pathway protects melanocytes and melanoma from UVB-induced apoptosis.

    Science.gov (United States)

    Fukumoto, Takeshi; Iwasaki, Tetsushi; Okada, Taro; Hashimoto, Takanori; Moon, Youbin; Sakaguchi, Masanobu; Fukami, Yasuo; Nishigori, Chikako; Oka, Masahiro

    2016-02-01

    Ultraviolet (UV) B is a major factor in melanomagenesis. This fact is linked to the resistance of melanocytes to UVB-induced apoptosis. In this study, we characterized the involvement of Mcl-1L in the regulation of UVB-induced apoptosis in melanocytes and in melanoma cells. In melanocytes, apoptosis was not evident at 24 h after UVB irradiation. The Mcl-1L expression increased after UVB irradiation, and the high Mcl-1L expression continued for at least 24 h. This UVB-dependent increase in Mcl-1L was mediated by the MEK-ERK-pS-STAT3 (STAT3 phosphorylated at Ser727) pathway. The Ser727 phosphorylation facilitated nuclear localization of STAT3. In melanoma cells, the expression levels of Mcl-1L varied depending on the cell line. WM39 melanoma cells expressed high levels of Mcl-1L via the MEK-ERK-pS-STAT3 pathway and were resistant to UVB-induced apoptosis without up-regulation of Mcl-1L. In melanocytes and in WM39 cells, transfection with Mcl-1 siRNA promoted UVB-induced apoptosis. Immunohistochemical studies showed that melanoma cells in in situ lesions expressed high amounts of Mcl-1L. These results indicate that the high expression of Mcl-1L mediated by the MEK-ERK-pS-STAT3 pathway protects melanocytes and melanoma cells from UVB-induced apoptosis.

  8. Study on Intercalative Nanohybrid of Cordycepin in Layered Double Hydroxide

    Institute of Scientific and Technical Information of China (English)

    Jian Ya LING; Jing YANG; Qin Zheng YANG; Jun Feng PENG; Han Xing ZHANG; Chang Kai ZHANG

    2003-01-01

    A novel negatively charged biomolecule-cordycepin has been intercalated within thegallery spaces of [Mg-Al-NO3]. Results of TEM, PXRD and FT-IR spectroscopy confirmed thatcordycepin could be intercalated into [Mg-Al-NO3] interlayers as the charge-compensating species.Initial studies suggest that the new bioinorganic nanocomposite may be used as a novel inorganicreservoir or carrier of pharmaceutically active compounds.

  9. Osteoprotective Effect of Cordycepin on Estrogen Deficiency-Induced Osteoporosis In Vitro and In Vivo

    Directory of Open Access Journals (Sweden)

    Da-wei Zhang

    2015-01-01

    Full Text Available The purpose of this study was to verify the effect of cordycepin on ovariectomized osteopenic rats. Fifty Wistar female rats used were divided into 5 groups: (1 sham-operation rats (control, (2 ovariectomized (OVX rats with osteopenia, and (3 OVX’d rats with osteopenia treated with cordycepin (5 mg, 10 mg, and 20 mg for 8 weeks. After the rats were treated orally with cordycepin, serum alkaline phosphatase (ALP, tartrate resistant acid phosphatase (TRAP, serum osteocalcin (OC, homocysteine (HCY , C-terminal crosslinked telopeptides of collagen type I (CTX level, and oxidative stress were examined, respectively. The femoral neck was used for mechanical compression testing. At the same time, we further investigated the effect of cordycepin in vitro assay. The beneficial effects of cordycepin on improvement of osteoporosis in rats were attributable mainly to decrease ALP activity, TRAP activity, and CTX level. At the same time, cordycepin also increases the OC level in ovariectomized osteopenic rats. The histological examination clearly showed that dietary cordycepin can prevent bone loss caused by estrogen deficiency. These experimental results suggest that complement cordycepin is protective after ovariectomized osteopenic in specific way.

  10. Osteoprotective effect of cordycepin on estrogen deficiency-induced osteoporosis in vitro and in vivo.

    Science.gov (United States)

    Zhang, Da-wei; Deng, Hualiang; Qi, Wei; Zhao, Guang-yue; Cao, Xiao-rui

    2015-01-01

    The purpose of this study was to verify the effect of cordycepin on ovariectomized osteopenic rats. Fifty Wistar female rats used were divided into 5 groups: (1) sham-operation rats (control), (2) ovariectomized (OVX) rats with osteopenia, and (3) OVX'd rats with osteopenia treated with cordycepin (5 mg, 10 mg, and 20 mg) for 8 weeks. After the rats were treated orally with cordycepin, serum alkaline phosphatase (ALP), tartrate resistant acid phosphatase (TRAP), serum osteocalcin (OC), homocysteine (HCY) , C-terminal crosslinked telopeptides of collagen type I (CTX) level, and oxidative stress were examined, respectively. The femoral neck was used for mechanical compression testing. At the same time, we further investigated the effect of cordycepin in vitro assay. The beneficial effects of cordycepin on improvement of osteoporosis in rats were attributable mainly to decrease ALP activity, TRAP activity, and CTX level. At the same time, cordycepin also increases the OC level in ovariectomized osteopenic rats. The histological examination clearly showed that dietary cordycepin can prevent bone loss caused by estrogen deficiency. These experimental results suggest that complement cordycepin is protective after ovariectomized osteopenic in specific way.

  11. Effects of magnolol on UVB-induced skin cancer development in mice and its possible mechanism of action

    Directory of Open Access Journals (Sweden)

    Chilampalli Chandeshwari

    2011-10-01

    Full Text Available Abstract Background Magnolol, a plant lignan isolated from the bark and seed cones of Magnolia officinalis, has been shown to have chemopreventive effects on chemically-induced skin cancer development. The objectives of this investigation are to study the anticarcinogenic effects of magnolol on UVB-induced skin tumor development in SKH-1 mice, a model relevant to humans, and determine the possible role of apoptosis and cell cycle arrest involved in the skin tumor development. Methods UVB-induced skin carcinogenesis model in SKH-1 mice was used for determining the preventive effects of magnolol on skin cancer development. Western blottings and flow cytometric analysis were used to study the effects of magnolol on apoptosis and cell cycle. Results Magnolol pretreated groups (30, 60 μ g before UVB treatments (30 mJ/cm2, 5 days/week resulted in 27-55% reduction in tumor multiplicity as compared to control group in SKH-1 mice. Magnolol pretreatment increased the cleavage of caspase-8 and poly-(-ADP-ribose polymerase (PARP, increased the expression of p21, a cell cycle inhibitor, and decreased the expression of proteins involved in the G2/M phase of cell cycle in skin samples from SKH-1 mice. Treatment of A431 cells with magnolol decreased cell viability and cell proliferation in a concentration dependent manner. Magnolol induced G2/M phase cell cycle arrest in A431 cells at 12 h with a decreased expression of cell cycle proteins such as cyclin B1, cyclin A, CDK4, Cdc2 and simultaneous increase in the expression of Cip/p21, a cyclin-dependent kinase inhibitor. Magnolol induced apoptosis in vivo and in vitro with an increased cleavage of caspase-8 and PARP. Phospho-signal transducers and activators of transcription 3 (Tyr705, B-Raf, p-MEK, and p-AKT were down-regulated, whereas phosphorylation of ERK was induced by magnolol in A431 cells. Conclusions Magnolol pretreatments prevent UVB-induced skin cancer development by enhancing apoptosis, causing

  12. Separation of cordycepin from Cordyceps militaris fermentation supernatant using preparative HPLC and evaluation of its antibacterial activity as an NAD(+)-dependent DNA ligase inhibitor.

    Science.gov (United States)

    Zhou, Xiaofeng; Cai, Guoqiang; He, Yi; Tong, Guotong

    2016-09-01

    Cordycepin exhibits various bio-activities, including anticancer, antibacterial, antiviral and immune regulation activities, and is a significant focus of research. However, the preparation of high-purity cordycepin remains challenging. Also, the molecular target with which cordycepin interacts to cause an antibacterial effect remains unknown. In the present study, cordycepin was prepared by preparative high-performance liquid chromatography (prep-HPLC) and the purity obtained was 99.6%, indicating that this technique may be useful for the large-scale isolation of cordycepin in the future. The results of computational molecular docking analysis indicated that the interaction energy between cordycepin and NAD+-dependent DNA ligase (LigA) was lower than that between cordycepin and other common antibacterial targets. The highly pure cordycepin obtained by prep-HPLC demonstrated inhibitory activity against LigA from various bacteria in vitro. In conclusion, cordycepin may be useful as a broad-spectrum antibiotic targeting LigA in various bacteria.

  13. Gq protein mediates UVB-induced cyclooxygenase-2 expression by stimulating HB-EGF secretion from HaCaT human keratinocytes

    Energy Technology Data Exchange (ETDEWEB)

    Seo, MiRan [Department of Biochemistry and Molecular Biology and Cancer Research Institute, Seoul National University College of Medicine, Seoul (Korea, Republic of); Juhnn, Yong-Sung, E-mail: juhnn@snu.ac.kr [Department of Biochemistry and Molecular Biology and Cancer Research Institute, Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2010-03-05

    Ultraviolet (UV) radiation induces cyclooxygenase-2 expression to produce cellular responses including aging and carcinogenesis in skin. We hypothesised that heterotrimeric G proteins mediate UV-induced COX-2 expression by stimulating secretion of soluble HB-EGF (sHB-EGF). In this study, we aimed to elucidate the role and underlying mechanism of the {alpha} subunit of Gq protein (G{alpha}q) in UVB-induced HB-EGF secretion and COX-2 induction. We found that expression of constitutively active G{alpha}q (G{alpha}qQL) augmented UVB-induced HB-EGF secretion, which was abolished by knockdown of G{alpha}q with shRNA in HaCaT human keratinocytes. G{alpha}q was found to mediate the UVB-induced HB-EGF secretion by sequential activation of phospholipase C (PLC), protein kinase C{delta} (PKC{delta}), and matrix metaloprotease-2 (MMP-2). Moreover, G{alpha}qQL mediated UVB-induced COX-2 expression in an HB-EGF-, EGFR-, and p38-dependent manner. From these results, we concluded that G{alpha}q mediates UV-induced COX-2 expression through activation of EGFR by HB-EGF, of which ectodomain shedding was stimulated through sequential activation of PLC, PKC{delta} and MMP-2 in HaCaT cells.

  14. Oral administration of Aloe vera gel powder prevents UVB-induced decrease in skin elasticity via suppression of overexpression of MMPs in hairless mice.

    Science.gov (United States)

    Saito, Marie; Tanaka, Miyuki; Misawa, Eriko; Yao, Ruiquing; Nabeshima, Kazumi; Yamauchi, Kouji; Abe, Fumiaki; Yamamoto, Yuki; Furukawa, Fukumi

    2016-07-01

    This study reports the effects of oral Aloe vera gel powder (AVGP) containing Aloe sterols on skin elasticity and the extracellular matrix in ultraviolet B (UVB)-irradiated hairless mice. Ten-week-old hairless mice were fed diets containing 0.3% AVGP for 8 weeks and irradiated UVB for 6 weeks. Mice treated with AVGP showed significant prevention of the UVB-induced decrease in skin elasticity. To investigate the mechanism underlying this suppression of skin elasticity loss, we measured the expression of matrix metalloproteinase (MMP)-2, -9, and -13. AVGP prevented both the UVB-induced increases in MMPs expressions. Moreover, we investigated hyaluronic acid (HA) content of mice dorsal skin and gene expression of HA synthase-2 (Has2). In the results, AVGP oral administration prevented UVB-induced decreasing in skin HA content and Has2 expression and attenuates the UVB-induced decrease in serum adiponectin, which promotes Has2 expression. These results suggested that AVGP has the ability to prevent the skin photoaging.

  15. Mechanism of UVB-induced suppression of the immune responses to Mycobacterium bovis bacillus Calmette-Guerin: role of cytokines on macrophage function

    Energy Technology Data Exchange (ETDEWEB)

    Jeevan, Amminikutty; Ullrich, S.E.; Gracia, M. de; Shah, Rupa; Yan Sun [Texas Univ., Houston, TX (United States). Dept. of Immunology

    1996-08-01

    Previously we demonstrated that treatment of mice with either UVB radiation or supernatants derived from UVB-irradiated PAM 212 keratinocytes decreased the induction of the delayed-type hypersensitivity (DTH) response to Mycobacterium bovis bacillus Calmette-Guerin (BCG), impaired the clearance of bacteria from their lymphoid organs and also altered macrophage functions. In order to characterize the cytokines involved in these phenomena, UV-irradiated mice were injected with antibodies to interleukin-10 (IL-10), transforming growth factor-{beta}1 (TGF-{beta}1), or tumor necrosis factor-{alpha} (TNF-{alpha}). Injection of UVB-irradiated mice with anti-IL-10 immediately after UV irradiation restored the DTH response and reversed the UV-induced inhibition of bacterial clearance. Injection of UV-irradiated mice with anti-TGF-{beta} only partially restored the DTH response although it allowed a better clearance of BCG than injection of mice with the control antibody. In contrast, injection of anti-TNF-{alpha} did not affect the UVB-induced suppression of DTH or impaired bacterial clearance. Similarly, the ability of macrophages to phagocytose BCG and kill the intracellular organisms was restored to almost normal levels after injecting UV-irradiated mice with antibodies specific for IL-10 or TGF-{beta}. Injection of mice with either recombinant IL-10 or TGF-{beta} mimicked the effect of whole-body UV irradiation on immune function. These results suggest that IL-10 has a major role in UV-induced suppression of both DTH to BCG and impairment in the clearance of bacteria and that TGF-{beta} has a more significant role in blocking bacterial clearance. Futhermore, these cytokines seem to modulate immune responses by altering macrophage functions in UVB-irradiated mice. (Author).

  16. Coriander leaf extract exerts antioxidant activity and protects against UVB-induced photoaging of skin by regulation of procollagen type I and MMP-1 expression.

    Science.gov (United States)

    Hwang, Eunson; Lee, Do-Gyeong; Park, Sin Hee; Oh, Myung Sook; Kim, Sun Yeou

    2014-09-01

    Ultraviolet (UV) radiation causes photodamage to the skin, which, in turn, leads to depletion of the dermal extracellular matrix and chronic alterations in skin structure. Skin wrinkles are associated with collagen synthesis and matrix metalloproteinase-1 (MMP-1) activity. Coriandrum sativum L. (coriander leaf, cilantro; CS) has been used as a herbal medicine for the treatment of diabetes, hyperlipidemia, liver disease, and cancer. In this study, we examined whether CS ethanol extract (CSE) has protective effects against UVB-induced skin photoaging in normal human dermal fibroblasts (NHDF) in vitro and in the skin of hairless mice in vivo. The main component of CSE, linolenic acid, was determined by gas chromatography-mass spectroscopy. We measured the cellular levels of procollagen type I and MMP-1 using ELISA in NHDF cells after UVB irradiation. NHDF cells that were treated with CSE after UVB irradiation exhibited higher procollagen type I production and lower levels of MMP-1 than untreated cells. We found that the activity of transcription factor activator protein-1 (AP-1) was also inhibited by CSE treatment. We measured the epidermal thickness, dermal collagen fiber density, and procollagen type I and MMP-1 levels in photo-aged mouse skin in vivo using histological staining and western blot analysis. Our results showed that CSE-treated mice had thinner epidermal layers and denser dermal collagen fibers than untreated mice. On a molecular level, it was further confirmed that CSE-treated mice had lower MMP-1 levels and higher procollagen type I levels than untreated mice. Our results support the potential of C. sativum L. to prevent skin photoaging.

  17. Artocarpin-enriched (Artocarpus altilis) Heartwood Extract Provides Protection Against UVB-induced Mechanical Damage in Dermal Fibroblasts.

    Science.gov (United States)

    Tiraravesit, Narisara; Humbert, Philippe; Robin, Sophie; Tissot, Marion; Viennet, Céline; Viyoch, Jarupa

    2017-10-01

    This study aimed to evaluate the protective effect of artocarpin-enriched (Artocarpus altilis) heartwood extract on the mechanical properties of UVB-irradiated fibroblasts. Human skin fibroblasts were pretreated with 50 μg/mL(-1) extract and later irradiated with UVB (200 mJ/cm(-2) ). They were then cultured within three-dimensional of free-floating and tense collagen lattices. The pretreatment of fibroblasts with the extract prior to UVB radiation showed cells protection against UVB-induced suppression of α-SMA expression, fibroblast migration and contraction. These results reveal that the extract prevents mechanical damages induced by UVB irradiation in fibroblast-embedded collagen lattices, and therefore, has a potential as a natural photo-protectant. © 2017 The American Society of Photobiology.

  18. Cordyceps pruinosa produces cordycepin and N6-(2-hydroxyethyl-adenosine in culture

    Directory of Open Access Journals (Sweden)

    Meng Zebin

    2014-01-01

    Full Text Available Cordyceps species are entomophagous pathogens with medicinal properties, mostly linked to cordycepin and N6- (2-hydroxyethyl-adenosine (HEA. An isolate of Cordyceps pruinosa (GZUCC 8552 was obtained from a fruiting body formed on the cocoon a Limacodidae insect collected in Guizhou Province, China. Morphological and molecular analysis (combined 5.8S ITS, RPB1 and 18S RNA confirmed the species to be Cordyceps pruinosa. Metabolites of the isolate grown in liquid static and solid-state media were established by HPLC-MS. Cordycepin (5.311 mg/g and HEA (0.558 mg/g were produced by this strain. This is the first record of cordycepin from an isolate of Cordyceps pruinosa. As Cordyceps pruinosa is a good source of cordycepin and HEA, it could be used as an alternative to the over-collected Cordyceps sinensis.

  19. Toxicity evaluation of cordycepin and its delivery system for sustained in vitro anti-lung cancer activity

    Science.gov (United States)

    Aramwit, Pornanong; Porasuphatana, Supatra; Srichana, Teerapol; Nakpheng, Titpawan

    2015-03-01

    In the previous study, we have found that the cordycepin which was extracted from Cordyceps mycelia produced by growing Cordyceps militaris on the dead larva of Bombyx mori silkworms showed the anti-proliferative effect toward lung cancer cells without toxicity to non-cancer cells. In this work, the cordycepin was tested for its in vitro mutagenicity and in vivo toxicity. From the Ames test and subacute toxicity test using oral administration in a rat model, the cordycepin was proved to be a non-mutagenic and non-toxic compound. The hematology and blood chemistry as well as the microanatomical characteristic of the tissues of rats fed with cordycepin every day for consecutive 30 days were comparable to those of the normal ones. Then, the cordycepin was incorporated in gelatin type A (GA) and gelatin type B (GB) nanoparticles aimed to sustain its release and activity. The cordycepin incorporated in both GA and GB nanoparticles showed the sustained release profiles. GA nanoparticles could encapsulate cordycepin at higher encapsulation efficiency due to the attractive electrostatic interaction between the positive-charged GA and the negative-charged cordycepin. However, GA nanoparticles released cordycepin at the higher amount possibly because of the large surface area of small size nanoparticles. Comparing to GB nanoparticles, the higher amount of cordycepin released from GA nanoparticles showed the higher anti-proliferative and anti-migratory effects on A549 lung cancer cells. In conclusion, GA nanoparticles were suggested as a suitable carrier for the sustained release of cordycepin. The GA nanoparticles releasing cordycepin could be an effective and non-invasive material for the treatment of lung cancer cells.

  20. HPV 5 and 8 E6 abrogate ATR activity resulting in increased persistence of UVB induced DNA damage.

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    Nicholas A Wallace

    Full Text Available The role of the E6 oncoprotein from high-risk members of the α human papillomavirus genus in anogenital cancer has been well established. However, far less is known about the E6 protein from the β human papillomavirus genus (β-HPVs. Some β-HPVs potentially play a role in non-melanoma skin cancer development, although they are not required for tumor maintenance. Instead, they may act as a co-factor that enhances the carcinogenic potential of UV damage. Indeed, the E6 protein from certain β-HPVs (HPV 5 and 8 promotes the degradation of p300, a histone acetyl transferase involved in UV damage repair. Here, we show that the expression of HPV 5 and 8 E6 increases thymine dimer persistence as well as the likelihood of a UVB induced double strand break (DSB. Importantly, we provide a mechanism for the increased DNA damage by showing that both extended thymine dimer persistence as well as elevated DSB levels are dependent on the ability of HPV 8 E6 to promote p300 degradation. We further demonstrate that HPV 5 and 8 E6 expression reduces the mRNA and protein levels of ATR, a PI3 kinase family member that plays a key role in UV damage signaling, but that these levels remain unperturbed in cells expressing a mutated HPV 8 E6 incapable of promoting p300 degradation. We confirm that the degradation of p300 leads to a reduction in ATR protein levels, by showing that ATR levels rebound when a p300 mutant resistant to HPV 8 mediated degradation and HPV 8 E6 are co-transfected. Conversely, we show that ATR protein levels are reduced when p300 is targeted for degradation by siRNA. Moreover, we show the reduced ATR levels in HPV 5 and 8 E6 expressing cells results in delayed ATR activation and an attenuated ability of cells to phosphorylate, and as a result accumulate, p53 in response to UVB exposure, leading to significantly reduced cell cycle arrest. In conclusion, these data demonstrate that β-HPV E6 expression can enhance the carcinogenic potential of

  1. Improvement effect of gamma-irradiated complex leaf extract of date plum, persimmon and mulberry on UVB-induced skin damage

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Ji Won; Cho, Byoung Ok; Che, Denis Nchang; Shin, Jae Young; Fang, Chong Zhou; Jang, Seon Il [Jeonju University, Jeonju (Korea, Republic of)

    2016-11-15

    This study was conducted to evaluate the improvement effect of gamma-irradiated complex leaf extract of Date Plum, Persimmon and Mulberry (γ-DPME) on UVB induced skin damage. The samples were gamma irradiated at doses of 10 kGy. γ-DPME treatment tended to decrease UVB-induced immune cell infiltration and erthyderma index than the groups treated with non-gamma-irradiated DPME (n-DPME) and L-ascobic acid (AA). In addition, γ-DPME treatment significantly decreased skin thickness, melanin index and mast cell infiltration in UVB-irradiated skin. Moreover, γ-DPME treatment significantly decreased the compound 48/80-induced scratching behavior and immune cell infiltration than n-DPME group. These results show that gamma irradiation can be used to increase the physiological activities of DPME.

  2. Cordycepin and N6-(2-hydroxyethyl-adenosine from Cordyceps pruinosa and their interaction with human serum albumin.

    Directory of Open Access Journals (Sweden)

    Zebin Meng

    Full Text Available Cordyceps pruinosa (CP is often used as Traditional Chinese Medicine, but the substance basis of its medicinal properties is unclear. In this study, two compounds were isolated from CP cultures by column chromatography, and identified as cordycepin and N6-(2-hydroxyethyl-adenosine (HEA by Nuclear Magnetic Resonance. In order to understand the efficacy of these two substances as potential therapeutic agents, it is necessary to explore their binding with proteins. The molecular mechanisms of interaction between cordycepin, HEA and human serum albumin (HSA were studied using UV and fluorescence spectroscopy. The bingding constants between HSA and cordycepin were 4.227, 3.573 and 3.076 × 10(3·at 17, 27 and 37°C respectively, and that of HSA and HEA were 27.102, 19.409 and 13.002 × 10(3·at the three tempretures respectively. Both cordycepin and HEA can quench the intrinsic fluorescence of HSA via static quenching, and they can bind with HSA to form complexes with a single binding site. The interaction forces between cordycepin and HSA were determined as electrostatic and hydrophobic, and those of HEA and HSA were hydrogen bonding and van der Waals forces. Using Foster's equation, the distance between fluorophores of cordycepin and HSA, and HEA and HSA are estimated to be 5.31 nm and 4.98 nm, respectively. In this study, cordycepin was isolated for the first time from CP, and will provide a new source of cordycepin and expand the use of this taxon. The interaction mechanisms between cordycepin and HSA was studied for the first time, which will provide a useful guide for the clinical application of cordycepin. The pharmacological importance of this study is to understand the interaction of HSA with cordycepin and HEA, which will be essential for the future designing of drugs based on the two compounds.

  3. Cordycepin and N6-(2-Hydroxyethyl)-Adenosine from Cordyceps pruinosa and Their Interaction with Human Serum Albumin

    Science.gov (United States)

    Meng, Zebin; Kang, Jichuan; Wen, Tingchi; Lei, Bangxing; Hyde, Kevin David

    2015-01-01

    Cordyceps pruinosa (CP) is often used as Traditional Chinese Medicine, but the substance basis of its medicinal properties is unclear. In this study, two compounds were isolated from CP cultures by column chromatography, and identified as cordycepin and N6-(2-hydroxyethyl)-adenosine (HEA) by Nuclear Magnetic Resonance. In order to understand the efficacy of these two substances as potential therapeutic agents, it is necessary to explore their binding with proteins. The molecular mechanisms of interaction between cordycepin, HEA and human serum albumin (HSA) were studied using UV and fluorescence spectroscopy. The bingding constants between HSA and cordycepin were 4.227, 3.573 and 3.076 × 103·at 17, 27 and 37°C respectively, and that of HSA and HEA were 27.102, 19.409 and 13.002 × 103·at the three tempretures respectively. Both cordycepin and HEA can quench the intrinsic fluorescence of HSA via static quenching, and they can bind with HSA to form complexes with a single binding site. The interaction forces between cordycepin and HSA were determined as electrostatic and hydrophobic, and those of HEA and HSA were hydrogen bonding and van der Waals forces. Using Foster's equation, the distance between fluorophores of cordycepin and HSA, and HEA and HSA are estimated to be 5.31 nm and 4.98 nm, respectively. In this study, cordycepin was isolated for the first time from CP, and will provide a new source of cordycepin and expand the use of this taxon. The interaction mechanisms between cordycepin and HSA was studied for the first time, which will provide a useful guide for the clinical application of cordycepin. The pharmacological importance of this study is to understand the interaction of HSA with cordycepin and HEA, which will be essential for the future designing of drugs based on the two compounds. PMID:25811172

  4. An Ethanol Extract Derived from Bonnemaisonia hamifera Scavenges Ultraviolet B (UVB Radiation-Induced Reactive Oxygen Species and Attenuates UVB-Induced Cell Damage in Human Keratinocytes

    Directory of Open Access Journals (Sweden)

    Nam Ho Lee

    2012-12-01

    Full Text Available The present study investigated the photoprotective properties of an ethanol extract derived from the red alga Bonnemaisonia hamifera against ultraviolet B (UVB-induced cell damage in human HaCaT keratinocytes. The Bonnemaisonia hamifera ethanol extract (BHE scavenged the superoxide anion generated by the xanthine/xanthine oxidase system and the hydroxyl radical generated by the Fenton reaction (FeSO4 + H2O2, both of which were detected by using electron spin resonance spectrometry. In addition, BHE exhibited scavenging activity against the 1,1-diphenyl-2-picrylhydrazyl radical and intracellular reactive oxygen species (ROS that were induced by either hydrogen peroxide or UVB radiation. BHE reduced UVB-induced apoptosis, as shown by decreased apoptotic body formation and DNA fragmentation. BHE also attenuated DNA damage and the elevated levels of 8-isoprostane and protein carbonyls resulting from UVB-mediated oxidative stress. Furthermore, BHE absorbed electromagnetic radiation in the UVB range (280–320 nm. These results suggest that BHE protects human HaCaT keratinocytes against UVB-induced oxidative damage by scavenging ROS and absorbing UVB photons, thereby reducing injury to cellular components.

  5. An ethanol extract derived from Bonnemaisonia hamifera scavenges ultraviolet B (UVB) radiation-induced reactive oxygen species and attenuates UVB-induced cell damage in human keratinocytes.

    Science.gov (United States)

    Piao, Mei Jing; Hyun, Yu Jae; Cho, Suk Ju; Kang, Hee Kyoung; Yoo, Eun Sook; Koh, Young Sang; Lee, Nam Ho; Ko, Mi Hee; Hyun, Jin Won

    2012-12-14

    The present study investigated the photoprotective properties of an ethanol extract derived from the red alga Bonnemaisonia hamifera against ultraviolet B (UVB)-induced cell damage in human HaCaT keratinocytes. The Bonnemaisonia hamifera ethanol extract (BHE) scavenged the superoxide anion generated by the xanthine/xanthine oxidase system and the hydroxyl radical generated by the Fenton reaction (FeSO₄ + H₂O₂), both of which were detected by using electron spin resonance spectrometry. In addition, BHE exhibited scavenging activity against the 1,1-diphenyl-2-picrylhydrazyl radical and intracellular reactive oxygen species (ROS) that were induced by either hydrogen peroxide or UVB radiation. BHE reduced UVB-induced apoptosis, as shown by decreased apoptotic body formation and DNA fragmentation. BHE also attenuated DNA damage and the elevated levels of 8-isoprostane and protein carbonyls resulting from UVB-mediated oxidative stress. Furthermore, BHE absorbed electromagnetic radiation in the UVB range (280-320 nm). These results suggest that BHE protects human HaCaT keratinocytes against UVB-induced oxidative damage by scavenging ROS and absorbing UVB photons, thereby reducing injury to cellular components.

  6. Preclinical assessment of the treatment of second-stage African trypanosomiasis with cordycepin and deoxycoformycin.

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    Suman K Vodnala

    Full Text Available BACKGROUND: There is an urgent need to substitute the highly toxic compounds still in use for treatment of the encephalitic stage of human African trypanosomiasis (HAT. We here assessed the treatment with the doublet cordycepin and the deaminase inhibitor deoxycoformycin for this stage of infection with Trypanosoma brucei (T.b.. METHODOLOGY/PRINCIPAL FINDINGS: Cordycepin was selected as the most efficient drug from a direct parasite viability screening of a compound library of nucleoside analogues. The minimal number of doses and concentrations of the drugs effective for treatment of T.b. brucei infections in mice were determined. Oral, intraperitoneal or subcutaneous administrations of the compounds were successful for treatment. The doublet was effective for treatment of late stage experimental infections with human pathogenic T.b. rhodesiense and T.b. gambiense isolates. Late stage infection treatment diminished the levels of inflammatory cytokines in brains of infected mice. Incubation with cordycepin resulted in programmed cell death followed by secondary necrosis of the parasites. T.b. brucei strains developed resistance to cordycepin after culture with increasing concentrations of the compound. However, cordycepin-resistant parasites showed diminished virulence and were not cross-resistant to other drugs used for treatment of HAT, i.e. pentamidine, suramin and melarsoprol. Although resistant parasites were mutated in the gene coding for P2 nucleoside adenosine transporter, P2 knockout trypanosomes showed no altered resistance to cordycepin, indicating that absence of the P2 transporter is not sufficient to render the trypanosomes resistant to the drug. CONCLUSIONS/SIGNIFICANCE: Altogether, our data strongly support testing of treatment with a combination of cordycepin and deoxycoformycin as an alternative for treatment of second-stage and/or melarsoprol-resistant HAT.

  7. Involvement of inositol biosynthesis and nitric oxide in the mediation of UV-B induced oxidative stress

    Directory of Open Access Journals (Sweden)

    Dmytro I Lytvyn

    2016-04-01

    Full Text Available The involvement of NO-signaling in ultraviolet B (UV-B induced oxidative stress in plants is an open question. Inositol biosynthesis contributes to numerous cellular functions, including the regulation of plants tolerance to stress. This work reveals the involvement of inositol-3-phosphate synthase 1 (IPS1, a key enzyme for biosynthesis of myo-inositol and its derivatives, in the response to NO-dependent oxidative stress in Arabidopsis. Homozygous mutants deficient for IPS1 (atips1 and wild-type plants were transformed with a reduction-oxidation-sensitive green fluorescent protein 2 (grx1-rogfp2 and used for the dynamic measurement of UV-B-induced and SNP (sodium nitroprusside-mediated oxidative stresses by confocal microscopy. atips1 mutants displayed greater tissue-specific resistance to the action of UV-B than the wild type. SNP can act both as an oxidant or repairer depending on the applied concentration, but mutant plants were more tolerant than the wild type to nitrosative effects of high concentration of SNP. Additionally, pretreatment with low concentrations of SNP (10, 100 μM before UV-B irradiation resulted in a tissue-specific protective effect that was enhanced in atips1. We conclude that the interplay between nitric oxide and inositol signaling can be involved in the mediation of UV-B-initiated oxidative stress in the plant cell.

  8. Double trouble from sunburn: UVB-induced erythema is associated with a transient decrease in skin pigmentation.

    Science.gov (United States)

    Casetti, F; Miese, A; Mueller, M L; Simon, J C; Schempp, C M

    2011-01-01

    Ultraviolet B (UVB) radiation may cause an immediate inflammatory response followed by a delayed increase in skin pigmentation. The early time course of erythema and pigmentation has so far not been monitored simultaneously by photometric measurements. Test areas on the volar forearms of 15 volunteers were irradiated with 210 mJ/cm(2) UVB. Skin erythema and pigmentation were determined photometrically at time 0, after 6 h, and after 1, 2, 3 and 7 days. Punch biopsies were taken before irradiation, after 6 h and after 7 days. Melanocytes were stained using the DOPA method. UVB irradiation caused an increase in skin erythema at all time points, peaking at 24 h and slowly decreasing until day 7. Surprisingly, this was associated with a pronounced decrease in skin pigmentation at early readings. DOPA staining of melanocytes confirmed this observation. Only after 7 days was there an increase in skin pigmentation over the initial levels. Acute UVB-induced skin erythema seems to be associated with increased susceptibility to the deleterious effects of solar radiation due to a concomitant decrease in skin pigmentation. These findings underline the importance of avoiding even moderate sunburns and of slowly adapting the skin to solar radiation. Copyright © 2011 S. Karger AG, Basel.

  9. Sebaceous lipids are essential for water repulsion, protection against UVB-induced apoptosis and ocular integrity in mice.

    Science.gov (United States)

    Dahlhoff, Maik; Camera, Emanuela; Schäfer, Matthias; Emrich, Daniela; Riethmacher, Dieter; Foster, April; Paus, Ralf; Schneider, Marlon R

    2016-05-15

    Sebocytes, which are characterized by lipid accumulation that leads to cell disruption, can be found in hair follicle-associated sebaceous glands (SGs) or in free SGs such as the Meibomian glands in the eyelids. Because genetic tools that allow targeting of sebocytes while maintaining intact epidermal lipids are lacking, the relevance of sebaceous lipids in health and disease remains poorly understood. Using Scd3, which is expressed exclusively in mature sebocytes, we established a mouse line with sebocyte-specific expression of Cre recombinase. Both RT-PCR analysis and crossing into Rosa26-lacZ reporter mice and Kras(G12D) mice confirmed Cre activity specifically in SGs, with no activity in other skin compartments. Importantly, loss of SCD3 function did not cause detectable phenotypical alterations, endorsing the usefulness of Scd3-Cre mice for further functional studies. Scd3-Cre-induced, diphtheria chain A toxin-mediated depletion of sebaceous lipids resulted in impaired water repulsion and thermoregulation, increased rates of UVB-induced epidermal apoptosis and caused a severe pathology of the ocular surface resembling Meibomian gland dysfunction. This novel mouse line will be useful for further investigating the roles of sebaceous lipids in skin and eye integrity.

  10. Antiplatelet and antithrombotic effects of cordycepin-enriched WIB-801CE from Cordyceps militaris ex vivo, in vivo, and in vitro.

    Science.gov (United States)

    Kwon, Hyuk-Woo; Shin, Jung-Hae; Lim, Deok Hwi; Ok, Woo Jeong; Nam, Gi Suk; Kim, Min Ji; Kwon, Ho-Kyun; Noh, Jun-Hee; Lee, Je-Young; Kim, Hyun-Hong; Kim, Jong-Lae; Park, Hwa-Jin

    2016-12-07

    A species of the fungal genus Cordyceps has been used as a complementary and alternative medicine of traditional Chinese medicine, and its major component cordycepin and cordycepin-enriched WIB-801CE are known to have antiplatelet effects in vitro. However, it is unknown whether they have also endogenous antiplatelet and antithrombotic effects. In this study, to resolve these doubts, we prepared cordycepin-enriched WIB-801CE, an ethanol extract from Cordyceps militaris-hypha, then evaluated its ex vivo, in vivo, and in vitro antiplatelet and antithrombotic effects. Ex vivo effects of WIB-801CE on collagen- and ADP-induced platelet aggregation, serotonin release, thromboxane A2 (TXA2) production and its associated activities of enzymes [cyclooxygenase-1 (COX-1), TXA2 synthase (TXAS)], arachidonic acid (AA) release and its associated phosphorylation of phospholipase Cβ3, phospholipase Cγ2 or cytosolic phospholipase A2, mitogen-activated protein kinase (MAPK) [p(38 MAPK), extracellular signal-regulated kinase (ERK)], and blood coagulation time in rats were investigated. In vivo effects of WIB-801CE on collagen plus epinephrine-induced acute pulmonary thromboembolism, and tail bleeding time in mice were also inquired. In vitro effects of WIB-801CE on cytotoxicity, and fibrin clot retraction in human platelets, and nitric oxide (NO) production in RAW264.7 cells or free radical scavenging activity were studied. Cordycepin-enriched WIB-801CE inhibited ex vivo platelet aggregation, TXA2 production, AA release, TXAS activity, serotonin release, and p(38 MAPK) and ERK2 phosphorylation in collagen- and ADP-activated rat platelets without affecting blood coagulation. Furthermore, WIB-801CE manifested in vivo inhibitory effect on collagen plus epinephrine-induced pulmonary thromboembolism mice model. WIB-801CE inhibited in vitro NO production and fibrin clot retraction, but elevated free radical scavenging activity without affecting cytotoxicity against human platelets. WIB

  11. Effects of cordycepin on the microglia-overactivation-induced impairments of growth and development of hippocampal cultured neurons.

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    Jie Peng

    Full Text Available Microglial cells are normally activated in response to brain injury or immunological stimuli to protect central nervous system (CNS. However, over-activation of microglia conversely amplifies the inflammatory effects and mediates cellular degeneration, leading to the death of neurons. Recently, cordycepin, an active component found in Cordyceps militarisa known as a rare Chinese caterpillar fungus, has been reported as an effective drug for treating inflammatory diseases and cancer via unclear mechanisms. In this study, we attempted to identify the anti-inflammatory role of cordycepin and its protective effects on the impairments of neural growth and development induced by microglial over-activation. The results indicate that cordycepin could attenuate the lipopolysaccharide (LPS-induced microglial activation, evidenced by the dramatically reduced release of TNF-α and IL-1β, as well as the down-regulation of mRNA levels of iNOS and COX-2 after cordycepin treatment. Besides, cordycepin reversed the LPS-induced activation of NF-κB pathway, resulting in anti-inflammatory effects. Furthermore, by employing the conditioned medium (CM, we found cordycepin was able to recover the impairments of neural growth and development in the primary hippocampal neurons cultured in LPS-CM, including cell viability, growth cone extension, neurite sprouting and outgrowth as well as spinogenesis. This study expands our knowledge of the anti-inflammatory function of cordycepin and paves the way for the biomedical applications of cordycepin in the therapies of neural injuries.

  12. Extraction,Purification, and Antitumor Activity of Cordycepin from Cordyceps Militaris Residue Medium%北虫草培养残基中虫草素的提取纯化及抗肿瘤活性

    Institute of Scientific and Technical Information of China (English)

    陈丽冰; 吴光旭; 程薇; 范秀芝; 史德芳; 石猛; 高虹

    2016-01-01

    以北虫草固体培养残基为实验材料,比较闪式提取、超声波提取和超高压提取培养残基中虫草素的效果,用陶瓷膜过滤提取液,获得虫草素粗提液,利用高速逆流色谱分离制备虫草素,通过LC-MS/MS对产物结构进行鉴定,并验证了虫草素对小鼠S180肉瘤的抑制作用。结果显示,超高压提取培养基中虫草素较好,高速逆流色谱分离纯化条件是以V(乙酸乙酯):V(正丁醇):V(水)=2:3:5的两相溶剂系统,上相为固定相,下相为流动相,流速3.0 mL/min,主机转速900 r/min,分离温度28℃,以此分离条件经一步洗脱,高速逆流色谱收集馏分,其中峰Ⅲ产物经HPLC检测纯度达97.6%,结构经LC-MS/MS鉴定为虫草素。从100 g 北虫草培养残基中可制备得虫草素181.90 mg,并对其活性验证发现剂量为100 mg/kg时小鼠S180肉瘤瘤重抑制率为64.48%。%Flash extraction, ultrasonic extraction, and ultra-high pressure extraction technology were used to extract cordycepin from Cordyceps militaris residue medium. The extracting solution was filtered with ceramic membrane and cordycepin was separated and prepared by using high-speed countercurrent chro-matography ( HSCCC ) . The product structure was identified by LC-MS/MS. Antitumor activity of cordycepin was tested in mice S180 tumor. The results showed that ultra-high pressure extraction technol-ogy was better for cordycepin extraction. Combining a two-phase solvent system composed of ethyl ace-tate-n-butanol-water (2:3:5,V/V/V) with high-speed counter-current chromatography (HSCCC), the cordycepin was purified at 28℃ with flow rate of 3. 0 mL/min and revolution speed was 900 r/min, while the upper phase was stationary phase and the lower phase was mobile phase. Cordycepin identified was i-dentified by LC-MS/MS and the purity of cordycepin was 97. 6%. About 181. 90 mg of cordycepin was obtained from 100 g of Cordyceps militaris residue medium. The inhibition rate of cordycepin

  13. Cordycepin (3'-deoxyadenosine) down-regulates the proinflammatory cytokines in inflammation-induced osteoporosis model.

    Science.gov (United States)

    Zhang, Da-wei; Wang, Zhen-lin; Qi, Wei; Lei, Wei; Zhao, Guang-yue

    2014-08-01

    The effect of cordycepin (3'-deoxyadenosine) on inflammation-induced osteoporosis (IMO) was studied in this paper. After the rats were treated orally with cordycepin (20 mg/kg), serum osteocalcin (OC), homocysteine (HCY), C-terminal cross-linked telopeptides of collagen type I (CTX), maleic dialdehyde (MDA), polymorphonuclear cells (PMN), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α), they were examined by ELISA or immunohistochemistry. The specimens from the liver were also processed for light microscopic examination. The IMO rats showed a significant increase in plasma CTX, MDA, PMN, IL-1β, TNF-α, and nitrate levels as well as a significant decrease in plasma OC. These changes were attenuated by cordycepin (20 mg/kg) supplementation in the IMO rats. Examination of the liver specimens revealed mononuclear cell infiltration in the portal areas in the IMO rats which was not detected in the cordycepin (20 mg/kg) rats. These results suggest that cordycepin may act as an anti-inflammatory agent in magnesium silicate-induced inflammation in osteoporosis.

  14. Optimization of Large-Scale Culture Conditions for the Production of Cordycepin with Cordyceps militaris by Liquid Static Culture

    Directory of Open Access Journals (Sweden)

    Chao Kang

    2014-01-01

    Full Text Available Cordycepin is one of the most important bioactive compounds produced by species of Cordyceps sensu lato, but it is hard to produce large amounts of this substance in industrial production. In this work, single factor design, Plackett-Burman design, and central composite design were employed to establish the key factors and identify optimal culture conditions which improved cordycepin production. Using these culture conditions, a maximum production of cordycepin was 2008.48 mg/L for 700 mL working volume in the 1000 mL glass jars and total content of cordycepin reached 1405.94 mg/bottle. This method provides an effective way for increasing the cordycepin production at a large scale. The strategies used in this study could have a wide application in other fermentation processes.

  15. Optimization of Large-Scale Culture Conditions for the Production of Cordycepin with Cordyceps militaris by Liquid Static Culture

    Science.gov (United States)

    Kang, Chao; Wen, Ting-Chi; Kang, Ji-Chuan; Meng, Ze-Bing; Li, Guang-Rong; Hyde, Kevin D.

    2014-01-01

    Cordycepin is one of the most important bioactive compounds produced by species of Cordyceps sensu lato, but it is hard to produce large amounts of this substance in industrial production. In this work, single factor design, Plackett-Burman design, and central composite design were employed to establish the key factors and identify optimal culture conditions which improved cordycepin production. Using these culture conditions, a maximum production of cordycepin was 2008.48 mg/L for 700 mL working volume in the 1000 mL glass jars and total content of cordycepin reached 1405.94 mg/bottle. This method provides an effective way for increasing the cordycepin production at a large scale. The strategies used in this study could have a wide application in other fermentation processes. PMID:25054182

  16. Thalidomide inhibits UVB-induced mouse keratinocyte apoptosis by both TNF-α-dependent and TNF-α-independent pathways

    NARCIS (Netherlands)

    Lu, K.Q.; Brenneman, S.; Burns Jr., R.; Vink, A.; Gaines, E.; Haake, A.; Gaspari, A.

    2003-01-01

    Background: Thalidomide is an anti-inflammatory pharmacologic agent that has been utilized as a therapy for a number of dermatologic diseases. Its anti-inflammatory properties have been attributed to its ability to antagonize tumor necrosis factor-alfa (TNF-α) production by monocytes. However, its m

  17. The Protective Effect of Cordycepin On Alcohol-Induced Osteonecrosis of the Femoral Head

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    Yi-Xuan Chen

    2017-08-01

    Full Text Available Background: Alcohol abuse is known to be a leading risk factor for atraumatic osteonecrosis of the femoral head (ONFH, in which the suppression of osteogenesis plays a critical role. Cordycepin benefits bone metabolism; however, there has been no study to determine its effect on osteonecrosis. Methods: Human bone mesenchymal stem cells (hBMSCs were identified by multi-lineage differentiation. Alkaline phosphatase (ALP activity, RT-PCR, western blots, immunofluorescent assay and Alizarin red staining of BMSCs were evaluated. A rat model of alcohol-induced ONFH was established to investigate the protective role of cordycepin against ethanol. Hematoxylin & eosin (H&E staining and micro-computerized tomography (micro-CT were performed to observe ONFH. Apoptosis was assessed by TdT-mediated dUTP nick end labeling (TUNEL. Immunohistochemical staining was carried out to detect OCN and COL1. Results: Ethanol significantly suppressed ALP activity, decreased gene expression of OCN and BMP2, lowered levels of RUNX2 protein, and reduced immunofluorescence staining of OCN and COL1 and calcium formation of hBMSCs. However, these inhibitory effects were attenuated by cordycepin co-treatment at concentrations of 1 and 10 µg/mL Moreover, it was revealed that the osteo-protective effect of cordycepin was associated with modulation of the Wnt/β-catenin pathway. In vivo, by micro-CT, TUNEL and immunohistochemical staining of OCN and COL1, we found that cordycepin administration prevented alcohol-induced ONFH. Conclusion: Cordycepin treatment to enhance osteogenesis may be considered a potential therapeutic approach to prevent the development of alcohol-induced ONFH.

  18. Two-Step Purification of Cordycepin from Cordyceps Millitaris by High-Speed Countercurrent Chromatography

    Science.gov (United States)

    Ju, Xiuyun; Sun, Yong; Cao, Xiaoying; Jiang, Jihong; Zhang, Tianyou; Ito, Yoichiro

    2009-01-01

    Cordycepin is successfully isolated and purified from Cordyceps millitaris in two-step purification by high-speed countercurrent chromatography. Two solvent systems, ethyl acetate–1-butanol–water (3:2:5, v/v/v) and trichloromethane–methanol–1-butanol–water (2:1:0.25:1, v/v/v/v), were used for the two-step purification. The purity of the prepared cordycepin was 98.1% according to the high-performance liquid chromatography analysis. PMID:20046921

  19. Cordycepin Decreases Compound Action Potential Conduction of Frog Sciatic Nerve In Vitro Involving Ca2+-Dependent Mechanisms

    Directory of Open Access Journals (Sweden)

    Li-Hua Yao

    2015-01-01

    Full Text Available Cordycepin has been widely used in oriental countries to maintain health and improve physical performance. Compound nerve action potential (CNAP, which is critical in signal conduction in the peripheral nervous system, is necessary to regulate physical performance, including motor system physiological and pathological processes. Therefore, regulatory effects of cordycepin on CNAP conduction should be elucidated. In this study, the conduction ability of CNAP in isolated frog sciatic nerves was investigated. Results revealed that cordycepin significantly decreased CNAP amplitude and conductive velocity in a reversible and concentration-dependent manner. At 50 mg/L cordycepin, CNAP amplitude and conductive velocity decreased by 62.18 ± 8.06% and 57.34% ± 6.14% compared with the control amplitude and conductive velocity, respectively. However, the depressive action of cordycepin on amplitude and conductive velocity was not observed in Ca2+-free medium or in the presence of Ca2+ channel blockers (CdCl2/LaCl3. Pretreatment with L-type Ca2+ channel antagonist (nifedipine/deltiazem also blocked cordycepin-induced responses; by contrast, T-type and P-type Ca2+ channel antagonists (Ni2+ failed to block such responses. Therefore, cordycepin decreased the conduction ability of CNAP in isolated frog sciatic nerves via L-type Ca2+ channel-dependent mechanism.

  20. Lemon balm extract (Melissa officinalis, L.) promotes melanogenesis and prevents UVB-induced oxidative stress and DNA damage in a skin cell model.

    Science.gov (United States)

    Pérez-Sánchez, Almudena; Barrajón-Catalán, Enrique; Herranz-López, María; Castillo, Julián; Micol, Vicente

    2016-11-01

    Solar ultraviolet (UV) radiation is one of the main causes of a variety of cutaneous disorders, including photoaging and skin cancer. Its UVB component (280-315nm) leads to oxidative stress and causes inflammation, DNA damage, p53 induction and lipid and protein oxidation. Recently, an increase in the use of plant polyphenols with antioxidant and anti-inflammatory properties has emerged to protect human skin against the deleterious effects of sunlight. This study evaluates the protective effects of lemon balm extract (LBE) (Melissa Officinalis, L) and its main phenolic compound rosmarinic acid (RA) against UVB-induced damage in human keratinocytes. The LBE composition was determined by HPLC analysis coupled to photodiode array detector and ion trap mass spectrometry with electrospray ionization (HPLC-DAD-ESI-IT-MS/MS). Cell survival, ROS generation and DNA damage were determined upon UVB irradiation in the presence of LBE. The melanogenic capacity of LBE was also determined. RA and salvianolic acid derivatives were the major compounds, but caffeic acid and luteolin glucuronide were also found in LBE. LBE and RA significantly increased the survival of human keratinocytes upon UVB radiation, but LBE showed a stronger effect. LBE significantly decreased UVB-induced intracellular ROS production. Moreover, LBE reduced UV-induced DNA damage and the DNA damage response (DDR), which were measured as DNA strand breaks in the comet assay and histone H2AX activation, respectively. Finally, LBE promoted melanogenesis in the cell model. These results suggest that LBE may be considered as a candidate for the development of oral/topical photoprotective ingredients against UVB-induced skin damage. Copyright © 2016 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  1. Optimization of Ultrasonic-Assisted Extraction of Cordycepin from Cordyceps militaris Using Orthogonal Experimental Design

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    Hsiu-Ju Wang

    2014-12-01

    Full Text Available This study reports on the optimization of the extraction conditions of cordycepin from Cordyceps militaris by using ultrasonication. For this purpose, the orthogonal experimental design was used to investigate the effects of factors on the ultrasonic-assisted extraction (UAE. Four factors: extraction time (min, ethanol concentration (%, extraction temperature (°C and extraction frequency (kHz, were studied. The results showed that the highest cordycepin yield of 7.04 mg/g (86.98% ± 0.23% was obtained with an extraction time of 60 min, ethanol concentration of 50%, extraction temperature of 65 °C and extraction frequency of 56 kHz. It was found that the cordycepin extraction yield increased with the effect of ultrasonication during the extraction process. Therefore, UAE can be used as an alternative to conventional immersion extraction with respect to the recovery of cordycepin from C. militaris, with the advantages of shorter extraction time and reduced solvent consumption.

  2. Simple and efficient isolation of cordycepin from culture broth of a Cordyceps militaris mutant.

    Science.gov (United States)

    Masuda, Mina; Hatashita, Masanori; Fujihara, Shinya; Suzuki, Yu; Sakurai, Akihiko

    2015-12-01

    Isolation of cordycepin from the culture broth of Cordyceps militaris mutant was investigated. Based on the solubility curve, three crystallizing processes, temperature shift (process I), pH shift (process II), and pH shift followed by temperature shift (process III) were carried out. Process III was the most promising method regarding both purity and yield.

  3. D1 protein turnover is involved in protection of Photosystem II against UV-B induced damage in the cyanobacterium Arthrospira (Spirulina) platensis.

    Science.gov (United States)

    Wu, Hongyan; Abasova, Leyla; Cheregi, Otilia; Deák, Zsuzsanna; Gao, Kunshan; Vass, Imre

    2011-01-01

    By using two strains of Arthrospira (Spirulina)platensis, an economically important filamentous cyanobacterium, we compared the impairment of PSII activity and loss of D1 protein content under UV-B radiation. Our study showed that UV-B radiation induced a gradual loss of the oxygen-evolving activity to about 56% after 180 min UV-B irradiation both in strains 439 and D-0083, which have been kept under indoor and an outdoor culturing conditions, respectively for a prolonged period of time. The loss of oxygen evolution was accelerated in both strains in the presence of lincomycin, an inhibitor of protein synthesis, and the amount of D1 protein showed a decrease comparable to that of oxygen evolution during the UV-B exposure. However, the UV-B induced loss of oxygen-evolving activity and D1 protein amount was largely prevented when A. platensis cells were exposed to UV-B irradiance supplemented with visible light. Comparison of the two strains also showed a smaller extent of D1 protein synthesis dependent PSII repair in the indoor strain. Our results show that turnover of the D1 protein is an important defense mechanism to counteract the UV-B induced damage of PSII in A. platensis, and also that visible light plays an important role in maintaining the function of PSII under simultaneous exposure to UV-B and visible light.

  4. Cordycepin-enriched WIB-801C from Cordyceps militaris improves functional recovery by attenuating blood-spinal cord barrier disruption after spinal cord injury.

    Science.gov (United States)

    Lee, Jee Youn; Choi, Hye Young; Baik, Hyung Hwan; Ju, Bong G; Kim, Won-Ki; Yune, Tae Young

    2017-05-05

    Cordyceps militaris is an ingredient of traditional Chinese medicine and have been widely used for inflammatory diseases and cancer. Cordycepin is one of the major bioactive components of Cordyceps militaris, and has been known to have anti-inflammatory and anti-oxidant effects. In the present study, we examined whether WIB-801C, a standardized and cordycepin-enriched extract of caterpillar fungus (Cordyceps militaris), would attenuate blood-spinal cord barrier (BSCB) disruption by inhibiting matrix metalloprotease (MMP)-9 activity, leading to improvement of functional outcomes after spinal cord injury (SCI). Male Sprague-Dawley rats were subjected to contusive SCI using a New York University (NYU) impactor, and WIB-801C (50mg/kg) was administered at 2h and 8h after injury orally and further treated once a day for indicated time points. BSCB disruption, MMP-9 activity, blood infiltration, inflammation, neuronal apoptosis, axonal loss, demyelination, and neurological deficit were evaluated. We found that WIB-801C significantly attenuated BSCB disruption by inhibiting MMP-9 expression and activation after injury. The infiltration of neutrophils at 1 d and macrophage at 5 d after SCI was also ameliorated by WIB-801C as compared with vehicle control. In addition, the expression of inflammatory cytokines and mediators such as Tnf-α, IL-1β, IL-6, Cox-2, and inos as well as chemokines such as Gro-α and Mip-2α was significantly inhibited by WIB-801C. Furthermore, WIB-801C inhibits p38MAPK activation and proNGF production in microglia after injury. These events eventually led to the inhibition of apoptotic cell death of neurons and oligodendrocytes, improved functional recovery and attenuated demyelination and axon loss after SCI. Our results suggest that WIB-801C can be used as a therapeutic agent after SCI by attenuating BSCB disruption followed inflammation. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  5. Cordycepin enhances cisplatin apoptotic effect through caspase/MAPK pathways in human head and neck tumor cells

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    Chen YH

    2013-07-01

    Full Text Available Ying-Hui Chen,1,2,* Jo-Yu Wang,3,* Bo-Syong Pan,3,4 Yi-Fen Mu,3 Meng-Shao Lai,3,4 Edmund Cheung So,5 Thian-Sze Wong,6 Bu-Miin Huang3,4 1Department of Anesthesia, Chi-Mei Medical Center, Liouying, 2Department of Nursing, Min-Hwei College of Health Care Management, 3Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, 4The Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, 5Department of Anesthesia, An Nan Hospital, China Medical University, Tainan, Taiwan; 6Department of Surgery, University of Hong Kong Medical Center, Faculty of Medicine, The University of Hong Kong, Hong Kong *Authors contributed equally to this work Purpose: The present study aims to investigate whether the combination treatment of cordycepin (an extracted pure compound from Cordyceps sinensis and cisplatin (a platinum-based chemotherapy drug has better apoptotic effect in head and neck squamous cell carcinoma (HNSCC. Methods: The apoptotic influences of cordycepin and/or cisplatin treatments to human OC3, OEC-M1, and FaDu HNSCC cells were investigated by morphological observations, viability assay, flow cytometry assay, and Western blotting methods. Results: Data showed that the cell death phenomenon increased as the dosage of cordycepin or cisplatin increased, and it appeared more in cordycepin plus cisplatin cotreatment among three cell lines. Cell survival rates significantly decreased as the dosage of cordycepin or cisplatin increased, and the better apoptotic effects were observed in cotreatment. Cell cycle analysis further demonstrated that percentages of subG1 cells in cordycepin or cisplatin treatments significantly increased, suggesting that cells underwent apoptosis, and cordycepin plus cisplatin induced many more subG1 cells. Furthermore, cordycepin or cisplatin induced caspase-8, caspase-9, caspase-3, and poly adenosine diphosphate-ribose polymerase protein cleavages, and stimulated c

  6. Separation of cordycepin from Cordyceps militaris fermentation supernatant using preparative HPLC and evaluation of its antibacterial activity as an NAD+-dependent DNA ligase inhibitor

    Science.gov (United States)

    Zhou, Xiaofeng; Cai, Guoqiang; He, Yi; Tong, Guotong

    2016-01-01

    Cordycepin exhibits various bio-activities, including anticancer, antibacterial, antiviral and immune regulation activities, and is a significant focus of research. However, the preparation of high-purity cordycepin remains challenging. Also, the molecular target with which cordycepin interacts to cause an antibacterial effect remains unknown. In the present study, cordycepin was prepared by preparative high-performance liquid chromatography (prep-HPLC) and the purity obtained was 99.6%, indicating that this technique may be useful for the large-scale isolation of cordycepin in the future. The results of computational molecular docking analysis indicated that the interaction energy between cordycepin and NAD+-dependent DNA ligase (LigA) was lower than that between cordycepin and other common antibacterial targets. The highly pure cordycepin obtained by prep-HPLC demonstrated inhibitory activity against LigA from various bacteria in vitro. In conclusion, cordycepin may be useful as a broad-spectrum antibiotic targeting LigA in various bacteria. PMID:27588098

  7. Equine sarcoids: Bovine Papillomavirus type 1 transformed fibroblasts are sensitive to cisplatin and UVB induced apoptosis and show aberrant expression of p53

    Directory of Open Access Journals (Sweden)

    Finlay Margaret

    2012-12-01

    Full Text Available Abstract Bovine papillomavirus type 1 infects not only cattle but also equids and is a causative factor in the pathogenesis of commonly occurring equine sarcoid tumours. Whilst treatment of sarcoids is notoriously difficult, cisplatin has been shown to be one of the most effective treatment strategies for sarcoids. In this study we show that in equine fibroblasts, BPV-1 sensitises cells to cisplatin-induced and UVB-induced apoptosis, a known cofactor for papillomavirus associated disease, however BPV-1 transformed fibroblasts show increased clonogenic survival, which may potentially limit the therapeutic effects of repeated cisplatin treatment. Furthermore we show that BPV-1 increases p53 expression in sarcoid cell lines and p53 expression can be either nuclear or cytoplasmic. The mechanism and clinical significance of increase/abnormal p53 expression remains to be established.

  8. CoQ10-containing eye drops prevent UVB-induced cornea cell damage and increase cornea wound healing by preserving mitochondrial function.

    Science.gov (United States)

    Mencucci, Rita; Favuzza, Eleonora; Boccalini, Carlotta; Lapucci, Andrea; Felici, Roberta; Resta, Francesco; Chiarugi, Alberto; Cavone, Leonardo

    2014-10-09

    We evaluated the potential protective effects of Coenzyme Q10 (CoQ10) on human corneal cells and rabbit eyes after ultraviolet B (UVB) exposure and a model of wound healing in rabbit eyes after corneal epithelium removal. Human corneal epithelium cells (HCE) were exposed to a source of UVB radiation (312 nM) in the presence of different CoQ10 concentrations or vehicle. The mitochondrial function and cell survival were evaluated by means of 3-(4,5-dimethylthiazole-2-yl)2,5-diphenyl-tetrazolium (MTT) reduction and lactic dehydrogenase (LDH) release. Furthermore, quantitation of oxygen consumption and mitochondrial membrane potential were conducted. In vivo rabbit models were adopted to evaluate the effect of CoQ10 on UVB-induced conjunctival vessel hyperemia and corneal recovery after ethanol induced corneal lesion. In UVB-exposed HCE cells, CoQ10 addition led to an increased survival rate and mitochondrial function. Furthermore, oxygen consumption was maintained at control levels and adenosine triphosphate (ATP) decline was completely prevented in the CoQ10-treated cells. Interestingly, in an in vivo model, CoQ10 was able dose-dependently to reduce UVB-induced vessel hyperemia. Finally, in a model of corneal epithelium removal, 12 hours from surgery, animals treated with CoQ10 showed a reduction of damaged area in respect to vehicle controls, which lasted until 48 hours. We demonstrated that CoQ10 reduces corneal damages after UVB exposure in vivo and in vitro by preserving mitochondrial function. Also, for the first time to our knowledge we showed that the administration of CoQ10 after corneal epithelium removal promotes corneal wound healing. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  9. Characterization of Newly Bred Cordyceps militaris Strains for Higher Production of Cordycepin through HPLC and URP-PCR Analysis.

    Science.gov (United States)

    Lee, Hyun-Hee; Kang, Naru; Park, Inmyoung; Park, Jungwook; Kim, Inyoung; Kim, Jieun; Kim, Namgyu; Lee, Jae-Yun; Seo, Young-Su

    2017-07-28

    Cordyceps militaris, a member of Ascomycota, a mushroom referred to as caterpillar Dongchung-ha-cho, is commercially valuable because of its high content of bioactive substances, including cordycepin, and its potential for artificial cultivation. Cordycepin (3'-deoxyadenosine) is highly associated with the pharmacological effects of C. militaris. C. militaris is heterothallic in that two mating-type loci, idiomorph MAT1-1 and MAT1-2, exist discretely in two different spores. In this study, nine C. militaris strains were mated with each other to prepare newly bred strains that produced a larger amount of cordycepin than the parent strains. Nine strains of C. militaris were identified by comparing the internal transcribed spacer sequence, and a total of 12 single spores were isolated from the nine strains of C. militaris. After the MAT idiomorph was confirmed by PCR, 36 mating combinations were performed with six single spores with MAT1-1 and the others with MAT1-2. Eight mating combinations were successfully mated, producing stroma with perithecia. Cordycepin content analysis of all strains by high-performance liquid chromatography revealed that the KASP4-bred strain produced the maximum cordycepin among all strains, regardless of the medium and stroma parts. Finally, universal rice primer-PCR was performed to demonstrate that the bred strains were genetically different from the parental strains and new C. militaris strains. These results may be related to the recombination of genes during mating. The newly produced strains can be used to meet the industrial demand for cordycepin. In addition, breeding through mating suggests the possibility of producing numerous cordycepin-producing C. militaris strains.

  10. Functional study of Cordyceps sinensis and cordycepin in male reproduction: A review

    Directory of Open Access Journals (Sweden)

    Yung-Chia Chen

    2017-01-01

    Full Text Available Cordyceps sinensis has various biological and pharmacological functions, and it has been claimed as a tonic supplement for sexual and reproductive dysfunctions for a long time in oriental society. In this article, the in vitro and in vivo effects of C. sinensis and cordycepin on mouse Leydig cell steroidogenesis are briefly described, the stimulatory mechanisms are summarized, and the recent findings related to the alternative substances regulating male reproductive functions are also discussed.

  11. Inhibition of mTOR by apigenin in UVB-irradiated keratinocytes: A new implication of skin cancer prevention

    Science.gov (United States)

    Ye, Boping; Pelling, Jill C.; Volpert, Olga V.; Tong, Xin

    2016-01-01

    Ultraviolet B (UVB) radiation is the major environmental risk factor for developing skin cancer, the most common cancer worldwide, which is characterized by a berrant activation of Akt/mTOR (mammalian target of rapamycin). Importantly, the link between UV irradiation and mTOR signaling has not been fully established. Apigenin is a naturally occurring flavonoid that has been shown to inhibit UV-induced skin cancer. Previously, we have demonstrated that apigenin activates AMP-activated protein kinase (AMPK), which leads to suppression of basal mTOR activity in cultured keratinocytes. Here, we demonstrated that apigenin inhibited UVB-induced mTOR activation, cell proliferation and cell cycle progression in mouse skin and in mouse epidermal keratinocytes. Interestingly, UVB induced mTOR signaling via PI3K/Akt pathway, however, the inhibition of UVB-induced mTOR signaling by apigenin was not Akt-dependent. Instead, it was driven by AMPK activation. In addition, mTOR inhibition by apigenin in keratinocytes enhanced autophagy, which was responsible, at least in part, for the decreased proliferation in keratinocytes. In contrast, apigenin did not alter UVB-induced apoptosis. Taken together, our results indicate the important role of mTOR inhibition in UVB protection by apigenin, and provide a new target and strategy for better prevention of UV-induced skin cancer. PMID:26876613

  12. Inhibition of mTOR by apigenin in UVB-irradiated keratinocytes: A new implication of skin cancer prevention.

    Science.gov (United States)

    Bridgeman, Bryan B; Wang, Pu; Ye, Boping; Pelling, Jill C; Volpert, Olga V; Tong, Xin

    2016-05-01

    Ultraviolet B (UVB) radiation is the major environmental risk factor for developing skin cancer, the most common cancer worldwide, which is characterized by aberrant activation of Akt/mTOR (mammalian target of rapamycin). Importantly, the link between UV irradiation and mTOR signaling has not been fully established. Apigenin is a naturally occurring flavonoid that has been shown to inhibit UV-induced skin cancer. Previously, we have demonstrated that apigenin activates AMP-activated protein kinase (AMPK), which leads to suppression of basal mTOR activity in cultured keratinocytes. Here, we demonstrated that apigenin inhibited UVB-induced mTOR activation, cell proliferation and cell cycle progression in mouse skin and in mouse epidermal keratinocytes. Interestingly, UVB induced mTOR signaling via PI3K/Akt pathway, however, the inhibition of UVB-induced mTOR signaling by apigenin was not Akt-dependent. Instead, it was driven by AMPK activation. In addition, mTOR inhibition by apigenin in keratinocytes enhanced autophagy, which was responsible, at least in part, for the decreased proliferation in keratinocytes. In contrast, apigenin did not alter UVB-induced apoptosis. Taken together, our results indicate the important role of mTOR inhibition in UVB protection by apigenin, and provide a new target and strategy for better prevention of UV-induced skin cancer.

  13. Preparative separation of high-purity cordycepin from Cordyceps militaris(L.) Link by high-speed countercurrent chromatography

    Science.gov (United States)

    Zhu, Licai; Liang, Yong; Lao, Deqiang; Zhang, Tianyou; Ito, Yoichiro

    2009-01-01

    A high-speed counter-current chromatography (HSCCC) technique in a preparative scale has been applied to separate and purify cordycepin from the extract of Cordyceps militaris(L.) Link by a one-step separation. A high efficiency of HSCCC separation was achieved on a two-phase solvent system of n-hexane–n-butanol–methanol–water (23:80:30:155, v/v/v/v) by eluting the lower mobile phase at a flow rate of 2 ml/min under a revolution speed of 850 rpm. HSCCC separation of 216.2 mg crude sample (contained cordycepin at 44.7% purity after 732 cation-exchange resin clean-up) yielded 64.8 mg cordycepin with purity of 98.9% and 91.7% recovery. Identification of the target compound was performed by UV, IR, MS, 1H NMR and 13C NMR. PMID:21643461

  14. 蓝光诱导蛹虫草虫草素含量和分生孢子数的变化%Changes of Cordycepin Content and Conidia Amount of Cordyceps militaris by Blue Light Induction

    Institute of Scientific and Technical Information of China (English)

    金华燕; 沈俊良; 付鸣佳; 高雅; 黄妮娜

    2013-01-01

    [目的]研究蓝光对蛹虫草菌丝体中虫草素含量和分生孢子量的影响.[方法]以蛹虫草为材料,在不同的蓝光照射时间取样,以检测菌丝体中虫草素的含量,并计数蛹虫草分生孢子的产生量.[结果]蛹虫草受蓝光照射后,其虫草素的产生受到了一定的抑制,同时虫草素含量的变化也有一定的波动性;在相同的时间点,受蓝光照射的蛹虫草分生孢子数量比黑暗时的分生孢子数量要多,同时在一定时间范围内分生孢子数均呈上升趋势.[结论]该研究为系统性的研究蓝光对蛹虫草的影响奠定了基础.%[Objective]The aim was to study the effects of blue light on cordycepin content and conidia amount of Cordyceps militaris mycelium. [Method] The cordycepin content of mycelium and amount of Cordyceps milUaris conidia was detected at different blue light irradiation times by using Cordyceps militaris as materials. [ Result] The production of cordycepin was inhibited to a certain degree and the changes of cordycepin content also had a certain fluctuation after the Cordyceps militaris was irradiated by blue light; the amount of conidia of Cordyceps militaris irradiated by blue light was more than its number in the darkness at the same sampling time, and the number of conidia had been on an upward trend during a definite period of time at the same time. [Conclusion] This study provided foundation for the system researches on the effects of blue light on Cordyceps milUaris.

  15. Functional study of Cordyceps sinensis and cordycepin in male reproduction: A review.

    Science.gov (United States)

    Chen, Yung-Chia; Chen, Ying-Hui; Pan, Bo-Syong; Chang, Ming-Min; Huang, Bu-Miin

    2017-01-01

    Cordyceps sinensis has various biological and pharmacological functions, and it has been claimed as a tonic supplement for sexual and reproductive dysfunctions for a long time in oriental society. In this article, the in vitro and in vivo effects of C. sinensis and cordycepin on mouse Leydig cell steroidogenesis are briefly described, the stimulatory mechanisms are summarized, and the recent findings related to the alternative substances regulating male reproductive functions are also discussed. Copyright © 2016. Published by Elsevier B.V.

  16. UV-B Induced Generation of Reactive Oxygen Species Promotes Formation of BFA-Induced Compartments in Cells of Arabidopsis Root Apices.

    Science.gov (United States)

    Yokawa, Ken; Kagenishi, Tomoko; Baluška, František

    2015-01-01

    UV-B radiation is an important part of the electromagnetic spectrum emitted by the sun. For much of the period of biological evolution organisms have been exposed to UV radiation, and have developed diverse mechanisms to cope with this potential stress factor. Roots are usually shielded from exposure to UV by the surrounding soil, but may nevertheless be exposed to high energy radiation on the soil surface. Due to their high sensitivity to UV-B radiation, plant roots need to respond rapidly in order to minimize exposure on the surface. In addition to root gravitropism, effective light perception by roots has recently been discovered to be essential for triggering negative root phototropism in Arabidopsis. However, it is not fully understood how UV-B affects root growth and phototropism. Here, we report that UV-B induces rapid generation of reactive oxygen species which in turn promotes the formation of BFA-induced compartments in the Arabidopsis root apex. During unilateral UV-B irradiation of roots changes in auxin concentration on the illuminated side have been recorded. In conclusion, UV-B-induced and ROS-mediated stimulation of vesicle recycling promotes root growth and induces negative phototropism.

  17. UV-B induced generation of reactive oxygen species promotes formation of BFA-induced compartments in cells of Arabidopsis root apices

    Directory of Open Access Journals (Sweden)

    Ken eYokawa

    2016-01-01

    Full Text Available UV-B radiation is an important part of the electromagnetic spectrum emitted by the sun. For much of the period of biological evolution organisms have been exposed to UV radiation, and have developed diverse mechanisms to cope with this potential stress factor. Roots are usually shielded from exposure to UV by the surrounding soil, but may nevertheless be exposed to high energy radiationon the soil surface. Due to their high sensitivity to UV-B radiation, plant roots need to respond rapidly in order to minimize exposure on the surface. In addition to root gravitropism, effective light perception by roots has recently been discovered to be essential for triggering negative root phototropism in Arabidopsis. However, it is not fully understood how UV-B affects root growth and phototropism. Here, we report that UV-B induces rapid generation of reactive oxygen species which in turn promotes the formation of BFA-induced compartments in the Arabidopsis root apex. During unilateral UV-B irradiation of roots changes in auxin concentration on the illuminated side have been recorded. In conclusion, UV-B-induced and ROS-mediated stimulation of vesicle recycling promotes root growth and induces negative phototropism.

  18. Additive effect of heat on the UVB-induced tyrosinase activation and melanogenesis via ERK/p38/MITF pathway in human epidermal melanocytes.

    Science.gov (United States)

    Gu, Wei-Jie; Ma, Hui-Jun; Zhao, Guang; Yuan, Xiao-Ying; Zhang, Ping; Liu, Wen; Ma, Li-Juan; Lei, Xiao-Bing

    2014-08-01

    Heat is known as an environmental factor that causes significant skin pigmentation, but its effects on melanogenesis have been poorly studied. It has been shown that mitogen-activated protein kinase (MAPK) is involved in ultraviolet B (UVB) and stress-induced melanogenesis in melanocytes. In this study, we investigated the effects of heat and UVB, on melanocyte melanogenesis, differentiation, and MAPK phosphorylation. The results showed that heat (1 h at 40 °C for 5 days) increased cell dendrites, enlarged cell bodies, and induced extracellular signal-regulated kinases (ERK)/p38/MITF activation but did not influence melanogenesis of human epidermal melanocytes from skin phototype III. UVB irradiation (20 mJ/cm(2) for 5 days) induced melanogenesis and c-jun N-terminal kinases (JNK)/p38/MITF/tyrosinase activation in melanocytes from skin phototype III. UVB combined with heat resulted in much more significant tyrosinase activation and melanogenesis as compared with UVB alone in melanocytes from skin phototype III. Furthermore, heat treatment and UVB irradiation induced JNK, ERK, and p38 activation but not melanogenic and morphological changes in melanocytes from skin phototype I. These findings suggested that heat promoted melanocyte differentiation, probably via heat-induced ERK/p38/MITF/activation. Furthermore, heat had an additive effect on the UVB-induced tyrosinase activation and melanogenesis. These results provide a new clue for dermatologists for the treatment of hypopigmented skin disease with heat combined with UVB irradiation.

  19. Human papillomavirus types detected in skin warts and cancer differ in their transforming properties but commonly counteract UVB induced protective responses in human keratinocytes.

    Science.gov (United States)

    Shterzer, Naama; Heyman, Dariya; Shapiro, Beny; Yaniv, Abraham; Jackman, Anna; Serour, Francis; Chaouat, Malka; Gonen, Pinhas; Tommasino, Massimo; Sherman, Levana

    2014-11-01

    In the present study, E6E7 and E6 proteins of human papillomaviruses (HPVs) associated with skin warts and cancer were compared for their transforming and carcinogenic abilities in primary human keratinocytes (PHKs). We show that E6E7 of cancer associated beta HPV types, notably 49 and 24, were able to extend the life span and enhance the clonogenic efficiency of PHKs when maintained in serum free/low calcium medium. Activities of the beta HPV E6E7 were lower than those of HPV16 E6E7. In contrast, E6 proteins from HPV types detected in skin warts or cancer, notably 10, 49 and 38, attenuated UVB induced protective responses in PHKs including cell death, proliferation arrest and accumulation of the proapoptotic proteins, p53, bax or bak. Together, this investigation revealed functional differences and commonalities between HPVs associated with skin warts and cancer, and allowed the identification of specific properties of beta HPVs supporting their involvement in skin carcinogenesis.

  20. 虫草籼米复合米的研制%Preparation of restructuring indica rice with cordycepin

    Institute of Scientific and Technical Information of China (English)

    刘方; 程薇; 聂婷婷; 沈汪洋; 姚娣; 晏梦婷; 贾喜午; 陈轩; 周坚; 高虹

    2015-01-01

    以籼米为主要原料,辅以虫草培养基,通过双螺杆挤压技术制备富含虫草素的籼米复合米。选取虫草培养基添加量、水分、套筒温度、螺杆转速四个技术参数为主要因素,研究制备糊化度较低的富含虫草素的籼米复合米(简称虫草复合米)的最佳工艺参数。结果表明,虫草培养基添加量35%、水分40%、套筒温度100℃、螺杆转速250 r/min时,虫草复合米的品质指标较好,其蛋白质、脂肪以及虫草素含量明显高于原籼米。%ABSTRACT:With indica rice as the main raw material ,supplemented with cordyceps culture ,complex indica rice rich in cordycepin was prepared by a twin‐screw .Selecting the cordyceps culture medium content ,moisture content ,barrel tempera‐ture and screw speed as the main factor ,the complex cordycepin indica rice ( called cordycepin indica meters ) with low degree of pasting were obtained .The optimal parameters were as :cordyceps culture media content 35% ,moisture content 40% ,bar‐rel temperature 100℃ and screw speed 250 r/min .Under the conditions ,the quality of restructuring indica rice with cordycepin was good ,and the test data of protein ,fat and cordycepin content were significantly higher than that of the indica rice .

  1. Protective effects of sodium-L-ascorbyl-2 phosphate on the development of UVB-induced damage in cultured mouse skin.

    Science.gov (United States)

    Nayama, S; Takehana, M; Kanke, M; Itoh, S; Ogata, E; Kobayashi, S

    1999-12-01

    The protective effect of sodium-L-ascorbyl-2 phosphate (As-2P), a stable form of ascorbic acid (AsA), against photodamage induced by a single dose of UVB exposure (290-320 nm, Max 312 nm) was investigated using cultured mouse skin. When the cultured skin was treated with various As-2P concentrations, the cutaneous AsA level increased in proportion to the As-2P concentration. After 3 h of incubation, the AsA level in the cultured skin treated with 2, 20 and 100 mM As-2P increased 1.03-, 2.17- and 6.27-fold, respectively, compared with that of the control skin. These results suggest that As-2P was transported into the cultured mouse skin where it was converted to AsA. After 3 h, the cutaneous AsA level in irradiated (20 kJ/m2) skin was depleted to a half of that in the control skin. However, the level in skin pretreated with 20 mM As-2P was maintained within normal limits, even after 24 h. Pretreatment with 20 mM As-2P significantly prevented such photodamage as sunburn cell formation, DNA fragmentation and lipid peroxidation, which were caused by a single dose of UVB irradiation. These results suggest that the protective effect of 20 mM As-2P on UVB-induced cutaneous damage is due to the maintenance of a normal As level by conversion of As-2P to As in skin tissue.

  2. Thymol and Thymus Vulgaris L. activity against UVA- and UVB-induced damage in NCTC 2544 cell line.

    Science.gov (United States)

    Calò, Rossella; Visone, Clementina M; Marabini, Laura

    2015-09-01

    Many authors focused on the research of natural compounds in order to protect skin from indirect (UVA) and direct (UVB) ultraviolet radiation side effects. The aim of this study to evaluate the protective effect of a dry extract from T. vulgaris L. and of its major synthetic compound thymol (about 60%), against oxidative and genotoxic UVA- and UVB damage. Experiments were reproduced in a low differentiated keratinocytes cell line (NCTC 2544) Cells were pretreated for 1h, in serum-free medium, with thymol (1μg/mL) or T. vulgaris L. (1.82μg/mL) then exposed to different UVA (8-24J/cm(2)) or UVB doses (0.016-0.72J/cm(2)). Immediately after the UV exposure the intracellular redox status was evaluated by ROS quantification and by LPO. Genotoxic aspects were evaluated 24h after the end of irradiations using the alkaline comet assay, the micronucleus formation assay and the immunostaining of phosphorylated H2AX histone protein (detected 1h after the end of UV exposure). Thymol and T. vulgaris L. extract inhibited ROS generation in UVA and UVB-irradiated cells. On the contrary, MDA formation was reduced only in UVA treated cells. Both agents decreased the DNA damage evaluated by the alkaline comet assay, but not in the micronucleus and H2AX tests probably because of the severity of damage (double strands) detected.

  3. Resistance to UV-B induced DNA damage in extreme-tolerant cryptoendolithic Antarctic fungi: detection by PCR assays.

    Science.gov (United States)

    Selbmann, Laura; Isola, Daniela; Zucconi, Laura; Onofri, Silvano

    2011-10-01

    Cryptoendolithic Antarctic black fungi are adapted to the harshest terrestrial conditions as in the ice-free area of the McMurdo Dry Valleys. Recently, surviving space simulated conditions proves their bewildering extremotolerance. In order to investigate the potential DNA damage and their response after UV-B exposition, two strains of Antarctic cryptoendolithic black fungi, Cryomyces antarcticus CCFEE 534 and Cryomyces minteri CCFEE 5187, were irradiated at different UV-B doses. Since conventional methods cannot be applied to these organisms, the effect on the genome was assessed by RAPD and rDNA amplification PCR based assays; the results were compared with the responses of Saccharomyces pastorianus DBVPG 6283 treated with the same conditions. Results showed that template activity was drastically inhibited in S. pastorianus after irradiation. Dramatic changes in the RAPD profiles showed after 30 min of exposure while the rDNA amplification of SSU, LSU, and ITS portions failed after 30, 60, and 90 min of exposure respectively. No alteration was detected in the templates of the Antarctic strains where both RAPD profiles and rDNA PCR amplifications were unaffected even after 240 min of exposure. The electroferograms of the rDNA portions of Cryomyces strains were perfectly readable and conserved whilst the analyses revealed a marked alteration in S. pastorianus confirming the high resistance of the Antarctic strains to UV-B exposure.

  4. 蛹虫草提取物虫草素(3'-脱氧腺苷)对于高脂血症地鼠和大鼠的降血脂作用研究%Lipid-lowering effect of cordycepin (3'-deoxyadenosine) from Cordyceps militaris on hyperlipidemic hamsters and rats

    Institute of Scientific and Technical Information of China (English)

    高健; 连泽勤; 朱平; 朱海波

    2011-01-01

    3'-Deoxyadenosine, so-called cordycepin, is a bioactive component of the fungus Cordyceps militaris. It has been known to exhibit multiple-biological effects including: modulation of immune response, inhibition of tumor growth, hypotensive and vasorelaxation activities, and promoting secretion of adrenal hormone. To investigate its lipid-lowering effect, hyperlipidemic hamsters and rats fed by high-fat diet were both administered orally with cordycepin extracted from Cordyceps militaris for four weeks. The levels of lipids in hamsters and rats were measured enzymatically before and after the administration of cordycepin (12.5, 25 and 50 mg·kg-1). The results suggested that levels of serum total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C) and very low density lipoprotein cholesterol (VLDL-C) increased markedly in the two animal models by feeding high-fat diet. Meanwhile, cordycepin reduced levels of serum TC, TG, LDL-C, VLDL-C as well as LDL-C/HDL-C (high density lipoprotein cholesterol) and TC/HDL-C ratios. In concert with these effects, an increase in lipoprotein lipase (LPL) and hepatic lipase (HL) activity afforded by cordycepin was considered to contribute to the regulation on lipid profiles. Furthermore, no toxicity of cordycepin was observed by intragastric administration at the maximal tolerant dose in ICR mice for 14 days. The exact lipid-lowering effect of cordycepin needs further investigation.%3'-脱氧腺苷(又名虫草素)是从蛹虫草子实体中分离得到的一个具有生物活性的化合物.研究发现,虫草素具有多种生物效应,包括:调节免疫应答,抑制肿瘤生长,降压和舒张血管,促进肾上腺激素的分泌等.为研究其降血脂作用,本研究选用高脂饲料诱导的高脂血症金黄地鼠和大鼠,每天灌胃给予虫草素(12.5,25和50 mg·kg-1)共4周.在给药前及给药4周后,通过酶学方法测定地鼠和大鼠的血脂水平.结果显示,在饲喂高脂饲

  5. Characterizations of a new Cordyceps cicadae isolate and production of adenosine and cordycepin

    Directory of Open Access Journals (Sweden)

    Yongjun Wang

    2012-06-01

    Full Text Available Cordyceps is a fastidious pathogenic fungus infecting insects, and recent years have witnessed rapid progress in its medical properties. In this study, a wild isolate, C. cicadae MP12, was characterized through in vitro cultivation and its nuclear small-subunit (SSU ribosomal DNA (rDNA data. In vitro culture of C. cicadae MP12 was established by growing its fruiting bodies in a solid matrix. C. cicadae MP12 was inoculated into Cryptotympana atrata cicada pupae for in vivo culture, where the fungi developed its fruiting body as well. The contents of adenosine and cordycepin in dried fruiting bodies after culture were 1421.45µg/g and 1398.12 µg/g, respectively. Therefore, the established cultures from this study could be used for the production of various medically important metabolic substances.

  6. Characterizations of a new Cordyceps cicadae isolate and production of adenosine and cordycepin

    Science.gov (United States)

    Wang, Yongjun; Guo, Yanbin; Zhang, Liqin; Wu, Jia

    2012-01-01

    Cordyceps is a fastidious pathogenic fungus infecting insects, and recent years have witnessed rapid progress in its medical properties. In this study, a wild isolate, C. cicadae MP12, was characterized through in vitro cultivation and its nuclear small-subunit (SSU) ribosomal DNA (rDNA) data. In vitro culture of C. cicadae MP12 was established by growing its fruiting bodies in a solid matrix. C. cicadae MP12 was inoculated into Cryptotympana atrata cicada pupae for in vivo culture, where the fungi developed its fruiting body as well. The contents of adenosine and cordycepin in dried fruiting bodies after culture were 1421.45μg/g and 1398.12 μg/g, respectively. Therefore, the established cultures from this study could be used for the production of various medically important metabolic substances. PMID:24031851

  7. Identification of the Genes Involved in the Fruiting Body Production and Cordycepin Formation of Cordyceps militaris Fungus

    Science.gov (United States)

    Zheng, Zhuang-li; Qiu, Xue-hong

    2015-01-01

    A mutant library of Cordyceps militaris was constructed by improved Agrobacterium tumefaciens-mediated transformation and screened for degradation features. Six mutants with altered characters in in vitro and in vivo fruiting body production, and cordycepin formation were found to contain a single copy T-DNA. T-DNA flanking sequences of these mutants were identified by thermal asymmetric interlaced-PCR approach. ATP-dependent helicase, cytochrome oxidase subunit I and ubiquitin-like activating enzyme were involved in in vitro fruiting body production, serine/threonine phosphatase involved in in vivo fruiting body production, while glucose-methanol-choline oxidoreductase and telomerase reverse transcriptase involved in cordycepin formation. These genes were analyzed by bioinformatics methods, and their molecular function and biology process were speculated by Gene Ontology (GO) analysis. The results provided useful information for the control of culture degeneration in commercial production of C. militaris. PMID:25892913

  8. Protective effect of Calendula officinalis extract against UVB-induced oxidative stress in skin: evaluation of reduced glutathione levels and matrix metalloproteinase secretion.

    Science.gov (United States)

    Fonseca, Yris Maria; Catini, Carolina Dias; Vicentini, Fabiana T M C; Nomizo, Auro; Gerlach, Raquel Fernanda; Fonseca, Maria José Vieira

    2010-02-17

    Calendula officinalis flowers have long been employed time in folk therapy, and more than 35 properties have been attributed to decoctions and tinctures from the flowers. The main uses are as remedies for burns (including sunburns), bruises and cutaneous and internal inflammatory diseases of several origins. The recommended doses are a function both of the type and severity of the condition to be treated and the individual condition of each patient. Therefore, the present study investigated the potential use of Calendula officinalis extract to prevent UV irradiation-induced oxidative stress in skin. Firstly, the physico-chemical composition of marigold extract (ME) (hydroalcoholic extract) was assessed and the in vitro antioxidant efficacy was determined using different methodologies. Secondly, the cytotoxicity was evaluated in L929 and HepG2 cells with the MTT assay. Finally, the in vivo protective effect of ME against UVB-induced oxidative stress in the skin of hairless mice was evaluated by determining reduced glutathione (GSH) levels and monitoring the secretion/activity of metalloproteinases. The polyphenol, flavonoid, rutin and narcissin contents found in ME were 28.6 mg/g, 18.8 mg/g, 1.6 mg/g and 12.2mg/g, respectively and evaluation of the in vitro antioxidant activity demonstrated a dose-dependent effect of ME against different radicals. Cytoxicity experiments demonstrated that ME was not cytotoxic for L929 and HepG2 cells at concentrations less than or equal to of 15 mg/mL. However, concentrations greater than or equal to 30 mg/mL, toxic effects were observed. Finally, oral treatment of hairless mice with 150 and 300 mg/kg of ME maintained GSH levels close to non-irradiated control mice. In addition, this extract affects the activity/secretion of matrix metalloproteinases 2 and 9 (MMP-2 and -9) stimulated by exposure to UVB irradiation. However, additional studies are required to have a complete understanding of the protective effects of ME for skin

  9. Photoprotection by Punica granatum seed oil nanoemulsion entrapping polyphenol-rich ethyl acetate fraction against UVB-induced DNA damage in human keratinocyte (HaCaT) cell line.

    Science.gov (United States)

    Baccarin, Thaisa; Mitjans, Montserrat; Ramos, David; Lemos-Senna, Elenara; Vinardell, Maria Pilar

    2015-12-01

    There has been an increase in the use of botanicals as skin photoprotective agents. Pomegranate (Punica granatum L.) is well known for its high concentration of polyphenolic compounds and for its antioxidant and anti-inflammatory properties. The aim of this study was to analyze the photoprotection provided by P. granatum seed oil nanoemulsion entrapping the polyphenol-rich ethyl acetate fraction against UVB-induced DNA damage in the keratinocyte HaCaT cell line. For this purpose, HaCaT cells were pretreated for 1h with nanoemulsions in a serum-free medium and then irradiated with UVB (90-200 mJ/cm(2)) rays. Fluorescence microscopy analysis provided information about the cellular internalization of the nanodroplets. We also determined the in vitro SPF of the nanoemulsions and evaluated their phototoxicity using the 3T3 Neutral Red Uptake Phototoxicity Test. The nanoemulsions were able to protect the cells' DNA against UVB-induced damage in a concentration dependent manner. Nanodroplets were internalized by the cells but a higher proportion was detected along the cell membrane. The SPF obtained (~25) depended on the concentration of the ethyl acetate fraction and pomegranate seed oil in the nanoemulsion. The photoprotective formulations were classified as non-phototoxic. In conclusion, nanoemulsions entrapping the polyphenol-rich ethyl acetate fraction show potential for use as a sunscreen product.

  10. Pterocarpus santalinus L. Regulated Ultraviolet B Irradiation-induced Procollagen Reduction and Matrix Metalloproteinases Expression Through Activation of TGF-β/Smad and Inhibition of the MAPK/AP-1 Pathway in Normal Human Dermal Fibroblasts.

    Science.gov (United States)

    Gao, Wei; Lin, Pei; Hwang, Eunson; Wang, Yushuai; Yan, Zhengfei; Ngo, Hien T T; Yi, Tae-Hoo

    2017-08-31

    Ultraviolet light-induced reactive oxygen species (ROS) damage human skin and prematurely cause aging. A growing body of research is focusing on considering plants and plant-derived compounds as anti-photoaging therapeutic material. Pterocarpus santalinus L., as an Indian traditional medicine, possesses antidiabetic, anti-inflammatory and antioxidative effects. Here, we studied the anti-photoaging effects of ethanolic extract of P. santalinus L. heartwood (EPS) on ultraviolet radiation B (UVB)-irradiated normal human dermal fibroblasts (NHDFs). Results showed that EPS significantly inhibited the upregulation of matrix metalloproteinases and IL-6 caused by UVB irradiation, and suppressed UVB-induced phosphorylation of extracellular signal-regulated kinase, Jun N-terminal kinase, and p38, as well as the activation of AP-1 transcription factors. Further study indicated that UVB-induced production of MMP-1 and IL-6 could be inhibit by PD 98059 (an ERK inhibitor) and SP600125 (A JNK inhibitor), implied that EPS inhibited UVB-induced MMP-1 and IL-6 secretion by inactivating MAPK signaling pathway. In addition, EPS possessed an excellent antioxidant activity, which could increase cytoprotective antioxidants such as HO-1, NQ-O1 expression by facilitating the nuclear accumulation of Nrf2. Treatment of NHDFs with EPS also recovered UVB-induced procollagen type I reduction by activating TGF-β/Smad pathway. These findings demonstrated that EPS had a potential effect against UVB-induced skin photoaging. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  11. Effect of the salts of deep ocean water on the production of cordycepin and adenosine of Cordyceps militaris-fermented product.

    Science.gov (United States)

    Hung, Yu-Ping; Wang, Jyh-Jye; Wei, Bai-Luh; Lee, Chun-Lin

    2015-12-01

    Cordyceps militaris is a type of entomogenous fungi and has been widely used as a medicinal fungus in Asia. Cordycepin produced by C. militaris has also been found to protect the liver. Moreover, deep ocean water (DOW) was proven to increase the functional compounds of functional fungi-fermented products. However, the regulation of the metals in DOW is still unclear. Therefore, this study investigated the effect of DOW and certain major ions on the production of cordycepin and adenosine of C. militaris. The results indicated that, compared with using ultra-pure water (UPW), using DOW to cultivate C. militaris in a submerged culture increases the production of biomass and adenosine (p < 0.05). In the results of solid culture, the concentration of DOW exhibits a dose effect on cordycepin production. DOW contains ions that can improve the effectiveness of cordycepin, such as Mg(2+), Na(+), Ca(2+), Fe(2+), and NO3 (-), whereas the ion Cl(-) features an inhibitory effect. Moreover, Mg(2+), Na(+), K(+), Ca(2+), Fe(2+), and SO4 (2-)can increase the production of adenosine, whereas Cl(-) cannot. However, the synthetic water made from various types of sodium salts (MgCl2, NaCl, KCl, CaCl2, FeCl2) had nearly the same effect on cordycepin production as that of DOW.

  12. Beiwei ZHU%Optimization of Enzyme Extraction Conditions of Cordycepin Polysaccharide Using Response Surface Methodology

    Institute of Scientific and Technical Information of China (English)

    Dong AN; Beiwei ZHU

    2012-01-01

    [Objective] This study aimed to optimize extraction from the leftover of Cordyceps militaris the conditions for polysaccharide culture medium. [Method] Firstly the compositions of C. militaris culture medium were detected, before the cordycepin polysaccharide in medium was extracted using enzymatic hydrolysis. The optimum hydrolytic enzyme was selected through single factor test. Then, the extraction tem- perature, pH, enzyme content and solid-liquid ratio were optimized by response sur- face methodology, and confirmed by mathematical simulation. [Result] Acid hydrolytic enzyme was the optimum for extracting polysaccharides from the leftover of C. mili- taris culture medium. The optimum extraction conditions were as follows: extraction temperature 39.89 ℃, solid-liquid ratio 1:75.78, enzyme content 2.39% and pH 3.12. Under these conditions, the extraction rate of polysaccharides reached 9.96%. [Con- clusion] The study could provide a certain theoretical direction for extracting polysac- charities from the leftover of C. mliltaris culture medium on a large scale.

  13. A direct protein kinase B-targeted anti inflammatory activity of cordycepin from artificially cultured fruit body of Cordyceps militaris

    Directory of Open Access Journals (Sweden)

    Ju Young Yoon

    2015-01-01

    Full Text Available Background: Cordyceps militaris is one of well-known medicinal mushrooms with anti-inflammatory, anti-cancer, anti-diabetic, and anti-obesity activities. Objective: The objective of the following study is to isolate chemical components from the ethanol extract (Cm-EE from Cordyceps militaris and to evaluate their anti-inflammatory activities. Materials and Methods: Column chromatographic separation was performed and anti-inflammatory roles of these compounds were also examined by using NO production and protein kinase B (AKT activity assays. Results: From Cm-EE, 13 constituents, including trehalose (1, cordycepin (2, 6-hydroxyethyladenosine (3, nicotinic amide (4, butyric acid (5, β-dimorphecolic acid (6, α-dimorphecolic acid (7, palmitic acid (8, linoleic acid (9, cordycepeptide A (10, 4-(2-hydroxy-3-((9E,12E-octadeca-9,12-dienoyloxypropoxy-2-(trimethylammoniobutanoate (11, 4-(2-hydroxy-3-(palmitoyloxypropoxy-2-(trimethylammoniobutanoate (12, and linoleic acid methyl ester (13 were isolated. Of these components, compound 2 displayed a significant inhibitory effect on NO production in lipopolysaccharide (LPS-activated RAW264.7 cells. Furthermore, this compound strongly and directly suppressed the kinase activity of AKT, an essential signalling enzyme in LPS-induced NO production, by interacting with its ATP binding site. Conclusion: C. militaris could have anti-inflammatory activity mediated by cordycepin-induced suppression of AKT.

  14. Apoptosis of Corneal Epithelial Cells Caused by Ultraviolet B-induced Loss of K(+) is Inhibited by Ba(2.).

    Science.gov (United States)

    Glupker, Courtney D; Boersma, Peter M; Schotanus, Mark P; Haarsma, Loren D; Ubels, John L

    2016-07-01

    UVB exposure at ambient outdoor levels triggers rapid K(+) loss and apoptosis in human corneal limbal epithelial (HCLE) cells cultured in medium containing 5.5 mM K(+), but considerably less apoptosis occurs when the medium contains the high K(+) concentration that is present in tears (25 mM). Since Ba(2+) blocks several K(+) channels, we tested whether Ba(2+)-sensitive K(+) channels are responsible for some or all of the UVB-activated K(+) loss and subsequent activation of the caspase cascade and apoptosis. Corneal epithelial cells in culture were exposed to UVB at 80 or 150 mJ/cm(2). Patch-clamp recording was used to measure UVB-induced K(+) currents. Caspase-activity and TUNEL assays were performed on HCLE cells exposed to UVB followed by incubation in the presence or absence of Ba(2+). K(+) currents were activated in HCLE cells following UVB-exposure. These currents were reversibly blocked by 5 mM Ba(2+). When HCLE cells were incubated with 5 mM Ba(2+) after exposure to UVB, activation of caspases-9, -8, and -3 and DNA fragmentation were significantly decreased. The data confirm that UVB-induced K(+) current activation and loss of intracellular K(+) leads to activation of the caspase cascade and apoptosis. Extracellular Ba(2+) inhibits UVB-induced apoptosis by preventing loss of intracellular K(+) when K(+) channels are activated. Ba(2+) therefore has effects similar to elevated extracellular K(+) in protecting HCLE cells from UVB-induced apoptosis. This supports our overall hypothesis that elevated K(+) in tears contributes to protection of the corneal epithelium from adverse effects of ambient outdoor UVB.

  15. Narrowband UVB-induced lichen planus pemphigoides

    Directory of Open Access Journals (Sweden)

    Wai Man Mandy Chan

    2011-10-01

    Full Text Available Lichen planus pemphigoides (LPP is an autoimmune disease characterised by evolution of subepidermal blisters on normal and lichen planus affected skin. We describe a case of LPP in a 54-year-old Chinese woman. The patient presented with psoriasiform plaques and was diagnosed with guttate psoriasis. Narrowband ultraviolet B (NBUVB therapy was commenced, and she experienced a generalised eruption of violaceous papules, bullae over the lower limbs, and Wickham’s striae over the buccal mucosa. Histology from a plaque revealed interface dermatitis, while a specimen from a blister showed subepidermal bulla. Direct immunofluorescence showed linear deposition of IgG and C3 along the basement membrane. A diagnosis of LPP was made on clinicopathological grounds. This is the first case report of NBUVB alone in unmasking LPP. In this case report, we describe the pathological mechanism of NBUVB in the development of LPP and key features distinguishing LPP from bullous lupus erythematosus, bullous lichen planus, bullous pemphigoid, and psoriasis.

  16. The mechanism of CIRP in inhibition of keratinocytes growth arrest and apoptosis following low dose UVB radiation.

    Science.gov (United States)

    Liao, Yi; Feng, Jianguo; Zhang, Yi; Tang, Liling; Wu, Shiyong

    2017-06-01

    UV induces CIRP expression and subsequent Stat3 activation, but the biological function and mechanism of CIRP and Stat3 in mediating UVB-induced skin carcinogenesis have not been fully elucidated. In this study, we demonstrate that CIRP is elevated in all tested melanoma and non-melanoma skin cancer cell lines; and the expression of CIRP is upregulated in keratinocytes after being irradiated with relatively low dose (dose (50 mJ/cm(2) ), UVB acutely and chronically. The increased expression of CIRP, either induced by UVB or through overexpression, leads to resistance of keratinocytes to UVB-induced growth arrest and death; and reduced expression of CIRP by RNA knockdown sensitizes keratinocyte cells to the low dose UVB radiation. We also demonstrated that CIRP expression is required for the low dose UVB-induced Tyr705-phosphorylation, but not total amount, of Stat3. The p-Stat3 level is correlated with the expression levels of cyclin D1 and VEGF, two known downstream cell growth regulators of Stat3, as well as Bag-1/S, an apoptosis regulator. Inhibition of Stat3 DNA-binding activity by S3I-201 leads to a reduction of the p-Stat3 and Bag-1/S along with growth and survival of keratinocytes post-UVB; and the effect of S3I-201 on the UVB-irradiated cells can be partially inhibited by overexpression of CIRP or Bag-1/S. Furthermore, the overexpression of Bag-1/S can totally inhibit UVB-induced PARP cleavage and caspase 3 activation. The results presented above led us to propose that CIRP-p(705)Stat3 cascade promotes cell proliferation and survival post-UVB via upregulating the expression of cyclin D1 and Bag-1/S, respectively. Published 2017. This article is a U.S. Government work and is in the public domain in the USA. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  17. Extraction Protocol of Cordycepin from Cordyceps Wheat Medium%蛹虫草小麦培养基中虫草素提取工艺研究

    Institute of Scientific and Technical Information of China (English)

    谭琪明; 何珺; 文庭池; 康冀川

    2011-01-01

    To maximize the extraction efficiency of cordycepin from Cordyceps, the extraction procedure was optimized via modifying wheat medium including different extraction solution, rate of material to solvent, temperature , pH and time. The result revealed that the optimum extraction parameters were as follows: water as extraction solution, pH 5, ratio of material to liquid 1:50, 701, and 3 h, by which cordycepin might be extracted from Cordyceps conveniently and efficiently, and the extraction rate was as high as 94. 87% .%通过对比提取溶剂、料液比、温度、pH值及时间对提取蛹虫草小麦培养基中虫草素的影响,以确定虫草素提取最佳工艺参数.结果表明:最佳提取参数为水提取、pH值5,料液比1:50、温度70℃、时间3h.该方法从蛹虫草小麦培养基中提取虫草素,提取率可达94.87%.

  18. N-Phenethyl caffeamide and photodamage: protecting skin by inhibiting type I procollagen degradation and stimulating collagen synthesis.

    Science.gov (United States)

    Chiang, Hsiu-Mei; Chen, Chien-Wen; Lin, Tzu-Yu; Kuo, Yueh-Hsiung

    2014-10-01

    Skin is mainly damaged by genetic and environmental factors such as ultraviolet (UV) light and pollutants. UV light is a well-known factor that causes various types of skin damage and premature aging. Reactive oxygen species (ROS) are commonly involved in the pathogenesis of skin damage by activating the metalloproteinases that break down type I collagen. This study investigated the antioxidant and antiphotodamage activity and mechanisms of N-phenethyl caffeamide (K36) in human skin fibroblasts. The results indicated that K36 demonstrated strong 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) scavenging activity, which dose-dependently reduced the production of UVB-induced intracellular ROS in human dermal fibroblasts. K36 prevented UVB-irradiation-induced type I collagen degradation by inhibiting the expression of matrix metalloproteins-1, -3, and -9 and the phosphorylation of mitogen-activated protein (MAP) kinases. Furthermore, K36 elevated collagen synthesis in skin fibroblasts by inhibiting UVB-induced Smad7 overexpression. K36 downregulated the expression of the transcription factor, activator protein-1 (AP-1). Our results indicated that K36 exhibited antioxidant properties and prevented skin collagen degradation caused by UV exposure and the stimulation of collagen synthesis, which suggests the potential use of K36 in preventing photodamage.

  19. Higher Anti-Liver Fibrosis Effect of Cordyceps militaris-Fermented Product Cultured with Deep Ocean Water via Inhibiting Proinflammatory Factors and Fibrosis-Related Factors Expressions

    Directory of Open Access Journals (Sweden)

    Yu-Ping Hung

    2017-06-01

    Full Text Available Deep ocean water (DOW has been shown to enhance the functional components of fungi, resulting in increased health benefits. Therefore, using DOW for culturing fungi can enhance the cordycepin and adenosine of Cordyceps militaris (CM and its protective effects on the liver. In this study, the antiliver fibrosis effects and mechanisms of ultrapure water-cultured CM (UCM, DOW-cultured CM (DCM, synthetic water-cultured CM, DOW, cordycepin, and adenosine were compared in the liver fibrosis mice induced by intraperitoneal injections of thioacetamide (TAA. The results indicated that DCM exhibited superior performance in reducing liver collagen accumulation, mitigating liver injuries, inhibiting proinflammatory factors and fibrosis-related factor (TGF-β1, Smad2/3, α-SMA, COL1A1 expression compared with UCM. DOW, cordycepin, and adenosine also performed antiliver fibrosis effect. Therefore, because DCM is rich in DOW and functional components, it can achieve anti-liver fibrosis effects through multiple pathways. These ameliorative effects are considerably superior to those of UCM.

  20. Higher Anti-Liver Fibrosis Effect of Cordyceps militaris-Fermented Product Cultured with Deep Ocean Water via Inhibiting Proinflammatory Factors and Fibrosis-Related Factors Expressions.

    Science.gov (United States)

    Hung, Yu-Ping; Lee, Chun-Lin

    2017-06-08

    Deep ocean water (DOW) has been shown to enhance the functional components of fungi, resulting in increased health benefits. Therefore, using DOW for culturing fungi can enhance the cordycepin and adenosine of Cordyceps militaris (CM) and its protective effects on the liver. In this study, the antiliver fibrosis effects and mechanisms of ultrapure water-cultured CM (UCM), DOW-cultured CM (DCM), synthetic water-cultured CM, DOW, cordycepin, and adenosine were compared in the liver fibrosis mice induced by intraperitoneal injections of thioacetamide (TAA). The results indicated that DCM exhibited superior performance in reducing liver collagen accumulation, mitigating liver injuries, inhibiting proinflammatory factors and fibrosis-related factor (TGF-β1, Smad2/3, α-SMA, COL1A1) expression compared with UCM. DOW, cordycepin, and adenosine also performed antiliver fibrosis effect. Therefore, because DCM is rich in DOW and functional components, it can achieve anti-liver fibrosis effects through multiple pathways. These ameliorative effects are considerably superior to those of UCM.

  1. 冬虫夏草中甘露醇和虫草素的TOF-SIMS分析%TOF-SIMS Study of Mannitol and Cordycepin in Cordyceps Sinensis

    Institute of Scientific and Technical Information of China (English)

    李展平; 真田则明; 孙素琴

    2016-01-01

    Cordyceps sinensis is a well‐known traditional Chinese medicine ;it is also called DongChongXiaCao (winter worm summer grass) in Chinese .Mannitol and cordycepin ,the most important two pharmacological active components of cordyceps sinensis ,were studied with TOF‐SIMS .This Study was focused on the chemical information including 251 amu mass peak . Based on high mass resolution of TOF‐SIMS analysis ,the fragment ions of 251 and 252 amu detected in Cordyceps sinensis may not be the molecular ion M + and/or[M+ H]+ of cordycepin ,which ispossiblely the root cause of the argument in the study of cordycepin in published papers .It could be a basis for further study of cordycepin components of cordyceps sinensis in the fu‐ture .The 181amu mass peak of minus ion in mannitol was also studied in detail and was certified to be a reliable evidence of man‐nitol .This research shows that TOF‐SIMS has been proven as an effective method in the study of cordyceps sinensis .%用飞行时间二次离子质谱(TOF‐SIMS)分析研究了冬虫夏草中两个最重要的药效活性物质,甘露醇和虫草素,重点研究对应质量数251 amu的质谱峰含有的化学信息。利用TOF‐SIMS高质量分辨率的优势,检测并识别251和252 amu质谱峰的信号有可能不是保健药理活性物质虫草素C10 H13 N5 O3(251 amu)产生的分子离子峰M +,[M+ H]+,这或许就是文献中有关研究虫草素存在争论的原因。TOF‐SIMS分析结果为进一步解读251 am u质谱峰的化学内含、深入研究冬虫夏草中虫草素提供了依据;同时就甘露醇对应的(181 amu附近)TOF‐SIMS负离子质谱峰做了细致的解读,确认181 amu质谱峰是识别冬虫夏草中甘露醇的可靠依据。本研究证明,TOF‐SIMS是分析、研究、鉴别冬虫夏草的有效手段。

  2. Inhibition of Ultraviolet B-Induced Expression of the Proinflammatory Cytokines TNF-α and VEGF in the Cornea by Fucoxanthin Treatment in a Rat Model

    Directory of Open Access Journals (Sweden)

    Shiu-Jau Chen

    2016-01-01

    Full Text Available Ultraviolet B (UVB irradiation is the most common cause of radiation damage to the eyeball and is a risk factor for human corneal damage. We determined the protective effect of fucoxanthin, which is a carotenoid found in common edible seaweed, on ocular tissues against oxidative UVB-induced corneal injury. The experimental rats were intravenously injected with fucoxanthin at doses of 0.5, 5 mg/kg body weight/day or with a vehicle before UVB irradiation. Lissamine green for corneal surface staining showed that UVB irradiation caused serious damage on the corneal surface, including severe epithelial exfoliation and deteriorated epithelial smoothness. Histopathological lesion examination revealed that levels of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α and vascular endothelial growth factor (VEGF, significantly increased. However, pretreatment with fucoxanthin inhibited UVB radiation-induced corneal disorders including evident preservation of corneal surface smoothness, downregulation of proinflammatory cytokine expression, and decrease of infiltrated polymorphonuclear leukocytes from UVB-induced damage. Moreover, significant preservation of the epithelial integrity and inhibition of stromal swelling were also observed after UVB irradiation in fucoxanthin-treated groups. Pretreatment with fucoxanthin may protect against UVB radiation-induced corneal disorders by inhibiting expression of proinflammatory factors, TNF-α, and VEGF and by blocking polymorphonuclear leukocyte infiltration.

  3. Preparative isolation of cordycepin, N(6)-(2-hydroxyethyl)-adenosine and adenosine from Cordyceps militaris by macroporous resin and purification by recycling high-speed counter-current chromatography.

    Science.gov (United States)

    Zhang, Zhong; Tudi, Tuernisan; Liu, Yanfang; Zhou, Shuai; Feng, Na; Yang, Yan; Tang, Chuanhong; Tang, Qingjiu; Zhang, Jingsong

    2016-10-15

    In this study, cordycepin, N(6)-(2-hydroxyethyl)-adenosine (HEA) and adenosine from the fruiting bodies of Cordyceps militaris were separated by using macroporous resin NKA-II adsorption. The parameters of static adsorption were tested and the optimized conditions were as follow: the total adsorption time was 12h, 50% ethanol was used for desorption and the desorption time was 9h. The crude sample that was prepared by macroporous resin NKA-II contained 3.4% cordycepin, 3.7% HEA and 4.9% adenosine. Then the crude sample was further purified by recycling high-speed counter-current chromatography (HSCCC) with ethyl acetate, n-butanol, 1.5% aqueous ammonium hydroxide (1:4:5, v/v/v) as the optimized two-phase solvent system. Three nucleosides including 15.6mg of cordycepin, 16.9mg of HEA and 23.2mg of adenosine were obtained from 500mg of crude sample in one-step separation. The purities of three compounds were 98.5, 98.3 and 98.0%, respectively, as determined by high performance liquid chromatography. Copyright © 2016. Published by Elsevier B.V.

  4. Anti-wrinkle and anti-inflammatory effects of active garlic components and the inhibition of MMPs via NF-κB signaling.

    Directory of Open Access Journals (Sweden)

    So Ra Kim

    Full Text Available Skin aging is a multisystem degenerative process caused by several factors, such as, UV irradiation, stress, and smoke. Furthermore, wrinkle formation is a striking feature of photoaging and is associated with oxidative stress and inflammatory response. In the present study, we investigated whether caffeic acid, S-allyl cysteine, and uracil, which were isolated from garlic, modulate UVB-induced wrinkle formation and effect the expression of matrix-metalloproteinase (MMP and NF-κB signaling. The results obtained showed that all three compounds significantly inhibited the degradation of type І procollagen and the expressions of MMPs in vivo and attenuated the histological collagen fiber disorder and oxidative stress in vivo. Furthermore, caffeic acid and S-allyl cysteine were found to decrease oxidative stress and inflammation by modulating the activities of NF-κB and AP-1, and uracil exhibited an indirect anti-oxidant effect by suppressing cyclooxygenase-2 (COX-2 and inducible nitric oxide synthase (iNOS expressions levels and downregulating transcriptional factors. These results suggest that the anti-wrinkle effects of caffeic acid, S-allyl cysteine, and uracil are due to anti-oxidant and/or anti-inflammatory effects. Summarizing, caffeic acid, S-allyl cysteine, and uracil inhibited UVB-induced wrinkle formation by modulating MMP via NF-κB signaling.

  5. Blocking RhoA/ROCK inhibits the pathogenesis of pemphigus vulgaris by suppressing oxidative stress and apoptosis through TAK1/NOD2-mediated NF-κB pathway.

    Science.gov (United States)

    Liang, Junqin; Zeng, Xuewen; Halifu, Yilinuer; Chen, Wenjing; Hu, Fengxia; Wang, Peng; Zhang, Huan; Kang, Xiaojing

    2017-06-12

    Oxidative stress and apoptosis play critical roles in pemphigus vulgaris (PV). The main aim of the present study was to investigate the effects of RhoA/ROCK signaling on UVB-induced oxidative damage, and to delineate the molecular mechanisms involved in the UVB-mediated inflammatory and apoptotic response. In HaCaT cells, we observed that blockage of RhoA/ROCK signaling with the inhibitor CT04 or Y27632 greatly inhibited the UVB-mediated increase in intracellular reactive oxygen species (ROS). Additionally, inhibition of RhoA/ROCK signaling reduced UVB-induced apoptosis, as exemplified by a reduction in DNA fragmentation, and also elevated anti-apoptotic Bcl-2 protein, concomitant with reduced levels of pro-apoptotic protein Bax, caspase-3 cleavage and decreased PARP-1 protein. The release of inflammatory mediators TNF-α, IL-1β, and IL-6 was also attenuated. Mechanically, we observed that blockage of RhoA/ROCK repressed the TAK1/NOD2-mediated NF-κB pathway in HaCaT cells exposed to UVB. Taken together, these data reveal that RhoA/ROCK signaling is one of the regulators contributing to oxidative damage and apoptosis in human keratinocytes, suggesting that RhoA/ROCK signaling has strong potential to be used as a useful therapeutic target in skin diseases including PV.

  6. 蛹虫草高产胞外虫草素和虫草多糖的诱变育种%Enhanced production of extracellular cordycepin and polysaccharide in Cordyceps militaris by mutation breeding

    Institute of Scientific and Technical Information of China (English)

    孟泽彬; 文庭池; 康冀川; 康超; 王永江

    2012-01-01

    通过诱变获得高产胞外虫草素和虫草多糖的蛹虫草菌株.采用紫外线诱变(UV)、化学诱变(LiCl)、复合诱变(UV-LiCl) 3种方式对蛹虫草孢子进行诱变;发酵检测存活菌株的胞外虫草素和虫草多糖的含量.结果:以胞外虫草素为指标,3种诱变方式的最大正突变率分别为化学突变(29.2%)>紫外突变(28.6%)>复合诱变(26.5%);以胞外多糖为指标,最大正突变率分别为紫外诱变(35.7%)>复合诱变(33.3%)>化学诱变(27.0%).紫外诱变突变株Z-5-1胞外虫草素产量达0.842g/L,比出发菌株高311%;紫外诱变突变株Z-4-7胞外虫草多糖产量达5.250g/L,比出发菌株高148%.在连续培养5代后,仍具有较好的遗传稳定性.紫外诱变能获得较高的蛹虫草正突变率,同时能获得高产虫草素、虫草多糖的突变株.%The aim was to obtain high-yield strains of extracellular cordycepin and polysaccharide of Cordyceps mititaris. Three kind of mutation way, ultraviolet radiation (UV)、lithium chloride (LiCl) and compound mutagenesis (UV-LiCl) were used to deal with the spores of Cordyceps militaris. Fermenting the survival strains and detecting their content of extracellular cordycepin and cordyceps polysaccharide. The results showed: the maximum positive mutation rate order of extracellular cordycepin was LiCl (29.2%)>UV(28.6%)>UV-LiCl(26.5%) respectively, and that of extracellular polysaccharide was UV(35.7%)>UV-LiCl(33.3%)>LiCl(27.0%). The UV-induced mutant strain Z-5-1 had the highest extracellular cordycepin yield of 0.842g/L, which was 311% higher than that of the original strain. And the UV-induced mutant strain Z-4-7 had the highest extracellular Cordyceps polysaccharide production of 5.250g/L, which was 148% higher than that of the original strain. UV mutagenesis could obtain a higher positive mutation rate for Cordyceps militaris, while could produce good mutant strains with high-yield of extracellular cordycepin and

  7. 蛹虫草Cordyceps militaris JN168产虫草素液态发酵条件的优化%Optimization of Fermentation Conditions for Cordycepin by Cordyceps militaris JN168

    Institute of Scientific and Technical Information of China (English)

    岳翠翠; 沈健增; 蔡宇杰; 廖祥儒; 罗军侠; 张大兵

    2013-01-01

    利用单因素筛选和响应面法对蛹虫草Cordyceps militaris JN168产虫草素的液态发酵培养基进行优化,以确定蛹虫草产虫草素的最佳发酵培养基配方.结果表明,蛹虫草产虫草素的最佳碳源为葡萄糖,最适质量浓度为40 g/L;最佳氮源为牛肉膏,最适质量浓度15 g/L;加入的无机盐及其添加量分别为MgSO4 0.76 g/L,K2HPO4 0.63 g/L,CaCl2 0.66 g/L,Na2HPO4 0.67 g/L.优化后发酵液中虫草素质量浓度达到633.47 mg/L,是优化前的6倍.%The components for cordycepin production by Cordyceps militaris JN168 were optimized with single factor experiment and response surface methodology. The purpose of this study is to determine the best fermentation medium for cordycepin production by Cordyceps militaris JN168. Results showed that glucose and beef extract are the appropriate carbon and nitrogen sources with an optimal concentration of 40 g/L and 15 g/L, respectively. And adding inorganic salt is MgSO4, K2HPO4,CaCl2 and Na2HPO4 with an optimal concentration of 0.76 g/L,0.63 g/L,0.66 g/L and 0.67 g/L respectively. The cordycepin concentration in the fermentation broth after optimization is 633.47 mg/L, which is 6 times before the optimization.

  8. 辐射诱变高产虫草素蛹虫草菌株的研究%Study of High-yielding Cordycepin Strains of Cordyceps militaris by Radioactive Irradiation

    Institute of Scientific and Technical Information of China (English)

    张红; 于桂英; 徐方旭; 王升厚

    2011-01-01

    [Objective] The aim of the study was to screen high-yielding strains of Cordyceps militaris. [ Method ] A method of radioactive 6OC0-7 ray irradiation on the 9train of Cordyceps militaris were used. [ Result] yccGylO16 mutant strain were selected and the biological con version rate was 12. 5% , mycelia of Cordyceps militaris content reached 481. 6 mg/kg, sub-Entity cordycepin militaris content was 9 600 nig/kg, significantly higher than the original control strains. [Conclusion] After 10 generations PDA slant enrichment subculture medium and cans bottles wheat cultivation experiment, the mutant strain was better than the original with stable yield characters and strong ability of produ cing cordycepin.%[目的]筛选高产虫草素蛹虫草菌株.[方法]采用放射性元素60Co-γ射线辐射诱变方法对蛹虫草菌株进行处理.[结果]筛选出yccGy1016诱变菌株为目标菌株,其生物转化率达12.5%,菌丝中虫草素含量达481.6 mg/kg,子实体虫草素含量达9 600 mg/kg,明显高于对照菌株.[结论]经10代加富PDA斜面继代培养及罐头瓶小麦培养基栽培试验,yccGy1016诱变菌株具有产量性状稳定、产生虫草素能力强的特点.

  9. Thread Embedding Acupuncture Inhibits Ultraviolet B Irradiation-Induced Skin Photoaging in Hairless Mice

    Directory of Open Access Journals (Sweden)

    Yoon-Jung Kim

    2015-01-01

    Full Text Available Thread embedding acupuncture (TEA is an acupuncture treatment applied to many diseases in Korean medical clinics because of its therapeutic effects by continuous stimulation to tissues. It has recently been used to enhance facial skin appearance and antiaging, but data from evidence-based medicine are limited. To investigate whether TEA therapy can inhibit skin photoaging by ultraviolet B (UVB irradiation, we performed analyses for histology, histopathology, in situ zymography and western blot analysis in HR-1 hairless mice. TEA treatment resulted in decreased wrinkle formation and skin thickness (Epidermis; P=0.001 versus UV in UVB irradiated mice and also inhibited degradation of collagen fibers (P=0.010 versus normal by inhibiting proteolytic activity of gelatinase matrix-metalloproteinase-9 (MMP-9. Western blot data showed that activation of c-Jun N-terminal kinase (JNK induced by UVB (P=0.002 versus normal group was significantly inhibited by TEA treatment (P=0.005 versus UV with subsequent alleviation of MMP-9 activation (P=0.048 versus UV. These results suggest that TEA treatment can have anti-photoaging effects on UVB-induced skin damage by maintenance of collagen density through regulation of expression of MMP-9 and related JNK signaling. Therefore, TEA therapy may have potential roles as an alternative treatment for protection against skin damage from aging.

  10. UVB-induced immune suppression and infection with Schistosoma mansoni

    Energy Technology Data Exchange (ETDEWEB)

    Noonan, F.P.; Lewis, F.A. [George Washington Univ., Washington, DC (United States). School of Medicine]|[Biomedical Research Inst., Rockville, MD (United States)

    1995-01-01

    Irradiation with ultraviolet B (UVB, 290-320 nm) causes a systematic immunosuppression of cell-mediated immunity. The question of whether UV immunosuppression modulates the course of infectious diseases is important because UVB levels in sunlight are sufficient to predict significant UV-induced immunosuppression at most latitudes. We have investigated the effect of immunosuppressive doses of UVB on the disease caused by the helminth parasite Schistosoma mansoni. C57BL/6 mice were irradiated once or three times weekly over 60-80 days with UV from a bank of FS40 sunlamps. Each UV treatment consisted of an immunosuppressive UV dose, as determined by suppression of contact hypersensitivity to trinitrochlorobenzene, corresponding to about 15-30 min of noonday tropical sunlight exposure under ideal clear sky conditions. Cumulative UV doses were between 80 and 170 kJ/m{sup 2}. Worm and egg burdens, liver granuloma diameters and liver fibrosis showed minimal changes (< 20%) compared with parameters in unirradiated animals. Ultraviolet irradiation (a total of 55 kJ/m{sup 2} administered in six treatments) did not impair the resistance to rechallenge conferred by vaccination with {sup 60}Co-irradiated cercariae. We have observed a dichotomy between UV immnosuppression and both disease and vaccination in this helminth infection, in contrast to the effects of UVB shown in other infectious diseases. (author).

  11. C*HSDGIC* from cyclization of PACAP (1-5) attenuates UVB-induced apoptosis of human retinal pigment epithelial cells%小环肽C*HSDGIC*对中波紫外线诱导的视网膜色素人上皮细胞凋亡的影响

    Institute of Scientific and Technical Information of China (English)

    丁勇; 程欢欢; 余榕捷; 陈建苏

    2012-01-01

    the proliferation and anti - apoptosis of human RPE cells were achieved at the concentration of 100 μmol/L, which increased the viability by ( 34. 23 ± 3. 39) % and ( 20. 10 ± 1. 48 ) % , respectively. The percentage of apoptolic cells was decreased by (5. 63 ± 1.49) % with CHC treatmenl ( 100 μmol/L) after UVB irradiation,and the percentage of milochon-drium - depolarizing cells was decreased by (5.2 ±0. 5) % . CONCLUSION: PAC1 receptor exisls in human RPE cells. C * HSDGIC * increases the viability of RPE cells and atlenuates UVB - induced apoplosis.

  12. Dietary proanthocyanidins inhibit UV radiation-induced skin tumor development through functional activation of the immune system.

    Science.gov (United States)

    Katiyar, Santosh K

    2016-06-01

    The incidence of skin cancer is equivalent to the incidence of malignancies in all other organs combined. The main risk factor for this disease is overexposure of the skin to solar ultraviolet (UV) radiation. UV irradiation induces inflammation, oxidative stress, DNA damage, and suppression of the immune system in the skin, which together contribute to carcinogenesis. The use of dietary phytochemicals shows great promise as a complementary and alternative strategy for skin cancer prevention. Grape seed proanthocyanidins (GSPs) have been tested extensively for their anti-skin cancer effect using in vivo animal models. Supplementation of an AIN76A control diet with GSPs (0.2 and 0.5%, w/w) significantly inhibits UV radiation-induced skin tumor development as well as malignant transformation of papillomas to carcinoma in mice. The inhibition of UVB-induced skin tumor development by GSPs is mediated through interrelated mechanisms of action including: (i) inhibition of inflammation, (ii) rapid repair of damaged DNA, and (iii) stimulation of immune system. Additionally, the chemopreventive effects of GSPs involve DNA repair-dependent functional activation of antigen-presenting cells and stimulation of CD8(+) effector T cells. These effects of GSPs could be useful in attenuation of the adverse effects of UV radiation and may have health benefits in humans. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Inhibition of UVB-Induced Skin Cancer by Apigenin: a Review of Its Function and Underlying Mechanism%芹菜素(Apigenin)抗UVB引发的皮肤癌活性及其作用机制研究概况

    Institute of Scientific and Technical Information of China (English)

    王璞; 叶波平

    2015-01-01

    天然来源的黄酮类化合物芹菜素(Apigenin)具有抗氧化、抗炎以及抗癌作用,尤其针对UVB照射引发的皮肤癌,及芹菜素的抗癌作用机制,包括它能够激活AMPK,抑制PI3K/Akt/mTOR,引起细胞自噬,从而促进受损细胞凋亡,减少DNA损伤,最终达到抗UVB引起的皮肤癌的效果.

  14. Bystander effects in UV-induced genomic instability: Antioxidants inhibit delayed mutagenesis induced by ultraviolet A and B radiation

    Directory of Open Access Journals (Sweden)

    Dahle Jostein

    2005-01-01

    Full Text Available Abstract Background Genomic instability is characteristic of many types of human cancer. Recently, we reported that ultraviolet radiation induced elevated mutation rates and chromosomal instability for many cell generations after ultraviolet irradiation. The increased mutation rates of unstable cells may allow them to accumulate aberrations that subsequently lead to cancer. Ultraviolet A radiation, which primarily acts by oxidative stress, and ultraviolet B radiation, which initially acts by absorption in DNA and direct damage to DNA, both produced genomically unstable cell clones. In this study, we have determined the effect of antioxidants on induction of delayed mutations by ultraviolet radiation. Delayed mutations are indicative of genomic instability. Methods Delayed mutations in the hypoxanthine phosphoribosyl transferase (hprt gene were detected by incubating the cells in medium selectively killing hprt mutants for 8 days after irradiation, followed by a 5 day period in normal medium before determining mutation frequencies. Results The UVB-induced delayed hprt mutations were strongly inhibited by the antioxidants catalase, reduced glutathione and superoxide dismutase, while only reduced glutathione had a significant effect on UVA-induced delayed mutations. Treatment with antioxidants had only minor effects on early mutation frequenies, except that reduced glutathione decreased the UVB-induced early mutation frequency by 24 %. Incubation with reduced glutathione was shown to significantly increase the intracellular amount of reduced glutathione. Conclusion The strong effects of these antioxidants indicate that genomic instability, which is induced by the fundamentally different ultraviolet A and ultraviolet B radiation, is mediated by reactive oxygen species, including hydrogen peroxide and downstream products. However, cells take up neither catalase nor SOD, while incubation with glutathione resulted in increased intracellular levels of

  15. A novel synthetic Piper amide derivative NED-180 inhibits hyperpigmentation by activating the PI3K and ERK pathways and by regulating Ca2+ influx via TRPM1 channels.

    Science.gov (United States)

    Hwang, Eunson; Lee, Taek Hwan; Lee, Wook-Joo; Shim, Won-Sik; Yeo, Eui-Ju; Kim, Sanghee; Kim, Sun Yeou

    2016-01-01

    Piper amides have a characteristic, unsaturated amide group and exhibit diverse biological activities, including proliferation and differentiation of melanocytes, although the molecular mechanisms underlying its antimelanogenesis effect remain unknown. We screened a selected chemical library of newly synthesized Piper amide derivatives and identified (E)-3-(4-(tert-butyl)phenyl)-N-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)acrylamide (NED-180) as one of the most potent compounds in suppressing melanogenesis. In murine melan-a melanocytes, NED-180 downregulated the expression of melanogenic regulatory proteins including tyrosinase, Tyrp1, Dct, and MITF. PI3K/Akt-dependent phosphorylation of GSK3β by NED-180 decreases MITF phosphorylation and inhibits melanogenesis without any effects on cytotoxicity and proliferation. Furthermore, topical application of NED-180 significantly ameliorated UVB-induced skin hyperpigmentation in guinea pigs. Interestingly, data obtained using calcium imaging techniques suggested that NED-180 reduced the TPA-induced activation of TRPM1 (melastatin), which could explain the NED-180-induced inhibition of melanogenesis. All things taken together, NED-180 triggers activation of multiple pathways, such as PI3K and ERK, and inhibits TRPM1/TRPV1, leading to inhibition of melanogenesis.

  16. Extract from Periostracum cicadae Inhibits Oxidative Stress and Inflammation Induced by Ultraviolet B Irradiation on HaCaT Keratinocytes

    Directory of Open Access Journals (Sweden)

    Tsong-Min Chang

    2017-01-01

    Full Text Available Periostracum cicadae is widely used for the treatment of skin diseases such as eczema, pruritus, and itching. The current study sought to evaluate the effect of P. cicadae extract on ultraviolet B (UVB irradiation and identify the mechanisms involved. Photodamage-protective activity of P. cicadae extracts against oxidative challenge was screened using HaCaT keratinocytes. P. cicadae extracts did not affect cell viability but decreased reactive oxygen species (ROS production. The extract attenuates the expression of interleukin-6 (IL-6, matrix metalloproteinase-2 (MMP-2, and MMP-9 in UVB-treated HaCaT cells. Also, P. cicadae abrogated UVB-induced activation of NF-κB, p53, and activator protein-1 (AP-1. The downmodulation of IL-6 by P. cicadae was inhibited by the p38 inhibitor (SB203580 or JNK inhibitor (SP600125. Moreover, the extract attenuated the expression of NF-κB and induced thrombomodulin in keratinocytes and thereby effectively downregulated inflammatory responses in the skin. The nuclear accumulation and expression of NF-E2-related factor (Nrf2 were increased by P. cicadae treatment. Furthermore, treatment with P. cicadae remarkably ameliorated the skin’s structural damage induced by irradiation. This study demonstrates that P. cicadae may protect skin cells against oxidative insult by modulating ROS concentration, IL-6, MMPs generation, antioxidant enzymes activity, and cell signaling pathways.

  17. Protective effect of Schizandrin B against damage of UVB irradiated skin cells depend on inhibition of inflammatory pathways.

    Science.gov (United States)

    Gao, Chenguang; Chen, Hong; Niu, Cong; Hu, Jie; Cao, Bo

    2017-01-02

    Schizandrin B is extracted from Schisandra chinensis (Turcz.) Baill. This study evaluated the photoprotective effect of Schizandrin B on oxidative stress injury of the skin caused by UVB-irradiation and the molecular mechanism of the photoprotective effect of Schizandrin B, and we firstly found that Schizandrin B could block Cox-2, IL-6 and IL-18 signal pathway to protect damage of skin cells given by UVB-irradiation. In the research, we found that Schizandrin B can attenuate the UVB-induced toxicity on keratinocytes and dermal fibroblasts in human body, and can outstandingly eliminated intracellular ROS produced by UVB-irradiation. These results demonstrate that Schizandrin B can regulate the function of decreasing intracellular SOD's activity and increasing the expression level of MDA in HaCaT cells result from the guidance of UVB, and it markedly reduced the production of inflammatory factors such as Cox-2, IL-6 or IL-18, decreased the expression level of MMP-1, and interdicted degradation process of collagens in UVB-radiated cells. Therefore, skin keratinocytes can be effectively protected from UVB-radiated damage by Schizandrin B, and UVB-irradiation caused inflammatory responses can be inhibited by attenuating process of ROS generating.

  18. Determination of cordycepin content of Cordyceps militaris ...

    African Journals Online (AJOL)

    recombinant rice by high performance liquid chromatography ... caterpillar fungus culture medium powder using twin-screw extrusion technology. ... HPLC analysis was carried out in high ... culture medium: 20 %; total moisture content: 40.

  19. 罗格列酮对 UVB 诱导的小鼠光老化皮肤成纤维细胞MMPs表达和细胞外基质蛋白合成的影响%Effects of rosiglitazone on the MMPs and ECM in UVB induced photo-aging mouse fibroblasts

    Institute of Scientific and Technical Information of China (English)

    陈亮; 杨平; 毕波; 曾继平; 刘天一; 朱宁文; 杨清建; 贾传龙; 卢勇舟; 周轶群

    2015-01-01

    Objective To investigate the influence of Rosiglitazone ( RO ) on the expression of matrix metalloproteinases ( MMPs ) and the synthesis of dermal extracellular matrix ( ECM ) proteins in photo-aging fibroblasts (FBs) induced by UVB. Methods The influence of RO on FBs proliferation was measured by cck 8 as-say. The photo-aging model of FBs was induced by repeated UVB radiation. The influence of RO on the expression of MMPs of photo-aging mice FBs was evaluated by Real-Time PCR at 24 h after the last radiation and the synthesis of collagen I and tropoelastin were detected by western blotting at 48 h after the last radiation. Results No modifica-tion in the proliferative activity of FBs was observed at any dose tested up to 80μM after 48 h. The UVB increased the expressions of MMP-1, 2, 3, 7 and 9 of FBs. But RO pretreatment inhibited the increasing expression of MMPs compared with the UVB group and the synthesis of tropoelastin and collagen I were increased by RO pretreatment in UVB+RO group compared with UVB group. Conclusion RO can maintain the metabolic balance of dermal ECM by decreasing the expression of MMPs and increasing the synthesis of tropoelastin and collagen I in photo-aging FBs. The novel application of RO may lead to innovative and effective anti-photoaging therapies.%目的:探讨罗格列酮( RO)对光老化皮肤成纤维细胞( FBs)基质金属蛋白酶( MMPs)表达和细胞外基质( ECM)蛋白合成的影响。方法采用cck-8法检测RO对FBs活性的影响。 UVB反复照射诱导产生体外细胞光老化模型。造模结束24 h,Real-Time PCR检测MMPs的表达。造模结束48 h, western blotting检测弹性蛋白原和Ⅰ型胶原的表达。结果低剂量RO对FBs的细胞活性无影响。 UVB诱导的光老化FBs中,MMP-1,2,3,7和9的表达均显著升高。40 uM RO能降低UVB引起的MMPs过表达( P <0.05);同时,能在蛋白水平上减缓 UVB 对 FBs 弹性蛋白原和Ⅰ型胶原合成的抑制( P <0.05)。结论 RO可降

  20. Antrodia cinnamomea Inhibits Migration in Human Hepatocellular Carcinoma Cells: The Role of ERp57 and PGK-1.

    Science.gov (United States)

    Chen, Ying-Yi; Liu, Fon-Chang; Wu, Tian-Shung; Sheu, Ming-Jyh

    2015-01-01

    Evidences suggest that ERp57 and PGK-1 signaling lead to cancer cell proliferation and migration. We hypothesized that ERp57 and PGK-1 down-regulation may inactivate matrix metalloproteinase (MMP)-2, -9 expressions and inhibit hepatocellular carcinoma (HCC) migration. Antrodia cinnamomea is widely prescribed as an adjuvant to treat HCC in Taiwan. We aimed to investigate if ethanol extract of fruiting bodies of Antrodia cinnamomea (EEAC) and its active ingredients (i.e., zhankuic acid A, cordycepin, and adenosine) can modulate HCC cancer cells migration through ERp57 and PGK-1 and other molecular pathways such as PI3K/Akt and MAPK. ERp57 and PGK-1 siRNA were transfected into HCC to determine effects on MMP-2/-9 expressions and cell migration. We then examined the inhibitory effects of EEAC and its active ingredients on HCC migration and its related mechanisms including ERp57, PGK-1, PI3K/Akt, and MAPK signaling pathways. Down-regulation of ERp57 and PGK-1 by siRNA decreased MMP-2, -9 expressions and Transwell cell migration in HCC. Nontoxic EEAC markedly inhibited migration of HCC, and significantly inhibited activities and protein expressions of MMP-2 and -9, while the expression of the endogenous inhibitors (TIMP-1 and TIMP-2) of these proteins increased. Nontoxic EEAC and its active ingredients decreased ERp57, GLUD-1, GST-pi, and PGK-1 protein expressions. Finally, nontoxic EEAC inhibited the phosphorylated FAK, PI3K/Akt, and MAPK signaling. Our findings first indicate that EEAC and its ingredients effectively suppress HCC migration. Additionally, the molecular mechanisms appear to be mediated, in part, through the down-regulation of ERp57, PGK-1, MAPK, and PI3K/Akt.

  1. The effect of topically extravirgin olive oil on the UVB-induced immunosuppression

    OpenAIRE

    AriefBudiyanto, Irianiwati, Vohanes Widodo Wirohadidjojo

    2015-01-01

    Background: UVBradiation may act as an immunosuppressive agent through Langernans cells (LCs)depletion correlated with cyclobuthane pyrimidine dimer (CPD), as the most mutagenic photoproducts. Other studies showed that olive oil can prevent various human cancers, which are defect of immune-surveillance. The effect of olive oil in the UVBinduced LCs depletion is still unclear. Objective: To discover the topical effect of extravirgin-olive-oil in the LCs depletion. Methods: A simple experimenta...

  2. Grape seed extract as photochemopreventive agent against UVB-induced skin cancer.

    Science.gov (United States)

    Perde-Schrepler, Maria; Chereches, Gabriela; Brie, Ioana; Tatomir, Corina; Postescu, Ion Dan; Soran, Loredana; Filip, Adriana

    2013-01-05

    In the recent years, the use of natural antioxidants as photochemoprotective agents against skin damages produced by ultraviolet radiation gained considerable attention. Our goal was to show that the hydroethanolic extract obtained from red grape seeds, Burgund Mare (BM) variety could have a protective effect on keratinocytes exposed to UVB radiation. HaCaT keratinocytes were treated with BM extract 30 min. before UVB exposure. The effect was evaluated by assessing cell viability with MTT; the generation of lipid peroxides with malondialdehide (MDA) assay; DNA damage using comet assay; the quantification of DNA photolesions by ELISA and apoptosis by immunocytochemistry with AnnexinV. After irradiation with UVB, HaCaT cells pretreated with BM showed: increased cell viability compared to those exposed to UVB only; significantly lower lipid peroxides level; the lesion scores and DNA photolesions were significantly lower and a significant reduction of the cells undergoing apoptosis. These results recommend the use of the BM extract as photochemoprotective agent as such or in combination with sunscreens and/or other natural products with similar or complementary properties. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Cellular target of UVB-induced DNA damage resulting in local suppression of contact hypersensitivity

    NARCIS (Netherlands)

    Vink, A.A.; Shreedhar, V.; Roza, L.; Krutmann, J.; Kripke, M.L.

    1998-01-01

    Experimental data are reviewed that lend support to the hypothesis that formation of DNA damage is the initiation event of local suppression of contact hypersensitivity (CHS) after exposure to ultraviolet (UV) radiaton and that the antigen-presenting cell (APC) is an important traget for this DNA da

  4. Effect of biflavones of Ginkgo biloba against UVB-induced cytotoxicity in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seong-Jin [Chonnam National Univ., Kwangju (Korea, Republic of). Medical School

    2001-04-01

    The effect of Ginkgo biloba extract on Ultraviolet B (UVB) irradiated fibroblasts was examined by using a neutral red dye uptake assay and a lactic dehydrogenase (LDH) release assay. Crude extract along with individual components, including flavone-glycosides and biflavones, were applied to cultured normal human skin fibroblasts for 12 hours, and 0, 20, 40 and 80 mJ/cm{sup 2} of UVB were irradiated. Two synthetic flavonoids, quercetin and rutin, which have polyphenol structures close to the flavonoids in Ginkgo biloba extract, were used to compare any structure-related activity under the same conditions. At the concentrations (from 0.25 to 2 mg/ml) treated with biflavone components (isoginkgetin/ginkgetin, sciadopitysin) and quercetin, high neutral red dye uptake was detected with gradual increases in UVB irradiation. The time-course release of LDH was determined as the cytotoxicity index (%) during 24 hours following a high dose UVB irradiation (200 mJ/cm{sup 2}), and the pattern of this cytotoxicity index was similar to that of the neutral red dye uptake results. Sciadopitysin, isoginkgetin/ginkgetin and quercetin treatments lowered cytotoxicity indices to 50.81, 67.81 and 62.19%, respectively, compared to 95.38% for the untreated control. The antioxidant potential of biflavones of Ginkgo biloba could be explained on the basis of structure-related activity; hydroxy- and methyl-substitutions on the basic structure of these flavonoids played a role, as other reports have suggested. (author)

  5. UV-B induced changes in the secondary metabolites of Morus alba L. leaves.

    Science.gov (United States)

    Gu, Xi-Da; Sun, Ming-Yao; Zhang, Lin; Fu, Hong-Wei; Cui, Lei; Chen, Run-Ze; Zhang, Da-Wei; Tian, Jing-Kui

    2010-04-27

    Ultraviolet-B (UV-B) radiation is harmful to plants and human beings. Many secondary metabolites, like flavonoids, alkaloids, and lignin, are UV-B absorbing compounds, which can protect the genetic material of plants. Furthermore, they are active components of herbal drugs. UV-B radiation can activate the self-protective secondary metabolism system. The results of this paper provide a method to induce bioactive secondary metabolites from mulberry leaves (Morus alba L.) by UV-B irradiation in vitro. Five significantly different chromatographic peaks were found by HPLC fingerprint after induction, from which two active compounds were identified: One was chalcomoracin, a natural Diels-Alder type adduct with antibacterial activity; the other one was moracin N, which is a precursor of chalcomoracin. Their contents were 0.818 mg/g and 0.352 mg/g by dry weight, respectively.

  6. UV-B Induced Changes in the Secondary Metabolites of Morus alba L. Leaves

    OpenAIRE

    Da-Wei Zhang; Jing-Kui Tian; Run-Ze Chen; Lei Cui; Hong-Wei Fu; Lin Zhang; Ming-Yao Sun; Xi-Da Gu

    2010-01-01

    Ultraviolet-B (UV-B) radiation is harmful to plants and human beings. Many secondary metabolites, like flavonoids, alkaloids, and lignin, are UV-B absorbing compounds, which can protect the genetic material of plants. Furthermore, they are active components of herbal drugs. UV-B radiation can activate the self-protective secondary metabolism system. The results of this paper provide a method to induce bioactive secondary metabolites from mulberry leaves (Morus alba L.) by UV-B irradiation in ...

  7. UV-B Induced Changes in the Secondary Metabolites of Morus alba L. Leaves

    Directory of Open Access Journals (Sweden)

    Da-Wei Zhang

    2010-04-01

    Full Text Available Ultraviolet-B (UV-B radiation is harmful to plants and human beings. Many secondary metabolites, like flavonoids, alkaloids, and lignin, are UV-B absorbing compounds, which can protect the genetic material of plants. Furthermore, they are active components of herbal drugs. UV-B radiation can activate the self-protective secondary metabolism system. The results of this paper provide a method to induce bioactive secondary metabolites from mulberry leaves (Morus alba L. by UV-B irradiation in vitro. Five significantly different chromatographic peaks were found by HPLC fingerprint after induction, from which two active compounds were identified: One was chalcomoracin, a natural Diels-Alder type adduct with antibacterial activity; the other one was moracin N, which is a precursor of chalcomoracin. Their contents were 0.818 mg/g and 0.352 mg/g by dry weight, respectively.

  8. COP1 contributes to UVB-induced signaling in human keratinocytes.

    Science.gov (United States)

    Kinyó, Agnes; Kiss-László, Zsuzsanna; Hambalkó, Szabolcs; Bebes, Attila; Kiss, Mária; Széll, Márta; Bata-Csörgo, Zsuzsanna; Nagy, Ferenc; Kemény, Lajos

    2010-02-01

    UVB irradiation has been shown to trigger a broad range of changes in gene expression in human skin; however, factors governing these events are still not well understood. In this study, we show that human constitutive photomorphogenic protein-1 (huCOP1), an E3 ligase, contributes to the orchestration of UVB response of keratinocytes. Accordingly, our data show that (i) huCOP1 protein is expressed both in the nucleus and in the cytoplasm of cultured keratinocytes, (ii) UVB reduces the levels of the huCOP1 mRNA and protein, and (iii) induces changes in the subcellular localization of huCOP1. Finally, we show that gene-specific silencing of huCOP1 induces the accumulation of the tumor suppressor p53 protein, which is further increased after UVB irradiation.

  9. The Role of Altered Nucleotide Excision Repair and UVB-Induced DNA Damage in Melanomagenesis

    Directory of Open Access Journals (Sweden)

    Timothy Budden

    2013-01-01

    Full Text Available UVB radiation is the most mutagenic component of the UV spectrum that reaches the earth’s surface and causes the development of DNA damage in the form of cyclobutane pyrimidine dimers and 6-4 photoproducts. UV radiation usually results in cellular death, but if left unchecked, it can affect DNA integrity, cell and tissue homeostasis and cause mutations in oncogenes and tumour-suppressor genes. These mutations, if unrepaired, can lead to abnormal cell growth, increasing the risk of cancer development. Epidemiological data strongly associates UV exposure as a major factor in melanoma development, but the exact biological mechanisms involved in this process are yet to be fully elucidated. The nucleotide excision repair (NER pathway is responsible for the repair of UV-induced lesions. Patients with the genetic disorder Xeroderma Pigmentosum have a mutation in one of eight NER genes associated with the XP complementation groups XP-A to XP-G and XP variant (XP-V. XP is characterized by diminished repair capacity, as well as a 1000-fold increase in the incidence of skin cancers, including melanoma. This has suggested a significant role for NER in melanoma development as a result of UVB exposure. This review discusses the current research surrounding UVB radiation and NER capacity and how further investigation of NER could elucidate the role of NER in avoiding UV-induced cellular death resulting in melanomagenesis.

  10. Differential UVB-induced modulation of cytokine production in XPA, XPC, and CSB repair-deficient mice

    NARCIS (Netherlands)

    Boonstra, A.P.; Oudenaren, van A.; Baert, M.R.M.; Steeg, van H.; Leenen, P.J.; Horst, van der G.T.J.; Hoeijmakers, J.H.J.; Savelkoul, H.F.J.; Garssen, J.

    2001-01-01

    Ultraviolet B irradiation has serious consequences for cellular immunity and can suppress the rejection of skin tumors and the resistance to infectious diseases. DNA damage plays a crucial role in these immunomodulatory effects of ultraviolet B, as impaired repair of ultraviolet-B-induced DNA damage

  11. Z-ligustilide ameliorated ultraviolet B-induced oxidative stress and inflammatory cytokine production in human keratinocytes through upregulation of Nrf2/HO-1 and suppression of NF-κB pathway.

    Science.gov (United States)

    Wu, Zhouwei; Uchi, Hiroshi; Morino-Koga, Saori; Shi, Weimin; Furue, Masutaka

    2015-09-01

    Ultraviolet B (UVB), a harmful environmental factor, is responsible for a variety of skin disorders including skin inflammation through reactive oxygen species (ROS) and inflammatory mediator production. Here, we investigated the effect of Z-ligustilide (Z-lig), an active ingredient isolated from the medicinal plants Cnidium officinale and Angelica acutiloba, on UVB-induced ROS generation and inflammatory mediator production in normal human epidermal keratinocytes (NHEKs) as well as its underlying mechanisms. Z-lig significantly rescued UVB-induced NHEKs damage in a dosage-dependent manner. Pretreatment of NHEKs with Z-lig inhibited UVB-induced ROS production in NHEKs. Both silencing the nuclear factor E2-related factor 2 (Nrf2) and the supplement of tin protoporphyrin IX (SnPP), a haeme oxygenase-1 (HO-1) inhibitor, cancelled the inhibitory effect of Z-lig on UVB-induced ROS upregulation in NHEKs. Moreover, pretreatment of NHEKs with Z-lig reduced UVB-induced nuclear factor kappa B (NF-κB)-dependent inflammatory mediators (IL-6, IL-8 and MCP-1) production at both mRNA and protein level. In the presence of Z-lig, UVB-induced NF-κB subunit p65 nuclear translocation was abolished, and the IκBα degradation was suppressed. Taken together, these findings suggest that Z-lig can suppress UVB-induced ROS generation through Nrf2/HO-1 upregulation and inflammation by suppressing the NF-κB pathway, suggesting that Z-lig may be beneficial in protecting skin from UVB exposure.

  12. Salicylic acid protects the skin from UV damage.

    Science.gov (United States)

    Mammone, Thomas; Gan, David; Goyarts, Earl; Maes, Daniel

    2006-01-01

    Aspirin(acetyl salicylate) has long been used as an analgesic. Salicylic acid has been reported to have anti-inflammatory properties. These activities include inhibiting activity of cox-1, cox-2, and NF-kb. In addition, salicylic acid has also been shown in some systems to induce Hsp70. We have demonstrated that salicylic acid inhibits UVB-induced sunburn cell formation, as well as increase the removal of UVB induced TT dimer formation in living skin equivalents. Given these protective properties of salicylic acid, we propose the use of salicylic acid as a topical therapeutic to protect the skin from sun damage.

  13. Reciprocal inhibition in man.

    Science.gov (United States)

    Crone, C

    1993-11-01

    Reciprocal inhibition is the automatic antagonist alpha motor neurone inhibition which is evoked by contraction of the agonist muscle. This so-called natural reciprocal inhibition is a ubiquitous and pronounced phenomenon in man and must be suspected of playing a major role in the control of voluntary movements. The spinal pathways underlying this inhibitory phenomenon were studied. The disynaptic reciprocal Ia inhibitory pathway between the tibial anterior muscle and the soleus alpha motor neurones was identified and described in man. It was shown that the inhibition can be evoked in most healthy subjects at rest, but the degree of inhibition varies considerably from one subject to another. It was concluded that it corresponds to the disynaptic reciprocal Ia inhibitory pathway which has been extensively described in animal experiments. The disynaptic reciprocal inhibition was shown to increase during the dynamic phase of a dorsiflexion movement of the foot, but not during the tonic phase. However, when the peripheral afferent feedback from the contracting muscle was blocked by ischaemia, an increase of the inhibition was revealed also during the tonic phase of the dorsiflexion. The concealment of this increase during unrestrained peripheral feedback from the muscle was thought to be due to the post-activation depression mechanism; a mechanism which was described further and which probably involves reduced transmitter release at Ia afferent terminals as a result of previous activation of these afferent fibers. Hence the hypothesis was supported that alpha motor neurones and the corresponding inhibitory interneurones, which project reciprocal inhibition to the antagonist motor neurones, are activated in parallel during voluntary contraction of agonist muscles. An additional reciprocal inhibitory mechanism, the long latency reciprocal inhibition, was described between the tibial anterior muscle and the soleus alpha motor neurones. It was shown to be evoked by group I

  14. Potentiation of latent inhibition.

    Science.gov (United States)

    Rodriguez, Gabriel; Hall, Geoffrey

    2008-07-01

    Rats were given exposure either to an odor (almond) or a compound of odor plus taste (almond plus saline), prior to training in which the odor served as the conditioned stimulus. It was found, for both appetitive and aversive procedures, that conditioning was retarded by preexposure (a latent inhibition effect), and the extent of the retardation was greater in rats preexposed to the compound (i.e., latent inhibition to the odor was potentiated by the presence of the taste). In contrast, the presence of the taste during conditioning itself overshadowed learning about the odor. We argue that the presence of the salient taste in compound with the odor enhances the rate of associative learning, producing a rapid loss in the associability of the odor. This loss of associability will generate both overshadowing and the potentiation of latent inhibition that is observed after preexposure to the compound.

  15. Inhibitors of cysteine cathepsin and calpain do not prevent ultraviolet-B-induced apoptosis in human keratinocytes and HeLa cells

    DEFF Research Database (Denmark)

    Bang, Bo; Baadsgaard, Ole; Skov, Lone

    2004-01-01

    Caspases, members of the cysteine protease family, execute UVB-induced apoptosis in several cell lines and keratinocytes. Several researchers investigating UVB-induced apoptosis have demonstrated a dose-dependent protective effect of the synthetic peptide caspase inhibitor zVAD-fmk. However, z......VAD-fmk displays a dose-dependent protective effect against UVB-induced apoptosis, even at doses higher than those required to block all known proapoptotic caspases. In addition, it is known that zVAD-fmk also inhibits other cysteine proteases including cathepsins and calpains, and these proteases have recently....... This was done by investigating the effect of the irreversible cysteine protease inhibitor zFA-fmk, the cathepsin B inhibitor CA-074-Me and the calpain inhibitor ALLN on the viability of UVB-irradiated human keratinocytes and HeLa cells. At concentrations of 10 microM and above zVAD-fmk conferred partial dose...

  16. Quorum sensing inhibition

    DEFF Research Database (Denmark)

    Persson, T.; Givskov, Michael Christian; Nielsen, J.

    2005-01-01

    /receptor transcriptional regulator in some clinically relevant Gram-negative bacteria. The present review contains all reported compound types that are currently known to inhibit the QS transcriptional regulator in Gram-negative bacteria. These compounds are sub-divided into two main groups, one comprising structural...

  17. Enzyme inhibition by iminosugars

    DEFF Research Database (Denmark)

    López, Óscar; Qing, Feng-Ling; Pedersen, Christian Marcus

    2013-01-01

    Imino- and azasugar glycosidase inhibitors display pH dependant inhibition reflecting that both the inhibitor and the enzyme active site have groups that change protonation state with pH. With the enzyme having two acidic groups and the inhibitor one basic group, enzyme-inhibitor complexes...

  18. Post-ischemic treatment of WIB801C, standardized Cordyceps extract, reduces cerebral ischemic injury via inhibition of inflammatory cell migration.

    Science.gov (United States)

    Hwang, Sunyoung; Cho, Geum-Sil; Ryu, Sangwoo; Kim, Hoon J; Song, Hwa Young; Yune, Tae Y; Ju, Chung; Kim, Won-Ki

    2016-06-20

    Anti-inflammatory therapy has been intensively investigated as a potential strategy for treatment of cerebral stroke. However, despite many positive outcomes reported in animal studies, anti-inflammatory treatments have not proven successful in humans as yet. Although immunomodulatory activity and safety of Cordyceps species (Chinese caterpillar fungi) have been proven in clinical trials and traditional Asian prescriptions for inflammatory diseases, its anti-ischemic effect remains elusive. In the present study, therefore, we investigated the potential therapeutic efficacy of WIB801C, the standardized extract of Cordyceps militaris, for treatment of cerebral ischemic stroke. The anti-chemotactic activity of WIB801C was assayed in cultured rat microglia/macrophages. Sprague-Dawley rats were subjected to ischemic stroke via either transient (1.5-h tMCAO and subsequent 24-h reperfusion) or permanent middle cerebral artery occlusion (pMCAO for 24-h without reperfusion). WIB801C was orally administered twice at 3- and 8-h (50mg/kg each) after the onset of MCAO. Infarct volume, edema, blood brain barrier and white matter damages, neurological deficits, and long-term survival rates were investigated. The infiltration of inflammatory cells into ischemic lesions was assayed by immunostaining. WIB801C significantly decreased migration of cultured microglia/macrophages. This anti-chemotactic activity of WIB-801C was not mediated via adenosine A3 receptors, although cordycepin, the major ingredient of WIB801C, is known as an adenosine receptor agonist. Post-ischemic treatment with WIB801C significantly reduced the infiltration of ED-1-and MPO-positive inflammatory cells into ischemic lesions in tMCAO rats. WIB801C-treated rats exhibited significantly decreased infarct volume and cerebral edema, less white matter and blood-brain barrier damages, and improved neurological deficits. WIB801C also improved survival rates over 34 days after ischemia onset. A significant reduction in

  19. Plastics for corrosion inhibition

    CERN Document Server

    Goldade, Victor A; Makarevich, Anna V; Kestelman, Vladimir N

    2005-01-01

    The development of polymer composites containing inhibitors of metal corrosion is an important endeavour in modern materials science and technology. Corrosion inhibitors can be located in a polymer matrix in the solid, liquid or gaseous phase. This book details the thermodynamic principles for selecting these components, their compatibility and their effectiveness. The various mechanisms of metal protection – barrier, inhibiting and electromechanical – are considered, as are the conflicting requirements placed on the structure of the combined material. Two main classes of inhibited materials (structural and films/coatings) are described in detail. Examples are given of structural plastics used in friction units subjected to mechano-chemical wear and of polymer films/coatings for protecting metal objects against corrosion.

  20. Inhibition and Brain Work

    OpenAIRE

    Buzsáki, György; Kaila, Kai; Raichle, Marcus

    2007-01-01

    The major part of the brain’s energy budget (~60%–80%) is devoted to its communication activities. While inhibition is critical to brain function, relatively little attention has been paid to its metabolic costs. Understanding how inhibitory interneurons contribute to brain energy consumption (brain work) is not only of interest in understanding a fundamental aspect of brain function but also in understanding functional brain imaging techniques which rely on measurements related to blood flow...

  1. Thymus vulgaris alleviates UVB irradiation induced skin damage via inhibition of MAPK/AP-1 and activation of Nrf2-ARE antioxidant system.

    Science.gov (United States)

    Sun, Zhengwang; Park, Sang Yong; Hwang, Eunson; Zhang, Mengyang; Seo, Seul A; Lin, Pei; Yi, Tae-Hoo

    2017-02-01

    Solar ultraviolet (UV) radiation-induced reactive oxidative species is mainly responsible for the development of photoageing. Rosmarinic acid was one of the main bioactive components detected in Thymus vulgaris (TV) we extracted. In this study, UVB-induced skin damages have been shown to be ameliorated by treatment with TV in hairless mice (HR-1) skin, demonstrated by decreased matrix metalloproteinases (MMPs) and increased collagen production. However, the underlying molecular mechanism on which TV acted was unclear. We examined the photoprotective effects of TV against UVB and elucidated the molecular mechanism in normal human dermal fibroblasts. Thymus vulgaris remarkably prevented the UVB-induced reactive oxygen species and lactate dehydrogenase. Dose-dependent increase in glutathione, NAD(P)H: quinone oxidoreductase1 and heme oxygenase-1, by TV was confirmed by increased nuclear accumulation of Nrf2. Furthermore, 5-Methoxyindole-2-carboxylic acid was introduced as a specific inhibitor of dihydrolipoyl dehydrogenase (DLD). We demonstrated that Nrf2 expression was regulated by DLD, which was a tricarboxylic acid cycle-associated protein that decreased after UVB exposure. Besides, TV significantly diminished UVB induced phosphorylation of mitogen activated protein kinases pathway, containing extracellular signal-regulated kinase, Jun N-terminal kinase and p38, which consequently reduced phosphorylated c-fos and c-jun. Our results suggest that TV is a potential botanical agent for use against UV radiation-induced oxidative stress mediated skin damages. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  2. Antiinflammatory and Antiphotodamaging Effects of Ergostatrien-3β-ol, Isolated from Antrodia camphorata, on Hairless Mouse Skin

    Directory of Open Access Journals (Sweden)

    Yueh-Hsiung Kuo

    2016-09-01

    Full Text Available Ergostatrien-3β-ol (EK100, isolated from the submerged whole broth of Antrodia camphorata, has antidiabetic, hyperlipidemic, and hepatoprotective activities. However, the antiphotodamage activity of EK100 has still not been revealed. Inflammation and collagen degradation contribute to skin photodamage and premature aging. In the present study, in vivo experiments were designed to investigate the antiinflammatory and antiphotodamaging activities of EK100 in hairless mice by physiological and histological analysis of the skin. Results indicated that topical application of EK100 (25 and 100 μM for 10 weeks efficiently inhibited ultraviolet B (UVB-induced wrinkle formation, erythema, and epidermal thickness in the mice skin. EK100 also restored UVB-induced collagen content reduction in hairless mice skin. In addition, the immunohistochemistry results indicated that EK100 significantly inhibited the UVB-induced expression of matrix metalloproteinase-1 (MMP-1, interleukin-6 (IL-6, inducible nitric oxide synthase (iNOS, and nuclear factor kappaB (NF-κB in the mouse skin. The expression of these proteins was similar to the Normal group after 100 μM EK100 treatment. EK100 inhibited collagen degradation in the skin through MMP-1 inhibition and antiinflammation. EK100 significantly reduced the transepidermal water loss (TEWL, indicating that EK100 protected skin from UVB-induced damage. Our findings strongly suggest that EK100 has significant beneficial antiinflammatory and antiphotoaging activities and that EK100 can be developed as an antiphotodamaging agent.

  3. Latent inhibition in schizophrenia.

    Science.gov (United States)

    Swerdlow, N R; Braff, D L; Hartston, H; Perry, W; Geyer, M A

    1996-05-01

    Latent inhibition (LI) refers to the retarded acquisition of a conditioned response that occurs if the subject being tested is first preexposed to the to-be-conditioned stimulus (CS) without the paired unconditioned stimulus (UCS). Because the 'irrelevance' of the to-be-conditioned stimulus is established during non-contingent preexposure, the slowed acquisition of the CS-UCS association is thought to reflect the process of overcoming this learned irrelevance. Latent inhibition has been reported to be diminished in acutely hospitalized schizophrenia patients. If acutely hospitalized schizophrenia patients are preexposed to the CS, they learn the association as fast as, and perhaps faster than, patients who are not preexposed to the CS. This finding has been interpreted as reflecting the inability of acute schizophrenia patients to ignore irrelevant stimuli. In this study, the LI paradigm was identical to the one used in previous reports of LI deficits in schizophrenia patients (Baruch et al., 1988). Latent inhibition was observed in normal control subjects (n = 73), including individuals identified as 'psychosis-prone' based on established screening criteria, and in anxiety (n = 19) and mood disorder (n = 13) patients. Learning scores (trials to criterion) in "acutely' hospitalized as well as "chronic' hospitalized schizophrenia patients (n = 45) were significantly elevated in both preexposed and non-preexposed subjects, compared to controls. Acute schizophrenia patients exhibited intact LI. Separate cohorts of acute and chronic schizophrenia patients (n = 23) and normal controls (n = 34) exhibited intact LI when tested in a new, easier-to-acquire computerized LI paradigm. These results fail to identify specific LI deficits in schizophrenia patients, and raise the possibility that previously observed LI deficits in schizophrenia patients may reflect, at least in part, performance deficits related to learning acquisition.

  4. Beneficial bacteria inhibit cachexia.

    Science.gov (United States)

    Varian, Bernard J; Goureshetti, Sravya; Poutahidis, Theofilos; Lakritz, Jessica R; Levkovich, Tatiana; Kwok, Caitlin; Teliousis, Konstantinos; Ibrahim, Yassin M; Mirabal, Sheyla; Erdman, Susan E

    2016-03-15

    Muscle wasting, known as cachexia, is a debilitating condition associated with chronic inflammation such as during cancer. Beneficial microbes have been shown to optimize systemic inflammatory tone during good health; however, interactions between microbes and host immunity in the context of cachexia are incompletely understood. Here we use mouse models to test roles for bacteria in muscle wasting syndromes. We find that feeding of a human commensal microbe, Lactobacillus reuteri, to mice is sufficient to lower systemic indices of inflammation and inhibit cachexia. Further, the microbial muscle-building phenomenon extends to normal aging as wild type animals exhibited increased growth hormone levels and up-regulation of transcription factor Forkhead Box N1 [FoxN1] associated with thymus gland retention and longevity. Interestingly, mice with a defective FoxN1 gene (athymic nude) fail to inhibit sarcopenia after L. reuteri therapy, indicating a FoxN1-mediated mechanism. In conclusion, symbiotic bacteria may serve to stimulate FoxN1 and thymic functions that regulate inflammation, offering possible alternatives for cachexia prevention and novel insights into roles for microbiota in mammalian ontogeny and phylogeny.

  5. Salvianolic Acid B Protects Normal Human Dermal Fibroblasts Against Ultraviolet B Irradiation-Induced Photoaging Through Mitogen-Activated Protein Kinase and Activator Protein-1 Pathways.

    Science.gov (United States)

    Sun, Zhengwang; Park, Sang-Yong; Hwang, Eunson; Zhang, Mengyang; Jin, Fengxie; Zhang, Baochun; Yi, Tae Hoo

    2015-01-01

    Exposure to ultraviolet (UV) light causes increased matrix metalloproteinase (MMP) activity and decreased collagen synthesis, leading to skin photoaging. Salvianolic acid B (SAB), a polyphenol, was extracted and purified from salvia miltiorrhiza. We assessed effects of SAB on UVB-induced photoaging and investigated its molecular mechanism of action in UVB-irradiated normal human dermal fibroblasts. Our results show that SAB significantly inhibited the UVB-induced expression of metalloproteinases-1 (MMP-1) and interleukin-6 (IL-6) while promoting the production of type I procollagen and transforming growth factor β1 (TGF-β1). Moreover, treatment with SAB in the range of 1-100 μg/mL significantly inhibited UVB-induced extracellular signal-regulated kinase (ERK), Jun N-terminal kinase (JNK) and p38 phosphorylation, which resulted in decreasing UVB-induced phosphorylation of c-Fos and c-Jun. These results indicate that SAB downregulates UV-induced MMP-1 expression by inhibiting Mitogen-activated protein kinase (MAPK) signaling pathways and activator protein-1 (AP-1) activation. Our results suggest a potential use for SAB in skin photoprotection.

  6. Can Arousal Modulate Response Inhibition?

    Science.gov (United States)

    Weinbach, Noam; Kalanthroff, Eyal; Avnit, Amir; Henik, Avishai

    2015-01-01

    The goal of the present study was to examine if and how arousal can modulate response inhibition. Two competing hypotheses can be drawn from previous literature. One holds that alerting cues that elevate arousal should result in an impulsive response and therefore impair response inhibition. The other suggests that alerting enhances processing of…

  7. Lateral inhibition during nociceptive processing

    DEFF Research Database (Denmark)

    Quevedo, Alexandre S.; Mørch, Carsten Dahl; Andersen, Ole Kæseler

    2017-01-01

    of skin. Thus, the stimulation of the skin region between the endpoints of the lines appears to produce inhibition. These findings indicate that lateral inhibition limits spatial summation of pain and is an intrinsic component of nociceptive information processing. Disruption of such lateral inhibition......Spatial summation of pain is the increase of perceived intensity that occurs as the stimulated area increases. Spatial summation of pain is sub-additive in that increasing the stimulus area produces a disproportionately small increase in the perceived intensity of pain. A possible explanation...... for sub-additive summation may be that convergent excitatory information is modulated by lateral inhibition. To test the hypothesis that lateral inhibition may limit spatial summation of pain, we delivered different patterns of noxious thermal stimuli to the abdomens of 15 subjects using a computer...

  8. Skin photoprotection by green tea: antioxidant and immunomodulatory effects.

    Science.gov (United States)

    Katiyar, Santosh K

    2003-09-01

    Because of a characteristic aroma and health benefits, green tea is consumed worldwide as a popular beverage. The epicatechin derivatives, commonly called polyphenols, present in green tea possess antioxidant, anti-inflammatory and anti-carcinogenic properties. The major and most highly chemopreventive constituent in green tea responsible for the biochemical or pharmacological effects is (-)-epigallocatechin-3-gallate (EGCG). Epidemiological, clinical and biological studies have implicated that solar ultraviolet (UV) light is a complete carcinogen and repeated exposure can lead to the development of various skin disorders including melanoma and nonmelanoma skin cancers. We and others have shown that topical treatment or oral consumption of green tea polyphenols (GTP) inhibit chemical carcinogen- or UV radiation-induced skin carcinogenesis in different laboratory animal models. Topical treatment of GTP and EGCG or oral consumption of GTP resulted in prevention of UVB-induced inflammatory responses, immunosuppression and oxidative stress, which are the biomarkers of several skin disease states. Topical application of GTP and EGCG prior to exposure of UVB protects against UVB-induced local as well as systemic immune suppression in laboratory animals, which was associated with the inhibition of UVB-induced infiltration of inflammatory leukocytes. Prevention of UVB-induced suppression of immune responses by EGCG was also associated with the reduction in immunosuppressive cytokine interleukin (IL)-10 production at UV irradiated skin and draining lymph nodes, whereas IL-12 production was significantly enhanced in draining lymph nodes. Antioxidant and anti-inflammatory effects of green tea were also observed in human skin. Treatment of EGCG to human skin resulted in the inhibition of UVB-induced erythema, oxidative stress and infiltration of inflammatory leukocytes. We also showed that treatment of GTP to human skin prevents UVB-induced cyclobutane pyrimidine dimers

  9. Taurine inhibits interleukin-6 expression and release induced by ultraviolet B exposure to human retinal pigment epithelium cells.

    Science.gov (United States)

    Dayang, Wu; Jinsong, Zhang

    2015-01-01

    The massive uptake of compatible osmolytes is a self-protective response shared by retina exposed to hypertonic stress and ultraviolet stress. This study aimed to investigate the protective effects of taurine against ultraviolet damage in human retinal pigment epithelium cells. Real-time PCR, radioimmunoassay, ELISA and immunoassay were used to measure osmolyte uptake and IL-6 expression. Compared with normotonic stress, hypertonic stress led to an induction of osmolyte uptake including betaine, myoinositol and taurine. UVB exposure upregulated osmolyte transporter mRNA expression and increased osmolyte uptake respectively. Especially, taurine suppressed UVB-induced IL-6 mRNA expression significantly. The accumulation of IL-6 in UVB-exposed human retinal pigment epithelial cells supernatant was much slower when the cells were preincubated with taurine. Moreover, taurine suppressed IL-6 concentration in aqueous humour. The effect of compatible osmolyte taurine on IL-6 expression and release may play an important role in cell resistance and adaption to UVB exposure.

  10. Flavonoids Derived from Abelmoschus esculentus Attenuates UV-B Induced Cell Damage in Human Dermal Fibroblasts Through Nrf2-ARE Pathway

    OpenAIRE

    Juilee Patwardhan; Purvi Bhatt

    2016-01-01

    Background: Ultraviolet-B (UV-B) radiation is a smaller fraction of the total radiation reaching the Earth but leads to extensive damage to the deoxyribonucleic acid (DNA) and other biomolecules through formation of free radicals altering redox homeostasis of the cell. Abelmoschus esculentus (okra) has been known in Ayurveda as antidiabetic, hypolipidemic, demulscent, antispasmodic, diuretic, purgative, etc. Objective: The aim of this study is to evaluate the protective effect of flavonoids f...

  11. Characterisation of Human Keratinocytes by Measuring Cellular Repair Capacity of UVB-Induced DNA Damage and Monitoring of Cytogenetic Changes in Melanoma Cell Lines

    Energy Technology Data Exchange (ETDEWEB)

    Greinert, R.; Breibart, E.W.; Mitchell, D.; Smida, J.; Volkmer, B

    2000-07-01

    The molecular mechanisms for UV-induced photocarcinogenesis are far from being understood in detail, especially in the case of malignant melanoma of the skin. Nevertheless, it is known that deficiencies in cellular repair processes of UV-induced DNA damage (e.g. in the case of Xeroderma pigmentosum) represent important aetiological factors in the multistep development of skin cancer. The repair kinetics have therefore been studied of an established skin cell line (HaCaT), primary human keratinocytes, melanocytes and melanoma cell lines, using fluorescence microscopy and flow cytometry. Our data show a high degree of interindividual variability in cellular repair capacity for UV-induced DNA lesions, which might be due to individual differences in the degree of tolerable damage and/or the onsets of saturation of the enzymatic repair system. The cytogenetic analysis of melanoma cell lines, using spectral karyotyping (SKY) furthermore proves that malignant melanoma of the skin are characterised by high numbers of chromosomal aberrations. (author)

  12. Novel pathway for N1-acetyl-5-methoxykynuramine: UVB-induced liberation of carbon monoxide from precursor N1-acetyl-N2-formyl-5-methoxykynuramine.

    Science.gov (United States)

    Seever, Katinka; Hardeland, Rüdiger

    2008-05-01

    Irradiation of the melatonin metabolite N(1)-acetyl-N(2)-formyl-5-methoxykynuramine (AFMK) with UV light of 254 nm causes the release of carbon monoxide (CO) and, thus, deformylation to N(1)-acetyl-5-methoxykynuramine (AMK). Liberation of CO was demonstrated by reduction of PdCl(2) to metallic palladium, under avoidance of actions by other reductants. Photochemical AMK formation was not due to UV-induced hydroxyl radicals, because the reaction also took place with high efficiency in ethanol and 2-propanol. Moreover, AMK was generated from AFMK by UVB on a dry thin layer chromatographic plate. Although AMK seems to be the major primary product generated by UVB radiation, prolonged exposure of AFMK led to various other products, especially formed by destruction of AMK, as shown by irradiation of this latter compound. With regard to the demonstration of melatonin in skin and substantial amounts of AFMK in keratinocytes, these findings may be of dermatologic relevance.

  13. Effects of UVB-induced oxidative stress on protein expression and specific protein oxidation in normal human epithelial keratinocytes: a proteomic approach

    Directory of Open Access Journals (Sweden)

    De Marco Federico

    2010-03-01

    Full Text Available Abstract Background The UVB component of solar ultraviolet irradiation is one of the major risk factors for the development of skin cancer in humans. UVB exposure elicits an increased generation of reactive oxygen species (ROS, which are responsible for oxidative damage to proteins, DNA, RNA and lipids. In order to examine the biological impact of UVB irradiation on skin cells, we used a parallel proteomics approach to analyze the protein expression profile and to identify oxidatively modified proteins in normal human epithelial keratinocytes. Results The expression levels of fifteen proteins - involved in maintaining the cytoskeleton integrity, removal of damaged proteins and heat shock response - were differentially regulated in UVB-exposed cells, indicating that an appropriate response is developed in order to counteract/neutralize the toxic effects of UVB-raised ROS. On the other side, the redox proteomics approach revealed that seven proteins - involved in cellular adhesion, cell-cell interaction and protein folding - were selectively oxidized. Conclusions Despite a wide and well orchestrated cellular response, a relevant oxidation of specific proteins concomitantly occurs in UVB-irradiated human epithelial Keratinocytes. These modified (i.e. likely dysfunctional proteins might result in cell homeostasis impairment and therefore eventually promote cellular degeneration, senescence or carcinogenesis.

  14. Wedelolactone mitigates UVB induced oxidative stress, inflammation and early tumor promotion events in murine skin: plausible role of NFkB pathway.

    Science.gov (United States)

    Ali, Farrah; Khan, Bilal Azhar; Sultana, Sarwat

    2016-09-05

    UVB (Ultra-violet B) radiation is one of the major etiological factors in various dermal pathology viz. dermatitis, actinic folliculitis, solar urticaria, psoriasis and cancer among many others. UVB causes toxic manifestation in tissues by inciting inflammatory and tumor promoting events. We have designed this study to assess the anti-inflammatory and anti-tumor promotion effect of Wedelolactone (WDL) a specific IKK inhibitor. Results indicate significant restoration of anti-oxidative enzymes due to WDL treatments. We also found that WDL was effective in mitigating inflammatory markers consisting of MPO (myeloperoxidase), Mast cells trafficking, Langerhans cells suppression and COX 2 expression up regulation due to UVB exposure. We also deduce that WDL presented a promising intervention in attenuating early tumor promotion events caused by UVB exposure as indicated by the results of ODC (Ornithine Decarboxylase), Thymidine assay, Vimentin and VEGF (Vascular-endothelial growth factor) expression. This study was able to provide substantial cues for the therapeutic ability of Wedelolactone against inflammatory and tumor promoting events in murine skin depicting plausible role of NFkB pathway.

  15. Fatty acid desaturation in the marine prasinophyte Tetraselmis sp.: A sensitive indice of UV-B induced stress in marine phytoplankton

    Digital Repository Service at National Institute of Oceanography (India)

    Goes, J.I.; Handa, N.; Taguchi, S.; Hama, T.

    stream_size 10 stream_content_type text/plain stream_name Int_Symp_Ecophysiol_Photosyn_Cultures_Proc_1993_63.pdf.txt stream_source_info Int_Symp_Ecophysiol_Photosyn_Cultures_Proc_1993_63.pdf.txt Content-Encoding ISO-8859-1 Content...

  16. Metabolite profiling of enzymatically hydrolyzed and fermented forms of Opuntia ficus-indica and their effect on UVB-induced skin photoaging.

    Science.gov (United States)

    Cho, Dong-Woon; Kim, Dae-Eung; Lee, Dae-Hee; Jung, Kyung-Hoon; Hurh, Byung-Serk; Kwon, Oh Wook; Kim, Sun Yeou

    2014-01-01

    Fermentation of natural products is emerging as an important processing method and is attracting a lot of attention because it may have the advantage of having a new biological function. In this study, fruits of Opuntia ficus-indica were enzymatically hydrolyzed and then fermented with two species of yeast. We identified novel prominent markers in enzymatically hydrolyzed O. ficus-indica (EO) and fermented O. ficus-indica (FO) samples by using an ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry. We also evaluated the effect of EO and FO on photoaging of skin cells exposed to ultraviolet radiation. We identified the major fermented metabolite in the FO as ferulic acid. Our in vitro study indicated that FO significantly enhanced the concentration of pro-collagen type 1 than the EO, by increasing the TGF-β1 production.

  17. Loss of Keratinocytic RXRα Combined with Activated CDK4 or oncogenic NRAS Generates UVB-induced Melanomas via Loss of p53 and PTEN in the Tumor Microenvironment

    OpenAIRE

    Coleman, Daniel J.; Chagani, Sharmeen; Hyter, Stephen; Sherman, Anna M.; Löhr, Christiane V.; Liang, Xiaobo; Ganguli-Indra, Gitali; Indra, Arup K.

    2014-01-01

    Understanding the molecular mechanisms behind formation of melanoma, the deadliest form of skin cancer, is crucial for improved diagnosis and treatment. One key is to better understand the cross-talk between epidermal keratinocytes and pigment-producing melanocytes. Here, using a bigenic mouse model system combining mutant oncogenic NRASQ61K (constitutively active RAS) or mutant activated CDK4R24C/R24C (prevents binding of CDK4 by kinase inhibitor p16INK4A) with an epidermis-specific knockout...

  18. Vanillin protects human keratinocyte stem cells against ultraviolet B irradiation.

    Science.gov (United States)

    Lee, Jienny; Cho, Jae Youl; Lee, Sang Yeol; Lee, Kyung-Woo; Lee, Jongsung; Song, Jae-Young

    2014-01-01

    Ultraviolet-B (UVB) irradiation is one of major factors which induce cellular damages in the epidermis. We investigated protective effects and mechanisms of vanillin, a main constituent of vanilla beans, against UVB-induced cellular damages in keratinocyte stem cells (KSC). Here, vanillin significantly attenuated UVB irradiation-induced cytotoxicity. The vanillin effects were also demonstrated by the results of the senescence-associated β-galactosidase and alkaline comet assays. In addition, vanillin induced production of pro-inflammatory cytokines. Attempts to elucidate a possible mechanism underlying the vanillin-mediated effects revealed that vanillin significantly reduced UVB-induced phosphorylation of ataxia telangiectasia mutated (ATM), serine threonine kinase checkpoint kinase 2 (Chk2), tumor suppressor protein 53 (p53), p38/mitogen-activated protein kinase (p38), c-Jun N-terminal kinase/stress-activated protein kinase (JNK), S6 ribosomal protein (S6RP), and histone 2A family member X (H2A.X). UVB-induced activation of p53 luciferase reporter was also significantly inhibited by vanillin. In addition, while ATM inhibitor had no effect on the vanillin effects, mouse double minute 2 homolog (MDM2) inhibitor significantly attenuated suppressive effects of vanillin on UVB-induced activation of p53 reporter in KSC. Taken together, these findings suggest that vanillin protects KSC from UVB irradiation and its effects may occur through the suppression of downstream step of MDM2 in UVB irradiation-induced p53 activation.

  19. Lateral inhibition during nociceptive processing.

    Science.gov (United States)

    Quevedo, Alexandre S; Mørch, Carsten Dahl; Andersen, Ole K; Coghill, Robert C

    2017-06-01

    Spatial summation of pain (SSP) is the increase of perceived intensity that occurs as the stimulated area increases. Spatial summation of pain is subadditive in that increasing the stimulus area produces a disproportionately small increase in the perceived intensity of pain. A possible explanation for subadditive summation may be that convergent excitatory information is modulated by lateral inhibition. To test the hypothesis that lateral inhibition may limit SSP, we delivered different patterns of noxious thermal stimuli to the abdomens of 15 subjects using a computer-controlled CO2 laser. Lines (5 mm wide) of variable lengths (4, 8 cm) were compared with 2-point stimuli delivered at the same position/separation as the length of lines. When compared with one-point control stimuli, 2-point stimulus patterns produced statistically significant SSP, while no such summation was detected during line stimulus patterns. Direct comparison of pain intensity evoked by 2-point pattern stimuli with line pattern stimuli revealed that 2-point patterns were perceived as significantly more painful, despite the fact that the 2-point pattern stimulated far smaller areas of skin. Thus, the stimulation of the skin region between the endpoints of the lines appears to produce inhibition. These findings indicate that lateral inhibition limits SSP and is an intrinsic component of nociceptive information processing. Disruption of such lateral inhibition may contribute substantially to the radiation of some types of chronic pain.

  20. Activated sludge inhibition capacity index

    Directory of Open Access Journals (Sweden)

    V. Surerus

    2014-06-01

    Full Text Available Toxic compounds in sewage or industrial wastewater may inhibit the biological activity of activated sludge impairing the treatment process. This paper evaluates the Inhibition Capacity Index (ICI for the assessment of activated sludge in the presence of toxicants. In this study, activated sludge was obtained from industrial treatment plants and was also synthetically produced. Continuous respirometric measurements were carried out in a reactor, and the oxygen uptake rate profile obtained was used to evaluate the impact of inhibiting toxicants, such as dissolved copper, phenol, sodium alkylbenzene sulfonate and amoxicillin, on activated sludge. The results indicate that ICI is an efficient tool to quantify the intoxication capacity. The activated sludge from the pharmaceutical industry showed higher resistance than the sludge from other sources, since toxicants are widely discharged in the biological treatment system. The ICI range was from 58 to 81% when compared to the synthetic effluent with no toxic substances.

  1. Homo economicus belief inhibits trust.

    Directory of Open Access Journals (Sweden)

    Ziqiang Xin

    Full Text Available As a foundational concept in economics, the homo economicus assumption regards humans as rational and self-interested actors. In contrast, trust requires individuals to believe partners' benevolence and unselfishness. Thus, the homo economicus belief may inhibit trust. The present three experiments demonstrated that the direct exposure to homo economicus belief can weaken trust. And economic situations like profit calculation can also activate individuals' homo economicus belief and inhibit their trust. It seems that people's increasing homo economicus belief may serve as one cause of the worldwide decline of trust.

  2. Homo economicus belief inhibits trust.

    Science.gov (United States)

    Xin, Ziqiang; Liu, Guofang

    2013-01-01

    As a foundational concept in economics, the homo economicus assumption regards humans as rational and self-interested actors. In contrast, trust requires individuals to believe partners' benevolence and unselfishness. Thus, the homo economicus belief may inhibit trust. The present three experiments demonstrated that the direct exposure to homo economicus belief can weaken trust. And economic situations like profit calculation can also activate individuals' homo economicus belief and inhibit their trust. It seems that people's increasing homo economicus belief may serve as one cause of the worldwide decline of trust.

  3. Strigolactone inhibition of shoot branching

    NARCIS (Netherlands)

    Gomez-Roldan, M.V.; Fermas, S.; Brewer, P.B.; Puech-Pages, V.; Dun, E.A.; Pillot, J.P.; Letisse, F.; Matusova, R.; Danoun, S.; Portais, J.C.; Bouwmeester, H.J.; Becard, G.; Beveridge, C.A.; Rameau, C.; Rochange, S.F.

    2008-01-01

    A carotenoid-derived hormonal signal that inhibits shoot branching in plants has long escaped identification. Strigolactones are compounds thought to be derived from carotenoids and are known to trigger the germination of parasitic plant seeds and stimulate symbiotic fungi. Here we present evidence

  4. Strigolactone inhibition of shoot branching

    NARCIS (Netherlands)

    Gomez-Roldan, M.V.; Fermas, S.; Brewer, P.B.; Puech-Pages, V.; Dun, E.A.; Pillot, J.P.; Letisse, F.; Matusova, R.; Danoun, S.; Portais, J.C.; Bouwmeester, H.J.; Becard, G.; Beveridge, C.A.; Rameau, C.; Rochange, S.F.

    2008-01-01

    A carotenoid-derived hormonal signal that inhibits shoot branching in plants has long escaped identification. Strigolactones are compounds thought to be derived from carotenoids and are known to trigger the germination of parasitic plant seeds and stimulate symbiotic fungi. Here we present evidence

  5. Methanogenic inhibition by arsenic compounds.

    Science.gov (United States)

    Sierra-Alvarez, Reyes; Cortinas, Irail; Yenal, Umur; Field, Jim A

    2004-09-01

    The acute acetoclastic methanogenic inhibition of several inorganic and organic arsenicals was assayed. Trivalent species, i.e., methylarsonous acid and arsenite, were highly inhibitory, with 50% inhibitory concentrations of 9.1 and 15.0 microM, respectively, whereas pentavalent species were generally nontoxic. The nitrophenylarsonate derivate, roxarsone, displayed moderate toxicity.

  6. Inhibition of carcinogenesis by tea.

    Science.gov (United States)

    Yang, Chung S; Maliakal, Pius; Meng, Xiaofeng

    2002-01-01

    Tea has received a great deal of attention because tea polyphenols are strong antioxidants, and tea preparations have inhibitory activity against tumorigenesis. The bioavailability and biotransformation of tea polyphenols, however, are key factors limiting these activities in vivo. The inhibition of tumorigenesis by green or black tea preparations has been demonstrated in animal models on different organ sites such as skin, lung, oral cavity, esophagus, forestomach, stomach, small intestine, colon, pancreas, and mammary gland. Epidemiological studies, however, have not yielded clear conclusions concerning the protective effects of tea consumption against cancer formation in humans. The discrepancy between the results from humans and animal models could be due to 1) the much higher doses of tea used in animals in comparison to human consumption, 2) the differences in causative factors between the cancers in humans and animals, and 3) confounding factors limiting the power of epidemiological studies to detect an effect. It is possible that tea may be only effective against specific types of cancer caused by certain etiological factors. Many mechanisms have been proposed for the inhibition of carcinogenesis by tea, including the modulation of signal transduction pathways that leads to the inhibition of cell proliferation and transformation, induction of apoptosis of preneoplastic and neoplastic cells, as well as inhibition of tumor invasion and angiogenesis. These mechanisms need to be evaluated and verified in animal models or humans in order to gain more understanding on the effect of tea consumption on human cancer.

  7. Testing of Biologically Inhibiting Surface

    DEFF Research Database (Denmark)

    Bill Madsen, Thomas; Larsen, Erup

    2003-01-01

    The main purpose of this course is to examine a newly developed biologically inhibiting material with regards to galvanic corrosion and electrochemical properties. More in detail, the concern was how the material would react when exposed to cleaning agents, here under CIP cleaning (Cleaning...

  8. Islam Does Not Inhibit Science.

    Science.gov (United States)

    Shanavas, T. O.

    1999-01-01

    Compares the science/religion relationship in both Christian and Islamic countries. Presents Muslim scholars' ideas about the presence of humans on earth. Presents ideas on active nature, Noah's curse, and the age of the universe. Refutes the notion that Islam inhibited science and advocates the belief that Islam promoted science. (YDS)

  9. Epigallocatechin gallate inhibits endothelial exocytosis.

    Science.gov (United States)

    Yamakuchi, Munekazu; Bao, Clare; Ferlito, Marcella; Lowenstein, Charles J

    2008-07-01

    Consumption of green tea is associated with a decrease in cardiovascular mortality. The beneficial health effects of green tea are attributed in part to polyphenols, organic compounds found in tea that lower blood pressure, reduce body fat, decrease LDL cholesterol, and inhibit inflammation. We hypothesized that epigallocatechin gallate (EGCG), the most abundant polyphenol in tea, inhibits endothelial exocytosis, the initial step in leukocyte trafficking and vascular inflammation. To test this hypothesis, we treated human umbilical-vein endothelial cells with EGCG and other polyphenols, and then measured endothelial exocytosis. We found that EGCG decreases endothelial exocytosis in a concentration-dependent manner, with the effects most prominent after 4 h of treatment. Other catechin polyphenols had no effect on endothelial cells. By inhibiting endothelial exocytosis, EGCG decreases leukocyte adherence to endothelial cells. In searching for the mechanism by which EGCG affects endothelial cells, we found that EGCG increases Akt phosphorylation, eNOS phosphorylation, and nitric oxide (NO) production. NOS inhibition revealed that NO mediates the anti-inflammatory effects of EGCG. Our data suggest that polyphenols can decrease vascular inflammation by increasing the synthesis of NO, which blocks endothelial exocytosis.

  10. Infant Predictors of Behavioural Inhibition

    Science.gov (United States)

    Moehler, Eva; Kagan, Jerome; Oelkers-Ax, Rieke; Brunner, Romuald; Poustka, Luise; Haffner, Johann; Resch, Franz

    2008-01-01

    Behavioural inhibition in the second year of life is a hypothesized predictor for shyness, social anxiety and depression in later childhood, adolescence and even adulthood. To search for the earliest indicators of this fundamental temperamental trait, this study examined whether behavioural characteristics in early infancy can predict behavioural…

  11. Corrosion Chemistry in Inhibited HDA.

    Science.gov (United States)

    1980-11-30

    Titanium and chromium have sufficiently low Flade potentials to pass- ivate in non-oxidising acids, but Iron will only exhibit self-passivity if the...inhibition e.g. involving organic and pickling inhibitors* the rest potential can actually 4.5,4.6become more negative " This is due to cathodic rather...media. 321 stainless steel, titanium stabilised, was the particular steel studied, being very similar in composition to the 347also stainless steel

  12. Notch Signaling Inhibits Axon Regeneration

    OpenAIRE

    Bejjani, Rachid El; Hammarlund, Marc

    2012-01-01

    Many neurons have limited capacity to regenerate their axons after injury. Neurons in the mammalian CNS do not regenerate, and even neurons in the PNS often fail to regenerate to their former targets. This failure is likely due in part to pathways that actively restrict regeneration; however, only a few factors that limit regeneration are known. Here, using single-neuron analysis of regeneration in vivo, we show that Notch/lin-12 signaling inhibits the regeneration of mature C. elegans neuron...

  13. Th2 cytokines inhibit lymphangiogenesis.

    Directory of Open Access Journals (Sweden)

    Ira L Savetsky

    Full Text Available Lymphangiogenesis is the process by which new lymphatic vessels grow in response to pathologic stimuli such as wound healing, inflammation, and tumor metastasis. It is well-recognized that growth factors and cytokines regulate lymphangiogenesis by promoting or inhibiting lymphatic endothelial cell (LEC proliferation, migration and differentiation. Our group has shown that the expression of T-helper 2 (Th2 cytokines is markedly increased in lymphedema, and that these cytokines inhibit lymphatic function by increasing fibrosis and promoting changes in the extracellular matrix. However, while the evidence supporting a role for T cells and Th2 cytokines as negative regulators of lymphatic function is clear, the direct effects of Th2 cytokines on isolated LECs remains poorly understood. Using in vitro and in vivo studies, we show that physiologic doses of interleukin-4 (IL-4 and interleukin-13 (IL-13 have profound anti-lymphangiogenic effects and potently impair LEC survival, proliferation, migration, and tubule formation. Inhibition of these cytokines with targeted monoclonal antibodies in the cornea suture model specifically increases inflammatory lymphangiogenesis without concomitant changes in angiogenesis. These findings suggest that manipulation of anti-lymphangiogenic pathways may represent a novel and potent means of improving lymphangiogenesis.

  14. Conditioned inhibition and reinforcement rate.

    Science.gov (United States)

    Harris, Justin A; Kwok, Dorothy W S; Andrew, Benjamin J

    2014-07-01

    We investigated conditioned inhibition in a magazine approach paradigm. Rats were trained on a feature negative discrimination between an auditory conditioned stimulus (CS) reinforced at one rate versus a compound of that CS and a visual stimulus (L) reinforced at a lower rate. This training established L as a conditioned inhibitor. We then tested the inhibitory strength of L by presenting it in compound with other auditory CSs. L reduced responding when tested with a CS that had been reinforced at a high rate, but had less or even no inhibitory effect when tested with a CS that had been reinforced at a low rate. The inhibitory strength of L was greater if it signaled a decrease in reinforcement from an already low rate than if it signaled an equivalent decrease in reinforcement from a high rate. We conclude that the strength of inhibition is not a linear function of the change in reinforcement that it signals. We discuss the implications of this finding for models of learning (e.g., Rescorla & Wagner, 1972) that identify inhibition with a difference (subtraction) rule.

  15. Grape seed proanthocyanidines and skin cancer prevention: inhibition of oxidative stress and protection of immune system.

    Science.gov (United States)

    Katiyar, Santosh K

    2008-06-01

    Overexposure of the skin to UV radiation has a variety of adverse effects on human health, including the development of skin cancers. There is a need to develop nutrition-based efficient chemopreventive strategies. The proanthocyanidins present in grape seeds (Vitis vinifera) have been shown to have some biological effects, including prevention of photocarcinogenesis. The present communication discusses the in vitro and in vivo studies of the possible protective effect of grape seed proanthocyanidins (GSPs) and the molecular mechanism for these effects. In SKH-1 hairless mice, dietary supplementation with GSPs is associated with a decrease of UVB-induced skin tumor development in terms of tumor incidence, tumor multiplicity, and a decrease in the malignant transformation of papillomas to carcinomas. It is suggested that the chemopreventive effects of dietary GSPs are mediated through the attenuation of UV-induced: (i) oxidative stress; (ii) activation of mitogen-activated protein kinases and nuclear factor-kappa B (NF-kappaB) signaling pathways; and (iii) immunosuppression through alterations in immunoregulatory cytokines. Collectively, these studies indicate protective potential of GSPs against experimental photocarcinogenesis in SKH-1 hairless mice, and the possible mechanisms of action of GSPs, and suggest that dietary GSPs could be useful in the attenuation of the adverse UV-induced health effects in human skin.

  16. Glycyrrhizic acid (GA) inhibits reactive oxygen Species mediated photodamage by blocking ER stress and MAPK pathway in UV-B irradiated human skin fibroblasts.

    Science.gov (United States)

    Farrukh, Mufti Rana; Nissar, Ul-Ashraf; Kaiser, Peerzada J; Afnan, Quadri; Sharma, Praduman R; Bhushan, Shashi; Tasduq, Sheikh A

    2015-07-01

    Previously we have reported that generation of reactive oxygen species is the prime event responsible for calcium mediated activation of PERK-eIF2α-CHOP pathway and apoptosis in UV-B irradiated human skin fibroblasts (Hs68). We have also reported that glycyrrhizic acid (GA) mediates potent photoprotective activity against UV-B - irradiation-induced photodamage in human skin fibroblast. In the present study, we aimed to investigate the role of GA in preventing oxidative stress mediated unfolded protein response (UPR) and mitogen activated protein kinases (MAPK) pathway. Human skin fibroblast (Hs68) cells were exposed to UV-B radiations in lab conditions. Different parameters of UVB induced cellular and molecular changes were analysed using western-blotting, microscopy and flow cytometry. Our results show that GA has strong photoprotective action against UV-B induced cellular damage. It was observed that: (a) Oxidative disturbances and intracellular Ca(2+) imbalance induced by UV-B irradiation was significantly restored by GA treatment; (b) activation of PERK-eIF2α-CHOP and MAPK pathway induced by UV-B was significantly blocked by GA; (c) Loss of mitochondrial membrane potential and apoptosis induced by UV-B were reduced by GA treatment. Based on the above findings we conclude GA has a highly significant ROS quenching activity, thereby blocking the cascade of events including release of calcium from ER and subsequent ER stress, MAPK pathway and cellular demise. GA offers highly potent anti photodamage effect and can be exploited for cosmetic or therapeutic purposes. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Self-regulation, ego depletion, and inhibition.

    Science.gov (United States)

    Baumeister, Roy F

    2014-12-01

    Inhibition is a major form of self-regulation. As such, it depends on self-awareness and comparing oneself to standards and is also susceptible to fluctuations in willpower resources. Ego depletion is the state of reduced willpower caused by prior exertion of self-control. Ego depletion undermines inhibition both because restraints are weaker and because urges are felt more intensely than usual. Conscious inhibition of desires is a pervasive feature of everyday life and may be a requirement of life in civilized, cultural society, and in that sense it goes to the evolved core of human nature. Intentional inhibition not only restrains antisocial impulses but can also facilitate optimal performance, such as during test taking. Self-regulation and ego depletion- may also affect less intentional forms of inhibition, even chronic tendencies to inhibit. Broadly stated, inhibition is necessary for human social life and nearly all societies encourage and enforce it.

  18. Reflex excitability regulates prepulse inhibition.

    Science.gov (United States)

    Schicatano, E J; Peshori, K R; Gopalaswamy, R; Sahay, E; Evinger, C

    2000-06-01

    Presentation of a weak stimulus, a prepulse, before a reflex-evoking stimulus decreases the amplitude of the reflex response relative to reflex amplitude evoked without a preceding prepulse. For example, presenting a brief tone before a trigeminal blink-eliciting stimulus significantly reduces reflex blink amplitude. A common explanation of such data are that sensory processing of the prepulse modifies reflex circuit behavior. The current study investigates the converse hypothesis that the intrinsic characteristics of the reflex circuit rather than prepulse processing determine prepulse modification of trigeminal and acoustic reflex blinks. Unilateral lesions of substantia nigra pars compacta neurons created rats with hyperexcitable trigeminal reflex blinks but normally excitable acoustic reflex blinks. In control rats, presentation of a prepulse reduced the amplitude of both trigeminal and acoustic reflex blinks. In 6-OHDA-lesioned rats, however, the same acoustic prepulse facilitated trigeminal reflex blinks but inhibited acoustic reflex blinks. The magnitude of prepulse modification correlated with reflex excitability. Humans exhibited the same pattern of prepulse modification. An acoustic prepulse facilitated the trigeminal reflex blinks of subjects with hyperexcitable trigeminal reflex blinks caused by Parkinson's disease. The same prepulse inhibited trigeminal reflex blinks of age-matched control subjects. Prepulse modification also correlated with trigeminal reflex blink excitability. These data show that reflex modification by a prepulse reflects the intrinsic characteristics of the reflex circuit rather than an external adjustment of the reflex circuit by the prepulse.

  19. Graphene: corrosion-inhibiting coating.

    Science.gov (United States)

    Prasai, Dhiraj; Tuberquia, Juan Carlos; Harl, Robert R; Jennings, G Kane; Rogers, Bridget R; Bolotin, Kirill I

    2012-02-28

    We report the use of atomically thin layers of graphene as a protective coating that inhibits corrosion of underlying metals. Here, we employ electrochemical methods to study the corrosion inhibition of copper and nickel by either growing graphene on these metals, or by mechanically transferring multilayer graphene onto them. Cyclic voltammetry measurements reveal that the graphene coating effectively suppresses metal oxidation and oxygen reduction. Electrochemical impedance spectroscopy measurements suggest that while graphene itself is not damaged, the metal under it is corroded at cracks in the graphene film. Finally, we use Tafel analysis to quantify the corrosion rates of samples with and without graphene coatings. These results indicate that copper films coated with graphene grown via chemical vapor deposition are corroded 7 times slower in an aerated Na(2)SO(4) solution as compared to the corrosion rate of bare copper. Tafel analysis reveals that nickel with a multilayer graphene film grown on it corrodes 20 times slower while nickel surfaces coated with four layers of mechanically transferred graphene corrode 4 times slower than bare nickel. These findings establish graphene as the thinnest known corrosion-protecting coating.

  20. A Combination of Soybean and Haematococcus Extract Alleviates Ultraviolet B-Induced Photoaging

    Science.gov (United States)

    Shin, Jieun; Kim, Jong-Eun; Pak, Kum-Ju; Kang, Jung Il; Kim, Tae-Seok; Lee, Sang-Yoon; Yeo, Ik-Hyun; Park, Jung Han Yoon; Kim, Jong Hun; Kang, Nam Joo; Lee, Ki Won

    2017-01-01

    Soybean-derived isoflavones have been investigated for their preventative effects against UV-induced symptoms of skin damage including wrinkle formation and inflammation. Haematococcus pluvialis is a freshwater species of Chlorophyta that contains high concentrations of the natural carotenoid pigment astaxanthin. Astaxanthin is known to be involved in retinoic acid receptor (RAR) signaling and previously been associated with the inhibition of activator protein (AP)-1 dependent transcription. Based on previous studies, we hypothesized that a combination of soy extract (SE) and Haematococcus extract (HE) may prevent UVB-induced photoaging through specific signaling pathways, as measured by UVB-induced wrinkling on hairless mice skin and expression changes in human dermal fibroblasts (HDFs). The 1:2 ratio of SE and HE mixture (SHM) showed the optimal benefit in vivo. SHM was found to inhibit wrinkle formation via the downregulation of matrix metalloproteinase (MMP)-1 mRNA and protein expression. SHM also inhibited mitogen-activated protein kinase (MAPK) phosphorylation and the transactivation of AP-1 which plays an important role in regulating MMP expression. These results highlight the potential for SHM to be developed as a therapeutic agent to prevent UVB-induced skin wrinkling. PMID:28327532

  1. Greener Approach towards Corrosion Inhibition

    Directory of Open Access Journals (Sweden)

    Neha Patni

    2013-01-01

    Full Text Available Corrosion control of metals is technically, economically, environmentally, and aesthetically important. The best option is to use inhibitors for protecting metals and alloys against corrosion. As organic corrosion inhibitors are toxic in nature, so green inhibitors which are biodegradable, without any heavy metals and other toxic compounds, are promoted. Also plant products are inexpensive, renewable, and readily available. Tannins, organic amino acids, alkaloids, and organic dyes of plant origin have good corrosion-inhibiting abilities. Plant extracts contain many organic compounds, having polar atoms such as O, P, S, and N. These are adsorbed on the metal surface by these polar atoms, and protective films are formed, and various adsorption isotherms are obeyed. Various types of green inhibitors and their effect on different metals are mentioned in the paper.

  2. Inhibiting scale in oil wells

    Energy Technology Data Exchange (ETDEWEB)

    D' Errico, M.J.; Adler, S.F.

    1972-09-27

    An oil well treatment is described to inhibit the formation of hard scale by precipitation from the oil well brine of scale-forming water insoluble sulfate, carbonate, and other salts. The process consists of incorporating into the oil well during a fracturing treatment, a fluid containing a solid polymeric material characterized by molecular weight in the range of 1,000 to 15,000 and a substantially linear structure, derived by the linear polymerization of at least one monoolefinically unsaturated compound through the olefinically unsaturated group. The linear structure has pendent groups, 50% of which are carboxy groups, the carboxy groups being neutralized with a sufficient proportion of at least one compound having a cation of a metal selected from alkaline earth metals, chromium, aluminum, iron, cobalt, zinc, nickel or copper to render the polymer soluble in water at 25$C to a concentration of not more than 50 ppm. (8 claims)

  3. Anti-Inflammatory Effects of Agrimoniin-Enriched Fractions of Potentilla erecta

    Directory of Open Access Journals (Sweden)

    Julia Hoffmann

    2016-06-01

    Full Text Available Potentilla erecta (PE is a small herbaceous plant with four yellow petals belonging to the Rosaceae family. The rhizome of PE has traditionally been used as an antidiarrheal, hemostatic and antihemorrhoidal remedy. PE contains up to 20% tannins and 5% ellagitannins, mainly agrimoniin. Agrimoniin is a hydrolyzable tannin that is a potent radical scavenger. In this study we tested the anti-inflammatory effect of four PE fractions with increasing amounts of agrimoniin obtained by Sephadex column separation. First, we analyzed in HaCaT keratinocytes the expression of cyclooxygenase-2 (COX-2 induced by ultraviolet-B (UVB irradiation. As COX-2 catalyzes the metabolism of arachidonic acid to prostanoids such as PGE2, we also measured the PGE2 concentration in cell culture supernatants. PE inhibited UVB-induced COX-2 expression in HaCaT cells and dose-dependently reduced PGE2. The PE fraction with the highest agrimoniin amount (PE4 was the most effective in this experiment, whereas fraction PE1 containing mainly sugars had no effect. PE4 also dose dependently inhibited the phosphorylation of the epidermal growth factor receptor (EGFR which plays a crucial role in UVB-mediated COX-2 upregulation. A placebo-controlled UV-erythema study with increasing concentrations of PE4 demonstrated a dose dependent inhibition of UVB-induced inflammation in vivo. Similarly, PE4 significantly reduced UVB-induced PGE2 production in suction blister fluid in vivo. In summary, PE fractions with a high agrimoniin content display anti-inflammatory effects in vitro and in vivo in models of UVB-induced inflammation.

  4. Anti-Inflammatory Effects of Agrimoniin-Enriched Fractions of Potentilla erecta.

    Science.gov (United States)

    Hoffmann, Julia; Casetti, Federica; Bullerkotte, Ute; Haarhaus, Birgit; Vagedes, Jan; Schempp, Christoph M; Wölfle, Ute

    2016-06-18

    Potentilla erecta (PE) is a small herbaceous plant with four yellow petals belonging to the Rosaceae family. The rhizome of PE has traditionally been used as an antidiarrheal, hemostatic and antihemorrhoidal remedy. PE contains up to 20% tannins and 5% ellagitannins, mainly agrimoniin. Agrimoniin is a hydrolyzable tannin that is a potent radical scavenger. In this study we tested the anti-inflammatory effect of four PE fractions with increasing amounts of agrimoniin obtained by Sephadex column separation. First, we analyzed in HaCaT keratinocytes the expression of cyclooxygenase-2 (COX-2) induced by ultraviolet-B (UVB) irradiation. As COX-2 catalyzes the metabolism of arachidonic acid to prostanoids such as PGE₂, we also measured the PGE₂ concentration in cell culture supernatants. PE inhibited UVB-induced COX-2 expression in HaCaT cells and dose-dependently reduced PGE₂. The PE fraction with the highest agrimoniin amount (PE4) was the most effective in this experiment, whereas fraction PE1 containing mainly sugars had no effect. PE4 also dose dependently inhibited the phosphorylation of the epidermal growth factor receptor (EGFR) which plays a crucial role in UVB-mediated COX-2 upregulation. A placebo-controlled UV-erythema study with increasing concentrations of PE4 demonstrated a dose dependent inhibition of UVB-induced inflammation in vivo. Similarly, PE4 significantly reduced UVB-induced PGE₂ production in suction blister fluid in vivo. In summary, PE fractions with a high agrimoniin content display anti-inflammatory effects in vitro and in vivo in models of UVB-induced inflammation.

  5. Latent inhibition in human adults without masking.

    Science.gov (United States)

    Escobar, Martha; Arcediano, Francisco; Miller, Ralph R

    2003-09-01

    Latent inhibition refers to attenuated responding to Cue X observed when the X-outcome pairings are preceded by X-alone presentations. It has proven difficult to obtain in human adults unless the preexposure (X-alone) presentations are embedded within a masking (i.e., distracting) task. The authors hypothesized that the difficulty in obtaining latent inhibition with unmasked tasks is related to the usual training procedures, in which the preexposure and conditioning experiences are separated by a set of instructions. Experiment 1 reports latent inhibition without masking in a task in which preexposure and conditioning occur without interruption. Experiments 2 and 3 demonstrate that this attenuation in responding to target Cue X does not pass a summation test for conditioned inhibition and is context specific, thereby confirming that it is latent inhibition. Experiments 3 and 4 confirm that introducing instructions between preexposure and conditioning disrupts latent inhibition.

  6. Enhanced latent inhibition in high schizotypy individuals

    OpenAIRE

    Granger, Kiri T.; Moran, Paula M.; Buckley, Matthew G.; Haselgrove, Mark

    2016-01-01

    Latent inhibition refers to a retardation in learning about a stimulus that has been rendered familiar by non-reinforced preexposure, relative to a non-preexposed stimulus. Latent inhibition has been shown to be inversely correlated with schizotypy, and abnormal in people with schizophrenia, but these findings are inconsistent. One potential contributing factor to this inconsistency is that many tasks that purport to measure latent inhibition are confounded by alternative effects that also re...

  7. Collaborative inhibition in spatial memory retrieval

    National Research Council Canada - National Science Library

    Sjolund, Lori A; Erdman, Matthew; Kelly, Jonathan W

    2014-01-01

    .... Two experiments were designed to explore whether collaborative inhibition, which has heretofore been studied using traditional memory stimuli such as word lists, also characterizes spatial memory retrieval...

  8. Inhibition of the dorsal premotor cortex does not repair surround inhibition in writer's cramp patients.

    Science.gov (United States)

    Veugen, Lidwien C; Hoffland, Britt S; Stegeman, Dick F; van de Warrenburg, Bart P

    2013-03-01

    Writer's cramp is a task-specific form of focal dystonia, characterized by abnormal movements and postures of the hand and arm during writing. Two consistent abnormalities in its pathophysiology are a loss of surround inhibition and overactivity of the dorsal premotor cortex (PMd). This study aimed to assess a possible link between these two phenomena by investigating whether PMd inhibition leads to an improvement of surround inhibition, in parallel with previously demonstrated writing improvement. Fifteen writer's cramp patients and ten controls performed a simple motor hand task during which surround inhibition was measured using transcranial magnetic stimulation. Motor cortical excitability was measured of the active and surround muscles at three phases of the task. Surround inhibition and writing performance were assessed before and after PMd inhibitory continuous theta burst stimulation. In contrast to healthy controls, patients did not show inhibition of the abductor digiti minimi muscle during movement initiation of the first dorsal interosseus muscle, confirming the loss of surround inhibition. PMd inhibition led to an improvement of writing speed in writer's cramp patients. However, in both groups, no changes in surround inhibition were observed. The results confirm a role for the PMd in the pathophysiology of writer's cramp. We show that PMd inhibition does not lead to restoration of the surround inhibition defect in writer's cramp, despite the improvement in writing. This questions the involvement of the PMd in the loss of surround inhibition, and perhaps also the direct link between surround inhibition and dystonia.

  9. Reduced surround inhibition in musicians.

    Science.gov (United States)

    Shin, Hae-Won; Kang, Suk Y; Hallett, Mark; Sohn, Young H

    2012-06-01

    To investigate whether surround inhibition (SI) in the motor system is altered in professional musicians, we performed a transcranial magnetic stimulation (TMS) study in 10 professional musicians and 15 age-matched healthy non-musicians. TMS was set to be triggered by self-initiated flexion of the index finger at different intervals ranging from 3 to 1,000 ms. Average motor evoked potential (MEP) amplitudes obtained from self-triggered TMS were normalized to average MEPs of the control TMS at rest and expressed as a percentage. Normalized MEP amplitudes of the abductor digiti minimi (ADM) muscles were compared between the musicians and non-musicians with the primary analysis being the intervals between 3 and 80 ms (during the movement). A mixed-design ANOVA revealed a significant difference in normalized ADM MEPs during the index finger flexion between groups, with less SI in the musicians. This study demonstrated that the functional operation of SI is less strong in musicians than non-musicians, perhaps due to practice of movement synergies involving both muscles. Reduced SI, however, could lead susceptible musicians to be prone to develop task-specific dystonia.

  10. Cellulase Inhibition by High Concentrations of Monosaccharides

    DEFF Research Database (Denmark)

    Hsieh, Chia-Wen; Cannella, David; Jørgensen, Henning

    2014-01-01

    that low free water availability contributes to cellulase inhibition. Of the hydrolytic enzymes involved, those acting on the cellulose substrate, that is, exo- and endoglucanases, were the most inhibited. The β -glucosidases were shown to be less sensitive to high monosaccharide concentrations except...

  11. A Qualitative Approach to Enzyme Inhibition

    Science.gov (United States)

    Waldrop, Grover L.

    2009-01-01

    Most general biochemistry textbooks present enzyme inhibition by showing how the basic Michaelis-Menten parameters K[subscript m] and V[subscript max] are affected mathematically by a particular type of inhibitor. This approach, while mathematically rigorous, does not lend itself to understanding how inhibition patterns are used to determine the…

  12. Inhibited and Uninhibited Types of Children.

    Science.gov (United States)

    Kagan, Jerome; And Others

    1989-01-01

    Investigates the preservation of inhibited and uninhibited behaviors in 100 children of 14, 20, 32, and 48 months. Children who had been extremely inhibited or uninhibited at 14 and 20 months differed significantly at 4 years of age in behavior and cardiac acceleration. (RJC)

  13. Inhibition: Mental Control Process or Mental Resource?

    Science.gov (United States)

    Im-Bolter, Nancie; Johnson, Janice; Ling, Daphne; Pascual-Leone, Juan

    2015-01-01

    The current study tested 2 models of inhibition in 45 children with language impairment and 45 children with normally developing language; children were aged 7 to 12 years. Of interest was whether a model of inhibition as a mental-control process (i.e., executive function) or as a mental resource would more accurately reflect the relations among…

  14. Quorum Sensing Inhibition, Relevance to Periodontics

    OpenAIRE

    Yada, Sudheer; Kamalesh, B; Sonwane, Siddharth; Guptha, Indra; Swetha, R K

    2015-01-01

    Quorum sensing helps bacteria to communicate with each other and in coordinating their behavior. Many diseases of human beings, plants, and animals are mediated by quorum sensing. Various approaches are being tried to inhibit this communication to control the diseases caused by bacteria. Periodontal pathogens also communicate through quorum sensing and new approaches to treat periodontal disease using quorum sensing inhibition need to explored.

  15. A Qualitative Approach to Enzyme Inhibition

    Science.gov (United States)

    Waldrop, Grover L.

    2009-01-01

    Most general biochemistry textbooks present enzyme inhibition by showing how the basic Michaelis-Menten parameters K[subscript m] and V[subscript max] are affected mathematically by a particular type of inhibitor. This approach, while mathematically rigorous, does not lend itself to understanding how inhibition patterns are used to determine the…

  16. Quorum sensing inhibition, relevance to periodontics.

    Science.gov (United States)

    Yada, Sudheer; Kamalesh, B; Sonwane, Siddharth; Guptha, Indra; Swetha, R K

    2015-01-01

    Quorum sensing helps bacteria to communicate with each other and in coordinating their behavior. Many diseases of human beings, plants, and animals are mediated by quorum sensing. Various approaches are being tried to inhibit this communication to control the diseases caused by bacteria. Periodontal pathogens also communicate through quorum sensing and new approaches to treat periodontal disease using quorum sensing inhibition need to explored.

  17. Nrf1 CNC-bZIP protein promotes cell survival and nucleotide excision repair through maintaining glutathione homeostasis.

    Science.gov (United States)

    Han, Weinong; Ming, Mei; Zhao, Rui; Pi, Jingbo; Wu, Chunli; He, Yu-Ying

    2012-05-25

    Skin cancer is the most common cancer in the United States. Its major environmental risk factor is UVB radiation in sunlight. In response to UVB damage, epidermal keratinocytes activate a specific repair pathway, i.e. nucleotide excision repair, to remove UVB-induced DNA lesions. However, the regulation of UVB response is not fully understood. Here we show that the long isoform of the nuclear factor erythroid 2-related factor 1 (Nrf1, also called NFE2L1), a cytoprotective transcription factor critical for the expression of multiple antioxidant response element-dependent genes, plays an important role in the response of keratinocytes to UVB. Nrf1 loss sensitized keratinocytes to UVB-induced apoptosis by up-regulating the expression of the proapoptotic Bcl-2 family member Bik through reducing glutathione levels. Knocking down Bik reduced UVB-induced apoptosis in Nrf1-inhibited cells. In UVB-irradiated surviving cells, however, disruption of Nrf1 impaired nucleotide excision repair through suppressing the transcription of xeroderma pigmentosum C (XPC), a factor essential for initiating the global genome nucleotide excision repair by recognizing the DNA lesion and recruiting downstream factors. Nrf1 enhanced XPC expression by increasing glutathione availability but was independent of the transcription repressor of XPC. Adding XPC or glutathione restored the DNA repair capacity in Nrf1-inhibited cells. Finally, we demonstrate that Nrf1 levels are significantly reduced by UVB radiation in mouse skin and are lower in human skin tumors than in normal skin. These results indicate a novel role of Nrf1 in UVB-induced DNA damage repair and suggest Nrf1 as a tumor suppressor in the skin.

  18. Inhibition in Autism: Children with Autism Have Difficulty Inhibiting Irrelevant Distractors but Not Prepotent Responses

    Science.gov (United States)

    Adams, Nena C.; Jarrold, Christopher

    2012-01-01

    Resistance to distractor inhibition tasks have previously revealed impairments in children with autism. However, on the classic Stroop task and other prepotent response tasks, children with autism show intact inhibition. These data may reflect a distinction between prepotent response and resistance to distractor inhibition. The current study…

  19. Inhibition of ethylene production by rhizobitoxine

    Energy Technology Data Exchange (ETDEWEB)

    Owens, L.D.; Lieberman, M.; Kunishi, A.

    1970-01-01

    Rhizobitoxine, an inhibitor of methionine biosynthesis in Salmonella typhimurium, inhibited ethylene production about 75% in light-grown sorghum seedlings and in senescent apple tissue. Ethylene production stimulated by indoleacetic acid and kinetin in sorghum was similarly inhibited. With both apple and sorghum, the inhibition could only be partially relieved by additions of methionine. A methionine analogue, ..cap alpha..-keto-..gamma..-methylthiobutyric acid, which has been suggested as an intermediate between methionine and ethylene, had no effect on the inhibition. Incorporation of /sup 14/C from added methionine-/sup 14/C into ethylene was curtailed by rhizobitoxine to about the same extent as was ethylene production. These results suggest that rhizobitoxine interferes with ethylene biosynthesis by blocking the conversion of methionine to ethylene and not indirectly by inhibiting the biosynthesis of methionine. Ethylene production by Penicillium digitatum, a fungus which produces ethylene via pathways not utilizing methionine as a precursor, was not affected by rhizobitoxine. 16 references, 2 figures, 4 tables.

  20. Habituation, latent inhibition, and extinction.

    Science.gov (United States)

    Jordan, Wesley P; Todd, Travis P; Bucci, David J; Leaton, Robert N

    2015-06-01

    In two conditioned suppression experiments with a latent inhibition (LI) design, we measured the habituation of rats in preexposure, their LI during conditioning, and then extinction over days. In the first experiment, lick suppression, the preexposed group (PE) showed a significant initial unconditioned response (UR) to the target stimulus and significant long-term habituation (LTH) of that response over days. The significant difference between the PE and nonpreexposed (NPE) groups on the first conditioning trial was due solely to the difference in their URs to the conditioned stimulus (CS)-a habituated response (PE) and an unhabituated response (NPE). In the second experiment, bar-press suppression, little UR to the target stimulus was apparent during preexposure, and no detectable LTH. Thus, there was no difference between the PE and NPE groups on the first conditioning trial. Whether the UR to the CS confounds the interpretation of LI (Exp. 1) or not (Exp. 2) can only be known if the UR is measured. In both experiments, LI was observed in acquisition. Also in both experiments, rats that were preexposed and then conditioned to asymptote were significantly more resistant to extinction than were the rats not preexposed. This result contrasts with the consistently reported finding that preexposure either produces less resistance to extinction or has no effect on extinction. The effect of stimulus preexposure survived conditioning to asymptote and was reflected directly in extinction. These two experiments provide a cautionary procedural note for LI experiments and have shown an unexpected extinction effect that may provide new insights into the interpretation of LI.

  1. Fear inhibition in high trait anxiety.

    Science.gov (United States)

    Kindt, Merel; Soeter, Marieke

    2014-01-01

    Trait anxiety is recognized as an individual risk factor for the development of anxiety disorders but the neurobiological mechanisms remain unknown. Here we test whether trait anxiety is associated with impaired fear inhibition utilizing the AX+/BX- conditional discrimination procedure that allows for the independent evaluation of startle fear potentiation and inhibition of fear. Sixty undergraduate students participated in the study--High Trait Anxious: n = 28 and Low Trait Anxious: n = 32. We replicated earlier findings that a transfer of conditioned inhibition for startle responses requires contingency awareness. However, contrary to the fear inhibition hypothesis, our data suggest that high trait anxious individuals show a normal fear inhibition of conditioned startle responding. Only at the cognitive level the high trait anxious individuals showed evidence for impaired inhibitory learning of the threat cue. Together with other findings where impaired fear inhibition was only observed in those PTSD patients who were either high on hyperarousal symptoms or with current anxiety symptoms, we question whether impaired fear inhibition is a biomarker for the development of anxiety disorders.

  2. BST2/Tetherin Inhibition of Alphavirus Exit

    Directory of Open Access Journals (Sweden)

    Yaw Shin Ooi

    2015-04-01

    Full Text Available Alphaviruses such as chikungunya virus (CHIKV and Semliki Forest virus (SFV are small enveloped RNA viruses that bud from the plasma membrane. Tetherin/BST2 is an interferon-induced host membrane protein that inhibits the release of many enveloped viruses via direct tethering of budded particles to the cell surface. Alphaviruses have highly organized structures and exclude host membrane proteins from the site of budding, suggesting that their release might be insensitive to tetherin inhibition. Here, we demonstrated that exogenously-expressed tetherin efficiently inhibited the release of SFV and CHIKV particles from host cells without affecting virus entry and infection. Alphavirus release was also inhibited by the endogenous levels of tetherin in HeLa cells. While rubella virus (RuV and dengue virus (DENV have structural similarities to alphaviruses, tetherin inhibited the release of RuV but not DENV. We found that two recently identified tetherin isoforms differing in length at the N-terminus exhibited distinct capabilities in restricting alphavirus release. SFV exit was efficiently inhibited by the long isoform but not the short isoform of tetherin, while both isoforms inhibited vesicular stomatitis virus exit. Thus, in spite of the organized structure of the virus particle, tetherin specifically blocks alphavirus release and shows an interesting isoform requirement.

  3. The IFITMs Inhibit Zika Virus Replication

    Directory of Open Access Journals (Sweden)

    George Savidis

    2016-06-01

    Full Text Available Zika virus has emerged as a severe health threat with a rapidly expanding range. The IFITM family of restriction factors inhibits the replication of a broad range of viruses, including the closely related flaviruses West Nile virus and dengue virus. Here, we show that IFITM1 and IFITM3 inhibit Zika virus infection early in the viral life cycle. Moreover, IFITM3 can prevent Zika-virus-induced cell death. These results suggest that strategies to boost the actions and/or levels of the IFITMs might be useful for inhibiting a broad range of emerging viruses.

  4. Reversible Inhibition of Cellular Metabolism by Ribavirin

    Science.gov (United States)

    Larsson, Alf; Stenberg, Kjell; Öberg, Bo

    1978-01-01

    The broad spectrum antiviral drug ribavirin (Virazole, 1-β-d-ribofuranosyl-1,2,4-triazole-3-carboxamide) inhibits cellular macromolecular synthesis as well as cell division in eucaryotic cells. The concentration and time dependence have been studied. One-hour treatment with 25 μM ribavirin or 18 h with 2 μM inhibited the deoxyribonucleic acid synthesis to 50%. Higher concentrations of ribavirin were required to obtain a similar inhibition of ribonucleic acid and protein synthesis. This effect on cell metabolism and cell division can be reversed by removing the drug from the cells. PMID:646339

  5. Lobelane inhibits methamphetamine-evoked dopamine release via inhibition of the vesicular monoamine transporter-2.

    Science.gov (United States)

    Nickell, Justin R; Krishnamurthy, Sairam; Norrholm, Seth; Deaciuc, Gabriela; Siripurapu, Kiran B; Zheng, Guangrong; Crooks, Peter A; Dwoskin, Linda P

    2010-02-01

    Lobeline is currently being evaluated in clinical trials as a methamphetamine abuse treatment. Lobeline interacts with nicotinic receptor subtypes, dopamine transporters (DATs), and vesicular monoamine transporters (VMAT2s). Methamphetamine inhibits VMAT2 and promotes dopamine (DA) release from synaptic vesicles, resulting ultimately in increased extracellular DA. The present study generated structure-activity relationships by defunctionalizing the lobeline molecule and determining effects on [(3)H]dihydrotetrabenazine binding, inhibition of [(3)H]DA uptake into striatal synaptic vesicles and synaptosomes, the mechanism of VMAT2 inhibition, and inhibition of methamphetamine-evoked DA release. Compared with lobeline, the analogs exhibited greater potency inhibiting DA transporter (DAT) function. Saturated analogs, lobelane and nor-lobelane, exhibited high potency (K(i) = 45 nM) inhibiting vesicular [(3)H]DA uptake, and lobelane competitively inhibited VMAT2 function. Lobeline and lobelane exhibited 67- and 35-fold greater potency, respectively, in inhibiting VMAT2 function compared to DAT function. Lobelane potently decreased (IC(50) = 0.65 microM; I(max) = 73%) methamphetamine-evoked DA overflow, and with a greater maximal effect compared with lobeline (IC(50) = 0.42 microM, I(max) = 56.1%). These results provide support for VMAT2 as a target for inhibition of methamphetamine effects. Both trans-isomers and demethylated analogs of lobelane had reduced or unaltered potency inhibiting VMAT2 function and lower maximal inhibition of methamphetamine-evoked DA release compared with lobelane. Thus, defunctionalization, cis-stereochemistry of the side chains, and presence of the piperidino N-methyl are structural features that afford greatest inhibition of methamphetamine-evoked DA release and enhancement of selectivity for VMAT2. The current results reveal that lobelane, a selective VMAT2 inhibitor, inhibits methamphetamine-evoked DA release and is a promising lead for

  6. Lobelane Inhibits Methamphetamine-Evoked Dopamine Release via Inhibition of the Vesicular Monoamine Transporter-2S⃞

    Science.gov (United States)

    Nickell, Justin R.; Krishnamurthy, Sairam; Norrholm, Seth; Deaciuc, Gabriela; Siripurapu, Kiran B.; Zheng, Guangrong; Crooks, Peter A.

    2010-01-01

    Lobeline is currently being evaluated in clinical trials as a methamphetamine abuse treatment. Lobeline interacts with nicotinic receptor subtypes, dopamine transporters (DATs), and vesicular monoamine transporters (VMAT2s). Methamphetamine inhibits VMAT2 and promotes dopamine (DA) release from synaptic vesicles, resulting ultimately in increased extracellular DA. The present study generated structure-activity relationships by defunctionalizing the lobeline molecule and determining effects on [3H]dihydrotetrabenazine binding, inhibition of [3H]DA uptake into striatal synaptic vesicles and synaptosomes, the mechanism of VMAT2 inhibition, and inhibition of methamphetamine-evoked DA release. Compared with lobeline, the analogs exhibited greater potency inhibiting DA transporter (DAT) function. Saturated analogs, lobelane and nor-lobelane, exhibited high potency (Ki = 45 nM) inhibiting vesicular [3H]DA uptake, and lobelane competitively inhibited VMAT2 function. Lobeline and lobelane exhibited 67- and 35-fold greater potency, respectively, in inhibiting VMAT2 function compared to DAT function. Lobelane potently decreased (IC50 = 0.65 μM; Imax = 73%) methamphetamine-evoked DA overflow, and with a greater maximal effect compared with lobeline (IC50 = 0.42 μM, Imax = 56.1%). These results provide support for VMAT2 as a target for inhibition of methamphetamine effects. Both trans-isomers and demethylated analogs of lobelane had reduced or unaltered potency inhibiting VMAT2 function and lower maximal inhibition of methamphetamine-evoked DA release compared with lobelane. Thus, defunctionalization, cis-stereochemistry of the side chains, and presence of the piperidino N-methyl are structural features that afford greatest inhibition of methamphetamine-evoked DA release and enhancement of selectivity for VMAT2. The current results reveal that lobelane, a selective VMAT2 inhibitor, inhibits methamphetamine-evoked DA release and is a promising lead for the development of a

  7. Inhibition of urinary calculi -- a spectroscopic study

    Science.gov (United States)

    Manciu, Felicia; Govani, Jayesh; Durrer, William; Reza, Layra; Pinales, Luis

    2008-10-01

    Although a considerable number of investigations have already been undertaken and many causes such as life habits, metabolic disorders, and genetic factors have been noted as sources that accelerate calculi depositions and aggregations, there are still plenty of unanswered questions regarding efficient inhibition and treatment mechanisms. Thus, in an attempt to acquire more insights, we propose here a detailed scientific study of kidney stone formation and growth inhibition based on a traditional medicine approach with Rotula Aquatica Lour (RAL) herbal extracts. A simplified single diffusion gel growth technique was used for synthesizing the samples for the present study. The unexpected Zn presence in the sample with RAL inhibitor, as revealed by XPS measurements, explains the inhibition process and the dramatic reflectance of the incident light observed in the infrared transmission studies. Raman data demonstrate potential binding of the inhibitor with the oxygen of the kidney stone. Photoluminescence results corroborate to provide additional evidence of Zn-related inhibition.

  8. Toxicants inhibiting anaerobic digestion: a review.

    Science.gov (United States)

    Chen, Jian Lin; Ortiz, Raphael; Steele, Terry W J; Stuckey, David C

    2014-12-01

    Anaerobic digestion is increasingly being used to treat wastes from many sources because of its manifold advantages over aerobic treatment, e.g. low sludge production and low energy requirements. However, anaerobic digestion is sensitive to toxicants, and a wide range of compounds can inhibit the process and cause upset or failure. Substantial research has been carried out over the years to identify specific inhibitors/toxicants, and their mechanism of toxicity in anaerobic digestion. In this review we present a detailed and critical summary of research on the inhibition of anaerobic processes by specific organic toxicants (e.g., chlorophenols, halogenated aliphatics and long chain fatty acids), inorganic toxicants (e.g., ammonia, sulfide and heavy metals) and in particular, nanomaterials, focusing on the mechanism of their inhibition/toxicity. A better understanding of the fundamental mechanisms behind inhibition/toxicity will enhance the wider application of anaerobic digestion.

  9. Glycerol inhibition of ruminal lipolysis in vitro

    Science.gov (United States)

    Supplemental glycerol inhibits rumen lipolysis, a prerequisite for rumen biohydrogenation, which is responsible for the saturation of dietary fatty acids consumed by ruminant animals. Feeding excess glycerol, however, adversely affects dry matter digestibility. To more clearly define the effect of...

  10. Neomycin inhibits angiogenin-induced angiogenesis

    OpenAIRE

    1998-01-01

    A class of angiogenesis inhibitor has emerged from our mechanistic study of the action of angiogenin, a potent angiogenic factor. Neomycin, an aminoglycoside antibiotic, inhibits nuclear translocation of human angiogenin in human endothelial cells, an essential step for angiogenin-induced angiogenesis. The phospholipase C-inhibiting activity of neomycin appears to be involved, because U-73122, another phospholipase C inhibitor, has a similar effect. In contrast, genistein, oxophenylarsine, an...

  11. Neomycin inhibits angiogenin-induced angiogenesis

    OpenAIRE

    Hu, Guo-fu

    1998-01-01

    A class of angiogenesis inhibitor has emerged from our mechanistic study of the action of angiogenin, a potent angiogenic factor. Neomycin, an aminoglycoside antibiotic, inhibits nuclear translocation of human angiogenin in human endothelial cells, an essential step for angiogenin-induced angiogenesis. The phospholipase C-inhibiting activity of neomycin appears to be involved, because U-73122, another phospholipase C inhibitor, has a similar effect. In contrast, genistein, oxophenylarsine, an...

  12. Inhibited solid propellant composition containing beryllium hydride

    Science.gov (United States)

    Thompson, W. W. (Inventor)

    1978-01-01

    An object of this invention is to provide a composition of beryllium hydride and carboxy-terminated polybutadiene which is stable. Another object of this invention is to provide a method for inhibiting the reactivity of beryllium hydride toward carboxy-terminated polybutadiene. It was found that a small amount of lecithin inhibits the reaction of beryllium hydride with the acid groups in carboxy terminated polybutadiene.

  13. The inhibition of monoamine oxidase by esomeprazole

    OpenAIRE

    2013-01-01

    Virtual screening of a library of drugs has suggested that esomeprazole, the S-enantiomer of omeprazole, may possess binding affinities for the active sites of the monoamine oxidase (MAO) A and B enzymes. Based on this finding, the current study examines the MAO inhibitory properties of esomeprazole. Using recombinant human MAO-A and MAO-B, IC50 values for the inhibition of these enzymes by esomeprazole were experimentally determined. To examine the reversibility of MAO inhibition by esomepra...

  14. Piperine, a dietary phytochemical, inhibits angiogenesis

    OpenAIRE

    2012-01-01

    Angiogenesis plays an important role in tumor progression. Piperine, a major alkaloid constituent of black pepper, has diverse physiological actions including killing of cancer cells; however, the effect of piperine on angiogenesis is not known. Here we show that piperine inhibited the proliferation and G1/S transition of human umbilical vein endothelial cells (HUVECs) without causing cell death. Piperine also inhibited HUVEC migration and tubule formation in vitro, as well as collagen-induce...

  15. Protective effect of indole-3-pyruvate against ultraviolet b-induced damage to cultured HaCaT keratinocytes and the skin of hairless mice.

    Directory of Open Access Journals (Sweden)

    Reiji Aoki

    Full Text Available Previous investigations demonstrated that pyruvate protects human keratinocytes against cell damage stemming from exposure to ultraviolet B (UVB radiation. This study endeavoured to elucidate the protective capacity of aromatic pyruvates (e.g., phenylpyruvate (PPyr, 4-hydroxyphenylpyruvate (HPPyr, and indole-3-pyruvate (IPyr against UVB-induced injury to skin cells, both in vitro and in vivo. Cultured human HaCaT keratinocytes were irradiated with UVB light (60 mJ/cm2 and maintained with or without test compounds (1-25 mM.In addition, the dorsal skin of hairless mice (HR-1 was treated with test compounds (10 μmol and exposed to UVB light (1 J/cm2 twice [corrected]. The ability of the test compounds to ameliorate UVB-induced cytotoxicity and inflammation was then assessed. Aromatic pyruvates reduced cytotoxicity in UVB-irradiated HaCaT keratinocytes, and also diminished the expression of interleukin 1β (IL-1β and interleukin 6 (IL-6. IPyr was more efficacious than either PPyr or HPPyr. Furthermore, only IPyr inhibited cyclooxygenase-2 (Cox-2 expression at both the mRNA and the protein level in UVB-treated keratinocytes. Topical application of IPyr to the dorsal skin of hairless mice reduced the severity of UVB-induced skin lesions, the augmentation of dermal thickness, and transepithelial water loss. Overproduction of IL-1β and IL-6 in response to UVB radiation was also suppressed in vivo by the topical administration of IPyr. These data strongly suggest that IPyr might find utility as a UVB-blocking reagent in therapeutic strategies to lessen UVB-induced inflammatory skin damage.

  16. Anti-Inflammatory Effects of Aspalathus linearis and Cyclopia spp. Extracts in a UVB/Keratinocyte (HaCaT Model Utilising Interleukin-1α Accumulation as Biomarker

    Directory of Open Access Journals (Sweden)

    Tandeka Magcwebeba

    2016-10-01

    Full Text Available Ultraviolet B (UVB radiation is one of the major predisposing risk factors of skin cancer. The anticancer and photoprotective effects of unoxidized rooibos (Aspalathus linearis and honeybush (Cyclopia herbal teas, containing high levels of dihydrochalones and xanthones, respectively, have been demonstrated in skin cancer models in vivo. In the current study, the anti-inflammatory effects of methanol and aqueous extracts of these herbal teas were investigated in a UVB/HaCaT keratinocyte model with intracellular interleukin-1α (icIL-1α accumulation as a biomarker. Extracts of green tea (Camellia sinensis served as benchmark. Both extracts of green tea and rooibos, as well as the aqueous extract of C. intermedia, enhanced UVB-induced inhibition of cell viability, proliferation and induction of apoptosis, facilitating the removal of icIL-1α. The underlying mechanisms may involve mitochondrial dysfunction exhibiting pro-oxidant responses via polyphenol-iron interactions. The methanol extracts of honeybush, however, protected against UVB-induced reduction of cell growth parameters, presumably via antioxidant mechanisms that prevented the removal of highly inflamed icIL-1α-containing keratinocytes via apoptosis. The dual antioxidant and/or pro-oxidant role of the polyphenolic herbal tea constituents should be considered in developing preventive strategies against UVB-induced skin carcinogenesis. The indirect removal of UVB damaged keratinocytes by herbal tea extracts via apoptosis may find application in the prevention of photo-induced inflammation.

  17. Potential for tyndalized Lactobacillus acidophilus as an effective component in moisturizing skin and anti-wrinkle products.

    Science.gov (United States)

    Im, A-Rang; Kim, Hui Seong; Hyun, Jin Won; Chae, Sungwook

    2016-08-01

    It is widely accepted that ultraviolet (UV) irradiation induces skin damage. In the present study, a UVB-induced hairless mouse model of skin photoaging was developed to determine whether tyndalized Lactobacillus acidophilus was able to significantly enhance the repair of photodamaged skin. To evaluate the effects of tyndalized L. acidophilus on UVB-induced skin-wrinkle formation in vivo, HR-1 hairless male mice were exposed to UVB radiation and orally administered tyndalized L. acidophilus. Compared with the control group, the UVB irradiation mice displayed a significant increase in transepidermal water loss and a reduction in skin hydration. In mice with UVB-induced photodamage, the effacement of the fine wrinkles by tyndalized L. acidophilus was correlated with dermal collagen synthesis, accompanied by histological changes. Furthermore, western blotting was performed to investigate the protein expression levels of matrix metalloproteinases (MMPs) and mitogen-activated protein kinase. Notably, orally administered tyndalized L. acidophilus reduced the expression levels of MMP-1 and MMP-9. Based upon the aforementioned results, it was determined that tyndalized L. acidophilus effectively inhibited the wrinkle formation induced by UVB irradiation, and that this may be attributed to the downregulation of MMPs. Therefore, tyndalized L. acidophilus may be considered a potential agent for preventing skin photoaging and wrinkle formation.

  18. Inhibition in the Human Auditory Cortex.

    Directory of Open Access Journals (Sweden)

    Koji Inui

    Full Text Available Despite their indispensable roles in sensory processing, little is known about inhibitory interneurons in humans. Inhibitory postsynaptic potentials cannot be recorded non-invasively, at least in a pure form, in humans. We herein sought to clarify whether prepulse inhibition (PPI in the auditory cortex reflected inhibition via interneurons using magnetoencephalography. An abrupt increase in sound pressure by 10 dB in a continuous sound was used to evoke the test response, and PPI was observed by inserting a weak (5 dB increase for 1 ms prepulse. The time course of the inhibition evaluated by prepulses presented at 10-800 ms before the test stimulus showed at least two temporally distinct inhibitions peaking at approximately 20-60 and 600 ms that presumably reflected IPSPs by fast spiking, parvalbumin-positive cells and somatostatin-positive, Martinotti cells, respectively. In another experiment, we confirmed that the degree of the inhibition depended on the strength of the prepulse, but not on the amplitude of the prepulse-evoked cortical response, indicating that the prepulse-evoked excitatory response and prepulse-evoked inhibition reflected activation in two different pathways. Although many diseases such as schizophrenia may involve deficits in the inhibitory system, we do not have appropriate methods to evaluate them; therefore, the easy and non-invasive method described herein may be clinically useful.

  19. Inhibition of Heme Peroxidases by Melamine

    Directory of Open Access Journals (Sweden)

    Pattaraporn Vanachayangkul

    2012-01-01

    Full Text Available In 2008 melamine-contaminated infant formula and dairy products in China led to over 50,000 hospitalizations of children due to renal injuries. In North America during 2007 and in Asia during 2004, melamine-contaminated pet food products resulted in numerous pet deaths due to renal failure. Animal studies have confirmed the potent renal toxicity of melamine combined with cyanuric acid. We showed previously that the solubility of melamine cyanurate is low at physiologic pH and ionic strength, provoking us to speculate how toxic levels of these compounds could be transported through the circulation without crystallizing until passing into the renal filtrate. We hypothesized that melamine might be sequestered by heme proteins, which could interfere with heme enzyme activity. Four heme peroxidase enzymes were selected for study: horseradish peroxidase (HRP, lactoperoxidase (LPO, and cyclooxygenase-1 and -2 (COX-1 and -2. Melamine exhibited noncompetitive inhibition of HRP (9.5±0.7mM, and LPO showed a mixed model of inhibition (14.5±4.7mM. The inhibition of HRP and LPO was confirmed using a chemiluminescent peroxidase assay. Melamine also exhibited COX-1 inhibition, but inhibition of COX-2 was not detected. Thus, our results demonstrate that melamine inhibits the activity of three heme peroxidases.

  20. Scale Inhibition of Green Inhibitor Polyepoxysuccinic Sodium

    Institute of Scientific and Technical Information of China (English)

    Feng Hui-xia; Wang Yi; Yu Shu-rong; Liang Bao-feng

    2004-01-01

    Polyepoxysuccinic acid (PESA) is the green water treatment agents recognized all over the world[1-3]. It is found that when PESA is used alone, it had good scale inhibition. PESA should be included in the category of green scale inhibitor.PESA is synthesized with maleicanhydride in the presence of catalysts. The effect on scale-in-hibiting property of the product from amount and feed times of catalyst, the reaction temperature, the reaction time were investigated. The optimum reaction conditions are as follows:n(maleic anhydride):n(Ca(OH)2):n(NaOH)=1:0.05-0.2:0.5, reaction temperature 95C, reaction time 4h.In all the references about PESA, PESA is researched as a kind of highly effective scale inhibitor or chelate. In this paper, the performance of scale inhibition of PESA is evaluated by scale static inhibitor.The results are shown in Figture1.It is evident from our experimental data (Figture1) that when inhibition for CaCO3.With the increase of PESA dosage, scale inhibition increases. When dosage is more than 6mg/L, inhibition efficiency is over 50%. The formulas give scale inhibition efficiency more than 95% at 12mg/L of total dosage.

  1. Spatially reciprocal inhibition of inhibition within a stimulus selection network in the avian midbrain.

    Science.gov (United States)

    Goddard, C Alex; Mysore, Shreesh P; Bryant, Astra S; Huguenard, John R; Knudsen, Eric I

    2014-01-01

    Reciprocal inhibition between inhibitory projection neurons has been proposed as the most efficient circuit motif to achieve the flexible selection of one stimulus among competing alternatives. However, whether such a motif exists in networks that mediate selection is unclear. Here, we study the connectivity within the nucleus isthmi pars magnocellularis (Imc), a GABAergic nucleus that mediates competitive selection in the midbrain stimulus selection network. Using laser photostimulation of caged glutamate, we find that feedback inhibitory connectivity is global within the Imc. Unlike typical lateral inhibition in other circuits, intra-Imc inhibition remains functionally powerful over long distances. Anatomically, we observed long-range axonal projections and retrograde somatic labeling from focal injections of bi-directional tracers in the Imc, consistent with spatial reciprocity of intra-Imc inhibition. Together, the data indicate that spatially reciprocal inhibition of inhibition occurs throughout the Imc. Thus, the midbrain selection circuit possesses the most efficient circuit motif possible for fast, reliable, and flexible selection.

  2. Protective effect of pomegranate-derived products on UVB-mediated damage in human reconstituted skin.

    Science.gov (United States)

    Afaq, Farrukh; Zaid, Mohammad Abu; Khan, Naghma; Dreher, Mark; Mukhtar, Hasan

    2009-06-01

    Solar ultraviolet (UV) radiation, particularly its UVB (290-320 nm) component, is the primary cause of many adverse biological effects including photoageing and skin cancer. UVB radiation causes DNA damage, protein oxidation and induces matrix metalloproteinases (MMPs). Photochemoprevention via the use of botanical antioxidants in affording protection to human skin against UVB damage is receiving increasing attention. Pomegranate, from the tree Punica granatum, contains anthocyanins and hydrolysable tannins and possesses strong antioxidant and anti-tumor-promoting properties. In this study, we determined the effect of pomegranate-derived products--POMx juice, POMx extract and pomegranate oil (POMo)--against UVB-mediated damage using reconstituted human skin (EpiDerm(TM) FT-200). EpiDerm was treated with POMx juice (1-2 microl/0.1 ml/well), POMx extract (5-10 microg/0.1 ml/well) and POMo (1-2 microl/0.1 ml/well) for 1 h prior to UVB (60 mJ/cm(2)) irradiation and was harvested 12 h post-UVB to assess protein oxidation, markers of DNA damage and photoageing by Western blot analysis and immunohistochemistry. Pretreatment of Epiderm with pomegranate-derived products resulted in inhibition of UVB-induced (i) cyclobutane pyrimidine dimers (CPD), (ii) 8-dihydro-2'-deoxyguanosine (8-OHdG), (iii) protein oxidation and (iv) proliferating cell nuclear antigen (PCNA) protein expression. We also found that pretreatment of Epiderm with pomegranate-derived products resulted in inhibition of UVB-induced (i) collagenase (MMP-1), (ii) gelatinase (MMP-2, MMP-9), (iii) stromelysin (MMP-3), (iv) marilysin (MMP-7), (v) elastase (MMP-12) and (vi) tropoelastin. Gelatin zymography revealed that pomegranate-derived products inhibited UVB-induced MMP-2 and MMP-9 activities. Pomegranate-derived products also caused a decrease in UVB-induced protein expression of c-Fos and phosphorylation of c-Jun. Collectively, these results suggest that all three pomegranate-derived products may be useful

  3. Neomycin inhibits angiogenin-induced angiogenesis.

    Science.gov (United States)

    Hu, G F

    1998-08-18

    A class of angiogenesis inhibitor has emerged from our mechanistic study of the action of angiogenin, a potent angiogenic factor. Neomycin, an aminoglycoside antibiotic, inhibits nuclear translocation of human angiogenin in human endothelial cells, an essential step for angiogenin-induced angiogenesis. The phospholipase C-inhibiting activity of neomycin appears to be involved, because U-73122, another phospholipase C inhibitor, has a similar effect. In contrast, genistein, oxophenylarsine, and staurosporine, inhibitors of tyrosine kinase, phosphotyrosine phosphatase, and protein kinase C, respectively, do not inhibit nuclear translocation of angiogenin. Neomycin inhibits angiogenin-induced proliferation of human endothelial cells in a dose-dependent manner. At 50 microM, neomycin abolishes angiogenin-induced proliferation but does not affect the basal level of proliferation and cell viability. Other aminoglycoside antibiotics, including gentamicin, streptomycin, kanamycin, amikacin, and paromomycin, have no effect on angiogenin-induced cell proliferation. Most importantly, neomycin completely inhibits angiogenin-induced angiogenesis in the chicken chorioallantoic membrane at a dose as low as 20 ng per egg. These results suggest that neomycin and its analogs are a class of agents that may be developed for anti-angiogenin therapy.

  4. Aspartate inhibits Staphylococcus aureus biofilm formation.

    Science.gov (United States)

    Yang, Hang; Wang, Mengyue; Yu, Junping; Wei, Hongping

    2015-04-01

    Biofilm formation renders Staphylococcus aureus highly resistant to conventional antibiotics and host defenses. Four D-amino acids (D-Leu, D-Met, D-Trp and D-Tyr) have been reported to be able to inhibit biofilm formation and disassemble established S. aureus biofilms. We report here for the first time that both D- and L-isoforms of aspartate (Asp) inhibited S. aureus biofilm formation on tissue culture plates. Similar biofilm inhibition effects were also observed against other staphylococcal strains, including S. saprophyticus, S. equorum, S. chromogenes and S. haemolyticus. It was found that Asp at high concentrations (>10 mM) inhibited the growth of planktonic N315 cells, but at subinhibitory concentrations decreased the cellular metabolic activity without influencing cell growth. The decreased cellular metabolic activity might be the reason for the production of less protein and DNA in the matrix of the biofilms formed in the presence of Asp. However, varied inhibition efficacies of Asp were observed for biofilms formed by clinical staphylococcal isolates. There might be mechanisms other than decreasing the metabolic activity, e.g. the biofilm phenotypes, affecting biofilm formation in the presence of Asp.

  5. Matrix metalloproteinase inhibition in atherosclerosis and stroke.

    Science.gov (United States)

    Roycik, M D; Myers, J S; Newcomer, R G; Sang, Q-X A

    2013-09-01

    Matrix metalloproteinases (MMPs) are a family of tightly regulated, zinc-dependent proteases that degrade extracellular matrix (ECM), cell surface, and intracellular proteins. Vascular remodeling, whether as a function of normal physiology or as a consequence of a myriad of pathological processes, requires degradation of the ECM. Thus, the expression and activity of many MMPs are up-regulated in numerous conditions affecting the vasculature and often exacerbate vascular dysfunction. A growing body of evidence supports the rationale of using MMP inhibitors for the treatment of cardiovascular diseases, stroke, and chronic vascular dementia. This manuscript will examine promising targets for MMP inhibition in atherosclerosis and stroke, reviewing findings in preclinical animal models and human patient studies. Strategies for MMP inhibition have progressed beyond chelating the catalytic zinc to functional blocking antibodies and peptides that target either the active site or exosites of the enzyme. While the inhibition of MMP activity presents a rational therapeutic avenue, the multiplicity of roles for MMPs and the non-selective nature of MMP inhibitors that cause unintended side-effects hinder full realization of MMP inhibition as therapy for vascular disease. For optimal therapeutic effects to be realized, specific targets for MMP inhibition in these pathologies must first be identified and then attacked by potent and selective agents during the most appropriate timepoint.

  6. Genistein inhibits differentiation of primary human adipocytes.

    Science.gov (United States)

    Park, Hea Jin; Della-Fera, Mary Anne; Hausman, Dorothy B; Rayalam, Srujana; Ambati, Suresh; Baile, Clifton A

    2009-02-01

    Genistein, a major soy isoflavone, has been reported to exhibit antiadipogenic and proapoptotic potential in vivo and in vitro. It is also a phytoestrogen which has high affinity to estrogen receptor beta. In this study, we determined the effect of genistein on adipogenesis and estrogen receptor (ER) alpha and beta expression during differentiation in primary human preadipocytes. Genistein inhibited lipid accumulation in a dose-dependent manner at concentrations of 6.25 microM and higher, with 50 microM genistein inhibiting lipid accumulation almost completely. Low concentrations of genistein (3.25 microM) increased cell viability and higher concentrations (25 and 50 microM) decreased it by 16.48+/-1.35% (P<.0001) and 50.68+/-1.34% (P<.0001). Oil Red O staining was used to confirm the effects on lipid accumulation. The inhibition of lipid accumulation was associated with inhibition of glycerol-3-phosphate dehydrogenase activity and down-regulation of expression of adipocyte-specific genes, including peroxisome proliferator-activated receptor gamma, CCAAT/enhancer binding protein alpha, glycerol-3-phosphate dehydrogenase, adipocyte fatty acid binding protein, fatty acid synthase, sterol regulatory element-binding protein 1, perilipin, leptin, lipoprotein lipase and hormone-sensitive lipase. These effects of genistein during the differentiation period were associated with down-regulation of ERalpha and ERbeta expression. This study adds to the elucidation of the molecular pathways involved in the inhibition of adipogenesis by phytoestrogens.

  7. Inhibition of ethylene production by putrescine alleviates aluminium-induced root inhibition in wheat plants.

    Science.gov (United States)

    Yu, Yan; Jin, Chongwei; Sun, Chengliang; Wang, Jinghong; Ye, Yiquan; Zhou, Weiwei; Lu, Lingli; Lin, Xianyong

    2016-01-08

    Inhibition of root elongation is one of the most distinct symptoms of aluminium (Al) toxicity. Although putrescine (Put) has been identified as an important signaling molecule involved in Al tolerance, it is yet unknown how Put mitigates Al-induced root inhibition. Here, the possible mechanism was investigated by using two wheat genotypes differing in Al resistance: Al-tolerant Xi Aimai-1 and Al-sensitive Yangmai-5. Aluminium caused more root inhibition in Yangmai-5 and increased ethylene production at the root apices compared to Xi Aimai-1, whereas the effects were significantly reversed by ethylene biosynthesis inhibitors. The simultaneous exposure of wheat seedlings to Al and ethylene donor, ethephon, or ethylene biosynthesis precursor, 1-aminocyclopropane-1-carboxylic acid (ACC), increased ethylene production and aggravated root inhibition, which was more pronounced in Xi Aimai-1. In contrast, Put treatment decreased ethylene production and alleviated Al-induced root inhibition in both genotypes, and the effects were more conspicuous in Yangmai-5. Furthermore, our results indicated that Al-induced ethylene production was mediated by ACC synthase (ACS) and ACC oxidase, and that Put decreased ethylene production by inhibiting ACS. Altogether, these findings indicate that ethylene is involved in Al-induced root inhibition and this process could be alleviated by Put through inhibiting ACS activity.

  8. The role of (dis)inhibition in creativity: decreased inhibition improves idea generation.

    Science.gov (United States)

    Radel, Rémi; Davranche, Karen; Fournier, Marion; Dietrich, Arne

    2015-01-01

    There is now a large body of evidence showing that many different conditions related to impaired fronto-executive functioning are associated with the enhancement of some types of creativity. In this paper, we pursue the possibility that the central mechanism associated with this effect might be a reduced capacity to exert inhibition. We tested this hypothesis by exhausting the inhibition efficiency through prolonged and intensive practice of either the Simon or the Eriksen Flanker task. Performance on another inhibition task indicated that only the cognitive resources for inhibition of participants facing high inhibition demands were impaired. Subsequent creativity tests revealed that exposure to high inhibition demands led to enhanced fluency in a divergent thinking task (Alternate Uses Task), but no such changes occurred in a convergent task (Remote Associate Task; studies 1a and 1b). The same manipulation also led to a hyper-priming effect for weakly related primes in a Lexical Decision Task (Study 2). Together, these findings suggest that inhibition selectively affects some types of creative processes and that, when resources for inhibition are lacking, the frequency and the originality of ideas was facilitated.

  9. Structural basis for transcription inhibition by tagetitoxin.

    Science.gov (United States)

    Vassylyev, Dmitry G; Svetlov, Vladimir; Vassylyeva, Marina N; Perederina, Anna; Igarashi, Noriyuki; Matsugaki, Naohiro; Wakatsuki, Soichi; Artsimovitch, Irina

    2005-12-01

    Tagetitoxin (Tgt) inhibits transcription by an unknown mechanism. A structure at a resolution of 2.4 A of the Thermus thermophilus RNA polymerase (RNAP)-Tgt complex revealed that the Tgt-binding site within the RNAP secondary channel overlaps that of the stringent control effector ppGpp, which partially protects RNAP from Tgt inhibition. Tgt binding is mediated exclusively through polar interactions with the beta and beta' residues whose substitutions confer resistance to Tgt in vitro. Importantly, a Tgt phosphate, together with two active site acidic residues, coordinates the third Mg(2+) ion, which is distinct from the two catalytic metal ions. We show that Tgt inhibits all RNAP catalytic reactions and propose a mechanism in which the Tgt-bound Mg(2+) ion has a key role in stabilization of an inactive transcription intermediate. Remodeling of the active site by metal ions could be a common theme in the regulation of catalysis by nucleic acid enzymes.

  10. Mapuche herbal medicine inhibits blood platelet aggregation.

    Science.gov (United States)

    Falkenberg, Susan Skanderup; Tarnow, Inge; Guzman, Alfonso; Mølgaard, Per; Simonsen, Henrik Toft

    2012-01-01

    12 plant species traditionally used by the Mapuche people in Chile to treat wounds and inflammations have been evaluated for their direct blood platelet inhibition. Seven of the 12 tested plant species showed platelet inhibitory effect in sheep blood, and four of these were also able to inhibit the ADP- (5.0 μM) and collagen- (2.0 μg/mL) induced aggregations in human blood. These four species in respective extracts (in brackets) were Blechnum chilense (MeOH), Luma apiculata (H(2)O), Amomyrtus luma (DCM : MeOH 1 : 1) and Cestrum parqui (DCM : MeOH 1 : 1). The platelet aggregating inhibitory effects of A. luma (DCM : MeOH 1 : 1), and L. apiculata (H(2)O) were substantial and confirmed by inhibition of platelet surface activation markers.

  11. Anticancer Alkaloid Lamellarins Inhibit Protein Kinases

    Directory of Open Access Journals (Sweden)

    Laurent Meijer

    2008-10-01

    Full Text Available Lamellarins, a family of hexacyclic pyrrole alkaloids originally isolated from marine invertebrates, display promising anti-tumor activity. They induce apoptotic cell death through multi-target mechanisms, including inhibition of topoisomerase I, interaction with DNA and direct effects on mitochondria. We here report that lamellarins inhibit several protein kinases relevant to cancer such as cyclin-dependent kinases, dualspecificity tyrosine phosphorylation activated kinase 1A, casein kinase 1, glycogen synthase kinase-3 and PIM-1. A good correlation is observed between the effects of lamellarins on protein kinases and their action on cell death, suggesting that inhibition of specific kinases may contribute to the cytotoxicity of lamellarins. Structure/activity relationship suggests several paths for the optimization of lamellarins as kinase inhibitors.

  12. Mapuche Herbal Medicine Inhibits Blood Platelet Aggregation

    Directory of Open Access Journals (Sweden)

    Susan Skanderup Falkenberg

    2012-01-01

    Full Text Available 12 plant species traditionally used by the Mapuche people in Chile to treat wounds and inflammations have been evaluated for their direct blood platelet inhibition. Seven of the 12 tested plant species showed platelet inhibitory effect in sheep blood, and four of these were also able to inhibit the ADP- (5.0 μM and collagen- (2.0 μg/mL induced aggregations in human blood. These four species in respective extracts (in brackets were Blechnum chilense (MeOH, Luma apiculata (H2O, Amomyrtus luma (DCM : MeOH 1 : 1 and Cestrum parqui (DCM : MeOH 1 : 1. The platelet aggregating inhibitory effects of A. luma (DCM : MeOH 1 : 1, and L. apiculata (H2O were substantial and confirmed by inhibition of platelet surface activation markers.

  13. Complete corrosion inhibition through graphene defect passivation.

    Science.gov (United States)

    Hsieh, Ya-Ping; Hofmann, Mario; Chang, Kai-Wen; Jhu, Jian Gang; Li, Yuan-Yao; Chen, Kuang Yao; Yang, Chang Chung; Chang, Wen-Sheng; Chen, Li-Chyong

    2014-01-28

    Graphene is expected to enable superior corrosion protection due to its impermeability and chemical inertness. Previous reports, however, demonstrate limited corrosion inhibition and even corrosion enhancement of graphene on metal surfaces. To enable the reliable and complete passivation, the origin of the low inhibition efficiency of graphene was investigated. Combining electrochemical and morphological characterization techniques, nanometer-sized structural defects in chemical vapor deposition grown graphene were found to be the cause for the limited passivation effect. Extremely fast mass transport on the order of meters per second both across and parallel to graphene layers results in an inhibition efficiency of only ∼50% for Cu covered with up to three graphene layers. Through selective passivation of the defects by atomic layer deposition (ALD) an enhanced corrosion protection of more than 99% was achieved, which compares favorably with commercial corrosion protection methods.

  14. Mesoporous silica nanoparticles inhibit cellular respiration.

    Science.gov (United States)

    Tao, Zhimin; Morrow, Matthew P; Asefa, Tewodros; Sharma, Krishna K; Duncan, Cole; Anan, Abhishek; Penefsky, Harvey S; Goodisman, Jerry; Souid, Abdul-Kader

    2008-05-01

    We studied the effect of two types of mesoporous silica nanoparticles, MCM-41 and SBA-15, on mitochondrial O 2 consumption (respiration) in HL-60 (myeloid) cells, Jurkat (lymphoid) cells, and isolated mitochondria. SBA-15 inhibited cellular respiration at 25-500 microg/mL; the inhibition was concentration-dependent and time-dependent. The cellular ATP profile paralleled that of respiration. MCM-41 had no noticeable effect on respiration rate. In cells depleted of metabolic fuels, 50 microg/mL SBA-15 delayed the onset of glucose-supported respiration by 12 min and 200 microg/mL SBA-15 by 34 min; MCM-41 also delayed the onset of glucose-supported respiration. Neither SBA-15 nor MCM-41 affected cellular glutathione. Both nanoparticles inhibited respiration of isolated mitochondria and submitochondrial particles.

  15. Quantifying hydrate formation and kinetic inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Sloan, E.D.; Subramanian, S.; Matthews, P.N.; Lederhos, J.P.; Khokhar, A.A. [Colorado School of Mines, Golden, CO (United States). Center for Hydrate Research

    1998-08-01

    In the Prausnitz tradition, molecular and macroscopic evidence of hydrate formation and kinetic inhibition is presented. On the microscopic level, the first Raman spectra are presented for the formation of both uninhibited and inhibited methane hydrates with time. This method has the potential to provide a microscopic-based kinetics model. Three macroscopic aspects of natural gas hydrate kinetic inhibition are also reported: (1) The effect of hydrate dissociation residual structures was measured, which has application in decreasing the time required for subsequent formation. (2) The performance of a kinetic inhibitor (poly(N-vinylcaprolactam) or PVCap) was measured and correlated as a function of PVCap molecular weight and concentrations of PVCap, methanol, and salt in the aqueous phase. (3) Long-duration test results indicated that the use of PVCap can prevent pipeline blockage for a time exceeding the aqueous phase residence time in some gas pipelines.

  16. Inhibition of aluminum corrosion using Opuntia extract

    Energy Technology Data Exchange (ETDEWEB)

    El-Etre, A.Y

    2003-11-01

    The inhibitive action of the mucilage extracted from the modified stems of prickly pears, toward acid corrosion of aluminum, is tested using weight loss, thermometry, hydrogen evolution and polarization techniques. It was found that the extract acts as a good corrosion inhibitor for aluminum corrosion in 2.0 M HCl solution. The inhibition action of the extract was discussed in view of Langmuir adsorption isotherm. It was found that the adsorption of the extract on aluminum surface is a spontaneous process. The inhibition efficiency (IE) increases as the extract concentration is increased. The effect of temperature on the IE was studied. It was found that the presence of extract increases the activation energy of the corrosion reaction. Moreover, the thermodynamic parameters of the adsorption process were calculated. It was found also that the Opuntia extract provides a good protection to aluminum against pitting corrosion in chloride ion containing solutions.

  17. Silver-Palladium Surfaces Inhibit Biofilm Formation

    DEFF Research Database (Denmark)

    Chiang, Wen-Chi; Schroll, Casper; Hilbert, Lisbeth Rischel

    2009-01-01

    Undesired biofilm formation is a major concern in many areas. In the present study, we investigated biofilm-inhibiting properties of a silver-palladium surface that kills bacteria by generating microelectric fields and electrochemical redox processes. For evaluation of the biofilm inhibition...... efficacy and study of the biofilm inhibition mechanism, the silver-sensitive Escherichia coli J53 and the silver-resistant E. coli J53[pMG101] strains were used as model organisms, and batch and flow chamber setups were used as model systems. In the case of the silver-sensitive strain, the silver......-palladium surfaces killed the bacteria and prevented biofilm formation under conditions of low or high bacterial load. In the case of the silver-resistant strain, the silver-palladium surfaces killed surface-associated bacteria and prevented biofilm formation under conditions of low bacterial load, whereas under...

  18. Neural inhibition enables selection during language processing.

    Science.gov (United States)

    Snyder, Hannah R; Hutchison, Natalie; Nyhus, Erika; Curran, Tim; Banich, Marie T; O'Reilly, Randall C; Munakata, Yuko

    2010-09-21

    Whether grocery shopping or choosing words to express a thought, selecting between options can be challenging, especially for people with anxiety. We investigate the neural mechanisms supporting selection during language processing and its breakdown in anxiety. Our neural network simulations demonstrate a critical role for competitive, inhibitory dynamics supported by GABAergic interneurons. As predicted by our model, we find that anxiety (associated with reduced neural inhibition) impairs selection among options and associated prefrontal cortical activity, even in a simple, nonaffective verb-generation task, and the GABA agonist midazolam (which increases neural inhibition) improves selection, whereas retrieval from semantic memory is unaffected when selection demands are low. Neural inhibition is key to choosing our words.

  19. Pyrilamine inhibits nicotine-induced catecholamine secretion.

    Science.gov (United States)

    Kim, Dong-Chan; Yun, So Jeong; Park, Yong-Soo; Jun, Dong-Jae; Kim, Dongjin; Jiten Singh, N; Kim, Sanguk; Kim, Kyong-Tai

    2014-07-01

    Function of nicotine, which induces activation of all parts of the body including our brain, has been receiving much attention for a long period of time and also been actively studied by researchers for its pharmacological actions in the central nervous system. The modulation of nicotine concentration and the inhibition of nicotine binding on target receptors in the brain are the key factors for smoking addiction therapy. In previous studies showed that influx of nicotine at the blood-brain barrier was through the pyrilamine-sensitive organic cation transporters. But the direct interacting mechanism of pyrilamine on the nicotine binding target receptors has not yet been clarified. The aim of the present study is to investigate the direct binding mechanisms of a pyrilamine on the nicotinic acetylcholine receptors (nAChRs). We found that pyrilamine shares the same ligand binding pocket of nicotine (NCT) on nAChRs but interacts with more amino acid residues than NCT does. The extended part of pyrilamine interacts with additional residues in the ligand binding pocket of nAChRs which are located nearby the entrance of the binding pocket. The catecholamine (CA) secretion induced by nAChR agonist (NCT') was significantly inhibited by the pyrilamine pretreatment. Real time carbon-fiber amperometry confirmed the inhibition of the NCT'-induced exocytosis by pyrilamine in a single cell level. We also found that pyrilamine inhibited the NCT'-induced [Ca(2+)]i. In contrast, pyrilamine did not affect the increase in calcium induced by high K(+). Overall, these data suggest that pyrilamine directly docks into the ligand binding site of nAChRs and specifically inhibits the nAChR-mediated effects thereby causing inhibition of CA secretion. Therefore, pyrilamine may play an important role to explore new treatments to aid smoking cessation.

  20. Peptide inhibition of human cytomegalovirus infection

    Directory of Open Access Journals (Sweden)

    Morris Cindy A

    2011-02-01

    Full Text Available Abstract Background Human cytomegalovirus (HCMV is the most prevalent congenital viral infection in the United States and Europe causing significant morbidity and mortality to both mother and child. HCMV is also an opportunistic pathogen in immunocompromised individuals, including human immunodeficiency virus (HIV- infected patients with AIDS, and solid organ and allogeneic stem cell transplantation recipients. Current treatments for HCMV-associated diseases are insufficient due to the emergence of drug-induced resistance and cytotoxicity, necessitating novel approaches to limit HCMV infection. The aim of this study was to develop therapeutic peptides targeting glycoprotein B (gB, a major glycoprotein of HCMV that is highly conserved across the Herpesviridae family, that specifically inhibit fusion of the viral envelope with the host cell membrane preventing HCMV entry and infection. Results Using the Wimley-White Interfacial Hydrophobicity Scale (WWIHS, several regions within gB were identified that display a high potential to interact with lipid bilayers of cell membranes and hydrophobic surfaces within proteins. The ability of synthetic peptides analogous to WWIHS-positive sequences of HCMV gB to inhibit viral infectivity was evaluated. Human foreskin fibroblasts (HFF were infected with the Towne-GFP strain of HCMV (0.5 MOI, preincubated with peptides at a range of concentrations (78 nm to 100 μM, and GFP-positive cells were visualized 48 hours post-infection by fluorescence microscopy and analyzed quantitatively by flow cytometry. Peptides that inhibited HCMV infection demonstrated different inhibitory concentration curves indicating that each peptide possesses distinct biophysical properties. Peptide 174-200 showed 80% inhibition of viral infection at a concentration of 100 μM, and 51% and 62% inhibition at concentrations of 5 μM and 2.5 μM, respectively. Peptide 233-263 inhibited infection by 97% and 92% at concentrations of 100

  1. Many Putative Endocrine Disruptors Inhibit Prostaglandin Synthesis

    DEFF Research Database (Denmark)

    Kristensen, David M.; Skalkam, Maria L.; Audouze, Karine Marie Laure

    2011-01-01

    Background: Prostaglandins (PGs) play key roles in development and maintenance of homeostasis of the adult body. Despite these important roles, it remains unclear whether the PG pathway is a target for endocrine disruption. However, several known endocrine disrupting compounds (EDCs) share a high...... of endocrine disruption. Results: We found that many known EDCs inhibit the PG pathway in a mouse Sertoli cell line and in human primary mast cells. The EDCs also reduced PG synthesis in ex vivo rat testis and it was correlated with a reduced testosterone production. The inhibition of PG synthesis occurs...

  2. Inhibition of spinach bolting by growth regulators

    Directory of Open Access Journals (Sweden)

    Jan Borkowski

    2015-06-01

    Full Text Available Spinach (Spinacia oleracea L. plants must be harvested during a short period of time because they bolt just after producing some edible leaves. Maleic hydrazide (MH and its commercial preparation "Antyrost" were found to inhibit bolting very strongly. The preparation Off-shoot-O showed very weak activity in suppressing bolting but diminished markedly the resistance of spinach plants to fungus diseases. Triiodobenzoic acid stimulated bolting, and the retardant succinic acid-2-2-dimethylhydrazide (SADH did not affect bolting. Application of MH to inhibit spinach bolting cannot be recommended in practice before investigating the residues of this compound in leaves.

  3. Phytic Acid Inhibits Lipid Peroxidation In Vitro

    OpenAIRE

    Alicja Zajdel; Adam Wilczok; Ludmiła Węglarz; Zofia Dzierżewicz

    2013-01-01

    Phytic acid (PA) has been recognized as a potent antioxidant and inhibitor of iron-catalyzed hydroxyl radical formation under in vitro and in vivo conditions. Therefore, the aim of the present study was to investigate, with the use of HPLC/MS/MS, whether PA is capable of inhibiting linoleic acid autoxidation and Fe(II)/ascorbate-induced peroxidation, as well as Fe(II)/ascorbate-induced lipid peroxidation in human colonic epithelial cells. PA at 100 μM and 500 μM effectively inhibited the deca...

  4. Cerebellar cortical inhibition and classical eyeblink conditioning.

    Science.gov (United States)

    Bao, Shaowen; Chen, Lu; Kim, Jeansok J; Thompson, Richard F

    2002-02-01

    The cerebellum is considered a brain structure in which memories for learned motor responses (e.g., conditioned eyeblink responses) are stored. Within the cerebellum, however, the relative importance of the cortex and the deep nuclei in motor learning/memory is not entirely clear. In this study, we show that the cerebellar cortex exerts both basal and stimulus-activated inhibition to the deep nuclei. Sequential application of a gamma-aminobutyric acid type A receptor (GABA(A)R) agonist and a noncompetitive GABA(A)R antagonist allows selective blockade of stimulus-activated inhibition. By using the same sequential agonist and antagonist methods in behaving animals, we demonstrate that the conditioned response (CR) expression and timing are completely dissociable and involve different inhibitory inputs; although the basal inhibition modulates CR expression, the conditioned stimulus-activated inhibition is required for the proper timing of the CR. In addition, complete blockade of cerebellar deep nuclear GABA(A)Rs prevents CR acquisition. Together, these results suggest that different aspects of the memories for eyeblink CRs are encoded in the cerebellar cortex and the cerebellar deep nuclei.

  5. Hawthorn extract inhibits human isolated neutrophil functions.

    Science.gov (United States)

    Dalli, Ernesto; Milara, Javier; Cortijo, Julio; Morcillo, Esteban J; Cosín-Sales, Juan; Sotillo, José Francisco

    2008-06-01

    Hawthorn extract is a popular herbal medicine given as adjunctive treatment for chronic heart failure. In contrast to the cardiac properties of hawthorn extract, its anti-inflammatory effect has been scarcely investigated. This study examines the effects of a dry extract of leaves and flowers of Crataegus laevigata on various functional outputs of human neutrophils in vitro. Incubation of human neutrophils obtained from peripheral blood of healthy donors with C. laevigata extract (0.75-250 microg/ml) inhibited N-formyl-Met-Leu-Phe (FMLP)-induced superoxide anion generation, elastase release and chemotactic migration with potency values of 43.6, 21.9, and 31.6 microg/ml, respectively. By contrast, serum-opsonized zymosan-induced phagocytosis was unaltered by plant extract. C. laevigata extract (125 microg/ml) reduced FMLP-induced leukotriene B(4) production and lipopolysaccharide-induced generation of tumour necrosis factor-alpha and interleukin-8. Extract inhibited FMLP-induced intracellular calcium signal with potency of 17.4 microg/ml. Extract also markedly inhibited the extracellular calcium entry into calcium-depleted neutrophils, and the thapsigargin-induced intracellular calcium response. In conclusion, C. laevigata extract inhibited various functional outputs of activated human neutrophils which may be relevant to the pathophysiology of cardiac failure.

  6. Stress kinase inhibition modulates acute experimental pancreatitis

    Institute of Scientific and Technical Information of China (English)

    F. Fleischer; R. Dabew; B. Goke; ACC Wagner

    2001-01-01

    AIM To examine the role of p38 during acute experimental cerulein pancreatitis.METHODS Rats were treated with cerulein with or without a specific JNK inhibitor (CEP1347)andy or a specific p38 inhbitor (SB203380) and pancreatic stress kinase activity wasdetermined. Parameters to assess pancreatitis included trypsin, amylase, lipase, pancreatic weight and histology.RESULTS JNK inhibition with CEP1347ameliorated pancreatitis, reducing pancreatic edema. In contrast, p38 inhibition with SB203580aggravated pancreatitis with higher trypsinlevels and, with induction of acinar necrosis not normally found after cerulein hyperstimulation.Simultaneous treatment with both CEP1347 and SB203580 mutually abolished the effects of either compound on cerulein pancreatitis.CONCLUSION Stress kinases modulatepancreatitis differentially. JNK seems to promote pancreatitis development, possibly by supporting inflammatory reactions such as edema formation while its inhibition ameliorates pancreatitis. In contrast, p38 may help reduce organ destruction while inhibition of p38 during induction of cerulein pancreatitis leads to the occurrence of acinar necrosis.

  7. Inhibition of denitrification by ultraviolet radiation

    Science.gov (United States)

    Mancinelli, R. L.; White, M. R.

    It has been shown that UV-A (λ = 320- 400 nm) and UV-B (λ = 280 - 320 nm) inhibit photosynthesis, nitrogen fixation and nitrification. The purpose of this study was to determine the effects, if any, on denitrification in a microbial community inhabiting the intertidal. The community studied is the microbial mat consisting primarily of Lyngbya that inhabits the Pacific marine intertidal, Baja California, Mexico. Rates of denitrification were determined using the acetylene blockage technique. Pseudomonas fluorescens (ATCC # 17400) was used as a control organism, and treated similarly to the mat samples. Samples were incubated either beneath a PAR transparent, UV opaque screen (OP3), or a mylar screen to block UV-B, or a UV transparent screen (UVT) for 2 to 3 hours. Sets of samples were also treated with nitrapyrin to inhibit nitrification, or DCMU to inhibit photosynthesis and treated similarly. Denitrification rates were greater in the UV protected samples than in the UV exposed samples the mat samples as well as for the Ps. fluorescens cultures. Killed controls exhibited no activity. In the DCMU and nitrapyrin treated samples denitrification rates were the same as in the untreated samples. These data indicate that denitrification is directly inhibited by UV radiation.

  8. Acidosis inhibits mineralization in human osteoblasts.

    Science.gov (United States)

    Takeuchi, Shoko; Hirukawa, Koji; Togari, Akifumi

    2013-09-01

    Osteoblasts and osteoclasts maintain bone volume. Acidosis affects the function of these cells including mineral metabolism. We examined the effect of acidosis on the expression of transcription factors and mineralization in human osteoblasts in vitro. Human osteoblasts (SaM-1 cells) derived from the ulnar periosteum were cultured with α-MEM containing 50 μg/ml ascorbic acid and 5 mM β-glycerophosphate (calcifying medium). Acidosis was induced by incubating the SaM-1 cells in 10 % CO₂ (pH approximately 7.0). Mineralization, which was augmented by the calcifying medium, was completely inhibited by acidosis. Acidosis depressed c-Jun mRNA and increased osteoprotegerin (OPG) production in a time-dependent manner. Depressing c-Jun mRNA expression using siRNA increased OPG production and inhibited mineralization. In addition, depressing OPG mRNA expression with siRNA enhanced mineralization in a dose-dependent manner. Acidosis or the OPG protein strongly inhibited mineralization in osteoblasts from neonatal mice. The present study was the first to demonstrate that acidosis inhibited mineralization, depressed c-Jun mRNA expression, and induced OPG production in human osteoblasts. These results suggest that OPG is involved in mineralization via c-Jun in human osteoblasts.

  9. Temporal Preparation, Response Inhibition and Impulsivity

    Science.gov (United States)

    Correa, Angel; Trivino, Monica; Perez-Duenas, Carolina; Acosta, Alberto; Lupianez, Juan

    2010-01-01

    Temporal preparation and impulsivity involve overlapping neural structures (prefrontal cortex) and cognitive functions (response inhibition and time perception), however, their interrelations had not been investigated. We studied such interrelations by comparing the performance of groups with low vs. high non-clinical trait impulsivity during a…

  10. Targeted inhibition of cancer-inflammation

    NARCIS (Netherlands)

    Gomes Coimbra, M.J.

    2012-01-01

    The new paradigm in cancer treatment that aims to inhibit the smoldering inflammatory response in tumors is explored to develop new anticancer treatments. It appears that targeted drug delivery is essential in this concept as high local levels of anti-inflammatory agents are needed to observe the

  11. Fear inhibition in high trait anxiety

    NARCIS (Netherlands)

    Kindt, M.; Soeter, M.

    2014-01-01

    Trait anxiety is recognized as an individual risk factor for the development of anxiety disorders but the neurobiological mechanisms remain unknown. Here we test whether trait anxiety is associated with impaired fear inhibition utilizing the AX+/BX- conditional discrimination procedure that allows f

  12. Serum amyloid P inhibits dermal wound healing

    Science.gov (United States)

    The repair of open wounds depends on granulation tissue formation and contraction, which is primarily mediated by myofibroblasts. A subset of myofibroblasts originates from bone-marrow-derived monocytes which differentiate into fibroblast-like cells called fibrocytes. Serum amyloid P (SAP) inhibits ...

  13. Targeted inhibition of tumor growth and angiogenesis

    NARCIS (Netherlands)

    van der Meel, R.

    2013-01-01

    Two main strategies have been pursued for the development of an effective and targeted anti-cancer treatment. The first strategy comprised the generation of a targeted nanomedicine for the inhibition of tumor cell proliferation by blocking growth factor receptor pathways. The epidermal growth factor

  14. Targeted inhibition of cancer-inflammation

    NARCIS (Netherlands)

    Gomes Coimbra, M.J.

    2012-01-01

    The new paradigm in cancer treatment that aims to inhibit the smoldering inflammatory response in tumors is explored to develop new anticancer treatments. It appears that targeted drug delivery is essential in this concept as high local levels of anti-inflammatory agents are needed to observe the be

  15. Inhibiting Intuitive Thinking in Mathematics Education

    Science.gov (United States)

    Thomas, Michael O. J.

    2015-01-01

    The papers in this issue describe recent collaborative research into the role of inhibition of intuitive thinking in mathematics education. This commentary reflects on this research from a mathematics education perspective and draws attention to some of the challenges that arise in collaboration between research fields with different cultures,…

  16. Nickel inhibits mitochondrial fatty acid oxidation.

    Science.gov (United States)

    Uppala, Radha; McKinney, Richard W; Brant, Kelly A; Fabisiak, James P; Goetzman, Eric S

    2015-08-07

    Nickel exposure is associated with changes in cellular energy metabolism which may contribute to its carcinogenic properties. Here, we demonstrate that nickel strongly represses mitochondrial fatty acid oxidation-the pathway by which fatty acids are catabolized for energy-in both primary human lung fibroblasts and mouse embryonic fibroblasts. At the concentrations used, nickel suppresses fatty acid oxidation without globally suppressing mitochondrial function as evidenced by increased glucose oxidation to CO2. Pre-treatment with l-carnitine, previously shown to prevent nickel-induced mitochondrial dysfunction in neuroblastoma cells, did not prevent the inhibition of fatty acid oxidation. The effect of nickel on fatty acid oxidation occurred only with prolonged exposure (>5 h), suggesting that direct inhibition of the active sites of metabolic enzymes is not the mechanism of action. Nickel is a known hypoxia-mimetic that activates hypoxia inducible factor-1α (HIF1α). Nickel-induced inhibition of fatty acid oxidation was blunted in HIF1α knockout fibroblasts, implicating HIF1α as one contributor to the mechanism. Additionally, nickel down-regulated the protein levels of the key fatty acid oxidation enzyme very long-chain acyl-CoA dehydrogenase (VLCAD) in a dose-dependent fashion. In conclusion, inhibition of fatty acid oxidation by nickel, concurrent with increased glucose metabolism, represents a form of metabolic reprogramming that may contribute to nickel-induced carcinogenesis.

  17. Search Asymmetry, Sustained Attention, and Response Inhibition

    Science.gov (United States)

    Stevenson, Hugh; Russell, Paul N.; Helton, William S.

    2011-01-01

    In the present experiment, we used search asymmetry to test whether the sustained attention to response task is a better measure of response inhibition or sustained attention. Participants performed feature present and feature absent target detection tasks using either a sustained attention to response task (SART; high Go low No-Go) or a…

  18. Target Predictability, Sustained Attention, and Response Inhibition

    Science.gov (United States)

    Carter, Leonie; Russell, Paul N.; Helton, William S.

    2013-01-01

    We examined whether the sustained attention to response task is a better measure of response inhibition or sustained attention. Participants performed a number detection task for 37.3 min using either a Sustained Attention to Response Task (SART; high Go low No-Go) or a more traditionally formatted vigilance task (TFT; high No-Go low Go) response…

  19. Salinomycin, a polyether ionophoric antibiotic, inhibits adipogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Szkudlarek-Mikho, Maria; Saunders, Rudel A. [Department of Medicine, Biochemistry and Cancer Biology, Center for Diabetes and Endocrine Research, College of Medicine, University of Toledo, Toledo, OH 43614 (United States); Yap, Sook Fan [Faculty of Medicine and Health Sciences, Department of Pre-Clinical Sciences, University of Tunku Abdul Rahman (Malaysia); Ngeow, Yun Fong [Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603 (Malaysia); Chin, Khew-Voon, E-mail: khew-voon.chin@utoledo.edu [Department of Medicine, Biochemistry and Cancer Biology, Center for Diabetes and Endocrine Research, College of Medicine, University of Toledo, Toledo, OH 43614 (United States)

    2012-11-30

    Highlights: Black-Right-Pointing-Pointer Salinomycin inhibits preadipocyte differentiation into adipocytes. Black-Right-Pointing-Pointer Salinomycin inhibits transcriptional regulation of adipogenesis. Black-Right-Pointing-Pointer Pharmacological effects of salinomycin suggest toxicity in cancer therapy. -- Abstract: The polyether ionophoric antibiotics including monensin, salinomycin, and narasin, are widely used in veterinary medicine and as food additives and growth promoters in animal husbandry including poultry farming. Their effects on human health, however, are not fully understood. Recent studies showed that salinomycin is a cancer stem cell inhibitor. Since poultry consumption has risen sharply in the last three decades, we asked whether the consumption of meat tainted with growth promoting antibiotics might have effects on adipose cells. We showed in this report that the ionophoric antibiotics inhibit the differentiation of preadipocytes into adipocytes. The block of differentiation is not due to the induction of apoptosis nor the inhibition of cell proliferation. In addition, salinomycin also suppresses the transcriptional activity of the CCAAT/enhancer binding proteins and the peroxisome proliferator-activated receptor {gamma}. These results suggest that the ionophoric antibiotics can be exploited as novel anti-obesity therapeutics and as pharmacological probes for the study of adipose biology. Further, the pharmacological effects of salinomycin could be a harbinger of its toxicity on the adipose tissue and other susceptible target cells in cancer therapy.

  20. Illustrating Enzyme Inhibition Using Gibbs Energy Profiles

    Science.gov (United States)

    Bearne, Stephen L.

    2012-01-01

    Gibbs energy profiles have great utility as teaching and learning tools because they present students with a visual representation of the energy changes that occur during enzyme catalysis. Unfortunately, most textbooks divorce discussions of traditional kinetic topics, such as enzyme inhibition, from discussions of these same topics in terms of…

  1. LOX1 inhibition with small molecules

    DEFF Research Database (Denmark)

    Gousiadou, Chryssoula; Kouskoumvekaki, Irene

    2016-01-01

    the attention as targets and great effort has been made for the discovery and design of suitable inhibitors, to which end both pharmacological and computational methods have been employed. In the present work, using pharmacophore modeling and docking, we attempt to elucidate the inhibition of LOX1 with a new...

  2. Bioluminescence inhibition of bacterial luciferase by aliphatic alcohol, amine and carboxylic acid: inhibition potency and mechanism.

    Science.gov (United States)

    Yamasaki, Shinya; Yamada, Shuto; Takehara, Kô

    2013-01-01

    The inhibitory effects of hydrophobic molecules on the bacterial luciferase, BL, luminescence reaction were analyzed using an electrochemically-controlled BL luminescence system. The inhibition potency of alkyl amines, C(n)NH(2), and fatty acids, C(m)COOH (m = n - 1), on the BL reaction increased with an increase in the alkyl chain-length of these aliphatic compounds. C(m)COOH showed lower inhibition potency than C(n)NH(2) and alkyl alcohols, C(n)OH, data for which have been previously reported. To make clear the inhibition mechanisms of the aliphatic compounds on the BL reaction, the initial rate of the BL reaction was measured and analyzed using the Dixon plot and Cornish-Bowden plot. The C(12)OH inhibited the BL reaction in competition with the substrate C(11)CHO, while C(12)NH(2) and C(11)COOH inhibited in an uncompetitive manner with the C(11)CHO. These results suggest that the alkyl chain-length and the terminal unit of the aliphatic compound determine the inhibition potency and the inhibition mechanism, respectively.

  3. Gold Nanoparticles Inhibit Matrix Metalloproteases without Cytotoxicity.

    Science.gov (United States)

    Hashimoto, M; Sasaki, J I; Yamaguchi, S; Kawai, K; Kawakami, H; Iwasaki, Y; Imazato, S

    2015-08-01

    Nanoparticles (NPs) are currently the focus of considerable attention for dental applications; however, their biological effects have not been fully elucidated. The long-term, slow release of matrix metalloproteases (MMPs) digests collagen fibrils within resin-dentin bonds. Therefore, MMP inhibitors can prolong the durability of resin-dentin bonds. However, there have been few reports evaluating the combined effect of MMP inhibition and the cytotoxic effects of NPs for dentin bonding. The aim of this study was to evaluate MMP inhibition and cytotoxic responses to gold (AuNPs) and platinum nanoparticles (PtNPs) stabilized by polyvinylpyrrolidone (PVP) in cultured murine macrophages (RAW264) by using MMP inhibition assays, measuring cell viability and inflammatory responses (quantitative reverse transcription polymerase chain reaction [RT-qPCR]), and conducting a micromorphological analysis by fluorescence and transmission electron microscopy. Cultured RAW264 cells were exposed to metal NPs at various concentrations (1, 10, 100, and 400 µg/mL). AuNPs and PtNPs markedly inhibited MMP-8 and MMP-9 activity. Although PtNPs were cytotoxic at high concentrations (100 and 400 µg/mL), no cytotoxic effects were observed for AuNPs at any concentration. Transmission electron microscopy images showed a significant nonrandom intercellular distribution for AuNPs and PtNPs, which were mostly observed to be localized in lysosomes but not in the nucleus. RT-qPCR analysis demonstrated inflammatory responses were not induced in RAW264 cells by AuNPs or PtNPs. The cytotoxicity of nanoparticles might depend on the core metal composition and arise from a "Trojan horse" effect; thus, MMP inhibition could be attributed to the surface charge of PVP, which forms the outer coating of NPs. The negative charge of the surface coating of PVP binds to Zn(2+) from the active center of MMPs by chelate binding and results in MMP inhibition. In summary, AuNPs are attractive NPs that effectively

  4. WEE1 inhibition sensitizes osteosarcoma to radiotherapy

    Directory of Open Access Journals (Sweden)

    Helder Marco N

    2011-04-01

    Full Text Available Abstract Background The use of radiotherapy in osteosarcoma (OS is controversial due to its radioresistance. OS patients currently treated with radiotherapy generally are inoperable, have painful skeletal metastases, refuse surgery or have undergone an intralesional resection of the primary tumor. After irradiation-induced DNA damage, OS cells sustain a prolonged G2 cell cycle checkpoint arrest allowing DNA repair and evasion of cell death. Inhibition of WEE1 kinase leads to abrogation of the G2 arrest and could sensitize OS cells to irradiation induced cell death. Methods WEE1 expression in OS was investigated by gene-expression data analysis and immunohistochemistry of tumor samples. WEE1 expression in OS cell lines and human osteoblasts was investigated by Western blot. The effect of WEE1 inhibition on the radiosensitivity of OS cells was assessed by cell viability and caspase activation analyses after combination treatment. The presence of DNA damage was visualized using immunofluorescence microscopy. Cell cycle effects were investigated by flow cytometry and WEE1 kinase regulation was analyzed by Western blot. Results WEE1 expression is found in the majority of tested OS tissue samples. Small molecule drug PD0166285 inhibits WEE1 kinase activity. In the presence of WEE1-inhibitor, irradiated cells fail to repair their damaged DNA, and show higher levels of caspase activation. The inhibition of WEE1 effectively abrogates the irradiation-induced G2 arrest in OS cells, forcing the cells into premature, catastrophic mitosis, thus enhancing cell death after irradiation treatment. Conclusion We show that PD0166285, a small molecule WEE1 kinase inhibitor, can abrogate the G2 checkpoint in OS cells, pushing them into mitotic catastrophe and thus sensitizing OS cells to irradiation-induced cell death. This suggests that WEE1 inhibition may be a promising strategy to enhance the radiotherapy effect in patients with OS.

  5. Inhibition of lung tumorigenesis by tea.

    Science.gov (United States)

    Yang, Chung S; Liao, Jie; Yang, Guang-yu; Lu, Gary

    2005-01-01

    Tea and tea constituents have been shown by different investigators to inhibit lung tumorigenesis in different animal model systems. This includes lung tumorigenesis in A/J mice induced by 4-(methylnitrosamino)-1-(3pyridyl)-1-butanone (NNK), N-nitrosodiethylamine, benzo[a]pyrene, N-nitrosomethylurea, or cisplatin. Inhibition of lung tumorigenesis has also been demonstrated in C3H mice treated with N-nitrosodiethylamine. In most of these experiments, reduction in tumor number and tumor size has been observed in the tea-treated group, and in some experiments, decreased tumor incidence has also been observed. The green tea constituent, epigallocatechin-3-gallate (EGCG), and the black tea constituent, theaflavins, have also been shown to be effective. Black tea preparations have been shown to reduce the incidence and number of spontaneously generated lung adenocarcinomas and rhabdomyosarcoma in A/J mice, as well as inhibit the progression of lung adenoma to adenocarcinoma. The mechanisms for the inhibitory action have not been well elucidated. It may be related to the antiproliferative, proapoptotic, and antiangiogenic activities of tea constituents that have been demonstrated in some experiments. These activities may be a result of the inhibition of key protein kinases involved in signal transduction and cell cycle regulation. Tea catechins, such as EGCG, have been suggested to be the effective components. However, a study suggests that caffeine is the key effective constituent for the inhibitory activity of lung tumorigenesis in Fisher 344 rats by black tea. In many of the experiments, tea consumption resulted in the reduction of body fat and body weight; these factors may also contribute to the inhibition of tumorigenesis.

  6. Degradation and de novo synthesis of D1 protein and psbA transcript in reinhardtii during UV-B inactivation of photosynthesis

    Indian Academy of Sciences (India)

    Ratnesh Haturvedi; Adhey Hyam

    2000-03-01

    UV-B induces intensity and time dependent inhibition of photosynthetic O evolution and PS II electron transport Chlamydomonas reinhardtii chloroplast membranes are rapidly and essential for the repair of damaged PS II as chloramphenicol accelerated UV-B inactivation of photosynthesis and psb for the D1 protein. Cells showing 72% inhibition of PS II protein. This shows that synthesis of D1 protein is not the only component involved in the recovery process. Our events, which in turn may limit the repair of damaged PS II.

  7. Vitis vinifera seeds extract for the modulation of cytosolic factors BAX-α and NF-kB involved in UVB-induced oxidative stress and apoptosis of human skin cells

    Science.gov (United States)

    DECEAN, HANA; FISCHER-FODOR, EVA; TATOMIR, CORINA; PERDE-SCHREPLER, MARIA; SOMFELEAN, LIDIA; BURZ, CLAUDIA; HODOR, TUDOR; ORASAN, REMUS; VIRAG, PIROSKA

    2016-01-01

    Background and aims The depletion of the ozone layer allows overexposure of the skin to UV radiation, which is prolonged due to the increasing life expectancy, together with inappropriate life habits contribute to the increasing incidence of cutaneous malignancies. Plant extracts with antioxidant capacities are frequently employed as a means to protect skin against ultraviolet (UV) radiations, thus preventing skin cancers. In the present study we assessed a red grape seed extract (GSE) potential capacities to reduce ultraviolet B (UVB) radiation-induced reactive oxygen species (ROS) and subsequent apoptosis in a human keratinocytes cell line (HaCaT). We identified molecules and pathways modulated by the GSE through which this may exert its photoprotective effect. Methods The GSE was standardized according to its polyphenolic content and the most important biologically active compounds, such as epigallocatechin and epicatechin, catechin hydrate, procyanidin B and gallic acid were evidenced by high-performance liquid chromatography. According to the plant extract cytotoxicity on the HaCaT cell line, two concentrations were selected for testing from the non-toxic range: GSE1 (37.5 μgEqGA/ml) and GSE2 (75 μgEqGA/ml). The level of ROS was evaluated with CM-H2DCFDA assay, while apoptosis, Bax-α and NF-kβ p65 proteins with ELISA and confirmed by western-blot. Results Both concentrations of the extract decreased the level of ROS in UVB-irradiated keratinocytes (p<0.001), whereas apoptosis and Bax-α pro-apoptotic protein were only reduced by the higher concentration (GSE2). The NF-kB p65 protein level registered increasing values in time after UVB exposure of the cells, while the tested plant extract re-established its level when its smaller concentration was used (GSE1). Conclusion These results encourage further studies on this extract in order to identify other molecules and pathways through which this extract might exert its beneficial effects and also recommend its use as a potential photoprotective agent. PMID:27004028

  8. Intake of high-fat diet stimulates the risk of ultraviolet radiation-induced skin tumors and malignant progression of papillomas to carcinoma in SKH-1 hairless mice

    Energy Technology Data Exchange (ETDEWEB)

    Vaid, Mudit; Singh, Tripti; Prasad, Ram [Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Katiyar, Santosh K., E-mail: skatiyar@uab.edu [Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Birmingham Veterans Affairs Medical Center, Birmingham, AL 35294 (United States)

    2014-01-01

    Previously, we showed that administration of a high-fat diet (HF-diet) to C57BL/6 mice exacerbates their response to short-term UVB radiation-induced inflammation in the skin. To explore the effects of an HF-diet on UVB-induced tumorigenesis, we have used the SKH-1 hairless mouse model in which the mice are exposed to UVB radiation (180 mJ/cm{sup 2}) three times a week for 24 weeks. The development of UVB-induced skin tumors was rapid and the tumor multiplicity and tumor size were significantly higher (P < 0.01–0.005) in the mice fed an HF-diet than the mice fed a control-diet (C-diet). Moreover, the malignant progression of UVB-induced papillomas to carcinomas was higher in HF-diet-fed mice. On analysis of tumors and tumor-uninvolved skin samples from the tumor-bearing mice, we found that administration of an HF-diet significantly enhanced the levels of UVB-induced expression of cyclooxygenase-2 (COX-2), prostaglandin E{sub 2} (P < 0.01), and PGE{sub 2} receptors, and activation of NF-κB in the UVB-exposed skin as well as in tumors. In addition the HF-diet enhanced the expression of proinflammatory cytokines, including tumor necrosis factor-α (P < 0.01), interleukin (IL)-1β (P < 0.01) and IL-6 (P < 0.05) in the UVB-exposed skin as well as in tumors. Western blot analysis revealed that HF-diet enhanced the levels of epidermal cell proliferation, phosphatidylinositol 3-kinase and phosphorylation of Akt at Ser{sup 473} in UVB-exposed skin and skin tumors. Collectively, these data demonstrate that the regular consumption of an HF-diet increases the risk of photocarcinogenesis in mice and that this is associated with enhanced expression of inflammatory mediators in the UVB-exposed skin and tumors. - Highlights: • Consumption of high-fat diet increases UVB-induced skin tumor development in mice. • Intake of high-fat diet stimulates progression of UV-induced papilloma to carcinoma. • Intake of high-fat diet enhances inflammation in UV-exposed skin • Regular

  9. Amiloride inhibits the initiation of Coxsackievirus and poliovirus RNA replication by inhibiting VPg uridylylation.

    Science.gov (United States)

    Ogram, Sushma A; Boone, Christopher D; McKenna, Robert; Flanegan, James B

    2014-09-01

    The mechanism of amiloride inhibition of Coxsackievirus B3 (CVB3) and poliovirus type 1 (PV1) RNA replication was investigated using membrane-associated RNA replication complexes. Amiloride was shown to inhibit viral RNA replication and VPgpUpU synthesis. However, the drug had no effect on polymerase elongation activity during either (-) strand or (+) strand synthesis. These findings indicated that amiloride inhibited the initiation of RNA synthesis by inhibiting VPg uridylylation. In addition, in silico binding studies showed that amiloride docks in the VPg binding site on the back of the viral RNA polymerase, 3D(pol). Since VPg binding at this site on PV1 3D(pol) was previously shown to be required for VPg uridylylation, our results suggest that amiloride inhibits VPg binding to 3D(pol). In summary, our findings are consistent with a model in which amiloride inhibits VPgpUpU synthesis and viral RNA replication by competing with VPg for binding to 3D(pol).

  10. Emotional inhibition: a discourse analysis of disclosure.

    Science.gov (United States)

    Ellis, Darren; Cromby, John

    2012-01-01

    Evidence generated within the emotional disclosure paradigm (EDP) suggests that talking or writing about emotional experiences produces health benefits, but recent meta-analyses have questioned its efficacy. Studies within the EDP typically rely upon a unidimensional and relatively unsophisticated notion of emotional inhibition, and tend to use quantitative forms of content analysis to identify associations between percentages of word types and positive or negative health outcomes. In this article, we use a case study to show how a qualitative discourse analysis has the potential to identify more of the complexity linking the disclosure practices and styles that may be associated with emotional inhibition. This may illuminate the apparent lack of evidence for efficacy of the EDP by enabling more comprehensive theorisations of the variations within it.

  11. Inhibition Controls Asynchronous States of Neuronal Networks

    Science.gov (United States)

    Treviño, Mario

    2016-01-01

    Computations in cortical circuits require action potentials from excitatory and inhibitory neurons. In this mini-review, I first provide a quick overview of findings that indicate that GABAergic neurons play a fundamental role in coordinating spikes and generating synchronized network activity. Next, I argue that these observations helped popularize the notion that network oscillations require a high degree of spike correlations among interneurons which, in turn, produce synchronous inhibition of the local microcircuit. The aim of this text is to discuss some recent experimental and computational findings that support a complementary view: one in which interneurons participate actively in producing asynchronous states in cortical networks. This requires a proper mixture of shared excitation and inhibition leading to asynchronous activity between neighboring cells. Such contribution from interneurons would be extremely important because it would tend to reduce the spike correlation between neighboring pyramidal cells, a drop in redundancy that could enhance the information-processing capacity of neural networks. PMID:27274721

  12. Product inhibition of five Hypocrea jecorina cellulases

    DEFF Research Database (Denmark)

    Murphy, Leigh; Westh, Peter; Bohlin, Christina

    2013-01-01

    on individual cellulases hydrolyzing insoluble cellulose remains insufficient. Such knowledge is necessary to pinpoint and quantify inhibitory weak-links in cellulose hydrolysis, but has proven challenging to come by. Here we show that product inhibition of mono-component cellulases hydrolyzing unmodified...... cellulose may be monitored by calorimetry. The key advantage of this approach is that it directly measures the rate of hydrolysis while being essentially blind to the background of added product. We investigated the five major cellulases from Hypocrea jecorina (anamorph: Tricoderma reesei), Cel7A (formerly......Product inhibition of cellulolytic enzymes has been deemed a critical factor in the industrial saccharification of cellulosic biomass. Several investigations have addressed this problem using crude enzyme preparations or commercial (mixed) cellulase products, but quantitative information...

  13. Direct renin inhibition in chronic kidney disease

    DEFF Research Database (Denmark)

    Persson, Frederik; Rossing, Peter; Parving, Hans-Henrik

    2013-01-01

    that renin inhibition could hold potential for improved treatment in patients with chronic kidney disease, with diabetic nephropathy as an obvious group of patients to investigate, as the activity of the renin-angiotensin-aldosterone system is enhanced in these patients and as there is an unmet need...... early as a beneficial effect was unlikely and there was an increased frequency of side effects. Also in non-diabetic kidney disease a few intervention studies have been carried out, but there is no ongoing hard outcome study. In this review we provide the current evidence for renin inhibition in chronic...... kidney disease by reporting of the studies published so far as well as perspective on the future possibilites....

  14. How x rays inhibit amphibian limb regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Maden, M.; Wallace, H.

    1976-07-01

    The effects of an inhibiting dose of 2,000 rad of x-rays on the regenerating limbs of axolotl larvae have been examined in a histological and cytological study. Particular attention was paid to the mitotic indices of normal and irradiated epidermal and blastemal cells. Both the characteristic pattern of epidermal mitotic stimulation which normally follows amputation and the later increase in blastemal mitoses are suppressed by irradiation. In most cells the effects are permanent, but in a small proportion a mitotic delay is induced and upon subsequent division chromosome damage in the form of micronuclei is revealed. Thus irradiated cells which do divide almost certainly die. These results are discussed in relation to other theories of x-ray inhibition of regeneration with particular reference to the view that irradiated cells can be reactivated.

  15. Sulfate inhibition effect on sulfate reducing bacteria

    Directory of Open Access Journals (Sweden)

    Sulaiman Al Zuhair

    2008-12-01

    Full Text Available There is an increasing interest in the potential of bacterial sulfate reduction as an alternative method for sulfate removal from wastewater. Under anaerobic conditions, sulfate-reducing bacteria (SRB utilize sulfate to oxidize organic compounds and generate sulfide (S2-. SRB were successfully isolated from sludge samples obtained from a local petroleum refinery, and used for sulfate removal. The effects of initial sulfate concentration, temperature and pH on the rate of bacterial growth and anaerobic sulfate removal were investigated and the optimum conditions were identified. The experimental data were used to determine the parameters of two proposed kinetic model, which take into consideration substrate inhibition effect. Keywords: Sulfate Reducing Bacteria, Sulfate, Kinetic Model, Biotreatement, Inhibition Received: 31 August 2008 / Received in revised form: 18 September 2008, Accepted: 18 September 2008 Published online: 28 September 2008

  16. Theobromine inhibits sensory nerve activation and cough.

    Science.gov (United States)

    Usmani, Omar S; Belvisi, Maria G; Patel, Hema J; Crispino, Natascia; Birrell, Mark A; Korbonits, Márta; Korbonits, Dezso; Barnes, Peter J

    2005-02-01

    Cough is a common and protective reflex, but persistent coughing is debilitating and impairs quality of life. Antitussive treatment using opioids is limited by unacceptable side effects, and there is a great need for more effective remedies. The present study demonstrates that theobromine, a methylxanthine derivative present in cocoa, effectively inhibits citric acid-induced cough in guinea-pigs in vivo. Furthermore, in a randomized, double-blind, placebo-controlled study in man, theobromine suppresses capsaicin-induced cough with no adverse effects. We also demonstrate that theobromine directly inhibits capsaicin-induced sensory nerve depolarization of guinea-pig and human vagus nerve suggestive of an inhibitory effect on afferent nerve activation. These data indicate the actions of theobromine appear to be peripherally mediated. We conclude theobromine is a novel and promising treatment, which may form the basis for a new class of antitussive drugs.

  17. Cross-domain inhibition of TACE ectodomain

    DEFF Research Database (Denmark)

    Tape, Christopher J; Willems, Sofie H; Dombernowsky, Sarah L;

    2011-01-01

    Proteolytic release from the cell surface is an essential activation event for many growth factors and cytokines. TNF-a converting enzyme (TACE) is a membrane-bound metalloprotease responsible for solubilizing many pathologically significant membrane substrates and is an attractive therapeutic...... target for the treatment of cancer and arthritis. Prior attempts to antagonize cell-surface TACE activity have focused on small-molecule inhibition of the metalloprotease active site. Given the highly conserved nature of metalloprotease active sites, this paradigm has failed to produce a truly specific...... individual antibody variable domains to desired epitopes. The resulting "cross-domain" human antibody is a previously undescribed selective TACE antagonist and provides a unique alternative to small-molecule metalloprotease inhibition....

  18. Antibiotic inhibition of group I ribozyme function.

    Science.gov (United States)

    von Ahsen, U; Davies, J; Schroeder, R

    1991-09-26

    The discovery of catalytically active RNA has provided the basis for the evolutionary concept of an RNA world. It has been proposed that during evolution the functions of ancient catalytic RNA were modulated by low molecular weight effectors, related to antibiotics, present in the primordial soup. Antibiotics and RNA may have coevolved in the formation of the modern ribosome. Here we report that a set of aminoglycoside antibiotics, which are known to interact with the decoding region of the 16S ribosomal RNA of Escherichia coli, inhibit the second step of splicing of the T4 phage-derived td intron. Thus catalytic RNA seems to interact not only with a mononucleotide and an amino acid, but also with another class of biomolecules, the sugars. Splicing of other group I introns but not group II introns was inhibited. The similarity in affinity and specificity of these antibiotics for group I introns and rRNAs may result from recognition of evolutionarily conserved structures.

  19. AMPA receptor inhibition by synaptically released zinc.

    Science.gov (United States)

    Kalappa, Bopanna I; Anderson, Charles T; Goldberg, Jacob M; Lippard, Stephen J; Tzounopoulos, Thanos

    2015-12-22

    The vast amount of fast excitatory neurotransmission in the mammalian central nervous system is mediated by AMPA-subtype glutamate receptors (AMPARs). As a result, AMPAR-mediated synaptic transmission is implicated in nearly all aspects of brain development, function, and plasticity. Despite the central role of AMPARs in neurobiology, the fine-tuning of synaptic AMPA responses by endogenous modulators remains poorly understood. Here we provide evidence that endogenous zinc, released by single presynaptic action potentials, inhibits synaptic AMPA currents in the dorsal cochlear nucleus (DCN) and hippocampus. Exposure to loud sound reduces presynaptic zinc levels in the DCN and abolishes zinc inhibition, implicating zinc in experience-dependent AMPAR synaptic plasticity. Our results establish zinc as an activity-dependent, endogenous modulator of AMPARs that tunes fast excitatory neurotransmission and plasticity in glutamatergic synapses.

  20. Blocking of potentiation of latent inhibition.

    Science.gov (United States)

    Hall, Geoffrey; Rodriguez, Gabriel

    2011-01-01

    We present a theory of latent inhibition based on the Pearce-Hall (Pearce & Hall, 1980) model for classical conditioning. Its central features are (1) that the associability of a stimulus declines as it comes to predict its consequences and (2) that nonreinforced exposure to a stimulus engages an associative learning process that makes the stimulus an accurate predictor of its consequences (in this case, the occurrence of no event). A formalization of this theory is shown to accommodate the finding that preexposure in compound with another cue can potentiate latent inhibition to the target cue. It further predicts that preexposure to the added cue will eliminate the potentiation effect. An experiment using rats and the flavor-aversion procedure confirmed this prediction.

  1. The Kinetics of Carrier Transport Inhibition

    DEFF Research Database (Denmark)

    Rosenberg, T.; Wilbrandt, Robert Walter

    1962-01-01

    The kinetical treatment of enzymatic carrier transports as given in previous communications has been extended to conditions of inhibition. Various possible types of inhibitors have been considered differing in the site of attack (enzyme or carrier), in the mode of action (competing...... with the substrate for the enzyme or the carrier or for both, competing with the carrier for the enzyme, or non-competitive) and in the ability of penetrating the membrane. Experiments are reported on the inhibition of glucose and fructose transport across the human red cell membrane by phlorizine, phloretine...... the first order asymmetry severalfold (“second order asymmetry”). It was shown that a substrate competitive mode of action involving competition both for the enzyme and for the enzyme-bound carrier will result in a behaviour resembling the observed “second order asymmetry”. It is felt, therefore...

  2. Non-Classical Inhibition of Carbonic Anhydrase

    Science.gov (United States)

    Lomelino, Carrie L.; Supuran, Claudiu T.; McKenna, Robert

    2016-01-01

    Specific isoforms from the carbonic anhydrase (CA) family of zinc metalloenzymes have been associated with a variety of diseases. Isoform-specific carbonic anhydrase inhibitors (CAIs) are therefore a major focus of attention for specific disease treatments. Classical CAIs, primarily sulfonamide-based compounds and their bioisosteres, are examined as antiglaucoma, antiepileptic, antiobesity, antineuropathic pain and anticancer compounds. However, many sulfonamide compounds inhibit all CA isoforms nonspecifically, diluting drug effectiveness and causing undesired side effects due to off-target inhibition. In addition, a small but significant percentage of the general population cannot be treated with sulfonamide-based compounds due to a sulfa allergy. Therefore, CAIs must be developed that are not only isoform specific, but also non-classical, i.e. not based on sulfonamides, sulfamates, or sulfamides. This review covers the classes of non-classical CAIs and the recent advances in the development of isoform-specific inhibitors based on phenols, polyamines, coumarins and their derivatives. PMID:27438828

  3. Inhibition Controls Asynchronous States of Neuronal Networks.

    Science.gov (United States)

    Treviño, Mario

    2016-01-01

    Computations in cortical circuits require action potentials from excitatory and inhibitory neurons. In this mini-review, I first provide a quick overview of findings that indicate that GABAergic neurons play a fundamental role in coordinating spikes and generating synchronized network activity. Next, I argue that these observations helped popularize the notion that network oscillations require a high degree of spike correlations among interneurons which, in turn, produce synchronous inhibition of the local microcircuit. The aim of this text is to discuss some recent experimental and computational findings that support a complementary view: one in which interneurons participate actively in producing asynchronous states in cortical networks. This requires a proper mixture of shared excitation and inhibition leading to asynchronous activity between neighboring cells. Such contribution from interneurons would be extremely important because it would tend to reduce the spike correlation between neighboring pyramidal cells, a drop in redundancy that could enhance the information-processing capacity of neural networks.

  4. Hydroxyapatite growth inhibition by osteopontin hexapeptide sequences.

    Science.gov (United States)

    Silverman, L D; Saadia, M; Ishal, J S; Tishbi, N; Leiderman, E; Kuyunov, I; Recca, B; Reitblat, C; Viswanathan, R

    2010-06-15

    The effects of three acidic hexapeptides on in vitro hydroxyapatite growth were characterized by pH-stat kinetic studies, adsorption isotherms, and molecular modeling. The three peptides, pSDEpSDE, SDESDE, and DDDDDD, are equal-length model compounds for the acidic sequences in osteopontin, a protein that inhibits mineral formation in both calcified and noncalcified tissues. Growth rates from 1.67 mM calcium and 1.00 mM phosphate solution were measured at pH 7.4 and 37 degrees C in 150 mM NaCl. pSDEpSDE was a strong growth inhibitor when preadsorbed onto hydroxyapatite (HA) seeds from > or = 0.67 mM solutions, concentrations where adsorption isotherms showed relatively complete surface coverage. The nonphosphorylated SDESDE control showed no growth inhibition. Although it adsorbed to almost the same extent as pSDEpSDE, it rapidly desorbed under the pH-stat growth conditions while pSDEpSDE did not. DDDDDD exhibited weak inhibition as its concentration was increased and similar adsorption/desorption behavior to pSDEpSDE. Molecular modeling yielded binding energy trends based on simple adsorption of peptides on the [100] surface that were consistent with observed inhibition, but not for the [001] surface. The relatively unfavorable binding energies for peptides on the [001] surface suggest that their absorption will be primarily on the [100] face. The kinetic and adsorption data are consistent with phosphorylation of osteopontin acting to control mineral formation.

  5. An Activation Threshold Model for Response Inhibition

    Science.gov (United States)

    MacDonald, Hayley J.; McMorland, Angus J. C.; Stinear, Cathy M.; Coxon, James P.; Byblow, Winston D.

    2017-01-01

    Reactive response inhibition (RI) is the cancellation of a prepared response when it is no longer appropriate. Selectivity of RI can be examined by cueing the cancellation of one component of a prepared multi-component response. This substantially delays execution of other components. There is debate regarding whether this response delay is due to a selective neural mechanism. Here we propose a computational activation threshold model (ATM) and test it against a classical “horse-race” model using behavioural and neurophysiological data from partial RI experiments. The models comprise both facilitatory and inhibitory processes that compete upstream of motor output regions. Summary statistics (means and standard deviations) of predicted muscular and neurophysiological data were fit in both models to equivalent experimental measures by minimizing a Pearson Chi-square statistic. The ATM best captured behavioural and neurophysiological dynamics of partial RI. The ATM demonstrated that the observed modulation of corticomotor excitability during partial RI can be explained by nonselective inhibition of the prepared response. The inhibition raised the activation threshold to a level that could not be reached by the original response. This was necessarily followed by an additional phase of facilitation representing a secondary activation process in order to reach the new inhibition threshold and initiate the executed component of the response. The ATM offers a mechanistic description of the neural events underlying RI, in which partial movement cancellation results from a nonselective inhibitory event followed by subsequent initiation of a new response. The ATM provides a framework for considering and exploring the neuroanatomical constraints that underlie RI. PMID:28085907

  6. Evidence of dopaminergic processing of executive inhibition.

    Directory of Open Access Journals (Sweden)

    Rajendra D Badgaiyan

    Full Text Available Inhibition of unwanted response is an important function of the executive system. Since the inhibitory system is impaired in patients with dysregulated dopamine system, we examined dopamine neurotransmission in the human brain during processing of a task of executive inhibition. The experiment used a recently developed dynamic molecular imaging technique to detect and map dopamine released during performance of a modified Eriksen's flanker task. In this study, young healthy volunteers received an intravenous injection of a dopamine receptor ligand ((11C-raclopride after they were positioned in the PET camera. After the injection, volunteers performed the flanker task under Congruent and Incongruent conditions in a single scan session. They were required to inhibit competing options to select an appropriate response in the Incongruent but not in the Congruent condition. The PET data were dynamically acquired during the experiment and analyzed using two variants of the simplified reference region model. The analysis included estimation of a number of receptor kinetic parameters before and after initiation of the Incongruent condition. We found increase in the rate of ligand displacement (from receptor sites and decrease in the ligand binding potential in the Incongruent condition, suggesting dopamine release during task performance. These changes were observed in small areas of the putamen and caudate bilaterally but were most significant on the dorsal aspect of the body of left caudate. The results provide evidence of dopaminergic processing of executive inhibition and demonstrate that neurochemical changes associated with cognitive processing can be detected and mapped in a single scan session using dynamic molecular imaging.

  7. Matrix Extracellular Phosphoglycoprotein Inhibits Phosphate Transport

    OpenAIRE

    Marks, J; Churchill, L J; Debnam, E. S.; Unwin, R J

    2008-01-01

    The role of putative humoral factors, known as phosphatonins, in phosphate homeostasis and the relationship between phosphate handling by the kidney and gastrointestinal tract are incompletely understood. Matrix extracellular phosphoglycoprotein (MEPE), one of several candidate phosphatonins, promotes phosphaturia, but whether it also affects intestinal phosphate absorption is unknown. Here, using the in situ intestinal loop technique, we demonstrated that short-term infusion of MEPE inhibits...

  8. Caffeine Inhibits Acetylcholinesterase, But Not Butyrylcholinesterase

    Directory of Open Access Journals (Sweden)

    Petr Dobes

    2013-05-01

    Full Text Available Caffeine is an alkaloid with a stimulant effect in the body. It can interfere in transmissions based on acetylcholine, epinephrine, norepinephrine, serotonin, dopamine and glutamate. Clinical studies indicate that it can be involved in the slowing of Alzheimer disease pathology and some other effects. The effects are not well understood. In the present work, we focused on the question whether caffeine can inhibit acetylcholinesterase (AChE and/or, butyrylcholinesterase (BChE, the two enzymes participating in cholinergic neurotransmission. A standard Ellman test with human AChE and BChE was done for altering concentrations of caffeine. The test was supported by an in silico examination as well. Donepezil and tacrine were used as standards. In compliance with Dixon’s plot, caffeine was proved to be a non-competitive inhibitor of AChE and BChE. However, inhibition of BChE was quite weak, as the inhibition constant, Ki, was 13.9 ± 7.4 mol/L. Inhibition of AChE was more relevant, as Ki was found to be 175 ± 9 µmol/L. The predicted free energy of binding was −6.7 kcal/mol. The proposed binding orientation of caffeine can interact with Trp86, and it can be stabilize by Tyr337 in comparison to the smaller Ala328 in the case of human BChE; thus, it can explain the lower binding affinity of caffeine for BChE with reference to AChE. The biological relevance of the findings is discussed.

  9. Fermentation of lignocellulosic hydrolysates: Inhibition and detoxification

    Energy Technology Data Exchange (ETDEWEB)

    Palmqvist, E.

    1998-02-01

    The ethanol yield and productivity obtained during fermentation of lignocellulosic hydrolysates is decreased due to the presence of inhibiting compounds, such as weak acids, furans and phenolic compounds produced during hydrolysis. Evaluation of the effect of various biological, physical and chemical detoxification treatments by fermentation assays using Saccharomyces cerevisiae was used to characterise inhibitors. Inhibition of fermentation was decreased after removal of the non-volatile compounds, pre-fermentation by the filamentous fungus Trichoderma reesei, treatment with the lignolytic enzyme laccase, extraction with ether, and treatment with alkali. Yeast growth in lignocellulosic hydrolysates was inhibited below a certain fermentation pH, most likely due to high concentrations of undissociated weak acids. The effect of individual compounds were studied in model fermentations. Furfural is reduced to furfuryl alcohol by yeast dehydrogenases, thereby affecting the intracellular redox balance. As a result, acetaldehyde accumulated during furfural reduction, which most likely contributed to inhibition of growth. Acetic acid (10 g 1{sup -1}) and furfural (3 g 1{sup -1}) interacted antagonistically causing decreased specific growth rate, whereas no significant individual or interaction effects were detected by the lignin-derived compound 4-hydroxybenzoic acid (2 g 1{sup -1}). By maintaining a high cell mass density in the fermentor, the process was less sensitive to inhibitors affecting growth and to fluctuations in fermentation pH, and in addition the depletion rate of bioconvertible inhibitors was increased. A theoretical ethanol yield and high productivity was obtained in continuous fermentation of spruce hydrolysate when the cell mass concentration was maintained at a high level by applying cell recirculation 164 refs, 16 figs, 5 tabs

  10. Inhibition of SIRT2 suppresses hepatic fibrosis.

    Science.gov (United States)

    Arteaga, Maribel; Shang, Na; Ding, Xianzhong; Yong, Sherri; Cotler, Scott J; Denning, Mitchell F; Shimamura, Takashi; Breslin, Peter; Lüscher, Bernhard; Qiu, Wei

    2016-06-01

    Liver fibrosis can progress to cirrhosis and result in serious complications of liver disease. The pathogenesis of liver fibrosis involves the activation of hepatic stellate cells (HSCs), the underlying mechanisms of which are not fully known. Emerging evidence suggests that the classic histone deacetylases play a role in liver fibrosis, but the role of another subfamily of histone deacetylases, the sirtuins, in the development of hepatic fibrosis remains unknown. In this study, we found that blocking the activity of sirtuin 2 (SIRT2) by using inhibitors or shRNAs significantly suppressed fibrogenic gene expression in HSCs. We further demonstrated that inhibition of SIRT2 results in the degradation of c-MYC, which is important for HSC activation. In addition, we discovered that inhibition of SIRT2 suppresses the phosphorylation of ERK, which is critical for the stabilization of c-MYC. Moreover, we found that Sirt2 deficiency attenuates the hepatic fibrosis induced by carbon tetrachloride (CCl4) and thioacetamide (TAA). Furthermore, we showed that SIRT2, p-ERK, and c-MYC proteins are all overexpressed in human hepatic fibrotic tissues. These data suggest a critical role for the SIRT2/ERK/c-MYC axis in promoting hepatic fibrogenesis. Inhibition of the SIRT2/ERK/c-MYC axis represents a novel strategy to prevent and to potentially treat liver fibrosis and cirrhosis.

  11. ROCK inhibition prevents early mouse embryo development.

    Science.gov (United States)

    Duan, Xing; Chen, Kun-Lin; Zhang, Yu; Cui, Xiang-Shun; Kim, Nam-Hyung; Sun, Shao-Chen

    2014-08-01

    ROCK is a Rho-GTPase effector that is important for actin assembly and is involved in various cellular functions, including cell contraction, migration, motility, and tumor cell invasion. In this study, we investigated ROCK expression and function during early mouse embryo development. Inhibiting ROCK by Y-27632 treatment at the zygote stage resulted in first cleavage failure, and most embryos failed to develop to the 8-cell stage. When adding Y-27632 at the 8-cell stage, embryos failed to undergo compaction and could not develop into blastocysts. In addition, fluorescence staining intensity analysis indicated that actin expression at blastomere membranes was significantly reduced. After ROCK inhibition, two or more nuclei were observed in a cell, which indicated possible cytokinesis failure. Moreover, after ROCK inhibition with Y-27632, the phosphorylation levels of LIMK1/2, a downstream molecule of ROCK, were decreased at blastomere membranes. Thus, our results showed conserved roles for ROCK in this mammalian embryo model and indicated that a ROCK-LIMK1/2-actin pathway might regulate cleavage and blastocyst formation during early mouse embryo development.

  12. Alpha-amylase inhibition kinetics by caulerpenyne

    Directory of Open Access Journals (Sweden)

    S. CENGIZ

    2010-03-01

    Full Text Available Many algae have important secretions which are generally used for defensive purposes. These secretions take attentions of a lot of researchers who are wondering if these metabolites can be used for medical researches or not. Among these metabolites, caulerpenyne (CYN which is the main metabolite of Caulerpa species, have had an important place in Caulerpa researches since the results related to its determined properties such as cytotoxic, antiviral, antiproliferative and apoptotic effects have been proven by many scientific reports. In the present study, the inhibitory effect of CYN isolated from C. prolifera on alpha-amylase was investigated. The inhibition experiments were done with CYN by spectrophotometric determination method. In order to evaluate the type of inhibition Lineweaver–Burk plot was produced. The results obtained from enzyme kinetic studies exhibited an un-competitive type of inhibition, which is characterized by the difference of Vmax and KM from those of the free enzyme, of alpha-amylase in the presence of CYN. The present study showed that Caulerpa species can be a potential target for producing diabetic drugs in the light of the results obtained for CYN.

  13. Gas hydrate inhibition of drilling fluid additives

    Energy Technology Data Exchange (ETDEWEB)

    Xiaolan, L.; Baojiang, S.; Shaoran, R. [China Univ. of Petroleum, Dongying (China). Inst. of Petroleum Engineering

    2008-07-01

    Gas hydrates that form during offshore well drilling can have adverse impacts on well operational safety. The hydrates typically form in the risers and the annulus between the casing and the drillstring, and can stop the circulation of drilling fluids. In this study, experiments were conducted to measure the effect of drilling fluid additives on hydrate inhibition. Polyalcohols, well-stability control agents, lubricating agents, and polymeric materials were investigated in a stirred tank reactor at temperatures ranging from -10 degree C to 60 degrees C. Pressure, temperature, and torque were used to detect onset points of hydrate formation and dissociation. The inhibitive effect of the additives on hydrate formation was quantified. Phase boundary shifts were measured in terms of temperature difference or sub-cooling gained when chemicals were added to pure water. Results showed that the multiple hydroxyl groups in polyalcohol chemicals significantly inhibited hydrate formation. Polymeric and polyacrylamide materials had only a small impact on hydrate formation, while sulfonated methyl tannins were found to increase hydrate formation. 6 refs., 1 tab., 4 figs.

  14. Inhibition of enveloped viruses infectivity by curcumin.

    Directory of Open Access Journals (Sweden)

    Tzu-Yen Chen

    Full Text Available Curcumin, a natural compound and ingredient in curry, has antiinflammatory, antioxidant, and anticarcinogenic properties. Previously, we reported that curcumin abrogated influenza virus infectivity by inhibiting hemagglutination (HA activity. This study demonstrates a novel mechanism by which curcumin inhibits the infectivity of enveloped viruses. In all analyzed enveloped viruses, including the influenza virus, curcumin inhibited plaque formation. In contrast, the nonenveloped enterovirus 71 remained unaffected by curcumin treatment. We evaluated the effects of curcumin on the membrane structure using fluorescent dye (sulforhodamine B; SRB-containing liposomes that mimic the viral envelope. Curcumin treatment induced the leakage of SRB from these liposomes and the addition of the influenza virus reduced the leakage, indicating that curcumin disrupts the integrity of the membranes of viral envelopes and of liposomes. When testing liposomes of various diameters, we detected higher levels of SRB leakage from the smaller-sized liposomes than from the larger liposomes. Interestingly, the curcumin concentration required to reduce plaque formation was lower for the influenza virus (approximately 100 nm in diameter than for the pseudorabies virus (approximately 180 nm and the vaccinia virus (roughly 335 × 200 × 200 nm. These data provide insights on the molecular antiviral mechanisms of curcumin and its potential use as an antiviral agent for enveloped viruses.

  15. Inhibition of acetylcholinesterase by Tea Tree oil.

    Science.gov (United States)

    Mills, Clive; Cleary, Brian J; Gilmer, John F; Walsh, John J

    2004-03-01

    Pediculosis is a widespread condition reported in schoolchildren. Treatment most commonly involves the physical removal of nits using fine-toothcombs and the chemical treatment of adult lice and eggs with topical preparations. The active constituents of these preparations frequently exert their effects through inhibition of acetylcholinesterase (AChE, EC 3.1.1.7). Increasing resistance to many preparations has led to the search for more effective treatments. Tea Tree oil, otherwise known as Melaleuca oil, has been added to several preparations as an alternative treatment of head lice infestations. In this study two major constituents of Tea Tree oil, 1,8-cineole and terpinen-4-ol, were shown to inhibit acetylcholinesterase at IC50 values (inhibitor concentrations required to give 50% inhibition) of 0.04 and 10.30 mM, respectively. Four samples of Tea Tree oil tested (Tisserand, Body Treats, Main Camp and Irish Health Culture Association Pure Undiluted) showed anticholinesterase activity at IC50 values of 0.05, 0.10, 0.08 and 0.11 microL mL(-1), respectively. The results supported the hypothesis that the insecticidal activity of Tea Tree oil was attributable, in part, to the anticholinesterase activity of Tea Tree oil.

  16. Wnt signaling inhibits CTL memory programming.

    Science.gov (United States)

    Xiao, Zhengguo; Sun, Zhifeng; Smyth, Kendra; Li, Lei

    2013-12-01

    Induction of functional CTLs is one of the major goals for vaccine development and cancer therapy. Inflammatory cytokines are critical for memory CTL generation. Wnt signaling is important for CTL priming and memory formation, but its role in cytokine-driven memory CTL programming is unclear. We found that wnt signaling inhibited IL-12-driven CTL activation and memory programming. This impaired memory CTL programming was attributed to up-regulation of eomes and down-regulation of T-bet. Wnt signaling suppressed the mTOR pathway during CTL activation, which was different to its effects on other cell types. Interestingly, the impaired memory CTL programming by wnt was partially rescued by mTOR inhibitor rapamycin. In conclusion, we found that crosstalk between wnt and the IL-12 signaling inhibits T-bet and mTOR pathways and impairs memory programming which can be recovered in part by rapamycin. In addition, direct inhibition of wnt signaling during CTL activation does not affect CTL memory programming. Therefore, wnt signaling may serve as a new tool for CTL manipulation in autoimmune diseases and immune therapy for certain cancers.

  17. Deubiquitinase inhibition as a cancer therapeutic strategy.

    Science.gov (United States)

    D'Arcy, Padraig; Wang, Xin; Linder, Stig

    2015-03-01

    The ubiquitin proteasome system (UPS) is the main system for controlled protein degradation and a key regulator of fundamental cellular processes. The dependency of cancer cells on a functioning UPS has made this an attractive target for development of drugs that show selectivity for tumor cells. Deubiquitinases (DUBs, ubiquitin isopeptidases) are components of the UPS that catalyze the removal of ubiquitin moieties from target proteins or polyubiquitin chains, resulting in altered signaling or changes in protein stability. A number of DUBs regulate processes associated with cell proliferation and apoptosis, and as such represent candidate targets for cancer therapeutics. The majority of DUBs are cysteine proteases and are likely to be more "druggable" than E3 ligases. Cysteine residues in the active sites of DUBs are expected to be reactive to various electrophiles. Various compounds containing α,β-unsaturated ketones have indeed been demonstrated to inhibit cellular DUB activity. Inhibition of proteasomal cysteine DUB enzymes (i.e. USP14 and UCHL5) can be predicted to be particularly cytotoxic to cancer cells as it leads to blocking of proteasome function and accumulation of proteasomal substrates. We here provide an overall review of DUBs relevant to cancer and of various small molecules which have been demonstrated to inhibit DUB activity.

  18. Phytic Acid Inhibits Lipid Peroxidation In Vitro

    Directory of Open Access Journals (Sweden)

    Alicja Zajdel

    2013-01-01

    Full Text Available Phytic acid (PA has been recognized as a potent antioxidant and inhibitor of iron-catalyzed hydroxyl radical formation under in vitro and in vivo conditions. Therefore, the aim of the present study was to investigate, with the use of HPLC/MS/MS, whether PA is capable of inhibiting linoleic acid autoxidation and Fe(II/ascorbate-induced peroxidation, as well as Fe(II/ascorbate-induced lipid peroxidation in human colonic epithelial cells. PA at 100 μM and 500 μM effectively inhibited the decay of linoleic acid, both in the absence and presence of Fe(II/ascorbate. The observed inhibitory effect of PA on Fe(II/ascorbate-induced lipid peroxidation was lower (10–20% compared to that of autoxidation. PA did not change linoleic acid hydroperoxides concentration levels after 24 hours of Fe(II/ascorbate-induced peroxidation. In the absence of Fe(II/ascorbate, PA at 100 μM and 500 μM significantly suppressed decomposition of linoleic acid hydroperoxides. Moreover, PA at the tested nontoxic concentrations (100 μM and 500 μM significantly decreased 4-hydroxyalkenal levels in Caco-2 cells which structurally and functionally resemble the small intestinal epithelium. It is concluded that PA inhibits linoleic acid oxidation and reduces the formation of 4-hydroxyalkenals. Acting as an antioxidant it may help to prevent intestinal diseases induced by oxygen radicals and lipid peroxidation products.

  19. Phytic acid inhibits lipid peroxidation in vitro.

    Science.gov (United States)

    Zajdel, Alicja; Wilczok, Adam; Węglarz, Ludmiła; Dzierżewicz, Zofia

    2013-01-01

    Phytic acid (PA) has been recognized as a potent antioxidant and inhibitor of iron-catalyzed hydroxyl radical formation under in vitro and in vivo conditions. Therefore, the aim of the present study was to investigate, with the use of HPLC/MS/MS, whether PA is capable of inhibiting linoleic acid autoxidation and Fe(II)/ascorbate-induced peroxidation, as well as Fe(II)/ascorbate-induced lipid peroxidation in human colonic epithelial cells. PA at 100 μM and 500 μM effectively inhibited the decay of linoleic acid, both in the absence and presence of Fe(II)/ascorbate. The observed inhibitory effect of PA on Fe(II)/ascorbate-induced lipid peroxidation was lower (10-20%) compared to that of autoxidation. PA did not change linoleic acid hydroperoxides concentration levels after 24 hours of Fe(II)/ascorbate-induced peroxidation. In the absence of Fe(II)/ascorbate, PA at 100 μM and 500 μM significantly suppressed decomposition of linoleic acid hydroperoxides. Moreover, PA at the tested nontoxic concentrations (100 μM and 500 μM) significantly decreased 4-hydroxyalkenal levels in Caco-2 cells which structurally and functionally resemble the small intestinal epithelium. It is concluded that PA inhibits linoleic acid oxidation and reduces the formation of 4-hydroxyalkenals. Acting as an antioxidant it may help to prevent intestinal diseases induced by oxygen radicals and lipid peroxidation products.

  20. Trace element inhibition of phytase activity.

    Science.gov (United States)

    Santos, T; Connolly, C; Murphy, R

    2015-02-01

    Nowadays, 70 % of global monogastric feeds contains an exogenous phytase. Phytase supplementation has enabled a more efficient utilisation of phytate phosphorous (P) and reduction of P pollution. Trace minerals, such as iron (Fe), zinc (Zn), copper (Cu) and manganese (Mn) are essential for maintaining health and immunity as well as being involved in animal growth, production and reproduction. Exogenous sources of phytase and trace elements are regularly supplemented to monogastric diets and usually combined in a premix. However, the possibility for negative interaction between individual components within the premix is high and is often overlooked. Therefore, this initial study focused on assessing the potential in vitro interaction between inorganic and organic chelated sources of Fe, Zn, Cu and Mn with three commercially available phytase preparations. Additionally, this study has investigated if the degree of enzyme inhibition was dependent of the type of chelated sources. A highly significant relationship between phytase inhibition, trace mineral type as well as mineral source and concentration, p phytases for Fe and Zn, as well as for Cu with E. coli and Aspergillus niger phytases. Different chelate trace mineral sources demonstrated diversifying abilities to inhibit exogenous phytase activity.

  1. Gabapentin inhibits central sensitization during migraine

    Institute of Scientific and Technical Information of China (English)

    Yanbo Zhang; Guo Shao; Wei Zhang; Sijie Li; Jingzhong Niu; Dongmei Hu; Mingfeng Yang; Xunming Ji

    2013-01-01

    Peripheral and central sensitizations are phenomena that occur during migraine. The role of pentin, a migraine preventive drug, on central sensitization remains unclear. In this study, a rat model of migraine was established by electrical stimulation of the trigeminal ganglion, and the an-imals were given intragastric gabapentin. Changes in amino acid content in the cerebrospinal fluid and protein kinase C membrane translocation in the spinal trigeminal nucleus were examined to clarify the mechanisms underlying the efficacy of gabapentin in the treatment of central sensitization during migraine. Electrophysiology, liquid chromatography-mass spectrometry and western blot analysis results revealed that gabapentin reduces neuronal excitability in the spinal nucleus in the trigeminal nerve, decreases excitatory amino acid content and inhibits the activation of protein ki-nase C. This provides evidence that excitatory amino acids and protein kinase C are involved in the formation and maintenance of central sensitization during migraine. Gabapentin inhibits migraine by reducing excitatory amino acid content in the cerebrospinal fluid and inhibiting protein kinase C ac-tivation.

  2. Response inhibition in motor conversion disorder.

    Science.gov (United States)

    Voon, Valerie; Ekanayake, Vindhya; Wiggs, Edythe; Kranick, Sarah; Ameli, Rezvan; Harrison, Neil A; Hallett, Mark

    2013-05-01

    Conversion disorders (CDs) are unexplained neurological symptoms presumed to be related to a psychological issue. Studies focusing on conversion paralysis have suggested potential impairments in motor initiation or execution. Here we studied CD patients with aberrant or excessive motor movements and focused on motor response inhibition. We also assessed cognitive measures in multiple domains. We compared 30 CD patients and 30 age-, sex-, and education-matched healthy volunteers on a motor response inhibition task (go/no go), along with verbal motor response inhibition (color-word interference) and measures of attention, sustained attention, processing speed, language, memory, visuospatial processing, and executive function including planning and verbal fluency. CD patients had greater impairments in commission errors on the go/no go task (P conversion. Patients with nonepileptic seizures, a different form of conversion disorder, are commonly reported to have lower IQ and multiple cognitive deficits. Our results point toward potential differences between conversion disorder subgroups. © 2013 Movement Disorder Society. Copyright © 2013 Movement Disorder Society.

  3. A resorcinarene for inhibition of Aβ fibrillation.

    Science.gov (United States)

    Han, Xu; Park, Jiyong; Wu, Wei; Malagon, Andres; Wang, Lingyu; Vargas, Edgar; Wikramanayake, Athula; Houk, K N; Leblanc, Roger M

    2017-03-01

    Amyloid-β peptides (Aβ) fibrillation is the hallmark of Alzheimer's disease (AD). However, it has been challenging to discover potent agents in order to inhibit Aβ fibrillation. Herein, we demonstrated the effect of resorcinarene on inhibiting Aβ fibrillation in vitro via experimental and computational methods. Aβ were incubated with different concentrations of resorcinarene so as to monitor the kinetics by using thioflavin T binding assay. The results, which were further confirmed by far-UV CD spectroscopy and atomic force microscopy, strongly indicated that the higher concentration of resorcinarene, the more effective the inhibition of Aβ fibrillation. A cytotoxicity study showed that when sea urchin embryos were exposed to the resorcinarene, the majority survived due to the resorcinarene low toxicity. In addition, when the resorcinarene was added, the formation of toxic Aβ 42 species was delayed. Computational studies of Aβ fibrillation, including docking simulations and MD simulations, illustrated that the interaction between inhibitor resorcinarene and Aβ is driven by the non-polar interactions. These studies display a novel strategy for the exploration of promising antiamyloiddogenic agents for AD treatments.

  4. Bioassays for the determination of nitrification inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Grunditz, Camilla

    1999-07-01

    Requirements for nitrogen reduction in wastewater treatment plants were introduced in Sweden in the early 1990's. This was a governmental move to reduce the nitrogen discharges to the Baltic and Kattegat in order to prevent eutrophication. The nitrification process in wastewater treatment plants is performed by nitrifying bacteria. These are susceptible to inhibition and it is of great importance that the influent water does not contain toxic compounds. Therefore, there is a need for assays for the determination of nitrification inhibition. This thesis describes the development and applications of such bioassays. Pure cultures of Nitrosomonas sp. and Nitrobacter sp. were isolated from activated sludge of a wastewater treatment plant. These cultures were used as test organisms in the development of bioassays for nitrification inhibition measurements. The assays are based on two different principles; cell suspensions of the bacteria, performed in test tubes, and mediated amperometric biosensors with the bacteria immobilised. Ammonia oxidation and nitrite oxidation are studied separately without interference from other organisms, which makes it easier to interpret the results. The cell suspension assays were applied to samples of industrial and municipal wastewater. The Nitrosomonas and Nitrobacter assays showed to have different inhibition patterns. A large percentage of the Swedish municipal wastewater treatment plants were found to receive inhibitory influent water, but the inhibition level was generally low. Compared to an assay based on activated sludge, the screening method, the pure culture assays found more samples of influent water strongly inhibitory or stimulating. The highest correlation was found between the screening method and the Nitrosomonas assay. The Nitrobacter assay was found to be the most sensitive method. Assessment of toxicity of a number of chemical substances was studied using the biosensors, together with the cell suspension assays

  5. Antiarrhythmic Mechanisms of SK Channel Inhibition in the Rat Atrium

    DEFF Research Database (Denmark)

    Skibsbye, Lasse; Wang, Xiaodong; Axelsen, Lene Nygaard

    2015-01-01

    remains unclear. OBJECTIVES: We speculated that together with a direct inhibition of repolarizing SK current, the previously observed depolarization of the atrial resting membrane potential (RMP) after SK channel inhibition reduces sodium channel availability thereby prolonging the effective refractory...

  6. Allosteric Partial Inhibition of Monomeric Proteases. Sulfated Coumarins Induce Regulation, not just Inhibition, of Thrombin

    Science.gov (United States)

    Verespy III, Stephen; Mehta, Akul Y.; Afosah, Daniel; Al-Horani, Rami A.; Desai, Umesh R.

    2016-01-01

    Allosteric partial inhibition of soluble, monomeric proteases can offer major regulatory advantages, but remains a concept on paper to date; although it has been routinely documented for receptors and oligomeric proteins. Thrombin, a key protease of the coagulation cascade, displays significant conformational plasticity, which presents an attractive opportunity to discover small molecule probes that induce sub-maximal allosteric inhibition. We synthesized a focused library of some 36 sulfated coumarins to discover two agents that display sub-maximal efficacy (~50%), high potency (150-fold). Michaelis-Menten, competitive inhibition, and site-directed mutagenesis studies identified exosite 2 as the site of binding for the most potent sulfated coumarin. Stern-Volmer quenching of active site-labeled fluorophore suggested that the allosteric regulators induce intermediate structural changes in the active site as compared to those that display ~80–100% efficacy. Antithrombin inactivation of thrombin was impaired in the presence of the sulfated coumarins suggesting that allosteric partial inhibition arises from catalytic dysfunction of the active site. Overall, sulfated coumarins represent first-in-class, sub-maximal inhibitors of thrombin. The probes establish the concept of allosteric partial inhibition of soluble, monomeric proteins. This concept may lead to a new class of anticoagulants that are completely devoid of bleeding. PMID:27053426

  7. Foxp3+ T cells inhibit antitumor immune memory modulated by mTOR inhibition.

    Science.gov (United States)

    Wang, Yanping; Sparwasser, Tim; Figlin, Robert; Kim, Hyung L

    2014-04-15

    Inhibition of mTOR signaling enhances antitumor memory lymphocytes. However, pharmacologic mTOR inhibition also enhances regulatory T-cell (Treg) activity. To counter this effect, Treg control was added to mTOR inhibition in preclinical models. Tregs were controlled with CD4-depleting antibodies because CD4 depletion has high translational potential and already has a well-established safety profile in patients. The antitumor activity of the combination therapy was CD8 dependent and controlled growth of syngeneic tumors even when an adoptive immunotherapy was not used. Lymphocytes resulting from the combination therapy could be transferred into naïve mice to inhibit aggressive growth of lung metastases. The combination therapy enhanced CD8 memory formation as determined by memory markers and functional studies of immune recall. Removal of FoxP3-expressing T lymphocytes was the mechanism underlying immunologic memory formation following CD4 depletion. This was confirmed using transgenic DEREG (depletion of regulatory T cells) mice to specifically remove Foxp3(+) T cells. It was further confirmed with reciprocal studies where stimulation of immunologic memory because of CD4 depletion was completely neutralized by adoptively transferring tumor-specific Foxp3(+) T cells. Also contributing to tumor control, Tregs that eventually recovered following CD4 depletion were less immunosuppressive. These results provide a rationale for further study of mTOR inhibition and CD4 depletion in patients. ©2014 AACR.

  8. A fusion-inhibiting peptide against Rift Valley fever virus inhibits multiple, diverse viruses.

    Directory of Open Access Journals (Sweden)

    Jeffrey W Koehler

    Full Text Available For enveloped viruses, fusion of the viral envelope with a cellular membrane is critical for a productive infection to occur. This fusion process is mediated by at least three classes of fusion proteins (Class I, II, and III based on the protein sequence and structure. For Rift Valley fever virus (RVFV, the glycoprotein Gc (Class II fusion protein mediates this fusion event following entry into the endocytic pathway, allowing the viral genome access to the cell cytoplasm. Here, we show that peptides analogous to the RVFV Gc stem region inhibited RVFV infectivity in cell culture by inhibiting the fusion process. Further, we show that infectivity can be inhibited for diverse, unrelated RNA viruses that have Class I (Ebola virus, Class II (Andes virus, or Class III (vesicular stomatitis virus fusion proteins using this single peptide. Our findings are consistent with an inhibition mechanism similar to that proposed for stem peptide fusion inhibitors of dengue virus in which the RVFV inhibitory peptide first binds to both the virion and cell membranes, allowing it to traffic with the virus into the endocytic pathway. Upon acidification and rearrangement of Gc, the peptide is then able to specifically bind to Gc and prevent fusion of the viral and endocytic membranes, thus inhibiting viral infection. These results could provide novel insights into conserved features among the three classes of viral fusion proteins and offer direction for the future development of broadly active fusion inhibitors.

  9. Zinc ions bind to and inhibit activated protein C

    DEFF Research Database (Denmark)

    Zhu, Tianqing; Ubhayasekera, Wimal; Nickolaus, Noëlle

    2010-01-01

    Zn2+ ions were found to efficiently inhibit activated protein C (APC), suggesting a potential regulatory function for such inhibition. APC activity assays employing a chromogenic peptide substrate demonstrated that the inhibition was reversible and the apparent K I was 13 +/- 2 microM. k cat was ...

  10. SIRT1 controls cell proliferation by regulating contact inhibition.

    Science.gov (United States)

    Cho, Elizabeth H; Dai, Yan

    2016-09-16

    Contact inhibition keeps cell proliferation in check and serves as a built-in protection against cancer development by arresting cell division upon cell-cell contact. Yet the complete mechanism behind this anti-cancer process remains largely unclear. Here we present SIRT1 as a novel regulator of contact inhibition. SIRT1 performs a wide variety of functions in biological processes, but its involvement in contact inhibition has not been explored to date. We used NIH3T3 cells, which are sensitive to contact inhibition, and H460 and DU145 cancer cells, which lack contact inhibition, to investigate the relationship between SIRT1 and contact inhibition. We show that SIRT1 overexpression in NIH3T3 cells overcomes contact inhibition while SIRT1 knockdown in cancer cells restores their lost contact inhibition. Moreover, we demonstrate that p27 protein expression is controlled by SIRT1 in contact inhibition. Overall, our findings underline the critical role of SIRT1 in contact inhibition and suggest SIRT1 inhibition as a potential strategy to suppress cancer cell growth by restoring contact inhibition. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Inhibition of acetylcholinesterase activity by essential oil from Citrus paradisi.

    Science.gov (United States)

    Miyazawa, M; Tougo, H; Ishihara, M

    2001-01-01

    Inhibition of acetylcholinesterase (AChE) activity by essential oils of Citrus paradisi (grapefruit pink in USA) was studied. Inhibition of AChE was measured by the colorimetric method. Nootkatone and auraptene were isolated from C. paradisi oil and showed 17-24% inhibition of AChE activity at the concentration of 1.62 microg/mL.

  12. Inhibition by somatostatin interneurons in olfactory cortex

    Directory of Open Access Journals (Sweden)

    Adam M Large

    2016-08-01

    Full Text Available Inhibitory circuitry plays an integral cortical network activity. The development of transgenic mouse lines targeting unique interneuron classes has significantly advanced our understanding of the functional roles of specific inhibitory circuits in neocortical sensory processing. In contrast, considerably less is known about the circuitry and function of interneuron classes in piriform cortex, a paleocortex responsible for olfactory processing. In this study, we sought to utilize transgenic technology to investigate inhibition mediated by somatostatin (SST interneurons onto pyramidal cells, parvalbumin (PV interneurons and other interneuron classes. As a first step, we characterized the anatomical distributions and intrinsic properties of SST and PV interneurons in four transgenic lines (SST-cre, GIN, PV-cre and G42 that are commonly interbred to investigate inhibitory connectivity. Surprisingly, the distributions SST and PV cell subtypes targeted in the GIN and G42 lines were sparse in piriform cortex compared to neocortex. Moreover, two-thirds of interneurons recorded in the SST-cre line had electrophysiological properties similar to fast spiking (FS interneurons rather than regular (RS or low threshold spiking (LTS phenotypes. Nonetheless, like neocortex, we find that SST-cells broadly inhibit a number of unidentified interneuron classes including putatively identified PV cells and surprisingly, other SST cells. We also confirm that SST-cells inhibit pyramidal cell dendrites and thus, influence dendritic integration of afferent and recurrent inputs to the piriform cortex. Altogether, our findings suggest that somatostatin interneurons play an important role in regulating both excitation and the global inhibitory network during olfactory processing.

  13. Interferon-γ Inhibits Ebola Virus Infection.

    Science.gov (United States)

    Rhein, Bethany A; Powers, Linda S; Rogers, Kai; Anantpadma, Manu; Singh, Brajesh K; Sakurai, Yasuteru; Bair, Thomas; Miller-Hunt, Catherine; Sinn, Patrick; Davey, Robert A; Monick, Martha M; Maury, Wendy

    2015-01-01

    Ebola virus outbreaks, such as the 2014 Makona epidemic in West Africa, are episodic and deadly. Filovirus antivirals are currently not clinically available. Our findings suggest interferon gamma, an FDA-approved drug, may serve as a novel and effective prophylactic or treatment option. Using mouse-adapted Ebola virus, we found that murine interferon gamma administered 24 hours before or after infection robustly protects lethally-challenged mice and reduces morbidity and serum viral titers. Furthermore, we demonstrated that interferon gamma profoundly inhibits Ebola virus infection of macrophages, an early cellular target of infection. As early as six hours following in vitro infection, Ebola virus RNA levels in interferon gamma-treated macrophages were lower than in infected, untreated cells. Addition of the protein synthesis inhibitor, cycloheximide, to interferon gamma-treated macrophages did not further reduce viral RNA levels, suggesting that interferon gamma blocks life cycle events that require protein synthesis such as virus replication. Microarray studies with interferon gamma-treated human macrophages identified more than 160 interferon-stimulated genes. Ectopic expression of a select group of these genes inhibited Ebola virus infection. These studies provide new potential avenues for antiviral targeting as these genes that have not previously appreciated to inhibit negative strand RNA viruses and specifically Ebola virus infection. As treatment of interferon gamma robustly protects mice from lethal Ebola virus infection, we propose that interferon gamma should be further evaluated for its efficacy as a prophylactic and/or therapeutic strategy against filoviruses. Use of this FDA-approved drug could rapidly be deployed during future outbreaks.

  14. Brain hyaluronan binding protein inhibits tumor growth

    Institute of Scientific and Technical Information of China (English)

    高锋; 曹曼林; 王蕾

    2004-01-01

    Background Great efforts have been made to search for the angiogenic inhibitors in avascular tissues. Several proteins isolated from cartilage have been proved to have anti-angiogenic or anti-tumour effects. Because cartilage contains a great amount of hyaluronic acid (HA) oligosaccharides and abundant HA binding proteins (HABP), therefore, we speculated that HABP might be one of the factors regulating vascularization in cartilage or anti-angiogenesis in tumours. The purpose of this research was to evaluale the effects of hyaluronan binding protein on inhibiting tumour growth both in vivo and vitro. Methods A unique protein termed human brain hyaluronan (HA) binding protein (b-HABP) was cloned from human brain cDNA library. MDA-435 human breast cancer cell line was chosen as a transfectant. The in vitro underlying mechanisms were investigated by determining the possibilities of MDA-435/b-HABP colony formation on soft agar, the effects of the transfectant on the proliferation of endothelial cells and the expression levels of caspase 3 and FasL from MDA-435/b-HABP. The in vivo study included tumour growth on the chorioallantoic membrane (CAM) of chicken embryos and nude mice. Results Colony formation assay revealed that the colonies formed by MDA-435/b-HABP were greatly reduced compared to mock transfectants. The conditioned media from MDA-435/b-HABP inhibited the growth of endothelial cells in culture. Caspase 3 and FasL expressions were induced by MDA-435/b-HABP. The size of tumours of MDA-435/b-HABP in both CAM and nude mice was much smaller than that of MDA-435 alone. Conclusions Human brain hyaluronan binding protein (b-HABP) may represent a new kind of naturally existing anti-tumour substance. This brain-derived glycoprotein may block tumour growth by inducing apoptosis of cancer cells or by decreasing angiogenesis in tumour tissue via inhibiting proliferation of endothelial cells.

  15. Reliability of Transcallosal Inhibition in Healthy Adults

    Science.gov (United States)

    Fleming, Melanie K.; Newham, Di J.

    2017-01-01

    Transcallosal inhibition (TCI), assessed using transcranial magnetic stimulation, can provide insight into the neurophysiology of aging and of neurological disorders such as stroke. However, the reliability of TCI using the ipsilateral silent period (iSP) has not been formally assessed, despite its use in longitudinal studies. This study aimed to determine the reliability of iSP onset latency, duration and depth in healthy young and older adults. A sample of 18 younger (mean age 27.7 years, range: 19–42) and 13 older healthy adults (mean age 68.1 years, range: 58–79) attended four sessions whereby the iSP was measured from the first dorsal interosseous (FDI) muscle of each hand. 20 single pulse stimuli were delivered to each primary motor cortex at 80% maximum stimulator output while the participant maintained an isometric contraction of the ipsilateral FDI. The average onset latency, duration of the iSP, and depth of inhibition relative to baseline electromyography activity was calculated for each hand in each session. Intraclass correlation coefficients (ICCs) were calculated for all four sessions, or the first two sessions only. For iSP onset latency the reliability ranged from poor to good. For iSP duration there was moderate to good reliability (ICC > 0.6). Depth of inhibition demonstrated variation in reproducibility depending on which hand was assessed and whether two or four sessions were compared. Bland and Altman analyses showed wide limits of agreement between the first two sessions, particularly for iSP depth. However, there was no systematic pattern to the variability. These results indicate that although iSP duration is reliable in healthy adults, changes in longitudinal studies should be interpreted with caution, particularly for iSP depth. Future studies are needed to determine reliability in clinical populations. PMID:28119588

  16. Interferon-γ Inhibits Ebola Virus Infection.

    Directory of Open Access Journals (Sweden)

    Bethany A Rhein

    Full Text Available Ebola virus outbreaks, such as the 2014 Makona epidemic in West Africa, are episodic and deadly. Filovirus antivirals are currently not clinically available. Our findings suggest interferon gamma, an FDA-approved drug, may serve as a novel and effective prophylactic or treatment option. Using mouse-adapted Ebola virus, we found that murine interferon gamma administered 24 hours before or after infection robustly protects lethally-challenged mice and reduces morbidity and serum viral titers. Furthermore, we demonstrated that interferon gamma profoundly inhibits Ebola virus infection of macrophages, an early cellular target of infection. As early as six hours following in vitro infection, Ebola virus RNA levels in interferon gamma-treated macrophages were lower than in infected, untreated cells. Addition of the protein synthesis inhibitor, cycloheximide, to interferon gamma-treated macrophages did not further reduce viral RNA levels, suggesting that interferon gamma blocks life cycle events that require protein synthesis such as virus replication. Microarray studies with interferon gamma-treated human macrophages identified more than 160 interferon-stimulated genes. Ectopic expression of a select group of these genes inhibited Ebola virus infection. These studies provide new potential avenues for antiviral targeting as these genes that have not previously appreciated to inhibit negative strand RNA viruses and specifically Ebola virus infection. As treatment of interferon gamma robustly protects mice from lethal Ebola virus infection, we propose that interferon gamma should be further evaluated for its efficacy as a prophylactic and/or therapeutic strategy against filoviruses. Use of this FDA-approved drug could rapidly be deployed during future outbreaks.

  17. A novel approach to inhibit bone resorption

    DEFF Research Database (Denmark)

    Panwar, Preety; Søe, Kent; Guido, Rafael VC;

    2016-01-01

    -dihydrotanshinone (DHT1), and the active site inhibitor, odanacatib (ODN), on bone resorption and TGF-ß1 degradation. Cell cultures, Western blot, light and scanning electron microscopy as well as energy dispersive X-ray spectroscopy, molecular modelling and enzymatic assays were used to evaluate the inhibitors. KEY...... RESULTS: DHT1 selectively inhibited the collagenase activity of CatK, without affecting the viability of osteoclasts. Both inhibitors abolished the formation of resorption trenches, with DHT1 having a slightly higher IC50 value than ODN. Maximal reductions of other resorption parameters by DHT1 and ODN...

  18. Linking algal growth inhibition to chemical activity

    DEFF Research Database (Denmark)

    Schmidt, Stine N.; Mayer, Philipp

    to chemical activity, as opposed to e.g. the total concentration. Baseline toxicity (narcosis) for neutral hydrophobic organic compounds has been shown to initiate in the narrow chemical activity range of 0.01 to 0.1. This presentation focuses on linking algal growth inhibition to chemical activity....... High-quality toxicity data are carefully selected from peer-reviewed scientific literature and QSAR databases. This presentation shows how the chemical activity concept can be used to compare and combine toxicity data across compounds and species in order to characterize toxicity – and further how...

  19. Inhibition of intestinal disaccharidase activity by pentoses

    DEFF Research Database (Denmark)

    Halschou-Jensen, Kia

    digestive enzymes. In paper 3, D-xylose and L-arabinose was investigated in vitro and in vivo. This study found that D-xylose and Larabinose inhibit both sucrase and maltase when tested in a Caco-2 cell model. In addition, 13 healthy subjects completed a randomized double-blinded cross-over study......The current health problems regarding the obesity epidemic, development of type 2 diabetes mellitus (T2D) and cardiovascular disease are a major challenge for healthcare systems worldwide.No simple or unique cure has been documented to prevent or treat this major health problem regarding T2D...

  20. Homochiral growth through enantiomeric cross-inhibition

    CERN Document Server

    Brandenburg, A; Höfner, S; Nilsson, M

    2004-01-01

    The stability and conservation properties of a recently proposed polymerization model are studied. The achiral (racemic) solution is linearly unstable once the relevant control parameter (here the fidelity of the catalyst) exceeds a critical value. The growth rate is calculated for different fidelity parameters and cross-inhibition rates. A chirality parameter is defined and shown to be conserved by the nonlinear terms of the model. Finally, a truncated version of the model is used to derive a set of two ordinary differential equations and it is argued that these equations are more realistic than those used in earlier models of that form.

  1. Novel agents inhibit human leukemic cells

    Institute of Scientific and Technical Information of China (English)

    Wei-ping YU; Juan LI

    2012-01-01

    Ouabain (OUA) and pyrithione zinc (PZ) have been proved as the potential drugs for treating acute myeloid leukemia (AML).Selected from a screening among 1040 Food and Drug Administration-approved pharmacological agents,both drugs showability to induce apoptosis of the culturing AML cells,exhibiting the poisoning effect on the cells.Studies also reveal the efficiency of the drugs in inhibiting the growth of human AML cells injected into the mice lacking of immunity and killing primary AML cells from the peripheral blood of AML patients[1].

  2. Basis of pyruvate inhibition in Thiobacillus thiooxidans.

    Science.gov (United States)

    Rao, G S; Berger, L R

    1970-05-01

    Addition of 10(-3)m pyruvic acid to cultures of Thiobacillus thiooxidans, at pH 2.3, results in its rapid intracellular accumulation and in the cessation of sulfur oxidation, CO(2) fixation, and oxygen consumption; at pH 7.0, pyruvate neither inhibits oxygen uptake nor accumulates appreciably intracellularly. Pyruvate does not affect CO(2) fixation in cell-free extracts. The data suggest that the cells of T. thiooxidans are passively permeable to pyruvic acid at low pH. Thus entry of pyruvic acid causes accumulation of pyruvate with a concomitant decrease in intracellular pH.

  3. Research on inhibition of corneal neovascularization

    Directory of Open Access Journals (Sweden)

    Zhang-Hui Yang

    2015-12-01

    Full Text Available Corneal transparency is the basis of the normal physiological functions.However, corneal neovascularization(CNVmay occur in the infection, mechanical and chemical injury or under other pathological conditions,which make the cornea lose original transparency and severe visual impairment. In recent years, along with the development of immunology, molecular biology, biochemistry and other disciplines, there is more in-depth understanding on the CNV, and clinical treatment of CNV has made new breakthroughs. This article provides an overview of the inhibition of CNV.

  4. Quassinoid inhibition of AP-1 function does not correlate with cytotoxicity or protein synthesis inhibition.

    Science.gov (United States)

    Beutler, John A; Kang, Moon-Il; Robert, Francis; Clement, Jason A; Pelletier, Jerry; Colburn, Nancy H; McKee, Tawnya C; Goncharova, Ekaterina; McMahon, James B; Henrich, Curtis J

    2009-03-27

    Several quassinoids were identified in a high-throughput screening assay as inhibitors of the transcription factor AP-1. Further biological characterization revealed that while their effect was not specific to AP-1, protein synthesis inhibition and cell growth assays were inconsistent with a mechanism of simple protein synthesis inhibition. Numerous plant extracts from the plant family Simaroubaceae were also identified in the same screen; bioassay-guided fractionation of one extract (Ailanthus triphylla) yielded two known quassinoids, ailanthinone (3) and glaucarubinone (4), which were also identified in the pure compound screening procedure.

  5. Thymoquinone Inhibits Escherichia coli ATP Synthase and Cell Growth

    OpenAIRE

    2015-01-01

    We examined the thymoquinone induced inhibition of purified F1 or membrane bound F1FO E. coli ATP synthase. Both purified F1 and membrane bound F1FO were completely inhibited by thymoquinone with no residual ATPase activity. The process of inhibition was fully reversible and identical in both membrane bound F1Fo and purified F1 preparations. Moreover, thymoquinone induced inhibition of ATP synthase expressing wild-type E. coli cell growth and non-inhibition of ATPase gene deleted null control...

  6. Identification of a novel component leading to anti-tumor activity besides the major ingredient cordycepin in Cordyceps militaris extract.

    Science.gov (United States)

    Wada, Takeharu; Sumardika, I Wayan; Saito, Shingo; Ruma, I Made Winarsa; Kondo, Eisaku; Shibukawa, Masami; Sakaguchi, Masakiyo

    2017-09-01

    In accordance with our previous study that was carried out to identify novel anti-tumor ingredients, chromatographic separation in combination with an anti-tumor activity assay was used for analysis of Cordyceps militaris extract in this study. Various modes of chromatography including reversed-phase, cation-exchange and anion-exchange were used to separate components of Cordyceps militaris, which showed various chemical properties. Anti-tumor activity of each fraction was assessed by a Hoechst staining-based apoptosis assay using malignant melanoma MeWo cells. By these repeated approaches through chromatographic segregation and cell biological assay, we finally succeeded in identifying the target substance from a certain fraction that included neutral hydrophilic components using a pre-column and post-column chlorine adduct ionization LC-APCI-MS method. The target substance was a mono-carbohydrate, xylitol, that induced apoptotic cell death in MeWo cells but not in normal human OUMS-24 fibroblasts. This is the first study showing that Cordyceps militaris extract contains a large amount of xylitol. Thus, our results will contribute greatly to uncovering the mysterious multifunctional herbal drug Cordyceps militaris as an anti-tumor agent. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. 虫草素抗肿瘤机制研究进展%Research progress of antitumour mechanisms of cordycepin

    Institute of Scientific and Technical Information of China (English)

    丁向萍; 马力

    2009-01-01

    0引言 虫草素是1951年Cunninghan等从Cordyceps militaris原浆液中分离得到的一种物质,命名为虫草素(cordycepin),该成分后被证实为我国中草药冬虫夏草(Cordyceps sinensis)的有效成分,亦被称为蛹虫草素或虫草菌素。

  8. Copper, aluminum, iron and calcium inhibit human acetylcholinesterase in vitro.

    Science.gov (United States)

    Pohanka, Miroslav

    2014-01-01

    Acetylcholinesterase (AChE) is an important part of cholinergic nerves where it participates in termination of neurotransmission. AChE can be inhibited by e.g. some Alzheimer disease drugs, nerve agents, and secondary metabolites. In this work, metal salts aluminum chloride, calcium chloride, cupric chloride, ferric chloride, potassium chloride, magnesium chloride and sodium chloride were tested for their ability to inhibit AChE. Standard Ellman assay based on human recombinant AChE was done and inhibition was measured using Dixon plot. No inhibition was proved for sodium, potassium and magnesium ions. However, aluminum, cupric, ferric and calcium ions were able to inhibit AChE via noncompetitive mechanism of inhibition. Though the inhibition is much weaker when compared to e.g. drugs with noncompetitive mechanism of action, biological relevance of the findings can be anticipated.

  9. A comparator view of Pavlovian and differential inhibition.

    Science.gov (United States)

    Urcelay, Gonzalo P; Miller, Ralph R

    2006-07-01

    In 3 experiments using rats as subjects, the authors varied trial spacing to investigate the conditions under which Pavlovian and differential inhibition are observed. Experiment 1 compared Pavlovian and differential inhibition with spaced training trials. Spaced trials resulted in only the Pavlovian inhibitor passing both summation and retardation tests. Conversely, Experiment 2 compared these 2 types of inhibition with massed training trials. This training resulted in only the differential inhibitor passing both tests for conditioned inhibition. Finally, in Experiment 3 all subjects experienced Pavlovian inhibition training with massed trials. Although this training by itself did not result in behavior indicative of inhibition, subjects that also experienced posttraining extinction of the training context did pass both tests for inhibition. Overall, these results are anticipated by the extended comparator hypothesis (Denniston, Savastano, & Miller, 2001) but are problematic for most contemporary associative learning theories.

  10. Optogenetic and chemogenetic strategies for sustained inhibition of pain

    Science.gov (United States)

    Iyer, Shrivats M.; Vesuna, Sam; Ramakrishnan, Charu; Huynh, Karen; Young, Stephanie; Berndt, Andre; Lee, Soo Yeun; Gorini, Christopher J.; Deisseroth, Karl; Delp, Scott L.

    2016-01-01

    Spatially targeted, genetically-specific strategies for sustained inhibition of nociceptors may help transform pain science and clinical management. Previous optogenetic strategies to inhibit pain have required constant illumination, and chemogenetic approaches in the periphery have not been shown to inhibit pain. Here, we show that the step-function inhibitory channelrhodopsin, SwiChR, can be used to persistently inhibit pain for long periods of time through infrequent transdermally delivered light pulses, reducing required light exposure by >98% and resolving a long-standing limitation in optogenetic inhibition. We demonstrate that the viral expression of the hM4D receptor in small-diameter primary afferent nociceptor enables chemogenetic inhibition of mechanical and thermal nociception thresholds. Finally, we develop optoPAIN, an optogenetic platform to non-invasively assess changes in pain sensitivity, and use this technique to examine pharmacological and chemogenetic inhibition of pain. PMID:27484850

  11. Ehrlich tumor inhibition using doxorubicin containing liposomes.

    Science.gov (United States)

    Elbialy, Nihal Saad; Mady, Mohsen Mahmoud

    2015-04-01

    Ehrlich tumors were grown in female balb mice by subcutaneous injection of Ehrlich ascites carcinoma cells. Mice bearing Ehrlich tumor were injected with saline, DOX in solution or DOX encapsulated within liposomes prepared from DMPC/CHOL/DPPG/PEG-PE (100:100:60:4) in molar ratio. Cytotoxicity assay showed that the IC50 of liposomes containing DOX was greater than that DOX only. Tumor growth inhibition curves in terms of mean tumor size (cm(3)) were presented. All the DOX formulations were effective in preventing tumor growth compared to saline. Treatment with DOX loaded liposomes displayed a pronounced inhibition in tumor growth than treatment with DOX only. Histopathological examination of the entire tumor sections for the various groups revealed marked differences in cellular features accompanied by varying degrees in necrosis percentage ranging from 12% for saline treated mice to 70% for DOX loaded liposome treated mice. The proposed liposomal formulation can efficiently deliver the drug into the tumor cells by endocytosis (or passive diffusion) and lead to a high concentration of DOX in the tumor cells. The study showed that the formulation of liposomal doxorubicin improved the therapeutic index of DOX and had increased anti-tumor activity against Ehrlich tumor models.

  12. In search of lost presynaptic inhibition.

    Science.gov (United States)

    Rudomin, Pablo

    2009-06-01

    This chapter presents an historical review on the development of some of the main findings on presynaptic inhibition. Particular attention is given to recent studies pertaining the differential GABAa control of the synaptic effectiveness of muscle, cutaneous and articular afferents, to some of the problems arising with the identification of the interneurons mediating the GABAergic depolarization of primary afferents (PAD) of muscle afferents, on the influence of the spontaneous activity of discrete sets of dorsal horn neurons on the pathways mediating PAD of muscle and cutaneous afferents, and to the unmasking of the cutaneous-evoked responses in the lumbosacral spinal cord and associated changes in tonic PAD that follow acute and chronic section of cutaneous nerves. The concluding remarks are addressed to several issues that need to be considered to have a better understanding of the functional role of presynaptic inhibition and PAD on motor performance and sensory processing and on their possible contribution to the shaping of a higher coherence between the cortically programmed and the executed movements.

  13. Safrole oxide inhibits angiogenesis by inducing apoptosis.

    Science.gov (United States)

    Zhao, Jing; Miao, Junying; Zhao, Baoxiang; Zhang, Shangli; Yin, Deling

    2005-06-01

    Our previous studies indicate that 3, 4-(methylenedioxy)-1-(2', 3'-epoxypropyl)-benzene (safrole oxide), a newly synthesized compound, induces apoptosis in vascular endothelial cells (VECs) and A549 lung cancer cells. To our knowledge, the inhibition of angiogenesis by safrole oxide has not been reported yet. We report here that cultured rat aorta treated with safrole oxide exhibited a significant microvessel reduction as determined by counting the number of microvessels in a phase contrast microscope. There were more microvessels formed in the presence of A549 lung cancer cells in rat aorta model, while a dramatic inhibition of angiogenesis was obtained by adding 220-450 micromol l(-1) of safrole oxide to the growth medium (Psafrole oxide produced only some abortive endothelial cells but not microvessels. Furthermore, safrole oxide induced antiangiogenic effect in the chorioallantoic membranes (CAM) as a dose dependent manner. Eggs treated with 2-11 micromol 100 microl(-1) per egg of the safrole oxide for 48 h exhibited a significant reduction in blood vessel area of the CAM, a process likely mediated by apoptosis as demonstrated by DNA fragmentation. Our results suggest that safrole oxide has antiangiogenic activity and this effect might occur by induction of cellular apoptosis.

  14. Phenols displaying tyrosinase inhibition from Humulus lupulus.

    Science.gov (United States)

    Kim, Dae Wook; Woo, Hyun Sim; Kim, Jeong Yoon; Ryuk, Jin Ah; Park, Ki Hun; Ko, Byoung Seob

    2016-10-01

    Tyrosinase is the rate-limiting enzyme for the production of melanin and other pigments via the oxidation of l-tyrosine. The methanol extract from Humulus lupulus showed potent inhibition against mushroom tyrosinase. The bioactivity-guided fractionation of this methanol extract resulted in the isolation of seven flavonoids (1-7), identified as xanthohumol (1), 4'-O-methylxanthohumol (2), xanthohumol C (3), flavokawain C (4), xanthoumol B (5), 6-prenylnaringenin (6) and isoxanthohumol (7). All isolated flavonoids (1-7) effectively inhibited the monophenolase (IC50s = 15.4-58.4 µM) and diphenolase (IC50s = 27.1-117.4 µM) activities of tyrosinase. Kinetic studies using Lineweaver-Burk and Dixon-plots revealed that chalcones (1-5) were competitive inhibitors, whereas flavanones (6 and 7) exhibited both mixed and non-competitive inhibitory characteristics. In conclusion, this study is the first to demonstrate that the phenolic phytochemicals of H. lupulus display potent inhibitory activities against tyrosinase.

  15. Therapeutic proteasome inhibition in experimental acute pancreatitis

    Institute of Scientific and Technical Information of China (English)

    Tamás Letoha; Tamás Takács; Liliána Z Fehér; László Pecze; Csaba Somlai; Ilona Varga; József Kaszaki; Gábor Tóth; Csaba Vizier; László Tiszlavicz

    2007-01-01

    AIM: To establish the therapeutic potential of proteasome inhibition, we examined the therapeutic effects of MG132 (Z-Leu-Leu-Leu-aldehyde) in an experimental model of acute pancreatitis.METHODS: Pancreatitis was induced in rats by two hourly intraperitoneal (ip) injections of cholecystokinin octapeptide (CCK; 2 × 100 μg/kg) and the proteasome inhibitor MG132 (10 mg/kg ip) was administered 30 min after the second CCK injection. Animals were sacrificed 4 h after the first injection of CCK.RESULTS: Administering the proteasome inhibitor MG132 (at a dose of 10 mg/kg, ip) 90 min after the onset of pancreatic inflammation induced the expression of cell-protective 72 kDa heat shock protein (HSP72) and decreased DNA-binding of nuclear factor-κB (NF-κB).Furthermore MG132 treatment resulted in milder inflammatory response and cellular damage, as revealed by improved laboratory and histological parameters of pancreatitis and associated oxidative stress.CONCLUSION: Our findings suggest that proteasome inhibition might be beneficial not only for the prevention,but also for the therapy of acute pancreatitis.

  16. Platelets Inhibit Migration of Canine Osteosarcoma Cells.

    Science.gov (United States)

    Bulla, S C; Badial, P R; Silva, R C; Lunsford, K; Bulla, C

    2017-01-01

    The interaction between platelets and tumour cells is important for tumour growth and metastasis. Thrombocytopenia or antiplatelet treatment negatively impact on cancer metastasis, demonstrating potentially important roles for platelets in tumour progression. To our knowledge, there is no information regarding the role of platelets in cancer progression in dogs. This study was designed to test whether canine platelets affected the migratory behaviour of three canine osteosarcoma cell lines and to give insights of molecular mechanisms. Intact platelets, platelet lysate and platelet releasate inhibited the migration of canine osteosarcoma cell lines. Addition of blood leucocytes to the platelet samples did not alter the inhibitory effect on migration. Platelet treatment also significantly downregulated the transcriptional levels of SNAI2 and TWIST1 genes. The interaction between canine platelets or molecules released during platelet activation and these tumour cell lines inhibits their migration, which suggests that canine platelets might antagonize metastasis of canine osteosarcoma. This effect is probably due to, at least in part, downregulation of genes related to epithelial-mesenchymal transition. Copyright © 2016. Published by Elsevier Ltd.

  17. Understanding biocatalyst inhibition by carboxylic acids.

    Science.gov (United States)

    Jarboe, Laura R; Royce, Liam A; Liu, Ping

    2013-09-03

    Carboxylic acids are an attractive biorenewable chemical in terms of their flexibility and usage as precursors for a variety of industrial chemicals. It has been demonstrated that such carboxylic acids can be fermentatively produced using engineered microbes, such as Escherichia coli and Saccharomyces cerevisiae. However, like many other attractive biorenewable fuels and chemicals, carboxylic acids become inhibitory to these microbes at concentrations below the desired yield and titer. In fact, their potency as microbial inhibitors is highlighted by the fact that many of these carboxylic acids are routinely used as food preservatives. This review highlights the current knowledge regarding the impact that saturated, straight-chain carboxylic acids, such as hexanoic, octanoic, decanoic, and lauric acids can have on E. coli and S. cerevisiae, with the goal of identifying metabolic engineering strategies to increase robustness. Key effects of these carboxylic acids include damage to the cell membrane and a decrease of the microbial internal pH. Certain changes in cell membrane properties, such as composition, fluidity, integrity, and hydrophobicity, and intracellular pH are often associated with increased tolerance. The availability of appropriate exporters, such as Pdr12, can also increase tolerance. The effect on metabolic processes, such as maintaining appropriate respiratory function, regulation of Lrp activity and inhibition of production of key metabolites such as methionine, are also considered. Understanding the mechanisms of biocatalyst inhibition by these desirable products can aid in the engineering of robust strains with improved industrial performance.

  18. Understanding biocatalyst inhibition by carboxylic acids

    Directory of Open Access Journals (Sweden)

    Laura R Jarboe

    2013-09-01

    Full Text Available Carboxylic acids are an attractive biorenewable chemical in terms of their flexibility and usage as precursors for a variety of industrial chemicals. It has been demonstrated that such carboxylic acids can be fermentatively produced using engineered microbes, such as Escherichia coli and Saccharomyces cerevisiae. However, like many other attractive biorenewable fuels and chemicals, carboxylic acids become inhibitory to these microbes at concentrations below the desired yield and titer. In fact, their potency as microbial inhibitors is highlighted by the fact that many of these carboxylic acids are routinely used as food preservatives. This review highlights the current knowledge regarding the impact that saturated, straight-chain carboxylic acids, such as hexanoic, octanoic, decanoic and lauric acids can have on E. coli and S. cerevisiae, with the goal of identifying metabolic engineering strategies to increase robustness. Key effects of these carboxylic acids include damage to the cell membrane and a decrease of the microbial internal pH. Certain changes in cell membrane properties, such as composition, fluidity, integrity and hydrophobicity, and intracellular pH are often associated with increased tolerance. The availability of appropriate exporters, such as Pdr12, can also increase tolerance. The effect on metabolic processes, such as maintaining appropriate respiratory function, regulation of Lrp activity and inhibition of production of key metabolites such as methionine, are also considered. Understanding the mechanisms of biocatalyst inhibition by these desirable products can aid in the engineering of robust strains with improved industrial performance.

  19. Calcineurin/NFAT signalling inhibits myeloid haematopoiesis.

    Science.gov (United States)

    Fric, Jan; Lim, Clarice X F; Koh, Esther G L; Hofmann, Benjamin; Chen, Jinmiao; Tay, Hock Soon; Mohammad Isa, Siti Aminah Bte; Mortellaro, Alessandra; Ruedl, Christiane; Ricciardi-Castagnoli, Paola

    2012-04-01

    Nuclear factor of activated T cells (NFAT) comprises a family of transcription factors that regulate T cell development, activation and differentiation. NFAT signalling can also mediate granulocyte and dendritic cell (DC) activation, but it is unknown whether NFAT influences their development from progenitors. Here, we report a novel role for calcineurin/NFAT signalling as a negative regulator of myeloid haematopoiesis. Reconstituting lethally irradiated mice with haematopoietic stem cells expressing an NFAT-inhibitory peptide resulted in enhanced development of the myeloid compartment. Culturing bone marrow cells in media supplemented with Flt3-L in the presence of the calcineurin/NFAT inhibitor Cyclosporin A increased numbers of differentiated DC. Global gene expression analysis of untreated DC and NFAT-inhibited DC revealed differential expression of transcripts that regulate cell cycle and apoptosis. In conclusion, these results provide evidence that calcineurin/NFAT signalling negatively regulates myeloid lineage development. The finding that inhibition of NFAT enhances myeloid development provides a novel insight into understanding how the treatment with drugs targeting calcineurin/NFAT signalling influence the homeostasis of the innate immune system.

  20. Tigecycline inhibits proliferation of Acanthamoeba castellanii.

    Science.gov (United States)

    Jha, Bijay Kumar; Seo, Incheol; Kong, Hyun-Hee; Suh, Seong-Il; Suh, Min-Ho; Baek, Won-Ki

    2015-03-01

    Acanthamoeba is an opportunistic protozoan parasite responsible for different diseases in humans, such as granulomatous amoebic encephalitis and amoebic keratitis. Tigecycline, a third-generation tetracycline antibiotic, has potential activity to treat most of the antibiotic resistant bacterial infections. The effects of tigecycline in eukaryotic cells as well as parasites are less well studied. In the present study, we tested the effects of tigecycline on trophozoites of Acanthamoeba castellanii. The inhibitory effect of tigecycline on Acanthamoeba was determined by resazurin reduction and trypan blue exclusion assays. We found that tigecycline significantly inhibited the growth of Acanthamoeba (46.4 % inhibition at the concentration of 100 μM) without affecting cell viability and induction of encystation, whereas other tetracycline groups of antibiotics such as tetracycline and doxycycline showed no inhibitory effects. Furthermore, tigecycline decreased cellular adenosine triphosphate (ATP) level by 26 % than the control and increased mitochondrial mass, suggesting mitochondrial dysfunction in tigecycline-treated cells. These findings suggest that mitochondrial dysfunction with decreased ATP production might play an important mechanism of tigecycline in suppression of Acanthamoeba proliferation.

  1. Effects of renin inhibition in systemic hypertension.

    Science.gov (United States)

    Anderson, P W; Do, Y S; Schambelan, M; Horton, R; Boger, R S; Luther, R R; Hsueh, W A

    1990-12-01

    The effect of the direct renin inhibitor enalkiren (Abbott Laboratories) was examined in 8 healthy patients with essential hypertension. With an unrestricted sodium diet, plasma renin concentration was inhibited within 10 minutes by intravenous enalkiren and remained essentially undetectable for greater than or equal to 6 hours (11.9 +/- 4 to 1.0 +/- 0.6 ng angiotensin I/ml/hour, p less than 0.05). Mean arterial blood pressure declined gradually (108 +/- 5 to 84 +/- 4 mm Hg, p = 0.02), as did plasma aldosterone concentration (14.4 +/- 3.8 to 4.4 +/- 0.8 ng/dl, p = 0.03), whereas plasma immunoreactive active renin concentration increased progressively (35 +/- 14 to 160 +/- 60 pg/ml, p greater than 0.05). Urinary excretion of the stable metabolite of prostacyclin (6-keto-prostaglandin F1 alpha) decreased slightly, but not significantly (42 +/- 10 to 33 +/- 11 ng/g creatinine, p = 0.13). The addition of a diuretic decreased baseline blood pressure and increased baseline plasma renin and aldosterone values. Blood pressure responses to enalkiren were slightly (though not significantly) greater than those observed before diuretic administration. We conclude that enalkiren is effective in decreasing blood pressure and in inhibiting the renin system, without significantly altering urinary prostacyclin excretion, in patients with essential hypertension. These results suggest that the renin system contributes to the maintenance of elevated blood pressure in some patients with essential hypertension.

  2. Kaempferol inhibits thrombosis and platelet activation.

    Science.gov (United States)

    Choi, Jun-Hui; Park, Se-Eun; Kim, Sung-Jun; Kim, Seung

    2015-08-01

    The objectives of the present study were to investigate whether kaempferol affects pro-coagulant proteinase activity, fibrin clot formation, blood clot and thrombin (or collagen/epinephrine)-stimulated platelet activation, thrombosis, and coagulation in ICR (Imprinting Control Region) mice and SD (Sprague-Dawley) rats. Kaempferol significantly inhibited the enzymatic activities of thrombin and FXa by 68 ± 1.6% and 52 ± 2.4%, respectively. Kaempferol also inhibited fibrin polymer formation in turbidity. Microscopic analysis was performed using a fluorescent conjugate. Kaempferol completely attenuated phosphorylation of extracellular signal-regulated kinase (ERK) 1/2, p38, c-Jun N-terminal kinase (JNK) 1/2, and phosphoinositide 3-kinase (PI3K)/PKB (AKT) in thrombin-stimulated platelets and delayed aggregation time (clotting) by 34.6% in an assay of collagen/epinephrine-stimulated platelet activation. Moreover, kaempferol protected against thrombosis development in 3 animal models, including collagen/epinephrine- and thrombin-induced acute thromboembolism models and an FeCl3-induced carotid arterial thrombus model. The ex vivo anticoagulant effect of kaempferol was further confirmed in ICR mice. This study demonstrated that kaempferol may be clinically useful due to its ability to reduce or prevent thrombotic challenge.

  3. Inhibition of saccades elicits attentional suppression.

    Science.gov (United States)

    Dhawan, Saurabh; Deubel, Heiner; Jonikaitis, Donatas

    2013-05-17

    Visuospatial attention has been shown to have a central role in planning and generation of saccades but what role, if any, it plays in inhibition of saccades remains unclear. In this study, we used an oculomotor delayed match- or nonmatch-to-sample task in which a cued location has to be encoded and memorized for one of two very different goals-to plan a saccade to it or to avoid making a saccade to it. We measured the spatial allocation of attention during the delay and found that while marking a location as a future saccade target resulted in an attentional benefit at that location, marking it as forbidden to saccades led to an attentional cost. Additionally, saccade trajectories were found to deviate away more from the "don't look" location than from a saccade-irrelevant distractor confirming greater inhibition of an actively forbidden location in oculomotor programming. Our finding that attention is suppressed at locations forbidden to saccades confirms and complements the claim of a selective and obligatory coupling between saccades and attention-saccades at the memorized location could neither be planned nor suppressed independent of a corresponding effect on attentional performance.

  4. Targeting Sphingosine Kinase-1 To Inhibit Melanoma

    Science.gov (United States)

    Madhunapantula, SubbaRao V.; Hengst, Jeremy; Gowda, Raghavendra; Fox, Todd E.; Yun, Jong K; Robertson, Gavin P.

    2012-01-01

    SUMMARY Resistance to therapies develops rapidly for melanoma leading to more aggressive disease. Therefore, agents are needed that specifically inhibit proteins or pathways controlling the development of this disease, which can be combined, dependent on genes deregulated in a particular patient’s tumors. This study shows that elevated sphingosine-1-phosphate (S-1-P) levels resulting from increased activity of sphingosine kinase-1 (SPHK1) occur in advanced melanomas. Targeting SPHK1 using siRNA decreased anchorage dependent and independent growth as well as sensitized melanoma cells to apoptosis inducing agents. Pharmacological SPHK1 inhibitors SKI-I but not SKI-II decreased S-1-P content, elevated ceramide levels, caused a G2-M block and induced apoptotic cell death in melanomas. Targeting SPHK1 using siRNA or the pharmacological agent called SKI-I, decreased the levels of pAKT. Furthermore, SKI-I inhibited the expression of CYCLIN D1 protein and increased the activity of caspase-3/7, which in turn led to the degradation of PARP. In animals, SKI-I but not SKI-II retarded melanoma growth by 25-40%. Thus, targeting SPHK1 using siRNAs or SKI-I has therapeutic potential for melanoma treatment either alone or in combination with other targeted agents. PMID:22236408

  5. Diacylglycerol Kinase Inhibition and Vascular Function.

    Science.gov (United States)

    Choi, Hyehun; Allahdadi, Kyan J; Tostes, Rita C A; Webb, R Clinton

    2009-01-01

    Diacylglycerol kinases (DGKs), a family of lipid kinases, convert diacylglycerol (DG) to phosphatidic acid (PA). Acting as a second messenger, DG activates protein kinase C (PKC). PA, a signaling lipid, regulates diverse functions involved in physiological responses. Since DGK modulates two lipid second messengers, DG and PA, regulation of DGK could induce related cellular responses. Currently, there are 10 mammalian isoforms of DGK that are categorized into five groups based on their structural features. These diverse isoforms of DGK are considered to activate distinct cellular functions according to extracellular stimuli. Each DGK isoform is thought to play various roles inside the cell, depending on its subcellular localization (nuclear, ER, Golgi complex or cytoplasm). In vascular smooth muscle, vasoconstrictors such as angiotensin II, endothelin-1 and norepinephrine stimulate contraction by increasing inositol trisphosphate (IP(3)), calcium, DG and PKC activity. Inhibition of DGK could increase DG availability and decrease PA levels, as well as alter intracellular responses, including calcium-mediated and PKC-mediated vascular contraction. The purpose of this review is to demonstrate a role of DGK in vascular function. Selective inhibition of DGK isoforms may represent a novel therapeutic approach in vascular dysfunction.

  6. Chromosome tips damaged in anaphase inhibit cytokinesis.

    Directory of Open Access Journals (Sweden)

    Norman M Baker

    Full Text Available Genome maintenance is ensured by a variety of biochemical sensors and pathways that repair accumulated damage. During mitosis, the mechanisms that sense and resolve DNA damage remain elusive. Studies have demonstrated that damage accumulated on lagging chromosomes can activate the spindle assembly checkpoint. However, there is little known regarding damage to DNA after anaphase onset. In this study, we demonstrate that laser-induced damage to chromosome tips (presumptive telomeres in anaphase of Potorous tridactylis cells (PtK2 inhibits cytokinesis. In contrast, equivalent irradiation of non-telomeric chromosome regions or control irradiations in either the adjacent cytoplasm or adjacent to chromosome tips near the spindle midzone during anaphase caused no change in the eventual completion of cytokinesis. Damage to only one chromosome tip caused either complete absence of furrow formation, a prolonged delay in furrow formation, or furrow regression. When multiple chromosome tips were irradiated in the same cell, the cytokinesis defects increased, suggesting a potential dose-dependent mechanism. These results suggest a mechanism in which dysfunctional telomeres inhibit mitotic exit.

  7. Ribosome Inactivating Proteins from Plants Inhibiting Viruses

    Institute of Scientific and Technical Information of China (English)

    Inderdeep Kaur; R C Gupta; Munish Puri

    2011-01-01

    Many plants contain ribosome inactivating proteins (RIPs) with N-glycosidase activity,which depurinate large ribosomal RNA and arrest protein synthesis.RIPs so far tested inhibit replication of mRNA as well as DNA viruses and these proteins,isolated from plants,are found to be effective against a broad range of viruses such as human immunodeficiency virus (HIV),hepatitis B virus (HBV) and herpes simplex virus (HSV).Most of the research work related to RIPs has been focused on antiviral activity against HIV; however,the exact mechanism of antiviral activity is still not clear.The mechanism of antiviral activity was thought to follow inactivation of the host cell ribosome,leading to inhibition of viral protein translation and host cell death.Enzymatic activity of RIPs is not hmited to depurination of the large rRNA,in addition they can depurinate viral DNA as well as RNA.Recently,Phase Ⅰ/Ⅱ clinical trials have demonstrated the potential use of RIPs for treating patients with HIV disease.The aim of this review is to focus on various RIPs from plants associated with anti-HIV activity.

  8. The inhibitory effect of an extract of Sanguisorba officinalis L. on ultraviolet B-induced pigmentation via the suppression of endothelin-converting enzyme-1{alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Hachiya, Akira; Kobayashi, Akemi; Ohuchi, Atsushi; Kitahara, Takashi; Takema, Yoshinori [Kao Biological Science Lab., Ichikai, Tochigi (Japan)

    2001-06-01

    Endothelin-1 (ET-1) has been reported to be expressed in human epidermis at both the gene and protein levels. ET-1 plays a pivotal role in ultraviolet B (UVB)-induced pigmentation due to its accentuated secretion after UVB irradiation and its function as a mitogen and as a melanogen for human melanocytes. We have recently found that endothelin-converting enzyme (ECE)-1{alpha} plays a constitutive role in the secretion of ET-1 by human keratinocytes and that an extract of Sanguisorba officinalis L. inhibits ECE activity in human endothelial cells, which predominantly express ECE-1{alpha}. In this report, to clarify the potential use of this botanical extract as a whitening agent, we examined whether this extract inhibits UVB-induced pigmentation in vivo. When this extract was applied to human keratinocytes after UVB irradiation, secretion of ET-1 by those cells was reduced, and this was accompanied by a concomitant increase in the secretion of inactive precursor Big endothelin-1. When hairless mice were exposed to UVB light and were treated with the extract, it suppressed the induction of ET-1 in the UVB-irradiated epidermis. In the course of UVB-induced pigmentation of brownish guinea pig skin, this extract significantly diminished pigmentation in UVB-exposed areas. These findings indicate that ECE-1{alpha} in keratinocytes plays a pivotal role in the induction of pigmentation following UVB irradiation and that an extract of S. officinalis, which inhibits ET-1 production in human keratinocytes, is a good ingredient for a whitening agent. (author)

  9. Inhibition by acrolein of light-induced stomatal opening through inhibition of inward-rectifying potassium channels in Arabidopsis thaliana.

    Science.gov (United States)

    Islam, Md Moshiul; Ye, Wenxiu; Matsushima, Daiki; Khokon, Md Atiqur Rahman; Munemasa, Shintaro; Nakamura, Yoshimasa; Murata, Yoshiyuki

    2015-01-01

    Acrolein is a reactive α,β-unsaturated aldehyde derived from lipid peroxides, which are produced in plants under a variety of stress. We investigated effects of acrolein on light-induced stomatal opening using Arabidopsis thaliana. Acrolein inhibited light-induced stomatal opening in a dose-dependent manner. Acrolein at 100 μM inhibited plasma membrane inward-rectifying potassium (Kin) channels in guard cells. Acrolein at 100 μM inhibited Kin channel KAT1 expressed in a heterologous system using Xenopus leaves oocytes. These results suggest that acrolein inhibits light-induced stomatal opening through inhibition of Kin channels in guard cells.

  10. Distinct Neural Correlates for Two Types of Inhibition in Bilinguals: Response Inhibition versus Interference Suppression

    Science.gov (United States)

    Luk, Gigi; Anderson, John A. E.; Craik, Fergus I. M.; Grady, Cheryl; Bialystok, Ellen

    2010-01-01

    To examine the effects of bilingualism on cognitive control, we studied monolingual and bilingual young adults performing a flanker task with functional MRI. The trial types of primary interest for this report were incongruent and no-go trials, representing interference suppression and response inhibition, respectively. Response times were similar…

  11. Ketoconazole inhibits the cellular uptake of anandamide via inhibition of FAAH at pharmacologically relevant concentrations.

    Directory of Open Access Journals (Sweden)

    Emmelie Björklund

    Full Text Available BACKGROUND: The antifungal compound ketoconazole has, in addition to its ability to interfere with fungal ergosterol synthesis, effects upon other enzymes including human CYP3A4, CYP17, lipoxygenase and thromboxane synthetase. In the present study, we have investigated whether ketoconazole affects the cellular uptake and hydrolysis of the endogenous cannabinoid receptor ligand anandamide (AEA. METHODOLOGY/PRINCIPAL FINDINGS: The effects of ketoconazole upon endocannabinoid uptake were investigated using HepG2, CaCo2, PC-3 and C6 cell lines. Fatty acid amide hydrolase (FAAH activity was measured in HepG2 cell lysates and in intact C6 cells. Ketoconazole inhibited the uptake of AEA by HepG2 cells and CaCo2 cells with IC50 values of 17 and 18 µM, respectively. In contrast, it had modest effects upon AEA uptake in PC-3 cells, which have a low expression of FAAH. In cell-free HepG2 lysates, ketoconazole inhibited FAAH activity with an IC50 value (for the inhibitable component of 34 µM. CONCLUSIONS/SIGNIFICANCE: The present study indicates that ketoconazole can inhibit the cellular uptake of AEA at pharmacologically relevant concentrations, primarily due to its effects upon FAAH. Ketoconazole may be useful as a template for the design of dual-action FAAH/CYP17 inhibitors as a novel strategy for the treatment of prostate cancer.

  12. 3-Bromopyruvate inhibits human gastric cancer tumor growth in nude mice via the inhibition of glycolysis.

    Science.gov (United States)

    Xian, Shu-Lin; Cao, Wei; Zhang, Xiao-Dong; Lu, Yun-Fei

    2015-02-01

    Tumor cells primarily depend upon glycolysis in order to gain energy. Therefore, the inhibition of glycolysis may inhibit tumor growth. Our previous study demonstrated that 3-bromopyruvate (3-BrPA) inhibited gastric cancer cell proliferation in vitro. However, the ability of 3-BrPA to suppress tumor growth in vivo, and its underlying mechanism, have yet to be elucidated. The aim of the present study was to investigate the inhibitory effect of 3-BrPA in an animal model of gastric cancer. It was identified that 3-BrPA exhibited strong inhibitory effects upon xenograft tumor growth in nude mice. In addition, the antitumor function of 3-BrPA exhibited a dose-effect association, which was similar to that of the chemotherapeutic agent, 5-fluorouracil. Furthermore, 3-BrPA exhibited low toxicity in the blood, liver and kidneys of the nude mice. The present study hypothesized that the inhibitory effect of 3-BrPA is achieved through the inhibition of hexokinase activity, which leads to the downregulation of B-cell lymphoma 2 (Bcl-2) expression, the upregulation of Bcl-2-associated X protein expression and the subsequent activation of caspase-3. These data suggest that 3-BrPA may be a novel therapy for the treatment of gastric cancer.

  13. Effects of lorazepam on short latency afferent inhibition and short latency intracortical inhibition in humans.

    Science.gov (United States)

    Di Lazzaro, V; Oliviero, A; Saturno, E; Dileone, M; Pilato, F; Nardone, R; Ranieri, F; Musumeci, G; Fiorilla, T; Tonali, P

    2005-04-15

    Experimental studies have demonstrated that the GABAergic system modulates acetylcholine release and, through GABA(A) receptors, tonically inhibits cholinergic activity. Little is known about the effects of GABA on the cholinergic activity in the human central nervous system. In vivo evaluation of some cholinergic circuits of the human brain has recently been introduced using a transcranial magnetic stimulation (TMS) protocol based on coupling peripheral nerve stimulation with TMS of the motor cortex. Peripheral nerve inputs have an inhibitory effect on motor cortex excitability at short intervals (short latency afferent inhibition, SAI). We investigated whether GABA(A) activity enhancement by lorazepam modifies SAI. We also evaluated the effects produced by lorazepam on a different TMS protocol of cortical inhibition, the short interval intracortical inhibition (SICI), which is believed to be directly related to GABA(A) activity. In 10 healthy volunteers, the effects of lorazepam were compared with those produced by quetiapine, a psychotropic drug with sedative effects with no appreciable affinity at cholinergic muscarinic and benzodiazepine receptors, and with those of a placebo using a randomized double-blind study design. Administration of lorazepam produced a significant increase in SICI (F(3,9) = 3.19, P = 0.039). In contrast to SICI, SAI was significantly reduced by lorazepam (F(3,9) = 9.39, P = 0.0002). Our findings demonstrate that GABA(A) activity enhancement determines a suppression of SAI and an increase of SICI.

  14. Inhibition of the V-ATPase by Archazolid A - a new strategy to inhibit EMT.

    Science.gov (United States)

    Merk, Henriette; Messer, Philipp; Ardelt, Maximilian A; Lamb, Don C; Zahler, Stefan; Müller, Rolf; Vollmar, Angelika M; Pachmayr, Johanna

    2017-08-03

    Epithelial-mesenchymal transition (EMT) induces tumor-initiating cells (TICs) which account for tumor recurrence, metastasis and therapeutic resistance. Strategies to interfere with EMT are rare but urgently needed to improve cancer therapy. By using the myxobacterial natural compound Archazolid A as a tool, we elucidate the V-ATPase, a multimeric proton pump that regulates lysosomal acidification, as a crucial player in EMT and identify the inhibition of V-ATPase by Archazolid A as promising strategy to block EMT. Genetic knockdown and pharmacologic inhibition of the V-ATPase by Archazolid A interfere with the EMT process and inhibit TIC generation, as shown by a reduced formation of mammospheres and decreased cell motility. As underlying mechanism, V-ATPase-inhibition by Archazolid A disturbs the turnover of E-cadherin: Archazolid abrogates E-cadherin loss during EMT by interfering with its internalization and recycling. Our study elucidates V-ATPase as essential player in EMT by regulating E-cadherin turnover.  Archazolid A is suggested as a promising therapeutic agent to block EMT and the generation of TICs. Copyright ©2017, American Association for Cancer Research.

  15. Doxycycline inhibits leukemic cell migration via inhibition of matrix metalloproteinases and phosphorylation of focal adhesion kinase.

    Science.gov (United States)

    Wang, Chunhuai; Xiang, Ru; Zhang, Xiangzhong; Chen, Yunxian

    2015-09-01

    Doxycycline, a tetracycline-based antibiotic, has been reported to attenuate melanoma cell migration through inhibiting the focal adhesion kinase (FAK) signaling pathway. However, it remains to be elucidated whether doxycycline exerts this effect on leukemia cell migration. The present study aimed to examine the role of doxycycline in leukemia cell migration. The invasion capacities of the human leukemia cell lines KG1a (acute myelogenous leukemia) and K562 (chronic myelogenous leukemia) were evaluated using Matrigel® matrix‑coated Transwell® chamber assays; leukemic cell lines treated with doxycycline (1 µg/ml) or anti‑β1‑integrin antibodies were added to the upper chamber, while untreated cells were included as controls. Reverse transcription quantitative polymerase chain reaction was performed in order to further understand the influence of doxycycline treatment on the expression of FAK and gelatinases in the KG1a and K562 leukemic cell lines. In addition, FAK protein expression and phosphorylation were determined using western blot analysis in order to investigate the mechanism by which doxycycline inhibited leukemic cell migration. The results revealed that doxycycline treatment significantly attenuated the migration of KG1a and K562 cells, which was demonstrated to be associated with inhibition of the expression and phosphorylation of FAK. In addition, doxycycline treatment inhibited matrix metalloproteinase (MMP)‑2 and MMP‑9 expression. Furthermore, incubation with blocking anti‑β1‑integrin antibodies had an analogous inhibitory effect on leukemic cell migration to that of doxycycline. In conclusion, the results of the present study suggested that doxycycline attenuated leukemic cell migration through inhibiting the FAK signaling pathway. Therefore, doxycycline may have potential for use as a novel strategy for the treatment of leukemia.

  16. Equol inhibits growth, induces atresia, and inhibits steroidogenesis of mouse antral follicles in vitro.

    Science.gov (United States)

    Mahalingam, Sharada; Gao, Liying; Gonnering, Marni; Helferich, William; Flaws, Jodi A

    2016-03-15

    Equol is a non-steroidal estrogen metabolite produced by microbial conversion of daidzein, a major soy isoflavone, in the gut of some humans and many animal species. Isoflavones and their metabolites can affect endogenous estradiol production, action, and metabolism, potentially influencing ovarian follicle function. However, no studies have examined the effects of equol on intact ovarian antral follicles, which are responsible for sex steroid synthesis and further development into ovulatory follicles. Thus, the present study tested the hypothesis that equol inhibits antral follicle growth, increases follicle atresia, and inhibits steroidogenesis in the adult mouse ovary. To test this hypothesis, antral follicles isolated from adult CD-1 mice were cultured with vehicle control (dimethyl sulfoxide; DMSO) or equol (600 nM, 6 μM, 36 μM, and 100 μM) for 48 and 96 h. Every 24h, follicle diameters were measured to monitor growth. At 48 and 96 h, the culture medium was subjected to measurement of hormone levels, and the cultured follicles were subjected to gene expression analysis. Additionally, follicles were histologically evaluated for signs of atresia after 96 h of culture. The results indicate that equol (100 μM) inhibited follicle growth, altered the mRNA levels of bcl2-associated X protein and B cell leukemia/lymphoma 2, and induced follicle atresia. Further, equol decreased the levels of estradiol, testosterone, androstenedione, and progesterone, and it decreased mRNA levels of cholesterol side-chain cleavage, steroid 17-α-hydroxalase, and aromatase. Collectively, these data indicate that equol inhibits growth, increases atresia, and inhibits steroidogenesis of cultured mouse antral follicles.

  17. Neural and behavioral mechanisms of proactive and reactive inhibition.

    Science.gov (United States)

    Meyer, Heidi C; Bucci, David J

    2016-10-01

    Response inhibition is an important component of adaptive behavior. Substantial prior research has focused on reactive inhibition, which refers to the cessation of a motor response that is already in progress. More recently, a growing number of studies have begun to examine mechanisms underlying proactive inhibition, whereby preparatory processes result in a response being withheld before it is initiated. It has become apparent that proactive inhibition is an essential component of the overall ability to regulate behavior and has implications for the success of reactive inhibition. Moreover, successful inhibition relies on learning the meaning of specific environmental cues that signal when a behavioral response should be withheld. Proactive inhibitory control is mediated by stopping goals, which reflect the desired outcome of inhibition and include information about how and when inhibition should be implemented. However, little is known about the circuits and cellular processes that encode and represent features in the environment that indicate the necessity for proactive inhibition or how these representations are implemented in response inhibition. In this article, we will review the brain circuits and systems involved in implementing inhibitory control through both reactive and proactive mechanisms. We also comment on possible cellular mechanisms that may contribute to inhibitory control processes, noting that substantial further research is necessary in this regard. Furthermore, we will outline a number of ways in which the temporal dynamics underlying the generation of the proactive inhibitory signal may be particularly important for parsing out the neurobiological correlates that contribute to the learning processes underlying various aspects of inhibitory control.

  18. Ubiquitylation of terminal deoxynucleotidyltransferase inhibits its activity.

    Directory of Open Access Journals (Sweden)

    So Maezawa

    Full Text Available Terminal deoxynucleotidyltransferase (TdT, which template-independently synthesizes DNA during V(DJ recombination in lymphoid cells, is ubiquitylated by a BPOZ-2/Cul3 complex, as the ubiquitin ligase, and then degraded by the 26 S proteasome. We show here that TdT is ubiquitylated by the Cul3-based ubiquitylation system in vitro. Because TdT could also be ubiquitylated in the absence of Cul/BPOZ-2, we determined that it could also be directly ubiquitylated by the E2 proteins UbcH5a/b/c and UbcH6, E3-independently. Furthermore, the ubiquitylated TdT inhibited its nucleotidyltransferase activity.

  19. Inhibiting bacterial toxins by channel blockage.

    Science.gov (United States)

    Bezrukov, Sergey M; Nestorovich, Ekaterina M

    2016-03-01

    Emergent rational drug design techniques explore individual properties of target biomolecules, small and macromolecule drug candidates, and the physical forces governing their interactions. In this minireview, we focus on the single-molecule biophysical studies of channel-forming bacterial toxins that suggest new approaches for their inhibition. We discuss several examples of blockage of bacterial pore-forming and AB-type toxins by the tailor-made compounds. In the concluding remarks, the most effective rationally designed pore-blocking antitoxins are compared with the small-molecule inhibitors of ion-selective channels of neurophysiology. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Transcranial magnetic stimulation (TMS) inhibits cortical dendrites.

    Science.gov (United States)

    Murphy, Sean C; Palmer, Lucy M; Nyffeler, Thomas; Müri, René M; Larkum, Matthew E

    2016-03-18

    One of the leading approaches to non-invasively treat a variety of brain disorders is transcranial magnetic stimulation (TMS). However, despite its clinical prevalence, very little is known about the action of TMS at the cellular level let alone what effect it might have at the subcellular level (e.g. dendrites). Here, we examine the effect of single-pulse TMS on dendritic activity in layer 5 pyramidal neurons of the somatosensory cortex using an optical fiber imaging approach. We find that TMS causes GABAB-mediated inhibition of sensory-evoked dendritic Ca(2+) activity. We conclude that TMS directly activates fibers within the upper cortical layers that leads to the activation of dendrite-targeting inhibitory neurons which in turn suppress dendritic Ca(2+) activity. This result implies a specificity of TMS at the dendritic level that could in principle be exploited for investigating these structures non-invasively.

  1. IL-1β Inhibits Human Osteoblast Migration

    Science.gov (United States)

    Hengartner, Nina-Emily; Fiedler, Jörg; Ignatius, Anita; Brenner, Rolf E

    2013-01-01

    Bone has a high capacity for self-renewal and repair. Prolonged local secretion of interleukin 1β (IL-1β), however, is known to be associated with severe bone loss and delayed fracture healing. Since induction of bone resorption by IL-1β may not sufficiently explain these pathologic processes, we investigated, in vitro, if and how IL-1β affects migration of multipotent mesenchymal stromal cells (MSC) or osteoblasts. We found that homogenous exposure to IL-1β significantly diminished both nondirectional migration and site-directed migration toward the chemotactic factors platelet-derived growth factor (PDGF)-BB and insulinlike growth factor 1 (IGF-1) in osteoblasts. Exposure to a concentration gradient of IL-1β induced an even stronger inhibition of migration and completely abolished the migratory response of osteoblasts toward PDGF-BB, IGF-1, vascular endothelial growth factor A (VEGF-A) and the complement factor C5a. IL-1β induced extracellular signal-regulated kinases 1 and 2 (ERK1/2) and c-Jun N-terminal kinases (JNK) activation and inhibition of these signaling pathways suggested an involvement in the IL-1β effects on osteoblast migration. In contrast, basal migration of MSC and their migratory activity toward PDGF-BB was found to be unaffected by IL-1β. These results indicate that the presence of IL-1β leads to impaired recruitment of osteoblasts which might influence early stages of fracture healing and could have pathological relevance for bone remodeling in inflammatory bone disease. PMID:23508571

  2. Inhibition of Quorum Sensing in Staphylococcus spp.

    Science.gov (United States)

    Brackman, Gilles; Coenye, Tom

    2015-01-01

    The Gram-positive, facultative anaerobic coccus-shaped bacteria of the genus Staphylococcus are among the most important causative agents of acute and chronic bacterial infections in humans as well as in animals. Treatment of Staphylococcus infections has become increasingly challenging due to the growing problem of antibiotic resistance. For this reason innovative antimicrobials with novel targets and modes of action are needed. Since the discovery that QS is used by Staphylococcus spp. to coordinate the expression of several genes involved in virulence, biofilm formation and pathogenicity, QS inhibition has gained increasing attention as an alternative anti-pathogenic strategy. A major advantage compared with antibiotic therapy is that QSIs are used in concentrations that do not affect bacterial growth. For this reason, it is expected that these compounds would exert less pressure towards the development of resistance. However, some important points still need to be addressed. Although several inhibitors have proven to be active antipathogenic agents in vitro and in several in vivo models, it is still unknown whether these compounds will also be useful in humans. Furthermore, several fundamental mechanisms by which the different QS systems in Staphylococcus spp. exert their regulatory functions and how they are inhibited by QSIs are still poorly understood. In order to achieve real-life applications with QSIs, these challenges should be addressed and more research will be needed. In this article, we will discuss the different QS systems present in Staphylococcus spp., how they are used to control virulence and biofilm formation and how they can be blocked.

  3. Inhibition of morphine metabolism by ketamine.

    Science.gov (United States)

    Qi, Xiaoxin; Evans, Allan M; Wang, Jiping; Miners, John O; Upton, Richard N; Milne, Robert W

    2010-05-01

    Clinical observation of a synergistic effect of ketamine on morphine analgesia remains controversial. Although a pharmacodynamic basis for an interaction has been explored in animal and clinical studies, the possibility of a pharmacokinetic mechanism has not been investigated. Whereas both morphine and morphine-6-glucuronide are effective analgesics, morphine-3-glucuronide (M3G) lacks activity. Thus, changes in the metabolism and disposition of morphine may result in an altered response. First, we investigated the interaction between morphine and ketamine in the isolated perfused rat liver preparation. The clearance of morphine was decreased from 16.8 +/- 4.6 ml/min in the control period to 7.7 +/- 2.8 ml/min in the ketamine-treatment period, with the formation clearance of M3G decreasing from 8.0 +/- 4.1 ml/min to 2.1 +/- 1.1 ml/min. Fractional conversion of morphine to M3G was significantly decreased from 0.46 +/- 0.17 in the control period to 0.28 +/- 0.14 upon the addition of ketamine. The possible mechanism of the interaction was further investigated in vitro with rat liver microsomes as the enzyme source. The formation of M3G followed single-enzyme Michaelis-Menten kinetics, with a mean apparent K(m) of 2.18 +/- 0.45 mM and V(max) of 8.67 +/- 0.59 nmol/min/mg. Ketamine inhibited morphine 3-glucuronidation noncompetitively, with a mean K(i) value of 33.3 +/- 7.9 microM. The results demonstrate that ketamine inhibits the glucuronidation of morphine in a rat model.

  4. Enoxacin Directly Inhibits Osteoclastogenesis without Inducing Apoptosis*

    Science.gov (United States)

    Toro, Edgardo J.; Zuo, Jian; Ostrov, David A.; Catalfamo, Dana; Bradaschia-Correa, Vivian; Arana-Chavez, Victor; Caridad, Aliana R.; Neubert, John K.; Wronski, Thomas J.; Wallet, Shannon M.; Holliday, L. Shannon

    2012-01-01

    Enoxacin has been identified as a small molecule inhibitor of binding between the B2-subunit of vacuolar H+-ATPase (V-ATPase) and microfilaments. It inhibits bone resorption by calcitriol-stimulated mouse marrow cultures. We hypothesized that enoxacin acts directly and specifically on osteoclasts by disrupting the interaction between plasma membrane-directed V-ATPases, which contain the osteoclast-selective a3-subunit of V-ATPase, and microfilaments. Consistent with this hypothesis, enoxacin dose-dependently reduced the number of multinuclear cells expressing tartrate-resistant acid phosphatase (TRAP) activity produced by RANK-L-stimulated osteoclast precursors. Enoxacin (50 μm) did not induce apoptosis as measured by TUNEL and caspase-3 assays. V-ATPases containing the a3-subunit, but not the “housekeeping” a1-subunit, were isolated bound to actin. Treatment with enoxacin reduced the association of V-ATPase subunits with the detergent-insoluble cytoskeleton. Quantitative PCR revealed that enoxacin triggered significant reductions in several osteoclast-selective mRNAs, but levels of various osteoclast proteins were not reduced, as determined by quantitative immunoblots, even when their mRNA levels were reduced. Immunoblots demonstrated that proteolytic processing of TRAP5b and the cytoskeletal protein l-plastin was altered in cells treated with 50 μm enoxacin. Flow cytometry revealed that enoxacin treatment favored the expression of high levels of DC-STAMP on the surface of osteoclasts. Our data show that enoxacin directly inhibits osteoclast formation without affecting cell viability by a novel mechanism that involves changes in posttranslational processing and trafficking of several proteins with known roles in osteoclast function. We propose that these effects are downstream to blocking the binding interaction between a3-containing V-ATPases and microfilaments. PMID:22474295

  5. Enoxacin directly inhibits osteoclastogenesis without inducing apoptosis.

    Science.gov (United States)

    Toro, Edgardo J; Zuo, Jian; Ostrov, David A; Catalfamo, Dana; Bradaschia-Correa, Vivian; Arana-Chavez, Victor; Caridad, Aliana R; Neubert, John K; Wronski, Thomas J; Wallet, Shannon M; Holliday, L Shannon

    2012-05-18

    Enoxacin has been identified as a small molecule inhibitor of binding between the B2-subunit of vacuolar H+-ATPase (V-ATPase) and microfilaments. It inhibits bone resorption by calcitriol-stimulated mouse marrow cultures. We hypothesized that enoxacin acts directly and specifically on osteoclasts by disrupting the interaction between plasma membrane-directed V-ATPases, which contain the osteoclast-selective a3-subunit of V-ATPase, and microfilaments. Consistent with this hypothesis, enoxacin dose-dependently reduced the number of multinuclear cells expressing tartrate-resistant acid phosphatase (TRAP) activity produced by RANK-L-stimulated osteoclast precursors. Enoxacin (50 μM) did not induce apoptosis as measured by TUNEL and caspase-3 assays. V-ATPases containing the a3-subunit, but not the "housekeeping" a1-subunit, were isolated bound to actin. Treatment with enoxacin reduced the association of V-ATPase subunits with the detergent-insoluble cytoskeleton. Quantitative PCR revealed that enoxacin triggered significant reductions in several osteoclast-selective mRNAs, but levels of various osteoclast proteins were not reduced, as determined by quantitative immunoblots, even when their mRNA levels were reduced. Immunoblots demonstrated that proteolytic processing of TRAP5b and the cytoskeletal protein L-plastin was altered in cells treated with 50 μM enoxacin. Flow cytometry revealed that enoxacin treatment favored the expression of high levels of DC-STAMP on the surface of osteoclasts. Our data show that enoxacin directly inhibits osteoclast formation without affecting cell viability by a novel mechanism that involves changes in posttranslational processing and trafficking of several proteins with known roles in osteoclast function. We propose that these effects are downstream to blocking the binding interaction between a3-containing V-ATPases and microfilaments.

  6. Cartilage proteoglycans inhibit fibronectin-mediated adhesion

    Science.gov (United States)

    Rich, A. M.; Pearlstein, E.; Weissmann, G.; Hoffstein, S. T.

    1981-09-01

    Normal tissues and organs show, on histological examination, a pattern of cellular and acellular zones that is characteristic and unique for each organ or tissue. This pattern is maintained in health but is sometimes destroyed by disease. For example, in mobile joints, the articular surfaces consist of relatively acellular hyaline cartilage, and the joint space is enclosed by a capsule of loose connective tissue with a lining of fibroblasts and macrophages. In the normal joint these cells are confined to the synovial lining and the articular surface remains acellular. In in vitro culture, macrophages and their precursor monocytes are very adhesive, and fibroblasts can migrate and overgrow surfaces such as collagen or plastic used for tissue culture. The fibroblasts adhere to collagen by means of fibronectin, which they synthesize and secrete1. Because the collagen of cartilage is capable of binding serum fibronectin2 and fibronectin is present in cartilage during its development3, these cells should, in theory, slowly migrate from the synovial lining to the articular surface. It is their absence from the articular cartilage in normal circumstances, and then presence in such pathological states as rheumatoid arthritis, that is striking. We therefore set out to determine whether a component of cartilage could prevent fibroblast adherence in a defined adhesion assay. As normal cartilage is composed of 50% proteoglycans and 50% collagen by dry weight4, we tested the possibility that the proteoglycans in cartilage inhibit fibroblast adhesion to collagen. We present here evidence that fibroblast spreading and adhesion to collagenous substrates is inhibited by cartilage proteoglycans.

  7. Reconciling the role of serotonin in behavioral inhibition and aversion: acute tryptophan depletion abolishes punishment-induced inhibition in humans.

    Science.gov (United States)

    Crockett, Molly J; Clark, Luke; Robbins, Trevor W

    2009-09-23

    The neuromodulator serotonin has been implicated in a large number of affective and executive functions, but its precise contribution to motivation remains unclear. One influential hypothesis has implicated serotonin in aversive processing; another has proposed a more general role for serotonin in behavioral inhibition. Because behavioral inhibition is a prepotent reaction to aversive outcomes, it has been a challenge to reconcile these two accounts. Here, we show that serotonin is critical for punishment-induced inhibition but not overall motor response inhibition or reporting aversive outcomes. We used acute tryptophan depletion to temporarily lower brain serotonin in healthy human volunteers as they completed a novel task designed to obtain separate measures of motor response inhibition, punishment-induced inhibition, and sensitivity to aversive outcomes. After a placebo treatment, participants were slower to respond under punishment conditions compared with reward conditions. Tryptophan depletion abolished this punishment-induced inhibition without affecting overall motor response inhibition or the ability to adjust response bias in line with punishment contingencies. The magnitude of reduction in punishment-induced inhibition depended on the degree to which tryptophan depletion reduced plasma tryptophan levels. These findings extend and clarify previous research on the role of serotonin in aversive processing and behavioral inhibition and fit with current theorizing on the involvement of serotonin in predicting aversive outcomes.

  8. Firing regulation of fast-spiking interneurons by autaptic inhibition

    Science.gov (United States)

    Guo, Daqing; Chen, Mingming; Perc, Matjaž; Wu, Shengdun; Xia, Chuan; Zhang, Yangsong; Xu, Peng; Xia, Yang; Yao, Dezhong

    2016-05-01

    Fast-spiking (FS) interneurons in the brain are self-innervated by powerful inhibitory GABAergic autaptic connections. By computational modelling, we investigate how autaptic inhibition regulates the firing response of such interneurons. Our results indicate that autaptic inhibition both boosts the current threshold for action potential generation and modulates the input-output gain of FS interneurons. The autaptic transmission delay is identified as a key parameter that controls the firing patterns and determines multistability regions of FS interneurons. Furthermore, we observe that neuronal noise influences the firing regulation of FS interneurons by autaptic inhibition and extends their dynamic range for encoding inputs. Importantly, autaptic inhibition modulates noise-induced irregular firing of FS interneurons, such that coherent firing appears at an optimal autaptic inhibition level. Our results reveal the functional roles of autaptic inhibition in taming the firing dynamics of FS interneurons.

  9. Btk inhibition treats TLR7/IFN driven murine lupus.

    Science.gov (United States)

    Bender, Andrew T; Pereira, Albertina; Fu, Kai; Samy, Eileen; Wu, Yin; Liu-Bujalski, Lesley; Caldwell, Richard; Chen, Yi-Ying; Tian, Hui; Morandi, Federica; Head, Jared; Koehler, Ursula; Genest, Melinda; Okitsu, Shinji L; Xu, Daigen; Grenningloh, Roland

    2016-03-01

    Bruton's tyrosine kinase (Btk) is expressed in a variety of immune cells and previous work has demonstrated that blocking Btk is a promising strategy for treating autoimmune diseases. Herein, we utilized a tool Btk inhibitor, M7583, to determine the therapeutic efficacy of Btk inhibition in two mouse lupus models driven by TLR7 activation and type I interferon. In BXSB-Yaa lupus mice, Btk inhibition reduced autoantibodies, nephritis, and mortality. In the pristane-induced DBA/1 lupus model, Btk inhibition suppressed arthritis, but autoantibodies and the IFN gene signature were not significantly affected; suggesting efficacy was mediated through inhibition of Fc receptors. In vitro studies using primary human macrophages revealed that Btk inhibition can block activation by immune complexes and TLR7 which contributes to tissue damage in SLE. Overall, our results provide translational insight into how Btk inhibition may provide benefit to a variety of SLE patients by affecting both BCR and FcR signaling.

  10. Latent inhibition and autonomic responses: a psychophysiological approach.

    Science.gov (United States)

    Vaitl, D; Lipp, O V

    1997-10-01

    Latent inhibition, retarded learning after preexposure to the to-be-conditioned stimulus, has been implied as a tool for the investigation of attentional deficits in schizophrenia and related disorders. The present paper reviews research that used Pavlovian conditioning as indexed by autonomic responses (electrodermal, vasomotor, cardiac) to investigate latent inhibition in adult humans. Latent inhibition has been demonstrated repeatedly in healthy subjects in absence of a masking task that is required in other latent inhibition paradigms. Moreover, latent inhibition of Pavlovian conditioning is stimulus-specific and increases with an increased number of preexposure trials which mirrors results from research in animals. A reduction of latent inhibition has been shown in healthy subjects who score high on questionnaire measures of psychosis proneness and in unmedicated schizophrenic patients. The latter result was obtained in a within-subject paradigm that holds promise for research with patient samples.

  11. Molecular mechanisms of DNA repair inhibition by caffeine

    Energy Technology Data Exchange (ETDEWEB)

    Selby, C.P.; Sancar, A. (Univ. of North Carolina School of Medicine, Chapel Hill (USA))

    1990-05-01

    Caffeine potentiates the mutagenic and lethal effects of genotoxic agents. It is thought that this is due, at least in some organisms, to inhibition of DNA repair. However, direct evidence for inhibition of repair enzymes has been lacking. Using purified Escherichia coli DNA photolyase and (A)BC excinuclease, we show that the drug inhibits photoreactivation and nucleotide excision repair by two different mechanisms. Caffeine inhibits photoreactivation by interfering with the specific binding of photolyase to damaged DNA, and it inhibits nucleotide excision repair by promoting nonspecific binding of the damage-recognition subunit, UvrA, of (A)BC excinuclease. A number of other intercalators, including acriflavin and ethidium bromide, appear to inhibit the excinuclease by a similar mechanism--that is, by trapping the UvrA subunit in nonproductive complexes on undamaged DNA.

  12. [Inhibition of aromatics on ammonia-oxidizing activity of sediment].

    Science.gov (United States)

    Dong, Chun-hong; Hu, Hong-ying; Wei, Dong-bin; Huang, Xia; Qian, Yi

    2004-03-01

    The inhibition of 24 aromatics on ammonia-oxidizing activity of nitrifying bacteria in sediment was measured. The effects of the kind, number and position of substituted groups on ammonia-oxidizing activity of nitrifying bacteria were discussed. The inhibition of mono-substituted benzenes on ammonia-oxidizing activity of nitrifying bacteria were in order of -OH > -NO2 > -NH2 > -Cl > -CH3 > -H. The position of substituted groups of di-substituted benzenes also affected the inhibition, and the inhibitions of dimethylbenzenes(xylene) were in order of meta-> ortho-> para-. The increase in number of substituted group on benzene-ring enhanced the inhibition of aromatics studied in this study on nitrifying bacteria. There was a linear relationship between inhibition (IC50, mumol.L-1) of aromatics on ammonia-oxidizing activity and total electronegativity (sigma E) of aromatics: lgIC50 = 14.72 - 0.91 sigma E.

  13. Study on the Inhibition of Fermented Soybean to Cancer Cells

    Institute of Scientific and Technical Information of China (English)

    LU Yan; WANG Wei; SHAN Yi; E Zhiqiang; WANG Liqun

    2009-01-01

    In the experiment, the inhibition of isoflavones extracted from soybean and tempe to SP2/0 and Hela cells was studied,and the inhibition rate of each unit for cancer cells was also studied. The results showed that the inhibition rate of tempe isoflavones to SP2/0 was 96.9% and to Hela cells was 69.5% when the concentration was 20 μg·mL-1. In the same condition, the inhibition rate of soybean isoflavones was 83.16% and 60.5%. With the decline of concentration, the inhibition rate decreased. The inhibition of isoflavones to SP2/0 did not exist when the concentration was 5-1.25 μg·mL-1.

  14. Inhibition of Action, Thought, and Emotion: A Selective Neurobiological Review

    OpenAIRE

    Dillon, Daniel; Pizzagalli, Diego

    2007-01-01

    The neural bases of inhibitory function are reviewed, covering data from paradigms assessing inhibition of motor responses (antisaccade, go/nogo, stop-signal), cognitive sets (e.g., Wisconsin Card Sort Test), and emotion (fear extinction). The frontal cortex supports performance on these paradigms, but the specific neural circuitry varies: response inhibition depends upon fronto-basal ganglia networks, inhibition of cognitive sets is supported by orbitofrontal cortex, and retention of fear ex...

  15. Inhibition of poliovirus RNA synthesis by brefeldin A.

    OpenAIRE

    Maynell, L A; Kirkegaard, K; Klymkowsky, M W

    1992-01-01

    Brefeldin A (BFA), a fungal metabolite that blocks transport of newly synthesized proteins from the endoplasmic reticulum, was found to inhibit poliovirus replication 10(5)- to 10(6)-fold. BFA does not inhibit entry of poliovirus into the cell or translation of viral RNA. Poliovirus RNA synthesis, however, is completely inhibited by BFA. A specific class of membranous vesicles, with which the poliovirus replication complex is physically associated, is known to proliferate in poliovirus-infect...

  16. Acute inhibition of corticosteroidogenesis by inhibitors of calmodulin action.

    Science.gov (United States)

    Carsia, R V; Moyle, W R; Wolff, D J; Malamed, S

    1982-11-01

    To identify the possible role of calmodulin in ACTH function, we tested the ability of chlorpromazine (CP) and other calmodulin antagonists to inhibit steroidogenesis of isolated adrenocortical cells of the rat. CP reversibly inhibited maximal ACTH-induced corticosterone (B) production. The presence of the drug did not alter the ED50 of ACTH stimulation (3.2 X 10(3) pg/ml), suggesting that it inhibited ACTH-induced steroidogenesis in a noncompetitive manner. The CP concentration required for half-maximal inhibition was 8.2 microM, a value close to the dissociation constant of the CP-calmodulin complex (5.3 microM). Concentrations greater than 40 microM resulted in complete inhibition. Similar concentrations of CP inhibited ACTH-induced cAMP accumulation in a dose-dependent manner, indicating an effect of the drug on early events in ACTH action. In addition, CP also apparently acted at a site distal to the point of cAMP formation, as shown by the finding that it inhibited cAMP-induced B production. CP inhibition of ACTH-induced B production was independent of the Ca2+ concentration, suggesting that the drug did not compete with Ca2+ directly. Concentrations of CP greater than 20 microM inhibited protein synthesis as measured by leucine incorporation into cellular proteins. Thus, although the inhibitory effect of high concentrations of CP on steroidogenesis might be explained by an effect on protein synthesis, the inhibition seen at 10 microM appeared to be independent of protein synthesis. Other antagonists of calmodulin action inhibited maximal ACTH-induced B production with the following relative potencies: trifluoperazine greater than CP greater than haloperidol greater than chlordiazepoxide. This order is similar to that reported for inhibition of calmodulin-activated phosphodiesterase and for binding to calmodulin. These findings suggest that calmodulin may modulate the effect of ACTH on steroidogenesis at multiple sites.

  17. High molecular weight polysaccharide that binds and inhibits virus

    Science.gov (United States)

    Konowalchuk, Thomas W

    2014-01-14

    This invention provides a high molecular weight polysaccharide capable of binding to and inhibiting virus and related pharmaceutical formulations and methods on inhibiting viral infectivity and/or pathogenicity, as well as immunogenic compositions. The invention further methods of inhibiting the growth of cancer cells and of ameliorating a symptom of aging. Additionally, the invention provides methods of detecting and/or quantifying and/or isolating viruses.

  18. Inhibition of human aromatase complex (CYP19) by antiepileptic drugs

    DEFF Research Database (Denmark)

    Jacobsen, Naja Wessel; Halling-Sørensen, Bent; Birkved, Franziska Maria A Kramer

    2008-01-01

    transfected insect cells using dibenzylfluorescein as substrate. The drugs inhibiting CYP19 were: lamotrigine, oxcarbazepine, tiagabine, phenobarbital, phenytoin, ethosuximide, and valproate. The inhibitory effects (50% reduction in activity compared to enzymes without inhibitor present) were in the range...... with valproate and phenobarbital. When adding carbamazepine to a range of valproate concentrations no additional inhibition was seen. The data for some of the AEDs show that side effects on steroid synthesis in humans due to inhibition of aromatase should be considered....

  19. Are individual differences in arithmetic fact retrieval related to inhibition?

    OpenAIRE

    Bellon, Elien

    2016-01-01

    Although it has been proposed that inhibition is related to individual differences in mathematical achievement, it is not clear how it is related to specific aspects of mathematical skills, such as arithmetic fact retrieval. The present study therefore investigated the association between inhibition and arithmetic fact retrieval and further examined the unique role of inhibition in individual differences in arithmetic fact retrieval, in addition to numerical magnitude processin...

  20. High molecular weight polysaccharide that binds and inhibits virus

    Energy Technology Data Exchange (ETDEWEB)

    Konowalchuk, Thomas W.; Konowalchuk, Jack

    2017-07-18

    This invention provides a high molecular weight polysaccharide capable of binding to and inhibiting virus and related pharmaceutical formulations and methods of inhibiting viral infectivity and/or pathogenicity, as well as immunogenic compositions. The invention further includes methods of inhibiting the growth of cancer cells and of ameliorating a symptom of aging. Additionally, the invention provides methods of detecting and/or quantifying and/or isolating viruses.

  1. Functional networks underlying latent inhibition learning in the mouse brain

    OpenAIRE

    Puga, Frank; Barrett, Douglas W.; Bastida, Christel C.; Gonzalez-Lima, F.

    2007-01-01

    The present study reports the first comprehensive map of brain networks underlying latent inhibition learning and the first application of structural equation modeling to cytochrome oxidase data. In latent inhibition, repeated exposure to a stimulus results in a latent form of learning that inhibits subsequent associations with that stimulus. As neuronal energy demand to form learned associations changes, so does the induction of the respiratory enzyme cytochrome oxidase. Therefore, cytochrom...

  2. Protection from Latent Inhibition Provided by a Conditioned Inhibitor

    OpenAIRE

    McConnell, Bridget L.; Wheeler, Daniel S.; Urcelay, Gonzalo P; Miller, Ralph R.

    2009-01-01

    Two conditioned suppression experiments with rats investigated the influence on latent inhibition of compounding a Pavlovian conditioned inhibitor with the target cue during preexposure treatment. Results were compared to subjects that received conventional latent inhibition training, no preexposure, or preexposure to the target cue in compound with a neutral stimulus. In Experiment 1, greater attenuation of the latent inhibition effect was observed in subjects that received target preexposur...

  3. A small yeast RNA inhibits HCV IRES mediated translation and inhibits replication of poliovirus in vivo

    Institute of Scientific and Technical Information of China (English)

    Xue-Song Liang; Jian-Qi Lian; Yong-Xing Zhou; Qing-He Nie; Chun-Qiu Hao

    2003-01-01

    AIM: To investigate the anti-virus infection activity of internal ribosome entry site (IRES) specific inhibitor RNA (IRNA).METHODS: IRNA eukaryotic vector pcRz-IRNA or mIRNA eukaryotic vector pcRz-mIRNA was tansfected into human hepatocarcinoma cells (HHCC), then selected with neomycin G418 for 4 to 8 weeks, and then infected with polio virus vaccinas line. The cytopethogenesis effect was investigated and the cell extract was collected. At last the polio virus titer of different cells was determined by plaque assay.RESULTS: Constitutive expression of IRNA was not detrimental to cell growth. HCV IRES-mediated capindependent translation was markedly inhibited in cells constitutively expressing IRNA compared to control hepatoma cells. However, cap-dependent translation was not significantly affected in these cell line. Additionally, HHCC cells constitutively expressing IRNA became refractory to infection of polio virus.CONCLUSION: IRES specific IRNA can inhibit HCV IRES mediated translation and poliovirus replication.

  4. Schedule of Punishment and Inhibition of Aggression in Children

    Science.gov (United States)

    Parke, Ross D.; Deur, Jan L.

    1972-01-01

    Data showed that consistent punishment resulted in faster inhibition than inconsistent punishment; subjects who were punished showed less persistence than subjects placed on an extinction schedule. (Authors)

  5. Selective and nonselective inhibition of competitors in picture naming.

    Science.gov (United States)

    Shao, Zeshu; Meyer, Antje S; Roelofs, Ardi

    2013-11-01

    The present study examined the relation between nonselective inhibition and selective inhibition in picture naming performance. Nonselective inhibition refers to the ability to suppress any unwanted response, whereas selective inhibition refers to the ability to suppress specific competing responses. The degree of competition in picture naming was manipulated by presenting targets along with distractor words that could be semantically related (e.g., a picture of a dog combined with the word cat) or unrelated (tree) to the picture name. The mean naming response time (RT) was longer in the related than in the unrelated condition, reflecting semantic interference. Delta plot analyses showed that participants with small mean semantic interference effects employed selective inhibition more effectively than did participants with larger semantic interference effects. The participants were also tested on the stop-signal task, which taps nonselective inhibition. Their performance on this task was correlated with their mean naming RT but, importantly, not with the selective inhibition indexed by the delta plot analyses and the magnitude of the semantic interference effect. These results indicate that nonselective inhibition ability and selective inhibition of competitors in picture naming are separable to some extent.

  6. Inhibition behavior for copper corrosion by photoelectrochemical methods

    Institute of Scientific and Technical Information of China (English)

    徐群杰; 周国定

    2003-01-01

    The application of photoelectrochemical methods in the inhibition effects for copper corrosion was described. The methods include cyclic voltammetry photocurrent measurements, intensity modulated photocurrent spectrum(IMPS) and laser-scanning photoelectrochemical microscopic method(PEM) which have been applied to the evaluation of inhibitors and inhibition behavior. The inhibition effect of BTA for copper corrosion is better than that of 4CBTA, 5CBTA, CBT-1, PTD, BT-250, CBTME and CBTBE at the same concentration. The inhibition mechanism of the derivatives of BTA with-COOH group(4CBTA, 5CBTA, CBT-1) is different from those with estergroup(CBTME, CBTBE).

  7. Osmotic stress inhibits thymidine incorporation into soybean protoplast DNA.

    Science.gov (United States)

    Cress, D E

    1982-10-01

    DNA synthesis in protoplasts isolated from soybean cell suspension cultures has been investigated by [(3)H] thymidine uptake and incorporation kinetics. Initial rates of incorporation in exponential and 5-fluorodeoxyuridine synchronized protoplasts are inhibited by increased osmolarities of the medium. The inhibition was not readily reversible during 3 h culture in low osmotic medium. Velocity sedimentation analyses of replicating DNA from such protoplasts shows a complex pattern of inhibition. The inhibition probably effects replicon initiation as well as strand elongation and ligation of replication intermediates.

  8. Glyphosate and AMPA inhibit cancer cell growth through inhibiting intracellular glycine synthesis

    Directory of Open Access Journals (Sweden)

    Li Q

    2013-07-01

    Full Text Available Qingli Li,1,2 Mark J Lambrechts,1 Qiuyang Zhang,1 Sen Liu,1 Dongxia Ge,1 Rutie Yin,2 Mingrong Xi,2 Zongbing You1 1Departments of Structural and Cellular Biology and Orthopaedic Surgery, Tulane Cancer Center and Louisiana Cancer Research Consortium, Tulane Center for Stem Cell Research and Regenerative Medicine, and Tulane Center for Aging, Tulane University Health Sciences Center, New Orleans, LA, USA; 2Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, People’s Republic of China Abstract: Glycine is a nonessential amino acid that is reversibly converted from serine intracellularly by serine hydroxymethyltransferase. Glyphosate and its degradation product, aminomethylphosphonic acid (AMPA, are analogs to glycine, thus they may inhibit serine hydroxymethyltransferase to decrease intracellular glycine synthesis. In this study, we found that glyphosate and AMPA inhibited cell growth in eight human cancer cell lines but not in two immortalized human normal prostatic epithelial cell lines. AMPA arrested C4-2B and PC-3 cancer cells in the G1/G0 phase and inhibited entry into the S phase of the cell cycle. AMPA also promoted apoptosis in C4-2B and PC-3 cancer cell lines. AMPA upregulated p53 and p21 protein levels as well as procaspase 9 protein levels in C4-2B cells, whereas it downregulated cyclin D3 protein levels. AMPA also activated caspase 3 and induced cleavage of poly (adenosine diphosphate [ADP]-ribose polymerase. This study provides the first evidence that glyphosate and AMPA can inhibit proliferation and promote apoptosis of cancer cells but not normal cells, suggesting that they have potentials to be developed into a new anticancer therapy. Keywords: serine hydroxymethyltransferase, prostate cancer, apoptosis

  9. Nifuroxazide inhibits survival of multiple myeloma cells by directly inhibiting STAT3

    OpenAIRE

    2008-01-01

    Constitutive activation of the transcription factor STAT3 contributes to the pathogenesis of many cancers, including multiple myeloma (MM). Since STAT3 is dispensable in most normal tissue, targeted inhibition of STAT3 is an attractive therapy for patients with these cancers. To identify STAT3 inhibitors, we developed a transcriptionally based assay and screened a library of compounds known to be safe in humans. We found the drug nifuroxazide to be an effective inhibitor of STAT3 function. Ni...

  10. Sclareol isolated from Salvia officinalis improves facial wrinkles via an antiphotoaging mechanism.

    Science.gov (United States)

    Park, Ji-Eun; Lee, Kyung-Eun; Jung, Eunsun; Kang, Seunghyun; Kim, Youn Joon

    2016-12-01

    Ultraviolet (UV) irradiation triggers skin photoaging processes, which disrupt the normal three-dimensional integrity of skin. UV-induced oxidative stress, both directly and indirectly, stimulates complex signaling pathways. UV radiation activates skin cell surface receptors on a molecular level and triggers severe changes in extracellular matrix (ECM) proteins, resulting in skin photoaging. Sclareol isolated from Salvia officinalis is widely used as a fragrance material. Sclareol is known to exert various biological activities, but its antiphotoaging effect has not been elucidated to date. Therefore, we evaluated wrinkle improvement efficacy of sclareol. Human dermal fibroblast cell line (Hs68) and a reconstructed human epidermis (RHE) model were used to evaluate the antiphotoaging effect of sclareol in vitro. A clinical study treated with 0.02% sclareol-containing cream was conducted to identify the ability of sclareol to improve wrinkles. First, sclareol enhanced cellular proliferation and blocked UVB-induced cell death. Sclareol inhibited the UVB-induced mRNA expression of matrix metalloproteinases (MMPs) by regulating the protein expression of AP-1 constituents. In RHE model, sclareol recovered the UVB-induced decrease in epidermal thickness and the expression of proliferating cell nuclear antigen (PCNA). In clinical trial, visually assessed changes and several wrinkle parameters were considered to be statistically different between the test and control groups at 12 weeks. In this study, sclareol inhibited various photoaging phenomena in human fibroblasts and RHE model. In addition, sclareol-containing cream improved wrinkles in a clinical trial. Taken together, sclareol alleviates facial wrinkle formation via an antiphotoaging mechanism and may be an effective candidate ingredient. © 2016 Wiley Periodicals, Inc.

  11. Photoprotective Potential of Glycolic Acid by Reducing NLRC4 and AIM2 Inflammasome Complex Proteins in UVB Radiation-Induced Normal Human Epidermal Keratinocytes and Mice.

    Science.gov (United States)

    Hung, Sung-Jen; Tang, Sheau-Chung; Liao, Pei-Yun; Ge, Jheng-Siang; Hsiao, Yu-Ping; Yang, Jen-Hung

    2017-02-01

    Exposure to UVB radiation induces inflammation and free radical-mediated oxidative stress through reactive oxygen species (ROS) that play a crucial role in the induction of skin cancer. Glycolic acid (GA) is frequently used in cosmetics and dermatology. The aim of the study was to analyze the photoprotective mechanisms through which GA retards UVB-induced ROS accumulation and inflammation in normal human epidermal keratinocytes (NHEKs) and mice skin, respectively. NHEK cell line and C57BL/6J mice were treated with GA (0.1 or 5 mM) for 24 h followed by UVB irradiation. ROS accumulation, DNA damage, and expression of inflammasome complexes (NLRP3, NLRC4, ASC, and AIM2) were measured in vitro. Epidermal thickness and inflammasome complex proteins were analyzed in vivo. GA significantly prevented UVB-induced loss of skin cell viability, ROS formation, and DNA damage (single and double strands DNA break). GA suppressed the mRNA expression levels of NLRC4 and AIM2 among the inflammasome complexes. GA also blocked interleukin (IL)-1β by reducing the activity of caspase-1 in the NHEKs. Treatment with GA (2%) inhibited UVB-induced inflammation marker NLRC4 protein levels in mouse dorsal skin. The photoprotective activity of GA was ascribed to the inhibition of ROS formation and DNA damage, as well as a reduction in the activities of inflammasome complexes and IL-1β. We propose that GA has anti-inflammatory and photoprotective effects against UVB irradiation. GA is potentially beneficial to the protection of human skin from UV damage.

  12. Protective Effect of Garlic on Cellular Senescence in UVB-Exposed HaCaT Human Keratinocytes.

    Science.gov (United States)

    Kim, Hye Kyung

    2016-07-29

    Ultraviolet (UV) irradiation generates reactive oxygen species (ROS) in the cells, which induces the cellular senescence and photoaging. The present study investigated the protective effects of garlic on photo-damage and cellular senescence in UVB-exposed human keratinocytes, HaCaT cells. An in vitro cell free system was used to examine the scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals and nitric oxide (NO). The effect of garlic extract on ROS formation, MMP-1 protein and mRNA expressions, cytokines such as interleukin (IL)-1β and IL-6, senescence associated-β-galactosidase (SA-β-gal) activity, and silent information regulator T1 (SIRT1) activity were determined in UVB-irradiated HaCaT cells. Garlic exhibited strong DPPH radical and NO scavenging activity in cell free system exhibiting IC50 values of 2.50 mg/mL and 4.38 mg/mL, respectively. Garlic pretreatment attenuated the production of UVB-induced intracellular ROS. MMP-1 level, which has been known to be induced by ROS, was dramatically elevated by UVB irradiation, and UVB-induced MMP-1 mRNA and protein expressions were significantly reduced by garlic treatment (50 µg/mL) comparable to those of UV-unexposed control cells. UV-induced pro-inflammatory cytokine productions (IL-6 and IL-1β) were significantly inhibited by pretreatment with garlic in a dose-dependent manner. SA-β-gal activity, a classical biomarker of cellular senescence, and SIRT1 activity, which has attracted attention as an anti-aging factor in recent years, were ameliorated by garlic treatment in UV-irradiated HaCaT cells. The present study provides the first evidence of garlic inhibiting UVB-induced photoaging as a result of augmentation of cellular senescence in HaCaT human keratinocytes.

  13. α-Santalol, a skin cancer chemopreventive agent with potential to target various pathways involved in photocarcinogenesis.

    Science.gov (United States)

    Santha, Sreevidya; Dwivedi, Chandradhar

    2013-01-01

    This study is designed to investigate the chemopreventive effect and molecular mechanisms of α-santalol on UVB-induced skin tumor development in SKH-1 hairless mouse, a widely used model for human photocarcinogenesis. A dose of UVB radiation (30 mJ cm(-2) day(-1)) that is in the range of human sunlight exposure was used for the initiation and promotion of tumor. Topical treatment of mice with α-santalol (10%, wt/vol in acetone) caused reduction in tumor incidence, multiplicity and volume. In our study, the anticarcinogenic action of α-santalol against UVB-induced photocarcinogenesis was found to be associated with inhibition of inflammation and epidermal cell proliferation, cell cycle arrest and induction of apoptosis. α-Santalol pretreatment strongly inhibited UVB-induced epidermal hyperplasia and thickness of the epidermis, expression of proliferation and inflammation markers proliferating cell nuclear antigen (PCNA), Ki-67 and cyclooxygenase 2 (Cox-2). Significant decrease in the expression of cyclins A, B1, D1 and D2 and cyclin-dependent kinases (Cdk)s Cdk1 (Cdc2), Cdk2, Cdk4 and Cdk6 and an upregulated expression of cyclin-dependent kinase (CDK) inhibitor Cip1/p21 were found in α-santalol pretreated group. Furthermore, an elevated level of cleaved caspase 3 and cleaved poly (ADP-ribose) polymerase (PARP) were observed in α-santalol-treated group. Our data suggested that α-santalol is a safer and promising skin cancer chemopreventive agent with potential to target various pathways involved in photocarcinogenesis.

  14. Pirfenidone inhibits post-traumatic proliferative vitreoretinopathy.

    Science.gov (United States)

    Khanum, B N M K; Guha, R; Sur, V P; Nandi, S; Basak, S K; Konar, A; Hazra, S

    2017-03-17

    PurposeThe purpose of the study was to evaluate the efficacy and safety of intravitreal pirfenidone for inhibition of proliferative vitreoretinopathy (PVR) in a model of penetrating ocular injury.Patients and methodsPenetrating trauma was induced on the retina of rabbit and treated either with 0.1 ml of phosphate-buffered saline (PBS) or 0.1 ml of 0.5% pirfenidone, and development of PVR was evaluated clinically and graded after 1 month. Histopathology and immunohistochemistry with transforming growth factor beta (TGFβ), alpha smooth muscle actin (αSMA), and collagen-1 were performed to assess the fibrotic changes. Expression of cytokines in the vitro-retinal tissues at different time points following pirfenidone and PBS injection was examined by RT-PCR. Availability of pirfenidone in the vitreous of rabbit at various time points was determined by high-performance liquid chromatography following injection of 0.1 ml of 0.5% pirfenidone. In normal rabbit eye, 0.1 ml of 0.5% pirfenidone was injected to evaluate any toxic effect.ResultsClinical assessment and grading revealed prevention of PVR formation in pirfenidone-treated animals, gross histology, and histopathology confirmed the observation. Immunohistochemistry showed prevention in the expression of collagen-I, αSMA, and TGFβ in the pirfenidone-treated eyes compared to the PBS-treated eyes. Pirfenidone inhibited increased gene expression of cytokines observed in control eyes. Pirfenidone could be detected up to 48 h in the vitreous of rabbit eye following single intravitreal injection. Pirfenidone did not show any adverse effect following intravitreal injection; eyes were devoid of any abnormal clinical sign, intraocular pressure, and electroretinography did not show any significant change and histology of retina remained unchanged.ConclusionThis animal study shows that pirfenidone might be a potential therapy for PVR. Further clinical study will be useful to evaluate the clinical application of

  15. Inhibition of autophagy induced by proteasome inhibition increases cell death in human SHG-44 glioma cells

    Institute of Scientific and Technical Information of China (English)

    Peng-fei GE; Ji-zhou ZHANG; Xiao-fei WANG; Fan-kai MENG; Wen-chen LI; Yong-xin LUAN; Feng LING; Yi-nan LUO

    2009-01-01

    Aim:The ubiquitin-proteasome system (UPS) and lysosome-dependent macroautophagy (autophagy) are two major intracellular pathways for protein degradation.Recent studies suggest that proteasome inhibitors may reduce tumor growth and activate autophagy.Due to the dual roles of autophagy in tumor cell survival and death,the effect of autophagy on the destiny of glioma cells remains unclear.In this study,we sought to investigate whether inhibition of the proteasome can induce autophagy and the effects of autophagy on the fate of human SHG-44 glioma cells.Methods:The proteasome inhibitor MG-132 was used to induce autophagy in SHG-44 glioma cells,and the effect of autophagy on the survival of SHG-44 glioma cells was investigated using an autophagy inhibitor 3-MA.Cell viability was measured by MTT assay.Apoptosis and cell cycle were detected by flow cytometry.The expression of autophagy related proteins was determined by Western blot.Results:MG-132 inhibited cell proliferation,induced cell death and cell cycle arrest at G~JM phase,and activated autophagy in SHG-44 glioma cells.The expression of autophagy-related Beclin-1 and LC3-1 was significantly up-regulated and part of LC3-1 was converted into LC3-11.However,when SHG-44 glioma cells were co-treated with MG-132 and 3-MA,the cells became less viable,but cell death and cell numbers at G2/M phase increased.Moreover,the accumulation of acidic vesicular organelles was decreased,the expression of Beclin-1 and LC3 was significantly down-regulated and the conversion of LC3-11 from LC3-1 was also inhibited.Conclusion:Inhibition of the proteasome can induce autophagy in human SHG-44 glioma cells,and inhibition of autophagy increases cell death.This discovery may shed new light on the effect of autophagy on modulating the fate of SHG-44 glioma cells.

  16. Pharmacologic inhibition of lactate production prevents myofibroblast differentiation.

    Science.gov (United States)

    Kottmann, Robert Matthew; Trawick, Emma; Judge, Jennifer L; Wahl, Lindsay A; Epa, Amali P; Owens, Kristina M; Thatcher, Thomas H; Phipps, Richard P; Sime, Patricia J

    2015-12-01

    Myofibroblasts are one of the primary cell types responsible for the accumulation of extracellular matrix in fibrosing diseases, and targeting myofibroblast differentiation is an important therapeutic strategy for the treatment of pulmonary fibrosis. Transforming growth factor-β (TGF-β) has been shown to be an important inducer of myofibroblast differentiation. We previously demonstrated that lactate dehydrogenase and its metabolic product lactic acid are important mediators of myofibroblast differentiation, via acid-induced activation of latent TGF-β. Here we explore whether pharmacologic inhibition of LDH activity can prevent TGF-β-induced myofibroblast differentiation. Primary human lung fibroblasts from healthy patients and those with pulmonary fibrosis were treated with TGF-β and or gossypol, an LDH inhibitor. Protein and RNA were analyzed for markers of myofibroblast differentiation and extracellular matrix generation. Gossypol inhibited TGF-β-induced expression of the myofibroblast marker α-smooth muscle actin (α-SMA) in a dose-dependent manner in both healthy and fibrotic human lung fibroblasts. Gossypol also inhibited expression of collagen 1, collagen 3, and fibronectin. Gossypol inhibited LDH activity, the generation of extracellular lactic acid, and the rate of extracellular acidification in a dose-dependent manner. Furthermore, gossypol inhibited TGF-β bioactivity in a dose-dependent manner. Concurrent treatment with an LDH siRNA increased the ability of gossypol to inhibit TGF-β-induced myofibroblast differentiation. Gossypol inhibits TGF-β-induced myofibroblast differentiation through inhibition of LDH, inhibition of extracellular accumulation of lactic acid, and inhibition of TGF-β bioactivity. These data support the hypothesis that pharmacologic inhibition of LDH may play an important role in the treatment of pulmonary fibrosis.

  17. The grapevine polygalacturonase-inhibiting protein (VvPGIP1) reduces Botrytis cinerea susceptibility in transgenic tobacco and differentially inhibits fungal polygalacturonases

    NARCIS (Netherlands)

    Joubert, D.A.; Slaughter, A.R.; Kemp, G.; Becker, J.V.W.; Krooshof, G.H.; Bergmann, C.; Benen, J.A.E.; Pretorius, I.S.; Vivier, M.A.

    2006-01-01

    Polygalacturonase-inhibiting proteins (PGIPs) selectively inhibit polygalacturonases (PGs) secreted by invading plant pathogenic fungi. PGIPs display differential inhibition towards PGs from different fungi, also towards different isoforms of PGs originating from a specific pathogen. Recently, a PGI

  18. Inhibition of foodborne pathogens by pomegranate juice.

    Science.gov (United States)

    Haghayeghi, Koorosh; Shetty, Kalidas; Labbé, Ronald

    2013-05-01

    Pomegranates have health-promoting benefits because of their polyphenol constituents. Previous studies have demonstrated the antimicrobial activity of aqueous and organic extracts of pomegranate components and by-products. We sought to determine the antimicrobial activity against 40 foodborne pathogens representing eight bacterial species using juice itself. In addition, we sought to determine the synergistic antimicrobial activity between pomegranate juice and other plant products displaying antimicrobial activity. The antimicrobial activity of pomegranate juice was dependent on the test organism, which varied to highly susceptible (four Gram-positive species) to unaffected (Salmonella and Escherichia coli O157:H7). Two Gram-negative species, which were inhibited were Helicobacter pylori and Vibrio parahemolyticus. No synergistic antimicrobial activity was seen between pomegranate and either barberry, oregano, or cranberry. The antimicrobial activity of pomegranate juice is dependent on the test organism and extraction method. The sensitivity of H. pylori suggests that pomegranate juice may be an alternative or supplemental treatment for gastric ulcers caused by this organism.

  19. Say it with me: stuttering inhibited.

    Science.gov (United States)

    Saltuklaroglu, Tim; Dayalu, Vikram N; Kalinowski, Joseph; Stuart, Andrew; Rastatter, Michael P

    2004-04-01

    This study examined fluency enhancement in people who stutter via the concomitant presentation of silently mouthed visual speech. Ten adults who stutter recited memorized text while watching another speaker silently mouth linguistically equivalent and linguistically different material. Relative to a control condition, in which no concomitant stimulus was provided, stuttering was reduced by 71% in the linguistically equivalent condition versus only 35% in the linguistically different condition. Despite being an 'incomplete' second speech signal, visual speech possesses the capacity to immediately and substantially enhance fluency when it is linguistically equivalent to the intended utterance. It is suggested that fluency enhancement via concomitantly presented external speech is achieved through the extraction of relevant speech gestures from the external speech signal that compliment the intended production, thereby compensating for possible internal inconsistencies in the matching of speech codes in people who stutter. As visual speech perception relies on fewer redundant cues to demarcate the intended gestures, when used as an external stuttering inhibitor, higher degrees of linguistic equivalence seem to be necessary for optimal stuttering inhibition.

  20. Aspirin, cyclooxygenase inhibition and colorectal cancer

    Institute of Scientific and Technical Information of China (English)

    Carlos; Sostres; Carla; Jerusalen; Gargallo; Angel; Lanas

    2014-01-01

    Colorectal cancer(CRC)is the third most common type of cancer worldwide.Screening measures are far from adequate and not widely available in resourcepoor settings.Primary prevention strategies therefore remain necessary to reduce the risk of developing CRC.Increasing evidence from epidemiological studies,randomized clinical trials and basic science supports the effectiveness of aspirin,as well as other non-steroidal anti-inflammatory drugs,for chemoprevention of several types of cancer,including CRC.This includes the prevention of adenoma recurrence and reduction of CRC incidence and mortality.The detectable benefit of daily low-dose aspirin(at least 75 mg),as used to prevent cardiovascular disease events,strongly suggests that its antiplatelet action is central to explaining its antitumor efficacy.Daily low-dose aspirin achieves complete and persistent inhibition of cyclooxygenase(COX)-1 in platelets(in pre-systemic circulation)while causing alimited and rapidly reversible inhibitory effect on COX-2and/or COX-1 expressed in nucleated cells.Aspirin has a short half-life in human circulation(about 20 minutes);nucleated cells have the ability to resynthesize acetylated COX isozymes within a few hours,while platelets do not.COX-independent mechanisms of aspirin have been suggested to explain its chemopreventive effects but this concept remains to be demonstrated in vivo at clinical doses.

  1. Stathmin potentiates vinflunine and inhibits Paclitaxel activity.

    Science.gov (United States)

    Malesinski, Soazig; Tsvetkov, Philipp O; Kruczynski, Anna; Peyrot, Vincent; Devred, François

    2015-01-01

    Cell biology and crystallographic studies have suggested a functional link between stathmin and microtubule targeting agents (MTAs). In a previous study we showed that stathmin increases vinblastine (VLB) binding to tubulin, and that conversely VLB increases stathmin binding to tubulin. This constituted the first biochemical evidence of the direct relationship between stathmin and an antimitotic drug, and revealed a new mechanism of action for VLB. The question remained if the observed interaction was specific for this drug or represented a general phenomenon for all MTAs. In the present study we investigated the binding of recombinant stathmin to purified tubulin in the presence of paclitaxel or another Vinca alkaloid, vinflunine, using Isothermal Titration Calorimetry (ITC). These experiments revealed that stathmin binding to tubulin is increased in the presence of vinflunine, whereas no signal is observed in the presence of paclitaxel. Further investigation using turbidity and co-sedimentation showed that stathmin inhibited paclitaxel microtubule-stabilizing activity. Taken together with the previous study using vinblastine, our results suggest that stathmin can be seen as a modulator of MTA activity and binding to tubulin, providing molecular explanation for multiple previous cellular and in vivo studies showing that stathmin expression level affects MTAs efficiency.

  2. Dihydroxyoctadecamonoenoate esters inhibit the neutrophil respiratory burst

    Indian Academy of Sciences (India)

    David Alan Thompson; Bruce D Hammock

    2007-03-01

    The leukotoxins [9(10)- and 12(13)-EpOME] are produced by activated inflammatory leukocytes such as neutrophils. High EpOME levels are observed in disorders such as acute respiratory distress syndrome and in patients with extensive burns. Although the physiological significance of the EpOMEs remains poorly understood, in some systems, the EpOMEs act as a protoxin, with their corresponding epoxide hydrolase metabolites, 9,10- and 12,13-DiHOME, specifically exerting toxicity. Both the EpOMEs and the DiHOMEs were also recently shown to have neutrophil chemotactic activity. We evaluated whether the neutrophil respiratory burst, a surge of oxidant production thought to play an important role in limiting certain bacterial and fungal infections, is modulated by members of the EpOME metabolic pathway. We present evidence that the DiHOMEs suppress the neutrophil respiratory burst by a mechanism distinct from that of respiratory burst inhibitors such as cyclosporin H or lipoxin A4, which inhibit multiple aspects of neutrophil activation.

  3. Inhibition of Complement Retards Ankylosing Spondylitis Progression

    Science.gov (United States)

    Yang, Chaoqun; Ding, Peipei; Wang, Qingkai; Zhang, Long; Zhang, Xin; Zhao, Jianquan; Xu, Enjie; Wang, Na; Chen, Jianfeng; Yang, Guang; Hu, Weiguo; Zhou, Xuhui

    2016-01-01

    Ankylosing spondylitis (AS) is a chronic axial spondyloarthritis (SpA) resulting in back pain and progressive spinal ankyloses. Currently, there are no effective therapeutics targeting AS largely due to elusive pathogenesis mechanisms, even as potential candidates such as HLA-B27 autoantigen have been identified. Herein, we employed a proteoglycan (PG)-induced AS mouse model together with clinical specimens, and found that the complement system was substantially activated in the spinal bone marrow, accompanied by a remarkable proportion alteration of neutrophils and macrophage in bone marrow and spleen, and by the significant increase of TGF-β1 in serum. The combined treatment with a bacteria-derived complement inhibitor Efb-C (C-terminal of extracellular fibrinogen-binding protein of Staphylococcus aureus) remarkably retarded the progression of mouse AS by reducing osteoblast differentiation. Furthermore, we demonstrated that two important modulators involved in AS disease, TGF-β1 and RANKL, were elevated upon in vitro complement attack in osteoblast and/or osteoclast cells. These findings further unravel that complement activation is closely related with the pathogenesis of AS, and suggest that complement inhibition may hold great potential for AS therapy. PMID:27698377

  4. Efficacy of ALK5 inhibition in myelofibrosis

    Science.gov (United States)

    Zhao, Wanke; Ho, Wanting Tina; Han, Ying; Murdun, Cem; Mailloux, Adam W.; Zhang, Ling; Wang, Xuefeng; Budhathoki, Anjali; Pradhan, Kith; Rapaport, Franck; Wang, Huaquan; Shao, Zonghong; Ren, Xiubao; Steidl, Ulrich; Levine, Ross L.; Zhao, Zhizhuang Joe; Verma, Amit; Epling-Burnette, Pearlie K.

    2017-01-01

    Myelofibrosis (MF) is a bone marrow disorder characterized by clonal myeloproliferation, aberrant cytokine production, extramedullary hematopoiesis, and bone marrow fibrosis. Although somatic mutations in JAK2, MPL, and CALR have been identified in the pathogenesis of these diseases, inhibitors of the Jak2 pathway have not demonstrated efficacy in ameliorating MF in patients. TGF-β family members are profibrotic cytokines and we observed significant TGF-β1 isoform overexpression in a large cohort of primary MF patient samples. Significant overexpression of TGF-β1 was also observed in murine clonal MPLW515L megakaryocytic cells. TGF-β1 stimulated the deposition of excessive collagen by mesenchymal stromal cells (MSCs) by activating the TGF-β receptor I kinase (ALK5)/Smad3 pathway. MSCs derived from MPLW515L mice demonstrated sustained overproduction of both collagen I and collagen III, effects that were abrogated by ALK5 inhibition in vitro and in vivo. Importantly, use of galunisertib, a clinically active ALK5 inhibitor, significantly improved MF in both MPLW515L and JAK2V617F mouse models. These data demonstrate the role of malignant hematopoietic stem cell (HSC)/TGF-β/MSC axis in the pathogenesis of MF, and provide a preclinical rationale for ALK5 blockade as a therapeutic strategy in MF.

  5. Hsp90 inhibition decreases mitochondrial protein turnover.

    Directory of Open Access Journals (Sweden)

    Daciana H Margineantu

    Full Text Available BACKGROUND: Cells treated with hsp90 inhibitors exhibit pleiotropic changes, including an expansion of the mitochondrial compartment, accompanied by mitochondrial fragmentation and condensed mitochondrial morphology, with ultimate compromise of mitochondrial integrity and apoptosis. FINDINGS: We identified several mitochondrial oxidative phosphorylation complex subunits, including several encoded by mtDNA, that are upregulated by hsp90 inhibitors, without corresponding changes in mRNA abundance. Post-transcriptional accumulation of mitochondrial proteins observed with hsp90 inhibitors is also seen in cells treated with proteasome inhibitors. Detailed studies of the OSCP subunit of mitochondrial F1F0-ATPase revealed the presence of mono- and polyubiquitinated OSCP in mitochondrial fractions. We demonstrate that processed OSCP undergoes retrotranslocation to a trypsin-sensitive form associated with the outer mitochondrial membrane. Inhibition of proteasome or hsp90 function results in accumulation of both correctly targeted and retrotranslocated mitochondrial OSCP. CONCLUSIONS: Cytosolic turnover of mitochondrial proteins demonstrates a novel connection between mitochondrial and cytosolic compartments through the ubiquitin-proteasome system. Analogous to defective protein folding in the endoplasmic reticulum, a mitochondrial unfolded protein response may play a role in the apoptotic effects of hsp90 and proteasome inhibitors.

  6. Effects of fencamfamine on latent inhibition.

    Science.gov (United States)

    Alves, Cilene R R; Delucia, Roberto; Silva, M Teresa A

    2002-10-01

    The effects of fencamfamine (FCF), an indirect dopamine (DA) agent, were investigated using the latent inhibition (LI) model of schizophrenia. In the LI procedure, rats preexposed (PE) to an unreinforced stimulus show difficulty in subsequent learning of an association in which that stimulus is predictive of an unconditioned stimulus (US). FCF (1.75, 3.5 and 7.0 mg/kg i.p.) yielded an inverse dose-response relationship regarding LI. At 3.5 mg/kg, LI was abolished and no effect was observed at 1.75 and 7.0 mg/kg. The effect of FCF (3.5 mg/kg) on LI was blocked by the antipsychotic risperidone (RIS; 4.0 mg/kg), a D2/5HT2 antagonist. These results confirm the similarity of the behavioral profile of FCF and amphetamine (AMPH). In addition, they provide a further validation of the LI model for psychosis, since RIS was shown to prevent a psychostimulant-induced disruption of LI.

  7. Inhibition of Midkine Augments Osteoporotic Fracture Healing.

    Directory of Open Access Journals (Sweden)

    Melanie Haffner-Luntzer

    Full Text Available The heparin-binding growth and differentiation factor midkine (Mdk is proposed to negatively regulate osteoblast activity and bone formation in the adult skeleton. As Mdk-deficient mice were protected from ovariectomy (OVX-induced bone loss, this factor may also play a role in the pathogenesis of postmenopausal osteoporosis. We have previously demonstrated that Mdk negatively influences bone regeneration during fracture healing. Here, we investigated whether the inhibition of Mdk using an Mdk-antibody (Mdk-Ab improves compromised bone healing in osteoporotic OVX-mice. Using a standardized femur osteotomy model, we demonstrated that Mdk serum levels were significantly enhanced after fracture in both non-OVX and OVX-mice, however, the increase was considerably greater in osteoporotic mice. Systemic treatment with the Mdk-Ab significantly improved bone healing in osteoporotic mice by increasing bone formation in the fracture callus. On the molecular level, we demonstrated that the OVX-induced reduction of the osteoanabolic beta-catenin signaling in the bony callus was abolished by Mdk-Ab treatment. Furthermore, the injection of the Mdk-Ab increased trabecular bone mass in the skeleton of the osteoporotic mice. These results implicate that antagonizing Mdk may be useful for the therapy of osteoporosis and osteoporotic fracture-healing complications.

  8. Bromodomains: Structure, function and pharmacology of inhibition.

    Science.gov (United States)

    Ferri, Elena; Petosa, Carlo; McKenna, Charles E

    2016-04-15

    Bromodomains are epigenetic readers of histone acetylation involved in chromatin remodeling and transcriptional regulation. The human proteome comprises 46 bromodomain-containing proteins with a total of 61 bromodomains, which, despite highly conserved structural features, recognize a wide array of natural peptide ligands. Over the past five years, bromodomains have attracted great interest as promising new epigenetic targets for diverse human diseases, including inflammation, cancer, and cardiovascular disease. The demonstration in 2010 that two small molecule compounds, JQ1 and I-BET762, potently inhibit proteins of the bromodomain and extra-terminal (BET) family with translational potential for cancer and inflammatory disease sparked intense efforts in academia and pharmaceutical industry to develop novel bromodomain antagonists for therapeutic applications. Several BET inhibitors are already in clinical trials for hematological malignancies, solid tumors and cardiovascular disease. Currently, the field faces the challenge of single-target selectivity, especially within the BET family, and of overcoming problems related to the development of drug resistance. At the same time, new trends in bromodomain inhibitor research are emerging, including an increased interest in non-BET bromodomains and a focus on drug synergy with established antitumor agents to improve chemotherapeutic efficacy. This review presents an updated view of the structure and function of bromodomains, traces the development of bromodomain inhibitors and their potential therapeutic applications, and surveys the current challenges and future directions of this vibrant new field in drug discovery. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Collagen hydrolysate inhibits zymosan-induced inflammation.

    Science.gov (United States)

    Hartog, Anita; Cozijnsen, Miranda; de Vrij, Gerrit; Garssen, Johan

    2013-07-01

    During the past years, evidence accumulated showing that glycine comprises anti-inflammatory activities. These effects occur, at least in part, via the activation of glycine-gated chloride channels (GlyR). Glycine is one of the major structural units of collagen, making up about 30% of the amino acids. This study aims to investigate the anti-inflammatory potential of collagen hydrolysate (CH) using the zymosan-induced ear-skin inflammation mouse model. After oral intake of 12.5, 25 or 50 mg CH the plasma levels of glycine increased in a concentration-dependent manner. CH was able to counteract zymosan-induced ear-skin inflammation locally (ear swelling) as well as systemically (IL-6 production by lipopolysaccharide (LPS)-stimulated whole blood cells). The LPS-stimulated IL-6 production in whole blood correlated positively with the ear swelling response. This correlation was abolished by strychnine (a glycine receptor antagonist), indicating the involvement of GlyR. Collectively, these data show that CH is able to modulate inflammatory responses both locally as well as systemically. This effect might be constituted by inhibiting pro-inflammatory cytokine production via GlyR.

  10. Mortalin inhibition in experimental Parkinson's disease.

    Science.gov (United States)

    Chiasserini, Davide; Tozzi, Alessandro; de Iure, Antonio; Tantucci, Michela; Susta, Federica; Orvietani, Pier Luigi; Koya, Keizo; Binaglia, Luciano; Calabresi, Paolo

    2011-08-01

    Among heat shock proteins, mortalin has been linked to the pathogenesis of Parkinson's disease. In the present work a rat model of Parkinson's disease was used to analyze the expression of striatal proteins and, more specifically, mortalin expression. The possible involvement of mortalin in Parkinson's disease pathogenesis was further investigated by utilizing an electrophysiological approach and pharmacological inhibition of mortalin in both the physiological and the parkinsonian states. Proteomic analysis was used to investigate changes in striatal protein expression in the 6-hydroxydopamine rat model of Parkinson's disease. The electrophysiological effects of MKT-077, a rhodamine-123 analogue acting as an inhibitor of mortalin, were measured by field potential recordings from corticostriatal brain slices obtained from control, sham-operated, and 6-hydroxydopamine-denervated animals. Slices in the presence of rotenone, an inhibitor of mitochondrial complex I, were also analyzed. Proteomic analysis revealed downregulation of mortalin in the striata of 6-hydroxydopamine-treated rats in comparison with sham-operated animals. MKT-077 reduced corticostriatal field potential amplitude in physiological conditions, inducing membrane depolarization and inward current in striatal medium spiny neurons. In addition, we observed that concentrations of MKT-077 not inducing any electrophysiological effect in physiological conditions caused significant changes in striatal slices from parkinsonian animals as well as in slices treated with a submaximal concentration of rotenone. These findings suggest a critical link between mortalin function and mitochondrial activity in both physiological and pathological conditions mimicking Parkinson's disease.

  11. Obesity inhibits lymphangiogenesis in prostate tumors.

    Science.gov (United States)

    Moreira, Ângela; Pereira, Sofia S; Machado, Christiane L; Morais, Tiago; Costa, Madalena; Monteiro, Mariana P

    2014-01-01

    Lymphangiogenesis is the process that leads to new lymphatic vessels formation from preexisting blood vessels in the presence of appropriate inducing signals, which in pathologic conditions such as cancer, may contribute to tumor cells dissemination. The aim of the present study was to study the role of obesity, leptin and insulin in tumor lymphangiogenesis. For that, we have quantified the lymphatic vessels in prostate tumors through their immunohistochemistry staining by Lyve-1 in RM1 prostate tumors induced in different obese mice models (ob/ob, db/db and diet induced obese (DIO) and in normal weight C57BL/6J mice (control). Lymph vessels density was determined by Lyve-1 immunohistochemistry of prostate adenocarcinomas, while the percentage of the Lyve-1 stained area and lymphatic vessels number were obtained using a morphometric computerized tool. Obese ob/ob and DIO mice presented prostate tumors that were significantly larger (pprostate tumors of DIO mice compared to tumors of db/db mice (pobesity may have a protective effect against prostate cancer dissemination by inhibiting lymphangiogenesis through a still unidentified mechanism that appears not to involve leptin or insulin.

  12. Vagus nerve stimulation inhibits cortical spreading depression.

    Science.gov (United States)

    Chen, Shih-Pin; Ay, Ilknur; de Morais, Andreia Lopes; Qin, Tao; Zheng, Yi; Sadeghian, Homa; Oka, Fumiaki; Simon, Bruce; Eikermann-Haerter, Katharina; Ayata, Cenk

    2016-04-01

    Vagus nerve stimulation has recently been reported to improve symptoms of migraine. Cortical spreading depression is the electrophysiological event underlying migraine aura and is a trigger for headache. We tested whether vagus nerve stimulation inhibits cortical spreading depression to explain its antimigraine effect. Unilateral vagus nerve stimulation was delivered either noninvasively through the skin or directly by electrodes placed around the nerve. Systemic physiology was monitored throughout the study. Both noninvasive transcutaneous and invasive direct vagus nerve stimulations significantly suppressed spreading depression susceptibility in the occipital cortex in rats. The electrical stimulation threshold to evoke a spreading depression was elevated by more than 2-fold, the frequency of spreading depressions during continuous topical 1 M KCl was reduced by ∼40%, and propagation speed of spreading depression was reduced by ∼15%. This effect developed within 30 minutes after vagus nerve stimulation and persisted for more than 3 hours. Noninvasive transcutaneous vagus nerve stimulation was as efficacious as direct invasive vagus nerve stimulation, and the efficacy did not differ between the ipsilateral and contralateral hemispheres. Our findings provide a potential mechanism by which vagus nerve stimulation may be efficacious in migraine and suggest that susceptibility to spreading depression is a suitable platform to optimize its efficacy.

  13. Inhibition of carcinogenesis by retinoids. [Review

    Energy Technology Data Exchange (ETDEWEB)

    Nettesheim, P.

    1979-01-01

    Progress made in recent years in the search for retinoids with anticarcinogenic activity is reviewed. There are many studies to be found in the literature which show no substantial effect of retinoids on carcinogenesis or tumor growth. Some of these negative findings may be related to the carcinogen dose used, the type of retinoid used, the dose, dose schedule or mode of administration of the retinoid. Others may indicate that the particular type of tumor or tumor system is, indeed, refractory to retinoids in general or to those retinoids that were tested. A great gap still exists in our knowledge concerning the pharmake-kinetics of most retinoids their availability to various normal and cancerous tissues, and the role and existence of transport and binding proteins. There are studies which indicate that under certain conditions, particularly conditions of topical application, some retinoids may even enhance carcinogenesis. It seems, however, indisputable by now that some retinoids are effective inhibitors of carcinogenesis in some organ systems and can even inhibit the growth of some established tumors. While the mechanisms of these inhibitory effects are presently not understood, it does seem clear that they are not mediated via the cytotoxic mechanisms typical of chemotherapeutic agents. The hope that retinoids might become an effective tool to halt the progression of some neoplastic diseases, seems to be justified.

  14. Inhibition of Oxidation in Nuclear Graphite

    Energy Technology Data Exchange (ETDEWEB)

    Phil Winston; James W. Sterbentz; William E. Windes

    2013-10-01

    Graphite is a fundamental material of high temperature gas cooled nuclear reactors, providing both structure and neutron moderation. Its high thermal conductivity, chemical inertness, thermal heat capacity, and high thermal structural stability under normal and off normal conditions contribute to the inherent safety of these reactor designs. One of the primary safety issues for a high temperature graphite reactor core is the possibility of rapid oxidation of the carbon structure during an off normal design basis event where an oxidizing atmosphere (air ingress) can be introduced to the hot core. Although the current Generation IV high temperature reactor designs attempt to mitigate any damage caused by a postualed air ingress event, the use of graphite components that inhibit oxidation is a logical step to increase the safety of these reactors. Recent experimental studies of graphite containing between 5.5 and 7 wt% boron carbide (B4C) indicate that oxidation is dramatically reduced even at prolonged exposures at temperatures up to 900°C. The proposed addition of B4C to graphite components in the nuclear core would necessarily be enriched in B-11 isotope in order to minimize B-10 neutron absorption and graphite swelling. The enriched boron can be added to the graphite during billet fabrication. Experimental oxidation rate results and potential applications for borated graphite in nuclear reactor components will be discussed.

  15. Simvastatin inhibits CD44 fragmentation in chondrocytes.

    Science.gov (United States)

    Terabe, Kenya; Takahashi, Nobunori; Takemoto, Toki; Knudson, Warren; Ishiguro, Naoki; Kojima, Toshihisa

    2016-08-15

    In human osteoarthritic chondrocytes, the hyaluronan receptor CD44 undergoes proteolytic cleavage at the cell surface. CD44 cleavage is thought to require transit of CD44 into cholesterol-rich lipid rafts. The purpose of this study was to investigate whether statins exert a protective effect on articular chondrocytes due to diminution of cholesterol. Three model systems of chondrocytes were examined including human HCS-2/8 chondrosarcoma cells, human osteoarthritic chondrocytes and normal bovine articular chondrocytes. Treatment with IL-1β + Oncostatin M resulted in a substantial increase in CD44 fragmentation in each of the three chondrocyte models. Pre-incubation with simvastatin prior to treatment with IL-1β + Oncostatin M decreased the level of CD44 fragmentation, decreased the proportion of CD44 that transits into the lipid raft fractions, decreased ADAM10 activity and diminished the interaction between CD44 and ADAM10. In HCS-2/8 cells and bovine articular chondrocytes, fragmentation of CD44 was blocked by the knockdown of ADAM10. Inhibition of CD44 fragmentation by simvastatin also resulted in improved retention of pericellular matrix. Addition of cholesterol and farnesyl-pyrophosphate reversed the protective effects of simvastatin. Thus, the addition of simvastatin exerts positive effects on chondrocytes including reduced CD44 fragmentation and enhanced the retention of pericellular matrix. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Rational drug design applied to myeloperoxidase inhibition.

    Science.gov (United States)

    Van Antwerpen, P; Zouaoui Boudjeltia, K

    2015-06-01

    Rational drug design is a general approach using protein-structure technique in which the discovery of a ligand can be driven either by chance, screening, or rational theory. Myeloperoxidase (MPO) was rapidly identified as a therapeutical target because of its involvement in chronic inflammatory syndromes. In this context, the research of MPO inhibitors was intensified and development of new chemical entities was rationally driven by the research of ligands that enter into the MPO catalytic pocket. Actually, as soon as crystallography data of MPO have become available and its structure was virtually designed, the rational drug design has been applied to this peroxidase. Pharmaceutical industries and academic laboratories apply rational drug design on MPO by either optimizing known inhibitors or searching new molecules by high-throughput virtual screening. By these ways, they were able to find efficient MPO inhibitors and understand their interactions with the enzyme. During this quest of MPO inhibition, it appears that Glu268 is a crucial residue in order to optimize ligand-target interaction. This amino acid should be carefully considered by medicinal chemist when they design inhibitors interfering with MPO activity.

  17. Aspirin, cyclooxygenase inhibition and colorectal cancer.

    Science.gov (United States)

    Sostres, Carlos; Gargallo, Carla Jerusalen; Lanas, Angel

    2014-02-01

    Colorectal cancer (CRC) is the third most common type of cancer worldwide. Screening measures are far from adequate and not widely available in resource-poor settings. Primary prevention strategies therefore remain necessary to reduce the risk of developing CRC. Increasing evidence from epidemiological studies, randomized clinical trials and basic science supports the effectiveness of aspirin, as well as other non-steroidal anti-inflammatory drugs, for chemoprevention of several types of cancer, including CRC. This includes the prevention of adenoma recurrence and reduction of CRC incidence and mortality. The detectable benefit of daily low-dose aspirin (at least 75 mg), as used to prevent cardiovascular disease events, strongly suggests that its antiplatelet action is central to explaining its antitumor efficacy. Daily low-dose aspirin achieves complete and persistent inhibition of cyclooxygenase (COX)-1 in platelets (in pre-systemic circulation) while causing a limited and rapidly reversible inhibitory effect on COX-2 and/or COX-1 expressed in nucleated cells. Aspirin has a short half-life in human circulation (about 20 minutes); nucleated cells have the ability to resynthesize acetylated COX isozymes within a few hours, while platelets do not. COX-independent mechanisms of aspirin have been suggested to explain its chemopreventive effects but this concept remains to be demonstrated in vivo at clinical doses.

  18. Stathmin potentiates vinflunine and inhibits Paclitaxel activity.

    Directory of Open Access Journals (Sweden)

    Soazig Malesinski

    Full Text Available Cell biology and crystallographic studies have suggested a functional link between stathmin and microtubule targeting agents (MTAs. In a previous study we showed that stathmin increases vinblastine (VLB binding to tubulin, and that conversely VLB increases stathmin binding to tubulin. This constituted the first biochemical evidence of the direct relationship between stathmin and an antimitotic drug, and revealed a new mechanism of action for VLB. The question remained if the observed interaction was specific for this drug or represented a general phenomenon for all MTAs. In the present study we investigated the binding of recombinant stathmin to purified tubulin in the presence of paclitaxel or another Vinca alkaloid, vinflunine, using Isothermal Titration Calorimetry (ITC. These experiments revealed that stathmin binding to tubulin is increased in the presence of vinflunine, whereas no signal is observed in the presence of paclitaxel. Further investigation using turbidity and co-sedimentation showed that stathmin inhibited paclitaxel microtubule-stabilizing activity. Taken together with the previous study using vinblastine, our results suggest that stathmin can be seen as a modulator of MTA activity and binding to tubulin, providing molecular explanation for multiple previous cellular and in vivo studies showing that stathmin expression level affects MTAs efficiency.

  19. Decoupled echo state networks with lateral inhibition.

    Science.gov (United States)

    Xue, Yanbo; Yang, Le; Haykin, Simon

    2007-04-01

    Building on some prior work, in this paper we describe a novel structure termed the decoupled echo state network (DESN) involving the use of lateral inhibition. Two low-complexity implementation schemes, namely, the DESN with reservoir prediction (DESN + RP) and DESN with maximum available information (DESN + MaxInfo), are developed: (1) In the multiple superimposed oscillator (MSO) problem, DESN + MaxInfo exhibits three important attributes: lower generalization mean-square error (MSE), better robustness with respect to the random generation of reservoir weight matrix and feedback connections, and robustness to variations in the sparseness of reservoir weight matrix, compared to DESN + RP. (2) For a noiseless nonlinear prediction task, DESN + RP outperforms the DESN + MaxInfo and single reservoir-based ESN approach in terms of lower prediction MSE and better robustness to a change in the number of inputs and sparsity of the reservoir weight matrix. Finally, in a real-life prediction task using noisy sea clutter data, both schemes exhibit higher prediction accuracy and successful design ratio than a conventional ESN with a single reservoir.

  20. The Role of Test Context in Latent Inhibition of Conditioned Inhibition: Part of a Search for General Principles of Associative Interference

    OpenAIRE

    Miguez, Gonzalo; Soares, Julia S.; Miller, Ralph R.

    2015-01-01

    Two lick-suppression experiments with rats assessed interference with behavior indicative of conditioned inhibition by a latent inhibition treatment as a function of test context. We asked what effect the test context has, given identical latent inhibition treatment in Phase 1 and identical conditioned inhibition training in Phase 2. In Experiment 1, an AAA vs. AAB context-shift design determined that latent inhibition treatment in Phase 1 attenuated behavior indicative of conditioned inhibit...

  1. Response of barley aleurone layers to abscisic acid

    Energy Technology Data Exchange (ETDEWEB)

    Ho, D.T.H.; Varner, J.E.

    1976-02-01

    Cordycepin, an inhibitor of RNA synthesis in barley (Hordeum vulgare L.) aleurone cells, does not inhibit the gibberellic acid-enhanced ..cap alpha..-amylase (EC 3.2.1.1.) synthesis in barley aleurone layers if it is added 12 hours or more after the addition of the hormone. However, the accumulation of ..cap alpha..-amylase activity after 12 hours of gibberellic acid can be decreased by abscisic acid. The accumulation of ..cap alpha..-amylase activity is sustained or quickly restored when cordycepin is added simultaneously or some time after abscisic acid, indicating that the response of aleurone layers to abscisic acid depends on the continuous synthesis of a short lived RNA. By analysis of the newly synthesized proteins by gel electrophoresis with sodium dodecylsulfate, it was observed that the synthesis of ..cap alpha..-amylase is decreased in the presence of abscisic acid while the synthesis of most of the other proteins remains unchanged. From the rate of resumption of ..cap alpha..-amylase production in the presence of cordycepin and abscisic acid, it appears that abscisic acid does not have a measurable effect on the stability of ..cap alpha..-amylase mRNA.

  2. Attention Inhibition Training Can Reduce Betel-Nut Chewing Time

    Directory of Open Access Journals (Sweden)

    Ming-Chou Ho

    2011-05-01

    Full Text Available Betel nut (or areca is the fourth most commonly used drug worldwide after tobacco, alcohol, and caffeine. Many chemical ingredients of betel nut are carcinogenic. We examined whether the manipulation of attentional inhibition toward the areca-related stimuli could affect betel-nut chewing time. Three matched groups of habitual chewers were recruited: inhibit-areca, inhibit-non-areca, and control. This study consisted of a Go/No-Go task for inhibition training, followed by a taste test for observing chewing behavior. The Go/No-Go task constituted three phases (pretest, training and posttest. In the taste test, the habitual chewers were asked to rate the flavors of one betel nut and one gum. The purpose (blind to the chewers of this taste test was to observe whether their picking order and chewing time were affected by experimental manipulation. Results from the Go/No-Go task showed successful training. Further, the training groups (the inhibit-areca and inhibit-non-areca groups showed a significant reduction in betel nut chewing time, in comparison to the control group. Since both training groups showed reduced chewing time, the inhibition training may affect general control ability, in regardless of the stimulus (areca or not to be inhibited. Reduced chewing time is important for reducing areca-related diseases.

  3. Forgetting the Literal: The Role of Inhibition in Metaphor Comprehension

    Science.gov (United States)

    George, Tim; Wiley, Jennifer

    2016-01-01

    In order for a person to comprehend metaphoric expressions, do metaphor-irrelevant aspects of literal information need to be inhibited? Previous research using sentence-verification paradigms has found that literal associates take longer to process after reading metaphorical sentences; however, it is problematic to infer inhibition from this…

  4. An alternative inhibition method for determining cross-reactive allergens

    NARCIS (Netherlands)

    Schmidt-Hieltjes, Yvonne; Teodorowicz, Malgorzata; Jansen, Ad; Hartog, Den Gerco; Elfvering-Berendsen, Lisette; Jong, De Nicolette W.; Savelkoul, Huub F.J.; Ruinemans-Koerts, Janneke

    2017-01-01

    Inhibition assays are an useful tool to identify the allergen of primary sensitization of cross-reactive allergens. Classical ELISA-based inhibition assays are limited by both the availability of commercial standardized allergen extracts and the experience and knowledge needed for making home-made e

  5. Stuttering Inhibition via Altered Auditory Feedback during Scripted Telephone Conversations

    Science.gov (United States)

    Hudock, Daniel; Kalinowski, Joseph

    2014-01-01

    Background: Overt stuttering is inhibited by approximately 80% when people who stutter read aloud as they hear an altered form of their speech feedback to them. However, levels of stuttering inhibition vary from 60% to 100% depending on speaking situation and signal presentation. For example, binaural presentations of delayed auditory feedback…

  6. Cognitive Inhibition in Students with and without Dyslexia and Dyscalculia

    Science.gov (United States)

    Wang, Li-Chih; Tasi, Hung-Ju; Yang, Hsien-Ming

    2012-01-01

    The present study presents a comparison of the cognitive inhibition abilities of dyslexic, dyscalculic, and control students. The participants were 45 dyslexic students, 45 dyscalculic students, and 45 age-, gender-, and IQ-matched control students. The major evaluation tools included six cognitive inhibition tasks which were restructured during…

  7. Distractor Inhibition: Principles of Operation during Selective Attention

    Science.gov (United States)

    Wyatt, Natalie; Machado, Liana

    2013-01-01

    Research suggests that although target amplification acts as the main determinant of the efficacy of selective attention, distractor inhibition contributes under some circumstances. Here we aimed to gain insight into the operating principles that regulate the use of distractor inhibition during selective attention. The results suggest that, in…

  8. Effective inhibition of viral reproduction by hydrophobised antiviral antibodies.

    Science.gov (United States)

    Kabanov, A V; Ovcharenko, A V; Melik-Nubarov, N S; Bannikov, A I; Lisok, T P; Klyushnenkova, E V; Cherchenko, N G; Alakhov VYu; Levashov, A V; Kiselev, V I

    1990-01-01

    A method is proposed for the inhibition of viral reproduction in cells by means of fatty-acylated antiviral antibodies which, in contrast to the unmodified antibodies, have the ability to enter the cells. The potential of this technique is demonstrated in experiments involving inhibition of the reproduction of various strains of influenza virus and respiratory syncytial virus.

  9. Executive functioning in boys with ADHD: primarily an inhibition deficit?

    NARCIS (Netherlands)

    Scheres, A.P.J.; Oosterlaan, J.; Geurts, H.M.; Morein-Zamir, S.; Meiran, N.; Vlasveld, L.; Sergeant, J.A.

    2004-01-01

    This study was aimed at: (1) testing whether boys with Attention Deficit/Hyperactivity Disorder (ADHD) demonstrate a deficit in response inhibition and deficits in other executive functions (EF), or alternatively, demonstrate a deficit in only response inhibition; (2) investigating which role associ

  10. Stuttering Inhibition via Altered Auditory Feedback during Scripted Telephone Conversations

    Science.gov (United States)

    Hudock, Daniel; Kalinowski, Joseph

    2014-01-01

    Background: Overt stuttering is inhibited by approximately 80% when people who stutter read aloud as they hear an altered form of their speech feedback to them. However, levels of stuttering inhibition vary from 60% to 100% depending on speaking situation and signal presentation. For example, binaural presentations of delayed auditory feedback…

  11. A Subinhibitory Concentration of Clarithromycin Inhibits Mycobacterium avium Biofilm Formation

    OpenAIRE

    2004-01-01

    Mycobacterium avium causes disseminated infection in immunosuppressed individuals and lung infection in patients with chronic lung diseases. M. avium forms biofilm in the environment and possibly in human airways. Antibiotics with activity against the bacterium could inhibit biofilm formation. Clarithromycin inhibits biofilm formation but has no activity against established biofilm.

  12. 46 CFR 154.1740 - Vinyl chloride: Inhibiting and inerting.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Vinyl chloride: Inhibiting and inerting. 154.1740... Operating Requirements § 154.1740 Vinyl chloride: Inhibiting and inerting. When a vessel is carrying vinyl chloride, the master shall ensure that: (a) Section 154.1818 is met; or (b) Section 154.1710 is met,...

  13. The role of non-CRF inhibition in contour detection

    NARCIS (Netherlands)

    Grigorescu, Cosmin; Petkov, Nicolai; Westenberg, Michel A.; Skala,

    2003-01-01

    We propose a biologically motivated computational step, called non-classical receptive field (non-CRF) inhibition, to improve the performance of contour detectors. Non-CRF inhibition is exhibited by 80% of the orientation selective neurons in the primary visual cortex of macaque monkeys and has been

  14. Corrosion Inhibition of High Speed Steel by Biopolymer HPMC Derivatives

    OpenAIRE

    Shih-Chen Shi; Chieh-Chang Su

    2016-01-01

    The corrosion inhibition characteristics of the derivatives of biopolymer hydroxypropyl methylcellulose (HPMC), hydroxypropyl methylcellulose phthalate (HPMCP), and hydroxypropyl methylcellulose acetate succinate (HPMCAS) film are investigated. Based on electrochemical impedance spectroscopic measurements and potentiodynamic polarization, the corrosion inhibition performance of high speed steel coated with HPMC derivatives is evaluated. The Nyquist plot and Tafel polarization demonstrate prom...

  15. Corrosion Inhibition of Aluminium by Capparis deciduas in Acidic Media

    Directory of Open Access Journals (Sweden)

    P. Arora

    2007-01-01

    Full Text Available The inhibition efficiency of ethanolic extract of different parts of Capparis deciduas (Ker in acidic medium has been evaluated by mass loss and thermometric methods. Values of inhibition efficiency obtained from the two methods are in good agreement and are dependent upon the concentration of inhibitor and acid.

  16. Underlying Personality Characteristics of Behavioral Inhibition in Children

    Science.gov (United States)

    Muris, Peter; Dietvorst, Roeland

    2006-01-01

    Behavioral inhibition refers to the tendency of children to be unusually shy and to react with fear and withdrawal in situations that are novel and/or unfamiliar, and is generally regarded as a vulnerability factor for developing anxiety disorders. The present study investigated the hypothesis that behavioral inhibition is characterized by a…

  17. The Root-inhibiting Substance of Allium Cepa

    NARCIS (Netherlands)

    Stolk, Anth.

    1953-01-01

    Whereas scientific research on inhibiting substances has mainly occupied itself with the effect of these substances on the germination process, I was able to demonstrate the presence of a root-inhibiting agent during my studies on root formation in Fuchsia hybrida and Pelargonium zonale (Stolk, 1952

  18. The Affective Consequences of Cognitive Inhibition: Devaluation or Neutralization?

    Science.gov (United States)

    Frischen, Alexandra; Ferrey, Anne E.; Burt, Dustin H. R.; Pistchik, Meghan; Fenske, Mark J.

    2012-01-01

    Affective evaluations of previously ignored visual stimuli are more negative than those of novel items or prior targets of attention or response. This has been taken as evidence that inhibition has negative affective consequences. But inhibition could act instead to attenuate or "neutralize" preexisting affective salience, predicting opposite…

  19. Corrosion inhibition of carbon steel by sodium metavanadate

    Directory of Open Access Journals (Sweden)

    VIJAYA GOPAL SRIBHARATHY

    2012-08-01

    Full Text Available The inhibition efficiency of sodium metavanadate (SMV-adipic acid (AA system in controlling corrosion of carbon steel in an aqueous solution containing 60 ppm of Cl- has been evaluated by weight-loss method; 250 ppm of SMV exhibits inhibition efficiency of 56 %. Addition of adipic acid to SMV improves the inhibition efficiency of the system. The formulation consisting of 250 ppm of SMV and 250 ppm of adipic acid has inhibition efficiency of 98 %. A synergistic effect exists between SMV and adipic acid with the synergism parameters greater than 1. Mecha¬nistic aspects of corrosion inhibition have been studied by electrochemical methods like potentiodynamic polarization and electrochemical impedance spectroscopy. FTIR spectra reveal that the protective film consists of Fe2+-SMV complex and Fe2+-adipic acid complex. The protective film has been analyzed by fluorescence spectra, SEM and EDAX.

  20. Sulindac Sulfide, but Not Sulindac Sulfone, Inhibits Colorectal Cancer Growth

    Directory of Open Access Journals (Sweden)

    Christopher S. Williams

    1999-06-01

    Full Text Available Sulindac sulfide, a metabolite of the nonsteroidal antiinflammatory drug (NSAID sulindac sulfoxide, is effective at reducing tumor burden in both familial adenomatous polyposis patients and in animals with colorectal cancer. Another sulindac sulfoxide metabolite, sulindac sulfone, has been reported to have antitumor properties without inhibiting cyclooxygenase activity. Here we report the effect of sulindac sulfone treatment on the growth of colorectal carcinoma cells. We observed that sulindac sulfide or sulfone treatment of HCA-7 cells led to inhibition of prostaglandin E2 production. Both sulindac sulfide and sulfone inhibited HCA-7 and HCT-116 cell growth in vitro. Sulindac sulfone had no effect on the growth of either HCA-7 or HCT-116 xenografts, whereas the sulfide derivative inhibited HCA-7 growth in vivo. Both sulindac sulfide and sulfone inhibited colon carcinoma cell growth and prostaglandin production in vitro, but sulindac sulfone had no effect on the growth of colon cancer cell xenografts in nude mice.