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Author Miler, M.; Sosic-Jurjevic, B.; Nestorovic, N.; Ristic, N.; Medigovic, I.; Savin, S.; Milosevic, V. url  doi
openurl 
  Title Morphological and functional changes in pituitary-thyroid axis following prolonged exposure of female rats to constant light Type Journal Article
  Year 2014 Publication Journal of Morphology Abbreviated Journal J Morphol  
  Volume 275 Issue 10 Pages 1161-1172  
  Keywords TSH cells; constant light; immunohistochemistry; pituitary; rat; thyroid; light exposure  
  Abstract Light regulates numerous physiological functions and synchronizes them with the environment, in part by adjusting secretion of different hormones. We hypothesized that constant light (CL) would disturb pituitary-thyroid axis. Our aim was to determine morphological and functional changes in this endocrine system in such extreme conditions and, based on the obtained results, to propose the underlying mechanism(s). Starting from the thirtieth postnatal day, female Wistar rats were exposed to CL (600 lx) for the following 95 days. The controls were maintained under the regular laboratory lighting conditions. After decapitation, pituitaries and thyroids were prepared for further histomorphometric, immunohistochemical, and immunofluorescence examinations. Concentration of thyroid stimulating hormone (TSH), total T4 and T3 (TH) were determined. Thyroid tissue of light-treated rats was characterized by microfollicular structure. We detected no change in total thyroid volume, localization and accumulation of thyroglobulin, thyroid peroxidase, and sodium-iodide symporter in the follicular epithelium of CL rats. The volume of follicular epithelium and activation index were increased, while volume of the colloid and serum levels of TH decreased. In the pituitary, the relative intensity of TSH beta-immunofluorescence signal within the cytoplasm of thyrotrophs increased, but their average cell volume and the relative volume density decreased. Serum TSH was unaltered. We conclude that exposure of female rats to CL induced alterations in pituitary-thyroid axis. Thyroid tissue was characterized by microfollicular structure. Serum TH levels were reduced without accompanying increase in serum TSH. We hypothesize that increased secretion and clearance of TH together with unchanged or even decreased hormonal synthesis, resulted in decreased serum TH levels in CL group. We assume this decrease consequently led to increased synthesis and/or accumulation of pituitary TSH. However, decreased average TSH cell volume and relative volume density, together with unchanged serum TSH, point to additional, negative regulation of thyrotrophs. J. Morphol., 2014. (c) 2014 Wiley Periodicals, Inc.  
  Address Department of Cytology, Institute for Biological Research “Sinisa Stankovic,” University of Belgrade, Belgrade, Serbia  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-2887 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:24797691 Approved no  
  Call Number (up) IDA @ john @ Serial 304  
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Author van der Burght, B.W.; Hansen, M.; Olsen, J.; Zhou, J.; Wu, Y.; Nissen, M.H.; Sparrow, J.R. url  doi
openurl 
  Title Early changes in gene expression induced by blue light irradiation of A2E-laden retinal pigment epithelial cells Type Journal Article
  Year 2013 Publication Acta Ophthalmologica Abbreviated Journal Acta Ophthalmol  
  Volume 91 Issue 7 Pages e537-45  
  Keywords Apoptosis; Cell Line; Cell Survival; Gene Expression Regulation/*physiology; Humans; Light; Lipofuscin/genetics; Oligonucleotide Array Sequence Analysis; Principal Component Analysis; Pyridinium Compounds; RNA, Messenger/genetics; Real-Time Polymerase Chain Reaction; Retinal Pigment Epithelium/metabolism/pathology/*radiation effects; Retinoids/*genetics; Transcriptome; A2e; age-related macular degeneration; apoptosis; complement cascade; gene expression; retinal pigment epithelial cells; blue light; retinal pigment epithelial; epigenetics  
  Abstract PURPOSE: Accumulation of bisretinoids as lipofuscin in retinal pigment epithelial (RPE) cells is implicated in the pathogenesis of some blinding diseases including age-related macular degeneration (AMD). To identify genes whose expression may change under conditions of bisretinoid accumulation, we investigated the differential gene expression in RPE cells that had accumulated the lipofuscin fluorophore A2E and were exposed to blue light (430 nm). METHODS: A2E-laden RPE cells were exposed to blue light (A2E/430 nm) at various time intervals. Cell death was quantified using Dead Red staining, and RNA levels for the entire genome was determined using DNA microarrays (Affymetrix GeneChip Human Genome 2.0 Plus). Array results for selected genes were confirmed by real-time reverse-transcriptase polymerase chain reaction. RESULTS: Principal component analysis revealed that the A2E-laden RPE cells irradiated with blue light were clearly distinguishable from the control samples. We found differential regulation of genes belonging to the following functional groups: transcription factors, stress response, apoptosis and immune response. Among the last mentioned were downregulation of four genes that coded for proteins that have an inhibitory effect on the complement cascade: (complement factor H, complement factor H-related 1, complement factor I and vitronectin) and of two belonging to the classical pathway (complement component 1, s subcomponent and complement component 1, r subcomponent). CONCLUSION: This study demonstrates that blue light irradiation of A2E-laden RPE cells can alter the transcription of genes belonging to different functional pathways including stress response, apoptosis and the immune response. We suggest that these molecules may be associated to the pathogenesis of AMD and can potentially serve as future therapeutic targets.  
  Address Department of International Health, Immunology and Microbiology, Eye Research Unit, University of Copenhagen, Copenhagen, DenmarkDepartment of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, DenmarkDepartment of Ophthalmology, Columbia University, New York, New York, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1755-375X ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23742627 Approved no  
  Call Number (up) IDA @ john @ Serial 346  
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Author Lucas, R.J.; Peirson, S.N.; Berson, D.M.; Brown, T.M.; Cooper, H.M.; Czeisler, C.A.; Figueiro, M.G.; Gamlin, P.D.; Lockley, S.W.; O'Hagan, J.B.; Price, L.L.A.; Provencio, I.; Skene, D.J.; Brainard, G.C. url  doi
openurl 
  Title Measuring and using light in the melanopsin age Type Journal Article
  Year 2014 Publication Trends in Neurosciences Abbreviated Journal Trends Neurosci  
  Volume 37 Issue 1 Pages 1-9  
  Keywords Editorial; Animals; Circadian Rhythm/physiology; Humans; Photoreceptor Cells/metabolism; Phototherapy/*trends; Retinal Ganglion Cells/metabolism; Rod Opsins/*physiology  
  Abstract Light is a potent stimulus for regulating circadian, hormonal, and behavioral systems. In addition, light therapy is effective for certain affective disorders, sleep problems, and circadian rhythm disruption. These biological and behavioral effects of light are influenced by a distinct photoreceptor in the eye, melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs), in addition to conventional rods and cones. We summarize the neurophysiology of this newly described sensory pathway and consider implications for the measurement, production, and application of light. A new light-measurement strategy taking account of the complex photoreceptive inputs to these non-visual responses is proposed for use by researchers, and simple suggestions for artificial/architectural lighting are provided for regulatory authorities, lighting manufacturers, designers, and engineers.  
  Address Department of Neurology, Thomas Jefferson University, Philidelphia, PA, USA. Electronic address: George.Brainard@jefferson.edu  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0166-2236 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:24287308 Approved no  
  Call Number (up) LoNNe @ christopher.kyba @ Serial 457  
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Author Chamorro, E.; Bonnin-Arias, C.; Perez-Carrasco, M.J.; Munoz de Luna, J.; Vazquez, D.; Sanchez-Ramos, C. url  doi
openurl 
  Title Effects of light-emitting diode radiations on human retinal pigment epithelial cells in vitro Type Journal Article
  Year 2013 Publication Photochemistry and Photobiology Abbreviated Journal Photochem Photobiol  
  Volume 89 Issue 2 Pages 468-473  
  Keywords Human Health; Apoptosis/*radiation effects; Biological Markers/metabolism; Caspases/metabolism; Cell Survival/radiation effects; DNA Damage; Epithelial Cells/cytology/metabolism/*radiation effects; Histones/metabolism; Humans; Light; Membrane Potential, Mitochondrial/*radiation effects; Mitochondria/*radiation effects; Photoperiod; Primary Cell Culture; Reactive Oxygen Species/metabolism; Retinal Pigment Epithelium/cytology/metabolism/*radiation effects  
  Abstract Human visual system is exposed to high levels of natural and artificial lights of different spectra and intensities along lifetime. Light-emitting diodes (LEDs) are the basic lighting components in screens of PCs, phones and TV sets; hence it is so important to know the implications of LED radiations on the human visual system. The aim of this study was to investigate the effect of LEDs radiations on human retinal pigment epithelial cells (HRPEpiC). They were exposed to three light-darkness (12 h/12 h) cycles, using blue-468 nm, green-525 nm, red-616 nm and white light. Cellular viability of HRPEpiC was evaluated by labeling all nuclei with DAPI; Production of reactive oxygen species (ROS) was determined by H2DCFDA staining; mitochondrial membrane potential was quantified by TMRM staining; DNA damage was determined by H2AX histone activation, and apoptosis was evaluated by caspases-3,-7 activation. It is shown that LED radiations decrease 75-99% cellular viability, and increase 66-89% cellular apoptosis. They also increase ROS production and DNA damage. Fluorescence intensity of apoptosis was 3.7% in nonirradiated cells and 88.8%, 86.1%, 83.9% and 65.5% in cells exposed to white, blue, green or red light, respectively. This study indicates three light-darkness (12 h/12 h) cycles of exposure to LED lighting affect in vitro HRPEpiC.  
  Address Neuro-Computing and Neuro-Robotics Research Group, Universidad Complutense de Madrid, Madrid, Spain. eva.chamorro@opt.ucm.es  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0031-8655 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:22989198 Approved no  
  Call Number (up) LoNNe @ christopher.kyba @ Serial 511  
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Author van Diepen, H.C.; Foster, R.G.; Meijer, J.H. url  doi
openurl 
  Title A colourful clock Type Journal Article
  Year 2015 Publication PLoS Biology Abbreviated Journal PLoS Biol  
  Volume 13 Issue 5 Pages e1002160  
  Keywords Animals; Commentary; *Circadian Rhythm; suprachiasmatic nuclei; melanopsin; retinal ganglion cells; entrainment; photoperiod  
  Abstract Circadian rhythms are an essential property of life on Earth. In mammals, these rhythms are coordinated by a small set of neurons, located in the suprachiasmatic nuclei (SCN). The environmental light/dark cycle synchronizes (entrains) the SCN via a distinct pathway, originating in a subset of photosensitive retinal ganglion cells (pRGCs) that utilize the photopigment melanopsin (OPN4). The pRGCs are also innervated by rods and cones and, so, are both endogenously and exogenously light sensitive. Accumulating evidence has shown that the circadian system is sensitive to ultraviolet (UV), blue, and green wavelengths of light. However, it was unclear whether colour perception itself can help entrain the SCN. By utilizing both behavioural and electrophysiological recording techniques, Walmsley and colleagues show that multiple photic channels interact and enhance the capacity of the SCN to synchronize to the environmental cycle. Thus, entrainment of the circadian system combines both environmental irradiance and colour information to ensure that internal and external time are appropriately aligned.  
  Address Laboratory for Neurophysiology, Department of Molecular Cell Biology, Leiden University medical School, Leiden, The Netherlands  
  Corporate Author Thesis  
  Publisher PLOS Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1544-9173 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:25996907; PMCID:PMC4440787 Approved no  
  Call Number (up) LoNNe @ christopher.kyba @ Serial 1183  
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