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Author Masis-Vargas, A.; Ritsema, W.I.G.R.; Mendoza, J.; Kalsbeek, A. url  doi
openurl 
  Title Metabolic Effects of Light at Night are Time- and Wavelength-Dependent in Rats Type Journal Article
  Year 2020 Publication Obesity (Silver Spring, Md.) Abbreviated Journal Obesity (Silver Spring)  
  Volume 28 Suppl 1 Issue Pages S114-S125  
  Keywords (up) Animals  
  Abstract OBJECTIVE: Intrinsically photosensitive retinal ganglion cells are most sensitive to short wavelengths and reach brain regions that modulate biological rhythms and energy metabolism. The increased exposure nowadays to artificial light at night (ALAN), especially short wavelengths, perturbs our synchronization with the 24-hour solar cycle. Here, the time- and wavelength dependence of the metabolic effects of ALAN are investigated. METHODS: Male Wistar rats were exposed to white, blue, or green light at different time points during the dark phase. Locomotor activity, energy expenditure, respiratory exchange ratio (RER), and food intake were recorded. Brains, livers, and blood were collected. RESULTS: All wavelengths decreased locomotor activity regardless of time of exposure, but changes in energy expenditure were dependent on the time of exposure. Blue and green light reduced RER at Zeitgeber time 16-18 without changing food intake. Blue light increased period 1 (Per1) gene expression in the liver, while green and white light increased Per2. Blue light decreased plasma glucose and phosphoenolpyruvate carboxykinase (Pepck) expression in the liver. All wavelengths increased c-Fos activity in the suprachiasmatic nucleus, but blue and green light decreased c-Fos activity in the paraventricular nucleus. CONCLUSIONS: ALAN affects locomotor activity, energy expenditure, RER, hypothalamic c-Fos expression, and expression of clock and metabolic genes in the liver depending on the time of day and wavelength.  
  Address Hypothalamic Integration Mechanisms, Netherlands Institute for Neuroscience (NIN), Amsterdam, The Netherlands  
  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 1930-7381 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:32700824 Approved no  
  Call Number GFZ @ kyba @ Serial 3081  
Permanent link to this record
 

 
Author Prabhat, A.; Malik, I.; Jha, N.A.; Bhardwaj, S.K.; Kumar, V. url  doi
openurl 
  Title Developmental effects of constant light on circadian behaviour and gene expressions in zebra finches: Insights into mechanisms of metabolic adaptation to aperiodic environment in diurnal animals Type Journal Article
  Year 2020 Publication Journal of Photochemistry and Photobiology B: Biology Abbreviated Journal Journal of Photochemistry and Photobiology B: Biology  
  Volume in press Issue Pages 111995  
  Keywords (up) Animals  
  Abstract A most crucial feature of biological adaptation is the maintenance of a close temporal relationship of behaviour and physiology with prevailing 24-h light-dark environment, which is rapidly changing with increasing nighttime illumination. This study investigated developmental effects of the loss of night on circadian behaviour, metabolism and gene expressions in diurnal zebra finches born and raised under LL, with controls on 12 L:12D. Birds under LD were entrained, and showed normal body mass and a significant 24-h rhythm in both activity-rest pattern and mRNA expression of candidate genes that we measured. But, under LL, birds gained weight and accumulated lipid in the liver. Intriguingly, at the end of the experiment, the majority (4/5th) of birds under LL were rhythmic in activity despite arrhythmic expression in the hypothalamus of c-Fos (neuronal activity), Rhodopsin and Mel1-a genes (light perception), and clock genes (Bmal1, Per2 and Rev-erb β). In peripheral tissues, LL induced variable clock gene expressions. Whereas 24-h mRNA rhythm was abolished for Bmal1 in both liver and gut, it persisted for Per2 and Rev-erb β in liver, and for Per2 in gut. Further, we found under LL, the loss of 24-h rhythm in hepatic expression of Fasn and Cd36/Fat (biosynthesis and its uptake), and gut expression of Sglt1, Glut5, Cd36 and Pept1 (nutrient absorption) genes. As compared to LD, baseline mRNA levels of Fasn and Cd36 genes were attenuated under LL. Among major transporter genes, Sglt1 (glucose) and Cd36 (fat) genes were arrhythmic, while Glut5 (glucose) and Pept1 (protein) genes were rhythmic but with phase differences under LL, compared to LD. These results demonstrate dissociation of circadian behaviour from clock gene rhythms, and provide molecular insights into possible mechanisms at different levels (behaviour and physiology) that diurnal animals might employ in order to adapt to an emerging overly illuminated-night urban environment.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1011-1344 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 3085  
Permanent link to this record
 

 
Author Wei, L.; Yue, F.; Xing, L.; Wu, S.; Shi, Y.; Li, J.; Xiang, X.; Lam, S.M.; Shui, G.; Russell, R.; Zhang, D. url  doi
openurl 
  Title Constant Light Exposure Alters Gut Microbiota and Promotes the Progression of Steatohepatitis in High Fat Diet Rats Type Journal Article
  Year 2020 Publication Frontiers in Microbiology Abbreviated Journal Front. Microbiol.  
  Volume 11 Issue Pages  
  Keywords (up) Animals  
  Abstract Background: Non-alcoholic fatty liver disease (NAFLD) poses a significant health concern worldwide. With the progression of urbanization, light pollution may be a previously unrecognized risk factor for NAFLD/NASH development. However, the role of light pollution on NAFLD is insufficiently understood, and the underlying mechanism remains unclear. Interestingly, recent studies indicate the gut microbiota affects NAFLD/NASH development. Therefore, the present study explored effects of constant light exposure on NAFLD and its related microbiotic mechanisms.

Materials and Methods: Twenty-eight SD male rats were divided into four groups (n = 7 each): rats fed a normal chow diet, and exposed to standard light-dark cycle (ND-LD); rats fed a normal chow diet, and exposed to constant light (ND-LL); rats fed a high fat diet, and exposed to standard light-dark cycle (HFD-LD); and rats on a high fat diet, and exposed to constant light (HFD-LL). Body weight, hepatic pathophysiology, gut microbiota, and short/medium chain fatty acids in colon contents, serum lipopolysaccharide (LPS), and liver LPS-binding protein (LBP) mRNA expression were documented post intervention and compared among groups.

Result: In normal chow fed groups, rats exposed to constant light displayed glucose abnormalities and dyslipidemia. In HFD-fed rats, constant light exposure exacerbated glucose abnormalities, insulin resistance, inflammation, and liver steatohepatitis. Constant light exposure altered composition of gut microbiota in both normal chow and HFD fed rats. Compared with HFD-LD group, HFD-LL rats displayed less Butyricicoccus, Clostridium, and Turicibacter, butyrate levels in colon contents, decreased colon expression of occludin-1 and zonula occluden−1 (ZO-1), and increased serum LPS and liver LBP mRNA expression.

Conclusion: Constant light exposure impacts gut microbiota and its metabolic products, impairs gut barrier function and gut-liver axis, promotes NAFLD/NASH progression in HFD rats.
 
  Address  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1664-302X ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 3099  
Permanent link to this record
 

 
Author Zhang, H.; Yan, K.; Sui, L.; Nie, J.; Cui, K.; Liu, J.; Zhang, H.; Yang, X.; Lu, K.; Liang, X. url  doi
openurl 
  Title Constant light exposure causes oocyte meiotic defects and quality deterioration in mice Type Journal Article
  Year 2020 Publication Environmental Pollution Abbreviated Journal Environmental Pollution  
  Volume in press Issue Pages 115467  
  Keywords (up) Animals  
  Abstract Artificial light at night (ALAN) exposes us to prolonged illumination, that adversely affects female reproduction. However, it remains to be clarified how prolonged light exposure affects oocyte meiotic maturation and quality. To this end, we exposed female mice to a constant light (CL) of 250 lux for different durations. Our findings showed that CL exposure for 7 weeks reduced the oocyte maturation rate. Meanwhile, CL exposure caused greater abnormalities in spindle assembly and chromosome alignment and a higher rate of oocyte aneuploidy than the regular light dark cycle. CL exposure also induced oxidative stress and caused mitochondrial dysfunction, which resulted in oocyte apoptosis and autophagy. Notably, our results showed that CL exposure reduced the levels of α-tubulin acetylation, DNA methylation at 5mC, RNA methylation at m6A and histone methylation at H3K4me2 but increased the levels of histone methylation at H3K27me2 in oocytes. In summary, our findings demonstrate that constant bright light exposure causes oocyte meiotic defects and reduces cytoplasmic quality. These results extend the current understanding of ALAN-mediated defects in female reproduction.  
  Address  
  Corporate Author Thesis  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0269-7491 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 3101  
Permanent link to this record
 

 
Author Chukwu A. T.; Samaila N.; Okrikata E. url  doi
openurl 
  Title Flight to Light Response of Red Pumpkin Beetle (Aulacophora africana Weise) to Differently Coloured Light-emitting Diode and Incandescent Bulb Lights Type Journal Article
  Year 2019 Publication Advanced Journal of Graduate Research Abbreviated Journal Adv. J. Grad. Res.  
  Volume 7 Issue 1 Pages 64-69  
  Keywords (up) Animals  
  Abstract Red pumpkin beetle (Aulacophora africana Weise) is an important defoliator and vector of pathogens to its numerous crop hosts. Control had largely been by synthetic insecticides with their attendant consequences on man and the environment thus necessitating scientific studies on environmental-friendly management strategies. The experiment was conducted in the Research Farm of Federal University Wukari in the month of May 2019 with the aim of evaluating the attractiveness of A. africana to Light-emitting diode (LED) and Incandescent Light bulb colours. Five colours (red, yellow, green, blue and white) were used for the study. Each colour light was properly projected on 2 metre vertical screen (made of white polyethene) placed one meter above the ground. A setup without bulb served as the control. The light traps were arranged in a completely randomized design (CRD) in 6 replicates and ran simultaneously for six hours (1800 to 2400hrs). The pumpkin beetles attracted were collected in tubs containing soapy water. A. africana collected were counted and recorded according to bulb type and colour. Samples were identified at the Insect Museum of Ahmadu Bello University, Zaria. Among the Incandescent bulbs, White colour was most attractive to A. africana (4.30±0.38) while red attracted the least (0.71±0.01). Among LED bulbs, Blue was most attractive (3.99±1.01) while Red also attracted the least (0.78±0.03). Overall, LED attracted more pumpkin beetles than Incandescent bulb even though Student Newman Keul’s test indicates that the difference between them was due to random variation (p = 0.16). Correlation and regression analyses indicated increase in insect attraction with increased light intensity. The results, therefore, suggest that white Incandescent or blue LED bulb colours can be incorporated into insecticidal light traps to suppress their population/attract them away from host plants or fixed into ordinary light traps to harvest the insect for scientific studies.  
  Address  
  Corporate Author Thesis Bachelor's thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number UP @ altintas1 @ Serial 3144  
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