1
|
Appenroth D, West AC, Wood SH, Hazlerigg DG. Tanycytes from a bird's eye view: gene expression profiling of the tanycytic region under different seasonal states in the Svalbard ptarmigan. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2024:10.1007/s00359-024-01716-3. [PMID: 39299992 DOI: 10.1007/s00359-024-01716-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2024] [Revised: 09/03/2024] [Accepted: 09/06/2024] [Indexed: 09/22/2024]
Abstract
In mammals and birds, tanycytes are known to regulate thyroid hormone conversion, and this process is central to the control of seasonal reproduction. In mammals, this cell type is also implicated in retinoic acid signalling, neurogenesis, and nutritional gatekeeping, all of which have been linked to hypothalamic regulation of energy metabolism. Less is known about these potential wider roles of tanycytes in birds. To address this gap, we combined LASER capture microdissection and transcriptomics to profile the tanycytic region in male Svalbard ptarmigan, a High Arctic species with photoperiod-dependent seasonal rhythms in reproductive activation and body mass. Short photoperiod (SP) adapted birds were transferred to constant light (LL) to trigger breeding and body mass loss. After five months under LL, the development of photorefractoriness led to spontaneous re-emergence of the winter phenotype, marked by the termination of breeding and gain in body mass. The transfer from SP to LL initiated gene expression changes in both thyroid hormone and retinoic acid pathways, as described in seasonal mammals. Furthermore, transcriptomic signatures of cell differentiation and migration were observed. Comparison to data from Siberian hamsters demonstrated that a photoperiod-dependent re-organisation of the hypothalamic tanycytic region is likely a conserved feature. Conversely, the spontaneous development of photorefractoriness showed a surprisingly small number of genes that reverted in expression level, despite reversal of the reproductive and metabolic phenotype. Our data suggest general conservation of tanycyte biology between photoperiodic birds and mammals and raise questions about the mechanistic origins of the photorefractory state.
Collapse
Affiliation(s)
- Daniel Appenroth
- Arctic Seasonal Timekeeping Initiative (ASTI), Arctic Chronobiology & Physiology, Arctic & Marine Biology, BFE, UiT - Arctic University of Norway, Tromsø, Norway.
| | - Alexander C West
- Arctic Seasonal Timekeeping Initiative (ASTI), Arctic Chronobiology & Physiology, Arctic & Marine Biology, BFE, UiT - Arctic University of Norway, Tromsø, Norway
| | - Shona H Wood
- Arctic Seasonal Timekeeping Initiative (ASTI), Arctic Chronobiology & Physiology, Arctic & Marine Biology, BFE, UiT - Arctic University of Norway, Tromsø, Norway
| | - David G Hazlerigg
- Arctic Seasonal Timekeeping Initiative (ASTI), Arctic Chronobiology & Physiology, Arctic & Marine Biology, BFE, UiT - Arctic University of Norway, Tromsø, Norway
| |
Collapse
|
2
|
Kuzmenko NV, Galagudza MM. Hormonal basis of seasonal metabolic changes in mammalian species. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2024; 142:131-161. [PMID: 39059984 DOI: 10.1016/bs.apcsb.2024.02.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/28/2024]
Abstract
Seasonal changes in external conditions (photoperiod, meteorological conditions, diet) cause adaptive changes in both energy and substrate metabolism in the animals of mammalian species. In summer, long days and a rich diet contribute to relative elevation in the levels of thyroid hormones (TH), but warmer weather lowers their levels. In winter, short days and a poor diet inhibit TH synthesis, but low temperatures increase their secretion. In addition, the results of our meta-analyses revealed a significant role of atmospheric pressure in circannual fluctuations of metabolic parameters in humans. The changes in photoperiod are generally viewed as a major factor contributing to seasonal rhythm regulation However, numerous data show that season-dependent metabolic changes in mammals could be also accounted for by meteorological factors and diet.
Collapse
Affiliation(s)
- N V Kuzmenko
- Department for Experimental Physiology and Pharmacology, Almazov National Medical Research Centre, St. Petersburg, Russia.
| | - M M Galagudza
- Department for Experimental Physiology and Pharmacology, Almazov National Medical Research Centre, St. Petersburg, Russia
| |
Collapse
|
3
|
Navarro-Masip È, Manocchio F, Rodríguez RM, Bravo FI, Torres-Fuentes C, Muguerza B, Aragonès G. Photoperiod-Dependent Effects of Grape-Seed Proanthocyanidins on Adipose Tissue Metabolic Markers in Healthy Rats. Mol Nutr Food Res 2023; 67:e2300035. [PMID: 37423963 DOI: 10.1002/mnfr.202300035] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 04/26/2023] [Indexed: 07/11/2023]
Abstract
SCOPE Variations in photoperiod patterns drive metabolic adaptations in mammals, involving important changes in body weight and adiposity. Moreover, (poly)phenols can help heterotrophs adopt metabolic adaptations to face the upcoming environmental conditions. Particularly, proanthocyanidins from grape-seeds show photoperiod-dependent effects on different metabolic parameters. The present study aims to explore whether grape-seed proanthocyanidin extract (GSPE) consumption differently affects the expression of metabolic markers in WAT (subcutaneous and visceral depots) and BAT in a photoperiod-dependent manner. METHODS AND RESULTS GSPE (25 mg kg-1 day-1 ) is orally administrated for 4 weeks to healthy rats exposed to three photoperiods (L6, L12, and L18). In WAT, GSPE consumption significantly upregulates the expression of lipolytic genes in all photoperiods, being accompanied by increased serum concentrations of glycerol and corticosterone only under the L6 photoperiod. Moreover, adiponectin mRNA levels are significantly upregulated in response to GSPE regardless of the photoperiod, whereas Tnfα and Il6 expression are only downregulated in L6 and L18 photoperiods but not in L12. In BAT, GSPE upregulates Pgc1α expression in all groups, whereas the expression of Pparα is only increased in L18. CONCLUSIONS The results indicate that GSPE modulates the expression of important metabolic markers of WAT and BAT in a photoperiod-dependent manner.
Collapse
Affiliation(s)
- Èlia Navarro-Masip
- Nutrigenomics Research Group, Department of Biochemistry and Biotechnology, Universitat Rovira i Virgili, Tarragona, 43007, Spain
| | - Francesca Manocchio
- Nutrigenomics Research Group, Department of Biochemistry and Biotechnology, Universitat Rovira i Virgili, Tarragona, 43007, Spain
- Institute of Health Research Pere Virgili (IISPV), Tarragona, 43007, Spain
- Center of Environmental, Food and Toxicological Technology (TecnATox), Universitat Rovira i Virgili, Tarragona, 43007, Spain
| | - Romina M Rodríguez
- Nutrigenomics Research Group, Department of Biochemistry and Biotechnology, Universitat Rovira i Virgili, Tarragona, 43007, Spain
| | - Francisca Isabel Bravo
- Nutrigenomics Research Group, Department of Biochemistry and Biotechnology, Universitat Rovira i Virgili, Tarragona, 43007, Spain
| | - Cristina Torres-Fuentes
- Nutrigenomics Research Group, Department of Biochemistry and Biotechnology, Universitat Rovira i Virgili, Tarragona, 43007, Spain
- Institute of Health Research Pere Virgili (IISPV), Tarragona, 43007, Spain
- Center of Environmental, Food and Toxicological Technology (TecnATox), Universitat Rovira i Virgili, Tarragona, 43007, Spain
| | - Begoña Muguerza
- Nutrigenomics Research Group, Department of Biochemistry and Biotechnology, Universitat Rovira i Virgili, Tarragona, 43007, Spain
- Institute of Health Research Pere Virgili (IISPV), Tarragona, 43007, Spain
- Center of Environmental, Food and Toxicological Technology (TecnATox), Universitat Rovira i Virgili, Tarragona, 43007, Spain
| | - Gerard Aragonès
- Nutrigenomics Research Group, Department of Biochemistry and Biotechnology, Universitat Rovira i Virgili, Tarragona, 43007, Spain
- Institute of Health Research Pere Virgili (IISPV), Tarragona, 43007, Spain
- Center of Environmental, Food and Toxicological Technology (TecnATox), Universitat Rovira i Virgili, Tarragona, 43007, Spain
| |
Collapse
|
4
|
Navarro-Masip È, Colom-Pellicer M, Manocchio F, Arola-Arnal A, Bravo FI, Muguerza B, Aragonès G. Grape-Seed Proanthocyanidins Modulate Adipose Tissue Adaptations to Obesity in a Photoperiod-Dependent Manner in Fischer 344 Rats. Nutrients 2023; 15:nu15041037. [PMID: 36839395 PMCID: PMC9967183 DOI: 10.3390/nu15041037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 02/16/2023] [Accepted: 02/17/2023] [Indexed: 02/22/2023] Open
Abstract
Seasonal rhythms drive metabolic adaptations that influence body weight and adiposity. Adipose tissue is a key regulator of energy homeostasis in the organism, and its healthiness is needed to prevent the major consequences of overweight and obesity. In this context, supplementation with proanthocyanidins has been postulated as a potential strategy to prevent the alterations caused by obesity. Moreover, the effects of these (poly)phenols on metabolism are photoperiod dependent. In order to describe the impact of grape-seed proanthocyanidins extract (GSPE) on important markers of adipose tissue functionality under an obesogenic environment, we exposed Fischer 344 rats to three different photoperiods and fed them a cafeteria diet for five weeks. Afterwards, we supplemented them with 25 mg GSPE/kg/day for four weeks. Our results revealed that GSPE supplementation prevented excessive body weight gain under a long photoperiod, which could be explained by increased lipolysis in the adipose tissue. Moreover, cholesterol and non-esterified fatty acids (NEFAs) serum concentrations were restored by GSPE under standard photoperiod. GSPE consumption slightly helped combat the obesity-induced hypertrophy in adipocytes, and adiponectin mRNA levels were upregulated under all photoperiods. Overall, the administration of GSPE helped reduce the impact of obesity in the adipose tissue, depending on the photoperiod at which GSPE was consumed and on the type of adipose depots.
Collapse
|
5
|
Wucher V, Sodaei R, Amador R, Irimia M, Guigó R. Day-night and seasonal variation of human gene expression across tissues. PLoS Biol 2023; 21:e3001986. [PMID: 36745672 PMCID: PMC9934459 DOI: 10.1371/journal.pbio.3001986] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 02/16/2023] [Accepted: 01/03/2023] [Indexed: 02/07/2023] Open
Abstract
Circadian and circannual cycles trigger physiological changes whose reflection on human transcriptomes remains largely uncharted. We used the time and season of death of 932 individuals from GTEx to jointly investigate transcriptomic changes associated with those cycles across multiple tissues. Overall, most variation across tissues during day-night and among seasons was unique to each cycle. Although all tissues remodeled their transcriptomes, brain and gonadal tissues exhibited the highest seasonality, whereas those in the thoracic cavity showed stronger day-night regulation. Core clock genes displayed marked day-night differences across multiple tissues, which were largely conserved in baboon and mouse, but adapted to their nocturnal or diurnal habits. Seasonal variation of expression affected multiple pathways, and it was enriched among genes associated with the immune response, consistent with the seasonality of viral infections. Furthermore, they unveiled cytoarchitectural changes in brain regions. Altogether, our results provide the first combined atlas of how transcriptomes from human tissues adapt to major cycling environmental conditions. This atlas may have multiple applications; for example, drug targets with day-night or seasonal variation in gene expression may benefit from temporally adjusted doses.
Collapse
Affiliation(s)
- Valentin Wucher
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
- MeLiS, SynatAc Team, UCBL1—CNRS UMR5284—Inserm U1314, Lyon, France
- French Reference Center on Paraneoplastic Neurological Syndrome, Hospices Civils de Lyon, Lyon, France
- University of Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | - Reza Sodaei
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Raziel Amador
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Manuel Irimia
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra, Barcelona, Spain
- ICREA, Barcelona, Spain
- * E-mail: (MI); (RG)
| | - Roderic Guigó
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra, Barcelona, Spain
- * E-mail: (MI); (RG)
| |
Collapse
|
6
|
Navarro-Masip È, Caron A, Mulero M, Arola L, Aragonès G. Photoperiodic Remodeling of Adiposity and Energy Metabolism in Non-Human Mammals. Int J Mol Sci 2023; 24:ijms24021008. [PMID: 36674520 PMCID: PMC9865556 DOI: 10.3390/ijms24021008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/01/2023] [Accepted: 01/02/2023] [Indexed: 01/07/2023] Open
Abstract
Energy homeostasis and metabolism in mammals are strongly influenced by seasonal changes. Variations in photoperiod patterns drive adaptations in body weight and adiposity, reflecting changes in the regulation of food intake and energy expenditure. Humans also show distinct patterns of energy balance depending on the season, being more susceptible to gaining weight during a specific time of the year. Changes in body weight are mainly reflected by the adipose tissue, which is a key metabolic tissue and is highly affected by circannual rhythms. Mostly, in summer-like (long-active) photoperiod, adipocytes adopt a rather anabolic profile, more predisposed to store energy, while food intake increases and energy expenditure is reduced. These metabolic adaptations involve molecular modifications, some of which have been studied during the last years and are summarized in this review. In addition, there is a bidirectional relation between obesity and the seasonal responses, with obesity disrupting some of the seasonal responses observed in healthy mammals, and altered seasonality being highly associated with increased risk of developing obesity. This suggests that changes in photoperiod produce important metabolic alterations in healthy organisms. Biological rhythms impact the regulation of metabolism to different extents, some of which are already known, but further research is needed to fully understand the relationship between energy balance and seasonality.
Collapse
Affiliation(s)
- Èlia Navarro-Masip
- Nutrigenomics Research Group, Department of Biochemistry and Biotechnology, Universitat Rovira i Virgili, 43007 Tarragona, Spain
| | - Alexandre Caron
- Faculty of Pharmacy, Université Laval, Québec City, QC G1V 0A6, Canada
| | - Miquel Mulero
- Nutrigenomics Research Group, Department of Biochemistry and Biotechnology, Universitat Rovira i Virgili, 43007 Tarragona, Spain
| | - Lluís Arola
- Nutrigenomics Research Group, Department of Biochemistry and Biotechnology, Universitat Rovira i Virgili, 43007 Tarragona, Spain
| | - Gerard Aragonès
- Nutrigenomics Research Group, Department of Biochemistry and Biotechnology, Universitat Rovira i Virgili, 43007 Tarragona, Spain
- Correspondence:
| |
Collapse
|
7
|
Dardente H, Lomet D, Desmarchais A, Téteau O, Lasserre O, Gonzalez AA, Dubois E, Beltramo M, Elis S. Impact of food restriction on the medio-basal hypothalamus of intact ewes as revealed by a large-scale transcriptomics study. J Neuroendocrinol 2022; 34:e13198. [PMID: 36168278 DOI: 10.1111/jne.13198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 08/25/2022] [Accepted: 08/28/2022] [Indexed: 11/27/2022]
Abstract
In mammals, the medio-basal hypothalamus (MBH) integrates photoperiodic and food-related cues to ensure timely phasing of physiological functions, including seasonal reproduction. The current human epidemics of obesity and associated reproductive disorders exemplifies the tight link between metabolism and reproduction. Yet, how food-related cues impact breeding at the level of the MBH remains unclear. In this respect, the sheep, which is a large diurnal mammal with a marked dual photoperiodic/metabolic control of seasonal breeding, is a relevant model. Here, we present a large-scale study in ewes (n = 120), which investigated the impact of food restriction (FRes) on the MBH transcriptome using unbiased RNAseq, followed by RT-qPCR. Few genes (~100) were impacted by FRes and the transcriptional impact was very modest (<2-fold increase or < 50% decrease for most genes). As anticipated, FRes increased expression of Npy/AgRP/LepR and decreased expression of Pomc/Cartpt, while Kiss1 expression was not impacted. Of particular interest, Eya3, Nmu and Dio2, genes involved in photoperiodic decoding within the MBH, were also affected by FRes. Finally, we also identified a handful of genes not known to be regulated by food-related cues (e.g., RNase6, HspA6, Arrdc2). In conclusion, our transcriptomics study provides insights into the impact of metabolism on the MBH in sheep, which may be relevant to human, and identifies possible molecular links between metabolism and (seasonal) reproduction.
Collapse
Affiliation(s)
- Hugues Dardente
- CNRS, IFCE, INRAE, Université de Tours, PRC, Nouzilly, France
| | - Didier Lomet
- CNRS, IFCE, INRAE, Université de Tours, PRC, Nouzilly, France
| | | | - Ophélie Téteau
- CNRS, IFCE, INRAE, Université de Tours, PRC, Nouzilly, France
| | | | - Anne-Alicia Gonzalez
- MGX-Montpellier GenomiX, Université Montpellier, CNRS, INSERM, Montpellier, France
| | - Emeric Dubois
- MGX-Montpellier GenomiX, Université Montpellier, CNRS, INSERM, Montpellier, France
| | | | - Sébastien Elis
- CNRS, IFCE, INRAE, Université de Tours, PRC, Nouzilly, France
| |
Collapse
|
8
|
The Effect of Leptin on the Blood Hormonal Profile (Cortisol, Insulin, Thyroid Hormones) of the Ewe in Acute Inflammation in Two Different Photoperiodical Conditions. Int J Mol Sci 2022; 23:ijms23158109. [PMID: 35897684 PMCID: PMC9331064 DOI: 10.3390/ijms23158109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 07/20/2022] [Accepted: 07/21/2022] [Indexed: 01/25/2023] Open
Abstract
As a day animal with sensitivity to inflammation similar to that of humans, the sheep may highly outperform the rodent model in inflammation studies. Additionally, seasonality makes sheep an interesting model in endocrinology research. Although there are studies concerning inflammation’s influence on leptin secretion and vice versa, a ewe model, with its possible ‘long-day leptin resistance’, is still not examined enough. The present study aimed to examine whether leptin may modulate an acute inflammation influence on plasma hormones in two photoperiodical conditions. The experiment was conducted on 48 ewes divided into four groups (control, lipopolysaccharide (LPS), leptin, LPS + leptin) during short and long days. Blood sampling started 1 hour before and continued 3 h after LPS/saline administration for further hormonal analysis. The results showed that the photoperiod is one of the main factors influencing the basal concentrations of several hormones with higher values of leptin, insulin and thyroid hormones during long days. Additionally, the acute inflammation effect on cortisol, insulin and thyroid hormones was photoperiod-dependent. The endotoxemia may also exert an influence on leptin concentration regardless of season. The effects of leptin alone on hormone blood concentrations are rather limited; however, leptin can modulate the LPS influence on insulin or thyroxine in a photoperiod-dependent way.
Collapse
|
9
|
|
10
|
Wucher V, Sodaei R, Amador R, Irimia M, Guigó R. Day-night and seasonal variation of human gene expression across tissues. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2022:2021.02.28.433266. [PMID: 33688644 PMCID: PMC7941615 DOI: 10.1101/2021.02.28.433266] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Circadian and circannual cycles trigger physiological changes whose reflection on human transcriptomes remains largely uncharted. We used the time and season of death of 932 individuals from GTEx to jointly investigate transcriptomic changes associated with those cycles across multiple tissues. Overall, most variation across tissues during day-night and among seasons was unique to each cycle. Although all tissues remodeled their transcriptomes, brain and gonadal tissues exhibited the highest seasonality, whereas those in the thoracic cavity showed stronger day-night regulation. Core clock genes displayed marked day-night differences across multiple tissues, which were largely conserved in baboon and mouse, but adapted to their nocturnal or diurnal habits. Seasonal variation of expression affected multiple pathways and it was enriched among genes associated with the immune response, consistent with the seasonality of viral infections. Furthermore, they unveiled cytoarchitectural changes in brain regions. Altogether, our results provide the first combined atlas of how transcriptomes from human tissues adapt to major cycling environmental conditions.
Collapse
Affiliation(s)
- Valentin Wucher
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
- NeuroMyogene Institute, SynatAc Team, INSERM U1217/UMR CNRS 5310, Lyon, France
- French Reference Center on Paraneoplastic Neurological Syndrome, Hospices Civils de Lyon, Lyon, France
- University of Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | - Reza Sodaei
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Raziel Amador
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Manuel Irimia
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra, Barcelona, Spain
- ICREA, Barcelona, Spain
| | - Roderic Guigó
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra, Barcelona, Spain
| |
Collapse
|
11
|
Little AG. Thyroid hormone regulation of thermal acclimation in ectotherms: Physiological mechanisms and ecoevolutionary implications. Mol Cell Endocrinol 2021; 530:111285. [PMID: 33891994 DOI: 10.1016/j.mce.2021.111285] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 02/07/2021] [Accepted: 04/12/2021] [Indexed: 02/07/2023]
Abstract
The pathways that regulate adaptive thermal plasticity in ectothermic vertebrates have received little attention relative to those in birds and mammals. However, there is increasing evidence that thyroid hormone represents a critical regulator of thermal plasticity in both ectothermic and endothermic vertebrates. In this review, I summarize the evidence for thyroid hormone-mediated thermal compensation responses in ectothermic vertebrates, with specific focus on effects on the whole animal, skeletal muscle, and cardiac muscle. Interestingly, these effects can differ wildly between focal tissues and species. I move on to discuss what the role of thyroid hormone in ectotherm thermal plasticity can reveal about stressor interactions and central vs. peripheral levels of thyroid hormone regulation. Lastly, I focus on the conserved nature of thyroid hormone signaling in animal thermal responses, with specific reference to the ectotherm → endotherm spectrum. I use this framework to highlight research avenues that will further resolve the evolutionary trajectory of thyroid hormone actions across animals. I hope to emphasize what thyroid hormone-mediated cold acclimation in a 3 cm fish can contribute to ongoing debates surrounding the impacts of stressor interactions, the potential costs of plasticity, the evolution of endothermy, and the impacts of global change.
Collapse
Affiliation(s)
- A G Little
- Department of Biology, Queen's University, Kingston, Ontario, K7L 3N6, Canada.
| |
Collapse
|
12
|
Charlot A, Hutt F, Sabatier E, Zoll J. Beneficial Effects of Early Time-Restricted Feeding on Metabolic Diseases: Importance of Aligning Food Habits with the Circadian Clock. Nutrients 2021; 13:nu13051405. [PMID: 33921979 PMCID: PMC8143522 DOI: 10.3390/nu13051405] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 04/17/2021] [Accepted: 04/20/2021] [Indexed: 12/11/2022] Open
Abstract
The importance of metabolic health is a major societal concern due to the increasing prevalence of metabolic diseases such as obesity, diabetes, and various cardiovascular diseases. The circadian clock is clearly implicated in the development of these metabolic diseases. Indeed, it regulates physiological processes by hormone modulation, thus helping the body to perform them at the ideal time of day. Since the industrial revolution, the actions and rhythms of everyday life have been modified and are characterized by changes in sleep pattern, work schedules, and eating habits. These modifications have in turn lead to night shift, social jetlag, late-night eating, and meal skipping, a group of customs that causes circadian rhythm disruption and leads to an increase in metabolic risks. Intermittent fasting, especially the time-restricted eating, proposes a solution: restraining the feeding window from 6 to 10 h per day to match it with the circadian clock. This approach seems to improve metabolic health markers and could be a therapeutic solution to fight against metabolic diseases. This review summarizes the importance of matching life habits with circadian rhythms for metabolic health and assesses the advantages and limits of the application of time-restricted fasting with the objective of treating and preventing metabolic diseases.
Collapse
|
13
|
Frare C, Drew KL. Seasonal changes in adenosine kinase in tanycytes of the Arctic ground squirrel (Urocitellus parryii). J Chem Neuroanat 2021; 113:101920. [PMID: 33515665 PMCID: PMC8091519 DOI: 10.1016/j.jchemneu.2021.101920] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 12/29/2020] [Accepted: 01/18/2021] [Indexed: 10/22/2022]
Abstract
Hibernation is a seasonal strategy to conserve energy, characterized by modified thermoregulation, an increase in sleep pressure and drastic metabolic changes. Glial cells such as astrocytes and tanycytes are the brain metabolic sensors, but it remains unknown whether they contribute to seasonal expression of hibernation. The onset of hibernation is controlled by an undefined endogenous circannual rhythm in which adenosine plays a role through the activation of the A1 adenosine receptor (A1AR). Seasonal changes in brain levels of adenosine may contribute to an increase in A1AR sensitivity leading to the onset of hibernation. The primary regulator of extracellular adenosine concentration is adenosine kinase, which is located in astrocytes. Using immunohistochemistry to localize and quantify adenosine kinase in Arctic ground squirrels' brain collected during different seasons, we report lower expression of adenosine kinase in the third ventricle tanycytes in winter compared to summer; a similar change was not seen in astrocytes. Moreover, for the first time, we describe adenosine kinase expression in tanycyte cell bodies in the hypothalamus and in the area postrema, both brain regions involved in energy homeostasis. Next we describe seasonal changes in tanycyte morphology in the hypothalamus. Although still speculative, our findings contribute to a model whereby adenosine kinase in tanycytes regulates seasonal changes in extracellular concentration of adenosine underling the seasonal expression of hibernation.
Collapse
Affiliation(s)
- C Frare
- Department of Chemistry and Biochemistry, University of Alaska Fairbanks, 900 Yukon Drive Rm. 194, Fairbanks, AK 99775-6160, USA; Institute of Arctic Biology, Center for Transformative Research in Metabolism, University of Alaska Fairbanks, 2140 Koyukuk Drive, Fairbanks, AK 99775-7000 USA
| | - K L Drew
- Department of Chemistry and Biochemistry, University of Alaska Fairbanks, 900 Yukon Drive Rm. 194, Fairbanks, AK 99775-6160, USA; Institute of Arctic Biology, Center for Transformative Research in Metabolism, University of Alaska Fairbanks, 2140 Koyukuk Drive, Fairbanks, AK 99775-7000 USA.
| |
Collapse
|
14
|
Przybylska-Piech AS, Wojciechowski MS, Jefimow M. Polymorphism of winter phenotype in Siberian hamster: consecutive litters do not differ in photoresponsiveness but prolonged acclimation to long photoperiod inhibits winter molt. Front Zool 2021; 18:11. [PMID: 33731152 PMCID: PMC7971963 DOI: 10.1186/s12983-021-00391-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 02/21/2021] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND The theory of delayed life history effects assumes that phenotype of adult individual results from environmental conditions experienced at birth and as juvenile. In seasonal environments, being born late in the reproductive season affects timing of puberty, body condition, longevity, and fitness. We hypothesized that late-born individuals are more prone to respond to short photoperiod (SP) than early born ones. We used Siberian hamsters Phodopus sungorus, a model species characterized by high polymorphism of winter phenotype. We experimentally distinguished the effect of litter order (first or third) from the effect of exposure to long photoperiod (LP) before winter (3 months or 5 months) by manipulating the duration of LP acclimation in both litters. We predicted that, irrespective of the litter order, individuals exposed to long photoperiod for a short time have less time to gather energy resources and consequently are more prone to developing energy-conserving phenotypes. To assess effect of litter order, duration of acclimation to long days, and phenotype on basal cost of living we measured basal metabolic rate (BMR) of hamsters. RESULTS Individuals born in third litters had faster growth rates and were bigger than individuals from first litters, but these differences vanished before transfer to SP. Litter order or duration of LP acclimation had no effects on torpor use or seasonal body mass changes, but prolonged acclimation to LP inhibited winter molting both in first and third litters. Moreover, individuals that did not molt had significantly higher BMR in SP than those which molted to white fur. Although one phenotype usually predominated within a litter, littermates were often heterogeneous. We also found that over 10% of individuals presented late response to short photoperiod. CONCLUSIONS Our data indicate that duration of postnatal exposure to LP may define propensity to photoresponsiveness, regardless of the litter in which animal was born. Existence of littermates presenting different phenotypes suggests a prudent reproductive strategy of investing into offspring of varied phenotypes, that might be favored depending on environmental conditions. This strategy could have evolved in response to living in stochastic environment.
Collapse
Affiliation(s)
- Anna S Przybylska-Piech
- Department of Vertebrate Zoology and Ecology, Nicolaus Copernicus University, Toruń, Poland.
| | - Michał S Wojciechowski
- Department of Vertebrate Zoology and Ecology, Nicolaus Copernicus University, Toruń, Poland
| | - Małgorzata Jefimow
- Department of Animal Physiology and Neurobiology, Nicolaus Copernicus University, Toruń, Poland
| |
Collapse
|
15
|
Dardente H, Migaud M. Thyroid hormone and hypothalamic stem cells in seasonal functions. VITAMINS AND HORMONES 2021; 116:91-131. [PMID: 33752829 DOI: 10.1016/bs.vh.2021.02.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Seasonal rhythms are a pervasive feature of most living organisms, which underlie yearly timeliness in breeding, migration, hibernation or weight gain and loss. To achieve this, organisms have developed inner timing devices (circannual clocks) that endow them with the ability to predict then anticipate changes to come, usually using daylength as the proximate cue. In Vertebrates, daylength interpretation involves photoperiodic control of TSH production by the pars tuberalis (PT) of the pituitary, which governs a seasonal switch in thyroid hormone (TH) availability in the neighboring hypothalamus. Tanycytes, specialized glial cells lining the third ventricle (3V), are responsible for this TH output through the opposite, PT-TSH-driven, seasonal control of deiodinases 2/3 (Dio 2/3). Tanycytes comprise a photoperiod-sensitive stem cell niche and TH is known to play major roles in cell proliferation and differentiation, which suggests that seasonal control of tanycyte proliferation may be involved in the photoperiodic synchronization of seasonal rhythms. Here we review our current knowledge of the molecular and neuroendocrine pathway linking photoperiodic information to seasonal changes in physiological functions and discuss the potential implication of tanycytes, TH and cell proliferation in seasonal timing.
Collapse
Affiliation(s)
- Hugues Dardente
- PRC, INRAE, CNRS, IFCE, Université de Tours, Nouzilly, France.
| | - Martine Migaud
- PRC, INRAE, CNRS, IFCE, Université de Tours, Nouzilly, France
| |
Collapse
|
16
|
Regional Differences in Height, Weight, and Body Composition may Result from Photoperiodic Responses: An Ecological Analysis of Japanese Children and Adolescents. J Circadian Rhythms 2021; 19:3. [PMID: 33664773 PMCID: PMC7908924 DOI: 10.5334/jcr.198] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This ecological study examined whether geographical differences in the physique of Japanese children and adolescents can be explained from the perspective of photoperiodicity induced by effective day length (light duration exceeding a certain threshold of illuminance) using prefecture-level anatomical data and Mesh Climatic Data. Multiple regression analysis for height prediction demonstrated that when controlled by weight, effective day lengths of the longest and shortest months were inversely correlated with height distribution. Conversely, for weight prediction, when controlled by height, the effective day lengths of the longest and shortest months were positively correlated with weight distribution. The regression coefficients were greater for the effective day length of the shortest month in both height and weight prediction. This phenomenon where the same two explanatory variables are negatively correlated with height and positively correlated with weight in a significant manner is rare, and there may be no physiological interpretation of this phenomenon other than one based on changes in thyroid hormone signaling. These distribution characteristics are common to the photoperiodicity by which seasonal breeding vertebrates reciprocally switch thyroid hormone signaling according to prior photoperiodic history through epigenetic functions. From these perspectives, thyroid hormone signaling in a certain region was assumed to be activated in summer according to the prior shorter winter day length and inactivated in winter according to the prior longer summer day length. Regarding the prevalence of obesity, the coexistence of longer summer and winter day lengths was thought to set body composition to be short and fat in early adolescence.
Collapse
|
17
|
Kuzmenko NV, Tsyrlin VA, Pliss MG, Galagudza MM. Seasonal variations in levels of human thyroid-stimulating hormone and thyroid hormones: a meta-analysis. Chronobiol Int 2021; 38:301-317. [PMID: 33535823 DOI: 10.1080/07420528.2020.1865394] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Seasonal dynamics in biological functions of mammals is regulated by melatonin-mediated circannual fluctuations in the secretion of thyroid-stimulating hormone (TSH) and thyroid hormones. Most anatomical and molecular structures responsive to photoperiod and melatonin secretion changes and the associated receptors are preserved in modern humans. This work aimed to determine the seasonal dynamics of TSH and thyroid hormone levels (total triiodothyronine (T3), free triiodothyronine (FT3), thyroxine (T4), free thyroxine (FT4) and to investigate the dependence of these variations on gender, age and amplitude of meteorological fluctuations. A meta-analysis of 13 panel and 7 cross-sectional studies was performed using Review Manager 5.3 (Cochrane Library). We found that circulating TSH levels were higher in winter than in other seasons, and FT4 levels were higher in autumn than in winter. T4 level had no pronounced seasonal dynamics. The level of circulating T3 was significantly higher in winter than in summer and FT3 levels were lower in summer than in autumn and spring. In addition, analysis of TSH seasonal dynamics (winter vs summer) accounting for gender differences showed pronounced increases in TSH levels during winter in women, but not in men; and also significant increases in FT4 levels during summer in men, but not in women. Seasonal dynamics of FT3 and T4 did not depend on gender. Seasonal dynamics of TSH did not change with respect to age. We also found that the extent of the seasonal dynamics of TSH is influenced by the extent of the annual dynamics of the partial density of oxygen in the air, as well as the magnitude of the annual dynamic of meteorological factors that determine it (atmospheric pressure and relative humidity).
Collapse
Affiliation(s)
- N V Kuzmenko
- Department for Experimental Physiology and Pharmacology, Almazov National Medical Research Centre, St. Petersburg, Russia.,Laboratory of Byophysics of Blood Circulation, First Pavlov State Medical University of St. Petersburg, St. Petersburg, Russia
| | - V A Tsyrlin
- Department for Experimental Physiology and Pharmacology, Almazov National Medical Research Centre, St. Petersburg, Russia
| | - M G Pliss
- Department for Experimental Physiology and Pharmacology, Almazov National Medical Research Centre, St. Petersburg, Russia.,Laboratory of Byophysics of Blood Circulation, First Pavlov State Medical University of St. Petersburg, St. Petersburg, Russia
| | - M M Galagudza
- Department for Experimental Physiology and Pharmacology, Almazov National Medical Research Centre, St. Petersburg, Russia
| |
Collapse
|
18
|
Moreno JP, Crowley SJ, Alfano CA, Thompson D. Physiological mechanisms underlying children's circannual growth patterns and their contributions to the obesity epidemic in elementary school age children. Obes Rev 2020; 21:e12973. [PMID: 31737994 PMCID: PMC7002188 DOI: 10.1111/obr.12973] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 10/18/2019] [Accepted: 10/18/2019] [Indexed: 12/20/2022]
Abstract
Several studies since the 1990s have demonstrated that children increase their body mass index at a faster rate during summer months compared with the school year, leading some to conclude that the out-of-school summer environment is responsible. Other studies, however, have suggested that seasonality may play a role in children's height and weight changes across the year. This article reviews evidence for seasonal differences in the rate of children's height and weight gain and proposes potential physiological mechanisms that may explain these seasonal variations.
Collapse
Affiliation(s)
- Jennette P Moreno
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | - Stephanie J Crowley
- Biological Rhythm Research Laboratory, Department of Psychiatry and Behavioral Sciences, Rush University Medical Center, Chicago, Illinois
| | - Candice A Alfano
- Sleep and Anxiety Center of Houston (SACH), Department of Psychology, University of Houston, Houston, Texas
| | - Debbe Thompson
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| |
Collapse
|
19
|
Scalf CS, Chariker JH, Rouchka EC, Ashley NT. Transcriptomic analysis of immune response to bacterial lipopolysaccharide in zebra finch (Taeniopygia guttata). BMC Genomics 2019; 20:647. [PMID: 31412766 PMCID: PMC6693190 DOI: 10.1186/s12864-019-6016-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 08/05/2019] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Despite the convergence of rapid technological advances in genomics and the maturing field of ecoimmunology, our understanding of the genes that regulate immunity in wild populations is still nascent. Previous work to assess immune function has relied upon relatively crude measures of immunocompetence. However, with next-generation RNA-sequencing, it is now possible to create a profile of gene expression in response to an immune challenge. In this study, captive zebra finch (Taeniopygia guttata; adult males) were challenged with bacterial lipopolysaccharide (LPS) or vehicle to stimulate the innate immune system. 2 hours after injection, birds were euthanized and hypothalami, spleen, and red blood cells (RBCs) were collected. Taking advantage of the fully sequenced genome of zebra finch, total RNA was isolated, sequenced, and partially annotated in these tissue/cells. RESULTS In hypothalamus, there were 707 significantly upregulated transcripts, as well as 564 and 144 in the spleen and RBCs, respectively, relative to controls. Also, 155 transcripts in the hypothalamus, 606 in the spleen, and 61 in the RBCs were significantly downregulated. More specifically, a number of immunity-related transcripts (e.g., IL-1β, RSAD2, SOCS3) were upregulated among tissues/cells. Additionally, transcripts involved in metabolic processes (APOD, LRAT, RBP4) were downregulated. CONCLUSIONS These results suggest a potential trade-off in expression of genes that regulate immunity and metabolism in birds challenged with LPS. This finding is consistent with a hypothermic response to LPS treatment in small birds. Unlike mammals, birds have nucleated RBCs, and these results support a novel transcriptomic response of avian RBCs to immune challenge.
Collapse
Affiliation(s)
- Cassandra S Scalf
- Department of Biology, Western Kentucky University, Bowling Green, KY, 42101-1800, USA
| | - Julia H Chariker
- Department of Neuroscience Training, University of Louisville, Louisville, KY, 40292, USA
| | - Eric C Rouchka
- Department of Computer Engineering and Computer Science, University of Louisville, Louisville, KY, 40292, USA
| | - Noah T Ashley
- Department of Biology, Western Kentucky University, Bowling Green, KY, 42101-1800, USA.
| |
Collapse
|
20
|
Gibert-Ramos A, Ibars M, Salvadó MJ, Crescenti A. Response to the photoperiod in the white and brown adipose tissues of Fischer 344 rats fed a standard or cafeteria diet. J Nutr Biochem 2019; 70:82-90. [DOI: 10.1016/j.jnutbio.2019.04.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 03/24/2019] [Accepted: 04/25/2019] [Indexed: 01/30/2023]
|
21
|
Lewis JE, Ebling FJP, Samms RJ, Tsintzas K. Going Back to the Biology of FGF21: New Insights. Trends Endocrinol Metab 2019; 30:491-504. [PMID: 31248786 DOI: 10.1016/j.tem.2019.05.007] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 05/29/2019] [Accepted: 05/30/2019] [Indexed: 12/17/2022]
Abstract
Fibroblast growth factor 21 (FGF21) is a protein highly synthesized in the liver that exerts paracrine and endocrine control of many aspects of energy homeostasis in multiple tissues. In preclinical models of obesity and type 2 diabetes, treatment with FGF21 improves glucose homeostasis and promotes weight loss, and, as a result, FGF21 has attracted considerable attention as a therapeutic agent for the treatment of metabolic syndrome in humans. An improved understanding of the biological role of FGF21 may help to explain why its therapeutic potential in humans has not been fully realized. This review will cover the complexities in FGF21 biology in rodents and humans, with emphasis on its role in protection from central and peripheral facets of obesity.
Collapse
Affiliation(s)
- Jo E Lewis
- Institute of Metabolic Sciences and MRC-Metabolic Diseases Unit, University of Cambridge, Cambridge, CB0 0QQ, UK
| | - Francis J P Ebling
- MRC-ARUK Centre for Musculoskeletal Ageing Research, School of Life Sciences, University of Nottingham Medical School, Queen's Medical Centre, Nottingham, NG7 2UH, UK
| | | | - Kostas Tsintzas
- MRC-ARUK Centre for Musculoskeletal Ageing Research, School of Life Sciences, University of Nottingham Medical School, Queen's Medical Centre, Nottingham, NG7 2UH, UK.
| |
Collapse
|
22
|
Bao R, Onishi KG, Tolla E, Ebling FJP, Lewis JE, Anderson RL, Barrett P, Prendergast BJ, Stevenson TJ. Genome sequencing and transcriptome analyses of the Siberian hamster hypothalamus identify mechanisms for seasonal energy balance. Proc Natl Acad Sci U S A 2019; 116:13116-13121. [PMID: 31189592 PMCID: PMC6600942 DOI: 10.1073/pnas.1902896116] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Synthesis of triiodothyronine (T3) in the hypothalamus induces marked seasonal neuromorphology changes across taxa. How species-specific responses to T3 signaling in the CNS drive annual changes in body weight and energy balance remains uncharacterized. These experiments sequenced and annotated the Siberian hamster (Phodopus sungorus) genome, a model organism for seasonal physiology research, to facilitate the dissection of T3-dependent molecular mechanisms that govern predictable, robust, and long-term changes in body weight. Examination of the Phodopus genome, in combination with transcriptome sequencing of the hamster diencephalon under winter and summer conditions, and in vivo-targeted expression analyses confirmed that proopiomelanocortin (pomc) is a primary genomic target for the long-term T3-dependent regulation of body weight. Further in silico analyses of pomc promoter sequences revealed that thyroid hormone receptor 1β-binding motif insertions have evolved in several genera of the Cricetidae family of rodents. Finally, experimental manipulation of food availability confirmed that hypothalamic pomc mRNA expression is dependent on longer-term photoperiod cues and is unresponsive to acute, short-term food availability. These observations suggest that species-specific responses to hypothalamic T3, driven in part by the receptor-binding motif insertions in some cricetid genomes, contribute critically to the long-term regulation of energy balance and the underlying physiological and behavioral adaptations associated with the seasonal organization of behavior.
Collapse
Affiliation(s)
- Riyue Bao
- Center for Research Informatics, University of Chicago, Chicago, IL 60637
- Department of Pediatrics, University of Chicago, Chicago, IL 60637
| | - Kenneth G Onishi
- Institute for Mind and Biology, University of Chicago, Chicago, IL 60637
| | - Elisabetta Tolla
- Institute for Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow G61 1QH, United Kingdom
| | - Fran J P Ebling
- School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, United Kingdom
| | - Jo E Lewis
- Institute of Metabolic Sciences, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Richard L Anderson
- Rowett Institute, University of Aberdeen, Aberdeen AB25 2ZD, United Kingdom
| | - Perry Barrett
- Rowett Institute, University of Aberdeen, Aberdeen AB25 2ZD, United Kingdom
| | - Brian J Prendergast
- Institute for Mind and Biology, University of Chicago, Chicago, IL 60637
- Department of Psychology, University of Chicago, Chicago, IL 60637
| | - Tyler J Stevenson
- Institute for Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow G61 1QH, United Kingdom;
| |
Collapse
|
23
|
Verma R, Haldar C. Expression of receptors for melatonin (MT1), thyroid hormone (TR-α), deiodinase (Dio-2), glucose transporters (GLUT-1 &4) and its relation with splenic cell survival (Bcl-2) of golden hamster, Mesocricetus auratus. BIOL RHYTHM RES 2019. [DOI: 10.1080/09291016.2018.1464632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Rakesh Verma
- Department of Zoology, Banaras Hindu University, Varanasi, India
| | - Chandana Haldar
- Department of Zoology, Banaras Hindu University, Varanasi, India
| |
Collapse
|
24
|
Day length may make geographical difference in body size and proportions: An ecological analysis of Japanese children and adolescents. PLoS One 2019; 14:e0210265. [PMID: 30668608 PMCID: PMC6342304 DOI: 10.1371/journal.pone.0210265] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 12/19/2018] [Indexed: 01/28/2023] Open
Abstract
There is a north-south gradient in the body heights of Japanese children. A hypothesis had previously been proposed that differences in thyroid hormone activity induced by geographical differences in effective day length (duration of photoperiod exceeding a predetermined light intensity) might cause the differences in height. If thyroid hormone is involved, the effect should extend to body weight. This study examined whether geographical differences in body height and weight can be explained in terms of thyroid hormone activity induced by geographical differences in the photoperiodic environment using prefecture-level anatomical data and Japanese Mesh Climatic Data. Multiple regression analysis demonstrated that the combination of effective day length and weight was statistically significant as a predictor of height. Controlling for body weight revealed that effective day length was inversely correlated with height. Multiple regression analysis revealed that a combination of effective day length and height was statistically significant as a predictor of weight. Controlling for height demonstrated that effective day length was positively correlated with weight. Assuming an inverse correlation between effective day length and thyroid hormone activity, these results appear to show that short day-length will increase the activity of thyroid hormone and contribute to increasing height, but will inhibit weight gain; in contrast, long day-length will decrease the activity of thyroid hormone and contribute to increasing weight but will inhibit height gain. Geographical differences in height, and weight, and part of the prevalence of obesity in Japanese children and early adolescents may be explained by geographical differences in effective day length.
Collapse
|
25
|
Helfer G, Wu QF. Chemerin: a multifaceted adipokine involved in metabolic disorders. J Endocrinol 2018; 238:R79-R94. [PMID: 29848608 PMCID: PMC6026924 DOI: 10.1530/joe-18-0174] [Citation(s) in RCA: 195] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 05/30/2018] [Indexed: 12/12/2022]
Abstract
Metabolic syndrome is a global public health problem and predisposes individuals to obesity, diabetes and cardiovascular disease. Although the underlying mechanisms remain to be elucidated, accumulating evidence has uncovered a critical role of adipokines. Chemerin, encoded by the gene Rarres2, is a newly discovered adipokine involved in inflammation, adipogenesis, angiogenesis and energy metabolism. In humans, local and circulating levels of chemerin are positively correlated with BMI and obesity-related biomarkers. In this review, we discuss both peripheral and central roles of chemerin in regulating body metabolism. In general, chemerin is upregulated in obese and diabetic animals. Previous studies by gain or loss of function show an association of chemerin with adipogenesis, glucose homeostasis, food intake and body weight. In the brain, the hypothalamus integrates peripheral afferent signals including adipokines to regulate appetite and energy homeostasis. Chemerin increases food intake in seasonal animals by acting on hypothalamic stem cells, the tanycytes. In peripheral tissues, chemerin increases cell expansion, inflammation and angiogenesis in adipose tissue, collectively resulting in adiposity. While chemerin signalling enhances insulin secretion from pancreatic islets, contradictory results have been reported on how chemerin links to obesity and insulin resistance. Given the association of chemerin with obesity comorbidities in humans, advances in translational research targeting chemerin are expected to mitigate metabolic disorders. Together, the exciting findings gathered in the last decade clearly indicate a crucial multifaceted role for chemerin in the regulation of energy balance, making it a promising candidate for urgently needed pharmacological treatment strategies for obesity.
Collapse
Affiliation(s)
- Gisela Helfer
- School of Chemistry and BiosciencesUniversity of Bradford, Bradford, UK
| | - Qing-Feng Wu
- State Key Laboratory of Molecular Development BiologyInstitute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
- Correspondence should be addressed to Q-F Wu:
| |
Collapse
|
26
|
Ebling FJP, Lewis JE. Tanycytes and hypothalamic control of energy metabolism. Glia 2018; 66:1176-1184. [DOI: 10.1002/glia.23303] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 12/21/2017] [Accepted: 01/23/2018] [Indexed: 01/15/2023]
Affiliation(s)
- Francis J. P. Ebling
- School of Life Sciences; University of Nottingham Medical School, Queen's Medical Centre; Nottingham NG7 2UH United Kingdom
| | - Jo E. Lewis
- School of Life Sciences; University of Nottingham Medical School, Queen's Medical Centre; Nottingham NG7 2UH United Kingdom
| |
Collapse
|
27
|
Abstract
Importance of the neuroendocrine brain for health and happiness has become clear since the 1960s. Foundations laid 100 years ago culminated in Geoffrey W Harris's model of control by the brain of secretion of anterior and posterior pituitary gland hormones through, respectively, releasing factors secreted into the hypothalamic-hypophysial portal system, and directly from axon terminals into the systemic circulation. Confirmation, expansion and deepening of knowledge and understanding have followed increasingly sophisticated technology. This allowed chemical characterisation of the posterior pituitary hormones, oxytocin and vasopressin, the releasing factors, their receptors and genes, location of the neurosecretory neurons in the hypothalamus, and how their activity is controlled, including by neural and hormonal feedback, and how hormone rhythms are generated. Wider roles of these neurons and their peptides in the brain are now recognised: in reproductive and social behaviours, emotions and appetite. Plasticity and epigenetic programming of neuroendocrine systems have emerged as important features.
Collapse
Affiliation(s)
- John A. Russell
- Professor Emeritus, Edinburgh Medical School: Biomedical Sciences, College of Medicine and Veterinary Medicine, University of Edinburgh, UK
| |
Collapse
|
28
|
Stevenson TJ, Alward BA, Ebling FJP, Fernald RD, Kelly A, Ophir AG. The Value of Comparative Animal Research: Krogh's Principle Facilitates Scientific Discoveries. ACTA ACUST UNITED AC 2017; 5:118-125. [PMID: 32743064 DOI: 10.1177/2372732217745097] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Biomedical research is dominated by relatively few nonhuman animals to investigate healthy and disease conditions. Research has overrelied on these models due to their well-described genomes, the capability to control specific genes, and the high rate of reproduction. However, recent advances in large-scale molecular sequencing experiments have revealed, in some cases, the limited similarities in experimental outcomes observed in common rodents (i.e., mice) compared with humans. The value of more varied comparative animal models includes examples such as long-term body weight regulation in seasonally breeding hamsters as a means to help understand the obesity epidemic, vocal learning in songbirds to illuminate language acquisition and maintenance, and reproduction in cichlid fish to discover novel genes conserved in humans. Studying brain genes in prairie voles and cichlids advanced knowledge about social behavior. Taken together, experiments on diverse animal species highlight nontraditional systems for advancing our understanding of human health and well-being.
Collapse
|
29
|
Evaluation of the safety of conventional lighting replacement by artificial daylight. J Microsc Ultrastruct 2017; 5:206-215. [PMID: 30023256 PMCID: PMC6025781 DOI: 10.1016/j.jmau.2017.05.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 05/14/2017] [Indexed: 01/05/2023] Open
Abstract
Background Short morning exposure to high illuminance visible electromagnetic radiations termed as artificial daylight is beneficial for the mental health of people living in geographical areas with important seasonal changes in daylight illuminance. However, the commercial success of high illuminance light sources has raised the question of the safety of long hour exposure. Methods We have investigated the effect of the replacement of natural daylight by artificial daylight in Swiss mice raised under natural lighting conditions. Mice were monitored for neurotoxicity and general health changes. They were submitted to a battery of conventional tests for mood, motor and cognitive functions' assessment on exposure day (ED) 14 and ED20. Following sacrifice on ED21 due to marked signs of neurotoxicity, the expression of markers of inflammation and apoptosis was assessed in the entorhinal cortex and neurons were estimated in the hippocampal formation. Results Signs of severe cognitive and motor impairments, mood disorders, and hepatotoxicity were observed in animals exposed to artificial daylight on ED20, unlike on ED14 and unlike groups exposed to natural daylight or conventional lighting. Activated microglia and astrocytes were observed in the entorhinal cortex, as well as dead and dying neurons. Neuronal counts revealed massive neuronal loss in the hippocampal formation. Conclusions These results suggest that long hour exposure to high illuminance visible electromagnetic radiations induced severe alterations in brain function and general health in mice partly mediated by damages to the neocortex-entorhinal cortex-hippocampus axis. These findings raise caution over long hour use of high illuminance artificial light.
Collapse
|
30
|
Lewis JE, Ebling FJP. Tanycytes As Regulators of Seasonal Cycles in Neuroendocrine Function. Front Neurol 2017; 8:79. [PMID: 28344570 PMCID: PMC5344904 DOI: 10.3389/fneur.2017.00079] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 02/20/2017] [Indexed: 12/31/2022] Open
Abstract
Annual cycles of physiology and behavior are highly prevalent in organisms inhabiting temperate and polar regions. Examples in mammals include changes in appetite and body fat composition, hibernation and torpor, growth of antlers, pelage and horns, and seasonal reproduction. The timing of these seasonal cycles reflects an interaction of changing environmental signals, such as daylength, and intrinsic rhythmic processes: circannual clocks. As neuroendocrine signals underlie these rhythmic processes, the focus of most mechanistic studies has been on neuronal systems in the hypothalamus. Recent studies also implicate the pituitary stalk (pars tuberalis) and hypothalamic tanycytes as key pathways in seasonal timing. The pars tuberalis expresses a high density of melatonin receptors, so is highly responsive to changes in the nocturnal secretion of melatonin from the pineal gland as photoperiod changes across the year. The pars tuberalis in turn regulates tanycyte function in the adjacent hypothalamus via paracrine signals. Tanycytes are radial glial cells that persist into adulthood and function as a stem cell niche. Their cell soma are embedded in the ependymal lining of the third ventricle, and they also send elaborate projections through the arcuate nucleus, many of which terminate on capillaries in the median eminence. This anatomy underlies their function as sensors of nutrients in the circulation, and as regulators of transport of hormones and metabolites into the hypothalamus. In situ hybridization studies reveal robust seasonal changes in gene expression in tanycytes, for example, those controlling transport and metabolism of thyroid hormone and retinoic acid. These hormonal signals play a key role in the initial development of the brain, and experimental manipulation of thyroid hormone availability in the adult hypothalamus can accelerate or block seasonal cyclicity in sheep and Siberian hamsters. We hypothesize that seasonal rhythms depends upon reuse of developmental mechanisms in the adult hypothalamus and that tanycytes are key orchestrators of these processes.
Collapse
Affiliation(s)
- Jo E Lewis
- School of Life Sciences, University of Nottingham Medical School, Queen's Medical Centre , Nottingham , UK
| | - Francis J P Ebling
- School of Life Sciences, University of Nottingham Medical School, Queen's Medical Centre , Nottingham , UK
| |
Collapse
|
31
|
Stoney PN, Rodrigues D, Helfer G, Khatib T, Ashton A, Hay EA, Starr R, Kociszewska D, Morgan P, McCaffery P. A seasonal switch in histone deacetylase gene expression in the hypothalamus and their capacity to modulate nuclear signaling pathways. Brain Behav Immun 2017; 61:340-352. [PMID: 27993690 PMCID: PMC5325119 DOI: 10.1016/j.bbi.2016.12.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 12/01/2016] [Accepted: 12/13/2016] [Indexed: 12/28/2022] Open
Abstract
Seasonal animals undergo changes in physiology and behavior between summer and winter conditions. These changes are in part driven by a switch in a series of hypothalamic genes under transcriptional control by hormones and, of recent interest, inflammatory factors. Crucial to the control of transcription are histone deacetylases (HDACs), generally acting to repress transcription by local histone modification. Seasonal changes in hypothalamic HDAC transcripts were investigated in photoperiod-sensitive F344 rats by altering the day-length (photoperiod). HDAC4, 6 and 9 were found to change in expression. The potential influence of HDACs on two hypothalamic signaling pathways that regulate transcription, inflammatory and nuclear receptor signaling, was investigated. For inflammatory signaling the focus was on NF-κB because of the novel finding made that its expression is seasonally regulated in the rat hypothalamus. For nuclear receptor signaling it was discovered that expression of retinoic acid receptor beta was regulated seasonally. HDAC modulation of NF-κB-induced pathways was examined in a hypothalamic neuronal cell line and primary hypothalamic tanycytes. HDAC4/5/6 inhibition altered the control of gene expression (Fos, Prkca, Prkcd and Ptp1b) by inducers of NF-κB that activate inflammation. These inhibitors also modified the action of nuclear receptor ligands thyroid hormone and retinoic acid. Thus seasonal changes in HDAC4 and 6 have the potential to epigenetically modify multiple gene regulatory pathways in the hypothalamus that could act to limit inflammatory pathways in the hypothalamus during long-day summer-like conditions.
Collapse
Affiliation(s)
- Patrick N. Stoney
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK
| | - Diana Rodrigues
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK
| | - Gisela Helfer
- Rowett Institute of Nutrition and Health, University of Aberdeen, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, Scotland, UK,Faculty of Life Sciences, University of Bradford, Richmond Road, Bradford BD7 1DP, UK
| | - Thabat Khatib
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK
| | - Anna Ashton
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK
| | - Elizabeth A. Hay
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK
| | - Robert Starr
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK
| | - Dagmara Kociszewska
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK
| | - Peter Morgan
- Rowett Institute of Nutrition and Health, University of Aberdeen, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, Scotland, UK
| | - Peter McCaffery
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK.
| |
Collapse
|
32
|
Drew KL, Frare C, Rice SA. Neural Signaling Metabolites May Modulate Energy Use in Hibernation. Neurochem Res 2017; 42:141-150. [PMID: 27878659 PMCID: PMC5284051 DOI: 10.1007/s11064-016-2109-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 10/05/2016] [Accepted: 11/11/2016] [Indexed: 12/23/2022]
Abstract
Despite an epidemic in obesity and metabolic syndrome limited means exist to effect adiposity or metabolic rate other than life style changes. Here we review evidence that neural signaling metabolites may modulate thermoregulatory pathways and offer novel means to fine tune energy use. We extend prior reviews on mechanisms that regulate thermogenesis and energy use in hibernation by focusing primarily on the neural signaling metabolites adenosine, AMP and glutamate.
Collapse
Affiliation(s)
- Kelly L Drew
- Department of Chemistry and Biochemistry, Institute of Arctic Biology, University of Alaska Fairbanks, 902 N. Koyukuk Drive, Fairbanks, AK, 99775, USA.
| | - Carla Frare
- Department of Chemistry and Biochemistry, Institute of Arctic Biology, University of Alaska Fairbanks, 902 N. Koyukuk Drive, Fairbanks, AK, 99775, USA
| | - Sarah A Rice
- Department of Chemistry and Biochemistry, Institute of Arctic Biology, University of Alaska Fairbanks, 902 N. Koyukuk Drive, Fairbanks, AK, 99775, USA
| |
Collapse
|
33
|
Tarahovsky YS, Fadeeva IS, Komelina NP, Khrenov MO, Zakharova NM. Antipsychotic inductors of brain hypothermia and torpor-like states: perspectives of application. Psychopharmacology (Berl) 2017; 234:173-184. [PMID: 27933367 DOI: 10.1007/s00213-016-4496-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 11/26/2016] [Indexed: 12/12/2022]
Abstract
Hypothermia and hypometabolism (hypometabothermia) normally observed during natural hibernation and torpor, allow animals to protect their body and brain against the damaging effects of adverse environment. A similar state of hypothermia can be achieved under artificial conditions through physical cooling or pharmacological effects directed at suppression of metabolism and the processes of thermoregulation. In these conditions called torpor-like states, the mammalian ability to recover from stroke, heart attack, and traumatic injuries greatly increases. Therefore, the development of therapeutic methods for different pathologies is a matter of great concern. With the discovery of the antipsychotic drug chlorpromazine in the 1950s of the last century, the first attempts to create a pharmacologically induced state of hibernation for therapeutic purposes were made. That was the beginning of numerous studies in animals and the broad use of therapeutic hypothermia in medicine. Over the last years, many new agents have been discovered which were capable of lowering the body temperature and inhibiting the metabolism. The psychotropic agents occupy a significant place among them, which, in our opinion, is not sufficiently recognized in the contemporary literature. In this review, we summarized the latest achievements related to the ability of modern antipsychotics to target specific receptors in the brain, responsible for the initiation of hypometabothermia.
Collapse
Affiliation(s)
- Yury S Tarahovsky
- Institute of Cell Biophysics RAS, Pushchino, Moscow Region, Russian Federation, 142290. .,Institute of Theoretical and Experimental Biophysics RAS, Pushchino, Moscow Region, Russian Federation, 142290.
| | - Irina S Fadeeva
- Institute of Cell Biophysics RAS, Pushchino, Moscow Region, Russian Federation, 142290.,Institute of Theoretical and Experimental Biophysics RAS, Pushchino, Moscow Region, Russian Federation, 142290
| | - Natalia P Komelina
- Institute of Cell Biophysics RAS, Pushchino, Moscow Region, Russian Federation, 142290
| | - Maxim O Khrenov
- Institute of Cell Biophysics RAS, Pushchino, Moscow Region, Russian Federation, 142290
| | - Nadezhda M Zakharova
- Institute of Cell Biophysics RAS, Pushchino, Moscow Region, Russian Federation, 142290
| |
Collapse
|
34
|
Boswell T, Dunn IC. Regulation of Agouti-Related Protein and Pro-Opiomelanocortin Gene Expression in the Avian Arcuate Nucleus. Front Endocrinol (Lausanne) 2017; 8:75. [PMID: 28450851 PMCID: PMC5389969 DOI: 10.3389/fendo.2017.00075] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 03/27/2017] [Indexed: 12/25/2022] Open
Abstract
The arcuate nucleus is generally conserved across vertebrate taxa in its neuroanatomy and neuropeptide expression. Gene expression of agouti-related protein (AGRP), neuropeptide Y (NPY), pro-opiomelanocortin (POMC), and cocaine- and amphetamine-regulated transcript (CART) has been established in the arcuate nucleus of several bird species and co-localization demonstrated for AGRP and NPY. The proteins encoded by these genes exert comparable effects on food intake in birds after central administration to those seen in other vertebrates, with AGRP and NPY being orexigenic and CART and α-melanocyte-stimulating hormone anorexigenic. We have focused on the measurement of arcuate nucleus AGRP and POMC expression in several avian models in relation to the regulation of energy balance, incubation, stress, and growth. AGRP mRNA and POMC mRNA are, respectively, up- and downregulated after energy deprivation and restriction. This suggests that coordinated changes in the activity of AGRP and POMC neurons help to drive the homeostatic response to replace depleted energy stores in birds as in other vertebrates. While AGRP and POMC expression are generally positively and negatively correlated with food intake, respectively, we review here situations in some avian models in which AGRP gene expression is dissociated from the level of food intake and may have an influence on growth independent of changes in appetite. This suggests the possibility that the central melanocortin system exerts more pleiotropic functions in birds. While the neuroanatomical arrangement of AGRP and POMC neurons and the sensitivity of their activity to nutritional state appear generally conserved with other vertebrates, detailed knowledge is lacking of the key nutritional feedback signals acting on the avian arcuate nucleus and there appear to be significant differences between birds and mammals. In particular, recently identified avian leptin genes show differences between bird species in their tissue expression patterns and appear less closely linked in their expression to nutritional state. It is presently uncertain how the regulation of the central melanocortin system in birds is brought about in the situation of the apparently reduced importance of leptin and ghrelin compared to mammals.
Collapse
Affiliation(s)
- Timothy Boswell
- School of Biology, Newcastle University, Newcastle upon Tyne, UK
- *Correspondence: Timothy Boswell,
| | - Ian C. Dunn
- Royal (Dick) School of Veterinary Studies, Roslin Institute, University of Edinburgh, Easter Bush, UK
| |
Collapse
|
35
|
Chernysheva MP, Nozdrachev AD. Neuroendocrine hypothalamus as a homeostat of endogenous time. J EVOL BIOCHEM PHYS+ 2017. [DOI: 10.1134/s002209301701001x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
36
|
Kokolski M, Ebling FJ, Henstock JR, Anderson SI. Photoperiod-Induced Increases in Bone Mineral Apposition Rate in Siberian Hamsters and the Involvement of Seasonal Leptin Changes. Front Endocrinol (Lausanne) 2017; 8:357. [PMID: 29312147 PMCID: PMC5742149 DOI: 10.3389/fendo.2017.00357] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 12/07/2017] [Indexed: 11/13/2022] Open
Abstract
The adipokine leptin regulates energy balance, appetite, and reproductive maturation. Leptin also acts on bone growth and remodeling, but both osteogenic and anti-osteogenic effects have been reported depending on experimental conditions. Siberian hamsters (Phodopus sungorus) have natural variation in circulating leptin concentrations, where serum leptin is significantly decreased during the short day (SD)-induced winter state. In summer long day (LD) photoperiods, appetite and body adiposity increase with associated central leptin insensitivity. This natural change in leptin secretion was exploited to investigate leptin's effect on bone growth. Hamsters were injected with calcium-chelating fluorescent dyes to measure bone mineral apposition rate (MAR). Measurements were initially obtained from 5-week and 6-month-old animals maintained in low leptin (SD) or high leptin (LD) states. A further study investigated effects of chronic administration of recombinant mouse leptin to hamsters housed in SD and LD conditions; growth plate thickness and bone density were also assessed. As expected, a reduction in body mass was seen in hamsters exposed to SD, confirming the phenotype change in all studies. Serum leptin concentrations were significantly reduced in SD animals in all studies. MAR was reproducibly and significantly increased in the femurs of SD animals in all studies. Vitamin D and growth plate thickness were significantly increased in SD animals at 6 months. No effect on bone density was observed in any study. Taken together these data suggest that bone growth is associated with the low leptin, winter, lean state. In leptin-treated animals, there was a significant interaction effect of leptin and photoperiod. In comparison to their vehicle counterparts, SD animals had decreased and LD animals had increased MAR, which was not apparent prior to leptin administration. In conclusion, increased MAR was associated with low serum leptin levels in early life and sustained over 6 months, implying that leptin has a negative effect on bone growth in this model. The unexpected finding that MAR increased after peripheral leptin administration in LD suggests that leptin exerts different effects on bone growth dependent on initial leptin status. This adds further weight to the hypothesis that leptin-treated LD animals display central leptin resistance.
Collapse
Affiliation(s)
- Marie Kokolski
- Division of Medical Sciences and Graduate Entry Medicine, School of Medicine, University of Nottingham, Royal Derby Hospital, Derby, United Kingdom
- *Correspondence: Marie Kokolski,
| | - Francis J. Ebling
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - James R. Henstock
- Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Susan I. Anderson
- Division of Medical Sciences and Graduate Entry Medicine, School of Medicine, University of Nottingham, Royal Derby Hospital, Derby, United Kingdom
| |
Collapse
|
37
|
Verma R, Haldar C. Photoperiodic modulation of thyroid hormone receptor (TR-α), deiodinase-2 (Dio-2) and glucose transporters (GLUT 1 and GLUT 4) expression in testis of adult golden hamster, Mesocricetus auratus. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2016; 165:351-358. [DOI: 10.1016/j.jphotobiol.2016.10.036] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 10/29/2016] [Indexed: 10/20/2022]
|
38
|
Johnston RA, Paxton KL, Moore FR, Wayne RK, Smith TB. Seasonal gene expression in a migratory songbird. Mol Ecol 2016; 25:5680-5691. [DOI: 10.1111/mec.13879] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 09/17/2016] [Accepted: 09/21/2016] [Indexed: 12/23/2022]
Affiliation(s)
- Rachel A. Johnston
- Department of Ecology and Evolutionary Biology University of California, Los Angeles 610 Charles E Young Dr. South Rm. 4162 Los Angeles CA 90095 USA
| | - Kristina L. Paxton
- Department of Biological Sciences University of Southern Mississippi Hattiesburg MS 39406 USA
- Department of Biology University of Hawaii Hilo Hilo HI 96720 USA
| | - Frank R. Moore
- Department of Biological Sciences University of Southern Mississippi Hattiesburg MS 39406 USA
| | - Robert K. Wayne
- Department of Ecology and Evolutionary Biology University of California, Los Angeles 610 Charles E Young Dr. South Rm. 4162 Los Angeles CA 90095 USA
| | - Thomas B. Smith
- Department of Ecology and Evolutionary Biology University of California, Los Angeles 610 Charles E Young Dr. South Rm. 4162 Los Angeles CA 90095 USA
- Center for Tropical Research Institute of the Environment and Sustainability University of California, Los Angeles Los Angeles CA 90095 USA
| |
Collapse
|
39
|
Stevenson TJ, Visser ME, Arnold W, Barrett P, Biello S, Dawson A, Denlinger DL, Dominoni D, Ebling FJ, Elton S, Evans N, Ferguson HM, Foster RG, Hau M, Haydon DT, Hazlerigg DG, Heideman P, Hopcraft JGC, Jonsson NN, Kronfeld-Schor N, Kumar V, Lincoln GA, MacLeod R, Martin SAM, Martinez-Bakker M, Nelson RJ, Reed T, Robinson JE, Rock D, Schwartz WJ, Steffan-Dewenter I, Tauber E, Thackeray SJ, Umstatter C, Yoshimura T, Helm B. Disrupted seasonal biology impacts health, food security and ecosystems. Proc Biol Sci 2016; 282:20151453. [PMID: 26468242 PMCID: PMC4633868 DOI: 10.1098/rspb.2015.1453] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The rhythm of life on earth is shaped by seasonal changes in the environment. Plants and animals show profound annual cycles in physiology, health, morphology, behaviour and demography in response to environmental cues. Seasonal biology impacts ecosystems and agriculture, with consequences for humans and biodiversity. Human populations show robust annual rhythms in health and well-being, and the birth month can have lasting effects that persist throughout life. This review emphasizes the need for a better understanding of seasonal biology against the backdrop of its rapidly progressing disruption through climate change, human lifestyles and other anthropogenic impact. Climate change is modifying annual rhythms to which numerous organisms have adapted, with potential consequences for industries relating to health, ecosystems and food security. Disconcertingly, human lifestyles under artificial conditions of eternal summer provide the most extreme example for disconnect from natural seasons, making humans vulnerable to increased morbidity and mortality. In this review, we introduce scenarios of seasonal disruption, highlight key aspects of seasonal biology and summarize from biomedical, anthropological, veterinary, agricultural and environmental perspectives the recent evidence for seasonal desynchronization between environmental factors and internal rhythms. Because annual rhythms are pervasive across biological systems, they provide a common framework for trans-disciplinary research.
Collapse
Affiliation(s)
- T J Stevenson
- Institute for Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK
| | - M E Visser
- Department of Animal Ecology, Nederlands Instituut voor Ecologie, Wageningen, The Netherlands
| | - W Arnold
- Research Institute of Wildlife Ecology, University of Vienna, Vienna, Austria
| | - P Barrett
- Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, UK
| | - S Biello
- School of Psychology, University of Glasgow, Glasgow, UK
| | - A Dawson
- Centre for Ecology and Hydrology, Penicuik, Midlothian, UK
| | - D L Denlinger
- Department of Entomology, Ohio State University, Columbus, OH, USA
| | - D Dominoni
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - F J Ebling
- School of Life Sciences, University of Nottingham, Nottingham, UK
| | - S Elton
- Department of Anthropology, Durham University, Durham, UK
| | - N Evans
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - H M Ferguson
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - R G Foster
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - M Hau
- Max Planck Institute for Ornithology, Seewiesen, Germany
| | - D T Haydon
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - D G Hazlerigg
- Department of Arctic and Marine Biology, University of Tromso, Tromso, Norway
| | - P Heideman
- Department of Biology, The College of William and Mary, Williamsburg, VA, USA
| | - J G C Hopcraft
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - N N Jonsson
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | | | - V Kumar
- Department of Zoology, University of Delhi, Delhi, India
| | - G A Lincoln
- School of Biomedical Sciences, University of Edinburgh, Edinburgh, UK
| | - R MacLeod
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - S A M Martin
- Department of Animal Ecology, Nederlands Instituut voor Ecologie, Wageningen, The Netherlands
| | - M Martinez-Bakker
- Department of Ecology and Evolution, University of Michigan, Ann Arbor, MI, USA
| | - R J Nelson
- Department of Psychology, Ohio State University, Columbus, OH, USA
| | - T Reed
- Aquaculture and Fisheries Development Centre, University of College Cork, Cork, Ireland
| | - J E Robinson
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - D Rock
- School of Psychiatry and Clinical Neurosciences, University of Western Australia, Perth, Australia
| | - W J Schwartz
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA, USA
| | - I Steffan-Dewenter
- Department of Animal Ecology and Tropical Biology, University of Wuerzburg, Wuerzburg, Germany
| | - E Tauber
- Department of Genetics, University of Leicester, Leicester, UK
| | - S J Thackeray
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - C Umstatter
- Agroscope, Tanikon, CH-8356 Ettenhausen, Switzerland
| | - T Yoshimura
- Department of Applied Molecular Biosciences, University of Nagoya, Nagoya, Japan
| | - B Helm
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| |
Collapse
|
40
|
Little AG. A review of the peripheral levels of regulation by thyroid hormone. J Comp Physiol B 2016; 186:677-88. [DOI: 10.1007/s00360-016-0984-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 03/23/2016] [Accepted: 03/29/2016] [Indexed: 12/12/2022]
|
41
|
Chayama Y, Ando L, Tamura Y, Miura M, Yamaguchi Y. Decreases in body temperature and body mass constitute pre-hibernation remodelling in the Syrian golden hamster, a facultative mammalian hibernator. ROYAL SOCIETY OPEN SCIENCE 2016; 3:160002. [PMID: 27152216 PMCID: PMC4852639 DOI: 10.1098/rsos.160002] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Accepted: 03/08/2016] [Indexed: 06/02/2023]
Abstract
Hibernation is an adaptive strategy for surviving during periods with little or no food availability, by profoundly reducing the metabolic rate and the core body temperature (T b). Obligate hibernators (e.g. bears, ground squirrels, etc.) hibernate every winter under the strict regulation of endogenous circannual rhythms, and they are assumed to undergo adaptive remodelling in autumn, the pre-hibernation period, prior to hibernation. However, little is known about the nature of pre-hibernation remodelling. Syrian hamsters (Mesocricetus auratus) are facultative hibernators that can hibernate irrespective of seasons when exposed to prolonged short photoperiod and cold ambient temperature (SD-Cold) conditions. Their T b set point reduced by the first deep torpor (DT) and then increased gradually after repeated cycles of DT and periodic arousal (PA), and finally recovered to the level observed before the prolonged SD-Cold in the post-hibernation period. We also found that, before the initiation of hibernation, the body mass of animals decreased below a threshold, indicating that hibernation in this species depends on body condition. These observations suggest that Syrian hamsters undergo pre-hibernation remodelling and that T b and body mass can be useful physiological markers to monitor the remodelling process during the pre-hibernation period.
Collapse
Affiliation(s)
- Yuichi Chayama
- Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Lisa Ando
- Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yutaka Tamura
- Department of Pharmacology, Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, Fukuyama 729-0292, Japan
| | - Masayuki Miura
- Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
- AMED-CREST, Japan Agency for Medical Research and Development, Chiyoda-ku, Tokyo 100-0004, Japan
| | - Yoshifumi Yamaguchi
- Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
- Precursory Research for Embryonic Science and Technology, Japan Science and Technology Agency, Chiyoda-ku, Tokyo 102-0076, Japan
| |
Collapse
|
42
|
Banks R, Delibegovic M, Stevenson TJ. Photoperiod- and Triiodothyronine-dependent Regulation of Reproductive Neuropeptides, Proinflammatory Cytokines, and Peripheral Physiology in Siberian Hamsters (Phodopus sungorus). J Biol Rhythms 2016; 31:299-307. [DOI: 10.1177/0748730416637707] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Seasonal trade-offs in reproduction and immunity are ubiquitous in nature. The mechanisms that govern transitions across seasonal physiological states appear to involve reciprocal switches in the local synthesis of thyroid hormone. In long-day (LD) summer-like conditions, increased hypothalamic triiodothyronine (T3) stimulates gonadal development. Alternatively, short-day (SD) winter-like conditions increase peripheral leukocytes and enhance multiple aspects of immune function. These data indicate that the localized effects of T3 in the hypothalamus and leukocytes are photoperiod dependent. We tested the hypothesis that increased peripheral T3 in SD conditions would increase aspects of reproductive physiology and inhibit immune function, whereas T3 injections in LD conditions would facilitate aspects of immune function (i.e., leukocytes). In addition, we also examined whether T3 regulates hypothalamic neuropeptide expression as well as hypothalamic and splenic proinflammatory cytokine expression. Adult male Siberian hamsters were maintained in LD (15L:9D) or transferred to SD (9L:15D) for 8 weeks. A subset of LD and SD hamsters was treated daily with 5 µg T3 for 2 weeks. LD and SD controls were injected with saline. Daily T3 administration in SD hamsters (SD+T3) resulted in a rapid and substantial decrease in peripheral leukocyte concentrations and stimulated gonadal development. T3 treatment in LD (LD+T3) had no effect on testicular volumes but significantly increased leukocyte concentrations. Molecular analyses revealed that T3 stimulated interleukin 1β messenger RNA (mRNA) expression in the spleen and inhibited RFamide Related Peptide-3 mRNA expression in the hypothalamus. Moreover, there was a photoperiod-dependent decrease in splenic tumor necrosis factor–α mRNA expression. These findings reveal that T3 has tissue-specific and photoperiod-dependent regulation of seasonal rhythms in reproduction and immune function.
Collapse
Affiliation(s)
- Ruth Banks
- Institute for Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | | | - Tyler J. Stevenson
- Institute for Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK
| |
Collapse
|
43
|
Lewis JE, Brameld JM, Hill P, Wilson D, Barrett P, Ebling FJP, Jethwa PH. Thyroid hormone and vitamin D regulate VGF expression and promoter activity. J Mol Endocrinol 2016; 56:123-34. [PMID: 26643910 PMCID: PMC4705542 DOI: 10.1530/jme-15-0224] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/03/2015] [Indexed: 01/20/2023]
Abstract
The Siberian hamster (Phodopus sungorus) survives winter by decreasing food intake and catabolizing abdominal fat reserves, resulting in a sustained, profound loss of body weight. Hypothalamic tanycytes are pivotal for this process. In these cells, short-winter photoperiods upregulate deiodinase 3, an enzyme that regulates thyroid hormone availability, and downregulate genes encoding components of retinoic acid (RA) uptake and signaling. The aim of the current studies was to identify mechanisms by which seasonal changes in thyroid hormone and RA signaling from tanycytes might ultimately regulate appetite and energy expenditure. proVGF is one of the most abundant peptides in the mammalian brain, and studies have suggested a role for VGF-derived peptides in the photoperiodic regulation of body weight in the Siberian hamster. In silico studies identified possible thyroid and vitamin D response elements in the VGF promoter. Using the human neuroblastoma SH-SY5Y cell line, we demonstrate that RA increases endogenous VGF expression (P<0.05) and VGF promoter activity (P<0.0001). Similarly, treatment with 1,25-dihydroxyvitamin D3 increased endogenous VGF mRNA expression (P<0.05) and VGF promoter activity (P<0.0001), whereas triiodothyronine (T3) decreased both (P<0.01 and P<0.0001). Finally, intra-hypothalamic administration of T3 blocked the short day-induced increase in VGF expression in the dorsomedial posterior arcuate nucleus of Siberian hamsters. Thus, we conclude that VGF expression is a likely target of photoperiod-induced changes in tanycyte-derived signals and is potentially a regulator of seasonal changes in appetite and energy expenditure.
Collapse
Affiliation(s)
- Jo E Lewis
- Division of Nutritional SciencesSchool of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UKSchool of Life SciencesUniversity of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UKThe Rowett Institute of Nutrition and HealthUniversity of Aberdeen, Bucksburn, Aberdeen AB21 9SB, UK Division of Nutritional SciencesSchool of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UKSchool of Life SciencesUniversity of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UKThe Rowett Institute of Nutrition and HealthUniversity of Aberdeen, Bucksburn, Aberdeen AB21 9SB, UK
| | - John M Brameld
- Division of Nutritional SciencesSchool of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UKSchool of Life SciencesUniversity of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UKThe Rowett Institute of Nutrition and HealthUniversity of Aberdeen, Bucksburn, Aberdeen AB21 9SB, UK
| | - Phil Hill
- Division of Nutritional SciencesSchool of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UKSchool of Life SciencesUniversity of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UKThe Rowett Institute of Nutrition and HealthUniversity of Aberdeen, Bucksburn, Aberdeen AB21 9SB, UK
| | - Dana Wilson
- Division of Nutritional SciencesSchool of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UKSchool of Life SciencesUniversity of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UKThe Rowett Institute of Nutrition and HealthUniversity of Aberdeen, Bucksburn, Aberdeen AB21 9SB, UK
| | - Perry Barrett
- Division of Nutritional SciencesSchool of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UKSchool of Life SciencesUniversity of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UKThe Rowett Institute of Nutrition and HealthUniversity of Aberdeen, Bucksburn, Aberdeen AB21 9SB, UK
| | - Francis J P Ebling
- Division of Nutritional SciencesSchool of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UKSchool of Life SciencesUniversity of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UKThe Rowett Institute of Nutrition and HealthUniversity of Aberdeen, Bucksburn, Aberdeen AB21 9SB, UK
| | - Preeti H Jethwa
- Division of Nutritional SciencesSchool of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UKSchool of Life SciencesUniversity of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UKThe Rowett Institute of Nutrition and HealthUniversity of Aberdeen, Bucksburn, Aberdeen AB21 9SB, UK
| |
Collapse
|
44
|
Pattinson CL, Allan AC, Staton SL, Thorpe KJ, Smith SS. Environmental Light Exposure Is Associated with Increased Body Mass in Children. PLoS One 2016; 11:e0143578. [PMID: 26735299 PMCID: PMC4711797 DOI: 10.1371/journal.pone.0143578] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 11/07/2015] [Indexed: 12/21/2022] Open
Abstract
The timing, intensity, and duration of exposure to both artificial and natural light have acute metabolic and physiological effects in mammals. Recent research in human adults suggests exposure to moderate intensity light later in the day is concurrently associated with increased body mass; however, no studies have investigated the effect of light exposure on body mass in young children. We examined objectively measured light exposure and body mass of 48 preschool-aged children at baseline, and measured their body mass again 12 months later. At baseline, moderate intensity light exposure earlier in the day was associated with increased body mass index (BMI). Increased duration of light exposure at baseline predicted increased BMI 12-months later, even after controlling for baseline sleep duration, sleep timing, BMI, and activity. The findings identify that light exposure may be a contributor to the obesogenic environment during early childhood.
Collapse
Affiliation(s)
- Cassandra L. Pattinson
- Centre for Children’s Health Research, Institute for Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Queensland, Australia
| | - Alicia C. Allan
- Centre for Accident Research and Road Safety – Queensland (CARRS-Q), Queensland University of Technology, Kelvin Grove, Queensland, Australia
| | - Sally L. Staton
- Centre for Children’s Health Research, Institute for Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Queensland, Australia
| | - Karen J. Thorpe
- Centre for Children’s Health Research, Institute for Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Queensland, Australia
| | - Simon S. Smith
- Centre for Children’s Health Research, Institute for Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Queensland, Australia
- Centre for Accident Research and Road Safety – Queensland (CARRS-Q), Queensland University of Technology, Kelvin Grove, Queensland, Australia
| |
Collapse
|
45
|
Kuba J, Błaszczyk B, Stankiewicz T, Skuratko A, Udała J. Analysis of Annual Changes in the Concentrations of Selected Macro- and Microelements, Thyroxine, and Testosterone in the Serum of Red Deer (Cervus elaphus) Stags. Biol Trace Elem Res 2015; 168:356-61. [PMID: 25998797 DOI: 10.1007/s12011-015-0368-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 05/12/2015] [Indexed: 10/23/2022]
Abstract
The aim of the study was to analyze seasonal changes in the concentrations of calcium, phosphorus, magnesium, and selenium as well as thyroxine and testosterone in adult red deer stags. The highest testosterone concentrations (mean 6.29±4.36 ng/ml) were observed from the end of August to November, confirming an increase in testicular secretory activity during the mating season. The changes in thyroxine concentration show circannual rhythms, most likely related to changes in the air temperature. The highest mean level of thyroxine was observed in spring (55.69±10.99 ng/ml). The concentration of selenium also reached the highest level during this season (0.107±0.027 μg/ml). In the case of the studied macroelements, the concentrations were stable from spring to summer but then decreased to the lowest mean values in autumn in both years of the experiment (Ca, 61.17±10.60; P, 47.08±9.59; Mg, 15.96±2.39 μg/ml). The dynamics of thyroxine secretion does not seem to affect directly the metabolism of calcium, phosphorus, and magnesium. In turn, sexual activity, manifested in the increase in secretion of testosterone, may affect changes in the concentration of calcium. Additionally, we cannot exclude a connection between changes in the concentrations of testosterone and selenium.
Collapse
Affiliation(s)
- J Kuba
- Department of Animal Reproduction Biotechnology and Environmental Hygiene, West Pomeranian University of Technology in Szczecin, Dr. Judyma 6, 71-466, Szczecin, Poland.
| | - B Błaszczyk
- Department of Animal Reproduction Biotechnology and Environmental Hygiene, West Pomeranian University of Technology in Szczecin, Dr. Judyma 6, 71-466, Szczecin, Poland
| | - T Stankiewicz
- Department of Animal Reproduction Biotechnology and Environmental Hygiene, West Pomeranian University of Technology in Szczecin, Dr. Judyma 6, 71-466, Szczecin, Poland
| | - A Skuratko
- Department of Animal Reproduction Biotechnology and Environmental Hygiene, West Pomeranian University of Technology in Szczecin, Dr. Judyma 6, 71-466, Szczecin, Poland
| | - J Udała
- Department of Animal Reproduction Biotechnology and Environmental Hygiene, West Pomeranian University of Technology in Szczecin, Dr. Judyma 6, 71-466, Szczecin, Poland
| |
Collapse
|
46
|
Photoperiod Regulates vgf-Derived Peptide Processing in Siberian Hamsters. PLoS One 2015; 10:e0141193. [PMID: 26555143 PMCID: PMC4640585 DOI: 10.1371/journal.pone.0141193] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 10/05/2015] [Indexed: 12/26/2022] Open
Abstract
VGF mRNA is induced in specific hypothalamic areas of the Siberian hamster upon exposure to short photoperiods, which is associated with a seasonal decrease in appetite and weight loss. Processing of VGF generates multiple bioactive peptides, so the objective of this study was to determine the profile of the VGF-derived peptides in the brain, pituitary and plasma from Siberian hamsters, and to establish whether differential processing might occur in the short day lean state versus long day fat. Antisera against short sequences at the C- or N- termini of proVGF, as well as against NERP-1, TPGH and TLQP peptides, were used for analyses of tissues, and both immunohistochemistry and enzyme linked immunosorbent assay (ELISA) coupled with high-performance liquid (HPLC) or gel chromatography were carried out. VGF peptide immunoreactivity was found within cortex cholinergic perikarya, in multiple hypothalamic nuclei, including those containing vasopressin, and in pituitary gonadotrophs. ELISA revealed that exposure to short day photoperiod led to a down-regulation of VGF immunoreactivity in the cortex, and a less pronounced decrease in the hypothalamus and pituitary, while the plasma VGF levels were not affected by the photoperiod. HPLC and gel chromatography both confirmed the presence of multiple VGF-derived peptides in these tissues, while gel chromatography showed the presence of the VGF precursor in all tissues tested except for the cortex. These observations are consistent with the view that VGF-derived peptides have pleiotropic actions related to changing photoperiod, possibly by regulating cholinergic systems in the cortex, vasopressin hypothalamic pathways, and the reproductive axis.
Collapse
|
47
|
Antibody-Mediated Inhibition of the FGFR1c Isoform Induces a Catabolic Lean State in Siberian Hamsters. Curr Biol 2015; 25:2997-3003. [PMID: 26549257 DOI: 10.1016/j.cub.2015.10.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 09/01/2015] [Accepted: 10/05/2015] [Indexed: 11/24/2022]
Abstract
Hypothalamic tanycytes are considered to function as sensors of peripheral metabolism. To facilitate this role, they express a wide range of receptors, including fibroblast growth factor receptor 1 (FGFR1). Using a monoclonal antibody (IMC-H7) that selectively antagonizes the FGFR1c isoform, we investigated possible actions of FGFR1c in a natural animal model of adiposity, the Siberian hamster. Infusion of IMC-H7 into the third ventricle suppressed appetite and increased energy expenditure. Likewise, peripheral treatment with IMC-H7 decreased appetite and body weight and increased energy expenditure and fat oxidation. A greater reduction in body weight and caloric intake was observed in response to IMC-H7 during the long-day fat state as compared to the short-day lean state. This enhanced response to IMC-H7 was also observed in calorically restricted hamsters maintained in long days, suggesting that it is the central photoperiodic state rather than the peripheral adiposity that determines the response to FGFR1c antagonism. Hypothalamic thyroid hormone availability is controlled by deiodinase enzymes (DIO2 and DIO3) expressed in tanycytes and is the key regulator of seasonal cycles of energy balance. Therefore, we determined the effect of IMC-H7 on hypothalamic expression of these deiodinase enzymes. The reductions in food intake and body weight were always associated with decreased expression of DIO2 in the hypothalamic ependymal cell layer containing tanycytes. These data provide further support for the notion the tanycytes are an important component of the mechanism by which the hypothalamus integrates central and peripheral signals to regulate energy intake and expenditure.
Collapse
|
48
|
Samms RJ, Murphy M, Fowler MJ, Cooper S, Emmerson P, Coskun T, Adams AC, Kharitonenkov A, Ebling FJP, Tsintzas K. Dual effects of fibroblast growth factor 21 on hepatic energy metabolism. J Endocrinol 2015; 227:37-47. [PMID: 26294388 DOI: 10.1530/joe-15-0334] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/18/2015] [Indexed: 12/13/2022]
Abstract
The aim of this study was to investigate the mechanisms by which fibroblast growth factor 21 (FGF21) affects hepatic integration of carbohydrate and fat metabolism in Siberian hamsters, a natural model of adiposity. Twelve aged matched adult male Siberian hamsters maintained in their long-day fat state since birth were randomly assigned to one of two treatment groups and were continuously infused with either vehicle (saline; n=6) or recombinant human FGF21 protein (1 mg/kg per day; n=6) for 14 days. FGF21 administration caused a 40% suppression (P<0.05) of hepatic pyruvate dehydrogenase complex (PDC), the rate-limiting step in glucose oxidation, a 34% decrease (P<0.05) in hepatic acetylcarnitine accumulation, an index of reduced PDC flux, a 35% increase (P<0.05) in long-chain acylcarnitine content (an index of flux through β-oxidation) and a 47% reduction (P<0.05) in hepatic lipid content. These effects were underpinned by increased protein abundance of PD kinase-4 (PDK4, a negative regulator of PDC), the phosphorylated (inhibited) form of acetyl-CoA carboxylase (ACC, a negative regulator of delivery of fatty acids into the mitochondria) and the transcriptional co-regulators of energy metabolism peroxisome proliferator activated receptor gamma co-activator alpha (PGC1α) and sirtuin-1. These findings provide novel mechanistic basis to support the notion that FGF21 exerts profound metabolic benefits in the liver by modulating nutrient flux through both carbohydrate (mediated by a PDK4-mediated suppression of PDC activity) and fat (mediated by deactivation of ACC) metabolism, and therefore may be an attractive target for protection from increased hepatic lipid content and insulin resistance that frequently accompany obesity and diabetes.
Collapse
Affiliation(s)
- Ricardo J Samms
- School of Life SciencesQueen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UKLilly Research LaboratoriesIndianapolis, IN, USAChemistry DepartmentCollege of Arts and Sciences, Indiana University Bloomington, 800 East Kirkwood Avenue, Bloomington, IN 47405-7102, USA
| | - Michelle Murphy
- School of Life SciencesQueen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UKLilly Research LaboratoriesIndianapolis, IN, USAChemistry DepartmentCollege of Arts and Sciences, Indiana University Bloomington, 800 East Kirkwood Avenue, Bloomington, IN 47405-7102, USA
| | - Maxine J Fowler
- School of Life SciencesQueen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UKLilly Research LaboratoriesIndianapolis, IN, USAChemistry DepartmentCollege of Arts and Sciences, Indiana University Bloomington, 800 East Kirkwood Avenue, Bloomington, IN 47405-7102, USA
| | - Scott Cooper
- School of Life SciencesQueen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UKLilly Research LaboratoriesIndianapolis, IN, USAChemistry DepartmentCollege of Arts and Sciences, Indiana University Bloomington, 800 East Kirkwood Avenue, Bloomington, IN 47405-7102, USA
| | - Paul Emmerson
- School of Life SciencesQueen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UKLilly Research LaboratoriesIndianapolis, IN, USAChemistry DepartmentCollege of Arts and Sciences, Indiana University Bloomington, 800 East Kirkwood Avenue, Bloomington, IN 47405-7102, USA
| | - Tamer Coskun
- School of Life SciencesQueen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UKLilly Research LaboratoriesIndianapolis, IN, USAChemistry DepartmentCollege of Arts and Sciences, Indiana University Bloomington, 800 East Kirkwood Avenue, Bloomington, IN 47405-7102, USA
| | - Andrew C Adams
- School of Life SciencesQueen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UKLilly Research LaboratoriesIndianapolis, IN, USAChemistry DepartmentCollege of Arts and Sciences, Indiana University Bloomington, 800 East Kirkwood Avenue, Bloomington, IN 47405-7102, USA
| | - Alexei Kharitonenkov
- School of Life SciencesQueen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UKLilly Research LaboratoriesIndianapolis, IN, USAChemistry DepartmentCollege of Arts and Sciences, Indiana University Bloomington, 800 East Kirkwood Avenue, Bloomington, IN 47405-7102, USA
| | - Francis J P Ebling
- School of Life SciencesQueen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UKLilly Research LaboratoriesIndianapolis, IN, USAChemistry DepartmentCollege of Arts and Sciences, Indiana University Bloomington, 800 East Kirkwood Avenue, Bloomington, IN 47405-7102, USA
| | - Kostas Tsintzas
- School of Life SciencesQueen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UKLilly Research LaboratoriesIndianapolis, IN, USAChemistry DepartmentCollege of Arts and Sciences, Indiana University Bloomington, 800 East Kirkwood Avenue, Bloomington, IN 47405-7102, USA
| |
Collapse
|
49
|
McMillan AC, White MD. Induction of thermogenesis in brown and beige adipose tissues: molecular markers, mild cold exposure and novel therapies. Curr Opin Endocrinol Diabetes Obes 2015; 22:347-52. [PMID: 26313896 DOI: 10.1097/med.0000000000000191] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
PURPOSE OF REVIEW The purpose of this short review paper is to summarize recent developments in the understanding of the activation, growth and function of brown adipose tissue (BAT). RECENT FINDINGS Transcriptional markers for increased BAT activity and differentiation of white adipocytes to 'beige' or 'brite' adipocytes include amongst others peroxisome proliferator-activated receptor γ, cytosine-enhancer-binding protein, positive regulatory domain 16 and bone morphogenetic proteins. These markers induce uncoupling protein 1 expression in brown and 'beige' or 'brite' adipocytes which allows energy from macronutrients to be expended as heat. Acute and repeated mild cold exposures of 17-19 °C in adult humans increase BAT volume and activity and this is a novel method for increasing their energy expenditure. Emerging evidence suggests that irisin and melatonin hormones may be involved in BAT activation. Additionally, brown adipocyte stem cell therapy transplantation is a means to stimulate this increased thermogenesis from brown and 'beige' or 'brite' adipocytes. SUMMARY Markers for increased BAT activation and for white adipocyte differentiation into beige/brite adipocytes have been identified, and these lead to an uncoupling protein 1-mediated increase in metabolic rate. Mild cold exposure and brown adipocyte stem cell transplantation are two potential strategies for inducing activation and growth of BAT for the treatment of human obesity.
Collapse
Affiliation(s)
- Andrew C McMillan
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, British Columbia, Canada
| | | |
Collapse
|
50
|
Boswell T, Dunn IC. Regulation of the avian central melanocortin system and the role of leptin. Gen Comp Endocrinol 2015; 221:278-83. [PMID: 25583584 DOI: 10.1016/j.ygcen.2014.12.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 12/19/2014] [Indexed: 01/10/2023]
Abstract
The avian central melanocortin system is well conserved between birds and mammals in terms of the component genes, the localisation of their expression in the hypothalamic arcuate nucleus, the effects on feeding behaviour of their encoded peptides and the sensitivity of agouti-related protein (AGRP) and pro-opiomelanocortin (POMC) gene expression to changes in energy status. Our recent research has demonstrated that AGRP gene expression precisely differentiates between broiler breeder hens with different histories of chronic food restriction and refeeding. We have also shown that the sensitivity of AGRP gene expression to loss of energy stores is maintained even when food intake has been voluntarily reduced in chickens during incubation and in response to a stressor. However, the similarity between birds and mammals does not appear to extend to the way AGRP and POMC gene expression are regulated. In particular, the preliminary evidence from the discovery of the first avian leptin (LEP) genes suggests that LEP is more pleiotropic in birds and may not even be involved in regulating energy balance. Similarly, ghrelin exerts inhibitory, rather than stimulatory, effects on food intake. The fact that the importance of these prominent long-term regulators of AGRP and POMC expression in mammals appears diminished in birds suggests that the balance of regulatory inputs in birds may have shifted to more short-term influences such as the tone of cholecystokinin (CCK) signalling. This is likely to be related to the different metabolic fuelling required to support flight.
Collapse
Affiliation(s)
- Timothy Boswell
- School of Biology, Institute of Neuroscience, Centre for Behaviour and Evolution, Newcastle University, England, United Kingdom.
| | - Ian C Dunn
- Royal (Dick) School of Veterinary Studies, Roslin Institute, University of Edinburgh, Easter Bush, Scotland, United Kingdom
| |
Collapse
|