Endocrine and molecular regulation of seasonal avian immune function

Philosophical Transactions of the Royal Society B Biological Sciences, Journal Year: 2025, Volume and Issue: 380(1918)

Published: Jan. 23, 2025

Birds have evolved seasonal adaptations in multiple aspects of the innate and adaptive immune systems. Seasonal immunological are crucial for survival harsh environmental conditions response to increased prevalence acute chronic diseases. Similar other vertebrates, birds exhibit remarkable plasticity cytokine production, chemotaxis, phagocytosis inflammation across year. In this review, we provide a comparative perspective on rhythms bird function. We describe advances our understanding annual changes cells responses challenges. Then, role glucocorticoids, sex steroids, thyroid hormones (THs) melatonin act as immunomodulators is described. then discuss impact major emerging disease, high pathogenicity avian influenza, one most critical diseases with significant implications poultry wild populations. The review identifies need enhance knowledge tissues birds, at molecular, cellular hormonal levels Moreover, there absence information sex-specific variation Understanding system dynamics will aid addressing negative impacts pathogenic diseases, minimize global economic losses conservation efforts.This article part Theo Murphy meeting issue 'Circadian infection immunity'.

Language: Английский

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Functional inhibition of deep brain non-visual opsins facilitates acute long day induction of reproductive recrudescence in male Japanese quail

Hormones and Behavior, Journal Year: 2023, Volume and Issue: 148, P. 105298 - 105298

Published: Jan. 6, 2023

Language: Английский

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Photoperiodic regulation of avian physiology: From external coincidence to seasonal reproduction

Journal of Experimental Zoology Part A Ecological and Integrative Physiology, Journal Year: 2022, Volume and Issue: 337(9-10), P. 890 - 901

Published: May 10, 2022

Abstract Seasonal cycles of environmental cues generate variation in the timing life‐history transition events across taxa. It is through entrainment internal, endogenous rhythms organisms to these external, exogenous environment, such as cycling temperature and daylight, by which can regulate time life history transitions. Here, we review current understanding how photoperiod both stimulates terminates seasonal reproduction birds. The describes role external coincidence timing, process proposed stimulate reproductive development. Then, molecular basis light detection photoperiodic regulation neuroendocrine birds presented. Current data indicates that vertebrate ancient opsin predominant photoreceptor for hypothalamus, compared neuropsin rhodopsin. then connects well‐characterized hypothalamic pituitary gland molecules involved reproduction. In birds, Gonadotropin‐releasing hormone synthesis release are controlled via thyrotropin‐stimulating hormone‐β (TSHβ) independent dependent pathways, respectively. highlights D‐box E‐box binding motifs promoter regions genes, particular Eyes‐absent 3, key link between circadian clock function measurement. Based on available evidence, proposes at least two programs form birds: responsiveness TSHβ pathways internal gonadotropin synthesis.

Language: Английский

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Photoperiod-driven testicular DNA methylation in gonadotropin and sex steroid receptor promoters in Siberian hamsters

Journal of Comparative Physiology A, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 15, 2025

Seasonal cycles in breeding, often orchestrated by annual changes photoperiod, are common nature. Here, we studied how change photoperiod affects DNA methylation the testes of a highly seasonal breeder: Siberian hamster (Phodopus sungorus). We hypothesized that promoter regions associated with key reproductive genes such as follicle-stimulating hormone receptor is linked to breeding and non-breeding states. Using Oxford Nanopore sequencing, identified more than 10 million (10,151,742) differentially methylated cytosine-guanine (CpG) sites genome between long short conditions. ShinyGo enrichment analyses biological pathways consisting system, hormone-mediated signalling gonad development. found induced for androgen (Ar), estrogen receptors (Esr1, Esr2), kisspeptin1 (kiss1r) (Fshr). Long photoperiods were observed have higher promoters basic helix-loop-helix ARNT-like 1 (Bmal1), progesterone (Pgr) thyroid-stimulating (Tshr). Our findings provide insights into epigenetic mechanisms underlying adaptations timing reproduction hamsters could be informative understanding male fertility disorders mammals.

Language: Английский

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Mechanisms matching timing to resources: comparisons of closely related seasonally sympatric, migratory and non‐migratory populations

Journal of Avian Biology, Journal Year: 2025, Volume and Issue: 2025(2)

Published: March 1, 2025

As day length increases in spring, birds prepare to migrate and breed, relying on timing mechanisms shaped by selection match their behavior physiology ecological conditions suitable for reproduction. the climate changes these will determine how successful be keeping up. In this contribution, we review studies comparing photoperiodic thresholds, endocrine profiles of testosterone corticosterone, gene expression during pre‐breeding seasonally sympatric migratory resident populations a songbird, dark‐eyed junco Junco hyemalis . Elevation response GnRH served as proxy gonadal development, visible fat state, stable isotopes feathers claws breeding non‐breeding latitudes. Living same environment, migrants prepared fattening delaying while residents initiated development not fattening. Within migrants, estimated latitude origin co‐varied positively with negatively development. Together likely serve migration reproduction future appearance favorable environments where occur. Differences observed wild persisted common suggesting genetic divergence local adaptation, though possibility early developmental effects remain. warms resources support appear earlier, locally adapted dispersing immigrants from lower latitudes may bring along earlier thus providing or rescue. Future research responsible variation among allow better predictions adaptation change unfold. Keywords: garden, junco, gonad, hormone, migration, phenology, threshold, isotope

Language: Английский

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Timing mismatches, carryover effects, and the role of neuroendocrine mechanisms in determining birds' responses to environmental change

Journal of Neuroendocrinology, Journal Year: 2025, Volume and Issue: unknown

Published: April 23, 2025

Abstract The neuroendocrine system plays a critical role in the synchronization of life cycle stages with variation environment, and coordination one another. When humans modify environments, these mechanisms may impact how different individuals, populations, species, even communities are affected. Here we conceptualize endocrine influence likelihood of: (1) timing mismatches between environmental conditions, (2) carryover effects within annual cycles. Timing can occur when an individual fails to synchronize particular stage appropriate conditions. Carryover activities (including its timing) affect performance or more subsequent stages. We suggest that there is trade‐off adjustments across such reduce temporally changing environments (e.g., strong responsiveness short‐term cues, resultant increased temporal flexibility fine‐tune current local conditions) inherently increase through delay transition stages), vice versa. use two examples—flexibility onset photorefractoriness mediated by sensitivity molt sex steroids—to illustrate ideas, future work should investigate impacts potentially other seasonal on effects. conceptual framework presented here suggests be no single best set tactics for coping climate change; species facilitating avoid some but themselves up deleterious as they make conditions modified change.

Language: Английский

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Seasonality of prolactin in birds and mammals

Journal of Experimental Zoology Part A Ecological and Integrative Physiology, Journal Year: 2022, Volume and Issue: 337(9-10), P. 919 - 938

Published: June 10, 2022

Abstract In most animals, annual rhythms in environmental cues and internal programs regulate seasonal physiology behavior. Prolactin, an evolutionarily ancient hormone, serves as a molecular correlate of timing species. Prolactin is highly pleiotropic with wide variety well‐documented physiological effects; context prolactin known to changes pelage molt. While short‐term homeostatic variation secretion under the control hypothalamus, long‐term are programmed by endogenous timers that reside pituitary gland. The basis these generally understood be melatonin dependent mammals. rhythmicity persists for several years many species, absence hypothalamic signaling. Such evidence mammals has supported hypothesis derive from timer within gland entrained external photoperiod. this review, we describe conserved nature signaling birds highlight its role regulating multiple diverse systems. review will cover current understanding seasonality propose mechanism which may generated amniotes.

Language: Английский

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Sex and seasonal differences in neural steroid sensitivity predict territorial aggression in Siberian hamsters

Hormones and Behavior, Journal Year: 2023, Volume and Issue: 154, P. 105390 - 105390

Published: June 22, 2023

Language: Английский

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Mechanisms matching timing to resources: comparisons of closely related, seasonally sympatric, migratory and non-migratory populations

Authorea (Authorea), Journal Year: 2024, Volume and Issue: unknown

Published: Aug. 27, 2024

As day length increases in spring, birds prepare to migrate and breed, relying on timing mechanisms shaped by selection match ecological conditions suitable for reproduction. the climate changes these will determine how successful be keeping up. In this contribution, we review studies comparing free-living captive migratory resident populations of a songbird, dark-eyed junco, as they diverge behavior physiology during pre-breeding (spring) despite co-occurrence same environment. We report differences related including photoperiodic thresholds, endocrine profiles testosterone corticosterone, gene expression. also provide evidence genetic among based sustained when were held common conclude that existing variation likely serves migration reproduction appearance favorable environments where breeding occurs. Greater knowledge responsible allow better predictions future adaptation.

Language: Английский

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Abundance, efficiency, and stability of reference transcript expression in a seasonal rodent: The Siberian hamster

PLoS ONE, Journal Year: 2022, Volume and Issue: 17(10), P. e0275263 - e0275263

Published: Oct. 3, 2022

Quantitative PCR (qPCR) is a common molecular tool to analyse the expression of transcripts in non-traditional animal models. Most animals experience tissue-specific seasonal changes cell structure, growth, and cellular function. As consequence, choice reference or ‘house-keeping’ genes essential standardize levels target interest for qPCR analyses. This study aimed determine abundance, efficiency stability several commonly used normalisation analyses model biology: Siberian hamster ( Phodopus sungorus ). Liver, brown-adipose tissue (BAT), white adipose (WAT), testes, spleen, kidney, hypothalamic arcuate nucleus, pituitary gland from either long short photoperiod hamsters were dissected test effects on transcripts. was conducted including 18s ribosomal RNA ), glyceraldehyde 3-phosphate dehydrogenase Gapdh hypoxanthine-guanine phosphoribosyltransferase Hprt actin-β Act Cycling time (Ct), (E) replicate variation Ct E measured by percent coefficient variance (CV%) determined using miner. Measures assessed combined approach NormFinder BestKeeper. did not vary across conditions. Splenic, WAT BAT higher compared photoperiod. Splenic photoperiods. There no significant effect photoperiod, interaction measures efficiency, CV%, CV%. BestKeeper confirmed that , highly stable, while showed low stability. These findings suggest show most reliable stability, abundance tissues. Overall, provides comprehensive standardised assess multiple help inform assays studies photoperiodism.

Language: Английский

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