1
|
Ndithia HK, Matson KD, Muchai M, Tieleman BI. Immune function differs among tropical environments but is not downregulated during reproduction in three year-round breeding equatorial lark populations. Oecologia 2021; 197:599-614. [PMID: 34636981 PMCID: PMC8585810 DOI: 10.1007/s00442-021-05052-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 09/28/2021] [Indexed: 11/28/2022]
Abstract
Seasonal variation in immune function can be attributed to life history trade-offs, and to variation in environmental conditions. However, because phenological stages and environmental conditions co-vary in temperate and arctic zones, their separate contributions have not been determined. We compared immune function and body mass of incubating (female only), chick-feeding (female and male), and non-breeding (female and male) red-capped larks Calandrella cinerea breeding year-round in three tropical equatorial (Kenya) environments with distinct climates. We measured four immune indices: haptoglobin, nitric oxide, agglutination, and lysis. To confirm that variation in immune function between breeding (i.e., incubating or chick-feeding) and non-breeding was not confounded by environmental conditions, we tested if rainfall, average minimum temperature (Tmin), and average maximum temperature (Tmax) differed during sampling times among the three breeding statuses per location. Tmin and Tmax differed between chick-feeding and non-breeding, suggesting that birds utilized environmental conditions differently in different locations for reproduction. Immune indices did not differ between incubating, chick-feeding and non-breeding birds in all three locations. There were two exceptions: nitric oxide was higher during incubation in cool and wet South Kinangop, and it was higher during chick-feeding in the cool and dry North Kinangop compared to non-breeding birds in these locations. For nitric oxide, agglutination, and lysis, we found among-location differences within breeding stage. In equatorial tropical birds, variation in immune function seems to be better explained by among-location climate-induced environmental conditions than by breeding status. Our findings raise questions about how within-location environmental variation relates to and affects immune function.
Collapse
Affiliation(s)
- Henry K Ndithia
- Ornithology Section, Department of Zoology, National Museums of Kenya, P.O. Box 40658, Nairobi, 00100 GPO, Kenya. .,Groningen Institute for Evolutionary Life Sciences, University of Groningen, P.O. Box 11103, 9700 CC, Groningen, The Netherlands.
| | - Kevin D Matson
- Wildlife Ecology and Conservation, Environmental Sciences Group, Wageningen University, Droevendaalsesteeg 3a, 6708 PB, Wageningen, The Netherlands
| | - Muchane Muchai
- Department of Clinical Studies (Wildlife and Conservation), College of Agriculture and Veterinary Sciences, University of Nairobi, Box 30197-00100, Nairobi, Kenya
| | - B Irene Tieleman
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, P.O. Box 11103, 9700 CC, Groningen, The Netherlands
| |
Collapse
|
2
|
Paiola M, Moreira C, Hétru J, Duflot A, Pinto PIS, Scapigliati G, Knigge T, Monsinjon T. Prepubertal gonad investment modulates thymus function: evidence in a teleost fish. J Exp Biol 2021; 224:238091. [PMID: 33789987 DOI: 10.1242/jeb.238576] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 01/20/2021] [Indexed: 12/12/2022]
Abstract
Thymus plasticity following gonadectomy or sex hormone replacement has long since exemplified sex hormone effects on the immune system in mammals and, to a lesser extent, in 'lower vertebrates', including amphibians and fish. Nevertheless, the underlying physiological significances as well as the ontogenetic establishment of this crosstalk remain largely unknown. Here, we used a teleost fish, the European sea bass, Dicentrarchus labrax, to investigate: (1) whether the regulation of thymus plasticity relies on resource trade-off with somatic growth and reproductive investment and (2) if the gonad-thymus interaction takes place during gonadal differentiation and development. Because gonadal development and, supposedly, thymus function in sea bass depend on environmental changes associated with the winter season, we evaluated thymus changes (foxn1 expression, and thymocyte and T cell content) in juvenile D. labrax raised for 1 year under either constant or fluctuating photoperiod and temperature. Importantly, in both conditions, intensive gonadal development following sex differentiation coincided with a halt of thymus growth, while somatic growth continued. To the best of our knowledge, this is the first study showing that gonadal development during prepuberty regulates thymus plasticity. This finding may provide an explanation for the initiation of the thymus involution related to ageing in mammals. Comparing fixed and variable environmental conditions, our work also demonstrates that the extent of the effects on the thymus, which are related to reproduction, depend on ecophysiological conditions, rather than being directly related to sexual maturity and sex hormone levels.
Collapse
Affiliation(s)
- Matthieu Paiola
- Normandy University, FR CNRS 3730 SCALE, UMR-I 02 INERIS-URCA-ULH Environmental Stress and Aquatic Biomonitoring (SEBIO), University of Le Havre Normandy, 76600 Le Havre, France
| | - Catarina Moreira
- Normandy University, FR CNRS 3730 SCALE, UMR-I 02 INERIS-URCA-ULH Environmental Stress and Aquatic Biomonitoring (SEBIO), University of Le Havre Normandy, 76600 Le Havre, France
| | - Julie Hétru
- Normandy University, FR CNRS 3730 SCALE, UMR-I 02 INERIS-URCA-ULH Environmental Stress and Aquatic Biomonitoring (SEBIO), University of Le Havre Normandy, 76600 Le Havre, France
| | - Aurélie Duflot
- Normandy University, FR CNRS 3730 SCALE, UMR-I 02 INERIS-URCA-ULH Environmental Stress and Aquatic Biomonitoring (SEBIO), University of Le Havre Normandy, 76600 Le Havre, France
| | - Patricia I S Pinto
- Laboratory of Comparative Endocrinology and Integrative Biology, CCMAR - Centre of Marine Sciences, University of Algarve, 8005-139 Faro, Portugal
| | - Giuseppe Scapigliati
- Department for Innovation in Biological, Agro-food and Forest Systems, Tuscia University, 01100 Viterbo, Italy
| | - Thomas Knigge
- Normandy University, FR CNRS 3730 SCALE, UMR-I 02 INERIS-URCA-ULH Environmental Stress and Aquatic Biomonitoring (SEBIO), University of Le Havre Normandy, 76600 Le Havre, France
| | - Tiphaine Monsinjon
- Normandy University, FR CNRS 3730 SCALE, UMR-I 02 INERIS-URCA-ULH Environmental Stress and Aquatic Biomonitoring (SEBIO), University of Le Havre Normandy, 76600 Le Havre, France
| |
Collapse
|
3
|
LaVere AA, Hamlin HJ, Lowers RH, Parrott BB, Ezenwa VO. Associations between testosterone and immune activity in alligators depend on bacteria species and temperature. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13756] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | | | - Russell H. Lowers
- Herndon Solutions Group, LLC, NASA Environmental and Medical Contract Kennedy Space Center FL USA
| | - Benjamin B. Parrott
- Odum School of Ecology University of Georgia Athens GA USA
- Savannah River Ecology Laboratory University of Georgia Aiken SC USA
| | - Vanessa O. Ezenwa
- Odum School of Ecology University of Georgia Athens GA USA
- Department of Infectious Diseases College of Veterinary Medicine University of Georgia Athens GA USA
| |
Collapse
|
4
|
Friedman-Einat M, Seroussi E. Avian Leptin: Bird's-Eye View of the Evolution of Vertebrate Energy-Balance Control. Trends Endocrinol Metab 2019; 30:819-832. [PMID: 31699239 DOI: 10.1016/j.tem.2019.07.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 06/13/2019] [Accepted: 07/08/2019] [Indexed: 12/20/2022]
Abstract
Discovery of the satiety hormone leptin in 1994 and its characterization in mammals provided a key tool to deciphering the complex mechanism governing adipose tissue regulation of appetite and energy expenditure. Surprisingly, despite the perfectly logical notion of an energy-storing tissue announcing the amount of fat stores using leptin signaling, alternate mechanisms were chosen in bird evolution. This conclusion emerged based on the recent discovery and characterization of genuine avian leptin - after it had been assumed missing by some, and erroneously identified by others. Critical evaluation of the past and present indications of the role of leptin in Aves provides a new perspective on the evolution of energy-balance control in vertebrates; proposing a regulation strategy alternative to the adipostat mechanism.
Collapse
Affiliation(s)
- Miriam Friedman-Einat
- Department of Animal Science, Agricultural Research Organization, Volcani Center, Rishon LeTsiyon, Israel.
| | - Eyal Seroussi
- Department of Animal Science, Agricultural Research Organization, Volcani Center, Rishon LeTsiyon, Israel
| |
Collapse
|
5
|
Smyth KN, Caruso NM, Davies CS, Clutton-Brock TH, Drea CM. Social and endocrine correlates of immune function in meerkats: implications for the immunocompetence handicap hypothesis. ROYAL SOCIETY OPEN SCIENCE 2018; 5:180435. [PMID: 30225031 PMCID: PMC6124081 DOI: 10.1098/rsos.180435] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 06/25/2018] [Indexed: 06/08/2023]
Abstract
Social status can mediate effects on the immune system, with profound consequences for individual health; nevertheless, most investigators of status-related disparities in free-ranging animals have used faecal parasite burdens to proxy immune function in the males of male-dominant species. We instead use direct measures of innate immune function (complement and natural antibodies) to examine status-related immunocompetence in both sexes of a female-dominant species. The meerkat is a unique model for such a study because it is a cooperatively breeding species in which status-related differences are extreme, evident in reproductive skew, morphology, behaviour, communication and physiology, including that dominant females naturally express the greatest total androgen (androstenedione plus testosterone) concentrations. We found that, relative to subordinates, dominant animals had reduced serum bacteria-killing abilities; also, relative to subordinate females, dominant females had reduced haemolytic complement activities. Irrespective of an individual's sex or social status, androstenedione concentrations (but not body condition, age or reproductive activity) negatively predicted concurrent immunocompetence. Thus, dominant meerkats of both sexes are immunocompromised. Moreover, in female meerkats, androstenedione perhaps acting directly or via local conversion, may exert a double-edged effect of promoting dominance and reproductive success at the cost of increased parasitism and reduced immune function. Given the prominent signalling of dominance in female meerkats, these findings may relate to the immunocompetence handicap hypothesis (ICHH); however, our data would suggest that the endocrine mechanism underlying the ICHH need not be mediated solely by testosterone and might explain trade-offs in females, as well as in males.
Collapse
Affiliation(s)
- Kendra N. Smyth
- University Program in Ecology, Duke University, Durham, NC, USA
- Department of Evolutionary Anthropology, Duke University, Durham, NC, USA
- Kalahari Research Trust, Kuruman River Reserve, Van Zylsrus, Northern Cape, South Africa
| | - Nicholas M. Caruso
- Department of Biological Sciences, University of Alabama, Tuscaloosa, AL, USA
| | - Charli S. Davies
- Department of Evolutionary Anthropology, Duke University, Durham, NC, USA
- Kalahari Research Trust, Kuruman River Reserve, Van Zylsrus, Northern Cape, South Africa
| | - Tim H. Clutton-Brock
- Kalahari Research Trust, Kuruman River Reserve, Van Zylsrus, Northern Cape, South Africa
- Department of Zoology, University of Cambridge, Cambridge, UK
- Mammal Research Institute, University of Pretoria, Pretoria, South Africa
| | - Christine M. Drea
- University Program in Ecology, Duke University, Durham, NC, USA
- Department of Evolutionary Anthropology, Duke University, Durham, NC, USA
- Department of Biology, Duke University, Durham, NC, USA
- Kalahari Research Trust, Kuruman River Reserve, Van Zylsrus, Northern Cape, South Africa
| |
Collapse
|
6
|
Nowak J, Pawłowski B, Borkowska B, Augustyniak D, Drulis-Kawa Z. No evidence for the immunocompetence handicap hypothesis in male humans. Sci Rep 2018; 8:7392. [PMID: 29743556 PMCID: PMC5943526 DOI: 10.1038/s41598-018-25694-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 04/26/2018] [Indexed: 12/11/2022] Open
Abstract
The observations that testosterone might be immunosuppressive, form the basis for the immunocompetence handicap hypothesis (ICHH). According to ICHH only high-quality individuals can maintain high levels of testosterone and afford the physiological cost of hormone-derived immunosuppression. The animal and human studies that attempted to support the ICHH by precisely defined impairment of immunity associated with high testosterone levels are inconclusive. Furthermore, human studies have used only selected immune functions and varying testosterone fractions. This is the first study examining the relationship between multiple innate and adaptive immunity and serum levels of free testosterone, total testosterone, DHT and DHEA in ninety-seven healthy men. Free testosterone and marginally DHT levels were positively correlated with the strength of the influenza post-vaccination response. Total testosterone and DHEA showed no immunomodulatory properties. Our findings did not support ICHH assumptions about immunosuppressive function of androgens. In the affluent society studied here, men with higher levels of free testosterone could afford to invest more in adaptive immunity. Since the hormone-immune relationship is complex and may depend on multiple factors, including access to food resources, androgens should be treated as immunomodulators rather than implicit immunosuppressants.
Collapse
Affiliation(s)
- Judyta Nowak
- Department of Human Biology, University of Wroclaw, Kuźnicza 35, 50-138, Wrocław, Poland.
| | - Bogusław Pawłowski
- Department of Human Biology, University of Wroclaw, Kuźnicza 35, 50-138, Wrocław, Poland
| | - Barbara Borkowska
- Department of Human Biology, University of Wroclaw, Kuźnicza 35, 50-138, Wrocław, Poland
| | - Daria Augustyniak
- Institute of Genetics and Microbiology, University of Wroclaw, Przybyszewskiego 63/77, 51-148, Wrocław, Poland
| | - Zuzanna Drulis-Kawa
- Institute of Genetics and Microbiology, University of Wroclaw, Przybyszewskiego 63/77, 51-148, Wrocław, Poland
| |
Collapse
|
7
|
Smyth KN, Greene LK, Clutton-Brock T, Drea CM. Androgens predict parasitism in female meerkats: a new perspective on a classic trade-off. Biol Lett 2017; 12:rsbl.2016.0660. [PMID: 28120802 DOI: 10.1098/rsbl.2016.0660] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 09/27/2016] [Indexed: 12/15/2022] Open
Abstract
The immunocompetence handicap hypothesis posits that androgens in males can be a 'double-edged sword', actively promoting reproductive success, while also negatively impacting health. Because there can be both substantial androgen concentrations in females and significant androgenic variation among them, particularly in species portraying female social dominance over males or intense female-female competition, androgens might also play a role in mediating female health and fitness. We examined this hypothesis in the meerkat (Suricata suricatta), a cooperatively breeding, social carnivoran characterized by aggressively mediated female social dominance and extreme rank-related reproductive skew. Dominant females also have greater androgen concentrations and harbour greater parasite loads than their subordinate counterparts, but the relationship between concurrent androgen concentrations and parasite burdens is unknown. We found that a female's faecal androgen concentrations reliably predicted her concurrent state of endoparasitism irrespective of her social status: parasite species richness and infection by Spirurida nematodes, Oxynema suricattae, Pseudandrya suricattae and coccidia were greater with greater androgen concentrations. Based on gastrointestinal parasite burdens, females appear to experience the same trade-off in the costs and benefits of raised androgens as do the males of many species. This trade-off presumably represents a health cost of sexual selection operating in females.
Collapse
Affiliation(s)
- Kendra N Smyth
- University Program in Ecology, Duke University, Durham NC 27708, USA .,Department of Evolutionary Anthropology, Duke University, Durham NC 27708, USA.,Kalahari Research Trust, Kuruman River Reserve, Northern Cape 8467, South Africa
| | - Lydia K Greene
- University Program in Ecology, Duke University, Durham NC 27708, USA.,Department of Evolutionary Anthropology, Duke University, Durham NC 27708, USA.,Kalahari Research Trust, Kuruman River Reserve, Northern Cape 8467, South Africa
| | - Tim Clutton-Brock
- Kalahari Research Trust, Kuruman River Reserve, Northern Cape 8467, South Africa.,Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK.,Mammal Research Institute, University of Pretoria, Pretoria 0028, South Africa
| | - Christine M Drea
- University Program in Ecology, Duke University, Durham NC 27708, USA.,Department of Evolutionary Anthropology, Duke University, Durham NC 27708, USA.,Department of Biology, Duke University, Durham NC 27708, USA.,Kalahari Research Trust, Kuruman River Reserve, Northern Cape 8467, South Africa
| |
Collapse
|
8
|
Rogovin KA, Khrushchova AM, Shekarova ON, Vasilieva NA, Vasilieva NY. Females choose gentle, but not healthy or macho males in Campbell dwarf hamsters ( Phodopus campbelli Thomas 1905). Curr Zool 2017; 63:545-554. [PMID: 29492014 PMCID: PMC5804195 DOI: 10.1093/cz/zow090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 08/11/2016] [Indexed: 11/29/2022] Open
Abstract
Androgen-dependent male sexual traits (STs) as well as immunocompetence are theoretically assumed to be key indicators of a male's quality for the mate-choosing female. We studied mate choice by sexually motivated (SM) females of Campbell's dwarf hamsters. Females chose between 2 tethered male siblings that differed in expression of STs. Males were unrelated to the female and able to contact and copulate with her. In both males, we measured sex-related morphology of body mass, mid-ventral specific skin gland, ano-genital distance, and external testicular diameter. We also estimated levels of blood testosterone and cortisol, specific T- and B-cell immune responses to antigens, as well as aggressive and sexual dominance in sibling males through additional encounter experiments with another SM female (male sibs could freely compete for the female). We found that SM females chose a partner among 2 male sibs and spent over 80% of their time on average with the preferred male compared with the non-preferred one. Her choice was not associated with the first visit of the chosen male, with a higher expression of sex-related traits, higher levels of blood testosterone, or with aggressive dominance. The choice was not associated with the intensity of T-cell immune response to phitohemagglutinin (PHA). Instead there was a tendency for a negative relationship with the expression of STs and B-cell response to the antigen challenge. The only character that unambiguously influenced female choice was the non-aggressive male to female grooming during sexual contact. There was no difference in breeding success between preferred and non-preferred males paired with virgin females.
Collapse
Affiliation(s)
- Konstantin A. Rogovin
- A.N. Severtsov Institute of Ecology and Evolution, RAS, Leninskii prospect 33, Moscow 119071, Russia
| | - Anastasiya M. Khrushchova
- A.N. Severtsov Institute of Ecology and Evolution, RAS, Leninskii prospect 33, Moscow 119071, Russia
| | - Olga N. Shekarova
- A.N. Severtsov Institute of Ecology and Evolution, RAS, Leninskii prospect 33, Moscow 119071, Russia
| | - Nina A. Vasilieva
- A.N. Severtsov Institute of Ecology and Evolution, RAS, Leninskii prospect 33, Moscow 119071, Russia
| | - Nina Yu Vasilieva
- A.N. Severtsov Institute of Ecology and Evolution, RAS, Leninskii prospect 33, Moscow 119071, Russia
| |
Collapse
|
9
|
Verburg-van Kemenade BML, Cohen N, Chadzinska M. Neuroendocrine-immune interaction: Evolutionarily conserved mechanisms that maintain allostasis in an ever-changing environment. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2017; 66:2-23. [PMID: 27296493 DOI: 10.1016/j.dci.2016.05.015] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 05/23/2016] [Accepted: 05/23/2016] [Indexed: 05/02/2023]
Abstract
It has now become accepted that the immune system and neuroendocrine system form an integrated part of our physiology. Immunological defense mechanisms act in concert with physiological processes like growth and reproduction, energy intake and metabolism, as well as neuronal development. Not only are psychological and environmental stressors communicated to the immune system, but also, vice versa, the immune response and adaptation to a current pathogen challenge are communicated to the entire body, including the brain, to evoke adaptive responses (e.g., fever, sickness behavior) that ensure allocation of energy to fight the pathogen. This phenomenon is evolutionarily conserved. Hence it is both interesting and important to consider the evolutionary history of this bi-directional neuroendocrine-immune communication to reveal phylogenetically ancient or relatively recently acquired mechanisms. Indeed, such considerations have already disclosed an extensive "common vocabulary" of information pathways as well as molecules and their receptors used by both the neuroendocrine and immune systems. This review focuses on the principal mechanisms of bi-directional communication and the evidence for evolutionary conservation of the important physiological pathways involved.
Collapse
Affiliation(s)
- B M Lidy Verburg-van Kemenade
- Cell Biology and Immunology Group, Dept. of Animal Sciences, Wageningen University, P.O. Box 338, 6700 AH Wageningen, The Netherlands.
| | - Nicholas Cohen
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14620, USA
| | - Magdalena Chadzinska
- Department of Evolutionary Immunology, Institute of Zoology, Jagiellonian University, Gronostajowa 9, PL30-387 Krakow, Poland
| |
Collapse
|
10
|
Procaccini C, La Rocca C, Carbone F, De Rosa V, Galgani M, Matarese G. Leptin as immune mediator: Interaction between neuroendocrine and immune system. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2017; 66:120-129. [PMID: 27288847 DOI: 10.1016/j.dci.2016.06.006] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 05/27/2016] [Accepted: 06/07/2016] [Indexed: 06/06/2023]
Abstract
Leptin is an adipocyte-derived hormone/cytokine that links nutritional status with neuroendocrine and immune functions. Initially described as an anti-obesity hormone, leptin has subsequently been shown to exert pleiotropic effects, being also able to influence haematopoiesis, thermogenesis, reproduction, angiogenesis, and more importantly immune homeostasis. As a cytokine, leptin can affect both innate and adaptive immunity, by inducing a pro-inflammatory response and thus playing a key role in the regulation of the pathogenesis of several autoimmune/inflammatory diseases. In this review, we discuss the most recent advances on the role of leptin as immune-modulator in mammals and we also provide an overview on its main functions in non-mammalian vertebrates.
Collapse
Affiliation(s)
- Claudio Procaccini
- Laboratorio di Immunologia, Istituto di Endocrinologia e Oncologia Sperimentale, Consiglio Nazionale delle Ricerche (IEOS-CNR), c/o Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli "Federico II", 80131 Napoli, Italy
| | - Claudia La Rocca
- Laboratorio di Immunologia, Istituto di Endocrinologia e Oncologia Sperimentale, Consiglio Nazionale delle Ricerche (IEOS-CNR), c/o Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli "Federico II", 80131 Napoli, Italy
| | - Fortunata Carbone
- Laboratorio di Immunologia, Istituto di Endocrinologia e Oncologia Sperimentale, Consiglio Nazionale delle Ricerche (IEOS-CNR), c/o Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli "Federico II", 80131 Napoli, Italy
| | - Veronica De Rosa
- Laboratorio di Immunologia, Istituto di Endocrinologia e Oncologia Sperimentale, Consiglio Nazionale delle Ricerche (IEOS-CNR), c/o Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli "Federico II", 80131 Napoli, Italy; Unità di NeuroImmunologia, Fondazione Santa Lucia, 00143 Roma, Italy
| | - Mario Galgani
- Laboratorio di Immunologia, Istituto di Endocrinologia e Oncologia Sperimentale, Consiglio Nazionale delle Ricerche (IEOS-CNR), c/o Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli "Federico II", 80131 Napoli, Italy
| | - Giuseppe Matarese
- Laboratorio di Immunologia, Istituto di Endocrinologia e Oncologia Sperimentale, Consiglio Nazionale delle Ricerche (IEOS-CNR), c/o Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli "Federico II", 80131 Napoli, Italy; Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli "Federico II", 80131 Napoli, Italy.
| |
Collapse
|
11
|
Abstract
Multidirectional interactions among the immune, endocrine, and nervous systems have been demonstrated in humans and non-human animal models for many decades by the biomedical community, but ecological and evolutionary perspectives are lacking. Neuroendocrine-immune interactions can be conceptualized using a series of feedback loops, which culminate into distinct neuroendocrine-immune phenotypes. Behavior can exert profound influences on these phenotypes, which can in turn reciprocally modulate behavior. For example, the behavioral aspects of reproduction, including courtship, aggression, mate selection and parental behaviors can impinge upon neuroendocrine-immune interactions. One classic example is the immunocompetence handicap hypothesis (ICHH), which proposes that steroid hormones act as mediators of traits important for female choice while suppressing the immune system. Reciprocally, neuroendocrine-immune pathways can promote the development of altered behavioral states, such as sickness behavior. Understanding the energetic signals that mediate neuroendocrine-immune crosstalk is an active area of research. Although the field of psychoneuroimmunology (PNI) has begun to explore this crosstalk from a biomedical standpoint, the neuroendocrine-immune-behavior nexus has been relatively underappreciated in comparative species. The field of ecoimmunology, while traditionally emphasizing the study of non-model systems from an ecological evolutionary perspective, often under natural conditions, has focused less on the physiological mechanisms underlying behavioral responses. This review summarizes neuroendocrine-immune interactions using a comparative framework to understand the ecological and evolutionary forces that shape these complex physiological interactions.
Collapse
Affiliation(s)
- Noah T Ashley
- Department of Biology, Western Kentucky University, Bowling Green, KY 42101, USA.
| | - Gregory E Demas
- Department of Biology, Center for the Integrative Study of Animal Behavior - Program in Neuroscience, Indiana University, Bloomington, IN 47405, USA
| |
Collapse
|
12
|
Roney JR. Theoretical frameworks for human behavioral endocrinology. Horm Behav 2016; 84:97-110. [PMID: 27320181 DOI: 10.1016/j.yhbeh.2016.06.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Revised: 06/05/2016] [Accepted: 06/07/2016] [Indexed: 10/21/2022]
Abstract
How can we best discover the ultimate, evolved functions of endocrine signals within the field of human behavioral endocrinology? Two related premises will guide my proposed answer. First, hormones typically have multiple, simultaneous effects distributed throughout the brain and body, such that in an abstract sense their prototypical function is the coordination of diverse outcomes. Second, coordinated output effects are often evolved, functional responses to specific eliciting conditions that cause increases or decreases in the relevant hormones. If we accept these premises, then a natural way to study hormones is to hypothesize and test how multiple eliciting conditions are mapped into coordinated output effects via hormonal signals. I will call these input-output mappings "theoretical frameworks." As examples, partial theoretical frameworks for gonadal hormones will be proposed, focusing on the signaling roles of testosterone in men and on estradiol and progesterone in women. Recent research on oxytocin in humans will also be considered as an example in which application of the theoretical framework approach could be especially helpful in making functional sense of the diverse array of findings associated with this hormone. The theoretical framework approach is not especially common in the current literature, with many theories having eschewed explicit consideration of input-output mappings in favor of parsimony-based arguments that attempt to find the one main thing that a hormone does with respect to psychology or behavior. I will argue that these parsimony-based models have many shortcomings, and conclude that the construction and testing of theoretical frameworks provides a better means of discovering the evolved functions of human endocrine signals.
Collapse
Affiliation(s)
- James R Roney
- Department of Psychological and Brain Sciences, University of California, Santa Barbara, CA 93106-9660, United States.
| |
Collapse
|
13
|
Foo YZ, Nakagawa S, Rhodes G, Simmons LW. The effects of sex hormones on immune function: a meta-analysis. Biol Rev Camb Philos Soc 2016; 92:551-571. [DOI: 10.1111/brv.12243] [Citation(s) in RCA: 220] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 10/30/2015] [Accepted: 11/06/2015] [Indexed: 11/30/2022]
Affiliation(s)
- Yong Zhi Foo
- ARC Centre of Excellence in Cognition and its Disorders, School of Psychology, University of Western Australia; 35 Stirling Hwy Crawley Western Australia 6009 Australia
- Centre for Evolutionary Biology, School of Animal Biology, University of Western Australia; 35 Stirling Hwy Crawley Western Australia 6009 Australia
| | - Shinichi Nakagawa
- Department of Zoology; University of Otago; 340 Great King Street Dunedin 9016 New Zealand
- Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales; UNSW Sydney NSW 2052 Australia
| | - Gillian Rhodes
- ARC Centre of Excellence in Cognition and its Disorders, School of Psychology, University of Western Australia; 35 Stirling Hwy Crawley Western Australia 6009 Australia
| | - Leigh W. Simmons
- ARC Centre of Excellence in Cognition and its Disorders, School of Psychology, University of Western Australia; 35 Stirling Hwy Crawley Western Australia 6009 Australia
- Centre for Evolutionary Biology, School of Animal Biology, University of Western Australia; 35 Stirling Hwy Crawley Western Australia 6009 Australia
| |
Collapse
|
14
|
Desprat JL, Lengagne T, Dumet A, Desouhant E, Mondy N. Immunocompetence handicap hypothesis in tree frog: trade-off between sexual signals and immunity? Behav Ecol 2015. [DOI: 10.1093/beheco/arv057] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
|
15
|
Zhang T, He H. Test of immunocompetence handicap hypothesis in mice (Mus musculus) infected with Trichinella spiralis. CAN J ZOOL 2014. [DOI: 10.1139/cjz-2014-0093] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The immunocompetence handicap hypothesis (ICHH) proposes that testosterone enhances the expression of sexual traits but suppresses immune function. However, studies to test the hypothesis have shown mixed results. Alternatively, sexual traits, immune function, and parasite susceptibility may be mediated by the stress hormone corticosterone. Here, we report an experimental test of the ICHH that included the manipulation of both testosterone and parasites in male laboratory mice (Mus musculus L., 1758). We conducted a factorial experiment, injecting each individual mouse with testosterone or not and infecting them with the nematode parasite Trichinella spiralis (Owen, 1835) or not. As predicted, testosterone enhanced the scent attractiveness of male mice, whereas parasite infection reduced it, but only in male mice not injected with testosterone. However, we found no evidence that corticosterone is involved in mediating the effects of testosterone. These results confirm that maintaining high testosterone levels entails the cost of increased parasite abundance. This study provides direct evidence supporting the ICHH.
Collapse
Affiliation(s)
- T. Zhang
- National Research Center for Wildlife Born Diseases, Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, People’s Republic of China
- College of Life Science, Graduate University of Chinese Academy of Sciences, Beijing, People’s Republic of China
| | - H. He
- National Research Center for Wildlife Born Diseases, Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, People’s Republic of China
| |
Collapse
|
16
|
Taff CC, Freeman-Gallant CR. An experimental test of the testosterone mediated oxidation handicap hypothesis in a wild bird. Horm Behav 2014; 66:276-82. [PMID: 24907452 DOI: 10.1016/j.yhbeh.2014.05.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 04/16/2014] [Accepted: 05/23/2014] [Indexed: 11/18/2022]
Abstract
The oxidation handicap hypothesis (OHH) proposed that honesty in sexual signals is maintained when testosterone simultaneously promotes the development of elaborate signals and imposes an oxidative cost. Although there is evidence that testosterone enhances display traits in some cases, relatively few studies have tested the prediction that testosterone generates oxidative costs. We tested this prediction experimentally by administering testosterone (n=14) and control (n=14) implants to free-living common yellowthroat warblers (Geothlypis trichas) and quantifying testosterone and oxidative state before and 35±15days after implantation. We interpreted our experimental results in the context of a larger database of 83 unmanipulated males observed over five breeding seasons. In our observational data, testosterone was related to aspects of the carotenoid-based bib, but these relationships were age-dependent. Bib coloration was related to testosterone only for first time breeders, while bib size was positively and negatively associated with testosterone among experienced and inexperienced breeders, respectively. Two measures of oxidative metabolism-damage to DNA and total antioxidant capacity (TAC)-were unrelated to endogenous testosterone. Despite the correlation between endogenous testosterone and plumage, our experimental results failed to support the key prediction of the OHH. Testosterone treated males had higher levels of TAC upon recapture, but oxidative damage to DNA did not differ from controls. Because antioxidants can protect against the harmful effects of oxidative stress, one interpretation of our results is that males physiologically compensated for elevated testosterone, avoiding the honesty enforcing mechanism of the OHH. Taken together, our results suggest that testosterone is not a direct mediator of honest signaling in yellowthroats via its effects on oxidative stress.
Collapse
Affiliation(s)
- Conor C Taff
- Department of Evolution & Ecology and Animal Behavior Graduate Group, University of California-Davis, USA.
| | | |
Collapse
|
17
|
O'Neal DM. Eco-endo-immunology across avian life history stages. Gen Comp Endocrinol 2013; 190:105-11. [PMID: 23707379 DOI: 10.1016/j.ygcen.2013.05.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 05/10/2013] [Accepted: 05/13/2013] [Indexed: 11/28/2022]
Abstract
Broadly distributed songbirds, particularly those that migrate, encounter a wide range of pathogens. Both pathogen exposure and energy available for immune responses are expected to be affected by environmental variation in climate, habitat quality, and social interactions as well as hormonal mechanisms. Comparisons of Aves in the field have begun to build the framework for understanding how such environmental variation interacts with disease environments as reflected in endocrine and immune responses. In this review, the roles of hormones and immune function across the various life history stages that make up the avian annual cycle are considered with an emphasis on free-living songbirds and the various hormones known to mediate the innate and acquired immune systems including melatonin, prolactin, growth hormone, and several neuroendocrine hormones. Finally, hormone-immune interactions are considered within the framework of disease ecology.
Collapse
Affiliation(s)
- Dawn M O'Neal
- Huyck Preserve and Biological Research Station, P.O. Box 189, Rensselaerville, NY 12147, USA.
| |
Collapse
|
18
|
Carlton ED, Demas GE, French SS. Leptin, a neuroendocrine mediator of immune responses, inflammation, and sickness behaviors. Horm Behav 2012; 62:272-9. [PMID: 22561456 DOI: 10.1016/j.yhbeh.2012.04.010] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 04/05/2012] [Accepted: 04/18/2012] [Indexed: 01/27/2023]
Abstract
Effective immune responses are coordinated by interactions among the nervous, endocrine, and immune systems. Mounting immune, inflammatory, and sickness responses requires substantial energetic investments, and as such, an organism may need to balance energy allocation to these processes with the energetic demands of other competing physiological systems. The metabolic hormone leptin appears to be mediating trade-offs between the immune system and other physiological systems through its actions on immune cells and the brain. Here we review the evidence in both mammalian and non-mammalian vertebrates that suggests leptin is involved in regulating immune responses, inflammation, and sickness behaviors. Leptin has also been implicated in the regulation of seasonal immune responses, including sickness; however, the precise physiological mechanisms remain unclear. Thus, we discuss recent data in support of leptin as a mediator of seasonal sickness responses and provide a theoretical model that outlines how seasonal cues, leptin, and proinflammatory cytokines may interact to coordinate seasonal immune and sickness responses.
Collapse
Affiliation(s)
- Elizabeth D Carlton
- Department of Biology, Program in Neuroscience and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN 47405, USA.
| | | | | |
Collapse
|
19
|
Cerasale DJ, Zajac DM, Guglielmo CG. Behavioral and physiological effects of photoperiod-induced migratory state and leptin on a migratory bird, Zonotrichia albicollis: I. Anorectic effects of leptin administration. Gen Comp Endocrinol 2011; 174:276-86. [PMID: 21925179 DOI: 10.1016/j.ygcen.2011.08.025] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2010] [Revised: 08/26/2011] [Accepted: 08/30/2011] [Indexed: 11/23/2022]
Abstract
The hormone leptin is involved in the regulation of energy balance in mammals, mainly by reducing food intake and body adiposity and increasing energy expenditure. During energetically demanding periods, leptin's action is often altered to facilitate fat deposition and maintain high rates of food intake. Despite the present controversy over the existence of an avian leptin, there is evidence that a leptin receptor exists in birds and its activation influences energy intake and metabolism. However, it is unknown whether the effects of the activation of leptin receptor on energy balance are modulated during migration. We manipulated photoperiod to induce migratory behavior in captive white-throated sparrows (Zonotrichia albicollis) and injected migratory and wintering sparrows with either murine leptin or PBS for 7 days. We measured food intake, changes in body composition and foraging behavior to test if leptin's effects are altered during migratory state. Leptin decreased foraging behavior, food intake and fat mass in wintering sparrows, but had no effect on foraging behavior or food intake in migratory sparrows. Migratory sparrows injected with leptin maintained fat better than sparrows injected with PBS. Thus, sparrows' responses to leptin changed with migratory state, possibly to aid in the increase and maintenance of rates of food intake and fat deposition. We also found that long-form leptin receptor and SOCS3 were expressed in tissues of sparrows, including the hypothalamus, but their expression did not change with migratory state. Further study of the leptin receptor system and other regulators of energy balance in migratory birds will increase our understanding of the physiological mechanisms that are responsible for their ability to complete energetically demanding journeys.
Collapse
Affiliation(s)
- David J Cerasale
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA.
| | | | | |
Collapse
|
20
|
Ezenwa VO, Stefan Ekernas L, Creel S. Unravelling complex associations between testosterone and parasite infection in the wild. Funct Ecol 2011. [DOI: 10.1111/j.1365-2435.2011.01919.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
21
|
Kharwar R, Haldar C. Reproductive phase dependent daily variation in melatonin receptors (Mel1a and Mel1b), androgen receptor (AR) and lung associated immunity of Perdicula asiatica. Comp Biochem Physiol A Mol Integr Physiol 2011; 159:119-24. [DOI: 10.1016/j.cbpa.2011.02.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Revised: 02/01/2011] [Accepted: 02/02/2011] [Indexed: 11/15/2022]
|
22
|
French SS, Dearing MD, Demas GE. Leptin as a physiological mediator of energetic trade-offs in ecoimmunology: implications for disease. Integr Comp Biol 2011; 51:505-13. [PMID: 21940777 DOI: 10.1093/icb/icr019] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Organisms must distribute sufficient energy among different and often competing physiological systems. This task can become challenging, however, as resources are often limiting, resulting in energetic trade-offs. For example, energetically based trade-offs between the reproductive and immune systems are common across taxa, yet the regulatory mechanisms underlying these trade-offs remain unclear. The adipose tissue hormone leptin is an ideal candidate for the modulation of energetic trade-offs between different physiological systems as this hormone serves as a gage of fat reserves and also modulates a range of physiological activities including the reproductive and immune processes. This article presents a review of the evidence for the role of leptin as a modulator of energetic trade-offs with the immune system and suggests its importance in disease ecology. In addition, we provide a case study of the ornate tree lizard (Urosaurus ornatus), testing whether leptin is involved in mediating a well-documented influence of energy state on the trade-off between reproductive activity and immune function. Overall, the combined results suggest that leptin serves as a proximate endocrine signal of available energy to the immune system, and therefore likely to affect susceptibility to diseases.
Collapse
Affiliation(s)
- Susannah S French
- Department of Biology, Utah State University, Logan, UT 84322-5305, USA.
| | | | | |
Collapse
|
23
|
Huyghe K, Van Oystaeyen A, Pasmans F, Tadić Z, Vanhooydonck B, Van Damme R. Seasonal changes in parasite load and a cellular immune response in a colour polymorphic lizard. Oecologia 2010; 163:867-74. [PMID: 20454978 DOI: 10.1007/s00442-010-1646-9] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Accepted: 04/15/2010] [Indexed: 11/29/2022]
Abstract
Permanent colour polymorphisms may be maintained by complex interactions between physiological traits (e.g. immunity) and environmental pressures. In this study we investigate morph specific variation in parasite load and cellular immune response (induced by a Phytohaemagglutinin, PHA injection) in a colour polymorphic population of the Dalmatian wall lizard (Podarcis melisellensis), where adult males have bright white, yellow or orange throats and ventral sides. Orange males have larger heads and can bite harder than the others. To examine seasonal effects, analyses were performed at an early and late stage in the reproductive season (May and September). Infection with mites and ticks did not differ among morphs, but was more severe at the end of the reproductive season. Fewer orange individuals were infected with haemogregarines at the end of the season, but white males were always more infected (higher number of haemogregarines in their blood) than other morphs. White and yellow males showed an increased PHA response towards the end of the season, but PHA response decreased in the orange morph. Finally, across all morphs, a relationship was found between ectoparasite load and PHA response. Our study provides indications of alternative life-history strategies among colour morphs and evidence for an up-regulation of the immune function at the end of the reproductive season.
Collapse
Affiliation(s)
- Katleen Huyghe
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales-CSIC, Calle José Gutiérrez Abascal 2, 28006 Madrid, Spain.
| | | | | | | | | | | |
Collapse
|
24
|
Kordonowy LL, McMurtry JP, Williams TD. Variation in plasma leptin-like immunoreactivity in free-living European starlings (Sturnus vulgaris). Gen Comp Endocrinol 2010; 166:47-53. [PMID: 19796643 DOI: 10.1016/j.ygcen.2009.09.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2009] [Revised: 09/04/2009] [Accepted: 09/05/2009] [Indexed: 11/27/2022]
Abstract
Leptin, a protein hormone secreted by fat cells, is best known for its role as an adiposity signal; however, leptin has diverse physiological roles ranging from regulation of feeding behavior and body weight, to effects on reproduction and immune function. Although leptin has been extensively studied in mammals, the identification and function of leptin in birds remains controversial, and studies have focused on captive or domesticated species. Here, we describe changes in plasma leptin-like immunoreactivity during the reproductive and non-reproductive seasons in free-living female European starlings (Sturnus vulgaris). Plasma leptin-like immunoreactivity was high during egg-laying (27.8+/-2.4 ng/mL) and clutch completion (23.8+/-1.6 ng/mL), decreased during incubation (13.0+/-1.6 ng/mL) and chick-rearing (12.0+/-1.3 ng/mL), but was elevated again in non-breeders in November (23.7+/-1.1 ng/mL). Although there was marked and consistent variation in total body mass and body composition with breeding stage and season in this population, plasma leptin-like immunoreactivity did not parallel changes in body mass or body composition. These data suggest that the strong positive relationship between plasma leptin-like immunoreactivity and body mass reported for captive birds and mammals does not hold for free-living birds. Rather, among free-living female European starlings, variation in plasma leptin-like immunoreactivity is associated with breeding stage or seasonal variation per se, and we discuss possible mechanisms underlying this variation, focusing on ovarian function and egg production.
Collapse
Affiliation(s)
- Lauren L Kordonowy
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC, Canada V5A 1S6.
| | | | | |
Collapse
|
25
|
Zhang JX, Sun L, Zhang YH. Foxn1 Gene Knockout Suppresses Sexual Attractiveness and Pheromonal Components of Male Urine in Inbred Mice. Chem Senses 2009; 35:47-56. [DOI: 10.1093/chemse/bjp081] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
|
26
|
Alonso-Alvarez C, Pérez-Rodríguez L, Garcia JT, Viñuela J. Testosterone-mediated trade-offs in the old age: a new approach to the immunocompetence handicap and carotenoid-based sexual signalling. Proc Biol Sci 2009; 276:2093-101. [PMID: 19324780 DOI: 10.1098/rspb.2008.1891] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The immunocompetence handicap hypothesis proposes that testosterone mediates a trade-off between sexual signalling and immunocompetence in males. Such a trade-off could favour the reliability of sexual signals on the basis that testosterone required for signal expression also promotes immunosuppression. However, the immunosuppressive activity of testosterone has not been convincingly demonstrated. We propose that the optimal solution to the testosterone-mediated trade-off should change with age, explaining ambiguous results in the past. Testosterone and ageing would promote two simultaneous immunosuppressive challenges unaffordable for low-quality males. Oxidative stress, as intimately related to ageing and immunosenescence, could contribute to enhance signal reliability. In this context, traits coloured by carotenoids (yellow-red traits) could play a crucial role due to the immunostimulatory and antioxidant properties of these pigments. Here, old and middle-aged male red-legged partridges were treated with testosterone or manipulated as controls. In the presence of high-testosterone levels, middle-aged males increased both circulating carotenoid levels and colour expression, whereas their cell-mediated immunity was not significantly altered. However, in old males, neither circulating carotenoids nor sexual signalling increased when treated with testosterone, but immunosuppression was detected. The link between testosterone and carotenoids could favour the reliability of sexual signals throughout the life.
Collapse
Affiliation(s)
- C Alonso-Alvarez
- Instituto de Investigación en Recursos Cinegéticos, IREC (CSIC, UCLM, JCCM), Ronda de Toledo s/n, 13005 Ciudad Real, Spain.
| | | | | | | |
Collapse
|
27
|
Whitten PL, Turner TR. Ecological and reproductive variance in serum leptin in wild vervet monkeys. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2008; 137:441-8. [DOI: 10.1002/ajpa.20885] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
|
28
|
Ros AFH. Patterns of testosterone responsiveness and immunity in relation to competitive behavior in chicks. Horm Behav 2008; 54:234-7. [PMID: 18417128 DOI: 10.1016/j.yhbeh.2008.02.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2007] [Revised: 02/18/2008] [Accepted: 02/22/2008] [Indexed: 11/30/2022]
Affiliation(s)
- A F H Ros
- Unidade de Investigação em Eco-Etologia, Instituto Superior de Psicologia Aplicada, Rua Jardim do Tabaco 34, 1149-041 Lisboa, Portugal.
| |
Collapse
|