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Birch G, Meniri M, Cant MA, Blount JD. Defence against the intergenerational cost of reproduction in males: oxidative shielding of the germline. Biol Rev Camb Philos Soc 2024; 99:70-84. [PMID: 37698166 DOI: 10.1111/brv.13012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 08/09/2023] [Accepted: 08/11/2023] [Indexed: 09/13/2023]
Abstract
Reproduction is expected to carry an oxidative cost, yet in many species breeders appear to sustain lower levels of oxidative damage compared to non-breeders. This paradox may be explained by considering the intergenerational costs of reproduction. Specifically, a reduction in oxidative damage upon transitioning to a reproductive state may represent a pre-emptive shielding strategy to protect the next generation from intergenerational oxidative damage (IOD) - known as the oxidative shielding hypothesis. Males may be particularly likely to transmit IOD, because sperm are highly susceptible to oxidative damage. Yet, the possibility of male-mediated IOD remains largely uninvestigated. Here, we present a conceptual and methodological framework to assess intergenerational costs of reproduction and oxidative shielding of the germline in males. We discuss variance in reproductive costs and expected payoffs of oxidative shielding according to species' life histories, and the expected impact on offspring fitness. Oxidative shielding presents an opportunity to incorporate intergenerational effects into the advancing field of life-history evolution.
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Affiliation(s)
- Graham Birch
- Centre for Ecology & Conservation, Faculty of Environment, Science & Economy, University of Exeter, Penryn Campus, Cornwall, TR10 9FE, UK
| | - Magali Meniri
- Centre for Ecology & Conservation, Faculty of Environment, Science & Economy, University of Exeter, Penryn Campus, Cornwall, TR10 9FE, UK
| | - Michael A Cant
- Centre for Ecology & Conservation, Faculty of Environment, Science & Economy, University of Exeter, Penryn Campus, Cornwall, TR10 9FE, UK
| | - Jonathan D Blount
- Centre for Ecology & Conservation, Faculty of Environment, Science & Economy, University of Exeter, Penryn Campus, Cornwall, TR10 9FE, UK
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2
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Martínez A, López-Rull I, Fargallo JA. To Prevent Oxidative Stress, What about Protoporphyrin IX, Biliverdin, and Bilirubin? Antioxidants (Basel) 2023; 12:1662. [PMID: 37759965 PMCID: PMC10525153 DOI: 10.3390/antiox12091662] [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: 08/03/2023] [Revised: 08/15/2023] [Accepted: 08/21/2023] [Indexed: 09/29/2023] Open
Abstract
The pigments responsible for eggshell color and patterning in birds are protoporphyrin IX (PP) and biliverdin (BV). Both are involved in the catalytic degradation of the hemo group. Bilirubin (BR), another pigment, is produced when BV is broken down. PP, BV, and BR are free radical scavengers. In this study, we theoretically investigated the antioxidant capacities of these three biological meaningful molecules using Density Functional Theory calculations. First, two antioxidant mechanisms were analyzed for PP, BV, and BR: electron transfer and Hydrogen Atom Transfer. Second, since PP and BV interact with the calcium carbonate matrix of the eggshell, we analyzed the interaction of these pigments with Ca2+ and investigated their chelate compounds. Third, we explored the pro-oxidant properties of PP and BV, which have been proposed for PP when photoactivated to the triplet state, but not for BV. Our results show that PP, BV, and BR are just as good antiradical as other important natural pigments (carotenoids). Neither the antiradical properties of PP and BV nor the UV-visible spectra change due to the presence of calcium, suggesting that the signaling function of these pigments is not affected by the link with Ca2+. Finally, we found that both PP and BV (alone and when linked to Ca2+) can transfer energy from its triplet state to molecular-oxygen-producing singlet oxygen, indicating their pro-oxidant capacity. This investigation answers important questions about the function of these pigments, which may help to understand their influence on the reproductive success of birds.
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Affiliation(s)
- Ana Martínez
- Departamento de Materiales de Baja Dimensionalidad, Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Circuito Exterior S. N., Ciudad Universitaria, Ciudad de México 04510, Mexico
| | - Isabel López-Rull
- Departamento Biología y Geología, Física y Química Inorgánica, Área de Biodiversidad y Conservación, Universidad Rey Juan Carlos, C/Tulipán s/n., 28933 Madrid, Spain;
| | - Juan A. Fargallo
- Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales-CSIC, C/José Gutiérrez Abascal 2, 28006 Madrid, Spain;
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3
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Sexually dichromatic coloration of female Iberian green lizards correlates with health state and reproductive investment. Behav Ecol Sociobiol 2020. [DOI: 10.1007/s00265-020-02915-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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4
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Rodríguez-Ruiz G, Ortega J, Cuervo JJ, López P, Salvador A, Martín J. Male rock lizards may compensate reproductive costs of an immune challenge affecting sexual signals. Behav Ecol 2020. [DOI: 10.1093/beheco/araa047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Sexual signals can be evolutionarily stable if they are condition dependent or costly to the signaler. One of these costs may be the trade-off between maintaining the immune system and the elaboration of ornaments. Experimental immune challenges in captivity show a reduction in the expression of sexual signals, but it is not clear whether these detrimental effects are important in nature and, more importantly, whether they have reproductive consequences. We designed a field experiment to challenge the immune system of wild male Carpetan rock lizards, Iberolacerta cyreni, with a bacterial antigen (lipopolysaccharide). The immune challenge decreased relative reflectance of ultraviolet structural and melanin-dependent sexual coloration in the throat and the lateral ocelli, whereas the carotenoid-dependent dorsal green coloration was not affected. Immune activation also decreased proportions of ergosterol and cholesta-5,7-dien-3-ol in femoral secretions. These results support a trade-off between the immune system and both visual and chemical sexual ornaments. Moreover, the reproductive success of males, estimated with DNA microsatellites, depended on the expression of some color and chemical traits. However, the immune challenge did not cause overall differences in reproductive success, although it increased with body size/age in control but not in challenged males. This suggests the use of alternative reproductive strategies (e.g., forced matings) in challenged males, particularly in smaller ones. These males might consider that their survival probabilities are low and increase reproductive effort as a form of terminal investment in spite of their “low-quality” sexual signals and potential survival costs.
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Affiliation(s)
- Gonzalo Rodríguez-Ruiz
- Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales, CSIC, José Gutiérrez Abascal 2, Madrid, Spain
| | - Jesús Ortega
- Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales, CSIC, José Gutiérrez Abascal 2, Madrid, Spain
| | - José Javier Cuervo
- Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales, CSIC, José Gutiérrez Abascal 2, Madrid, Spain
| | - Pilar López
- Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales, CSIC, José Gutiérrez Abascal 2, Madrid, Spain
| | - Alfredo Salvador
- Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales, CSIC, José Gutiérrez Abascal 2, Madrid, Spain
| | - José Martín
- Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales, CSIC, José Gutiérrez Abascal 2, Madrid, Spain
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5
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Iglesias-Carrasco M, Head ML, Cabido C. Effect of an immune challenge on the anti-predator response of the green Iberian frog (Pelophylax perezi): the influence of urban habitats. Biol J Linn Soc Lond 2018. [DOI: 10.1093/biolinnean/bly051] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Maider Iglesias-Carrasco
- Department of Evolutionay Ecology, Museo Nacional de Ciencias Naturales (MNCN-CSIC). José Madrid, Spain
- Department of Herpetology, Aranzadi Science Society. Zorroagagaina, Donostia-San Sebastián, Gipuzkoa, Spain
| | - Megan L Head
- Division of Evolution, Ecology and Genetics. Australian National University. Research School of Biology, Linnaeus Way, Acton ACT 2601. Canberra, Australia
| | - Carlos Cabido
- Department of Herpetology, Aranzadi Science Society. Zorroagagaina, Donostia-San Sebastián, Gipuzkoa, Spain
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6
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Mészáros B, Herczeg G, Bajer K, Török J, Molnár O. Effects of energy and thermoregulation time on physiological state and sexual signal in a lizard. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2018; 327:570-578. [PMID: 29377549 DOI: 10.1002/jez.2143] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 12/26/2017] [Accepted: 01/06/2018] [Indexed: 12/12/2022]
Abstract
Theory of sexual selection states that males often develop showy signals, which reduce their survival but increase their reproductive success. During mate choice, these conspicuous signals can be honest indicators of individual quality conveying information about the signaler's physiological state. Sexually selected signals are influenced by many environmental factors; however, whether signals and physiological state are affected together is rarely studied. The ultraviolet-blue throat color of male Lacerta viridis is an intra- and intersexually selected signal connected to blood parasite infection and influenced by environmental factors. The aim of this study was to experimentally investigate how ecologically relevant environmental factors affect color signal intensity and key physiological traits parallel. During the mating season, we exposed 40 adult male lizards infected with blood parasites to food and basking time treatments in a full factorial design. We measured color, amount of reactive oxygen metabolites (ROMs), hematocrit, immunocompetence, and blood parasite intensity before and after treatments. High basking time resulted in elevated immunocompetence coupled with increased ROMs. The high food treatment increased nuptial color brightness, but also increased ROMs and decreased immunocompetence. In summary, our study provides experimental evidence about environmentally induced parallel changes in an honest sexual signal and several quality-indicator physiological traits. We showed that available energy and time for high metabolism have independent and sometimes opposite effects on individual state.
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Affiliation(s)
- Boglárka Mészáros
- Behavioural Ecology Group, Department of Systematic Zoology and Ecology, Eötvös Loránd University, Budapest, Hungary
| | - Gábor Herczeg
- Behavioural Ecology Group, Department of Systematic Zoology and Ecology, Eötvös Loránd University, Budapest, Hungary
| | - Katalin Bajer
- Behavioural Ecology Group, Department of Systematic Zoology and Ecology, Eötvös Loránd University, Budapest, Hungary.,Laboratório de Biogeografia e Macroecologia, Universidade Federal do Rio Grande do Norte Centro de Biociências, Departamento de Botânica, Ecologia e Zoologia, Campus Universitário, Lagoa Nova, Natal-RN, Brazil
| | - János Török
- Behavioural Ecology Group, Department of Systematic Zoology and Ecology, Eötvös Loránd University, Budapest, Hungary
| | - Orsolya Molnár
- Behavioural Ecology Group, Department of Systematic Zoology and Ecology, Eötvös Loránd University, Budapest, Hungary.,Laboratório de Biogeografia e Macroecologia, Universidade Federal do Rio Grande do Norte Centro de Biociências, Departamento de Botânica, Ecologia e Zoologia, Campus Universitário, Lagoa Nova, Natal-RN, Brazil
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7
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García-Roa R, Megía-Palma R, Ortega J, Jara M, López P, Martín J. Interpopulational and seasonal variation in the chemical signals of the lizard Gallotia galloti. PeerJ 2017; 5:e3992. [PMID: 29230352 PMCID: PMC5721911 DOI: 10.7717/peerj.3992] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 10/15/2017] [Indexed: 11/20/2022] Open
Abstract
Communicative traits are strikingly diverse and may vary among populations of the same species. Within a population, these traits may also display seasonal variation. Chemical signals play a key role in the communication of many taxa. However, we still know far too little about chemical communication in some vertebrate groups. In lizards, only a few studies have examined interpopulational variation in the composition of chemical cues and signals and only one study has explored the seasonal effects. Here we sampled three subspecies of the Tenerife lizards (Gallotia galloti) and analyze the lipophilic fraction of their femoral gland secretions to characterize the potential interpopulational variation in the chemical signals. In addition, we assessed whether composition of these secretions differed between the reproductive and the non-reproductive season. We analyzed variations in both the overall chemical profile and the abundance of the two main compounds (cholesterol and vitamin E). Our results show interpopulational and seasonal differences in G. gallotia chemical profiles. These findings are in accordance with the high interpopulational variability of compounds observed in lizard chemical signals and show that their composition is not only shaped by selective factors linked to reproductive season.
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Affiliation(s)
- Roberto García-Roa
- Department of Evolutionary Ecology, National Museum of Natural Sciences (MNCN-CSIC), Madrid, Spain
| | - Rodrigo Megía-Palma
- Department of Evolutionary Ecology, National Museum of Natural Sciences (MNCN-CSIC), Madrid, Spain
| | - Jesús Ortega
- Department of Evolutionary Ecology, National Museum of Natural Sciences (MNCN-CSIC), Madrid, Spain
| | - Manuel Jara
- Laboratory of Evolutionary Ecology of Adaptations, School of Life Sciences, University of Lincoln, Lincoln, United Kingdom
| | - Pilar López
- Department of Evolutionary Ecology, National Museum of Natural Sciences (MNCN-CSIC), Madrid, Spain
| | - José Martín
- Department of Evolutionary Ecology, National Museum of Natural Sciences (MNCN-CSIC), Madrid, Spain
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8
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Kopena R, López P, Martín J. Immune challenged male Iberian green lizards may increase the expression of some sexual signals if they have supplementary vitamin E. Behav Ecol Sociobiol 2017. [DOI: 10.1007/s00265-017-2401-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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9
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Tylan C, Langkilde T. Local and systemic immune responses to different types of phytohemagglutinin in the green anole: Lessons for field ecoimmunologists. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2017; 327:322-332. [PMID: 29356446 DOI: 10.1002/jez.2108] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 08/13/2017] [Accepted: 08/21/2017] [Indexed: 01/15/2023]
Abstract
The phytohemagglutinin (PHA) skin test is commonly used by ecologists to assess cell-mediated immune function of wild animals. It can be performed quickly and easily in the field, involving injection of PHA and measurement of the resultant swelling. There are multiple formulations of PHA used in ecological studies, with potentially differing outcomes that could produce inconsistent results. We tested two common types of PHA in the green anole (Anolis carolinensis) to identify local and systemic immune responses underlying the resultant swelling at 6, 18, 24, and 48 hr post injection. There were differences in both local (injection site) and systemic (blood) leukocyte responses to PHA-L versus PHA-P. PHA-P injection produced a greater overall increase in local heterophil count at the injection site compared with PHA-L, and this response was greatest at 6 and 24 hr post injection. Systemically, heterophil percentage was higher in the blood of PHA-P- versus PHA-L-injected anoles at 24 hr post injection; the time point at which heterophil percentage peaked in PHA-P-injected anoles. These results indicate that although both PHA types are effective tests of immune function in green anoles, the PHA-P swelling response invokes a much stronger heterophilic response. PHA-L is a more specific test of lymphocyte function, particularly at 24 hr post injection, making it preferable for ecoimmunology studies.
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Affiliation(s)
- Catherine Tylan
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Tracy Langkilde
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, USA.,Intercollege Graduate Degree Program in Ecology, The Center for Brain, Behavior and Cognition, The Pennsylvania State University, University Park, Pennsylvania, USA
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10
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García-Roa R, Sáiz J, Gómara B, López P, Martín J. Dietary constraints can preclude the expression of an honest chemical sexual signal. Sci Rep 2017; 7:6073. [PMID: 28729717 PMCID: PMC5519758 DOI: 10.1038/s41598-017-06323-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 06/12/2017] [Indexed: 11/19/2022] Open
Abstract
Identifying the factors that underlie signal divergences remains challenging in studies of animal communication. Regarding the chemical signalling, different compounds can be found in some species but be absent in others. We hypothesized that if the costs that are associated with the expression of some compounds are too high, their presence in the signal may be restricted. However, these compounds may be expressed and be functional when those costs are relaxed. Vitamin E (α-tocopherol), a dietary compound with metabolic relevancy, acts as an honest chemical sexual signal in many lizards but no in others such as the Carpetan Rock lizard (Iberolacerta cyreni). We investigated whether dietary supplementation favours the expression of this vitamin in scents of I. cyreni. We show that dietary constraints can preclude the expression of vitamin E in chemical secretions of wild males because was expressed when it was experimentally provided in the diet. Vitamin E supplementation also heightened the immune response of males and increased the interest of their scent for females, highlighting the vitamin E as a chemical sexual signal in this species. We suggest that diet could decisively act as a driver of intra- and interspecific divergences in the chemical signalling of lizards.
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Affiliation(s)
- Roberto García-Roa
- Department of Evolutionary Ecology, National Museum of Natural Sciences, Spanish Research Council (MNCN- CSIC), José Gutiérrez Abascal, 2, 28006, Madrid, Spain.
| | - Jorge Sáiz
- Department of Instrumental Analysis and Environmental Chemistry, Spanish Research Council (IQOG- CSIC), Juan de la Cierva, 3, 28006, Madrid, Spain
| | - Belén Gómara
- Department of Instrumental Analysis and Environmental Chemistry, Spanish Research Council (IQOG- CSIC), Juan de la Cierva, 3, 28006, Madrid, Spain
| | - Pilar López
- Department of Evolutionary Ecology, National Museum of Natural Sciences, Spanish Research Council (MNCN- CSIC), José Gutiérrez Abascal, 2, 28006, Madrid, Spain
| | - José Martín
- Department of Evolutionary Ecology, National Museum of Natural Sciences, Spanish Research Council (MNCN- CSIC), José Gutiérrez Abascal, 2, 28006, Madrid, Spain
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11
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Urban habitats can affect body size and body condition but not immune response in amphibians. Urban Ecosyst 2017. [DOI: 10.1007/s11252-017-0685-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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12
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Megía-Palma R, Martínez J, Merino S. Manipulation of parasite load induces significant changes in the structural-based throat color of male iberian green lizards. Curr Zool 2017; 64:293-302. [PMID: 30402070 PMCID: PMC6007217 DOI: 10.1093/cz/zox036] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 05/12/2017] [Indexed: 11/16/2022] Open
Abstract
The honesty of structural-based ornaments is controversial. Sexual selection theory predicts that the honesty of a sexual signal relies on its cost of production or maintenance. Therefore, environmental factors with negative impact on individuals could generate high costs and affect the expression of these sexual signals. In this sense, parasites are a main cost for their hosts. To probe the effect of parasites on the structural-based coloration of a lacertid species Lacerta schreiberi, we have experimentally removed ticks from a group of male Iberian green lizards using an acaricide treatment (i.e., the broad-use insecticide fipronil). All individuals were radio-tracked and recaptured after 15 days to study changes in coloration in both the ultraviolet (UV)-blue (structural-based) and UV-yellow (structural and pigment-based) ornamentations after manipulation, as well as changes in endo- and ectoparasitic load and body condition. Additionally, after the experiment, we measured the skin inflammatory response to a mitogen. The fipronil treatment was effective in reducing ticks and it was associated with a significant reduction of hemoparasite load. Throughout the season, individuals treated with fipronil tended to maintain the brightness of the UV-blue throat coloration while control lizards tended to increase it. However, individuals treated with fipronil that were not infected with hemoparasites significantly reduced the brightness of the UV-blue throat coloration. Individuals with a higher initial tick load exhibited a lower UV saturation increment (UV-blue) and a higher brightness increment (UV-yellow) during the experiment. Overall these results experimentally support the idea that parasites adversely influence the expression of the structural-based coloration of male Iberian green lizards. This adds evidence to the hypothesis that sexual ornaments in lizards function as honest signals.
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Affiliation(s)
- Rodrigo Megía-Palma
- Dept Ecología Evolutiva, Museo Nacional de Ciencias Naturales-CSIC, J. Gutiérrez Abascal 2, E-28006, Madrid, Spain
| | - Javier Martínez
- Área Parasitología, Dept Biomedicina y Biotecnología, Área de Parasitología. Facultad de Farmacia, Universidad de Alcalá de Henares, Alcalá de Henares, E-28871, Madrid, Spain
| | - Santiago Merino
- Dept Ecología Evolutiva, Museo Nacional de Ciencias Naturales-CSIC, J. Gutiérrez Abascal 2, E-28006, Madrid, Spain
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13
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Szuroczki D, Koprivnikar J, Baker RL. Dietary antioxidants enhance immunocompetence in larval amphibians. Comp Biochem Physiol A Mol Integr Physiol 2016; 201:182-188. [PMID: 27475300 DOI: 10.1016/j.cbpa.2016.07.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 07/22/2016] [Accepted: 07/24/2016] [Indexed: 12/20/2022]
Abstract
Dietary antioxidants have been shown to confer a variety of benefits through their ability to counter oxidative stress, including increased immunocompetence and reduced susceptibility to both infectious and non-infectious diseases. However, little is known about the effects of dietary antioxidants on immune function in larval amphibians, a group experiencing worldwide declines driven by factors that likely involve altered immunocompetence. We investigated the effects of dietary antioxidants (quercetin, vitamin E, and β-carotene) on two components of the immune system, as well as development and growth. Lithobates pipiens tadpoles fed diets with supplemental β-carotene or vitamin E exhibited an enhanced swelling response as measured with a phytohemagglutinin assay (PHA), but there was no induced antibody response. Effects were often dose-dependent, with higher antioxidant levels generally conferring stronger swelling that possibly corresponds to the innate immune response. Our results indicate that the antioxidant content of the larval amphibian diets not only had a detectable effect on their immune response capability, but also promoted tadpole growth (mass gain), although developmental stage was not affected. Given that many environmental perturbations may cause oxidative stress or reduce immunocompetence, it is critical to understand how nutrition may counter these effects.
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Affiliation(s)
- Dorina Szuroczki
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario M5S 3B2, Canada.
| | - Janet Koprivnikar
- Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, ON M5B 2K3, Canada
| | - Robert L Baker
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario M5S 3B2, Canada
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