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An experimental test of the immunocompetence handicap hypothesis in a teleost fish: 11-ketotestosterone suppresses innate immunity in three-spined sticklebacks

Kurtz, Joachim; Kalbe, Martin; Langefors, Åsa LU and Hasselquist, Dennis LU (2007) In American Naturalist 170(4). p.509-519
Abstract
The immunocompetence handicap hypothesis (ICHH) provides a functional explanation for how sexual ornaments can provide honest signals of male quality. A key aspect of this hypothesis is that testosterone (T) has a bimodal effect: a higher T level enhances the expression of ornaments (increasing mating success and, ultimately, fitness); however, at the same time, it suppresses immune function. Tests of the latter assumption, which have focused mainly on aspects of adaptive immunity in birds, led to equivocal results. We performed a hormone‐implant experiment in male three‐spined sticklebacks (Gasterosteus aculeatus) to test the key assumptions of the ICHH in a fish, where the dominant circulating androgen is 11‐ketotestosterone (11kT)... (More)
The immunocompetence handicap hypothesis (ICHH) provides a functional explanation for how sexual ornaments can provide honest signals of male quality. A key aspect of this hypothesis is that testosterone (T) has a bimodal effect: a higher T level enhances the expression of ornaments (increasing mating success and, ultimately, fitness); however, at the same time, it suppresses immune function. Tests of the latter assumption, which have focused mainly on aspects of adaptive immunity in birds, led to equivocal results. We performed a hormone‐implant experiment in male three‐spined sticklebacks (Gasterosteus aculeatus) to test the key assumptions of the ICHH in a fish, where the dominant circulating androgen is 11‐ketotestosterone (11kT) rather than T. Males were implanted with 11‐ketoandrostenedione, which is a natural precursor of 11kT. Each individual's circulating 11kT level, ornamentation, and immunocompetence were measured 2 weeks later. In addition, we quantified oxidative tissue damage because the ICHH has been hypothesized to work via oxidative stress. We found that the males' 11kT levels correlated positively with ornamentation but negatively with immunocompetence, in particular, measures of innate immunity. Moreover, there was a trend for fish with high 11kT levels to suffer more from oxidative stress. Thus, our data provide support for the ICHH. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
oxidative stress, innate immunity, immunocompetence handicap, 11‐ketotestosterone, sexual selection, teleost fish.
in
American Naturalist
volume
170
issue
4
pages
509 - 519
publisher
University of Chicago Press
external identifiers
  • scopus:34948879122
ISSN
0003-0147
DOI
10.1086/521316
language
English
LU publication?
yes
id
7ddbed0a-52f8-47dd-b2a2-0ef2156cb216 (old id 787037)
date added to LUP
2008-01-02 19:29:52
date last changed
2017-11-19 03:34:35
@article{7ddbed0a-52f8-47dd-b2a2-0ef2156cb216,
  abstract     = {The immunocompetence handicap hypothesis (ICHH) provides a functional explanation for how sexual ornaments can provide honest signals of male quality. A key aspect of this hypothesis is that testosterone (T) has a bimodal effect: a higher T level enhances the expression of ornaments (increasing mating success and, ultimately, fitness); however, at the same time, it suppresses immune function. Tests of the latter assumption, which have focused mainly on aspects of adaptive immunity in birds, led to equivocal results. We performed a hormone‐implant experiment in male three‐spined sticklebacks (Gasterosteus aculeatus) to test the key assumptions of the ICHH in a fish, where the dominant circulating androgen is 11‐ketotestosterone (11kT) rather than T. Males were implanted with 11‐ketoandrostenedione, which is a natural precursor of 11kT. Each individual's circulating 11kT level, ornamentation, and immunocompetence were measured 2 weeks later. In addition, we quantified oxidative tissue damage because the ICHH has been hypothesized to work via oxidative stress. We found that the males' 11kT levels correlated positively with ornamentation but negatively with immunocompetence, in particular, measures of innate immunity. Moreover, there was a trend for fish with high 11kT levels to suffer more from oxidative stress. Thus, our data provide support for the ICHH.},
  author       = {Kurtz, Joachim and Kalbe, Martin and Langefors, Åsa and Hasselquist, Dennis},
  issn         = {0003-0147},
  keyword      = {oxidative stress,innate immunity,immunocompetence handicap,11‐ketotestosterone,sexual selection,teleost fish.},
  language     = {eng},
  number       = {4},
  pages        = {509--519},
  publisher    = {University of Chicago Press},
  series       = {American Naturalist},
  title        = {An experimental test of the immunocompetence handicap hypothesis in a teleost fish: 11-ketotestosterone suppresses innate immunity in three-spined sticklebacks},
  url          = {http://dx.doi.org/10.1086/521316},
  volume       = {170},
  year         = {2007},
}