Test of immunocompetence handicap hypothesis in mice (Mus musculus) infected with Trichinella spiralis

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.

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Social and endocrine correlates of immune function in meerkats: implications for the immunocompetence handicap hypothesis

Royal Society Open Science ◽

10.1098/rsos.180435 ◽

2018 ◽

Vol 5 (8) ◽

pp. 180435 ◽

Cited By ~ 1

Author(s):

Kendra N. Smyth ◽

Nicholas M. Caruso ◽

Charli S. Davies ◽

Tim H. Clutton-Brock ◽

Christine M. Drea

Keyword(s):

Immune Function ◽

Social Status ◽

Dominant Species ◽

Reproductive Activity ◽

Trade Offs ◽

Endocrine Mechanism ◽

Immunocompetence Handicap Hypothesis ◽

Handicap Hypothesis ◽

Serum Bacteria ◽

Bacteria Killing

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.

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Testosterone and oxidative stress: the oxidation handicap hypothesis

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2006.3764 ◽

2006 ◽

Vol 274 (1611) ◽

pp. 819-825 ◽

Cited By ~ 214

Author(s):

Carlos Alonso-Alvarez ◽

Sophie Bertrand ◽

Bruno Faivre ◽

Olivier Chastel ◽

Gabriele Sorci

Keyword(s):

Oxidative Stress ◽

Blood Cell ◽

Red Blood Cell ◽

Cell Resistance ◽

Secondary Sexual Traits ◽

Honest Signals ◽

Mixed Support ◽

Immunocompetence Handicap Hypothesis ◽

Handicap Hypothesis ◽

The Cost

Secondary sexual traits (SST) are usually thought to have evolved as honest signals of individual quality during mate choice. Honesty of SST is guaranteed by the cost of producing/maintaining them. In males, the expression of many SST is testosterone-dependent. The immunocompetence handicap hypothesis has been proposed as a possible mechanism ensuring honesty of SST on the basis that testosterone, in addition to its effect on sexual signals, also has an immunosuppressive effect. The immunocompetence handicap hypothesis has received mixed support. However, the cost of testosterone-based signalling is not limited to immunosuppression and might involve other physiological functions such as the antioxidant machinery. Here, we tested the hypothesis that testosterone depresses resistance to oxidative stress in a species with a testosterone-dependent sexual signal, the zebra finch. Male zebra finches received subcutaneous implants filled with flutamide (an anti-androgen) or testosterone, or kept empty (control). In agreement with the prediction, we found that red blood cell resistance to a free radical attack was the highest in males implanted with flutamide and the lowest in males implanted with testosterone. We also found that cell-mediated immune response was depressed in testosterone-treated birds, supporting the immunocompetence handicap hypothesis. The recent finding that red blood cell resistance to free radicals is negatively associated with mortality in this species suggests that benefits of sexual signalling might trade against the costs derived from oxidation.

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Enhanced reproductive toxicities induced by phthalates contaminated microplastics in male mice (Mus musculus)

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2020.124644 ◽

2021 ◽

Vol 406 ◽

pp. 124644

Author(s):

Yongfeng Deng ◽

Zehua Yan ◽

Ruqin Shen ◽

Yichao Huang ◽

Hongqiang Ren ◽

...

Keyword(s):

Mus Musculus ◽

Male Mice

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Behavioral Characterization of Wild Derived Male Mice (Mus musculus musculus) of the PWD/Ph Inbred Strain: High Exploration Compared to C57BL/6J

Behavior Genetics ◽

10.1007/s10519-004-5589-y ◽

2004 ◽

Vol 34 (6) ◽

pp. 621-630 ◽

Cited By ~ 19

Author(s):

Cathy Fernandes ◽

Lin Liu ◽

Jos� L. Paya-Cano ◽

So?a Gregorov� ◽

Ji?� Forejt ◽

...

Keyword(s):

Inbred Strain ◽

Mus Musculus ◽

Male Mice ◽

Mus Musculus Musculus ◽

Behavioral Characterization

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Noise Exposure Decreases the Number of Spermatozoa in Male Mice (Mus musculus L.) Even With Grape Seed Extract (Vitis vinifera L.) Administration

WMJ (Warmadewa Medical Journal) ◽

10.22225/wmj.5.2.1785.70-75 ◽

2020 ◽

Vol 5 (2) ◽

pp. 70-75

Author(s):

Ghestiara Siregar

Keyword(s):

Treatment Group ◽

Mus Musculus ◽

Noise Exposure ◽

Grape Seed Extract ◽

Grape Seed ◽

Seed Extract ◽

Control Group ◽

Vitis Vinifera L ◽

Not Given ◽

Male Mice

Excessive continuous noises exposure changes the male hormone system which leads to formation of oxidative stress and results in disrupt of semen quality. This condition can be reduced by the use of antioxidants. Grape seed is one of the antioxidants that contains phenol components that have Resveratrol compounds. This research aimed to observe the effect of noise exposure on the number of spermatozoa of male mice given grape seed extract. The method of the research was a post-test only control group design with research subjects of 30 male Mus musculus L. (Swiss Webster) mice divided into 5 groups: group A (treatment control) was not given noise exposure and grape seed extract, group B (negative control) was not given noise exposure and was given grape seed extract, groups C, D, E (treatment group) were given noise exposure with sequential intensities of 65 dB, 85 dB, 105 dB. The treatment was given for 33 days. The results showed that noise exposure with different intensities of 65 dB, 85 dB, 105 dB reduced the spermatozoa count of male Swiss Webster mice even with the administration of grape seed extract. One Way Anova test was used to analyze the data with p-value of 0.001. Conclusion: There were differences in spermatozoa count between the control group and the treatment group. Provision of noise exposure with a value above the threshold limit reduces the number of male Swiss Webster mice spermatozoa given with grape seed extract. Keywords: Number of Spermatozoa, Grape Seed Extract, Noise exposure

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Bioactivity of Torch Ginger Umbut Extract (Etlingera elatior) Against Heal Wounds of Mice (Mus musculus)

EKSAKTA Berkala Ilmiah Bidang MIPA ◽

10.24036/eksakta/vol21-iss2/230 ◽

2020 ◽

Vol 21 (2) ◽

pp. 124-130

Author(s):

Mhd Zalil Efendi ◽

Ramadhan Sumarmin ◽

M. Syukri Fadil

Keyword(s):

Wound Healing ◽

Adult Male ◽

Mus Musculus ◽

Male Mice ◽

Pharmacological Activities ◽

Active Compounds ◽

Randomized Design ◽

Wide Range ◽

Completely Randomized Design ◽

Etlingera Elatior

Torch ginger has a wide range of good antimicrobial, antioxidant, anticancer, larvicidal and repellent activities. Active compounds in Torch ginger that affect pharmacological activities are phenols, polyphenols, flavonoids, and terpenoids. Based on these ingredients Torch ginger can be used to heal wounds. This study aims to observe the effect of Torch ginger Umbut extract on wound healing in mice. This study hopes to add information about the effect of Torch ginger umbut extract on the healing of cuts in mice so that it can be another alternative for wound healing and can be a reference for other researchers. This study used a completely randomized design with 5 treatments and 3 replications. Tests carried out on adult male mice. The results showed that the optimal wound healing in P2 is treatment with 10% Torch ginger umbut extract which requires a range of wound healing 7-8 days. Based on these results, Torch ginger umbut extract can heal wounds.

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