Hormesis Results in Trade-offs with Immunity
نویسندگان
چکیده
Many have argued that we may be able to extend life and improve human health through hormesis, the beneficial effects of low-level toxins and other stressors. But, studies of hormesis in model systems have not yet established whether stress-induced benefits are cost free, artifacts of inbreeding, or come with deleterious side effects. Here, we provide evidence that hormesis results in trade-offs with immunity. We find that a single topical dose of dead spores of the entomopathogenic fungus, Metarhizium robertsii, increases the longevity of the fruit fly, Drosophila melanogaster, without significant decreases in fecundity. We find that hormetic benefits of pathogen challenge are greater in lines that lack key components of antifungal immunity (Dif and Turandot M). And, in outbred fly lines, we find that topical pathogen challenge enhances both survival and fecundity, but reduces ability to fight off live infections. The results provide evidence that hormesis is manifested by stress-induced trade-offs with immunity, not cost-free benefits or artifacts of inbreeding. Our findings illuminate mechanisms underlying pathogen-induced life-history trade-offs, and indicate that reduced immune function may be an ironic side effect of the "elixirs of life."
منابع مشابه
Ethical Perspective: Five Unacceptable Trade-offs on the Path to Universal Health Coverage
This article discusses what ethicists have called “unacceptable trade-offs” in health policy choices related to universal health coverage (UHC). Since the fiscal space is constrained, trade-offs need to be made. But some trade-offs are unacceptable on the path to universal coverage. Unacceptable choices include, among other examples from low-income countries, to expand coverage for services wit...
متن کاملHormesis and trade-offs: a comment.
Single or multiple exposures to mild stress at younger ages often have positive health beneficial effects throughout life, indicating that rescue systems turned on at a young age can be effective even in old age (e.g. Le Bourg 2011). This seems to be at variance with the notion of the so-called trade-offs that due to a limitation of resources it is impossible for an organism to increase all asp...
متن کاملDefining Pathways and Trade-offs Toward Universal Health Coverage; Comment on “Ethical Perspective: Five Unacceptable Trade-offs on the Path to Universal Health Coverage”
The World Health Organization’s (WHO’s) World Health Report 2010, “Health systems financing, the path to universal coverage,” promoted universal health coverage (UHC) as an aspirational objective for country health systems. Yet, in addition to the dimensions of services and coverage, distribution of coverage in the population, and financial risk protection highlighted by the report, the conside...
متن کاملTrade-offs between reproductive coloration and innate immunity in a natural population of female sagebrush lizards, Sceloporus graciosus.
Trade-offs between immune function and reproduction are common to many organisms. Nevertheless, high energetic resources may eliminate the need for these trade-offs. In this study, we consider the effects of food availability on these trade-offs in a wild population of female sagebrush lizards (Sceloporus graciosus) during the breeding season. We manipulated food availability by supplementing s...
متن کامل