Castration delays aging
Posted: Fri Jul 09, 2021 3:39 pm
A new article published yesterday fits well with some of the discussion on the EA. Eighteen medical researchers have their names as authors of a large study looking at the cellular-level effects of castration of sheep. (The lead authors are in New Zealand, hence sheep.) They found cellular mechanisms that delayed aging which could explain why castrated males live longer than either intact males or females. While their research was only on sheep, the implications are fascinating. The article is open source, so you can go to the DOI site and download your own PDF copy of it.
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Sugrue, Victoria J., et al. 2021. Castration delays epigenetic aging and feminizes DNA methylation at androgen- regulated loci. eLife. https://doi.org/10.7554/eLife.64932
Abstract: In mammals, females generally live longer than males. Nevertheless, the mechanisms underpinning sex-dependent longevity are currently unclear. Epigenetic clocks are powerful biological biomarkers capable of precisely estimating chronological age and identifying novel factors influencing the aging rate using only DNA methylation data. In this study, we developed the first epigenetic clock for domesticated sheep (Ovis aries), which can predict chronological age with a median absolute error of 5.1 months. We have discovered that castrated male sheep have a decelerated aging rate compared to intact males, mediated at least in part by the removal of androgens. Furthermore, we identified several androgen-sensitive CpG dinucleotides that become progressively hypomethylated with age in intact males, but remain stable in castrated males and females. Comparable sex-specific methylation differences in MKLN1 also exist in bat skin and a range of mouse tissues that have high androgen receptor expression, indicating that it may drive androgen-dependent hypomethylation in divergent mammalian species. In characterizing these sites, we identify biologically plausible mechanisms explaining how androgens drive male- accelerated aging.
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Sugrue, Victoria J., et al. 2021. Castration delays epigenetic aging and feminizes DNA methylation at androgen- regulated loci. eLife. https://doi.org/10.7554/eLife.64932
Abstract: In mammals, females generally live longer than males. Nevertheless, the mechanisms underpinning sex-dependent longevity are currently unclear. Epigenetic clocks are powerful biological biomarkers capable of precisely estimating chronological age and identifying novel factors influencing the aging rate using only DNA methylation data. In this study, we developed the first epigenetic clock for domesticated sheep (Ovis aries), which can predict chronological age with a median absolute error of 5.1 months. We have discovered that castrated male sheep have a decelerated aging rate compared to intact males, mediated at least in part by the removal of androgens. Furthermore, we identified several androgen-sensitive CpG dinucleotides that become progressively hypomethylated with age in intact males, but remain stable in castrated males and females. Comparable sex-specific methylation differences in MKLN1 also exist in bat skin and a range of mouse tissues that have high androgen receptor expression, indicating that it may drive androgen-dependent hypomethylation in divergent mammalian species. In characterizing these sites, we identify biologically plausible mechanisms explaining how androgens drive male- accelerated aging.