title: Death rates reflect accumulating brain damage in arthropods.
abstract: We present the results of the first quantitative, whole-lifespan study of the relationship between age-specific neurolipofuscin concentration and natural mortality rate in any organism. In a convenient laboratory animal, the African migratory locust, Locusta migratoria, we find an unusual delayed-onset neurolipofuscin accumulation pattern that is highly correlated with exponentially accelerating age-specific Gompertz-Makeham death rates in both males (r=0.93, p=0.0064) and females (r=0.97, p=0.0052). We then test the conservation of this association by aggregating the locust results with available population-specific data for a range of other terrestrial, freshwater, marine, tropical and temperate arthropods whose longevities span three orders of magnitude. This synthesis shows that the strong association between neurolipofuscin deposition and natural mortality is a phylogenetically and environmentally widespread phenomenon (r=0.96, p < 0.0001). These results highlight neurolipofuscin as a unique and outstanding integral biomarker of ageing. They also offer compelling evidence for the proposal that, in vital organs like the brain, either the accumulation of toxic garbage in the form of lipofuscin itself, or the particular molecular reactions underlying lipofuscinogenesis, including free-radical damage, are the primary events in senescence.
authors.affiliation: Department of Biology, University of Leicester, University Road, Leicester LE1 7RH, UK.
authors.forename: Duane B
authors.initials: DB
authors.lastname: Fonseca
authors.forename: Carolina L
authors.initials: CL
authors.lastname: Brancato
authors.forename: Andrew E
authors.initials: AE
authors.lastname: Prior
authors.forename: Peter M J
authors.initials: PM
authors.lastname: Shelton
authors.forename: Matt R J
authors.initials: MR
authors.lastname: Sheehy
mesh_terms: D000367:Age Factors; D000375:Aging / Q000378:metabolism*; D000704:Analysis of Variance; D000818:Animals; D001181:Arthropods / Q000378:metabolism / Q000502:physiology*; D001921:Brain / Q000378:metabolism*; D005260:Female; D008062:Lipofuscin / Q000378:metabolism*; D008136:Longevity; D008297:Male; D009026:Mortality; D010802:Phylogeny
chemical_list: D008062:Lipofuscin