Investigation of the molecular ageing process of the long-livedbivalve Arctica islandica

• Main Author: Gruber, Heike
• Other Authors: Rosenstiel, Philip, Roeder, Thomas
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: 2013
• Subjects: thesis; ddc:500; ageing; Arctica islandica; transcriptome; gene expression; ageing markers; Altern; Transkriptom; Genexpression; Alterungsmarker; Iceland
• Online Access: https://nbn-resolving.org/urn:nbn:de:gbv:8-diss-122454; https://macau.uni-kiel.de/receive/diss_mods_00012245; https://macau.uni-kiel.de/servlets/MCRFileNodeServlet/dissertation_derivate_00004871/Diss_Gruber_2013_final.pdf

The question on why we age and how ageing proceeds has occupied researchers’ minds for a long time. Demands on research of healthy ageing and geriatric diseases rise with an older growing human population. Thus, studying the mechanisms of ageing in animals with extraordinarily long lifespans could possibly reveal secrets to longevity and healthy ageing. In this study, a short-lived population of the bivalve mollusk Arctica islandica from the Baltic Sea (with a maximum lifespan – MLSP – of 40 years) was compared to a long-lived population from Iceland (MLSP >400 years) with respect to physiological and molecular damage parameters and gene expression. Both populations originate from two very distinct environments that may influence the ageing process of the animals. Cohorts of both populations were sampled in 2010 and sexes and ages of all animals were determined. Based on this data, ageing markers (oxidation of proteins, lipids, and nucleotides, protein stability, telomere length, telomerase activity) from selected individuals along sampled age ranges (10-36 years in the Baltic Sea and 6-226 years in Iceland) of the two populations were investigated. Oxidation to nucleotides significantly accumulated over age in both populations and did so significantly faster in the shorter-lived Baltic Sea compared to the longer-lived Iceland population regarding their absolute chronological age. Remarkably, when looking at the results in respect to the relative lifespan of each population, nucleotide damage accumulated at the same pace in both populations. Additionally, a significantly higher mean level of DNA damage was detected in the shorter-lived Baltic Sea population where frequent hypoxic and anoxic events occur and the animals are living in a warmer environment. Interestingly, significantly higher mean levels of lipid peroxidation were observed in the long-lived cold-adapted Iceland population that might result from a different lipid composition at colder temperatures. Lipid peroxidation over investigated ages, ...