title: A heart that beats for 500 years: age-related changes in cardiac proteasome activity, oxidative protein damage and expression of heat shock proteins, inflammatory factors, and mitochondrial complexes in Arctica islandica, the longest-living noncolonial animal.
abstract: Study of negligibly senescent animals may provide clues that lead to better understanding of the cardiac aging process. To elucidate mechanisms of successful cardiac aging, we investigated age-related changes in proteasome activity, oxidative protein damage and expression of heat shock proteins, inflammatory factors, and mitochondrial complexes in the heart of the ocean quahog Arctica islandica, the longest-lived noncolonial animal (maximum life span potential: 508 years). We found that in the heart of A. islandica the level of oxidatively damaged proteins did not change significantly up to 120 years of age. No significant aging-induced changes were observed in caspase-like and trypsin-like proteasome activity. Chymotrypsin-like proteasome activity showed a significant early-life decline, then it remained stable for up to 182 years. No significant relationship was observed between the extent of protein ubiquitination and age. In the heart of A. islandica, an early-life decline in expression of HSP90 and five mitochondrial electron transport chain complexes was observed. We found significant age-related increases in the expression of three cytokine-like mediators (interleukin-6, interleukin-1β, and tumor necrosis factor-α) in the heart of A. islandica. Collectively, in extremely long-lived molluscs, maintenance of protein homeostasis likely contributes to the preservation of cardiac function. Our data also support the concept that low-grade chronic inflammation in the cardiovascular system is a universal feature of the aging process, which is also manifest in invertebrates.
authors.affiliation: Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center.
authors.forename: Danuta
authors.initials: D
authors.lastname: Sosnowska
authors.affiliation: School of Ocean Sciences, Bangor University, Menai Bridge, Anglesey, UK.
authors.forename: Chris
authors.initials: C
authors.lastname: Richardson
authors.affiliation: Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center.
authors.forename: William E
authors.initials: WE
authors.lastname: Sonntag
authors.affiliation: Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center. Department of Pathophysiology and Gerontology, Medical School and Szentágothai Research Center, University of Pecs, Hungary.
authors.forename: Anna
authors.initials: A
authors.lastname: Csiszar
authors.affiliation: Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center. Department of Pathophysiology and Gerontology, Medical School and Szentágothai Research Center, University of Pecs, Hungary. zoltan-ungvari@ouhsc.edu.
authors.forename: Zoltan
authors.initials: Z
authors.lastname: Ungvari
authors.affiliation: Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center. School of Ocean Sciences, Bangor University, Menai Bridge, Anglesey, UK.
authors.forename: Iain
authors.initials: I
authors.lastname: Ridgway
mesh_terms: D000375:Aging; D000818:Animals; D016207:Cytokines / Q000096:biosynthesis*; D004797:Enzyme-Linked Immunosorbent Assay; D006360:Heat-Shock Proteins / Q000096:biosynthesis*; D008136:Longevity / Q000502:physiology*; D049891:Mercenaria / Q000502:physiology*; D008929:Mitochondria, Heart / Q000378:metabolism*; D018384:Oxidative Stress; D046988:Proteasome Endopeptidase Complex / Q000096:biosynthesis*
chemical_list: D016207:Cytokines; D006360:Heat-Shock Proteins; D046988:Proteasome Endopeptidase Complex
keywords: Cardiac.; Extreme longevity; Invertebrate; Model system; Mollusc