Testing predictions of the oxidative stress hypothesis of aging using a novel invertebrate model of longevity: the giant clam (Tridacna derasa).
Bivalve species with exceptional longevity are newly introduced model systems in biogerontology to test evolutionarily conserved mechanisms of aging. Here, we tested predictions based on the oxidative stress hypothesis of aging using one of the tropical long-lived sessile giant clam species, the smooth giant clam (Tridacna derasa; predicted maximum life span: >100 years) and the short-lived Atlantic bay scallop (Argopecten irradians irradians; maximum life span: 2 years). The warm water-dwelling giant clams warrant attention because they challenge the commonly held view that the exceptional longevity of bivalves is a consequence of the cold water they reside in. No significant interspecific differences in production of H2O2 and O2- in the gills, heart, or adductor muscle were observed. Protein carbonyl content in gill and muscle tissues were similar in T derasa and A i irradians. In tissues of T derasa, neither basal antioxidant capacities nor superoxide dismutase and catalase activities were consistently greater than in A i irradians. We observed a positive association between longevity and resistance to mortality induced by exposure to tert-butyl hydroperoxide (TBHP). This finding is consistent with the prediction based on the oxidative stress hypothesis of aging. The findings that in tissues of T derasa, proteasome activities are significantly increased as compared with those in tissues of A i irradians warrant further studies to test the role of enhanced protein recycling activities in longevity of bivalves.
Reynolds Oklahoma Center on Aging, Department of Geriatric Medicine, University of Oklahoma HSC, 975 N. E. 10th Street – BRC 1303, Oklahoma City, Oklahoma 73104, USA. zoltan-ungvari@ouhsc.edu
Zoltan
Z
Ungvari
Anna
A
Csiszar
Danuta
D
Sosnowska
Eva E
EE
Philipp
Courtney M
CM
Campbell
Philip R
PR
McQuary
Tracy T
TT
Chow
Miguel
M
Coelho
Elizabeth S
ES
Didier
Sara
S
Gelino
Marissa A
MA
Holmbeck
Insil
I
Kim
Erik
E
Levy
William E
WE
Sonntag
Paul W
PW
Whitby
Steven N
SN
Austad
Iain
I
Ridgway
D000375:Aging / Q000502:physiology*; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D005075:Biological Evolution; D049872:Bivalvia; D002374:Catalase / Q000378:metabolism; D016166:Free Radical Scavengers / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D008017:Life Expectancy; D008136:Longevity / Q000502:physiology*; D008954:Models, Biological; D018384:Oxidative Stress / Q000502:physiology*; D050050:Protein Carbonylation; D012623:Seawater; D013045:Species Specificity; D013482:Superoxide Dismutase / Q000378:metabolism; D013696:Temperature; D014022:Tissue Survival / Q000502:physiology; D020122:tert-Butylhydroperoxide / Q000494:pharmacology*
D000975:Antioxidants; D016166:Free Radical Scavengers; D020122:tert-Butylhydroperoxide; D006861:Hydrogen Peroxide; D002374:Catalase; D013482:Superoxide Dismutase