Work

Hyperoxia Exposure Induced Hormesis Decreases Mitochondrial Superoxide Radical Levels via Ins/IGF-1 Signaling Pathway in a Long-lived age-1 Mutant of Caenorhabditis elegans

Year: 2008

Type: article

Abstract: The hormetic effect, which extends the lifespan by various stressors, has been confirmed in Caenorhabditis elegans (C. elegans). We have previously reported that oxidative stress resistance in a long-lived mutant age-1 is associated with the hormesis. In the age-1 allele, which activates an insulin/insulin-like growth factor-1 (Ins/IGF-1) signaling pathway, the superoxide dismutase (SOD) and catalase activities increased during normal aging. We now demonstrate changes in the mitochondrial superoxide radical (*O(2)(-)) levels of the hormetic conditioned age-related strains. The *O(2)(-) levels in age-1 strain significantly decreased after intermittent hyperoxia exposure. On the other hand, this phenomenon was not observed in a daf-16 null mutant. This hormesis-dependent reduction of the *O(2)(-) levels was observed even if the mitochondrial Mn-SOD was experimentally reduced. Therefore, it is indicated that the hormesis is mediated by events that suppress the mitochondrial *O(2)(-) production. Moreover, some SOD gene expressions in the hormetic conditioned age-1 mutant were induced over steady state mRNA levels. These data suggest that oxidative stress-inducible hormesis is associated with a reduction of the mitochondrial *O(2)(-) production by activation of the antioxidant system via the Ins/IGF-1 signaling pathway.

Source: Journal of Radiation Research

DOI: 10.1269/jrr.07043

Authors: Sumino YANASE, Naoaki ISHII

Institutions: Tokai University, Daito Bunka University

Language: English

Topic: Genetics, Aging, and Longevity in Model Organisms

Subfield: Aging

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $2,430