Effects of reproduction, feeding rate, and lipid peroxidation on intraspecific variation of lifespan in Daphnia.

Faculty Mentor

Lev Yampolsky

Mentor Home Department

Biological Sciences

Short Abstract

Longevity and aging studies require knowledge about intraspecific variation for lifespan for two reasons. First, we need reliable baseline (control) data in experiments that aim to measure effects of various lifespan interventions. Second, genetic and physiological determinants of longevity may allow us to elucidate mechanisms of extended lifespan. We studied longevity of 12 genotypes of Daphnia magna from different geographic locations and habitat types, measuring clone-specific feeding rate and two parameters of lipid peroxidation (LPO) – amounts of primary products of LPO in 4 different tissues and of MDA, the final product of LPO in whole body extracts. All three measured parameters changed with age, feeding rate and LPO decreasing with age, while MDA concentration increasing with age. The 12 genotypes studied significantly differed in all three parameters. However, feeding rate did not correlate with genotype-specific longevity, while LPO and MDA measurements correlated with longevity only in long-lived genotypes, but not in short-lived ones. Median lifespan was positively correlated with the LPO levels measured in all four tissues, in any age classes. This indicates that clones capable of accumulation or synthesis of polyunsaturated fatty acids, the main target of LPO tend to live longer. Lifespan was positively correlated with MDA levels observed early in life, but negatively correlated with those observed in mid-life age class (MDA * Age interaction P < 0.004). We hypothesize that this may reflect early life benefits of accumulating PUFAs, followed by detrimental effects of accumulation of toxic and mutagenic LPO products in tissues.

Category

Science, Technology and Engineering

Start Date

5-4-2024 9:10 AM

End Date

5-4-2024 10:10 AM

Location

D.P. Culp Center Room 219

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Apr 5th, 9:10 AM Apr 5th, 10:10 AM

Effects of reproduction, feeding rate, and lipid peroxidation on intraspecific variation of lifespan in Daphnia.

D.P. Culp Center Room 219

Longevity and aging studies require knowledge about intraspecific variation for lifespan for two reasons. First, we need reliable baseline (control) data in experiments that aim to measure effects of various lifespan interventions. Second, genetic and physiological determinants of longevity may allow us to elucidate mechanisms of extended lifespan. We studied longevity of 12 genotypes of Daphnia magna from different geographic locations and habitat types, measuring clone-specific feeding rate and two parameters of lipid peroxidation (LPO) – amounts of primary products of LPO in 4 different tissues and of MDA, the final product of LPO in whole body extracts. All three measured parameters changed with age, feeding rate and LPO decreasing with age, while MDA concentration increasing with age. The 12 genotypes studied significantly differed in all three parameters. However, feeding rate did not correlate with genotype-specific longevity, while LPO and MDA measurements correlated with longevity only in long-lived genotypes, but not in short-lived ones. Median lifespan was positively correlated with the LPO levels measured in all four tissues, in any age classes. This indicates that clones capable of accumulation or synthesis of polyunsaturated fatty acids, the main target of LPO tend to live longer. Lifespan was positively correlated with MDA levels observed early in life, but negatively correlated with those observed in mid-life age class (MDA * Age interaction P < 0.004). We hypothesize that this may reflect early life benefits of accumulating PUFAs, followed by detrimental effects of accumulation of toxic and mutagenic LPO products in tissues.