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Longevity and GAPDH Stability in Bivalves and Mammals: A Convenient Marker for Comparative Gerontology and Proteostasis.

Treaster SB, Chaudhuri AR, Austad SN - PLoS ONE (2015)

Bottom Line: To confirm that GAPDH proteostasis has a broad association with longevity, we also investigated a selection of primate species ranging in maximum longevity from 22 to 122 years.To explore possible mechanisms of the exceptional stress resistance of A. islandica GAPDH we enzymatically removed post-translational glycosylation, but observed no decrease in stability.While the mechanism underlying A. islandica's exceptional stress resistance remains elusive, this research identifies an experimental system that may reveal hitherto unknown mechanisms of protein homeostasis.

View Article: PubMed Central - PubMed

Affiliation: Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America.

ABSTRACT

Background: Comparative aging studies, particularly those that include species of exceptional resistance to aging processes, can potentially illuminate novel senescence-retarding mechanisms. In recent years, protein homeostasis (proteostasis) has been implicated in fundamental aging processes. Here we further evaluate the relationship between proteostasis and longevity in a selection of bivalve mollusks and mammals with maximum longevities ranging from 3 to 507 years.

Methods & results: We experimentally examined proteostasis using glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a reporter, as it is ubiquitously expressed, highly conserved, and conveniently assayed. The ability to maintain this enzymatic function was tested with increasing concentrations of the chaotropic agent urea, revealing a robust relationship with longevity in bivalves and mice. While our shortest-lived mollusk and mouse lost all activity by 2.5 and 3.5 M urea respectively, the longest-lived mollusk species, Arctica islandica, still preserved 45% of its basal function even at 6 M urea. To confirm that GAPDH proteostasis has a broad association with longevity, we also investigated a selection of primate species ranging in maximum longevity from 22 to 122 years. They outperformed the mouse at all concentrations, but among the primates results were variable at low urea doses. Still, at 6 M urea baboon and human samples retained 10% of their activity while both mouse and marmoset samples had no activity.

Mechanism of exceptional stress resistance: To explore possible mechanisms of the exceptional stress resistance of A. islandica GAPDH we enzymatically removed post-translational glycosylation, but observed no decrease in stability. We also removed molecules smaller than 30 kDa, which includes most small heat shock proteins, but again did not compromise the exceptional stress resistance of Arctica GAPDH.

Conclusion: While the mechanism underlying A. islandica's exceptional stress resistance remains elusive, this research identifies an experimental system that may reveal hitherto unknown mechanisms of protein homeostasis.

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Related in: MedlinePlus

GAPDH Activity with Increasing Urea Stress in Mammals.Lysates from each species were pre-stressed for twenty minutes in the noted urea concentrations. Glyceraldehyde 3-phosphate was then added, and the activity of endogenous GAPDH was monitored as ΔA340/minute, corresponding to the reduction of NAD+ to NADH. Data is reported as the fold change from unstressed activity. Differences among species were assessed by two way analysis of variance indicating a significant main effect of species (F3,60 = 222.5, p < 0.0001) stress (F4,60 = 429.9, p < 0.0001), as well as the interaction between species and stress (F12,60 = 26.1, p < 0.0001). Long-lived species maintain GAPDH function at all doses tested, while shorter-lived species were dramatically compromised. Asterisks indicate significant individual differences as assessed post hoc with Tukey's HSD, p < 0.05 (*), 0.001 (**), and 0.0001(***), respectively. Numbers in parenthesis are maximum species longevity in years.
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pone.0143680.g002: GAPDH Activity with Increasing Urea Stress in Mammals.Lysates from each species were pre-stressed for twenty minutes in the noted urea concentrations. Glyceraldehyde 3-phosphate was then added, and the activity of endogenous GAPDH was monitored as ΔA340/minute, corresponding to the reduction of NAD+ to NADH. Data is reported as the fold change from unstressed activity. Differences among species were assessed by two way analysis of variance indicating a significant main effect of species (F3,60 = 222.5, p < 0.0001) stress (F4,60 = 429.9, p < 0.0001), as well as the interaction between species and stress (F12,60 = 26.1, p < 0.0001). Long-lived species maintain GAPDH function at all doses tested, while shorter-lived species were dramatically compromised. Asterisks indicate significant individual differences as assessed post hoc with Tukey's HSD, p < 0.05 (*), 0.001 (**), and 0.0001(***), respectively. Numbers in parenthesis are maximum species longevity in years.

Mentions: In order to assess each species' relative proteostasis potential, GAPDH activity was monitored under increasingly stressed conditions and quantified as the fold change from basal levels. As a representative of global proteome stability, protection of GAPDH activity was robustly correlated with longevity in both bivalves and mammals. While GAPDH in short-lived Ruditapes lost all activity by 2.5 M urea, and mouse showed negligible activity by 3.5 M urea, the exceptionally long-lived Arctica maintained 45% of its basal activity in 6 M urea (Fig 1). Long-lived mammals also performed well, with human and baboon samples maintaining 10% of their basal activity at 6 M urea (Fig 2), significantly outperforming the other, shorter-lived mammals. However, at lower doses, the shorter-lived primate's GAPDH was more stable than the human samples. At all doses the commonly used but short-lived C57Bl6 was the least stable mammal, and lost all activity by 3.5 M urea. It should be noted that the long-lived bivalves retained greater GAPDH activity relative to unstressed controls than even the human sample. This suggests that long-lived bivalves may possess more effective proteostasis mechanisms than even the longest-lived mammals.


Longevity and GAPDH Stability in Bivalves and Mammals: A Convenient Marker for Comparative Gerontology and Proteostasis.

Treaster SB, Chaudhuri AR, Austad SN - PLoS ONE (2015)

GAPDH Activity with Increasing Urea Stress in Mammals.Lysates from each species were pre-stressed for twenty minutes in the noted urea concentrations. Glyceraldehyde 3-phosphate was then added, and the activity of endogenous GAPDH was monitored as ΔA340/minute, corresponding to the reduction of NAD+ to NADH. Data is reported as the fold change from unstressed activity. Differences among species were assessed by two way analysis of variance indicating a significant main effect of species (F3,60 = 222.5, p < 0.0001) stress (F4,60 = 429.9, p < 0.0001), as well as the interaction between species and stress (F12,60 = 26.1, p < 0.0001). Long-lived species maintain GAPDH function at all doses tested, while shorter-lived species were dramatically compromised. Asterisks indicate significant individual differences as assessed post hoc with Tukey's HSD, p < 0.05 (*), 0.001 (**), and 0.0001(***), respectively. Numbers in parenthesis are maximum species longevity in years.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4664256&req=5

pone.0143680.g002: GAPDH Activity with Increasing Urea Stress in Mammals.Lysates from each species were pre-stressed for twenty minutes in the noted urea concentrations. Glyceraldehyde 3-phosphate was then added, and the activity of endogenous GAPDH was monitored as ΔA340/minute, corresponding to the reduction of NAD+ to NADH. Data is reported as the fold change from unstressed activity. Differences among species were assessed by two way analysis of variance indicating a significant main effect of species (F3,60 = 222.5, p < 0.0001) stress (F4,60 = 429.9, p < 0.0001), as well as the interaction between species and stress (F12,60 = 26.1, p < 0.0001). Long-lived species maintain GAPDH function at all doses tested, while shorter-lived species were dramatically compromised. Asterisks indicate significant individual differences as assessed post hoc with Tukey's HSD, p < 0.05 (*), 0.001 (**), and 0.0001(***), respectively. Numbers in parenthesis are maximum species longevity in years.
Mentions: In order to assess each species' relative proteostasis potential, GAPDH activity was monitored under increasingly stressed conditions and quantified as the fold change from basal levels. As a representative of global proteome stability, protection of GAPDH activity was robustly correlated with longevity in both bivalves and mammals. While GAPDH in short-lived Ruditapes lost all activity by 2.5 M urea, and mouse showed negligible activity by 3.5 M urea, the exceptionally long-lived Arctica maintained 45% of its basal activity in 6 M urea (Fig 1). Long-lived mammals also performed well, with human and baboon samples maintaining 10% of their basal activity at 6 M urea (Fig 2), significantly outperforming the other, shorter-lived mammals. However, at lower doses, the shorter-lived primate's GAPDH was more stable than the human samples. At all doses the commonly used but short-lived C57Bl6 was the least stable mammal, and lost all activity by 3.5 M urea. It should be noted that the long-lived bivalves retained greater GAPDH activity relative to unstressed controls than even the human sample. This suggests that long-lived bivalves may possess more effective proteostasis mechanisms than even the longest-lived mammals.

Bottom Line: To confirm that GAPDH proteostasis has a broad association with longevity, we also investigated a selection of primate species ranging in maximum longevity from 22 to 122 years.To explore possible mechanisms of the exceptional stress resistance of A. islandica GAPDH we enzymatically removed post-translational glycosylation, but observed no decrease in stability.While the mechanism underlying A. islandica's exceptional stress resistance remains elusive, this research identifies an experimental system that may reveal hitherto unknown mechanisms of protein homeostasis.

View Article: PubMed Central - PubMed

Affiliation: Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America.

ABSTRACT

Background: Comparative aging studies, particularly those that include species of exceptional resistance to aging processes, can potentially illuminate novel senescence-retarding mechanisms. In recent years, protein homeostasis (proteostasis) has been implicated in fundamental aging processes. Here we further evaluate the relationship between proteostasis and longevity in a selection of bivalve mollusks and mammals with maximum longevities ranging from 3 to 507 years.

Methods & results: We experimentally examined proteostasis using glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a reporter, as it is ubiquitously expressed, highly conserved, and conveniently assayed. The ability to maintain this enzymatic function was tested with increasing concentrations of the chaotropic agent urea, revealing a robust relationship with longevity in bivalves and mice. While our shortest-lived mollusk and mouse lost all activity by 2.5 and 3.5 M urea respectively, the longest-lived mollusk species, Arctica islandica, still preserved 45% of its basal function even at 6 M urea. To confirm that GAPDH proteostasis has a broad association with longevity, we also investigated a selection of primate species ranging in maximum longevity from 22 to 122 years. They outperformed the mouse at all concentrations, but among the primates results were variable at low urea doses. Still, at 6 M urea baboon and human samples retained 10% of their activity while both mouse and marmoset samples had no activity.

Mechanism of exceptional stress resistance: To explore possible mechanisms of the exceptional stress resistance of A. islandica GAPDH we enzymatically removed post-translational glycosylation, but observed no decrease in stability. We also removed molecules smaller than 30 kDa, which includes most small heat shock proteins, but again did not compromise the exceptional stress resistance of Arctica GAPDH.

Conclusion: While the mechanism underlying A. islandica's exceptional stress resistance remains elusive, this research identifies an experimental system that may reveal hitherto unknown mechanisms of protein homeostasis.

Show MeSH
Related in: MedlinePlus