Advanced search
1 file | 1.65 MB Add to list

Lifespan extension in Caenorhabditis elegans insulin/IGF-1 signalling mutants is supported by non-vertebrate physiological traits

Bart Braeckman (UGent) and Ineke Dhondt (UGent)
(2017) NEMATOLOGY. 19(5). p.499-508
Author
Organization
Abstract
The insulin/IGF-1 signalling (IIS) pathway connects nutrient levels to metabolism, growth and lifespan in eukaryotes ranging from yeasts to humans, including nematodes such as the genetic model organism Caenorhabditis elegans. The link between ageing and the IIS pathway has been thoroughly studied in C. elegans; upon reduced IIS signalling, a genetic survival program is activated resulting in a drastic lifespan extension. One of the components of this program is the upregulation of antioxidant activity but experiments failed to show a clear causal relation to longevity. However, oxidative damage, such as protein carbonyls, accumulates at a slower pace in long-lived C. elegans mutants with reduced IIS. This is probably not achieved by increased macroautophagy, a process that sequesters cellular components to be eliminated as protein turnover rates are slowed down in IIS mutants. The IIS mutant daf-2, bearing a mutation in the insulin/IGF-1 receptor, recapitulates the dauer survival program, including accumulation of fat and glycogen. Fat can be converted into glucose and glycogen via the glyoxylate shunt, a pathway absent in vertebrates. These carbohydrates can be used as substrates for trehalose synthesis, also absent in mammals. Trehalose, a non-reducing homodimer of glucose, stabilises intracellular components and is responsible for almost half of the lifespan extension in IIS mutants. Hence, the molecular mechanisms by which lifespan is extended under reduced IIS may differ substantially between phyla that have an active glyoxylate cycle and trehalose synthesis, such as ecdysozoans and fungi, and vertebrate species such as mammals.
Keywords
antioxidants, fat, glycogen, glyoxylate shunt, proteostasis, trehalose, LIVED DAF-2 MUTANTS, AGE-1 PI3 KINASE, C-ELEGANS, PROTEIN-TURNOVER, DAMAGE THEORY, TRANSCRIPTION FACTOR, REGULATES LONGEVITY, DIETARY RESTRICTION, OXIDATIVE DAMAGE, AUTOPHAGY GENES

Downloads

  • NEMY 3060 Braeckman.pdf
    • full text
    • |
    • open access
    • |
    • PDF
    • |
    • 1.65 MB

Citation

Please use this url to cite or link to this publication:

MLA
Braeckman, Bart, and Ineke Dhondt. “Lifespan Extension in Caenorhabditis Elegans insulin/IGF-1 Signalling Mutants Is Supported by Non-vertebrate Physiological Traits.” NEMATOLOGY 19.5 (2017): 499–508. Print.
APA
Braeckman, Bart, & Dhondt, I. (2017). Lifespan extension in Caenorhabditis elegans insulin/IGF-1 signalling mutants is supported by non-vertebrate physiological traits. NEMATOLOGY, 19(5), 499–508.
Chicago author-date
Braeckman, Bart, and Ineke Dhondt. 2017. “Lifespan Extension in Caenorhabditis Elegans insulin/IGF-1 Signalling Mutants Is Supported by Non-vertebrate Physiological Traits.” Nematology 19 (5): 499–508.
Chicago author-date (all authors)
Braeckman, Bart, and Ineke Dhondt. 2017. “Lifespan Extension in Caenorhabditis Elegans insulin/IGF-1 Signalling Mutants Is Supported by Non-vertebrate Physiological Traits.” Nematology 19 (5): 499–508.
Vancouver
1.
Braeckman B, Dhondt I. Lifespan extension in Caenorhabditis elegans insulin/IGF-1 signalling mutants is supported by non-vertebrate physiological traits. NEMATOLOGY. 2017;19(5):499–508.
IEEE
[1]
B. Braeckman and I. Dhondt, “Lifespan extension in Caenorhabditis elegans insulin/IGF-1 signalling mutants is supported by non-vertebrate physiological traits,” NEMATOLOGY, vol. 19, no. 5, pp. 499–508, 2017.
@article{8529018,
  abstract     = {The insulin/IGF-1 signalling (IIS) pathway connects nutrient levels to metabolism, growth and lifespan in eukaryotes ranging from yeasts to humans, including nematodes such as the genetic model organism Caenorhabditis elegans. The link between ageing and the IIS pathway has been thoroughly studied in C. elegans; upon reduced IIS signalling, a genetic survival program is activated resulting in a drastic lifespan extension. One of the components of this program is the upregulation of antioxidant activity but experiments failed to show a clear causal relation to longevity. However, oxidative damage, such as protein carbonyls, accumulates at a slower pace in long-lived C. elegans mutants with reduced IIS. This is probably not achieved by increased macroautophagy, a process that sequesters cellular components to be eliminated as protein turnover rates are slowed down in IIS mutants. The IIS mutant daf-2, bearing a mutation in the insulin/IGF-1 receptor, recapitulates the dauer survival program, including accumulation of fat and glycogen. Fat can be converted into glucose and glycogen via the glyoxylate shunt, a pathway absent in vertebrates. These carbohydrates can be used as substrates for trehalose synthesis, also absent in mammals. Trehalose, a non-reducing homodimer of glucose, stabilises intracellular components and is responsible for almost half of the lifespan extension in IIS mutants. Hence, the molecular mechanisms by which lifespan is extended under reduced IIS may differ substantially between phyla that have an active glyoxylate cycle and trehalose synthesis, such as ecdysozoans and fungi, and vertebrate species such as mammals.},
  author       = {Braeckman, Bart and Dhondt, Ineke},
  issn         = {1388-5545},
  journal      = {NEMATOLOGY},
  keywords     = {antioxidants,fat,glycogen,glyoxylate shunt,proteostasis,trehalose,LIVED DAF-2 MUTANTS,AGE-1 PI3 KINASE,C-ELEGANS,PROTEIN-TURNOVER,DAMAGE THEORY,TRANSCRIPTION FACTOR,REGULATES LONGEVITY,DIETARY RESTRICTION,OXIDATIVE DAMAGE,AUTOPHAGY GENES},
  language     = {eng},
  number       = {5},
  pages        = {499--508},
  title        = {Lifespan extension in Caenorhabditis elegans insulin/IGF-1 signalling mutants is supported by non-vertebrate physiological traits},
  url          = {http://dx.doi.org/10.1163/15685411-00003060},
  volume       = {19},
  year         = {2017},
}

Altmetric
View in Altmetric
Web of Science
Times cited: