Test 3 - Beall Flashcards
What are the hallmarks of aging as described in the lecture and the recommended reading?
- Altered intercellular communication
- Genomic instability
- Telomere attrition
- Epigenetic alterations
- Loss of proteostasis
- Deregulated nutrient sensing
- Mitochondrial dysfunction
- Cellular senescence
- Stem cell exhaustion
What are the 2 forms of Alzheimers disease that were discussed?
Amyloid plaques and Neurofibrillary tangles
What genes and proteins have been found, and what does that say about the mechanisms of disease?
Amyloid plaques - Beta-amyloid peptide (extracellular)
Neurofibrillary tangles - Tau Protein (intracellular)
More evidence for the tangle theory
What is the Hayflick limit?
It describes the fact that somatic cells have a limited ability to replicate in culture
What are telomeres?
What is telomere attrition?
Structures at the ends of chromosomes.
Chromosomes get shorter and shorter because there is no DNA for another priming event. Due to lack of telomerase.
What can explain the Hayflick limit?
Telomere attrition
What does Telomerase contain?
RNA and Reverse Transcriptase
What pathways are proposed for nutrient sensing?
IGF-1 and Insulin pathways
How can IGF-1 and Insulin pathways thought to explain the anti-aging effects of caloric restriction?
An increase in AMPK and Sirt1 by dietary restriction are believed to inhibit mTOR which is believed to stimulate an aging process
What is progeroid syndrome?
Genetic disease with premature aging
What is Werner’s and Blooms syndrome?
Mutations in DNA helicases involved in repair
What is Hutchinson-Gilford syndrome?
Mutation in prelamin A
Explain genetic instability
DNA repair activity correlates with longevity
What is the free radical theory of aging?
Free radicals induce proteins that result in AGEs and ALEs
What is the evidence against the free radical theory?
Anti-oxidants are essential, but do not extend life. If free radicals were causing aging, would anti-oxidants extend life?
