[30] Cellular Senescence and Aging Flashcards
What is Cellular Senescence?
The state of irreversible cell cycle arrest.
What triggers Cellular Senescence?
- DNA damage
- Telomere shortening
- Oncogene activation
What role does Cellular Senescence play in Aging?
It’s believed to contribute to aging and age-related diseases due to the accumulation of senescent cells.
What is the Senescence-Associated Secretory Phenotype (SASP)?
A characteristic of senescent cells where they secrete inflammatory and tissue-remodeling molecules.
SASP - Initials
Senescence-Associated Secretory Phenotype
How does SASP affect the tissue environment?
It can stimulate inflammation and alter the behavior of nearby cells.
What role does Telomere shortening play in Cellular Senescence?
When telomeres become critically short, the DNA damage response is triggered leading to cellular senescence.
What are Telomeres?
The protective caps on the ends of chromosomes that shorten with each cell division.
How is Cellular Senescence linked to Cancer?
Senescence is a tumor suppressive mechanism, but senescent cells can also promote cancer through SASP.
What are the morphological changes in senescent cells?
- Enlarged size
- Increased granularity
- Altered gene expression
What are Senolytics?
Drugs designed to selectively kill senescent cells.
What role do Senolytics play in Aging and Age-related diseases?
They have potential to delay aging and reduce age-related diseases by eliminating accumulated senescent cells.
What are some methods to identify Senescent Cells?
- Senescence-associated beta-galactosidase staining
- Detection of DNA damage foci
- Expression of cell cycle inhibitors (p16, p21)
What is the Hayflick Limit?
The number of times a normal human cell population will divide before cell division stops, due to senescence.
What happens to the Mitochondria in senescent cells?
They often show altered function and morphology, and can contribute to the SASP.
How do Reactive Oxygen Species (ROS) contribute to Cellular Senescence?
ROS can cause DNA damage and other cellular stresses that trigger senescence.
What role does the Immune System play in Cellular Senescence?
The immune system can remove senescent cells, but its efficiency declines with age, contributing to their accumulation.
What is the connection between Cellular Senescence and Stem Cells?
Senescence of stem cells can impair tissue repair and regeneration, contributing to aging.
What are the potential therapeutic strategies targeting Cellular Senescence?
- Senolytics (to kill senescent cells)
- Immune system modulation (to enhance clearance of senescent cells)
- Modulation of SASP
What is the relationship between Cellular Senescence and Inflammation?
Senescent cells through SASP can stimulate chronic inflammation, which in turn can induce more cells to become senescent.
