Week 2 - Senescence Flashcards
Explain oxidative stress
Oxidative stress occurs when there’s an imbalance between free radicals and antioxidants in the body, leading to potential cellular and tissue damage. This imbalance can contribute to various diseases, including cardiovascular, neurodegenerative, and inflammatory disorders, as well as aging.
Explain epigenetic dysregulation
Epigenetic - factors that can change your gene expression. e.g. diet, obesity, smoking, pollutants.
Dysregulation - a process in the body not controlled in the way it normally should be.
Epigenetic dysregulation - Factors changing the gene expression in individuals to be not controlled in the way they normally should be.
What are the internal and external factors that can cause cellular damage?
Cells can be damaged by external factors like sunlight or environmental chemicals, and internally by natural processes such as metabolism, inflammation.
What are the cellular responses to damage? (4)
(1) Responses include repair and return to normal function, (2) apoptosis (programmed cell death) if damage is irreparable, (3) increased cell proliferation from DNA damage potentially leading to cancer, and (4) senescence where cells no longer divide but remain metabolically active.
Who discovered the concept of senescence and when?
Leonard Hayflick and Paul Moorhead discovered the concept of senescence in the 1960s.
What are the main causes of senescence? and what exactly do these causes do to the body?
Basically - ageing, environmental toxins (e.g. UV radiation, smoking), oxidative stress, chronic inflammation
These cause telomere damage, epigenetic dysregulation, DNA damage, and mitochondrial dysfunction
What is the purpose of senescent cells?
Senescent cells serve as a cancer prevention mechanism by undergoing permanent cell cycle arrest to avoid unchecked cell proliferation.
What are the characteristics of senescent cells?
They are highly metabolically active and secrete proteins and molecules causing inflammation, known as the Senescence-Associated Secretory Phenotype (SASP), which helps recruit immune cells for damage clearance and supports tissue repair.
What are the downsides of senescence?
Excessive senescent cells can harm health, with their accumulation linked to diseases like Alzheimer’s, heart disease, and liver fibrosis due to increased inflammation.
What is being investigated in ongoing research and potential therapies regarding senescent cells?
Research focuses on the roles of senescent cells in diseases and explores removing them using drugs or cell therapies to improve health.
Senescent cell in a nutshell
Senescent cells occur through multiple modes. Usually with age or external/internal damage. This is the bodies process to prevent cancer and cell proliferation. Although, these cells are survivors and prevent the normal cell death process of apoptosis. A build up of senescence cells over-time through old age or other modes of damage can cause inflammatory diseases in the body.
Explain Phenotype
the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment.
Explain Genotype
the genetic constitution of an individual organism.
