Ageing, Alzheimer's, MS and Parkinson's - Ageing Flashcards
(10 cards)
What is the definition of hormesis?
Hormesis is a process in which exposure to a low level of stress or toxicity induces an adaptive beneficial effect in a cell or organism.
What are examples of hormetic stressors?
Calorie restriction, phytochemicals, exercise, cognitive stimulation, intermittent cold and heat.
How does the body respond to mild stress under hormesis?
It increases production of endogenous antioxidants and cellular quality control mechanisms.
What endogenous antioxidants are upregulated by mild stress?
Glutathione, catalase, superoxide dismutase, and phase II detoxification enzymes.
What is the role of Nrf2 in hormesis?
Nrf2 senses cellular stress and upregulates genes for endogenous antioxidants via the ARE.
What does the Nrf2-ARE pathway do?
It enhances expression of glutathione enzymes, superoxide dismutase, catalase, and phase II detox enzymes.
How do phytochemicals act as antioxidants in hormesis?
They act both directly and indirectly through the Nrf2-ARE pathway.
How do calorie restriction and exercise induce hormesis?
They deplete cellular energy which activates AMPK and sirtuins, promoting longevity.
What is the role of AMPK in hormesis?
AMPK is a pro-longevity protein activated by low cellular energy, enhancing antioxidant responses.
Who are sirtuins and what do they do?
Sirtuins (SIRT1-7) are anti-ageing proteins activated by low cellular energy that promote cell repair.
