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The somatic mutation theory of ageing states that accumulation of mutations in somatic cells is the primary cause of aging. A comparison of somatic mutation rate across several mammal species found that the total number of accumulated mutations at the end of lifespan was roughly equal across a broad range of lifespans. [ 16 ]
The immunological theory of aging suggests that the immune system weakens as an organism ages. This makes the organism unable to fight infections and less able to destroy old and neoplastic cells. This leads to aging and will eventually lead to death. This theory of aging was developed by Roy Walford in 1969.
In 1954 Vladimir Dilman proposed hypothesis of aging that at first become known only in the USSR, as the elevation hypothesis. In 1968 it took the form and became known as the neuroendocrine theory of aging. [3] [4] [5]
Also, some diseases related to hematopoietic system, such as aplastic anemia and complete bone marrow failure, are not especially age-dependent. Aplastic Anemia is often an adverse effect of certain medications [ 17 ] but as such it cannot really be considered as evidence against the stem cell theory of aging.
Aging by design theory; Aging theories based on evolvability; Aging theories based on group selection; ... Immune system theory of aging; Inflammation theory of aging; M.
In 1968 it took the form and became known as the neuroendocrine theory of aging. [38] [39] [40] 1956 Denham Harman proposed the free-radical theory of aging and demonstrated that free radical reactions contribute to the degradation of biological systems. [41] The theory is based on the ideas of Rebeca Gerschman and her colleagues put forward in ...
Aging is characterized by a progressive loss of physiological integrity, leading to impaired function and increased vulnerability to death. The hallmarks of aging are the types of biochemical changes that occur in all organisms that experience biological aging and lead to a progressive loss of physiological integrity, impaired function and, eventually, death.
The metabolic stability theory of aging suggests it is the cells ability to maintain stable concentration of ROS which is the primary determinant of lifespan. [37] This theory criticizes the free radical theory because it ignores that ROS are specific signalling molecules which are necessary for maintaining normal cell functions. [37]