Medzhitov - 'What is a disease?'


Dr Ruslan Medzhitov presented 'What is a disease' at the inaugural meeting of the International Society for Evolution, Medicine and Public Health held March 19-21, 2015.

Interesting perspective on the causes of type 2 diabetes and diseases of aging.

9:13 Robustness, resilience and vulnerability 
15:45 Anna Karenina Principle in Life History Theory - only one way an environment can be perfect and many ways it can be hostile 
16:00 Homeostasis - Maintenance - Defense
17:58 taking out the garbage is not part of homeostasis, it's a function of maintenance 
20:24 Extrinsic and Intrinsic Mortality - investment in maintenance programs is dictated by extrinsic mortality rates 
32:00 systems that have adjustable set points are vulnerable to dysregulation
example: insulin signalling pathway - change in glucose allocation to fetus in pregnancy or to immune system in infection "That built-in property to change the set point of the insulin system also makes it vulnerable to type 2 diabetes and other diseases. ... Not all systems are vulnerable to diseases of homeostatis, only [those] with adjustable homeostatic set points." 
33:32 Category 5 - Diseases caused by lack of maintenance -- all age-related diseases - consequence of antagonistic pleiotropy - maintenance mechanisms are not studied as such (e.g., DNA repair) - diseases that are preventable but not naturally curable, e.g., most cancers, neurodegenerative diseases, type 2 diabetes
39:00 Summary 
42:16 Q&A - Is aging a disease? 
42:59 antagonistic pleiotropy vs. mutation accumulation 
43:47 the categories are not unique [mutually exclusive?] - same disease can arise due to different causalities

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