what are some biochemical changes

[kitesurfer]

what are some biochemical changes which occur as people age which cause disease

[jubzy]

free radical biology would be agood place to start:
the redox state of cells has its equilibrium altered in favour of more free radical production (O22-, H2O2- SUPEROXIDE, PEROXIDE ETC). this would imply that the antioxidant systems (NADP-NADPH, Vitamins E,C) are less effective (which to some extent is true). free radical damage to a cell would lead to lipid peroxidation, protein degradation (including the chromosomes, and therefore genetic mutations). inevitably there would be damage to the cells, enough to significantly affect metabolism and normal cellular functions. in the end, cell death would occurs in the form of apoptosis and necrosis (not sure about the latter).

seriously, i studied this 2 years ago, so please forgive my ignorance or faults.

i would suggest a book called: free radical biology by Halliwell. it aided my 75% mark achieved in my free radical biochem essay as it provided me with the backbone to do furher research.

hope this helps

[Yanzo]

I would agree with the previous post.

Biochemical changes to proteins, lipids and DNA all occur - there are numerous theories on each - with emphasis mostly based on a genetic level with an accumulation of free radicals damaging genes in DNA, creating dysfunctional enzymes in the Free Radical Theory of Aging and in mitochondria in the Mitochondrial Theory of Ageing.

Other points such as the regeneration of cells (or lack of in motor and brain) could also be considered particularly looking at mutations, the role of telomeres and if you watch those anti-ageing skin commercials, peptide and collagen production!

I think 'senscence' is the key word you are after.