title: Ageing and the brain.
abstract: In this review, the evidence for changes in the human brain with ageing at both the macroscopic and microscopic levels is summarized. Loss of neurons is now recognized to be more modest than initial studies suggested and only affects some neuron populations. Accompanying loss of neurons is some reduction in the size of remaining neurons. This reflects a reduced size of dendritic and axonal arborizations. Some of the likely causes of these changes, including free radical damage resulting from a high rate of oxidative metabolism in neurons, glycation and dysregulation of intracellular calcium homeostasis, are discussed. The roles of genes and environmental factors in causing and responding to ageing changes are explored.
authors.affiliation: Department of Clinical Neurology, University of Oxford, and Department of Neuropathology, Oxford Radcliffe NHS Trust, Oxford, UK.
authors.forename: M M
authors.initials: MM
authors.lastname: Esiri
mesh_terms: D000375:Aging / Q000235:genetics / Q000473:pathology / Q000502:physiology*; D001057:Apolipoproteins E / Q000235:genetics; D001921:Brain / Q000033:anatomy & histology* / Q000473:pathology / Q000502:physiology; D002118:Calcium / Q000378:metabolism; D031204:Caloric Restriction; D004734:Energy Metabolism / Q000502:physiology; D004777:Environment; D017127:Glycation End Products, Advanced / Q000378:metabolism; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology; D000072002:Prion Proteins; D011328:Prions / Q000235:genetics
chemical_list: D001057:Apolipoproteins E; D017127:Glycation End Products, Advanced; C512656:PRNP protein, human; D000072002:Prion Proteins; D011328:Prions; D002118:Calcium