| Summary This  second of three discussions about ageing biology and diseases continues at the  level of the organism, examining the relationship among body composition, late  life and diseases. One view of significant age-related mass loss in humans  suggests that anabolic failure is associated with various precipitating factors  that may share anorexia in common. Lean mass decline with even partial anorexia  should alert clinicians to monitor patients for emergence of otherwise  subclinical disease. Weight or mass loss and clinical disease also may be  independent, thus creating an interwoven and complex view. Recent data from the  Portuguese water dog genetics model suggest that heritable factors play a role  in end of life body metrics and some histological changes, and that some metric  and histological changes are themselves inter-related. While widespread  inflammation and hyperplasia were less frequent than expected, there exists  nonetheless a disease relationship to the growth hormone (GH)-insulin-like  growth factor (IGF-1)-insulin axis that requires further exploration. Oxidative  metabolism and apoptosis are reviewed briefly as examples at the cellular level  that may be reflected in gross ageing phenotypes, further underscoring the  complex nature of many late-life diseases.
 KeywordsAgeing  diseases, Anabolic failure, Apoptosis, Body composition, Free radical theory,  Genetics, Hormesis, IGF-1, Insulin-like growth factor, Portuguese water dog.
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