Plasma fibronectin in French centenarians.
Labat-Robert1, Marques, N'Doye
1Laboratoire d'Ophtalmologie, Escalier B3, 6ème étage, Hôtel-Dieu, 1 place du parvis Notre-Dame, 75181 Cedex 04, Paris, France
Archives of Gerontology and Geriatrics
|November 25, 2000
Summary
Healthy centenarians exhibit lower plasma fibronectin levels and reduced degradation compared to younger, ill individuals, suggesting better physiological function maintenance with aging.
Area of Science:
- Gerontology
- Biochemistry
- Molecular Biology
Background:
- Plasma fibronectin increases with age, with greater individual variability.
- Fibronectin degradation products can have harmful effects, influencing cellular processes.
- Age-related changes in fibronectin may impact physiological functions.
Purpose of the Study:
- To compare plasma fibronectin levels and degradation in healthy centenarians versus a younger, pathological geriatric population.
- To investigate the role of fibronectin in aging and healthspan.
Main Methods:
- Plasma fibronectin quantification using a sensitive Elisa assay.
- Characterization of fibronectin fragments via immunoblot.
- Comparison of three cohorts: centenarians, geriatric patients, and healthy middle-aged adults (EVA study).
Main Results:
- Centenarians showed lower average plasma fibronectin levels than the geriatric group.
- Fibronectin fragments were detected in geriatric patients but not in centenarians.
- Centenarian plasma fibronectin appeared more resistant to proteolytic degradation.
Conclusions:
- Healthy centenarians maintain moderate plasma fibronectin levels with less degradation.
- Epigenetic factors influencing fibronectin synthesis and degradation may be crucial for healthy aging.
- Protective mechanisms against fibronectin degradation may contribute to preserved physiological functions in centenarians.
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