Life-long dietary restriction attenuates age-related increases in hippocampal glial fibrillary acidic protein mRNA.

The expression of astrocyte-specific glial fibrillary acidic protein increases after experimental lesions and is elevated throughout the brain in aged rodents and primates. Clusterin (ApoJ) expression increases in astrocytes and microglia after lesions, but changes during aging have not been reported. Dietary restriction (DR) delays the onset and progression of many age-related physiological deficits in rodents. This study showed that the age-related increase in glial fibrillary acidic protein mRNA in the hippocampus was attenuated in 24-month-old male Fischer 344 rats subjected to a 50% DR beginning at 6 weeks of age. ApoJ mRNA expression in astrocytes was unchanged by DR. These results demonstrate that DR can delay neurodegeneration in aged rats as assessed by a marker of reactive astrogliosis.