IRON ACCUMULATION IN AGING - MODULATION BY DIETARY RESTRICTION

Male Fischer 344 rats fed ad libitum or dietary restricted (maintained on 60% of ad libitum food intake) were sacrificed at 6, 12 and 24 mon ths of age. Portions of kidney, liver and brain were removed for total iron content analysis and oxidative stress assessment. Total iron con tent was measured directly and lipid peroxidation (LPO) was assayed as an index of oxidative stress. Tissue total iron content was shown to increase significantly with age in animals fed ad libitum (AL). At 24 months, these animals showed comparable iron content increases in the liver and kidney, but were significantly greater than measurements fou nd in brain. This age-related iron accumulation, however, was found to be markedly suppressed by dietry restriction (DR) in all tissues. Sim ilarly, LPO measurements increased in an age-related, tissue-specific fashion. At 24 months of age, measurements of LPO in AL rats brain and liver exceeded measurements in kidney. Again, we found DR to markedly suppress age-related LPO in all tissues. Reported here are our findin gs on the ability of DR to modulate iron status at the tissue level. C onsistent with the proposed anti-oxidative mechanism of DR, these find ings further suggest that the modulation of tissue total iron content is an important component of that mechanism. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.