Long-term dietary supplementation strawberry , spinach, or vitamin E retards the onset of age-related neuronal signal-transduction and cognitive behavioral deficits.

    Recent research has indicated that increased vulnerability to oxidative stress may be the major factor involved in CNS functional declines in aging and age-related neurodegenerative diseases, and that antioxidants, e.g., Vitamin E, may ameliorate or prevent these declines.

    Present studies examined whether long-term feeding of Fischer 344 rats, beginning when the rats were 6 months of age and continuing for 8 months, with diets supplemented with a fruit or vegetable extract identified as being high in antioxidant activity, could prevent the age-related induction of receptor-mediated signal transduction deficits that might have a behavioral component.

    Thus, the following parameters were examined:

        1) oxotremorine-enhanced striatal dopamine release (OX-K+-ERDA),

        2) cerebellar beta receptor augmentation of GABA responding,

        3) striatal synaptosomal 45Ca2+ clearance,

        4) carbachol-stimulated GTPase activity, and (5) Morris water maze performance.

    The rats were given control diets or those supplemented with strawberry, extracts (SE), 9.5 gm/kg dried aqueous extract (DAE), spinach (SPN 6.4 gm/kg DAE) or Vitamin E (500 IU/kg). Results indicated that SPN-fed rats demonstrated the greatest retardation of age-effects on all parameters except GTPase activity, on which SE had the greatest effect, whereas SE and Vitamin E showed significant but equal protection against these age-induced deficits on the other parameters.

    For example, OX-K+-ERDA enhancement was four times greater in the SPN group than in controls.

    Thus, Phytochemicals present in antioxidant-rich foods such as spinach may be beneficial in retarding functional age-related CNS and cognitive behavioral deficits and, perhaps, may have some benefit in neurodegenerative disease.



REFERENCES
Joseph, J.A.; Shukitt-Hale, B.; Denisova, N.A.; Prior, F.L.; Cao, G.; Martin, A.; Taglialatela, G.; Bickford, P.C. United States Department of Agriculture Human Nutrition Research Center on Aging at Tufts, Boston Massachusetts 02111, USA. J Neurosci 1998 Oct 1;18 (19):8047-55

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