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DHEAS Not Biomarker of Aging or CR Not Working in Primates

[posted on behalf of Dean; July 13, 2004 ]

Dean notes a study of the NIA CR primates which found CR doesn't prevent the decline of DHEAS normally associated with aging. So it would appear either DHEAS isn't a very good biomarker of aging (despite its typical age-related decline and apparent positive association with longevity in humans) or else CR isn't slowing aging in these primates...

This study [1] pointed to by another CRONie suggest either DHEAS isn't the
biomarker of aging that some people thought it was (including these same
researchers ...

...or else CR isn't working in the primate studies. Interesting food for
thought...

--Dean

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[1] Ann N Y Acad Sci. 2004 Jun;1019:443-7.

Effect of Caloric Restriction on the 24-Hour Plasma DHEAS and Cortisol
Profiles of Young and Old Male Rhesus Macaques.

Urbanski HF, Downs JL, Garyfallou VT, Mattison JA, Lane MA, Roth GS, Ingram
DK.

Although dietary caloric restriction (CR) can retard aging in laboratory
rats and mice, it is unclear whether CR can exert similar effects in
long-lived species, such as primates. Therefore, we tested the effect of CR
on plasma levels of dehydroepiandrosterone sulfate (DHEAS), a reliable
endocrine marker of aging. The study included six young ( approximately 10
years) and ten old ( approximately 25 years) male rhesus macaques,
approximately half of the animals in each age group having undergone >4
years of 30% CR. Hourly blood samples were collected remotely for 24 hours,
through a vascular catheter, and assayed for DHEAS and cortisol. Both of
these adrenal steroids showed a pronounced diurnal plasma pattern, with
peaks occurring in late morning, but only DHEAS showed an aging-related
decline. More importantly, there was no significant difference in plasma
DHEAS concentrations between the CR animals and age-matched controls. These
data fail to support the hypothesis that CR can attenuate the aging-related
decline in plasma DHEAS concentrations, at least not when initiated after
puberty.

PMID: 15247063