title: Relationship between plasma ghrelin, insulin, leptin, interleukin 6, adiponectin, testosterone and longevity in the Baltimore Longitudinal Study of Aging.
abstract: OBJECTIVE
  Caloric restriction (CR) is the most robust and reproducible intervention for slowing aging, and maintaining health and vitality in animals. Previous studies found that CR is associated with changes in specific biomarkers in monkeys that were also associated with reduced risk of mortality in healthy men. In this study we examine the association between other potential biomarkers related to CR and extended lifespan in healthy humans.
  
  
  METHODS
  Based on the Baltimore Longitudinal Study of Aging, "long-lived" participants who survived to at least 90 years of age (n=41, cases) were compared with "short-lived" participants who died between 72-76 years of age (n=31, controls) in the nested case control study. Circulating levels of ghrelin, insulin, leptin, interleukin 6, adiponectin and testosterone were measured from samples collected between the ages 58 to 70 years. Baseline differences between groups were examined with t-test or Wilcoxon test, and mixed effects general linear model was used for a logistic model to differentiate the two groups with multiple measurements on some subjects.
  
  
  RESULTS
  At the time of biomarkers evaluation (58-70 yrs), none of the single biomarker levels was significantly different between the two groups. However, after combining information from multiple biomarkers by adding the z-transformed values, the global score differentiated the long- and short-lived participants (p=0.05).
  
  
  CONCLUSIONS
  In their sixties, long-lived and short-lived individuals do not differ in biomarkers that have been associated with CR in animals. However, difference between the groups was only obtained when multiple biomarker dysregulation was considered.
authors: National Institute on Aging, Clinical Research Branch, Longitudinal Studies Section, Baltimore, MD 21225, USA.
authors: Sari
authors: S
authors: Stenholm
authors: E Jeffrey
authors: EJ
authors: Metter
authors: George S
authors: GS
authors: Roth
authors: Donald K
authors: DK
authors: Ingram
authors: Julie A
authors: JA
authors: Mattison
authors: Dennis D
authors: DD
authors: Taub
authors: Luigi
authors: L
authors: Ferrucci
mesh_terms: D052242:Adiponectin / Q000097:blood; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood*; D015142:Baltimore; D015415:Biomarkers / Q000097:blood; D031204:Caloric Restriction; D016022:Case-Control Studies; D054439:Ghrelin / Q000097:blood; D006801:Humans; D007328:Insulin / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D020738:Leptin / Q000097:blood; D008136:Longevity / Q000502:physiology*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D013739:Testosterone / Q000097:blood
chemical_list: C499918:ADIPOQ protein, human; D052242:Adiponectin; D015415:Biomarkers; D054439:Ghrelin; C508600:IL6 protein, human; D007328:Insulin; D015850:Interleukin-6; D020738:Leptin; D013739:Testosterone