title: Circadian distribution of iron and ferritin in serum of healthy and type 2 diabetic males.
abstract: OBJECTIVE
  We examined the circulating levels of iron and ferritin in serum of seven healthy and three insulin non-dependent diabetic (Type 2) males in order to compare their circadian characteristics.
  
  
  METHODS
  Blood samples were collected every 3h over a 24h period and were analyzed for serum iron and ferritin.
  
  
  RESULTS
  The mean Fe level was significantly higher in healthy than in diabetic subjects: 80.0 +/- 3.3 vs. 63.0 +/- 3.7 microg/dL. The ferritin level was significantly lower in healthy than in diabetic men: 79.8 +/- 4.7 vs. 186.3 +/- 110.5 microg/L. A significant (p < 0.001) time-effect was found by ANOVA and circadian rhythm was detected at p < 0.001 in all data sets when a 24h cosine was fitted to the normalized data. Acrophases were located in mid to late morning for Fe (11:30, vs. 09:22h) and for ferritin (11:10 vs. 11:46h).
  
  
  CONCLUSIONS
  We concluded that there is significant circadian variation in both serum Fe and ferritin, with predictable peaks in the mid to late morning.
authors: Cardiology Laboratory, Edward Hines, Jr Veterans Medical Center, Hines, IL 60141, USA.
authors: J L H C
authors: JL
authors: Third
authors: M D
authors: MD
authors: Ryan
authors: R B
authors: RB
authors: Sothern
authors: S
authors: S
authors: Dawson
authors: J B
authors: JB
authors: McCormick
authors: H S
authors: HS
authors: Hoffman
authors: A
authors: A
authors: Gathing
authors: R A
authors: RA
authors: Jankowski
authors: K S
authors: KS
authors: Kania
authors: E L
authors: EL
authors: Kanabrocki