Changes of trace element status during aging: results of the EPIC-Potsdam cohort study

Abstract

Purpose We aimed to evaluate age-dependent changes of six trace elements (TE) [manganese (Mn), iron (Fe), zinc (Zn), copper (Cu), iodine (I), and selenium (Se)] over a 20-year period. Methods TE concentrations were determined using repeated serum samples taken at baseline and after 20 years of follow-up from 219 healthy participants of the EPIC-Potsdam study, using inductively coupled plasma tandem mass spectrometry. For each TE, absolute and relative differences were calculated between the two time points, as well as the proportion of individuals within normal reference ranges. Interdependence between age-related TE differences was investigated using principal component analysis (PCA). Relationships between selected factors (lifestyle, sociodemographic, anthropometric factors, and hypertension) and corresponding TE longitudinal variability were examined using multivariable linear regression models.Results Median age of our study sample was 58.32 years (4.42) at baseline and 40% were females. Median Mn, Zn, Se concentrations and Se to Cu ratio significantly decreased during aging while median Fe, Cu, I concentrations and Cu to Zn ratio significantly increased. A substantial percentage of the participants, at both time points, had Zn concentrations below the reference range. The first PCA-extracted factor reflected the correlated decline in both Mn and Zn over time while the second factor reflected the observed (on average) increase in both Cu and I over time. Overall, none of the investigated factors were strong determinants of TE longitudinal variability, except possibly dietary supplement use, and alcohol use for Fe. Conclusions In conclusion, in this population-based study of healthy elderly, decrease in Mn, Zn, and Se concentrations and increase in Fe, Cu, and I concentrations were observed over 20 years of follow-up. Further research is required to investigate dietary determinants and markers of TE status as well as the relationships between TE profiles and the risk of age-related diseases.

Copper interferes with selenoprotein synthesis and activity

“…However, in vivo the effects were rather small under conditions of a mild modulation of the Cu status in the adequate to suboptimal concentration range in healthy, young mice. The average human serum concentration of Cu ranges from 15 to 31.5 μM [ [75] , [76] , [77] ], and thus concentrations used in cell culture experiments are adequate to supplemented. But under pathophysiological conditions up to 200 μM Cu were reported in serum [ 78 ].…”

“…Also under physiological conditions, serum Cu concentrations can be increased as recently described when comparing a subcohort of the EPIC Potsdam cohort which has been reinvited after 20 years. Advanced age was associated with increased Cu concentrations and decreased Se concentrations [ 76 ]. This indicates that an age-related decline in selenoprotein expression most probably is a result of a combination of lower Se concentrations and higher Cu concentration.…”

Crosstalk of Nrf2 with the Trace Elements Selenium, Iron, Zinc, and Copper

“…A reduction of Nrf2 levels and responsiveness is a relevant health condition that physiologically takes place during aging [38]. Thus, the question arises whether age-specific changes in TE profiles [39] might be related to Nrf2. Recently, it has been examined that Nrf2 activity levels strongly differ in the liver of male and female mice [40].…”

Dietary Selenium Supplementation Ameliorates Female Reproductive Efficiency in Aging Mice

“…Both Se deficiency and excess levels have been shown to influence the redox status and lead to severe adverse health consequences in animals and humans [10,21]. Interestingly, recently it has been demonstrated that plasma Se concentrations tend to decline in certain healthy human populations comprised of older subjects [22]. It was also reported that Se bioavailability was impacted by aging [13,23].…”