Metals in plasma of nonagenarians and centenarians living in a key area of longevity

The concentration of calcium (Ca), cobalt (Co), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn) and selenium (Se) in plasma of 76 nonagenarians (mean age, 89.0 ± 6.3 years), 64 centenarians (mean age, 101 ± 1 years) and 24 middle-aged subjects as controls (mean age 61.2 ± 1.1 years), was determined by sector field inductively coupled plasma mass spectrometry. All the subjects lived in Sardinia, an Italian island, that has the higher prevalence of centenarians than in other European countries. A comparison among the three classes of age showed a significant depletion of Ca, Co, Fe, Mn and Se (all p < 0.001) in nonagenarians and centenarians with respect to controls. In particular, the geometric mean (GM) values of Ca, Co, Fe, Mn and Se were: 94.1 μg/ml, 0.46 ng/ml, 1314 ng/ml, 2.47 ng/ml and 111 ng/ml in controls; 87.6 μg/ml, 0.22 ng/ml, 815 ng/ml, 1.07 ng/ml and 88.9 ng/ml in nonagenarians; 87.0 μg/ml, 0.29 ng/ml, 713 ng/ml, 1.27 ng/ml and 81.9 ng/ml in centenarians. The highest inverse relationship with age was observed for Fe (p < 0.001; ρ = − 0.352) and Se (p < 0.001; ρ = − 0.417). This trend was also observed when data were sorted by gender. On the other hand, Cu and Mg levels in plasma remained substantially unchanged during aging. As regards Cu, it was significantly higher in females than in males in controls (GM, 1294 ng/ml vs. 1077 ng/ml; p = 0.012), in nonagenarians (GM, 1216 ng/ml vs. 1081 ng/ml; p = 0.011) as well as in centenarians (GM, 1226 ng/ml vs. 1152 ng/ml; p = 0.045) and in hypertensive subjects with respect to healthy people (GM, 1215 ng/ml vs. 1129 ng/ml; p = 0.021). These data can be used to enhance knowledge and support the research on: i) metals involved in aging in areas with high rates of human longevity; ii) variables (gender, lifestyle habits and health status) as critical determinants in aging; and iii) mineral intake and supplementation at older age affecting the healthy aging.