title: Menopause effect on blood Fe and Cu isotope compositions.
abstract: Iron (δ(56) Fe) and copper (δ(65) Cu) stable isotope compositions in blood of adult human include a sex effect, which still awaits a biological explanation. Here, we investigate the effect of menopause by measuring blood δ(56) Fe and δ(65) Cu values of aging men and women. The results show that, while the Fe and Cu isotope compositions of blood of men are steady throughout their lifetime, postmenopausal women exhibit blood δ(65) Cu values similar to men, and δ(56) Fe values intermediate between men and premenopausal women. The residence time of Cu and Fe in the body likely explains why the blood δ(65) Cu values, but not the δ(56) Fe values, of postmenopausal women resemble that of men. We suggest that the Cu and Fe isotopic fractionation between blood and liver resides in the redox reaction occurring during hepatic solicitation of Fe stores. This reaction affects the Cu speciation, which explains why blood Cu isotope composition is impacted by the cessation of menstruations. Considering that Fe and Cu sex differences are recorded in bones, we believe this work has important implications for their use as a proxy of sex or age at menopause in past populations.
authors.affiliation: Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany; Laboratoire de Géologie de Lyon, UMR 5276 CNRS, ENS Lyon, Université Lyon 1, 47 allée d'Italie, 69007, Lyon, France.
authors.forename: Klervia
authors.initials: K
authors.lastname: Jaouen
authors.forename: Vincent
authors.initials: V
authors.lastname: Balter
mesh_terms: D000368:Aged; D000885:Anthropology, Physical; D003300:Copper / Q000097:blood* / Q000737:chemistry; D004912:Erythrocytes; D005260:Female; D022781:Hepatocytes / Q000737:chemistry; D006801:Humans; D007503:Iron Isotopes / Q000097:blood* / Q000737:chemistry; D007554:Isotopes / Q000097:blood / Q000737:chemistry; D008297:Male; D008593:Menopause / Q000097:blood*; D008875:Middle Aged; D018709:Statistics, Nonparametric
chemical_list: D007503:Iron Isotopes; D007554:Isotopes; D003300:Copper
keywords: copper isotopes; iron isotopes; menopause; non-traditional stable isotopes; red blood cells; sex isotope difference