title: Zinc, immune plasticity, aging, and successful aging: role of metallothionein.
abstract: The capacity of the remodeling immune responses during stress (immune plasticity) is fundamental to reach successful aging. We herein report two pivotal models to demonstrate the relevance of the immune plasticity in aging and successful aging. One model is represented by the circadian rhythms of immune responses; the other one is the immune responses during partial hepatectomy/liver regeneration (pHx). The latter is suggestive because it mimics the immunosenescence and chronic inflammation 48 hours after partial hepatectomy in the young through the continuous production of IL-6, which is the main cause of immune plasticity lack in aging. The constant production of IL-6 leads to abnormal increments of zinc-bound metallothionein (MT), which is, in turn, unable in zinc release in aging. As a consequence, low zinc ion bioavailability appears for thymic and extrathymic immune efficiency, in particular, of liver NKT cells bearing TCR gd. The remodeling during the circadian cycle and during pHx of zinc-bound MT confers the immune plasticity of liver NKT gamma delta cells and NK cells in young and very old age, not in old age. Therefore, zinc-bound MT homeostasis is crucial in conferring liver immune plasticity with subsequent successful aging.
authors.affiliation: Immunology Center, Section Nutrition, Immunity and Ageing, Research Department I.N.R.C.A., Via Birarelli 8, 60121, Ancona, Italy. e.mocchegiani@inrca.it
authors.forename: Eugenio
authors.initials: E
authors.lastname: Mocchegiani
authors.forename: Robertina
authors.initials: R
authors.lastname: Giacconi
authors.forename: Elisa
authors.initials: E
authors.lastname: Muti
authors.forename: Cinzia
authors.initials: C
authors.lastname: Rogo
authors.forename: Massimo
authors.initials: M
authors.lastname: Bracci
authors.forename: Mario
authors.initials: M
authors.lastname: Muzzioli
authors.forename: Catia
authors.initials: C
authors.lastname: Cipriano
authors.forename: Marco
authors.initials: M
authors.lastname: Malavolta
mesh_terms: D000375:Aging; D000818:Animals; D002940:Circadian Rhythm; D007249:Inflammation; D015850:Interleukin-6 / Q000378:metabolism; D007694:Killer Cells, Natural / Q000378:metabolism; D008099:Liver / Q000473:pathology / Q000502:physiology; D008668:Metallothionein / Q000378:metabolism / Q000502:physiology*; D051379:Mice; D008954:Models, Biological; D012038:Regeneration; D013997:Time Factors; D015032:Zinc / Q000378:metabolism*
chemical_list: D015850:Interleukin-6; D008668:Metallothionein; D015032:Zinc