1 Department of Experimental, Diagnostic and Specialty Medicine, Alma Mater Studiorum, University of Bologna, Bologna; IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy; Department of Applied Mathematics, Institute of Information Technology, Mathematics and Mechanics (ITMM), Lobachevsky State University of Nizhny Novgorod-National Research University (UNN), Nizhny Novgorod, Russia. Electronic address: claudio.franceschi@unibo.it.
2 Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, NIH Biomedical Research Center, 251 Bayview Blvd, Baltimore, MD 21224, USA. Electronic address: broshr@grc.nia.nih.gov.
3 Aging Research Center, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet and Stockholm University, Stockholm, Sweden; Stockholm Gerontology Research Centre, Stockholm, Sweden. Electronic address: laura.fratiglioni@ki.se.
4 Department of Experimental, Diagnostic and Specialty Medicine, Alma Mater Studiorum, University of Bologna, Bologna; IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy; C.I.G. Interdepartmental Centre "L. Galvani", Alma Mater Studiorum, University of Bologna, Bologna, Italy. Electronic address: stefano.salvioli@unibo.it.
5 Department of Experimental, Diagnostic and Specialty Medicine, Alma Mater Studiorum, University of Bologna, Bologna; IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy; C.I.G. Interdepartmental Centre "L. Galvani", Alma Mater Studiorum, University of Bologna, Bologna, Italy. Electronic address: aurelia.santoro@unibo.it.