title: Effects of long time exposure to simulated micro- and hypergravity on skeletal architecture.
abstract: This manuscript reports the structural alterations occurring in mice skeleton as a consequence of the longest-term exposition (90 days) to simulated microgravity (hindlimb unloading) and hypergravity (2g) ever tested. Bone microstructural features were investigated by means of standard Cone Beam X-ray micro-CT, Synchrotron Radiation micro-CT and histology. Morphometric analysis confirmed deleterious bone architectural changes in lack of mechanical loading with a decrease of bone volume and density, while bone structure alterations caused by hypergravity were less evident. In the femurs from hypergravity-exposed mice, the head/neck cortical thickness increment was the main finding. In addition, in these mice the rate of larger trabeculae (60-75 μm) was significantly increased. Interestingly, the metaphyseal plate presented a significant adaptation to gravity changes. Mineralization of cartilage and bone deposition was increased in the 2g mice, whereas an enlargement of the growth plate cartilage was observed in the hindlimb unloaded group. Indeed, the presented data confirm and reinforce the detrimental effects on bone observed in real space microgravity and reveal region-specific effects on long bones. Finally these data could represent the starting point for further long-term experimentations that can deeply investigate the bone adaptation mechanisms to different mechanical force environments.
authors.affiliation: Dipartimento di Medicina Sperimentale, Universita' di Genova & IRCCS AOU San Martino-IST, Istituto Nazionale per la Ricerca sul Cancro, Genova, Italy.
authors.forename: Barbara
authors.initials: B
authors.lastname: Canciani
authors.affiliation: Dipartimento di Medicina Sperimentale, Universita' di Genova & IRCCS AOU San Martino-IST, Istituto Nazionale per la Ricerca sul Cancro, Genova, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Ruggiu
authors.affiliation: Dipartimento di Scienze Cliniche Specialistiche e Odontostomatologiche, Sezione di Biochimica, Biologia e Fisica, Università Politecnica delle Marche, Ancona, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Giuliani
authors.affiliation: Istituto di Fisiologia Clinica, CNR, Pisa, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Panetta
authors.affiliation: Dipartimento di Scienze Cliniche Specialistiche e Odontostomatologiche, Sezione di Biochimica, Biologia e Fisica, Università Politecnica delle Marche, Ancona, Italy.
authors.forename: Katia
authors.initials: K
authors.lastname: Marozzi
authors.affiliation: Istituto di Fisiologia Clinica, CNR, Pisa, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Tripodi
authors.affiliation: Istituto di Fisiologia Clinica, CNR, Pisa, Italy.
authors.forename: Piero A
authors.initials: PA
authors.lastname: Salvadori
authors.affiliation: Animal Facility, IRCCS AOU San Martino-IST Istituto Nazionale per la Ricerca sul Cancro, Genova, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Cilli
authors.affiliation: Graduate School of Health and Sports Science, Doshisha University, Kyoto, Japan.
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Ohira
authors.affiliation: Dipartimento di Medicina Sperimentale, Universita' di Genova & IRCCS AOU San Martino-IST, Istituto Nazionale per la Ricerca sul Cancro, Genova, Italy.
authors.forename: Ranieri
authors.initials: R
authors.lastname: Cancedda
authors.affiliation: Dipartimento di Medicina Sperimentale, Universita' di Genova & IRCCS AOU San Martino-IST, Istituto Nazionale per la Ricerca sul Cancro, Genova, Italy. Electronic address: sara.tavella@unige.it.
authors.forename: Sara
authors.initials: S
authors.lastname: Tavella
mesh_terms: D000818:Animals; D005269:Femur / Q000166:cytology / Q000000981:diagnostic imaging / Q000502:physiology; D006614:Hindlimb / Q000502:physiology; D018471:Hypergravity / Q000009:adverse effects*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D013997:Time Factors; D016474:Weight-Bearing; D018474:Weightlessness Simulation / Q000009:adverse effects*; D055114:X-Ray Microtomography
keywords: Bone microarchitecture; Hypergravity; Mice; Microgravity