title: IL-1RI participates in normal growth plate development and bone modeling.
abstract: The proinflammatory cytokine interleukin-1 (IL-1) signals through IL-1 receptor type I (IL-1RI) and induces osteoclastogenesis and bone resorption mainly during pathological conditions. Little is known about the effect of excess or absence of IL-1 signaling on the physiological development of the growth plate and bone. In this study, we examine growth plate morphology, bone structure, and mechanical properties as well as osteoclast number in IL-1RI knockout mice to evaluate the role of IL-1RI in the normal development of the growth plate and bone. We show for the first time that IL-1RI knockout mice have narrower growth plates due to a smaller hypertrophic zone, suggesting a role for this cytokine in hypertrophic differentiation, together with higher proteoglycan content. The bones of theses mice exhibit higher trabecular and cortical mass, increased mineral density, and superior mechanical properties. In addition, IL-1RI knockout mice have significantly reduced osteoclast numbers in the chondro-osseous junction, trabecular bone, and cortical bone. These results suggest that IL-1RI is involved in normal growth plate development and ECM homeostasis and that it is significant in the physiological process of bone modeling.
authors.affiliation: Institute of Biochemistry and Nutrition, The Robert H. Smith Faculty of Agriculture, Food, and Environment, The Hebrew University, Rehovot, Israel.
authors.forename: Stav
authors.initials: S
authors.lastname: Simsa-Maziel
authors.forename: Janna
authors.initials: J
authors.lastname: Zaretsky
authors.forename: Adi
authors.initials: A
authors.lastname: Reich
authors.forename: Yoav
authors.initials: Y
authors.lastname: Koren
authors.forename: Ron
authors.initials: R
authors.lastname: Shahar
authors.forename: Efrat
authors.initials: E
authors.lastname: Monsonego-Ornan
mesh_terms: D000818:Animals; D016723:Bone Remodeling / Q000502:physiology*; D006132:Growth Plate / Q000000981:diagnostic imaging / Q000254:growth & development* / Q000502:physiology*; D006706:Homeostasis / Q000502:physiology; D053583:Interleukin-1beta / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D010010:Osteoclasts / Q000166:cytology / Q000502:physiology; D011509:Proteoglycans / Q000378:metabolism; D011859:Radiography; D053573:Receptors, Interleukin-1 Type I / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*; D013977:Tibia / Q000000981:diagnostic imaging / Q000254:growth & development / Q000502:physiology
chemical_list: C583355:IL1R1 protein, mouse; D053583:Interleukin-1beta; D011509:Proteoglycans; D053573:Receptors, Interleukin-1 Type I
keywords: bone mechanics; bone structure; interleukin-1; interleukin-1 receptor type I; osteoclasts