title: CD44 deficiency inhibits unloading-induced cortical bone loss through downregulation of osteoclast activity.
abstract: The CD44 is cellular surface adhesion molecule that is involved in physiological processes such as hematopoiesis, lymphocyte homing and limb development. It plays an important role in a variety of cellular functions including adhesion, migration, invasion and survival. In bone tissue, CD44 is widely expressed in osteoblasts, osteoclasts and osteocytes. However, the mechanisms underlying its role in bone metabolism remain unclear. We found that CD44 expression was upregulated during osteoclastogenesis. CD44 deficiency in vitro significantly inhibited osteoclast activity and function by regulating the NF-κB/NFATc1-mediated pathway. In vivo, CD44 mRNA levels were significantly upregulated in osteoclasts isolated from the hindlimb of tail-suspended mice. CD44 deficiency can reduce osteoclast activity and counteract cortical bone loss in the hindlimb of unloaded mice. These results suggest that therapeutic inhibition of CD44 may protect from unloading induced bone loss by inhibiting osteoclast activity.
authors.affiliation: State Key Lab of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China.
authors.forename: Yuheng
authors.initials: Y
authors.lastname: Li
authors.affiliation: State Key Lab of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China.
authors.forename: Guohui
authors.initials: G
authors.lastname: Zhong
authors.affiliation: State Key Lab of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China.
authors.forename: Weijia
authors.initials: W
authors.lastname: Sun
authors.affiliation: State Key Lab of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China.|Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Science, Hebei Normal University, Shijiazhuang, China.
authors.forename: Chengyang
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Science, Hebei Normal University, Shijiazhuang, China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Zhang
authors.affiliation: State Key Lab of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China.
authors.forename: Jinping
authors.initials: J
authors.lastname: Song
authors.affiliation: State Key Lab of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China.
authors.forename: Dingsheng
authors.initials: D
authors.lastname: Zhao
authors.affiliation: State Key Lab of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Jin
authors.affiliation: State Key Lab of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Li
authors.affiliation: State Key Lab of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China.
authors.forename: Shukuan
authors.initials: S
authors.lastname: Ling
authors.affiliation: State Key Lab of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China.
authors.forename: Yingxian
authors.initials: Y
authors.lastname: Li
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology; D001862:Bone Resorption / Q000378:metabolism / Q000473:pathology; D001842:Bone and Bones / Q000166:cytology / Q000000981:diagnostic imaging / Q000378:metabolism*; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D015536:Down-Regulation; D018960:Hyaluronan Receptors / Q000235:genetics* / Q000378:metabolism; D016173:Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008856:Microscopy, Fluorescence; D016328:NF-kappa B / Q000378:metabolism; D050778:NFATC Transcription Factors / Q000378:metabolism; D010010:Osteoclasts / Q000166:cytology / Q000378:metabolism*; D010012:Osteogenesis / Q000187:drug effects; D053245:RANK Ligand / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D055114:X-Ray Microtomography
chemical_list: C476399:Cd44 protein, mouse; D018960:Hyaluronan Receptors; D016328:NF-kappa B; D050778:NFATC Transcription Factors; D053245:RANK Ligand; D012333:RNA, Messenger; D016173:Macrophage Colony-Stimulating Factor