• Xizhe Liu, Gentaro Kumagai, Kanichiro Wada, Toshihiro Tanaka, Toru Asari, Kazuki Oishi, Taku Fujita, Hiroki Mizukami, FurukawaKen-IchiKIDepartment of Pharmacology, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan., and Yasuyuki Ishibashi.
• Department of Orthopedic Surgery, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan.
• Spine. 2017 Dec 1; 42 (23): E1342-E1349.

Study DesignBasic experiments in a mouse model of ossification of the posterior longitudinal ligament (OPLL).ObjectiveTo assess the osteogenic potential of mesenchymal stem cells (MSCs) obtained from muscle and adipose tissue in Tiptoe-walking (ttw) mice, in which cervical OPLL compresses the spinal cord and causes motor and sensory dysfunction.Summary Of Background DataIn humans, MSCs have been implicated in the pathogenesis of cervical OPLL. Cervical OPLL in ttw mice causes chronic compression of the spinal cord. Few studies have compared the MSC osteogenic potential with behavioral changes in an OPLL animal model.MethodsWe compared the osteogenic potential and behavioral characteristics of MSCs from ttw mice (4 to 20 weeks old) with those from control wild-type mice (without hyperostosis). Ligament ossification was monitored by micro-computed tomography and pathology; tissues were double stained with fluorescent antibodies against markers for MSCs (CD45 and CD105), at 8 weeks. The Basso Mouse Scale was used to assess motor function, and heat and mechanical tests to assess sensory function. The osteogenic potential of adipose and muscle MSCs was assessed by Alizarin Red S absorbance, staining for osteogenic mineralization, and real-time quantitative polymerase chain reaction for osteogenesis-related genes.ResultsSpinal-ligament ossification began in ttw mice at 8 weeks of age, and the ossified area increased with age. Immunofluorescence staining identified MSCs in the ossification area. The ttw mice became hyposensitive at 8 weeks of age, and Basso Mouse Scale scores showed motor-function deficits starting at 12 weeks of age. Alizarin Red S staining for mineralization showed a higher osteogenic potential in the adipose- and muscle-derived MSCs from ttw mice than from wild-type mice at 4, 8, and 20 weeks of age. Real-time quantitative polymerase chain reaction showed that ttw MSCs strongly expressed osteogenesis-related genes.ConclusionMSCs derived from muscle and adipose tissue in ttw mice had a high osteogenic potential.Level Of EvidenceN/A.

20 keywords...

hide…