title: Abnormal response of the proliferation and differentiation of growth plate chondrocytes to melatonin in adolescent idiopathic scoliosis.
abstract: Abnormalities in the melatonin signaling pathway and the involvement of melatonin receptor MT2 have been reported in patients with adolescent idiopathic scoliosis (AIS). Whether these abnormalities were involved in the systemic abnormal skeletal growth in AIS during the peripubertal period remain unknown. In this cross-sectional case-control study, growth plate chondrocytes (GPCs) were cultured from twenty AIS and ten normal control subjects. Although the MT2 receptor was identified in GPCs from both AIS and controls, its mRNA expression was significantly lower in AIS patients than the controls. GPCs were cultured in the presence of either the vehicle or various concentrations of melatonin, with or without the selective MT2 melatonin receptor antagonist 4-P-PDOT (10 µM). Then the cell viability and the mRNA expression of collagen type X (COLX) and alkaline phosphatase (ALP) were assessed by MTT and qPCR, respectively. In the control GPCs, melatonin at the concentrations of 1, 100 nM and 10 µM significantly reduced the population of viable cells, and the mRNA level of COLX and ALP compared to the vehicle. Similar changes were not observed in the presence of 4-P-PDOT. Further, neither proliferation nor differentiation of GPCs from AIS patients was affected by the melatonin treatment. These findings support the presence of a functional abnormality of the melatonin signaling pathway in AIS GPCs, which might be associated with the abnormal endochondral ossification in AIS patients.
authors.affiliation: Department of Spine Surgery, Drum Tower Hospital, Nanjing University Medical School, Nanjing 210008, China. drwilliamwang@163.com.
authors.forename: William Wei-Jun
authors.initials: WW
authors.lastname: Wang
authors.affiliation: Department of Obstetrics and Gynaecology, Faculty of Medicine, the Chinese University of Hong Kong, Hong Kong, China. geneman@cuhk.edu.hk.
authors.forename: Gene Chi-Wai
authors.initials: GC
authors.lastname: Man
authors.affiliation: School of Biomedical Sciences, the Chinese University of Hong Kong, Hong Kong, China. jack1993@yahoo.com.
authors.forename: Jack Ho
authors.initials: JH
authors.lastname: Wong
authors.affiliation: School of Biomedical Sciences, the Chinese University of Hong Kong, Hong Kong, China. tzibunng@cuhk.edu.hk.
authors.forename: Tzi-Bun
authors.initials: TB
authors.lastname: Ng
authors.affiliation: Lee Hysan Clinical Research Laboratory, the Chinese University of Hong Kong, Hong Kong, China. simonlee@cuhk.edu.hk.
authors.forename: Kwong-Man
authors.initials: KM
authors.lastname: Lee
authors.affiliation: Department of Orthopaedics and Traumatology, the Chinese University of Hong Kong, Hong Kong, China. bobng@ort.cuhk.edu.hk.
authors.forename: Bobby Kin-Wah
authors.initials: BK
authors.lastname: Ng
authors.affiliation: Department of Orthopaedics and Traumatology, the Chinese University of Hong Kong, Hong Kong, China. benson914@gmail.com.
authors.forename: Hiu-Yan
authors.initials: HY
authors.lastname: Yeung
authors.affiliation: Department of Spine Surgery, Drum Tower Hospital, Nanjing University Medical School, Nanjing 210008, China. scoliosis2002@sina.com.
authors.forename: Yong
authors.initials: Y
authors.lastname: Qiu
authors.affiliation: Department of Orthopaedics and Traumatology, the Chinese University of Hong Kong, Hong Kong, China. jackcheng@cuhk.edu.hk.
authors.forename: Jack Chun-Yiu
authors.initials: JC
authors.lastname: Cheng
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D019902:Chondrocytes / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D005260:Female; D019204:GTP-Binding Proteins / Q000378:metabolism; D006132:Growth Plate / Q000473:pathology*; D006801:Humans; D008297:Male; D008550:Melatonin / Q000494:pharmacology*; D019637:Orthopedic Procedures; D061251:Primary Cell Culture; D012333:RNA, Messenger / Q000096:biosynthesis; D044123:Receptor, Melatonin, MT2 / Q000096:biosynthesis / Q000172:deficiency / Q000187:drug effects / Q000235:genetics; D012600:Scoliosis / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D015398:Signal Transduction; D013123:Spinal Fusion
chemical_list: D012333:RNA, Messenger; D044123:Receptor, Melatonin, MT2; D019204:GTP-Binding Proteins; D008550:Melatonin