title: Effects of strontium on collagen content and expression of related genes in rat chondrocytes cultured in vitro.
abstract: Strontium stimulates cartilage matrix formation in vitro. However, the mechanisms governing these effects have not yet been extensively reported. In this study, chondrocytes were isolated from rat articular cartilage by enzymatic digestion and cultured for 24-72 h with 1-5 mM strontium. We investigated the effects of different concentrations of strontium on collagen content, type II collagen, insulin-like growth factor (IGF-1) and matrix metalloproteinase (MMP)-13 expression in rat cultured articular chondrocytes in vitro. The collagen content of the chondrocytes, determined as hydroxyproline, was measured by a colorimetry method. Type II collagen, IGF-1, and MMP-13 mRNA abundance and protein expression levels were determined by real-time polymerase chain reaction (real-time PCR) and western blot, respectively. The results showed that collagen content from the chondrocytes extracellular matrix increased with increasing strontium concentration. Moreover, 3 and 5 mM strontium strongly stimulated protein expression and mRNA levels of type II collagen and IGF-1. Conversely, MMP-13 expression in chondrocytes decreased dose-dependently with increasing strontium concentration. These results should provide insight into the ability of strontium to promote chondrocyte extracellular matrix synthesis. Strontium could promote collagen synthesis and suppress collagen degradation via the repression of MMP-13 expression.
authors.affiliation: College of Animal Science and Veterinary Medicine, Jilin University, Changchun 130062, China.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Wang
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Zhu
authors.forename: Lei
authors.initials: L
authors.lastname: Liu
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Shi
authors.forename: Liheng
authors.initials: L
authors.lastname: Yin
authors.forename: Yuming
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Li
authors.forename: Zhe
authors.initials: Z
authors.lastname: Wang
authors.forename: Guowen
authors.initials: G
authors.lastname: Liu
mesh_terms: D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D002358:Cartilage, Articular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D002478:Cells, Cultured; D019902:Chondrocytes / Q000187:drug effects* / Q000378:metabolism; D003094:Collagen / Q000378:metabolism*; D017931:DNA Primers; D016326:Extracellular Matrix Proteins / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects*; D066298:In Vitro Techniques; D008297:Male; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D060888:Real-Time Polymerase Chain Reaction; D013324:Strontium / Q000494:pharmacology*
chemical_list: D017931:DNA Primers; D016326:Extracellular Matrix Proteins; D012333:RNA, Messenger; D003094:Collagen; D013324:Strontium