The effects of different doses of IGF-1 on cartilage and subchondral bone during the repair of full-thickness articular cartilage defects in rabbits.
To investigate the effects of different doses of insulin-like growth factor 1 (IGF-1) on the cartilage layer and subchondral bone (SB) during repair of full-thickness articular cartilage (AC) defects.



IGF-1-loaded collagen membrane was implanted into full-thickness AC defects in rabbits. The effects of two different doses of IGF-1 on cartilage layer and SB adjacent to the defect, the cartilage structure, formation and integration, and the new SB formation were evaluated at the 1st, 4th and 8th week postoperation. Meanwhile, after 1 week treatment, the relative mRNA expressions in tissues adjacent to the defect, including cartilage and SB were determined by quantitative real-time RT-PCR (qRT-PCR), respectively.



Different doses of IGF-1 induced different gene expression profiles in tissues adjacent to the defect and resulted in different repair outcomes. Particularly, at high dose IGF-1 aided cell survival, regulated the gene expressions in cartilage layer adjacent defect and altered ECM composition more effectively, improved the formation and integrity of neo-cartilage. While, at low dose IGF-1 regulated the gene expressions in SB more efficaciously and subsequently promoted the SB remodeling and reconstruction.



Different doses of IGF-1 induced different responses of cartilage or SB during the repair of full-thickness AC defects. Particularly, high dose of IGF-1 was more beneficial to the neo-cartilage formation and integration, while low dose of it was more effective for the SB formation.
Institute of Biomedical Engineering, Chinese Academy of Medical Sciences, Peking Union Medical College, The Key Laboratory of Biomedical Material of Tianjin, Tianjin 300192, PR China. Electronic address: zhangzhe523575127@163.com.
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Zhang
Institute of Biomedical Engineering, Chinese Academy of Medical Sciences, Peking Union Medical College, The Key Laboratory of Biomedical Material of Tianjin, Tianjin 300192, PR China. Electronic address: lilin29pumc@163.com.
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Li
Institute of Biomedical Engineering, Chinese Academy of Medical Sciences, Peking Union Medical College, The Key Laboratory of Biomedical Material of Tianjin, Tianjin 300192, PR China. Electronic address: Yang_eve@163.com.
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Yang
Institute of Biomedical Engineering, Chinese Academy of Medical Sciences, Peking Union Medical College, The Key Laboratory of Biomedical Material of Tianjin, Tianjin 300192, PR China. Electronic address: pumc_yitingcao@163.com.
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Cao
School of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin 300384, PR China. Electronic address: yanpingshi@126.com.
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Shi
Institute of Biomedical Engineering, Chinese Academy of Medical Sciences, Peking Union Medical College, The Key Laboratory of Biomedical Material of Tianjin, Tianjin 300192, PR China. Electronic address: lixuemin-7205@vip.sina.com.
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Li
Institute of Biomedical Engineering, Chinese Academy of Medical Sciences, Peking Union Medical College, The Key Laboratory of Biomedical Material of Tianjin, Tianjin 300192, PR China. Electronic address: zhangqiq@126.com.
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Zhang
D000818:Animals; D001842:Bone and Bones / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D002358:Cartilage, Articular / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D004305:Dose-Response Relationship, Drug; D007334:Insulin-Like Growth Factor I / Q000008:administration & dosage / Q000494:pharmacology*; D011817:Rabbits; D060888:Real-Time Polymerase Chain Reaction
D007334:Insulin-Like Growth Factor I
Articular cartilage; Full-thickness defect; Insulin-like growth factor 1 (IGF-1); Repair; Subchondral bone