title: Transgenic expression of human IGF1 in intervertebral degenerative discs.
abstract: This study investigated the role of human insulin-like growth factor-1 (hIGF-1; encoded by the hIGF1 gene) on intervertebral disc degeneration. A total of 24 male New Zealand rabbits of an intervertebral disc degeneration (IVDD) model were randomly divided into three groups where the following were injected into the lumbar 4 - 5 and 5 - 6 discs: second generation adenovirus containing cytomegalovirus hIGF1 (Ad/CMV-hIGF1); 100 μg/l hIGF-1 protein; or phosphate-buffered saline. At 1, 2, 4 and 8 weeks post-injection, intervertebral disc samples were harvested. Human IGF-1 protein was detected using Western blot analysis, and aggrecan and collagen type II gene fragments were quantified using reverse transcription-polymerase chain reaction. At week 1 post-injection, hIGF-1 protein levels were similar in the Ad/CMV-hIGF1 and hIGF-1 groups. By week 2 the level had decreased substantially in the hIGF-1 group. At week 4 it was still present in the Ad/CMV-hIGF1 group and, by week 8, no protein was detected in any of the three groups. Aggrecan and collagen type II mRNA levels increased in the Ad/CMV-hIGF1 group 1 - 4 weeks post-injection, but declined by week 8, while both decreased steadily over 8 weeks in the other two groups. In conclusion, hIGF1 gene expression lasted for 4 weeks and stimulated the synthesis of aggrecan and collagen type II in the Ad/CMV-hIGF1 group.
authors.affiliation: Spine Microsurgery Centre, First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Z Q
authors.initials: ZQ
authors.lastname: Huang
authors.forename: Z M
authors.initials: ZM
authors.lastname: Zheng
authors.forename: J
authors.initials: J
authors.lastname: Yan
mesh_terms: D053674:Aggrecans / Q000235:genetics / Q000378:metabolism; D000818:Animals; D030801:Animals, Genetically Modified; D015153:Blotting, Western; D024043:Collagen Type II / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000235:genetics*; D007403:Intervertebral Disc / Q000378:metabolism / Q000473:pathology; D055959:Intervertebral Disc Degeneration / Q000235:genetics* / Q000473:pathology; D008297:Male; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011817:Rabbits
chemical_list: D053674:Aggrecans; D024043:Collagen Type II; D012333:RNA, Messenger; D007334:Insulin-Like Growth Factor I