Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Age-Dependent Differences in Gene Expression in Response to Calvarial Injury

ABSTRACT: Children less than 2 years of age are capable of healing large calvarial defects, whereas adults have been found to lack this endogenous ability. In this study, we used microarray analysis to compare genomewide expression patterns during active regeneration after injury with calvaria in skeletally immature and mature mice. Parietal bone defects were created in 6-day-old (juvenile) and 60-day-old (adult) mice using a 4-mm trephine bit (n = 20 mice per age group). The calvarial disc was removed, leaving the underlying dura mater intact. Two weeks after injury, the region of regeneration with the underlying dura mater was harvested, and RNA was extracted for microarray analysis. The 25 most differentially upregulated genes in juvenile regenerates compared with adults were listed, as well as selected bone-related genes. In addition, QRT-PCR confirmation of specific genes was performed for validation. Juvenile regenerates expressed significantly greater amounts of BMP-2, -4, -7, as well as FGF-2 and its receptor FGFR-1. Various other growth factors were also noted to be upregulated, including IGF-2 and Ptn. This corresponded with the increased expression of markers for osteogenic differentiation of Sparc and Oc. Markers of osteoclast activity, Acp5, Ctsk, and Mmp2, were noted to be greater in juvenile regenerates compared with adults. The observation of Mmp14 upregulation, however, highlights the importance of balanced osteoclast-mediated bone resorption for ultimate healing. The 2 most differentially regulated genes, transthyretin (Ttr) and prostaglandin D2 synthase (Ptgds), highlight the potential role of retinoic acid signaling and the prostaglandin axis on skeletal regeneration. These findings underscore the multitude of biomolecular mechanisms at play, allowing juvenile calvaria to heal after injury. The identification of various growth factors and cytokines involved also suggests novel therapeutic strategies for tissue-engineering purposes. Set of arrays that are part of repeated experiments Elapsed Time: Calvarial regeneration in 6 day old vs 60 day old mice Biological Replicate

ORGANISM(S): Mus musculus

SUBMITTER: Zhen Wang

PROVIDER: E-GEOD-14424 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Global age-dependent differences in gene expression in response to calvarial injury.

Wan Derrick C DC Kwan Matthew D MD Gupta Deepak M DM Wang Zhen Z Slater Bethany J BJ Panetta Nicholas J NJ Morrell Nathan T NT Longaker Michael T MT

The Journal of craniofacial surgery 20080901 5

Children less than 2 years of age are capable of healing large calvarial defects, whereas adults have been found to lack this endogenous ability. In this study, we used microarray analysis to compare genomewide expression patterns during active regeneration after injury with calvaria in skeletally immature and mature mice. Parietal bone defects were created in 6-day-old (juvenile) and 60-day-old (adult) mice using a 4-mm trephine bit (n = 20 mice per age group). The calvarial disc was removed, l ...[more]

PMID: 18812854

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Dataset Information

Age-Dependent Differences in Gene Expression in Response to Calvarial Injury

Publications

Global age-dependent differences in gene expression in response to calvarial injury.

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