Effect of EglN1 knockdown on smooth muscle expression. Mus musculus

Ischemic preconditioning is the phenomenon whereby brief periods of sublethal ischemia protect against a subsequent, more prolonged, ischemic insult. In remote ischemic preconditioning (RIPC), ischemia to one organ protects other organs at a distance. We developed mouse models to ask if inhibition of EglN1, which senses oxygen and regulates the HIF transcription factor, could suffice to mediate local and remote ischemic preconditioning. We used microarrays to detail the global expression changes induced when the oxygen sensor EglN1 is genetically deleted from skeletal muscle cells. We also used microarrays to assess the transcriptome alterations that occur in mouse hearts with pharmacologic inhibition of EglN1, using the EglN inhibitor FG-4497. Overall design: We generated mice with a tamoxifen-inducible model of EglN1 loss using a floxxed EglN1 locus with skeletal muscle-specific CRE recombinase. WT mice and mice with the floxxed EglN1 locus were exposed to tamoxifen. Mouse skeletal muscle was isolated for RNA extraction and hybridization on Affymetrix microarrays. In a related experiment, mice were treated with the EglN inhibitor FG-4497, and RNA from their heart tissue was analyzed by microarray for transcriptome alterations compared to control hearts.