Olfactory sensory neuron-specific IGF1R knockout in mice results in increased smell perception, insulin resistance and adiposity

Olfaction is fundamental for survival but there is little known about the connection between smell perception and metabolism. In this study we implemented IGF1R knockout mice in the olfactory sensory neurons, by olfactory marker protetin (OMP) Cre specific recombination, and investigated metabolic parameters, smell perception and transcriptome sequencing. We could demonstrate that IGF1R knockout in the olfactory sensory neurons results in enhanced smell perception, insulin resistance under normal chow diet conditions and increased adiposity in mice fed control diet. Transcriptome analysis of the olfactory epithelium revealed differential expression of markers for mature and immature olfactory sensory neurons, being down-regulated and up- regulated respectively, pointing to differentiation-dependent changes that result in increased olfactory perception. Collectively, this study provides evidence that enhanced smell perception can result in insulin resistance and increased adiposity. mRNA profiles of olfactory sensory neurons (OSN) extracted from homozygous tissue-specific IGF1R knockout (OMPIGF1R) and respective cotnrol mice (OMPflfl) were generated by deep sequencing, in four replicates using Illumina sequencing