CD24 regulates gene expression in pre-adipocytes in response to IBMX and Dexamethasone stimulation

Previous in vitro studies in our lab have shown that CD24, a cell surface receptor, actively regulates lipid accumulation in adipocytes. But how CD24 regulates this process remains unknown. In order to answer this question, we initially tested to determine if CD24 regulates lipid accumulation by regulating glucose uptake in adipocytes in vitro. We observed that instead, CD24 caused the dysregulation of the expression of 134 genes as determined by DNA microarray analysis. We then validated the expression of select four genes, when CD24 is knocked down during the different stages of adipogenesis in 3T3-L1 pre-adipocytes in vitro. To further confirm the role of these genes, we then determined the expression patterns of these four genes in primary cells undergoing adipogenesis that were isolated from the epididymal and inguinal white adipose tissue depots of CD24 knockout mice. Surprisingly, we found that these genes were dysregulated in the inguinal but not the epididymal depot in vitro. Overall, the data presented here suggests that CD24 is necessary for select gene expression, but not glucose uptake, during adipogenesis in vitro. Comparison of 3T3-L1 confluent pre-adipocytes treated with IBMX and Dexamethasone (Dex) for 6 hours if CD24 is knocked-down with siRNA or not. IBMX/Dex samples were compared to vehicle-treated controls.