Prolonged exposure to cold temperature has shown to induce beiging of white adipose tissue in vivo. However, an in vitro model to study the mechanisms underlying the transdifferentiation ability of white to beige adipocytes is lacking. To develop such a model, 3T3-L1 cells, the most commonly used murine adipocyte cell line, were induced to differentiate using insulin, T3, IMBX, and dexamethasone. Mature adipocytes were then treated with the beta-agonist isoproterenol (10 or 100 µM) for up to 48 hours. Isoproterenol increased the transcription of UCP1 and beige markers CD137, CITED1, and HOXC8. The induction of UCP1 and CD137 were confirmed using immunocytochemistry. Lastly, Oxygen Consumption Rate (OCR) was measured using the Seahorse Bioanalyzer. High-dose isoproterenol increased OCR at multiple time points, leading to an increased total OCR when area under the curve was analyzed (p=0.06). Our research demonstrates that mature 3T3-L1 adipocytes upon stimulation can adopt a beige genotype and increase thermogenesis. Furthermore, these cells can be an efficacious model to understand the process of white to beige adipocyte transdifferentiation and to screen pharmaceutical/nutraceutical agents for beiging properties.
Available at: http://works.bepress.com/srujana_rayalam/35/