Oxygen is a critical regulator of cellular metabolism and function in cell culture

Abstract

SUMMARYCell culture, the workhorse of biomedical research, is generally considered to be hyperoxic. However, oxygen consumption by cells is underappreciated. High cellular respiration rates can rapidly deplete oxygen, resulting in local hypoxia. Increasing pericellular oxygen levels rewired the metabolism of multiple post-mitotic cell-lines, both in monolayer and organoid culture. Under standard conditions, cultured adipocytes are hypoxic and highly glycolytic. Increased oxygen availability diverted glucose flux toward mitochondria and increased lipogenesis from glucose-derived carbon. These metabolic changes were coupled to thousands of gene expression changes, and rendered adipocytes more sensitive to insulin and lipolytic stimuli. Importantly, pathway analyses revealed increasing oxygen tension madein vitroadipocytes more similar toin vivoadipose tissue. hPSC-derived hepatocytes and cardiac organoids were also functionally enhanced by increased oxygen. Our findings suggest that oxygen is limiting in many standard cell culture systems, and highlight how controlling oxygen availability can improve translatability of cell models.