Aquaporins (AQPs) are membrane water/
glycerol channels that are involved in many physiological processes. Their primary function is to facilitate the bidirectional transfer of water and small solutes across
biological membranes in response to osmotic gradients.
Aquaglyceroporins, a subset of the AQP family, are the only mammalian
proteins with the ability to permeate
glycerol. For a long time, AQP7 has been the only
aquaglyceroporin associated with the adipose tissue, which is the major source of circulating
glycerol in response to the energy demand. AQP7 dysregulation was positively correlated with
obesity onset and adipocyte
glycerol permeation through AQP7 was appointed as a novel regulator of adipocyte metabolism and whole-body fat mass. Recently, AQP3, AQP9, AQP10 and AQP11 were additionally identified in human adipocytes and proposed as additional
glycerol pathways in these cells. This review contextualizes the importance of
aquaglyceroporins in adipose tissue biology and highlights
aquaglyceroporins' unique structural features which are relevant for the design of effective therapeutic compounds. We also refer to the latest advances in the identification and characterization of novel
aquaporin isoforms in adipose tissue. Finally, considerations on the actual progress of
aquaporin research and its implications on
obesity therapy are suggested.