Two pore potassium channel trek-1 (k2p2.1) regulates nlrp3 inflammasome activity in macrophages

Am J Physiol Lung Cell Mol Physiol. 2024 Jan 22. doi: 10.1152/ajplung.00313.2023. Online ahead of print.ABSTRACTBecause of the importance of potassium efflux in inflammasome activation, we investigated the role of the two-pore potassium (K2P) channel TREK-1 in macrophage inflammasome activity. Using primary alveolar macrophages (AMs) and bone marrow derived macrophages (BMDMs) from wild type (wt) and TREK-1-/- mice, we measured responses to inflammasome priming (using LPS) and activation (LPS +ATP). We measured IL-1β, caspase-1, and NLRP3 via ELISA and western blot. A membrane-permeable potassium indicator was used to measure potassium efflux during ATP exposure, and a fluorescence-based assay was used to assess changes in membrane potential. Inflammasome activation induced by LPS+ATP increased IL-1β secretion from wt AMs, whereas activation was significantly reduced in TREK-1-/- AMs. Priming of BMDMs using LPS was not affected by either genetic deficiency or pharmacological inhibition of TREK-1 with Spadin. Cleavage of caspase-1 following LPS+ATP treatment was significantly reduced in TREK-1-/- BMDMs. The intracellular potassium concentration in LPS primed wt BMDMs was significantly lower compared with TREK-1-/- BMDMs or wt BMDMs treated with Spadin. Conversely, activation of TREK-1 with BL1249 caused a decrease in intracellular potassium in wt BMDMs. Treatment of LPS-primed BMDMs with ATP caused a rapid reduction in intracellular potassium levels, with the largest change ...
Source: American Journal of Physiology. Lung Cellular and Molecular Physiology - Category: Cytology Authors: Source Type: research