TY - JOUR A1 - Zeitler, Stefanie A1 - Ye, Lian A1 - Andreyeva, Aksana A1 - Schumacher, Fabian A1 - Monti, Juliana A1 - Nürnberg, Bernd A1 - Nowak, Gabriel A1 - Kleuser, Burkhard A1 - Reichel, Martin A1 - Fejtova, Anna A1 - Kornhuber, Johannes A1 - Rhein, Cosima A1 - Friedland, Kristina T1 - Acid sphingomyelinase - a regulator of canonical transient receptor potential channel 6 (TRPC6) activity JF - Journal of neurochemistry N2 - Recent investigations propose the acid sphingomyelinase (ASM)/ceramide system as a novel target for antidepressant action. ASM catalyzes the breakdown of the abundant membrane lipid sphingomyelin to the lipid messenger ceramide. This ASM‐induced lipid modification induces a local shift in membrane properties, which influences receptor clustering and downstream signaling. Canonical transient receptor potential channels 6 (TRPC6) are non‐selective cation channels located in the cell membrane that play an important role in dendritic growth, synaptic plasticity and cognition in the brain. They can be activated by hyperforin, an ingredient of the herbal remedy St. John’s wort for treatment of depression disorders. Because of their role in the context of major depression, we investigated the crosstalk between the ASM/ceramide system and TRPC6 ion channels in a pheochromocytoma cell line 12 neuronal cell model (PC12 rat pheochromocytoma cell line). Ca2+ imaging experiments indicated that hyperforin‐induced Ca2+ influx through TRPC6 channels is modulated by ASM activity. While antidepressants, known as functional inhibitors of ASM activity, reduced TRPC6‐mediated Ca2+ influx, extracellular application of bacterial sphingomyelinase rebalanced TRPC6 activity in a concentration‐related way. This effect was confirmed in whole‐cell patch clamp electrophysiology recordings. Lipidomic analyses revealed a decrease in very long chain ceramide/sphingomyelin molar ratio after ASM inhibition, which was connected with changes in the abundance of TRPC6 channels in flotillin‐1–positive lipid rafts as visualized by western blotting. Our data provide evidence that the ASM/ceramide system regulates TRPC6 channels likely by controlling their recruitment to specific lipid subdomains and thereby fine‐tuning their physical properties. KW - acid sphingomyelinase KW - antidepressants KW - ceramide KW - hyperforin KW - lipid rafts KW - TRPC6 Y1 - 2019 U6 - https://doi.org/10.1111/jnc.14823 SN - 0022-3042 SN - 1471-4159 VL - 150 IS - 6 SP - 678 EP - 690 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Gulbins, Erich A1 - Palmada, Monica A1 - Reichel, Martin A1 - Lueth, Anja A1 - Boehmer, Christoph A1 - Amato, Davide A1 - Mueller, Christian P. A1 - Tischbirek, Carsten H. A1 - Groemer, Teja W. A1 - Tabatabai, Ghazaleh A1 - Becker, Katrin Anne A1 - Tripal, Philipp A1 - Staedtler, Sven A1 - Ackermann, Teresa F. A1 - van Brederode, Johannes A1 - Alzheimer, Christian A1 - Weller, Michael A1 - Lang, Undine E. A1 - Kleuser, Burkhard A1 - Grassme, Heike A1 - Kornhuber, Johannes T1 - Acid sphingomyelinase-ceramide system mediates effects of antidepressant drugs JF - Nature medicine N2 - Major depression is a highly prevalent severe mood disorder that is treated with antidepressants. The molecular targets of antidepressants require definition. We investigated the role of the acid sphingomyelinase (Asm)-ceramide system as a target for antidepressants. Therapeutic concentrations of the antidepressants amitriptyline and fluoxetine reduced Asm activity and ceramide concentrations in the hippocampus, increased neuronal proliferation, maturation and survival and improved behavior in mouse models of stress-induced depression. Genetic Asm deficiency abrogated these effects. Mice overexpressing Asm, heterozygous for acid ceramidase, treated with blockers of ceramide metabolism or directly injected with C16 ceramide in the hippocampus had higher ceramide concentrations and lower rates of neuronal proliferation, maturation and survival compared with controls and showed depression-like behavior even in the absence of stress. The decrease of ceramide abundance achieved by antidepressant-mediated inhibition of Asm normalized these effects. Lowering ceramide abundance may thus be a central goal for the future development of antidepressants. Y1 - 2013 U6 - https://doi.org/10.1038/nm.3214 SN - 1078-8956 VL - 19 IS - 7 SP - 934 EP - + PB - Nature Publ. Group CY - New York ER -