Sphingosine-1-phosphate promotes erythrocyte glycolysis and oxygen release for adaptation to high-altitude hypoxia.
Nat Commun 2016;
7:12086. [PMID:
27417539 PMCID:
PMC4947158 DOI:
10.1038/ncomms12086]
[Citation(s) in RCA: 144] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 05/26/2016] [Indexed: 12/19/2022] Open
Abstract
Sphingosine-1-phosphate (S1P) is a bioactive signalling lipid highly enriched in mature erythrocytes, with unknown functions pertaining to erythrocyte physiology. Here by employing nonbiased high-throughput metabolomic profiling, we show that erythrocyte S1P levels rapidly increase in 21 healthy lowland volunteers at 5,260 m altitude on day 1 and continue increasing to 16 days with concurrently elevated erythrocyte sphingonisne kinase 1 (Sphk1) activity and haemoglobin (Hb) oxygen (O2) release capacity. Mouse genetic studies show that elevated erythrocyte Sphk1-induced S1P protects against tissue hypoxia by inducing O2 release. Mechanistically, we show that intracellular S1P promotes deoxygenated Hb anchoring to the membrane, enhances the release of membrane-bound glycolytic enzymes to the cytosol, induces glycolysis and thus the production of 2,3-bisphosphoglycerate (2,3-BPG), an erythrocyte-specific glycolytic intermediate, which facilitates O2 release. Altogether, we reveal S1P as an intracellular hypoxia-responsive biolipid promoting erythrocyte glycolysis, O2 delivery and thus new therapeutic opportunities to counteract tissue hypoxia.
The presence of the signalling lipid Sphingosine 1-phosphate (S1P) in erythrocytes has unclear physiological implications. Here the authors show that the S1P-generating enzyme Sphingosine kinase type 1 and its product S1P play an important role in the red blood cell adaptation to hypoxic environments in mice and humans.
Collapse