Figure 3.

Obesity scenario: transformation and/or adaptation of sphingolipid signaling under condition of metabolic stress (hypothetical scheme). Sphingolipid signaling pathway was proposed to alter during metabolic stress in obese organisms. Blood plasma of obese patients was characterized by dis-regulated S1P gradient, decreased levels of S1P in blood plasma, but higher S1P in specific cells and tissues [102,107,209,210]. Higher S1PR1 and S1PR3 levels were also detected [68]. However, these findings require further confirmation. Black arrows indicate directions of S1P/S1PRs effects. Question marks indicate the gaps in our knowledge of SphK/S1P/S1PRs axis.