Endurance training selectively increases high-density lipoprotein-bound sphingosine-1-phosphate in the plasma

Area of Science:

• Cardiovascular Physiology
• Lipid Metabolism
• Exercise Science

Background:

• Sphingosine-1-phosphate (S1P) is a bioactive lipid in human plasma, primarily bound to HDL and albumin.
• HDL-bound S1P exhibits cardioprotective and anti-atherogenic effects.
• Previous studies indicated higher plasma S1P in endurance-trained athletes.

Purpose of the Study:

• To investigate the impact of endurance training on S1P metabolism in blood.
• To determine if exercise training alters plasma S1P concentrations and its distribution.
• To explore the cellular mechanisms behind exercise-induced changes in S1P.

Main Methods:

• Eight-week rowing ergometer training program for 13 healthy, untrained males.
• Blood samples collected pre-training and post-training.
• Analysis of total plasma S1P and S1P fractions (HDL-bound).
• Assessment of sphingosine kinase activity and S1P release from erythrocytes and platelets.

Main Results:

• Total plasma S1P concentration significantly increased after 8 weeks of training.
• Training selectively elevated HDL-bound S1P levels.
• Increased sphingosine kinase activation in erythrocytes and platelets was observed.
• Enhanced S1P release from red blood cells correlated with increased HDL-bound S1P.

Conclusions:

• Endurance training enhances plasma sphingosine-1-phosphate (S1P) levels, particularly HDL-bound S1P.
• The observed increase is associated with improved S1P metabolism in blood cells.
• Elevated HDL-bound S1P may contribute to the cardiovascular benefits of regular physical activity.