Exercise intensity affects circulating C1q/TNF-related proteins and follistatin-like 1 concentrations

Area of Science:

• Exercise Physiology
• Endocrinology
• Metabolic Health

Background:

• High-intensity endurance exercise is associated with lower metabolic disease mortality compared to moderate-intensity exercise.
• The underlying mechanisms, particularly the role of specific cytokines, remain unclear.
• Cytokines C1q/tumour necrosis factor-related protein (CTRP) 3, CTRP9, and follistatin-like 1 (FSTL1) are known to improve metabolic health and are secreted during exercise.

Purpose of the Study:

• To investigate the effect of exercise intensity on circulating concentrations of CTRP3, CTRP9, and FSTL1.
• To determine if high-intensity or moderate-intensity endurance exercise differentially affects these key metabolic cytokines.

Main Methods:

• Ten healthy men participated in a crossover study involving moderate-intensity (50% VO2max) and high-intensity (75% VO2max) cycling trials, matched for energy expenditure.
• Blood samples were collected pre-exercise, immediately post-exercise, and 120 minutes post-exercise.
• Concentrations of CTRP3, CTRP9, and FSTL1 were measured using standardized assays.

Main Results:

• High-intensity exercise (HIE) led to significant increases in circulating CTRP3, CTRP9, and FSTL1 post-exercise compared to pre-exercise levels.
• Moderate-intensity exercise (MIE) did not result in significant changes in these cytokine concentrations.
• The post-exercise increase in CTRP3, CTRP9, and FSTL1 was significantly greater in the HIE trial compared to the control (rest) trial.

Conclusions:

• Circulating concentrations of CTRP3, CTRP9, and FSTL1 are significantly elevated following high-intensity endurance exercise.
• Exercise intensity plays a crucial role in modulating the secretion of these beneficial metabolic cytokines.
• These findings suggest a potential mechanism linking high-intensity exercise to improved metabolic health via specific cytokine responses.