Soluble Interleukin-6 Receptor Regulates Interleukin-6-Dependent Vascular Remodeling in Long-Distance Runners.

Area of Science:

• Exercise physiology
• Cardiovascular research
• Molecular biology

Background:

• Interleukin-6 (IL-6) and its soluble receptor (sIL-6R) are implicated in inflammation and vascular remodeling.
• The impact of training load on exercise-induced IL-6 and sIL-6R and their connection to vascular changes remains unclear.

Purpose of the Study:

• To investigate the effect of training load on plasma IL-6 and sIL-6R levels post-marathon.
• To explore the relationship between these cytokines and vascular remodeling, specifically aortic diameter.
• To determine the role of sIL-6R in regulating IL-6-mediated vascular smooth muscle cell (VSMC) migration.

Main Methods:

• Plasma IL-6, sIL-6R, and sgp130 levels were measured in low-training (LT) and high-training (HT) marathon runners before and after a marathon.
• Aortic diameter was assessed using echocardiography.
• In vitro studies examined the effect of sIL-6R on IL-6-induced VSMC migration and proliferation.

Main Results:

• Plasma IL-6 and sIL-6R increased post-marathon in both LT and HT groups.
• HT athletes exhibited higher post-race sIL-6R levels compared to LT athletes.
• A positive correlation was found between ascending aorta diameter and IL-6 levels, modulated by training load and training duration.
• In vitro, IL-6 stimulated VSMC migration, an effect inhibited by sIL-6R.

Conclusions:

• Endurance exercise, like marathon running, induces vascular remodeling.
• Elevated sIL-6R in high-training athletes may play a regulatory role in IL-6-dependent vascular remodeling.
• sIL-6R potentially modulates IL-6-induced VSMC migration, offering a mechanism for regulating vascular adaptation to exercise.