Effect of long-term carnosine/anserine supplementation on iron regulation after a prolonged running session.

[Purpose] Exercise-induced hemolysis, which is caused by metabolic and/or mechanical stress during exercise, is considered a potential factor for upregulating hepcidin. Intramuscular carnosine has multiple effects including antioxidant activity. Therefore, this study aimed to determine whether long-term carnosine/anserine supplementation modulates exercise-induced hemolysis and subsequent hepcidin elevation. [Methods] Seventeen healthy male participants were allocated to two different groups: participants consuming 1,500 mg/day of carnosine/anserine supplements (n = 9, C+A group) and participants consuming placebo powder supplements (n = 8, PLA group). The participants consumed carnosine/anserine or placebo supplements daily for 30.7 ± 0.4 days. They performed an 80-running session at 70% V̇O2peak pre-and post-supplementation. Iron regulation and inflammation in response to exercise were evaluated. [Results] Serum iron concentrations significantly increased after exercise (p < 0.01) and serum haptoglobin concentrations decreased after exercise in both groups (p < 0.01). No significant differences in these variables were observed between pre-and post-supplementation. Serum hepcidin concentration significantly increased 180 min after exercise in both groups (p < 0.01). The integrated area under the curve of hepcidin significantly decreased after supplementation (p = 0.011) but did not vary between the C+A and PLA groups. [Conclusion] Long-term carnosine/anserine supplementation does not affect iron metabolism after a single endurance exercise session.