Changes in thioredoxin concentrations: an observation in an ultra-marathon race.
OBJECTIVE
Changes in plasma thioredoxin (TRX) concentrations before, during, and after a 130-km endurance race were measured with the aim of elucidating the relationship between exercise and oxidative stress (OS).


METHODS
Blood samples were taken from 18 runners participating in a 2-day-long 130-km ultra-marathon during the 2 days of the race and for 1 week thereafter. There were six sampling time points: at baseline, after the goal had been reached on the first and second day of the endurance race, respectively, and on 1, 3, and 5/6 days post-endurance race. The samples were analyzed for plasma TRX concentrations, platelet count, and blood lipid profiles.


RESULTS
Concentrations of plasma TRX increased from 17.9 ± 1.2 ng/mL (mean ± standard error of the mean) at baseline to 57.3 ± 5.0 ng/mL after the first day's goal had been reached and to 70.1 ± 6.9 ng/mL after the second day's goal had been reached; it then returned to the baseline level 1 day after the race. Platelet counts of 21.3 ± 1.2 × 10(4) cell/μL at baseline increased to 23.9 ± 1.5 × 10(4) cells/μL on Day 1 and to 26.1 ± 1.0 × 10(4) cells/μL on Day 2. On Day 7, the platelet counts had fallen to 22.1 ± 1.2 × 10(4) cell/μL. There was a significant positive correlation between plasma TRX and platelet count.


CONCLUSIONS
These data suggest that plasma TRX is an OS marker during physical exercise. Further studies are needed to determine the appropriate level of exercise for the promotion of health.
Marumoto
Mitsuhiro
M
Department of Public Health, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan. Marumoto_Mitsuhiro@takeda.co.jp
Suzuki
Sadao
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Hosono
Akihiro
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Arakawa
Kazuyuki
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Shibata
Kiyoshi
K
Fuku
Mizuho
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Goto
Chiho
C
Tokudome
Yuko
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Hoshino
Hideki
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Imaeda
Nahomi
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Kobayashi
Masaaki
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Yodoi
Junji
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Tokudome
Shinkan
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