Plain language summary
Shiitake (Lentinus edodes) is a popular culinary and medicinal mushroom. It contains numerous active compounds including ergothioneine which has anti-inflammatory and antioxidant properties. This study evaluated the antioxidant and anti-inflammatory effect of shiitake extract in healthy men exposed to exercise-induced muscle damage. Fourteen healthy males participated in this placebo-controlled crossover study. Subjects ingested shiitake extract or placebo for 10 days prior to exercise, with a 30 day period between the two phases of the crossover. Bloods were drawn at 20 minutes, 24 hours and 48 hours after exercise. There was no statistically significant difference between the shiitake and the placebo group in the inflammation related parameters measured. But there was a significant change in certain compounds suggesting an increased antioxidant activity in the shiitake group. The authors conclude that shiitake does not affect the inflammatory response following exercise but has antioxidant action, and that further studies are needed to make recommendations for use of shiitake by athletes.
Abstract
The shiitake (Lentinus edodes) extract is purported to have potent antioxidant, anti-inflammatory and regenerative properties due to presence of many bioactive compounds such as ergothioneine. This study was designed to assess the antioxidant and anti-inflammatory activity of shiitake extract in healthy men exposed to exercise-induced skeletal muscles damage. Subjects ingested shiitake mushroom extract (700 mg, two times per day) or placebo for 10 days prior to two separate exercise trials (crossover study). The exercise session involved 90 min run at 65% VO2max (0% gradient) and 15-min eccentric phase at 65% VO2max (-10% gradient). Subjects experienced creatine kinase (peak 461±206 IU/L) and leukocytes (peak 9.82 x 103/μL) elevations indicating muscle damage and inflammation. Exercise altered plasma IL-6 (peak 5.29±0.78 pg/mL), IL-10 (peak 24.75±6.22 pg/mL) and IL-1β (peak 0.54±0.09 pg/mL) levels but did not affect tumour necrosis factor α (TNF-α) level relative to baseline. Shiitake extract did not demonstrate any effect on immune cells number and inflammatory mediators level, with the exception of IL-10. Thiol redox status (GSHtotal-2GSSG/GSSG) and niric oxide (NO) concentration increased after shiitake extract whereas H2O2 and 8-isoprostanes did not change. In conclusion, shiitake mushroom extract had no effect on markers of inflammation following prolonged eccentric exercise but demonstrated an antioxidant activity through the regulation of nitric oxide concentration and thiol redox status.
Methodological quality
Jadad score
:
2
Allocation concealment
:
Not applicable
