Euscaphic acid relieves fatigue by enhancing anti-oxidative and anti-inflammatory effects

Oxidative stress and inflammation are involved in chronic fatigue. Euscaphic acid (EA) is an active compound of Eriobotrya japonica (Loquat) and has anti-oxidative effect.

The goal of present study is to prove whether EA could relieve fatigue through enhancing anti-oxidant and anti-inflammatory effects in in vitro/in vivo models.

EA notably improved activity of superoxide dismutase (SOD) and catalase (CAT), while EA reduced levels of malondiadehyde (MDA) and inflammatory cytokines without cytotoxicity in H₂O₂-stimulated in myoblast cell line, C2C12 cells. EA significantly reduced levels of fatigue-causing factors such as lactate dehydrogenase (LDH) and creatin kinase (CK), while EA significantly incresed levels of anti-fatigue-related factor, glycogen compared to the H₂O₂-stimulated C2C12 cells. In treadmill stress test (TST), EA significantly enhanced activities of SOD and CAT as well as exhaustive time and decreased levels of MDA and inflammatory cytokines. After TST, levels of free fatty acid, citrate synthase, and muscle glycogen were notably enhanced by oral administration of EA, but EA decreased levels of lactate, LDH, cortisol, aspartate aminotransferase, alanine transaminase, CK, glucose, and blood urea nitrogen compared to the control group. Furthermore, in forced swimming test, EA significantly increased levels of anti-fatigue-related factors and decreased excessive accumulations of fatigue-causing factors.

Therefore, the results indicate that potent anti-fatigue effect of EA can be achieved via the improvement of anti-oxidative and anti-inflammatory properties, and this study will provide scientific data for EA to be developed as a novel and efficient component in anti-fatigue health functional food.