Abstract
Curcumin (Cur) has been found to improve cognitive function at high doses. However, contradictory findings have also been reported, mainly due to its low water solubility and very low bioavailability. We previously used an amorphous individual dispersion technique to develop a novel highly bioavailable Cur formulation (HC) for use as a dietary supplement. Because exercise also improves brain function, food-derived factors and exercise might synergize to boost cognitive function. After confirming that HC alone (4.5 mg Cur/kg [equivalent to 15 mg HC/kg]) did not improve cognitive function, we demonstrated that the combination of HC, but not native Cur, and voluntary exercise for 4 weeks significantly improved spatial memory and learning in mice in the novel location-recognition and passive avoidance tests, even though exercise alone did not have this effect. This effect was related to elevated expression of brain-derived neurotrophic factor via activation of two related pathways. HC, and not native Cur, may help to improve learning and memory functions in both younger and older adults as a dietary supplement during exercise.