Continuous exercise training and curcumin attenuate changes in brain-derived neurotrophic factor and oxidative stress induced by lead acetate in the hippocampus of male rats

Context: For many years it has been known that lead is life-threatening, not only as an air pollutant but also because of it has been associated with several conditions including neurodegenerative disease. Curcumin (the principal curcuminoid found in turmeric) has demonstrated potent antioxidant properties. Objective: We investigated neuroprotective effects of endurance exercise and/or curcumin on lead acetate-induced neurotoxicity in the rat hippocampus. Materials and methods: Forty male Wistar rats were randomly divided into five groups: 1) lead acetate, 2) curcumin, 3) training, 4) training + curcumin, and 5) control. The rats in the training groups performed treadmill running five times a week for 8 weeks (15-22 m/min, 25-64 min). All groups except control received lead acetate (20 mg/kg), whereas the control group received curcumin solution (ethyl oleate). In addition, the curcumin and training + curcumin groups received curcumin solution (30 mg/kg) intraperioneally. Results: Lead acetate resulted in a significantly increase in the malondialdehyde (MDA) in plasma (72%), but not significant in hippocampus (59%). In addition, it led to significantly decreased brain-derived neurotrophic factor in hippocampus (17%) and total antioxidant capacity (27%), as compared to control group. Treadmill running, curcumin supplementation or both resulted in a significant decrease in hippocampus MDA (17, 20, 31%, respectively) and plasma MDA (60, 22, 71%) and also, significantly increased brain-derived neurotrophic factor (76, 45, 94%) and total antioxidant capacity (47.13, 47.11, 61%) levels, as compared to lead acetate group. Discussion and Conclusion: These results provide a rationale for an inhibitory role of curcumin and regular exercise in the attenuation of lead-induced neurotoxicity.