Cacoa Prevents Degeneration of Dopamine Neurons and Motor Impairment Caused by Rotenone

We investigated the effects of cacoa powder on oxidative stress and neurodegeneration in rotenone-induced Parkinson’s disease in mice. Rotenone was given subcutaneously at 1.5 mg/kg, every other day for two weeks and mice were treated at the same time with the cacoa at 1 and 2 g/kg, or L-dopa at 25 mg/kg, orally once a day. The control group received the vehicle (DMSO). Oxidative stress biomarkers; malondialdehyde (MDA), reduced glutathione (GSH) and nitric oxide (NO) were measured in brain tissue. Behavioral testing for motor performance and histologic study of the brain were also done. Results indicated that rotenone led to significant elevations in brain MDA and NO and this was accompanied by a marked GSH depletion. Mice exhibited impaired grip strength, motor balance and coordination in the wire hanging, wood walking, and stair tests. The histological study revealed marked decrease in number and size of pigmented cells in substantia nigra and an increase in the number of deeply stained neurons and karyorrhexis in the cerebral cortex and hippocampus after rotenone injection. Treatment with cacoa reduced brain MDA, NO and increased GSH levels and alleviated the motor deficits induced by rotenone. Cacoa given at 2 g/kg increased the size of pigmented cells in the substantia nigra, decreased the number of deeply stained neurons in hippocampus, while most of cortical neurons appeared normal. These results indicate that cacoa provides protection against rotenone-induced neurotoxicity and this involves an antioxidant action.