Serum BDNF and NGF Modulation by Olive Polyphenols in Alcoholics during Withdrawal

Many studies have suggested possible relationships between the neurotrophins brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) and alcohol addiction. Previous reports demonstrated severe changes in these neurotrophins in the serum of alcohol dependent patients and during withdrawal. Alcohol dependence syndromes during consumption and/or withdrawal are also characterized by elevated oxidative stress. Polyphenols, including olive polyphenols, are natural compounds known to possess marked antioxidant properties. Thus, this study was carried out in order to verify the effects of a blend of olive polyphenols supplementation containing mostly hydroxytyrosol (50 mg/day for 15 consecutive days) in alcoholic men during withdrawal on serum BDNF and NGF. As controls a group of alcohol dependent patients received sucrose tablets as placebo. BDNF and NGF were measured by ELISA on day 1, 3, 7 and 15 of the detoxification period. Some parameters of oxidative stress were analyzed too as free oxygen radicals defense (FORD) and free oxygen radicals test (FORT). No differences in oxidative status due to polyphenols were found. However, withdrawal elicited a mild increase in BDNF over two weeks that was counteracted on day 3 by polyphenols. As for NGF no effects of polyphenols supplementation were discovered to antagonize the expected NGF serum elevation during withdrawal. In conclusion the present data may indicate that monitoring serum BDNF and/or NGF in alcoholics undergoing detoxification could contribute to characterize alcohol dependence profiles to improve recovery processes throughout also antioxidant compounds.