[Endogenous nerve growth factor in patients with Alzheimer s disease]

Nerve growth factor (NGF) is the best characterized neurotrophic polypeptide. Initially it was postulated that alterations in the expression of NGF within its production sites may be responsible for the consistent atrophy and loss of cholinergic basal forebrain neurons in dementing illness such as Alzheimer s Disease (AD).

We analyze the NGF concentration in serum from control and patients with AD in order to elucidate something alteration in this fluid related with AD neuropathology.

We applied a twosite enzyme immunoassay to determine NGF levels in sera of patients with AD.

Sera from Alzheimer s patients (36+/-7 pg/ml) showed slight but non significant reduction in NGF levels when compared with age related controls (66+/-18 pg/ml). On the another hand, the NGF concentrations in AD patients and control subjects to the sex were following: female AD patients showed a mean of 33.27+/-10.43 pg/ml vs 57.83+/-22 pg/ml founded in female controls, while the mean value for male AD patients was 40.87+/-12.29 pg/ml vs 37.47+/-12.28 pg/ml for the male controls. In all the cases studied, no significant differences were observed according to Student t-Test.

Even when no significant differences were observed between controls and AD patients, the results show a tendency NGF concentration decrease in this illness. Certainly, NGF is produced not only in the forebrain but throughout the body, for this reason, more studies, including the analysis of cerebrospinal fluid would be useful to define the real relationship between NGF concentration changes in serum and AD-related changes in endogenous NGF concentrations, taking into account increasing levels by exogenous NGF administration could still be useful in maintaining the cholinergic neurons.