| Although beta-amyloid (Ab) has been regarded as the principal toxic factor in the pathogenesis of Alzheimer’s disease (AD), it plays important physiological roles in phenomena such as
neuron survival, synaptic plasticity, and memory formation. There are numerous plausible reasons
to assume that all of the mentioned pathological and physiological functions of Ab may be partially
mediated via alpha 7 nicotinic acetylcholine receptor (nAChR). Agonistic and antagonistic aspects
of Ab on nAChRs may explain this paradox in peptide–receptor function. It seems that Ab shows
antagonistic effects on a7 nAChR in a dose-dependent manner, and its pathologic function may
partially correlate with antagonization of the receptor.
If this hypothesis is supported, the related mechanisms of neurotoxicity, neuroprotection, memory formation, and AD pathogenesis might be identified. In addition, such knowledge helps make a
more valid interpretation of neuron signaling and a better design of AD animal models. In addition,
it may provide new insights into AD therapy development via reducing the amount of Ab and
inhibiting peptide aggregation. |