Drugmakers have plans to counter various forms of dementia, ranging from that found in alzheimer’s disease to the common memory loss that occurs with aging (age-associated memory impairment). These compounds, a selection of which are included here and many of which have yet to reach late-stage clinical trials, might eventually be used by healthy people who want to improve mental functioning, although questions remain about how safe or effective they would be for people without a cognitive deficit.
Drug Class: Nicotinic acetylcholine receptor activators. Either increase levels of the neurotransmitter acetylcholine in the synapse of a neuron, or the drugs themselves take the place of acetylcholine in the synapse to activate the nicotinic acetylcholine receptor, enhancing attention, memory and other facets of cognition. Developer: Abbott, CoMentis, EnVivo, Targacept/AstraZeneca and Xytis.
Drug Class: Ampakines. Act on AMPA receptors to strengthen neuronal responses to the neurotransmitter glutamate, activity that should facilitate the laying down of long-term memories. Developer: Cortex Pharmaceuticals; Eli Lilly, GlaxoSmithKline/ Neurosearch, Organon, Pfizer and Servier.
Drug Class: Phosphodiesterase (PDE) Inhibitors. One type of PDE blocker enables a signaling molecule, cyclic AMP, to remain active longer in brain neurons, thereby enhancing the activity of a protein called CREB that is important to long-term memory. Developer: Helicon Therapeutics, Hoffmann–La Roche and Merck.
Drug Class: Antihistamines. Block a histamine receptor called the H3 receptor, thereby improving wakefulness, attention and cognition. One drug that interacts with the H1 receptor, developed as a treatment for hay fever in Russia, has entered late-stage clinical trials as an enhancer. Developer: GlaxoSmithKline, Johnson & Johnson and Medivation/Pfi zer.
Source of Information : Scientific American October 2009
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