Nefiracetam is a
nootropic
Nootropics ( , or ) (colloquial: smart drugs and cognitive enhancers, similar to adaptogens) are a wide range of natural or synthetic dietary supplement, supplements or drugs and other substances that are claimed to improve cognitive function ...
drug of the
racetam
Racetams are a class of drugs that share a pyrrolidone nucleus. Some, such as piracetam, aniracetam, oxiracetam, pramiracetam and phenylpiracetam are considered nootropics. Others such as levetiracetam, brivaracetam, and seletracetam are ant ...
family. Preliminary research suggests that it may possess certain
antidementia properties in rats.
Effects
Nefiracetam's cytoprotective actions are mediated by enhancement of
GABAergic
In molecular biology and physiology, something is GABAergic or GABAnergic if it pertains to or affects the neurotransmitter GABA. For example, a synapse is GABAergic if it uses GABA as its neurotransmitter, and a GABAergic neuron produces GABA. A ...
,
cholinergic
Cholinergic agents are compounds which mimic the action of acetylcholine and/or butyrylcholine. In general, the word " choline" describes the various quaternary ammonium salts containing the ''N'',''N'',''N''-trimethylethanolammonium cati ...
, and
monoaminergic
Monoaminergic means "working on monoamine neurotransmitters", which include serotonin, dopamine, norepinephrine, epinephrine, and histamine.
A monoaminergic, or monoaminergic drug, is a chemical, which functions to directly modulate the ser ...
neuronal systems. Preliminary studies suggest that it improves apathy and motivation in post-stroke patients. It may also exhibit antiamnesia effects for the Alzheimer's type and cerebrovascular type of dementia. In addition, research in animal models suggests antiamnesic effects against a number of memory impairing substances, including: ethanol, chlorodiazepoxide, scopolamine, bicuculline, picrotoxin, and cycloheximide.
Pharmacology
Unlike other racetams, nefiracetam shows high
affinity for the
GABAA receptor (
IC50) = 8.5 nM), where it is presumed to be an
agonist
An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the ag ...
.
It was able to potently inhibit 80% of
muscimol
Muscimol (also known as agarin or pantherine) is one of the principal psychoactive constituents of '' Amanita muscaria'' and related species of mushroom. Muscimol is a potent and selective orthosteric agonist for the GABAA receptors and displa ...
binding to the GABA
A receptor, although it failed to displace the remaining 20% of specific muscimol binding.
Nefiracetam is able to reverse the
amnesia
Amnesia is a deficit in memory caused by brain damage or disease,Gazzaniga, M., Ivry, R., & Mangun, G. (2009) Cognitive Neuroscience: The biology of the mind. New York: W.W. Norton & Company. but it can also be caused temporarily by the use ...
caused by the GABA
A receptor antagonists
picrotoxin and
bicuculline
Bicuculline is a phthalide-isoquinoline compound that is a light-sensitive competitive antagonist of GABAA receptors. It was originally identified in 1932 in plant alkaloid extracts and has been isolated from '' Dicentra cucullaria'', ''Adlumia ...
in mice, although it failed to prevent
seizure
An epileptic seizure, informally known as a seizure, is a period of symptoms due to abnormally excessive or synchronous neuronal activity in the brain. Outward effects vary from uncontrolled shaking movements involving much of the body with lo ...
s induced by these drugs.
Concerns
Studies of long-term consumption of nefiracetam in humans and primates have shown it to have no toxicity.
However, animals which metabolize nefiracetam differently from humans and primates are at risk for renal and testicular
toxicity. Dogs especially are particularly sensitive, which has been shown to be caused by a specific metabolite, M-18.
Higher doses than those in dogs were needed to cause testicular toxicity in rats, although no toxicity was seen in monkeys. Additionally, there has been no evidence of toxicity during clinical trials.
See also
*
Racetams
Racetams are a class of drugs that share a pyrrolidone nucleus. Some, such as piracetam, aniracetam, oxiracetam, pramiracetam and phenylpiracetam are considered nootropics. Others such as levetiracetam, brivaracetam, and seletracetam are ant ...
*
Guvacine
*
Phenibut
Phenibut, sold under the brand names Anvifen, Fenibut, and Noofen among others, is a central nervous system depressant with anxiolytic effects, and is used to treat anxiety, insomnia, and for a variety of other indications. It is usually take ...
References
{{GABAA receptor modulators
Racetams
Acetanilides
GABAA receptor agonists