The Antioxidant NAC May Enhance Cognitive Health

By VRP Staff

A new study investigated the potential neuro-protective activity of N-acetyl-cysteine (NAC). In the United States, an estimated 5.3 million people have Alzheimer’s disease, and this degenerative disease is currently the seventh-leading cause of death. Alzheimer’s disease is also the most common form of dementia, accounting for 50 to 70 percent of dementia cases with memory loss and decreased intellectual abilities that are serious enough to interfere with daily life.

Alzheimer’s disease is a progressive brain disease in which plaques containing a protein fragment called amyloid beta develop between nerve cells. Additionally, tangles, which contain a protein known as tau, develop inside cells beginning in areas important in learning and memory and then spreading to other regions. Some studies indicate an association between an increased risk of developing Alzheimer’s disease with the intake of metals such as aluminum.

In this new study, investigators examined the effect of NAC in animal models of cognitive dysfunction; specifically, rats were treated with aluminum, a neurotoxin that induced cognitive dysfunction similar to that of Alzheimer’s disease. Previous research indicates that chronic aluminum exposure induces oxidative stress and increases amyloid beta levels. The rats received aluminum treatment or NAC pre-treatment plus aluminum for 6 weeks. During the third and sixth week of the study, the rats were evaluated for both behavioral activities and cognitive function using the Morris water maze and the elevated plus maze task.

The results showed that aluminum administration induced poor retention of memory and increased oxidative damage in the brain. Additionally, aluminum treatment caused a significant increase in acetylcholinesterase activity, which is an enzyme that breaks down the neurotransmitter acetylcholine. Acetylcholine is a chemical in the brain that plays a key role in memory, learning and many other brain functions; significantly, lower levels of acetylcholine are associated with Alzheimer’s disease.

NAC pre-treatment of the rats receiving aluminum treatment resulted in significantly improved memory retention during tasks, decreased oxidative damage and reduced acetylcholinesterase activity.

The study authors concluded, “The study suggests a neuroprotective effect of N-acetyl cysteine against aluminum-induced cognitive dysfunction and oxidative damage.”

Reference:

Prakash A, Kumar A. Effect of N-acetyl cysteine against aluminium-induced cognitive dysfunction and oxidative damage in rats. Basic Clin Pharmacol Toxicol. 2009 Aug;105(2):98-104.