"Is the Brain Like a Battery?"... Inexpensive Lithium May Be the Key to Alzheimer's Treatment

Harvard Research Team Publishes Mouse Study in Nature
Effective Even in Small Amounts... Needs to Be Proven Through Clinical Trials

Research results have been published showing that lithium, a metallic element, has a significant effect in treating Alzheimer's dementia.

On August 6 (local time), the Washington Post (WP) reported that a research team led by Bruce Yankner, a professor of neurology at Harvard Medical School, discovered after seven years of research that lithium metal plays a major role in the treatment of Alzheimer's dementia. The team published their findings in the world-renowned journal Nature, demonstrating that administering small amounts of lithium orotate (a compound of lithium and orotic acid) to mice was able to restore brain function. Because lithium orotate is very inexpensive, there is growing anticipation that an affordable treatment for Alzheimer's may be developed.

The researchers found that when healthy mice were given food lacking in lithium, their synapses decreased and their memory declined. When these mice were administered lithium orotate, their memory recovered to the level of six-month-old young mice. However, Professor Yankner emphasized the importance of human clinical trials, stating, "We do not recommend taking lithium yet," because "the situation may change when moving from mice to humans." This is because excessive intake can cause serious side effects, such as kidney and thyroid damage.

Professor Yankner explained, "In healthy aged mice, lithium enhances memory function," and "among healthy elderly people, higher lithium levels are associated with better memory." The research team measured the levels of about 30 different metals in the brains and blood of three groups: cognitively healthy individuals, early-stage dementia patients, and patients with severe Alzheimer's disease. Lithium was the only metal to show significant differences in levels between the groups.

Lithium helps maintain the connections and communication between neurons, the nerve cells of the brain. It also contributes to the formation of myelin, the communication pathway between nerve cells, and assists microglia in clearing away cellular debris that interferes with brain function. When lithium is deficient, the formation of harmful amyloid beta protein aggregates and tau protein tangles accelerates. This disrupts communication between nerve cells, leading to Alzheimer's, and also traps lithium, preventing it from promoting brain function.

This study is significant in that it is the first to specifically explain the role of lithium in the brain, its effects on all major cell types in the brain, and the impact of lithium deficiency during old age on aging.

Additionally, the study shows that measuring lithium levels in the body could help identify the risk of developing Alzheimer's years before symptoms appear. This is because lithium levels can be measured via cerebrospinal fluid or blood tests, or through brain imaging.

Meanwhile, the number of Alzheimer's patients in the United States currently exceeds seven million and is estimated to reach 13 million by 2050. The drugs currently approved and used for the treatment of Alzheimer's are mainly antibody-based therapies targeting amyloid beta protein, such as Aduhelm (aducanumab) and Lecanemab (Leqembi), developed by Biogen of the United States and Eisai of Japan.

Lithium has been used as a mood stabilizer since the 19th century and was approved by the FDA as a treatment for bipolar disorder after the 1970s.