Prior studies have suggested that metformin, often used as a first-line treatment for people with type 2 diabetes (T2D0, could confer benefits for Rett syndrome. In particular, prior studies found that metformin improved and restored brain energy production in murine (mice) models of Rett syndrome. According to Rett Syndrome News, another study—published in Neuropharmacology—found that longer-term metformin treatment also improved cognition and cognitive function. 

Within this study, researchers treated 1-year-old symptomatic female mice models of Rett syndrome with metformin over a 4-month period. The same therapy was also given to healthy control mice. After running a number of tests, the researchers found that:

• Metformin did not improve memory, motor coordination, or overall health in the Rett models. 
• The treatment helped to restore ATP production in the brain, restore mitochondrial activity, improve antioxidant defense, and reduce overall oxidative stress. 
• Additionally, metformin improved cognitive function and flexibility, allowing the mouse more behavioral control. 
• This therapy was effective in mice models even in later disease stages. 

It is currently unclear exactly how and why metformin benefits cognition. Some researchers hypothesize that it involves the regulation and modulation of mitochondrial function. While the findings are promising thus far, more research is needed to underscore this data and further evaluate the treatment’s impact. 

Rett Syndrome: An Overview

So what exactly is Rett syndrome? This rare genetic neurodevelopmental disorder results from an X chromosome mutation. It is almost never inherited and most often occurs as a spontaneous mutation. Rett syndrome primarily affects girls, though there has been a push for more research into boys living with this disorder. Symptoms often manifest between 12-18 months of age and may include:

• Slowed growth
• Microcephaly (abnormally small head size)
• Repetitive hand movements such as wringing, squeezing, or clapping
• Irritability 
• Hyperventilation
• Unusual eye movements
• Sleep disturbances
• Irregular heartbeat 
• Muscle weakness or stiffness
• Loss of language skills (or no language development) 
• Uncoordinated breathing
• Seizures

There is no cure for Rett syndrome. Treatment options include anti-seizure medication, behavioral therapy, physical therapy, speech therapy, and occupational therapy.