In a new study, naturally occurring molecule N-acetylcysteine shows benefits in a clinical trial for multiple sclerosis. Researchers found improvements in brain metabolism, particularly in areas that support cognition such as the frontal and temporal lobes in patients with MS. In addition, patients reported qualitative improvements in their cognitive and attention focusing abilities.

Current treatments for MS are generally limited to trying to slow the progression of the disease by preventing new brain lesions from occurring. However, these approaches do not help the neurons that have already been affected by the disease process. While the primary event of MS results from an immunological process that targets the white matter, the actual damage to neurons may be due in large part from oxidative stress caused by the immune reaction. N-acetylcysteine is an oral supplement, and also comes in an intravenous form that is used to protect the liver in acetaminophen overdose. Several initial studies have shown that N-acetylcysteine administration increases glutathione levels in the brain. Because glutathione is an antioxidant, researchers have proposed that it could reduce the oxidative stress from the immune reaction, though it's unclear whether it would improve the function of neurons. The current study tested this by tracking cerebral glucose metabolism on positron emission tomography brain, as a proxy for normal neuronal function.

Researchers at the Department of Integrative Medicine and Nutritional Sciences, as well as the Departments of Neurology and Radiology, at Thomas Jefferson University, evaluated 24 patients with MS who continued their current treatment and were placed into two groups – the first group received a combination of oral and intravenous (IV) N-acetylcysteine for two months (in addition to their current treatment program); and the second group, the control patients, received only their standard-of-care treatment for MS for two months. Those patients in the active group received 50mg/kg N-acetylcysteine intravenously once per week and 500mg N-acetylcysteine orally 2x per day on the non-IV days.

All patients underwent brain scanning using FDG PET imaging which measures the amount of glucose metabolism in the neurons throughout the brain. This test was used to determine the level of neuronal recovery. Patients were evaluated initially and after two months of either receiving the N-acetylcysteine or standard of care therapy. Patients were also evaluated clinically using several different measures of brain function and quality of life.

Compared to controls, the patients receiving N-acetylcysteine had significant improvements in brain metabolism in the caudate, inferior frontal gyrus, lateral temporal gyrus, and middle temporal gyrus as measured by FDG PET imaging. These areas are particularly important in supporting cognition and attention, which were both perceived by patients to be improved via self-reported questionnaires of overall health and well-being.

The findings were published in the journal Frontiers in Neurology.