Most upcoming treatments today for Alzheimer's disease target the build-up of amyloid plaques and tau tangles in the brain. Emerging research, however, shows that homeostatic dysregulation of the brain's immune system, especially involving microglia, plays an essential role in both disease onset and progression. How to modulate microglia to treat Alzheimer's, however, has remained unclear.
Xenon gas is a noble gas that can cross the brain barrier. It is used as both an anesthetic and a neuroprotectant for brain injuries in human patients. In the current study, researchers investigated the effects of Xenon gas on micrologic and Alzheimer's pathology in mouse models of the condition.
To do so, they designed a custom Xenon gas inhalation chamber where they treated several mice with Alzheimer's. Inhaling the gas was found to reduce brain atrophy and neuroinflammation, and improve nest-building behaviors. It also increased a protective microglial response linked with clearing amyloid and improving cognition.
"It is exciting that in both animal models that model different aspects of Alzheimer's disease, amyloid pathology in one model and tau pathology in another model, that Xenon had protective effects in both situations," said senior and co-corresponding author of the study David M. Holtzman, MD, from Washington University School of Medicine in St. Louis, in a press release.
An early-phase clinical trial seeking to establish safety and dosage in healthy volunteers is due to begin in the next few months at Brigham and Women's Hospital. Meanwhile, the researchers intend to study the mechanisms by which Xenon gas modulates Alzheimer's alongside its potential for treating other conditions including multiple sclerosis and eye diseases that involve neuronal loss. They are additionally developing technologies to enable more efficient use of Xenon gas and to potentially recycle it.
"If the clinical trial goes well, the opportunities for the use of Xenon gas are great. It could open the door to new treatments for helping patients with neurologic diseases," said co-author of the study, Howard Weiner, MD, co-director of the Ann Romney Center for Neurologic Diseases at Brigham and Women's Hospital and principal investigator of the upcoming clinical trial, in a press release.
Sources: Science Daily, Science Translational Medicine
