Hyperbaric oxygen therapy ameliorates pathophysiology of 3xTg-AD mouse model by attenuating neuroinflammation

There is a real need for new interventions for Alzheimer's disease (AD). Hyperbaric oxygen therapy (HBOT), the medical administration of 100% oxygen at conditions greater than 1 atmosphere absolute, has been used successfully to treat several neurological conditions, but its effects on AD pathology have never been thoroughly examined. Therefore, we exposed old triple-transgenic (3xTg) and non-transgenic mice to HBOT followed by behavioral, histological, and biochemical analyses. HBOT attenuated neuroinflammatory processes by reducing astrogliosis, microgliosis, and the secretion of proinflammatory cytokines (IL-1β and TNFα) and increasing expression of scavenger receptor A, arginase1, and antiinflammatory cytokines (IL-4 and IL-10). Moreover, HBOT reduced hypoxia, amyloid burden, and tau phosphorylation in 3xTg mice and ameliorated their behavioral deficits. Therefore, we suggest that HBOT has multifaceted effects that reduce AD pathologies, even in old mice. Given that HBOT is used in the clinic to treat various indications, including neurological conditions, these results suggest HBOT as a novel therapeutic intervention for AD.