Hypoxic-hyperoxic conditioning and dementia

Intermittent hypoxia conditioning (IHC) and intermittent hypoxia-hyperoxia conditioning (IHHC) could potentially moderate the development and progression of dementia/Alzheimer’s. IHC was shown in animal and human studies to improve cardiovascular risk factors, augment cerebral blood flow and endothelial nitric oxide production, decrease oxidative stress, prevent neuronal degeneration, and stimulate neurogenesis and neuroregeneration. Recent studies suggest that IHHC may be superior to IHC in improving brain function. Herein, the application of this emerging intervention to improve cognitive function in dementia, and the still incomplete understanding of IHHC’s mechanisms, are presented. One might speculate that the combination of hypoxic and hyperoxic intervals on one hand could synergistically improve antioxidant defenses, redox signaling, and cerebral blood flow, and on the other hand, might activate complementary neuroprotective pathways. Although initial studies in animal models and patients show IHHC to be a promising therapy to preserve neurocognitive function in dementia, further work is essential to delineate IHHC’s molecular underpinnings and elucidate its key differences versus IHC.