New Association Between Hypertension-Induced Dementia and Salt-Responsive Immune Cells Surrounding the Brain

December 05, 2023

A National Institutes of Health-supported study reveals that immune cell responses within the brain's protective covering may contribute to cognitive decline in individuals with chronic high blood pressure. 

Published in Nature Neuroscience and funded by the National Institute of Neurological Disorders and Stroke (NINDS), a division of NIH, this insight could offer novel strategies to counteract high blood pressure's cognitive effects. Roderick Corriveau, Ph.D., program director at NINDS, emphasizes the critical importance of understanding immune signaling's role in cognitive decline, providing valuable insights into potential dementia diagnoses resulting from immune system signaling.

Hypertension, affecting over 1 billion people globally, poses risks to cognitive function, even without a stroke occurrence. Attempts to mitigate cognitive loss in non-stroke individuals through blood pressure-lowering treatments have yielded mixed results. 

In a mouse model of high blood pressure, led by Costantino Iadecola, M.D., the study identifies abnormal immune cell activation around and within the brain under conditions mimicking common hypertension. The research highlights increased levels of interleukin-17 (IL-17), a chemical activating the immune system, in the cerebral spinal fluid and brain. This extends previous findings showing IL-17 elevation linked to cognitive impairment in response to a high-salt diet, emphasizing the impact of IL-17 within the brain. Importantly, the study employs a mouse model, the DOCA salt model, more closely resembling common hypertension in humans.