High-Salt Diet Induces Brain Inflammation Contributing to Resistant Hypertension

A groundbreaking study reveals that consuming a diet high in salt can trigger inflammation in the brain, which may be a key factor in the development of stubborn high blood pressure, or hypertension. Led by McGill University researcher Masha Prager-Khoutorsky, the research team collaborated with experts at McGill and the McGill University Health Center to investigate this novel connection.

Hypertension is a widespread condition affecting two-thirds of individuals over 60 and is responsible for over 10 million deaths each year worldwide. Often asymptomatic, it significantly increases the risk of heart disease, stroke, and other severe health issues. Traditionally, hypertension has been attributed mainly to issues with the kidneys and blood vessels, with most treatment strategies targeting these areas. However, about one-third of patients do not respond to standard medications, indicating other underlying causes.

The latest research, published in the journal Neuron, suggests that the brain itself plays a crucial role in regulating blood pressure, especially in cases resistant to typical therapies. The study involved giving rats water containing 2% salt—simulating high intake from processed foods like bacon, instant noodles, and cheese—to mimic human dietary patterns.

Using advanced imaging and lab techniques, researchers observed that a high-salt diet activated immune cells in specific brain regions, leading to inflammation. This inflammatory response caused an increase in vasopressin, a hormone known to elevate blood pressure. The findings highlight a previously underappreciated role of the brain in the mechanisms underlying hypertension.

"This evidence indicates that high blood pressure can originate within the brain itself, which opens new avenues for treatments that specifically target brain mechanisms," said Prager-Khoutorsky. She emphasized that since rats regulate salt and water more similarly to humans than mice do, these results are particularly relevant.

The researchers noted that studies involving rats, rather than mice, provide more accurate insights into human physiology concerning salt and water regulation.

Moving forward, the team plans to investigate whether similar inflammatory processes in the brain are involved in other forms of hypertension, potentially leading to novel therapeutic approaches for resistant cases.

This research underscores the importance of considering the brain as a significant factor in hypertension, beyond the traditional focus on blood vessels and kidneys. It also emphasizes the need for further studies to explore brain-targeted therapies in managing high blood pressure.

For more detailed insights, the full study is available in the journal Neuron: Ning Gu et al, "Microglia regulate neuronal activity via structural remodeling of astrocytes," 2025. — source: https://medicalxpress.com/news/2025-08-hight-salt-diet-brain-inflammation.html