Obstructive Sleep Apnea-Induced Hypertension Is Associated With Increased Gut and Neuroinflammation

Area of Science:

• Immunology
• Gastroenterology
• Cardiovascular Science

Background:

• Obstructive sleep apnea (OSA) is a known risk factor for hypertension.
• OSA is linked to gut dysbiosis, which contributes to elevated blood pressure.
• The precise mechanisms connecting gut dysbiosis to hypertension are not fully understood.

Purpose of the Study:

• To investigate the hypothesis that OSA-induced gut inflammation contributes to neuroinflammation and hypertension.
• To explore the role of specific immune cells and signaling pathways in this process.

Main Methods:

• Obstructive sleep apnea (OSA) was induced in male rats.
• Lymphocyte populations were analyzed in various tissues (aorta, brain, gut, lymphoid organs) using flow cytometry.
• The effect of neutralizing interleukin-17a (IL-17a) on immune cells and blood pressure was assessed.
• Gut-derived lymphocytes were tracked for migration patterns.

Main Results:

• OSA rats exhibited decreased T regulatory cells and increased T helper 17 (T_H17) cells in the gut and brain.
• Neutralization of IL-17a significantly lowered blood pressure and modulated T cell populations in OSA rats.
• Gut-derived T cells (T_H1, T_H2, T_H17) showed increased migration to the brain in OSA rats.

Conclusions:

• OSA triggers a pro-inflammatory response in the gut and brain mediated by IL-17a signaling.
• Gut dysbiosis may initiate inflammation in both the gut and the brain.
• Targeting gut dysbiosis could be a therapeutic strategy for reducing neuroinflammation and hypertension associated with OSA.