High-Salt Diets, Intestinal Barrier, and Hypertension: A Mechanistic Review and the Promise of Dietary Therapy

Hypertension is a major public health problem worldwide, and high-salt diets are one of the main causes of hypertension. The intestinal mucosal immune system is the largest immune organ in vertebrates. Hypertension was associated with increased intestinal permeability and an inflammatory state. The bacterial communities attached to the intestinal mucosa played a significant role in the development and maturation of the autoimmune system, as well as inflammation and immunity to disease. In this review, we focused on the relationship between the impaired intestinal barrier and the development and progression of hypertension under the high-salt dietary pattern. We systematically reviewed how a high-salt diet caused hypertension by disrupting the intestinal mechanical, chemical, and microbial barriers, interacting with immunogenic isolevuglandin (IsoLG)-protein adducts and microbiota, and activating the mitogen-activated protein kinase (MAPK)/nuclear factor-kappa B (NF-κB) signaling pathway. Meanwhile, this review also summarizes the dietary therapy for hypertension, which involves supplementing natural antihypertensive substances and adjusting dietary patterns to repair the intestinal barrier and assist in lowering blood pressure. Such measures included supplementing plant-based foods, polyunsaturated fatty acids (PFAs), probiotics, prebiotics, food-medicine homologous substances (FMHS), vitamins, and minerals, as well as transforming high-salt dietary patterns into the dietary approaches to stop hypertension (DASH), the Mediterranean diet (MD), and the ketogenic diet (KD), with the aim of providing a reference for the occurrence, development, and dietary prevention and control of high-salt hypertension.