Format

Send to

Choose Destination
JCI Insight. 2019 Jun 4;5. pii: 126241. doi: 10.1172/jci.insight.126241.

High dietary salt-induced dendritic cell activation underlies microbial dysbiosis-associated hypertension.

Author information

1
Division of Cardiovascular Medicine, Department of Medicine.
2
Vanderbilt Translational and Clinical Cardiovascular Research Center.
3
Division of Clinical Pharmacology, Department of Medicine, and.
4
Division of Comparative Medicine, Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
5
Department of Biostatistics and.
6
Vanderbilt Technologies for Advanced Genomics core facility, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
7
Department of Biostatistics and Medical Informatics, University of Wisconsin-Madison, Madison, Wisconsin.
8
Cardiology Division, Department of Medicine, Columbia University Medical Center, New York, New York, USA.
9
Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA.

Abstract

Excess dietary salt contributes to inflammation and hypertension via poorly understood mechanisms. Antigen presenting cells including dendritic cells (DCs) play a key role in regulating intestinal immune homeostasis in part by surveying the gut epithelial surface for pathogens. Previously, we found that highly reactive γ-ketoaldehydes or isolevuglandins (IsoLGs) accumulate in DCs and act as neoantigens, promoting an autoimmune-like state and hypertension. We hypothesized that excess dietary salt alters the gut microbiome leading to hypertension and this is associated with increased immunogenic IsoLG-adduct formation in myeloid antigen presenting cells. To test this hypothesis, we performed fecal microbiome analysis and measured blood pressure of healthy human volunteers with salt intake above or below the American Heart Association recommendations. We also performed 16S rRNA analysis on cecal samples of mice fed normal or high salt diets. In humans and mice, high salt intake was associated with changes in the gut microbiome reflecting an increase in Firmicutes, Proteobacteria and genus Prevotella bacteria. These alterations were associated with higher blood pressure in humans and predisposed mice to vascular inflammation and hypertension in response to a sub-pressor dose of angiotensin II. Mice fed a high salt diet exhibited increased intestinal inflammation including the mesenteric arterial arcade and aorta, with a marked increase in the B7 ligand CD86 and formation of IsoLG-protein adducts in CD11c+ myeloid cells. Adoptive transfer of fecal material from conventionally housed high salt-fed mice to germ-free mice predisposed them to increased intestinal inflammation and hypertension. These findings provide novel insight into the mechanisms underlying inflammation and hypertension associated with excess dietary salt and may lead to interventions targeting the microbiome to prevent and treat this important disease.

KEYWORDS:

Hypertension; Inflammation

Supplemental Content

Full text links

Icon for American Society for Clinical Investigation Icon for PubMed Central
Loading ...
Support Center