ET-3/ETBR Mediates Na-Activated Immune Signaling and Kidney Lymphatic Dynamics.

Background: Lymphatic collecting vessels in the kidney are critical in clearing interstitial fluid, macromolecules, and infiltrating immune cells. Dysfunction of the lymphatic vessels can disrupt this process and exacerbate injury-associated inflammation in many disease conditions. We previously found that sodium accumulates within the kidney interstitium during proteinuric kidney injury and elevated sodium environments stimulate isolevuglandin production in antigen-presenting cells, stimulating T cells, and modulating inflammatory responses.

Myeloid Cell Glucocorticoid, Not Mineralocorticoid Receptor Signaling, Contributes to Salt-Sensitive Hypertension in Humans via Cortisol.

Background: Salt sensitivity of blood pressure (SSBP) is an independent risk factor for cardiovascular morbidity and mortality, yet the etiology is poorly understood. We previously found that serum/glucocorticoid-regulated kinase 1 (SGK1) and epoxyeicosatrienoic acids (EETs) regulate epithelial sodium channel (ENaC)-dependent sodium entry into monocyte-derived antigen-presenting cells (APCs) and activation of NADPH oxidase, leading to the formation of isolevuglandins (IsoLGs) in SSBP. Whereas aldosterone via the mineralocorticoid receptor (MR) activates SGK1 leading to hypertension, our past findings indicate that levels of plasma aldosterone do not correlate with SSBP, and there is little to no MR expression in APCs.

Murine Fecal Isolation and Microbiota Transplantation.

Gut microbiota dysbiosis plays a role in the pathophysiology of cardiovascular and metabolic disorders, but the mechanisms are not well understood. Fecal microbiota transplantation (FMT) is a valuable approach to delineating a direct role of the total microbiota or isolated species in disease pathophysiology. It is a safe treatment option for patients with recurrent Clostridium difficile infection.

Intestinal Lymphatic Dysfunction in Kidney Disease.

Kidney disease is associated with adverse consequences in many organs beyond the kidney, including the heart, lungs, brain, and intestines. The kidney-intestinal cross talk involves intestinal epithelial damage, dysbiosis, and generation of uremic toxins. Recent studies reveal that kidney injury expands the intestinal lymphatics, increases lymphatic flow, and alters the composition of mesenteric lymph.