Interleukin-17A regulates renal sodium transporters and renal injury in angiotensin II–induced hypertension

AE Norlander, MA Saleh, NV Kamat, B Ko, J Gnecco… - …, 2016 - Am Heart Assoc
AE Norlander, MA Saleh, NV Kamat, B Ko, J Gnecco, L Zhu, BL Dale, Y Iwakura, RS Hoover…
Hypertension, 2016Am Heart Assoc
Angiotensin II–induced hypertension is associated with an increase in T-cell production of
interleukin-17A (IL-17A). Recently, we reported that IL-17A−/− mice exhibit blunted
hypertension, preserved natriuresis in response to a saline challenge, and decreased renal
sodium hydrogen exchanger 3 expression after 2 weeks of angiotensin II infusion compared
with wild-type mice. In the current study, we performed renal transporter profiling in mice
deficient in IL-17A or the related isoform, IL-17F, after 4 weeks of Ang II infusion, the time …
Angiotensin II–induced hypertension is associated with an increase in T-cell production of interleukin-17A (IL-17A). Recently, we reported that IL-17A−/− mice exhibit blunted hypertension, preserved natriuresis in response to a saline challenge, and decreased renal sodium hydrogen exchanger 3 expression after 2 weeks of angiotensin II infusion compared with wild-type mice. In the current study, we performed renal transporter profiling in mice deficient in IL-17A or the related isoform, IL-17F, after 4 weeks of Ang II infusion, the time when the blood pressure reduction in IL-17A−/− mice is most prominent. Deficiency of IL-17A abolished the activation of distal tubule transporters, specifically the sodium–chloride cotransporter and the epithelial sodium channel and protected mice from glomerular and tubular injury. In human proximal tubule (HK-2) cells, IL-17A increased sodium hydrogen exchanger 3 expression through a serum and glucocorticoid-regulated kinase 1–dependent pathway. In mouse distal convoluted tubule cells, IL-17A increased sodium–chloride cotransporter activity in a serum and glucocorticoid-regulated kinase 1/Nedd4-2–dependent pathway. In both cell types, acute treatment with IL-17A induced phosphorylation of serum and glucocorticoid-regulated kinase 1 at serine 78, and treatment with a serum and glucocorticoid-regulated kinase 1 inhibitor blocked the effects of IL-17A on sodium hydrogen exchanger 3 and sodium–chloride cotransporter. Interestingly, both HK-2 and mouse distal convoluted tubule 15 cells produce endogenous IL-17A. IL17F had little or no effect on blood pressure or renal sodium transporter abundance. These studies provide a mechanistic link by which IL-17A modulates renal sodium transport and suggest that IL-17A inhibition may improve renal function in hypertension and other autoimmune disorders.
Am Heart Assoc