NaCl cotransporter abundance in urinary vesicles is increased by calcineurin inhibitors and predicts thiazide sensitivity

PLoS One. 2017 Apr 21;12(4):e0176220. doi: 10.1371/journal.pone.0176220. eCollection 2017.


Animal studies have shown that the calcineurin inhibitors (CNIs) cyclosporine and tacrolimus can activate the thiazide-sensitive NaCl cotransporter (NCC). A common side effect of CNIs is hypertension. Renal salt transporters such as NCC are excreted in urinary extracellular vesicles (uEVs) after internalization into multivesicular bodies. Human studies indicate that CNIs also increase NCC abundance in uEVs, but results are conflicting and no relationship with NCC function has been shown. Therefore, we investigated the effects of CsA and Tac on the abundance of both total NCC (tNCC) and phosphorylated NCC at Thr60 phosphorylation site (pNCC) in uEVs, and assessed whether NCC abundance in uEVs predicts the blood pressure response to thiazide diuretics. Our results show that in kidney transplant recipients treated with cyclosporine (n = 9) or tacrolimus (n = 23), the abundance of both tNCC and pNCC in uEVs is 4-5 fold higher than in CNI-free kidney transplant recipients (n = 13) or healthy volunteers (n = 6). In hypertensive kidney transplant recipients, higher abundances of tNCC and pNCC prior to treatment with thiazides predicted the blood pressure response to thiazides. During thiazide treatment, the abundance of pNCC in uEVs increased in responders (n = 10), but markedly decreased in non-responders (n = 8). Thus, our results show that CNIs increase the abundance of both tNCC and pNCC in uEVs, and these increases correlate with the blood pressure response to thiazides. This implies that assessment of NCC in uEVs could represent an alternate method to guide anti-hypertensive therapy in kidney transplant recipients.

MeSH terms

  • Animals
  • Calcineurin Inhibitors / pharmacology*
  • Case-Control Studies
  • Cohort Studies
  • Humans
  • Mice
  • Mice, Inbred C57BL
  • Sodium Chloride Symporters / metabolism*
  • Thiazides / pharmacology*


  • Calcineurin Inhibitors
  • Sodium Chloride Symporters
  • Thiazides

Grants and funding

This study was supported by Dutch Kidney Foundation (PHD12.14 and 16OI04) and EURenOmics funding from European Union seventh Framework Program (FP7/2007–2013, agreement no 305608). M.A.V. was funded by Consejo-Nacional de Ciencia-y-Tecnología (CONACYT-México) and “Doctores-Jóvenes” program, Universidad Autónoma de Sinaloa in Mexico. E.J.H. was supported by grants from Netherlands Organisation for Scientific Research (NWO, Veni 916.12.140) and Dutch Kidney Foundation (KSP-14OK19). R.A.F. was supported by Danish Medical Research Foundation, Lundbeck Foundation and Novo Nordisk Foundation. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.