title: Elevated urinary podocyte-derived extracellular microvesicles in renovascular hypertensive patients.
abstract: BACKGROUND
  An increased number of podocyte-derived extracellular vesicles (pEVs) may reflect podocyte injury in renal disease. Elevated glomerular pressure and other insults may injure podocytes, yet it remains unclear whether the numbers of pEVs are altered in hypertensive patients. We tested the hypothesis that urinary pEV levels would be elevated in patients with renovascular hypertension (RVH) compared with essential hypertension (EH) or healthy volunteers (HVs).
  
  
  METHODS
  We prospectively enrolled patients with EH ( n = 30) or RVH ( n = 31) to study renal blood flow (RBF) and cortical perfusion using multidetector computed tomography under controlled condition (regulated sodium intake and renin-angiotensin blockade). After isolation from urine samples, pEVs (nephrin and podocalyxin positive) were characterized by flow cytometry. Fourteen RVH patients were studied again 3 months after stenting or continued medical therapy. HVs ( n = 15) served as controls.
  
  
  RESULTS
  The fraction of pEV among urinary EVs was elevated in RVH compared with HVs and EH (11.4 ± 6.4, 6.8 ± 3.4 and 6.3 ± 3.7%, respectively; P < 0.001) and remained unchanged after 3 additional months of therapy and after controlling for clinical parameters. However, eGFR- and age-adjusted pEV levels did not correlate with any clinical or renal parameters.
  
  
  CONCLUSIONS
  In hypertensive patients under controlled conditions, urinary pEV levels are elevated in patients with RVH and low eGFR compared with patients with EH and relatively preserved renal function. These pEVs may reflect podocyte injury secondary to kidney damage, and their levels might represent a novel therapeutic target.
authors.affiliation: Division of Nephrology and Hypertension, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.|Division of Nephrology, Soonchunhyang University Hospital, Seoul, Korea.
authors.forename: Soon Hyo
authors.initials: SH
authors.lastname: Kwon
authors.affiliation: Division of Nephrology and Hypertension, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
authors.forename: John R
authors.initials: JR
authors.lastname: Woollard
authors.affiliation: Division of Nephrology and Hypertension, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Saad
authors.affiliation: Division of Nephrology and Hypertension, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
authors.forename: Vesna D
authors.initials: VD
authors.lastname: Garovic
authors.affiliation: Division of Nephrology and Hypertension, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
authors.forename: Ladan
authors.initials: L
authors.lastname: Zand
authors.affiliation: Division of Nephrology and Hypertension, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
authors.forename: Kyra L
authors.initials: KL
authors.lastname: Jordan
authors.affiliation: Division of Nephrology and Hypertension, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Textor
authors.affiliation: Division of Nephrology and Hypertension, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
authors.forename: Lilach O
authors.initials: LO
authors.lastname: Lerman
mesh_terms: D000368:Aged; D055252:Cell-Derived Microparticles / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D006978:Hypertension, Renovascular / Q000473:pathology* / Q000652:urine*; D008297:Male; D008875:Middle Aged; D050199:Podocytes / Q000378:metabolism / Q000473:pathology*; D011446:Prospective Studies; D012079:Renal Circulation
keywords: CKD; extracellular vesicles; hypertension; podocyte; renovascular hypertension