Decreased glomerular filtration as the primary factor of elevated circulating suPAR levels in focal segmental glomerulosclerosis.
BACKGROUND
Circulating factor(s) has been thought to be the underlying cause of focal segmental glomerulosclerosis (FSGS), and recent studies foster this idea by demonstrating increased soluble urokinase receptor (suPAR) levels in the serum of FSGS patients.


METHODS
To explore the possible contribution of suPAR in FSGS pathogenesis, we analyzed serum suPAR levels in 17 patients with FSGS and compared them with those in patients with steroid-sensitive nephrotic syndrome, chronic glomerulonephritis, or non-glomerular kidney diseases.


RESULTS
Serum suPAR levels in patients with FSGS were higher than those in patients with steroid-sensitive nephrotic syndrome or chronic glomerulonephritis, but not higher than those in patients with non-glomerular kidney diseases. suPAR levels negatively correlate with estimated glomerular filtration rate and were decreased after renal transplantation in patients with FSGS as well as in those with non-glomerular kidney diseases. Furthermore, 6 FSGS patients with post-transplant recurrence demonstrated that suPAR levels were not high during the recurrence.


CONCLUSIONS
Based on our results, elevated suPAR levels in FSGS patients were attributed mainly to decreased glomerular filtration. These data warrant further analysis for involvement of possible circulating factor(s) in FSGS pathogenesis.
Department of Pediatrics, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan, haritay-ped@h.u-tokyo.ac.jp.
Yutaka
Y
Harita
Kiyonobu
K
Ishizuka
Atsushi
A
Tanego
Noriko
N
Sugawara
Hiroko
H
Chikamoto
Yuko
Y
Akioka
Haruko
H
Tsurumi
Kenichiro
K
Miura
Yoshimitsu
Y
Gotoh
Makoto
M
Tsujita
Takayuki
T
Yamamoto
Keiji
K
Horike
Asami
A
Takeda
Akira
A
Oka
Takashi
T
Igarashi
Motoshi
M
Hattori
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology*; D005923:Glomerulosclerosis, Focal Segmental / Q000097:blood*; D006801:Humans; D016030:Kidney Transplantation; D008297:Male; D055293:Receptors, Urokinase Plasminogen Activator / Q000097:blood*
D055293:Receptors, Urokinase Plasminogen Activator