Affiliations: Department of Medicine and Therapeutics, The Chinese
University of Hong Kong, Shatin, Hong Kong, China | Department of Anatomical and Cellular Pathology,
Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong
Kong, China | Division of Nephrology, Renmin Hospital of Wuhan
University, China
Note: [] Corresponding author: Dr. C.-C. Szeto, Department of Medicine
and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong
Kong, Shatin, NT, Hong Kong, China. Tel.: +86 852 2632 3126; Fax: +86 852 2637
3852; E-mail: ccszeto@cuhk.edu.hk
Abstract: Background: Previous studies suggested miR-146a and miR-155 play
important roles in innate and adaptive immune responses. We studied intra-renal
and urinary levels of miR-146a and miR-155 in patients with immunoglobulin A
nephropathy (IgAN). Methods: Intra-renal and urinary levels of miR-146a
and miR-155 are quantified in 43 patients with IgAN; the result was compared to
20 nephrectomy specimens and urine sediment of 13 healthy volunteers. Results: The levels of intra-renal and urinary levels of miR-146a and miR-155
of IgAN are significantly higher than controls. Estimated glomerular filtration
rate inversely correlates with intra-renal level of miR-146a and miR-155;
proteinuria positively correlates with intra-renal level of miR-146a and
miR-155, as well as urinary level of miR-146a and miR-155. Intra-renal level of
miR-155 significantly correlates with tubulointerstitial scarring. Urinary
level of miR-146a inversely correlates with urinary expression of interleukin
(IL)-1β, IL-6 and tumor necrosis factor (TNF)-α and positively
correlates with urinary expression of regulated upon activation, normal T-cell
expressed, and secreted (RANTES). Urinary level of miR-155 inversely correlates
with urinary expression of IL-1β and TNF-α and positively
correlates with urinary expression of forkhead box P3 (FOXP3) and RANTES. Conclusion: We conclude that intra-renal and urinary levels of miR-146a and
miR-155 were significantly elevated in IgAN, and the degree of upregulation
correlates with clinical and histological severity of the disease. Our results
suggested miR-146a and miR-155 might play an important role in the
pathophysiology of IgAN.
