Fig. 1.

MicroRNA 21 is upregulated in injury with fibrosis in mouse and human kidney. (A-B) Plots showing significantly upregulated microRNAs [red box, P < 0.001] detected on Agilent microRNA microarrays (A) after d10 of murine kidney UUO compared to normal kidney and (B) after 10d of murine unilateral kidney IRI compared with normal kidney. (C) Time course Q-PCR of whole kidney total RNA for miR-21 normalized to Sno234, from mice with UUO or IRI [** P < 0.01, * P< 0.05]. (D) RT-qPCR for miR-21 normalized to RNU19 in human kidney biopsies from patients with kidney transplantation (n= 5/group). Biopsies from healthy donor kidneys were normal or patients with CAD or transplant AKI was determined by histological assessment. (E) Q-PCR for miR-21 normalized to Sno234 from total RNA of purified endothelial cells, pericyte/myofibroblasts, macrophages and proximal epithelial cells from normal mouse kidney or d2 or d7 of UUO kidney. (F) Comparative Q-PCR from purified cells from normal kidney. (G) In situ hybridization of normal or post IRI murine kidney sections from miR-21^+/+ or miR-21^-/- mice for miR-21. Purple stain shows the presence of miR-21. Note in normal kidney some epithelium in medulla and papilla and some perivascular cells have miR-21 but in post IRI kidney expression of miR-21 is widespread in the kidney. [v = venule, a = arteriole, g = glomerulus, bar = 50μm] (n = 3-7/group. * P<0.05, **P<0.01).