Histologic and morphologic analysis was performed as previously described [19 (link)]. Histochemical staining was performed with hematoxylin/eosin and sirius red. Immunohistochemical staining was performed using primary antibodies against p-Smad3 (1:500; Santa Cruz Biotechnology, Santa Cruz, CA, USA), α-SMA (1:500; Sigma, St. Louis, MO, USA), PAI-1 (1:500; BD Biosciences, San Jose, CA, USA), and type 1 collagen (1:500; Abcam, Cambridge, UK), followed by horseradish peroxidase-conjugated anti-mouse or anti-rabbit immunoglobulin G secondary antibodies (Dako, Glostrup, Denmark). Quantification of renal fibrosis was measured as previously described [19 (link)].