Figure 3 Icariin restored mitochondrial homeostasis in UUO mice. (A) Representative immunofluorescence staining and quantitative of TOMM20 showed that icariin increased mitochondrial mass. (B) Representative transmission electron microscope images of mitochondria in renal tubular epithelial cells. (C) Quantification of the percentage of damaged mitochondria. * p < 0.05, ** p < 0.01.
Icariin inhibited profibrotic phenotype and inflammatory response in TGF-β1-exposed HK-2 cells
To further validate the protective role of icariin in tubulointerstitial fibrosis, TGF-β1-treated HK-2 cells were used to detect the effects of icariin in vitro . Firstly, we assessed the cytotoxic effect of icariin on HK-2 cells and observed that the cytotoxic concentration exceeded 200μM (Figure 4A). Based on published literatures and preliminary experiments, we determined that the effective concentration of icariin was 50µM. Then, we measured whether icariin (50µM) could inhibit profibrotic effects of TGF-β1 in HK-2 cells. Similar to the findings in the in vivo model, icariin dramatically inhibited profibrotic phenotype of TGF-β1-treated HK-2 cells, as demonstrated by the reduction of collagen I and α-SMA expression levels (Figure 4B). Additionally, quantitative real-time PCR of IL-1β, TNF-α and IL-6 demonstrated that icariin reduced the mRNA expression of inflammatory factors in HK-2 cells (Figure 4C-E). These results validated the anti-inflammatory and antifibrosis properties of icariin in vitro .