Fig. 4.

Exosomes from high glucose-treated renal tubular cells activate fibroblasts. High glucose-treated tubular cell exosomes (HG-Exo) or normal glucose-treated tubular cell exosomes (NG-Exo) were added to NRK-49F cells. A: representative images of phase contrast showing the cellular morphology of fibroblasts (n = 4). Scale bars = 100 and 200 μm. B: total cell numbers of NRK-49F fibroblasts. Data are expressed as means ± SD. *P < 0.05, significantly different from the control (Ctrl) group. C: total protein levels of NRK-49F fibroblasts. Data are expressed as means ± SD; n = 4. *P < 0.05, significantly different from the Ctrl group; **P < 0.01 vs. the NG-Exo group. D: representative images of immunoblot analysis of fibronectin, collagen type I, and α-smooth muscle actin (α-SMA). Cyclophilin B was used as a loading control (n = 4). E: densitometric analysis of fibronectin, collagen type I, and α-SMA signals. After being normalized with cyclophilin B, the protein signal of control was arbitrarily set as 1, and the signals of other conditions were normalized with controls to calculate fold changes. Data are expressed as means ± SD; n = 4. *P < 0.05 vs. the Ctrl group; #P < 0.05 vs. the NG-Exo group.