Human Tissue Kallikrein 1 Improves Erectile Dysfunction of Streptozotocin-Induced Diabetic Rats by Inhibition of Excessive Oxidative Stress and Activation of the PI3K/AKT/eNOS Pathway

Figure 8

hKLK1 inhibited oxidative stress, cell apoptosis, and cGMP production in CSMC under high-glucose condition. Panels (a), (b), and (c) show protein expressions of RAGE, NOX2, Bax, and Bcl-2 level normalized to β-actin and Bax/Bcl-2 ratio in CSMC under normal and high-glucose culture conditions. Panels (d) to (f) show the ROS production and percentage of apoptotic CSMC under different glucose concentrations and incubation times by fluorescence and flow cytometry in WTR and TGR with or without HOE140. All images were captured at magnification of 200x. Panel (g) shows cGMP level under normal and high-glucose culture conditions. Each bar represents . , , and . hKLK1: human tissue kallikrein 1; ROS: reactive oxygen species. WTR: wild-type rats; TGR: transgenic rats; LMWK: low-molecular-weight kininogen; BK: bradykinin; PI3K: phosphatidylinositol 3-kinase; AKT: protein kinase B; eNOS: endothelial nitric oxide synthase; NO: nitric oxide; cGMP: cyclic guanosine monophosphate; GTP: guanosine triphosphate; GC: guanylate cyclase; EC: endothelial cell; CSMC: cavernous smooth muscle cell.

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