PF attenuates HG-induced filtration barrier damage. (A) Effects of various concentrations of PF on HG-induced permeability of GEnCs to FITC-dextran. (B) Expression levels of Sdc-1 in the cell culture supernatant. (C) Representative images of glycocalyx stained with FITC-WGA. (D) Quantification analysis of FITC-WGA staining. (E) Western blot analysis of Hpa-1, occludin-1, ZO-1, p-AMPK and total AMPK. Densitometry analysis of (F) Hpa-1, (G) occludin-1, (H) ZO-1 and (I) the p-AMPK/AMPK ratio. Data are presented as the mean ± standard deviation of three repeats. *P<0.05, **P<0.01, ***P<0.001 vs. control group; #P<0.05, ##P<0.01, ###P<0.001 vs. HG group. PF, piperazine ferulate; HG, high glucose; GEnCs, glomerular endothelial cells; FITC, fluorescein isothiocyanate; WGA, wheat germ agglutinin; Hpa-1, heparanase-1; ZO-1, Zonula occludens-1; p-, phosphorylated-; AMPK, adenosine monophosphate-activated protein kinase.