Fig. 4

HDL functionality. (Panel a) Cholesterol efflux: HDL was isolated from subjects with DKD and controls and utilized as an acceptor of cellular cholesterol. Bone marrow-derived macrophages (BMDMs) overloaded with acetylated LDL and ¹⁴C-cholesterol were incubated with 50 μg of HDL/mL of medium for 6 h. Cholesterol efflux was determined after measuring the radioactivity in the culture medium and that remaining in cells, which was calculated as ¹⁴C-cholesterol in the medium/¹⁴C-cholesterol in the medium +¹⁴C-cholesterol in cells × 100. Control incubations were performed in the presence of DMEM/FAFA in the absence of HDL, and the results were subtracted from those obtained in the presence of HDL. (Panels b and c) Antioxidant activity: The lag time (panel b) and the maximum rate of LDL oxidation (panel c) were determined in incubations with LDL (40 μg of protein) isolated from a healthy donor with CuSO₄ solution and HDL from DKD or controls (80 μg of protein). (Panels d and e) Anti-inflammatory activity: BMDMs overloaded with acetylated LDL (50 μg/mL) were treated with HDL (50 μg/mL) for 24 h. After washing, cells were treated with LPS (1 μg/mL) for 24 h, and interleukin-6 (IL-6, panel d) and TNF-alpha (panel e) levels in the medium were determined by ELISA. The results were compared by the Kruskal-Wallis test with the Holm-Sidak posttest or Student’s t test