The effects of inflammation on lipid accumulation in the kidneys of children with primary nephrotic syndrome

Abstract

This study aimed to characterize the relationship between inflammation and lipid accumulation in children with primary nephrotic syndrome (PNS). Local expression of interleukin-1β (IL-1β), transforming growth factor-β1 (TGF-β1), low-density lipoprotein receptor (LDLr), sterol regulatory element binding protein-2 (SREBP-2), SREBP cleavage-activating protein (SCAP), and apolipoprotein B100 (apoB100) was analyzed by immunohistochemistry in kidney tissues obtained from children with PNS. Renal histopathology was evaluated by hematoxylin and eosin and periodic acid-Schiff staining. Serum levels of IL-1β and TGF-β1 were measured by enzyme-linked immunosorbent assays. Expression of IL-1β, TGF-β1, LDLr, SREBP-2, SCAP, and apoB100 was higher in samples from patients with non-minimal change necrotic syndrome (NMCNS) compared to both controls and patients with minimal change necrotic syndrome. Deposition of apoB100 was significantly correlated with expression of IL-1β, TGF-β1, LDLr, SREBP-2, and SCAP and with the glomerulosclerosis index, but not with plasma lipid levels. Expression of IL-1β and TGF-β1 was significantly correlated with expression of LDLr, SREBP-2, and SCAP. These findings suggest that inflammation leads to lipid accumulation in the kidney through disruption of the expression of proteins in the SCAP/SREBP-2/LDLr signaling pathway, which may underlie glomerulosclerosis and tubulointerstitial fibrosis in NMCNS.