Excessive Iron in Diets Promotes Kidney Fibrosis via Disordering the Inflammation Factors in Sheep

Abstract

Iron is a mineral that the body acquires from the environment in order to maintain physiological function; however, excessive iron causes disease. The aim of this work is to investigate the processes by which excessive iron in diets induces kidney fibrosis in sheep by disorders their inflammatory factors. All sheep were fed a basal diet supplemented with 50 (CON), 500 (L-iron), 1000 (M-iron), and 1500 (H-iron) mg Fe/kg as ferrous sulfate monohydrate (FeSO4·H2O), respectively. Hematoxylin-Eosin (H&E), Perls, and Masson staining were used to observe histopatholological alterations; Western blotting, ELISA, and quantitative real-time polymerase chain reaction (qRT-PCR) were used to detect changes in the amounts of key inflammatory factor genes and proteins. As iron intake rose, glomerular cell contents dropped, tubular inflammatory cells infiltrated and fibrin was secreted, collagen fiber deposition and fibrosis have noticeable symptoms. Interleukin-1β (IL-1β), tumour necrosis factor-α (TNF-α), and interferon-γ (IFN-γ) activities were decreased, while interleukin-2 (IL-2), interleukin-6 (IL-6), nuclear factor-κB (NF-κB), and transforming growth factor-β1 (TGF-β1) actvities were increased. Excessive iron disorders inflammatory factor secretion, triggers an inflammatory response, and promotes the development of renal fibrosis, according to this study.