Emodin ameliorates renal injury in BXSB mice by modulating TNF-α/ICAM-1

The purpose of the present study was to explore the effects of emodin on renal injury in a BXSB mouse model of lupus and its mechanisms. BXSB mice were fed different concentrations of emodin (0, 5, 10 and 20 mg/kg.d), and the levels of intercellular adhesion molecule-1 (ICAM-1), tumor necrosis factor-α (TNF-α) and fibronectin (FN) levels in the glomeruli and serum levels of the anti-dsDNA antibody were determined. Mesangial cells (MCs) were cultured in vitro, and IgG-type anti-dsDNA antibody and/or emodin were added to the MC culture supernatant. In addition, TNF-α small interfering RNA (siRNA) was transfected into MCs to explore the mechanism of action of emodin. The results showed that the mice fed emodin presented decreases in the urinary protein content and glomerular TNF-α, ICAM-1 and FN levels (P<0.05). Moreover, the urine protein, TNF-α, ICAM-1 and FN levels were decreased in a dose-dependent manner (P<0.05). In vitro, the anti-dsDNA antibody group exhibited increased levels of ICAM-1 and TNF-α (P<0.05), and the anti-dsDNA antibody group showed myofibroblast-like structural changes. The aforementioned indexes were decreased in the emodin group (P<0.05), and the extent of transdifferentiation was significantly reduced. Moreover, the level of ICAM-1 decreased with the down-regulation of TNF-α (P<0.05). Emodin reduced the urine protein levels and serum levels of the anti-dsDNA antibody in a mouse model of lupus nephritis (LN). The underlying mechanism may be related to decreased levels of TNF-α, ICAM-1 and FN and the inhibition of dsDNA antibody-induced MC damage.