Background: Inflammation plays an important role in polycystic kidney disease (PKD). The current study aimed to examine the efficacy of the anti-inflammatory compound resveratrol in PKD and to investigate its underlying mechanism of action.
Methods: Male Han:SPRD (Cy/+) rats with PKD were treated with 200 mg/kg/day resveratrol or vehicle by gavage for 5 weeks. Human autosomal dominant (AD) PKD cells, three-dimensional (3D) Madin-Darby canine kidney cells and zebrafish were treated with various concentrations of resveratrol or the nuclear factor κB (NF-κB) inhibitor QNZ.
Results: Resveratrol treatment reduced blood urea nitrogen levels and creatinine levels by 20 and 24%, respectively, and decreased two-kidney/total body weight ratio by 15% and cyst volume density by 24% in Cy/+ rats. The proliferation index and the macrophage infiltration index were reduced by 40 and 43%, respectively, in resveratrol-treated cystic kidneys. Resveratrol reduced the levels of the pro-inflammatory factors monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-α (TNF-α) and complement factor B (CFB) in Cy/+ rat kidneys in parallel with the decreased activity of NF-κB (p50/p65). The activation of NF-κB and its correlation with pro-inflammatory factor expression were confirmed in human ADPKD cells and kidney tissues. Resveratrol and QNZ inhibited the expression of MCP-1, TNF-α and CFB and reduced NF-κB activity in ADPKD cells. Moreover, NF-κB blockage minimized the inhibition of inflammatory factor production by resveratrol treatment. Furthermore, resveratrol or QNZ inhibited cyst formation in the 3D cyst and zebrafish models.
Conclusions: The NF-κB signaling pathway is activated and partly responsible for inflammation in polycystic kidney tissues. Targeting inflammation through resveratrol could be a new strategy for PKD treatment in the future.
Keywords: NF-κB; autosomal dominant polycystic kidney disease; inflammation; mTOR; macrophages.
© The Author 2016. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.