Vascular Dysfunction, Oxidative Stress, and Inflammation in Autosomal Dominant Polycystic Kidney Disease

Background and objectives Both increased arterial stiffness and vascular endothelial dysfunction are evident in patients with autosomal dominant polycystic kidney disease, even early in the course of the disease when kidney function in preserved. Vascular dysfunction in autosomal dominant polycystic kidney disease is thought to be related to vascular oxidative stress and inflammation, but direct evidence is lacking. Design, setting, participants, & measurements We assessed carotid-femoral pulse-wave velocity (arterial stiffness) and brachial artery flow-mediated dilation (vascular endothelial function) in participants with early-stage autosomal dominant polycystic kidney disease (eGFR >= 60 ml/min per 1.73 m(2)) and a history of controlled hypertension and in healthy controls. Brachial artery flow-mediated dilation was also assessed after infusion of ascorbic acid to inhibit vascular oxidative stress compared with saline. Vascular endothelial cells were collected from a peripheral vein to measure expression of proteins, and circulating markers were also assessed by ELISA or liquid chromatography-tandem mass spectrometry. Results In total, 61 participants with autosomal dominant polycystic kidney disease (34 +/- 9 years old [mean +/- SD]) and 19 healthy controls (30 +/- 5 years old) were studied. Carotid-femoral pulse-wave velocity was higher in participants with autosomal dominant polycystic kidney disease compared with healthy controls (650 +/- 131 versus 562 +/- 81 cm/s; P=0.007). Brachial artery flow-mediated dilation was 8.2%+/- 5.8% in participants with autosomal dominant polycystic kidney disease and 10.8%+/- 4.7% in controls (P=0.08). Among participants with autosomal dominant polycystic kidney disease, flow-mediated dilation increased from 7.7%+/- 4.5% to 9.4%+/- 5.2% with ascorbic acid, a difference of 1.72 (95% confidence interval, 0.80 to 2.63), whereas in control participants, flow-mediated dilation decreased nonsignificantly from 10.8%+/- 4.7% to 10.6%+/- 5.4%, a difference of -0.20 (95% confidence interval, -1.24 to 0.84; P interaction =0.02). Endothelial cell protein expression of NF-B was greater in participants with autosomal dominant polycystic kidney disease (0.48 +/- 0.12 versus 0.41 +/- 0.10 [intensity versus human umbilical vein endothelial cell control]; P=0.03). However, circulating oxidative stress markers and bioactive lipid mediators did not significantly differ according to the autosomal dominant polycystic kidney disease diagnosis. Conclusions These results provide support for the hypothesis that vascular oxidative stress and inflammation develop with autosomal dominant polycystic kidney disease.