Oxidative stress in chronic lymphoedema

Background: Chronic lymphoedema is one of the most frequent and debilitating complications after surgical and radiological tumour treatment. Prevention and therapy of lymphoedema is therefore an important problem of the rehabilitation of those patients. Aim: To investigate whether chronic lymphoedema results in increased oxidative stress. Design: Prospective case-control study. Methods: We obtained venous blood samples from patients (n=38) with chronic lymphoedema and determined biomarkers of prooxidative reactions and of antioxidative defense system in the erythrocytes or blood plasma: reduced and oxidized glutathione (GSH and GSSG), and lipid peroxidation products such as malondialdehyde (MDA) and 4-hydroxynonenal (HNE). Healthy volunteers (n=90) and patients who had undergone surgical and/or radiotherapeutic treatment of tumours without consequent lymphoedema (n=20) acted as controls. Results: The blood of patients with chronic lymphoedema contained lower concentrations of GSH and higher levels of GSSG and of MDA and HNE, compared with the control group. MDA was increased by about three-fold in the serum of the lymphoedema patients. Accelerated free radical formation and lipid peroxidation processes were further demonstrated by the liberation of MDA and HNE into the blood serum after manual lymph drainage. Discussion: Our data demonstrate enhanced formation of reactive oxygen species (ROS) and accelerated lipid peroxidation processes in chronic lymphoedematous tissue. The strengthening of antioxidative defense mechanisms could be useful in the therapy of chronic lymphoedema.