Introduction: Hereditary angioedema due to C1-INH deficiency (C1-INH-HAE) or with normal C1-INH is characterized by recurrent swellings due to uncontrolled production of vasoactive mediators, among which bradykinin (BK) is crucial. Through the binding and activation of the two human BK-receptors, kinins may have dual beneficial and deleterious effects in vascular and inflammation physiopathology by inducing oxidative stress. We aimed to assess the serum concentrations of advanced glycation end products (AGEs) and advanced oxidation protein products (AOPPs) in patients affected by HAE.
Material and methods: Blood samples were collected to measure the serum concentrations of AGEs and AOPPs by spectrofluorimetric and spectrophotometric methods in patients affected by C1-INH-HAE and FXII-HAE during the remission state.
Results: We showed that the circulating levels of AOPPs observed on control group (0.94 (0.36) nmol/mg) were significantly lower than those observed on the C1-INH-HAE group (1.68 (0.47) nmol/mg; p = 0.002) and FXII-HAE (1.50 (0.27) nmol/mg; p = 0.001). Moreover, the circulating levels of AGEs were significantly higher in C1-INH-HAE group (211.58 (151.05) AU/g; p = 0.02) than the FXII group (141.48 (89.59) AU/g), thus demonstrating a state of heightened oxidative stress.
Conclusions: Our observations show additional underlying events involved in HAE and are of central importance for further investigations of differences in bradykinin receptors signaling among the two disease subgroups.
Keywords: C1-inhibitor; bradykinin; hereditary angioedema; kinin; oxidative stress.