4-hydroxy-2-nonenal and Aortic-Aneurysm--Abdominal

Statins have been reported to suppress the progression of abdominal aortic aneurysm (AAA). However, the effects of statins on inflammatory processes and free radicals generation are poorly understood.. Wall samples from 51 patients (simvastatin patients, n = 34; non-statin patients, n = 17; matched by sex, age and aneurysm size) subjected to elective open AAA repair were analysed. We examined the effects of simvastatin on lipid peroxidation (4-hydroxy-trans-2-nonenal (4-HNE)), hydrogen peroxide (H(2)O(2)), tumour necrosis factor alpha (TNF-α) concentration, superoxide dismutase (SOD) and catalase (CAT) activity as well as nuclear factor kappa B (NF-κB) pathway activation in human AAA wall samples.. Treatment with simvastatin resulted in a decrease in 4-HNE and TNF-α concentration (median 4.18 μg/mg protein vs. 4.75, p = 0.012; median 10.33 pg/ml vs. 11.81, p = 0.026, respectively). CAT activity was higher in the simvastatin group (median 3.98 U ml vs. 3.19, p = 0.023). NF-κB expression was lower (p = 0.018) in the simvastatin group. However, simvastatin had little effect on H(2)O(2) concentration (p = 0.832) and SOD activity (p = 0.401).. Simvastatin inhibits free radicals and TNF-α generation and improves antioxidant capacity of human AAA wall tissue, possibly through the suppression of NF-κB activity. This may be one possible explanation how statins can inhibit AAA oxidative stress.

Topics: Aged; Aged, 80 and over; Aldehydes; Antioxidants; Aorta, Abdominal; Aortic Aneurysm, Abdominal; Austria; Case-Control Studies; Catalase; Female; Free Radicals; Humans; Hydrogen Peroxide; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Lipid Peroxidation; Male; Middle Aged; NF-kappa B; Oxidative Stress; Signal Transduction; Simvastatin; Superoxide Dismutase; Tumor Necrosis Factor-alpha

Chronic infusion of angiotensin II (AngII) into mice augments the development of abdominal aortic aneurysms (AAAs). Catalase is an important antioxidant enzyme in cellular peroxisome, and it physiologically maintains tissue and cellular redox homeostasis and thus plays a central role in defense against oxidative stress. The purpose of this study was to define whether deficiency of catalase influences AngII-induced AAAs. Male acatalasemic (C3H/AnLCsCs) mice and wild-type (C3H/AnLCsCs) mice (8-12 weeks old, N = 24 and 25, respectively) were fed a normal chow for 5 weeks. After 1 week of acclimtion, mice were infused subcutaneously with AngII (1000 ng·kg·min) by osmotic minipumps for 4 weeks. AngII increased systolic blood pressure equivalently in both groups. Acatalasemia had no effect on serum cholesterol concentrations. The body weight of acatalasemic mice was slightly greater than that of wild-type mice (P = 0.008). Although aortic catalase activity in acatalasemic mice was significantly low (P < 0.001), acatalasemia had no significant effect on the incidence of AngII-induced AAA formation (acatalasemia, 23%; wild, 21%), ex vivo measurement of maximal diameter of abdominal aorta (acatalasemia, 1.22 ± 0.29 mm; wild, 1.21 ± 0.17 mm), or aortic deposition of lipid peroxidation products such as 4-hydroxy-2-nonenal. The development of AngII-induced AAAs is independent of catalase.

Topics: Aldehydes; Angiotensin II; Animals; Aortic Aneurysm, Abdominal; Blood Pressure; Body Weight; Catalase; Cholesterol; Lipid Peroxidation; Male; Mice; Mice, Inbred C3H; Mice, Knockout; Oxidative Stress