Antioxidant properties of alpha-lipoic acid: effects on red blood membrane permeability and adaptation of isolated rat heart to reversible ischemia

International audienceThe aim of our work was to study (1) the antioxidant properties of lipoic acid (LA) and its reduced metabolite dihydrolipoic acid (DHLA) formed by reduction of LA and (2) the effects of treatment with LA and DHLA on (a) K ? efflux from human red blood cells and (b) postischemic recovery and oxidative stress in isolated perfused rat hearts challenged with an ischemia-reperfusion (IR) sequence. In vitro, we used xanthine and xanthine oxidase to generate superoxide anion, which is not directly measurable by electron paramagnetic resonance (EPR), but specifically oxidizes the spin probe CPH into an EPR-detectable long lasting CP • nitroxide radical. While 5 mM of LA was ineffective in reducing the kinetics of CP • nitroxide formation, DHLA was shown to lessen this rate in a dose-dependent manner and at 30 mM was even more efficient than 300 UI/ ml SOD. These results are in agreement with the fact that DHLA is able to directly scavenge superoxide anion. Red cells are a good model to investigate oxidative damage in biological membranes; hence, we used a suspension of erythrocytes incubated with 2,2 0-azobis(2-amidinopropane) hydrochloride (AAPH) which generates in vitro free radicals. DHLA provided more effective protection of red cells membranes than LA; DHLA was comparable to Trolox for its antioxidant potency. In vivo, treatment of rats (50 mg/kg/ day i.p. for 7 days) with LA induced a slight increase in coronary flow (CF) in isolated perfused hearts, after 30 min of global total ischemia. This effect was not associated with an improvement in contractile function and reduction of myocardial oxidative stress. In conclusion, because of their ability to scavenge free radicals, LA and to an even greater degree DHLA were able to protect the membranes of red blood cells. This finding suggests that LA and DHLA might be useful in the treatment of diseases associated with oxidative stress such as diabetes

Covered vs. Bare Metal Stents in the Reconstruction of the Aortic Bifurcation: Early and Midterm Outcomes from the COBRA European Multicentre Registry

Objective: To report outcomes following endovascular revascularisation for severe aorto-iliac occlusive disease (AIOD) using covered (CS) or bare metal (BMS) stent(s). Methods: This was a retrospective cohort study including patients who underwent treatment with CS or BMS for AIOD between November 2012 and March 2020 in 12 European centres. Outcome measures included death, freedom from target lesion revascularisation (TLR), major amputation, and major adverse cardiac and cerebrovascular events (MACCE). Results: Overall, 252 patients (53% males; mean age 65 ± 10 years) were included (102 with a bare metal and 150 with a covered aortic stent); 122 (48%) presented with chronic limb threatening ischaemia (CLTI). Severe arterial calcification was noted in > 65% of patients, 70% presented with Trans-Atlantic Societies Consensus (TASC) D lesions, 32% and 46% had aortic or iliac chronic total occlusion (CTO), respectively. Median follow up was 17 months (range 6 – 40; none lost to follow up). Median inpatient stay was two days (range two to four). During the first 30 days, two patients died (both with covered aortic stents, because of cardiovascular events), none required TLR, two (1%) patients had a major amputation (all presented with CLTI), and three (1%) had a MACCE. At 17 months, mortality (BMS 14% vs. CS 7%, hazard ratio [HR] 0.97, 95% confidence interval [CI] 0.42 – 2.26, p = .94, log rank test) and TLR (11% vs. 10%, HR 1.98, 95% CI 0.89 – 4.43, p = .095) did not differ statistically significantly between the two groups; only three patients had a major limb amputation during late follow up (all with a covered stent). In a multivariable model, the use of an aortic CS did not influence TLR. In a conditional Cox regression, however, the concomitant use of aortic and iliac CSs was associated with improved freedom from TLR. Conclusion: Endovascular reconstruction with aortic CSs or BMSs for severe AIOD showed comparable midterm performance. The use of both aortic and iliac CSs seems to be associated with reduced TLR

Dataset of the vascular e-Learning during the COVID-19 pandemic (EL-COVID) survey

10.1016/j.dib.2021.107442Data in Brief38107442