Myeloperoxidase evokes substantial vasomotor responses in isolated skeletal muscle arterioles of the rat

Postoperative vasoplegia in lung transplantation: incidence and relation to outcome

BACKGROUND

The incidence and clinical importance of vasoplegia after lung transplantation remains poorly studied. We describe the incidence of vasoplegia and its association with complications after lung transplantation.

METHODS

Perioperative data of 279 lung transplant recipients operated on from 2015 to 2020 were retrospectively analysed.

RESULTS

Vasoplegia occurred in 41.6% of patients after lung transplantation (mild, 31.0%; moderate, 55.2%; severe, 13.8%). Compared with non-vasoplegic patients, vasoplegic patients had a higher incidence of any acute kidney injury, defined by Kidney Disease Improving Global Outcomes (KDIGO) criteria (78.5% vs 65%, P=0.015), renal replacement therapy (47.4% vs 24.5%, P<0.001), and delayed chest closure (18.4% vs 9.2%, P=0.025); were ventilated longer (70 [32-368] vs 34 [19-105] h, P<0.001); and stayed longer in the ICU (12.9 [5-30] vs 6.8 [3-20] days, P<0.001). Mortality at 30 days and 1 yr was higher in patients with vasoplegia (11.2% vs 5.5% and 20.7% vs 11.7%, P=0.039, respectively). Severe vasoplegia represented a predictor of longer-term mortality (hazard ratio=1.65, P=0.008). Underlying infectious disease, increased BMI, higher preoperative pulmonary artery systolic pressure and bilirubin levels, lower glomerular filtration rate, and increased fresh frozen plasma transfusion were predictors of vasoplegia severity. Neutrophilia, leucocytosis, and increased C-reactive protein were associated with vasoplegia, but release of the neutrophil activation markers myeloperoxidase and heparin-binding protein was similar between groups.

CONCLUSIONS

Influenced by preoperative status as well as procedural factors and inflammatory response, vasoplegia is a common and critical condition after lung transplantation with worse short-term outcomes and long-term survival.

Amelioration of C-Reactive Protein and Lectin Like Oxidized Low Density Lipoprotein Receptor Complex Induced Endothelial Dysfunction by Oligomeric Proanthocyanidins

C-reactive protein (CRP) is a well-established biochemical marker for atherosclerosis. Modification of LDL inside the artery wall favors the elevation of this acute phase protein. Hence, this mechanism is considered an important factor to trigger the monocyte to macrophages differentiation which results in the formation of foam cells. Therefore, this key event should be targeted and focused on how this complex (OxLDL + CRP) proceeds to endothelial dysfunction. Oligomeric proanthocyanidins (OPC) is a well-known cardioprotective flavon-3-ols. The present study is challenged between the cardioprotective roles of OPC against the deleterious effect of OxLDL + CRP complex upon endothelial cells. Protein-protein docking was carried out between CRP and LOX-1. This docked protein complex was again docked with OPC to show the inhibitory mechanism of CRP binding with LOX-1. OPC showed a promising inhibitory mechanism against OxLDL + CRP complex. Docking studies showed that in the absence of ligands (OPC), binding of CRP and LOX-1 was greater and vice versa in the presence of ligands. Based on these molecular docking results, in vitro studies have been carried out. The monolayer of endothelial cells was incubated with THP-1 monocytes for 48 h, induced with OxLDL (10 μg/ml) + CRP (15 μg/ml) and cotreated with OPC (100 μg/ml). Morphological changes, cell migration assay, and capillary tube forming assay were carried out. Myeloperoxidase levels were estimated to determine the adhesion of monocytes onto EC monolayer. RT-PCR analysis of L-Selectin was also done. The quantification of NO levels and analysis of mRNA expressions of eNOS was to determine the nitric oxide demand caused due to OxLDL + CRP complex. LOX-1, scavenger receptor levels were analyzed by mRNA expression. Proinflammatory markers such as IL-6, MCP-1, and IL-1β were studied. Accumulation of ROS levels was measured fluorimetrically using DCF-DA staining. Mitochondrial membrane potential was determined by JC-1 dye and cell cycle analysis was done by FACS analysis. To emphasis the results, the OPC-treated group showed decreased levels of proinflammatory markers, LOX-1 and L-selectin levels. Endothelial nitric oxide levels were increased upon OPC treatment and reduction in the ROS levels was also observed. Endothelial cells apoptosis was prevented by OPC. To conclude, OxLDL + CRP complex inhibitory effects of OPC could maintain the normal homeostasis.

Inflammation in Human Heart Failure: Major Mediators and Therapeutic Targets

Inflammation has been recognized as a major pathophysiological contributor to the entire spectrum of human heart failure (HF), including HF with reduced ejection fraction, HF with preserved ejection fraction, acute HF and cardiogenic shock. Nevertheless, the results of several trials attempting anti-inflammatory strategies in HF patients have not been consistent or motivating and the clinical implementation of anti-inflammatory treatments for HF still requires larger and longer trials, as well as novel and/or more specific drugs. The present work reviews the different inflammatory mechanisms contributing to each type of HF, the major inflammatory mediators involved, namely tumor necrosis factor alpha, the interleukins 1, 6, 8, 10, 18, and 33, C-reactive protein and the enzymes myeloperoxidase and inducible nitric oxide synthase, and their effects on heart function. Furthermore, several trials targeting these mediators or involving other anti-inflammatory treatments in human HF are also described and analyzed. Future therapeutic advances will likely involve tailored anti-inflammatory treatments according to the patient's inflammatory profile, as well as the development of resolution pharmacology aimed at stimulating resolution of inflammation pathways in HF.

Differential Effects of E-Cigarette on Microvascular Endothelial Function, Arterial Stiffness and Oxidative Stress: A Randomized Crossover Trial

Propylene glycol and glycerol are electronic cigarettes vehicles allowing liquid vaporization and nicotine transport. The respective effects of these different constituents on the cardiovascular system are unknown. We assessed the differential effects of vehicles (propylene glycol and glycerol) and nicotine on microcirculatory function, arterial stiffness, hemodynamic parameters and oxidative stress. Twenty-five tobacco smokers were exposed to vaping with and without nicotine, and sham vaping, in a randomized, single blind, 3-period crossover design study. Neither sham-vaping nor vaping in the absence of nicotine resulted in modifications of cardiovascular parameters or oxidative stress. In contrast, vaping with nicotine: 1) impaired acetylcholine mediated vasodilation (mean ± standard error mean) (area under curve, perfusion unit (PU), 3385 ± 27PU to 2271 ± 27PU, p < 0.0001); 2) increased indices of arterial stiffness, namely augmentation index corrected for heart rhythm (−3.5 ± 1.5% to 1.9 ± 2.3%; p = 0.013) and pulse wave velocity (4.9 ± 0.1 m.s⁻¹ to 5.3 ± 0^.1 m.s⁻¹; p < 0.0001); 3) increased systolic and diastolic blood pressures as well as heart rate (all p < 0.0001) and finally; 4) raised plasma myeloperoxidase (median [interquartile range]) (13.6 ng.ml⁻¹ [10–17.7] to 18.9 ng.ml⁻¹ [12.2–54.4], p = 0.005). Our findings demonstrated that high temperature e-cigarette vehicle vaporization does not alter micro- and macro-vascular function, and oxidative stress, and that these effects are solely attributable to nicotine.