Deguelin Attenuates Reperfusion Injury and Improves Outcome after Orthotopic Lung Transplantation in the Rat

The main goal of adequate organ preservation is to avoid further cellular metabolism during the phase of ischemia. However, modern preservation solutions do rarely achieve this target. In donor organs hypoxia and ischemia induce a broad spectrum of pathologic molecular mechanisms favoring primary graft dysfunction (PGD) after transplantation. Increased hypoxia-induced transcriptional activity leads to increased vascular permeability which in turn is the soil of a reperfusion edema and the enhancement of a pro-inflammatory response in the graft after reperfusion. We hypothesize that inhibition of the respiration chain in mitochondria and thus inhibition of the hypoxia induced mechanisms might reduce reperfusion edema and consecutively improve survival in vivo. In this study we demonstrate that the rotenoid Deguelin reduces the expression of hypoxia induced target genes, and especially VEGF-A, dose-dependently in hypoxic human lung derived cells. Furthermore, Deguelin significantly suppresses the mRNA expression of the HIF target genes VEGF-A, the pro-inflammatory CXCR4 and ICAM-1 in ischemic lungs vs. control lungs. After lung transplantation, the VEGF-A induced reperfusion-edema is significantly lower in Deguelin-treated animals than in controls. Deguelin-treated rats exhibit a significantly increased survival-rate after transplantation. Additionally, a downregulation of the pro-inflammatory molecules ICAM-1 and CXCR4 and an increase in the recruitment of immunomodulatory monocytes (CD163+ and CD68+) to the transplanted organ involving the IL4 pathway was observed. Therefore, we conclude that ischemic periods preceding reperfusion are mainly responsible for the increased vascular permeability via upregulation of VEGF. Together with this, the resulting endothelial dysfunction also enhances inflammation and consequently lung dysfunction. Deguelin significantly decreases a VEGF-A induced reperfusion edema, induces the recruitment of immunomodulatory monocytes and thus improves organ function and survival after lung transplantation by interfering with hypoxia induced signaling

Design and baseline characteristics of the finerenone in reducing cardiovascular mortality and morbidity in diabetic kidney disease trial

Background: Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials. Patients and Methods: The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate >= 25 mL/min/1.73 m(2) and albuminuria (urinary albumin-to-creatinine ratio >= 30 to <= 5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level alpha = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure. Conclusions: FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen. Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049

Myocardial Cell Death and Apoptosis in Hibernating Myocardium

AbstractObjectives. This study was designed to study apoptosis in hypoperfused hibernating myocardium subtending severe coronary stenosis.Background. Apoptosis contributes to myocyte death in acute myocardial infarction.Methods. A left anterior descending coronary artery stenosis was created in 13 pigs and maintained for 24 h (n = 4), 7 days (n = 5) and 4 weeks (n = 4) to reduce coronary blood flow by a mean of 34% with severe regional myocardial systolic dysfunction, as documented by echocardiography. Apoptosis was detected with an in situ end-labeling method and confirmed by “deoxyribonucleic acid laddering” on agarose-gel electrophoresis. The severity of apoptosis was expressed as the percentage of apoptotic myocyte nuclei and nonapoptotic myocardial nuclei.Results. Myocardial blood flow of the anterior left ventricular wall was reduced from 1.00 ± 0.18 to 0.66 ± 0.21 ml/min per g (p < 0.01), with a severe reduction of anterior regional wall thickening from a mean (±SD) of 39 ± 4% to 9 ± 8% (p < 0.01). There was no myocardial infarction in five pigs and minimal patchy infarction of ≤6% of the area at risk in eight pigs. Apoptotic myocytes were observed in the hibernating myocardial region in all pigs (4.8 ± 2.3%). Myocyte apoptosis was patchy in distribution and was found predominantly in the subendocardial myocardium (9.8 ± 4.6%) and rarely in the subepicardial myocardium (0.32 ± 0.45%). Apoptosis was found not only around focal fibrosis areas, but also in areas without fibrosis or patchy infarction. Apoptosis was found not only in 24-h hypoperfused myocardium, but also in 4-week hypoperfused myocardium. The severity of myocyte apoptosis correlated significantly with regional coronary blood flow reduction (r = 0.75, p < 0.01). No apoptosis was found in the normal control region.Conclusions. This study demonstrates that there is ongoing myocyte death through myocyte apoptosis in hypoperfused hibernating myocardium

Mucosal changes induced by ischemia-reperfusion injury in a jejunal loop transplanted in oropharynx

Tissues exposed to ischemia and reperfusion develop an inflammatory response. We investigate the morphological and immunological changes occurring in the mucosa of a jejunal loop transplanted in the oropharynx of a man undergoing circular pharyngolaryngectomy. Jejunal biopsies were collected during the transplantation procedures (cold and warm ischemia, reperfusion), during the 7 post-operative days through an exteriorized jejunal segment for flap monitoring, and 45 days after transplantation through an upper endoscopy. Matrix metalloproteinase (MMP)-3 and MMP-12 increase was accompanied by a parallel rise in apoptotic enterocytes, and by a concomitant reduction of surface area to volume ratio and enterocyte height. Goblet cell hyperplasia is coupled with Paneth cell disappearance at the crypt base. CD8-positive intraepithelial lymphocytes initially decrease, then they increase in accordance with the peak of enterocyte apoptosis. We identified alterations in lymphocyte infiltration, mucosal architecture and epithelial cell turnover, which may give a window to mechanisms of small bowel ischemia-reperfusion in humans