Auxora Vs. Placebo for the Treatment of Patients with Severe COVID-19 Pneumonia: A Randomized Clinical Trial

Background: Calcium release-activated calcium (CRAC) channel inhibitors block proinflammatory cytokine release, preserve endothelial integrity and may effectively treat patients with severe COVID-19 pneumonia. Methods: CARDEA was a phase 2, randomized, double-blind, placebo-controlled trial evaluating the addition of Auxora, a CRAC channel inhibitor, to corticosteroids and standard of care in adults with severe COVID-19 pneumonia. The primary endpoint was time to recovery through Day 60, with secondary endpoints of all-cause mortality at Day 60 and Day 30. Due to declining rates of COVID-19 hospitalizations and encroachment of prohibited medications as standard of care, the trial was stopped early. Results: The pre-specified efficacy set consisted of the 261 patients with a baseline imputed PaO2/FiO2 £200 with 130 and 131 in the Auxora and placebo groups, respectively. Time to recovery was 7 vs. 10 days (P=0.0979) for patients who received Auxora vs. placebo, respectively. The all-cause mortality rate at Day 60 was 13.8% with Auxora vs. 20.6% with placebo (P=0.1449); Day 30 all-cause mortality was 7.7% and 17.6%, respectively (P=0.0165). Similar trends were noted in patients on high flow nasal cannula at baseline or those with a baseline imputed PaO2/FiO2 ≤100. Serious adverse events occurred less frequently in patients treated with Auxora vs. placebo. Conclusions: Auxora was safe and well tolerated with strong signals in both time to recovery and all-cause mortality through Day 60 in patients with severe COVID-19 pneumonia. Further studies of Auxora in combination with corticosteroids and other immunomodulatory agents are warranted.Trial registration: NCT04345614

Novel Targets and Interventions for Cognitive Complications of Diabetes

Diabetes and cognitive dysfunction, ranging from mild cognitive impairment to dementia, often coexist in individuals over 65 years of age. Vascular contributions to cognitive impairment/dementia (VCID) are the second leading cause of dementias under the umbrella of Alzheimer’s disease and related dementias (ADRD). Over half of dementia patients have VCID either as a single pathology or a mixed dementia with AD. While the prevalence of type 2 diabetes in individuals with dementia can be as high as 39% and diabetes increases the risk of cerebrovascular disease and stroke, VCID remains to be one of the less understood and less studied complications of diabetes. We have identified cerebrovascular dysfunction and compromised endothelial integrity leading to decreased cerebral blood flow and iron deposition into the brain, respectively, as targets for intervention for the prevention of VCID in diabetes. This review will focus on targeted therapies that improve endothelial function or remove iron without systemic effects, such as agents delivered intranasally, that may result in actionable and disease-modifying novel treatments in the high-risk diabetic population.

Hydroxysafflor Yellow A Blocks HIF-1α Induction of NOX2 and Protects ZO-1 Protein in Cerebral Microvascular Endothelium

Background: Zonula occludens-1 (ZO-1) protein ensures cerebrovascular integrity against brain ischemic injury. Hydroxysafflor yellow A (HSYA) is a major ingredient of safflower (Carthamus tinctorius L.) with anti-oxidative activity. Because conventional ROS scavengers display poor reactivity with endogenous ROS, this study investigated whether HSYA protected ZO-1 by targeting the enzymes responsible for ROS generation.Methords: Photothrombotic stroke model was prepared in mice to evaluate the protective effect of HSYA on cerebrovascular endothelium. The molecular regulation was investigated in cultured cerebral microvascular endothelial cells (bEnd.3 cells).Results: Oral administration of HSYA (50 mg/kg) reduced cerebral vascular leakage with ZO-1 protection in mice after stroke, largely due to suppression of ROS-associated inflammation. In LPS-stimulated bEnd.3 cells, HSYA increased the ratio of NAD+/NADH to restore Sirt1 induction, which bound to Von Hippel-Lindau (VHL) to ensure HIF-1α protein degradation. Although both NOX1 and NOX2 isoforms were inducible in endothelial cells, we identified NOX2 as the driving force of ROS production. Chromatin immunoprecipitation and luciferase report gene assay revealed that HIF-1α transcriptionally regulated p47phox and Nox2 subunits for the assembly of NOX2 complex, which was blocked by HSYA treatment, largely by reducing HIF-1α accumulation. Inflammation-associated lipid peroxidation impaired ZO-1 protein, but HSYA treatment attenuated carbonyl modification and thus prevented ZO-1 protein from 20S proteasome-mediated degradation, eventually protecting endothelial integrity. In microvascular ZO-1 deficient mice, we further confirmed that HSYA protected cerebrovascular integrity and attenuated ischemic injury dependent on ZO-1 protection. Conclusions: HSYA blocked HIF-1α/NOX2 signaling cascades to protect ZO-1 from proteasomal degradation, suggesting that targeting NOX2 in endothelium is a potential therapeutic strategy to protect against ischemic brain injury.

Endothelial Progenitor Cells and Rheumatoid Arthritis: Response to Endothelial Dysfunction and Clinical Evidences

Rheumatoid Arthritis (RA) is a chronic autoimmune inflammatory disease characterized by the swelling of multiple joints, pain and stiffness, and accelerated atherosclerosis. Sustained immune response and chronic inflammation, which characterize RA, may induce endothelial activation, damage and dysfunction. An equilibrium between endothelial damage and repair, together with the preservation of endothelial integrity, is of crucial importance for the homeostasis of endothelium. Endothelial Progenitor Cells (EPCs) represent a heterogenous cell population, characterized by the ability to differentiate into mature endothelial cells (ECs), which contribute to vascular homeostasis, neovascularization and endothelial repair. A modification of the number and function of EPCs has been described in numerous chronic inflammatory and auto-immune conditions; however, reports that focus on the number and functions of EPCs in RA are characterized by conflicting results, and discrepancies exist among different studies. In the present review, the authors describe EPCs’ role and response to RA-related endothelial modification, with the aim of illustrating current evidence regarding the level of EPCs and their function in this disease, to summarize EPCs’ role as a biomarker in cardiovascular comorbidities related to RA, and finally, to discuss the modulation of EPCs secondary to RA therapy.

Endothelial dysfunction contributes to severe COVID-19 in combination with dysregulated lymphocyte responses and cytokine networks

The systemic processes involved in the manifestation of life-threatening COVID-19 and in disease recovery are still incompletely understood, despite investigations focusing on the dysregulation of immune responses after SARS-CoV-2 infection. To define hallmarks of severe COVID-19 in acute disease (n = 58) and in disease recovery in convalescent patients (n = 28) from Hannover Medical School, we used flow cytometry and proteomics data with unsupervised clustering analyses. In our observational study, we combined analyses of immune cells and cytokine/chemokine networks with endothelial activation and injury. ICU patients displayed an altered immune signature with prolonged lymphopenia but the expansion of granulocytes and plasmablasts along with activated and terminally differentiated T and NK cells and high levels of SARS-CoV-2-specific antibodies. The core signature of seven plasma proteins revealed a highly inflammatory microenvironment in addition to endothelial injury in severe COVID-19. Changes within this signature were associated with either disease progression or recovery. In summary, our data suggest that besides a strong inflammatory response, severe COVID-19 is driven by endothelial activation and barrier disruption, whereby recovery depends on the regeneration of the endothelial integrity.

Peptidylglycine α-Amidating Monooxygenase And Adrenomedullin Measurement In Cirrhosis Suggesting Cardiomyopathy

Peptidylglycine α-amidating monooxygenase (PAM) is a processing enzyme involved in maturation of regulatory peptides. One product of PAM activity is adrenomedullin (bio-ADM), which regulates vascular tone and endothelial integrity. In this study, we examined PAM activity and bio-ADM concentrations in patients with various degrees of hepatic cirrhosis including the role of the liver in net release of the two markers. We enrolled 48 patients with cirrhosis and 16 control subjects: The patients were evenly distributed according to the Child-Turcotte classification. PAM activity was progressively increased in cirrhotic patients but without a net release across the liver, leg, or kidney. In contrast, bio-ADM concentrations were not only associated to severity of disease but also found to be directly released by the liver. Given the major expression of PAM in the heart, we propose that increased PAM activity in plasma from patients with cirrhosis may reflect cardiac involvement, e.g. cirrhotic cardiomyopathy.

Analysis of Cryopreservation Protocols and Their Harmful Effects on the Endothelial Integrity of Human Corneas

Corneal cryopreservation can partially solve the worldwide concern regarding donor cornea shortage for keratoplasties. In this study, human corneas were cryopreserved using two standard cryopreservation protocols that are employed in the Tissue Bank of the Teresa Herrera Hospital (Spain) to store corneas for tectonic keratoplasties (TK protocol) and aortic valves (AV protocol), and two vitrification protocols, VS55 and DP6. Endothelial viability and general corneal state were evaluated to determine the protocol that provides the best results. The potential corneal cryopreservation protocol was studied in detail taking into consideration some cryopreservation-related variables and the endothelial integrity and stroma arrangement of the resulting cryopreserved corneas. TK corneas showed mostly viable endothelial cells, while the others showed few (AV) or none (DP6 and VS55). The corneal structure was well maintained in TK and AV corneas. TK corneas showed endothelial acellular areas surrounded by injured cells and a normal-like stromal fiber arrangement. Cryoprotectant solutions of the TK protocol presented an increasing osmolality and a physiological pH value. Cooling temperature rate of TK protocol was of 1 °C/min to −40 °C and 3 °C/min to −120 °C, and almost all of dimethyl sulfoxide left the tissue after washing. Future studies should be done changing cryopreservation-related variables of the TK protocol to store corneas of optical grade.

Assessment of Platelet Indices Profile of Pregnant Women Attending University of Abuja Teaching Hospital, Nigeria

Platelets initiate hemostasis by aggregating at the site of injury and participate in ensuring endothelial integrity. A defect in this process could lead to intravascular blood loss. This case-control study sought to determine the platelet counts and indices among pregnant women in the University of Abuja Teaching Hospital Gwagwalada, Abuja, Nigeria. A total of 120 pregnant women as case and 60 non-pregnant women as control were enrolled for this study. Blood samples were collected in EDTA tubes, and complete platelet count and indices were carried out using an automated five-part haematology analyzer. The mean ± standard deviation of the platelets count among the pregnant women, 226.54 ± 69.76 109 cells/L was not significantly different from that of the non-pregnant women, 214.95 ± 52.22x 109 cells/L (p=0.295). There was a significant differences in mean platelets volume (MPV) of the case and control groups (p=0.036). After post-hoc test, the significant difference was between the pregnant women in 3rd trimester and the control group (p=0.014). However, there was no diffences in the mena platelets larger cell ratio and platelet distribution width in the case and control groups. Fifteen (11.0%) and 7 (12.1%) of the case and control control groups, respectively had mild thrombocytopenia. However, there was no significant association between pregnant status and thrombocytopenia (p=0.836). Based on these findngs, it can be infered that platelet count and MPV decreases while PDW increase with the progression of gestation age compared to the non-pregnant women.