"The possible implication of endothelin in the pathology of COVID-19-induced pulmonary hypertension".

COVID-19 pandemic has changed the world dramatically since was first reported in Wuhan city, China [1]. Not only as a respiratory illness that could lead to fatal respiratory failure, but also some evidences suggest that it can propagate as a chronic disease associated with a variety of persistent post COVID-19 pathologies that affect patients' life [2,3]. Pulmonary hypertension (PH) is one of the challenging diseases that may develop as a consequence of SARS-COV-2 infection in some COVID-19 survivors [4,5]. The vasopressor, proliferative, proinflammatory, and prothrombotic actions of endothelin [6] may be encountered in the COVID-19-induced PH pathology. And so, endothelin blockers may have an important role to restrict the development of serious PH outcomes with special precautions considering patients with significant hypoxemia.

Accelerated Repurposing and Drug Development of Pulmonary Hypertension Therapies for COVID-19 Treatment Using an AI-Integrated Biosimulation Platform.

The COVID-19 pandemic has reached over 100 million worldwide. Due to the multi-targeted nature of the virus, it is clear that drugs providing anti-COVID-19 effects need to be developed at an accelerated rate, and a combinatorial approach may stand to be more successful than a single drug therapy. Among several targets and pathways that are under investigation, the renin-angiotensin system (RAS) and specifically angiotensin-converting enzyme (ACE), and Ca2+-mediated SARS-CoV-2 cellular entry and replication are noteworthy. A combination of ACE inhibitors and calcium channel blockers (CCBs), a critical line of therapy for pulmonary hypertension, has shown therapeutic relevance in COVID-19 when investigated independently. To that end, we conducted in silico modeling using BIOiSIM, an AI-integrated mechanistic modeling platform by utilizing known preclinical in vitro and in vivo datasets to accurately simulate systemic therapy disposition and site-of-action penetration of the CCBs and ACEi compounds to tissues implicated in COVID-19 pathogenesis.

Echocardiographic assessment of the right ventricle in COVID -related acute respiratory syndrome.

In patients with the novel coronavirus (COVID-19) infection, the echocardiographic assessment of the right ventricle (RV) represents a pivotal element in the understanding of current disease status and in monitoring disease progression. The present manuscript is aimed at specifically describing the echocardiographic assessment of the right ventricle, mainly focusing on the most useful parameters and the time of examination. The RV direct involvement happens quite often due to preferential lung tropism of COVID-19 infection, which is responsible for an interstitial pneumonia characterized also by pulmonary hypoxic vasoconstriction (and thus an RV afterload increase), often evolving in acute respiratory distress syndrome (ARDS). The indirect RV involvement may be due to the systemic inflammatory activation, caused by COVID-19, which may affect the overall cardiovascular system mainly by inducing an increase in troponin values and in the sympathetic tone and altering the volemic status (mainly by affecting renal function). Echocardiographic parameters, specifically focused on RV (dimensions and function) and pulmonary circulation (systolic pulmonary arterial pressures, RV wall thickness), are to be measured in a COVID-19 patient with respiratory failure and ARDS. They have been selected on the basis of their feasibility (that is easy to be measured, even in short time) and usefulness for clinical monitoring. It is advisable to measure the same parameters in the single patient (based also on the availability of valid acoustic windows) which are identified in the first examination and repeated in the following ones, to guarantee a reliable monitoring. Information gained from a clinically-guided echocardiographic assessment holds a clinical utility in the single patients when integrated with biohumoral data (indicating systemic activation), blood gas analysis (reflecting COVID-19-induced lung damage) and data on ongoing therapies (in primis ventilatory settings).

ACE2 (Angiotensin-Converting Enzyme 2) in Cardiopulmonary Diseases: Ramifications for the Control of SARS-CoV-2.

Discovery of ACE2 (angiotensin-converting enzyme 2) revealed that the renin-angiotensin system has 2 counterbalancing arms. ACE2 is a major player in the protective arm, highly expressed in lungs and gut with the ability to mitigate cardiopulmonary diseases such as inflammatory lung disease. ACE2 also exhibits activities involving gut microbiome, nutrition, and as a chaperone stabilizing the neutral amino acid transporter, B0AT1, in gut. But the current interest in ACE2 arises because it is the cell surface receptor for the novel coronavirus, severe acute respiratory syndrome coronavirus-2, to infect host cells, similar to severe acute respiratory syndrome coronavirus-2. This suggests that ACE2 be considered harmful, however, because of its important other roles, it is paradoxically a potential therapeutic target for cardiopulmonary diseases, including coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2. This review describes the discovery of ACE2, its physiological functions, and its place in the renin-angiotensin system. It illustrates new analyses of the structure of ACE2 that provides better understanding of its actions particularly in lung and gut, shedding of ACE2 by ADAM17 (a disintegrin and metallopeptidase domain 17 protein), and role of TMPRSS2 (transmembrane serine proteases 2) in severe acute respiratory syndrome coronavirus-2 entry into host cells. Cardiopulmonary diseases are associated with decreased ACE2 activity and the mitigation by increasing ACE2 activity along with its therapeutic relevance are addressed. Finally, the potential use of ACE2 as a treatment target in COVID-19, despite its role to allow viral entry into host cells, is suggested.