Renin-Angiotensin System Blockade in COVID-19: Good, Bad, or Indifferent?

Host-Cell Surface Binding Targets in SARS-CoV-2 for Drug Design

The ongoing pandemic of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) became a major public health threat to all countries worldwide. SARS-CoV-2 interactions with its receptor are the first step in the invasion of the host cell. The coronavirus spike protein (S) is crucial in binding to receptors on host cells. Additionally, targeting the SARS-CoV-2 viral receptors is considered a therapeutic option in this regard. In this review of literature, we summarized five potential host cell receptors, as host-cell surface bindings, including angiotensin-converting enzyme 2 (ACE2), neuropilin 1 (NRP-1), dipeptidyl peptidase 4 (DPP4), glucose regulated protein-78 (GRP78), and cluster of differentiation 147 (CD147) related to the SARS-CoV-2 infection. Among these targets, ACE2 was recognized as the main SARS-CoV-2 receptor, expressed at a low/moderate level in the human respiratory system, which is also involved in SARS-CoV-2 entrance, so the virus may utilize other secondary receptors. Besides ACE2, CD147 was discovered as a novel SARS-CoV-2 receptor, CD147 appears to be an alternate receptor for SARSCoV- 2 infection. NRP-1, as a single-transmembrane glycoprotein, has been recently found to operate as an entrance factor and enhance SARS Coronavirus 2 (SARS-CoV-2) infection under in-vitro. DPP4, which was discovered as the first gene clustered with ACE2, may serve as a potential SARS-CoV-2 spike protein binding target. GRP78 could be recognized as a secondary receptor for SARS-CoV-2 because it is widely expressed at substantially greater levels, rather than ACE2, in bronchial epithelial cells and the respiratory mucosa. This review highlights recent literature on this topic.

COVID-19, what could sepsis, severe acute pancreatitis, gender differences, and aging teach us?

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a potentially life-threatening disease, defined as Coronavirus Disease 19 (COVID-19). The most common signs and symptoms of this pathological condition include cough, fever, shortness of breath, and sudden onset of anosmia, ageusia, or dysgeusia. The course of COVID-19 is mild or moderate in more than 80% of cases, but it is severe or critical in about 14% and 5% of infected subjects respectively, with a significant risk of mortality. SARS-CoV-2 related infection is characterized by some pathogenetic events, resembling those detectable in other pathological conditions, such as sepsis and severe acute pancreatitis. All these syndromes are characterized by some similar features, including the coexistence of an exuberant inflammatory- as well as an anti-inflammatory-response with immune depression. Based on current knowledge concerning the onset and the development of acute pancreatitis and sepsis, we have considered these syndromes as a very interesting paradigm for improving our understanding of pathogenetic events detectable in patients with COVID-19. The aim of our review is: 1)to examine the pathogenetic mechanisms acting during the emergence of inflammatory and anti-inflammatory processes in human pathology; 2)to examine inflammatory and anti-inflammatory events in sepsis, acute pancreatitis, and SARS-CoV-2 infection and clinical manifestations detectable in patients suffering from these syndromes also according to the age and gender of these individuals; as well as to analyze the possible common and different features among these pathological conditions; 3)to obtain insights into our knowledge concerning COVID-19 pathogenesis. This approach may improve the management of patients suffering from this disease and it may suggest more effective diagnostic approaches and schedules of therapy, depending on the different phases and/or on the severity of SARS-CoV-2 infection.

Network pharmacology approach to decipher signaling pathways associated with target proteins of NSAIDs against COVID-19

Non-steroidal anti-inflammatory drugs (NSAIDs) showed promising clinical efficacy toward COVID-19 (Coronavirus disease 2019) patients as potent painkillers and anti-inflammatory agents. However, the prospective anti-COVID-19 mechanisms of NSAIDs are not evidently exposed. Therefore, we intended to decipher the most influential NSAIDs candidate(s) and its novel mechanism(s) against COVID-19 by network pharmacology. FDA (U.S. Food & Drug Administration) approved NSAIDs (19 active drugs and one prodrug) were used for this study. Target proteins related to selected NSAIDs and COVID-19 related target proteins were identified by the Similarity Ensemble Approach, Swiss Target Prediction, and PubChem databases, respectively. Venn diagram identified overlapping target proteins between NSAIDs and COVID-19 related target proteins. The interactive networking between NSAIDs and overlapping target proteins was analyzed by STRING. RStudio plotted the bubble chart of the KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway enrichment analysis of overlapping target proteins. Finally, the binding affinity of NSAIDs against target proteins was determined through molecular docking test (MDT). Geneset enrichment analysis exhibited 26 signaling pathways against COVID-19. Inhibition of proinflammatory stimuli of tissues and/or cells by inactivating the RAS signaling pathway was identified as the key anti-COVID-19 mechanism of NSAIDs. Besides, MAPK8, MAPK10, and BAD target proteins were explored as the associated target proteins of the RAS. Among twenty NSAIDs, 6MNA, Rofecoxib, and Indomethacin revealed promising binding affinity with the highest docking score against three identified target proteins, respectively. Overall, our proposed three NSAIDs (6MNA, Rofecoxib, and Indomethacin) might block the RAS by inactivating its associated target proteins, thus may alleviate excessive inflammation induced by SARS-CoV-2.

Outcomes of Hospitalized COVID-19 Patients Receiving Renin Angiotensin System Blockers and Calcium Channel Blockers

INTRODUCTION

Use of certain antihypertensive medications has been an area of interest during the COVID-19 pandemic, and several hypotheses have been developed regarding the effects of renin-angiotensin system blockers as well as calcium channel blockers in those infected with COVID-19. We seek to determine the association between exposure to ACEI, ARB, and CCB and outcomes in those admitted to the hospital with COVID-19 infection.

METHODS

This retrospective cohort study included 841 adult patients hospitalized with COVID-19 infection at the University of Chicago Medical Center between March 25 and June 22, 2020. Out of these 841, 453 patients had a personal history of hypertension. For the first part, we evaluated primary outcomes of in-hospital mortality and ICU admission in hospitalized COVID-19 patients based on their exposure to particular medications regardless of a personal history of hypertension and compared them with those who were not on these medications. For the second part, we evaluated the aforementioned outcomes in 453 patients with a personal history of hypertension based on their medication exposure. Secondary outcomes of length of stay, readmission rate, and new-onset dialysis requirement were also compared across the study groups.

RESULTS

Out of 841 patients, 111 (13.19%) were on ACEI/ARB (median age: 66.1, SD 15.4; 52.25% females) and 730 (86.80%) were not on them (median age: 56.6, SD 20.3; 50.14% females), while 277 (32.93%) used CCB (median age: 64.6, SD 15.2; 57.04% females) and 564 (67.06%) did not use CCB (median age: 54.6, SD 21.2; 47.16% females). After adjusting for demographics and covariates, neither ACEI/ARB nor CCB exposure was associated with any effect on mortality, but ACEI/ARB exposure was associated with 42% reduction in risk of ICU admissions (OR 0.58, 95% CI [0.35, 0.95], p value 0.03). In addition, combined use of ACEI/ARB and CCB was associated with statistically significant (45%) reduction in ICU admission (OR 0.55, 95% CI [0.32, 0.94], p value 0.029). Out of 453 patients with a personal history of hypertension, 85 (18.76%) were taking ACEI/ARB (median age 65, SD 15.6; 56.47% females) and 368 (81.24%) were not on ACEI/ARB (median age 62.8, SD 16.4; 54.89% females), while 208 (45.92%) out of 453 were on CCB (median age 65; SD 14.8; 60.1% females) and 245 (54.08%) were not on CCB (median age 61.7, SD 17.3; 51.02% females). In the fully adjusted model in this group, ACEI use was associated with 71% reduction in in-house mortality (OR 0.29, 95% CI [0.09, 0.93], p value 0.03).

DISCUSSION/CONCLUSION

Among all hospitalized patients with COVID-19 infection, exposure to ACEI/ARB, as well as combined exposure to ACEI/ARB and CCB, were associated with reduced incidence of ICU admissions. In those admitted patients who had a personal history of hypertension, there was a trend towards reduced in-hospital mortality in those exposed to ACEI.

Notable Developments for Vitamin D Amid the COVID-19 Pandemic, but Caution Warranted Overall: A Narrative Review

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel contagion that has infected over 113 million people worldwide. It is responsible for the coronavirus disease (COVID-19), which has cost the lives of 2.5 million people. Ergo, the global scientific community has been scrambling to repurpose or develop therapeutics to treat COVID-19. Dietary supplements and nutraceuticals are among those under consideration due to the link between nutritional status and patient outcomes. Overall, poor vitamin D status seems to be associated with an increased risk of COVID-19. Severely ill COVID-19 patients appear to be deficient or have suboptimal levels of serum 25-hydroxyvitamin D, a measure of vitamin D status. Consequently, vitamin D is now the subject of several prophylactic and therapeutic clinical trials. In this review, the general status of nutraceuticals and dietary supplements amid the pandemic is appraised, with a particular focus on vitamin D. Consumers should be aware of misinformation and unsubstantiated promises for products marketed for COVID-19 protection. However, maintaining a healthy diet and lifestyle will likely maintain health including optimum immune function that may affect patient outcomes. Those who are deficient in key nutrients such as vitamin D should consider lifestyle changes and potentially supplementation in consultation with their physician and/or registered dieticians.

Soluble ACE2 as a potential therapy for COVID-19

Soluble angiotensin-converting enzyme 2 (sACE2) could be a therapeutic option to treat coronavirus disease 2019 (COVID-19) infection. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) utilizes ACE2 receptors on cell surfaces to gain intracellular entry, making them an ideal target for therapy. High-affinity variants of sACE2, engineered using high-throughput mutagenesis, are capable of neutralizing COVID-19 infection as decoy receptors. These variants compete with native ACE2 present on cells by binding with spike (S) protein of SARS-CoV-2, making native ACE2 on cell surfaces available to convert angiotensin II to angiotensin-1,7, thus alleviating the exaggerated inflammatory response associated with COVID-19 infection. This article explores the use of sACE2 as potential therapy for COVID-19 infection.