Angiotensin-converting enzyme as a new immunologic target for the new SARS-CoV-2

The effect of omega-3 supplements on the serum levels of ACE/ACE2 ratio as a potential key in cardiovascular disease: A randomized clinical trial in participants with vitamin D deficiency

Objective

The aim of this randomized controlled clinical trial was to determine the effect of the omega-3 fatty acid supplementations 300 mg per day for 8 weeks on the serum levels of ACE/ACE2 ratio in Jordanian participants with vitamin D deficiency (VDD).

Methods

The physical and clinical characteristic of individuals in both intervention and control randomized controlled clinical trial were measured and analyzed. The comparisons between the two groups and the changes in each group before and after taking omega-3 doses were studied through independent t test and paired t test, respectively. Possible factors that have a role in the changes were determined by multivariate stepwise regression. Follow-up period lasted 10 weeks.

Results

The sample consisted of 82 participants with VDD and a mean age of 37.85 ± 9.85 years. Omega-3 Supplements resulted in a significant decrease in serum ACE levels, ACE/ACE2 ratio and serum 25-hydroxy vitamin D (25OHD). While the change in serum ACE2 levels and serum triglycerides levels were insignificant. Also, a significant increase in serum LDL levels were observed.

Conclusion

It is possible that taking high doses of omega-3 fatty acid supplementations have positive effects on the heart and circulatory system and could protect from COVID-19 or decrease disease severity, in connection with a decrease in the ACE/ACE 2 ratio. On the other hand, omega-3 supplement may have negative effect on cardiovascular system due to the significant increase in serum LDL levels.

Targeting the Complement-Sphingolipid System in COVID-19 and Gaucher Diseases: Evidence for a New Treatment Strategy

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2)-induced disease (COVID-19) and Gaucher disease (GD) exhibit upregulation of complement 5a (C5a) and its C5aR1 receptor, and excess synthesis of glycosphingolipids that lead to increased infiltration and activation of innate and adaptive immune cells, resulting in massive generation of pro-inflammatory cytokines, chemokines and growth factors. This C5a-C5aR1-glycosphingolipid pathway- induced pro-inflammatory environment causes the tissue damage in COVID-19 and GD. Strikingly, pharmaceutically targeting the C5a-C5aR1 axis or the glycosphingolipid synthesis pathway led to a reduction in glycosphingolipid synthesis and innate and adaptive immune inflammation, and protection from the tissue destruction in both COVID-19 and GD. These results reveal a common involvement of the complement and glycosphingolipid systems driving immune inflammation and tissue damage in COVID-19 and GD, respectively. It is therefore expected that combined targeting of the complement and sphingolipid pathways could ameliorate the tissue destruction, organ failure, and death in patients at high-risk of developing severe cases of COVID-19.

ACE2 and Innate Immunity in the Regulation of SARS-CoV-2-Induced Acute Lung Injury: A Review

Despite the protracted battle against coronavirus acute respiratory infection (COVID-19) and the rapid evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), no specific and effective drugs have to date been reported. Angiotensin-converting enzyme 2 (ACE2) is a zinc metalloproteinase and a critical modulator of the renin-angiotensin system (RAS). In addition, ACE2 has anti-inflammatory and antifibrosis functions. ACE has become widely known in the past decade as it has been identified as the primary receptor for SARS-CoV and SARS-CoV-2, being closely associated with their infection. SARS-CoV-2 primarily targets the lung, which induces a cytokine storm by infecting alveolar cells, resulting in tissue damage and eventually severe acute respiratory syndrome. In the lung, innate immunity acts as a critical line of defense against pathogens, including SARS-CoV-2. This review aims to summarize the regulation of ACE2, and lung host cells resist SARS-CoV-2 invasion by activating innate immunity response. Finally, we discuss ACE2 as a therapeutic target, providing reference and enlightenment for the clinical treatment of COVID-19.