Outbreak of SARS-CoV2: Pathogenesis of infection and cardiovascular involvement.

Since the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) has emerged from China, the infection (novel corona virus disease-2019, COVID-19) has affected many countries and led to many deaths worldwide. Like SARS-CoV, angiotencin converting enzyme (ACE)2 as a functional receptor for SARS-CoV2 is essential for the virus to make an entry into the cell. ACE2 is a part of Renin-Angiotensin-Aldosterone System, which is expressed in several organs that opposes the angiotensin (Ang) II functions by converting Ang II to Ang (1-7), the one with vasodilation effects. The death rate of COVID-19 is estimated to be approximately 3.4%; however, some comorbid conditions like underlying cardiovascular disease, hypertension, and diabetes increase the risk of mortality. In addition, cardiovascular involvement as a complication of SARS-CoV2 could be direct through either ACE2 receptors that are expressed tremendously in the heart, or by the surge of different cytokines or by acute respiratory distress syndrome-induced hypoxia. Traditional risk factors could aggravate the process of COVID-19 infection that urges the triage of these high-risk patients for SARS-CoV2. Currently, there is no effective, proven treatment or vaccination for COVID-19, but many investigators are struggling to find a treatment strategy as soon as possible. Some potential medications like chloroquine by itself or in combination with azithromycin and some protease inhibitors used for the treatment of COVID-19 have cardiovascular adverse effects, which should be kept in mind while the patients taking these medications are being closely monitored.

Kawasaki-like disease in children with COVID-19: A hypothesis.

With rapid spread of severe acute respiratory syndrome- corona virus-2 (SARS-COV-2) globally, some new aspects of the disease have been reported. Recently, it has been reported the incidence of Kawasaki-like disease among children with COVID-19. Since, children had been known to be less severely affected by the virus in part due to the higher concentration of Angiotensin converting enzyme (ACE)-2 receptor, this presentation has emerged concerns regarding the infection of children with SARS-COV2. ACE2 has anti-inflammatory, anti-fibrotic and anti-proliferative characteristics through converting angiotensin (Ag)-II to Ang (1-7). ACE2 receptor is downregulated by the SARS-COV through the spike protein of SARS-CoV (SARS-S) via a process that is tightly coupled with Tumor necrosis factor (TNF)-α production. TNF-α plays a key role in aneurysmal formation of coronary arteries in Kawasaki disease (KD). Affected children by COVID-19 with genetically-susceptible to KD might have genetically under-expression of ACE2 receptor that might further decrease the expression of ACE2 due to the downregulation of the receptor by the virus in these patients. It appears that TNF- α might be the cause and the consequence of the ACE2 receptor downregulation which results in arterial walls aneurysm. Conclusion: Genetically under-expression of ACE2 receptor in children with genetically-susceptible to KD who are infected with SARS-CoV-2 possibly further downregulates the ACE2 expression by TNF-α and leads to surge of inflammation including TNF-α and progression to Kawasaki-like disease.

Vaccination against atherosclerosis: An overview.

Atherosclerosis, an inflammatory disorder involving innate and adaptive immune responses with both atheroprotective and proatherogenic roles, is a life wasting and economic demanding disorder that continues to be the leading cause of morbidity and mortality worldwide. Thus, the need for a long-lasting and highly effective treatment has made researchers to find new strategies. Many efforts made thus far to reduce the burden of the disease have been toward the modification of cardiovascular risk factors. Vaccination against atherosclerosis has been investigated as a promising strategy to overcome the disorder. Several kinds of vaccination methods have been investigated mostly in mice, with promising results in the attenuation of atherosclerosis, inflammation, and lipid concentration. The most conflicting part of this strategy is finding appropriate antigens and adjuvants. Some antigens have been used, including OxLDL, apoB100, CETP, PCSK9, HSP60, MHC-II-derived peptides, and interleukins. The DNA-based vaccination method has opened a new window in this field. There is an increasing necessity for developing an effective, economical, long-lasting, accessible, and convenient vaccination method. There are large gaps in evidence for the selection of proper human sampling to test the vaccines, route of delivery, safety, strength, scheduling, and side effects, all of which must be considered in clinical trials in the future.