ABSTRACT
Myocarditis has been discovered to be a significant complication of coronavirus disease 2019 (COVID-19), a condition caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. COVID-19 myocarditis seems to have distinct inflammatory characteristics, which make it unique to other viral etiologies. The incidence of COVID-19 myocarditis is still not clear as a wide range of figures have been quoted in the literature; however, it seems that the risk of developing myocarditis increases with more severe infection. Furthermore, the administration of the mRNA COVID-19 vaccine has been associated with the development of myocarditis, particularly after the second dose. COVID-19 myocarditis has a wide variety of presentations, ranging from dyspnea and chest pain to acute heart failure and possibly death. It is important to catch any cases of myocarditis, particularly those presenting with fulminant myocarditis which can be characterized by signs of heart failure and arrythmias. Initial work up for suspected myocarditis should include serial troponins and electrocardiograms. If myocardial damage is detected in these tests, further screening should be carried out. Cardiac magnetic resonance imagining and endomyocardial biopsy are the most useful tests for myocarditis. Treatment for COVID-19 myocarditis is still controversial; however, the use of intravenous immunoglobulins and corticosteroids in combination may be effective, particularly in cases of fulminant myocarditis. Overall, the incidence of COVID-19 myocarditis requires further research, while the use of intravenous immunoglobulins and corticosteroids in conjunction requires large randomized controlled trials to determine their efficacy.
ABSTRACT
The sphingolipids ceramide (Cer), ceramide-1-phosphate (C1P), sphingosine (Sph), and sphingosine-1-phosphate (S1P)) are key signaling molecules that regulate many patho-biological processes. During the last decade, they have gained increasing attention since they may participate in important and numerous retinal processes, such as neuronal survival and death, proliferation and migration of neuronal and vascular cells, inflammation, and neovascularization. Cer for instance has emerged as a key mediator of inflammation and death of neuronal and retinal pigment epithelium cells in experimental models of retinopathies such as glaucoma, age-related macular degeneration (AMD), and retinitis pigmentosa. S1P may have opposite biological actions, preventing photoreceptor and ganglion cell degeneration but also promoting inflammation, fibrosis, and neovascularization in AMD, glaucoma, and pro-fibrotic disorders. Alterations in Cer, S1P, and ceramide 1- phosphate may also contribute to uveitis. Furthermore, use of inhibitors that either prevent Cer increase or modulate S1P signaling, such as Myriocin, desipramine, and Fingolimod (FTY720), have been shown to preserve neuronal viability and retinal function. Collectively, the expanding role for these sphingolipids in the modulation of vital processes in retina cell types and in their dysregulation in retinal degenerations makes them attractive therapeutic targets.
