Ethan Lee

Introduction. Many types of calcium channels have been found in animal cells. The most important type of calcium channels is in the cellular membrane. They do not only rapidly transport calcium into the cytoplasm., but they also play important role in cellular membrane fusion.¹ Ca²⁺ functions in multiple ways in SARS-2 FP binding process. With help from Ca²⁺, FP firmly fuse with cell membrane and force the water molecules out of the headgroup region. Therefore, Calcium ion channel blockers may be a potential target in COVID-19 treatment². Methods.  Sources (2&3) investigated the Ca²⁺ ions’ inhibition on binding pocket. Ca²⁺ cations’ interaction with SARS-CoV FPs is studied by using Isothermal titration calorimetry (ITC). Circular Dichroism spectroscopy is employed to examine the secondary structure of the FP in membranes with different Ca²⁺ concentrations, structural transitions would reveal the relationship between Ca²⁺ dependent and the membrane ordering effect of SARS-1 FP. Other references (4&5) studied chosen Ca²⁺ channels blockers effects on COVID-19 patients through data collection and review. Results. Ca²⁺ promotes the folding of SARS-1 FP in the membrane.⁶ Ca²⁺ and NO signaling in pancreatic stellate cells reveals Ca²⁺ signaling in pancreatic macrophages in raising IL-18, and mediate Acute Pancreatitis.⁸ ARBs (losartan potassium and valsartan) and ACEIs (enalaprilat dehydrate and enalapril maleate) were also tested, but they failed to show any significant inhibition effects.² Calcium values distribution in COVID-19 patients shows left shift for both TCa and [Ca²⁺]. This left shift may be due to modified calcium absorption by SARS-CoV-2. It has been recognized as a biomarker predicting prognosis. However, this observation also can indicate the alteration of intracellular calcium homeostasis caused by the virus’ utilization.⁷ Conclusion. Calcium ion is closely related and influencing the replication and spread of SARS-CoV-2 virus. Calcium channel blockers are proved effective to reduce the rate of entry and replication of SARS-CoV-2 in vitro. Calcium ion channel blockers may work better in combination with ACE inhibitors. As of today, the effects of CCBs on treating COVID-19 is still under investigation. More clinical trials need to be conducted to investigate the effectiveness of calcium channel blockers.

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