Harnessing the Antiviral and Anti-inflammatory Properties of Copper and Zinc Chlorophyllins: A Potential Therapeutic for COVID-19 Patients with Acute Respiratory Distress Syndrome

Abstract

Chlorophyllins are highly soluble non-toxic derivatives of chlorophyll α, containing a centralised metal at their core, known to target and treat cancer and immune-based diseases. The antiviral and anti-inflammatory effects of sodium copper chlorophyllin (SCC) and sodium zinc chlorophyllin (SZC), though documented, are rarely considered in treatment of viral respiratory diseases. Moreover, the use of chlorophyllins to potentially treat acute respiratory distress syndrome (ARDS), triggered by infection with respiratory viruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has yet to be studied. The published literature suggests antiviral and anti-inflammatory effects against SARS-CoV-2 and other enveloped respiratory viruses. Treatment with chlorophyllins inhibits virus entry, as well as replication and budding of viral progeny from the host cell in cell lines infected with enveloped respiratory viruses. Furthermore, treatments with SCC in vivo show diminished viral loads in animals infected with respiratory viruses, suggesting clinical antiviral capacity in treating viruses that cause ARDS-like manifestations, notably coronavirus disease 2019 (COVID-19). Similarly, SZC reduces inflammatory responses, while SCC may block key pro-inflammatory markers in vitro and in vivo, producing an anti-inflammatory effect against interleukin-6 and tumour necrosis factor α, two of the main antagonists associated with poorer outcomes in viral respiratory diseases, particularly among COVID-19 patients. This indicates a possible application in treating cytokine storm and hyperinflammation. Both SCC and SZC could act as a novel therapeutic in the treatment and prevention of ARDS and related respiratory complications, especially relevant to severe COVID-19 cases.