Beneficial effects of L-Arginine in patients hospitalized for COVID-19: New insights from a randomized clinical trial

COVID‐19‐associated liver injury: Adding fuel to the flame

“…Besides, the use of adjuvant drugs can protect the liver and reduce secondary hepatic adverse reactions. Given that the relationship between amino acid metabolism and the liver, supplementation such as arginine, glutamine agents has been suggested to intervene in the treatment of COVID‐19 to provide hepatoprotective effect 163,195 . Furthermore, iron chelators, such as lactoferrin and deferoxamine, are potential in COVID‐19 treatment, at the same time, they have also been indicated to produce certain hepatoprotective effects by regulating iron metabolism 196,197 .…”

“…Given that the relationship between amino acid metabolism and the liver, supplementation such as arginine, glutamine agents has been suggested to intervene in the treatment of COVID-19 to provide hepatoprotective effect. 163,195 Furthermore, iron chelators, such as lactoferrin and deferoxamine, are potential in COVID-19 treatment, at the same time, they have also been indicated to produce certain hepatoprotective effects by regulating iron metabolism. 196,197 Studies have shown that some medicines have an impact on amino acid metabolism and produce other nonpharmacological effects, resulting in liver damage or poor drug efficacy, thus, when using these drugs, attention must be paid to their compatibility to prevent hepatotoxicity as much as possible.…”

Regulated Arginine Metabolism in Immunopathogenesis of a Wide Range of Diseases: Is There a Way to Pass between Scylla and Charybdis?

“…Oral administration of exogenous L-Arg vs. placebo in routine therapy in severe COVID-19 markedly reduced hospital stay and ventilatory support [ 180 ]. Moreover, it was recently shown that exogenous L-Arg substantially reduced peripheral blood level of pro-inflammatory cytokines IL-2, IL-6 and IFNγ and increased concentration of anti-inflammatory IL-10 in patients with COVID-19 [ 181 ]. The data obtained on the change in balance of pro- and anti-inflammatory cytokines were confirmed by clinical observations showing that along with L-Arg supplement, the discharge time from the hospital was shortened and the need for respiratory support was also decreased [ 181 ].…”

“…Moreover, it was recently shown that exogenous L-Arg substantially reduced peripheral blood level of pro-inflammatory cytokines IL-2, IL-6 and IFNγ and increased concentration of anti-inflammatory IL-10 in patients with COVID-19 [ 181 ]. The data obtained on the change in balance of pro- and anti-inflammatory cytokines were confirmed by clinical observations showing that along with L-Arg supplement, the discharge time from the hospital was shortened and the need for respiratory support was also decreased [ 181 ]. In contrast, another study showed that applying L-Arg for patients with severe COVID-19 pneumonia had no marked effect on disease outcome [ 182 ].…”