If the pandemic is less scary, the new emergency is the long Covid, which affects 1 in 3 people, even among young people, infected with the virus. According to estimates by the World Health Organization, 65 million in the world and 17 million in Europe would be people struggling with the long tail of the infection, a syndrome characterized by ‘fatigue’which causes prolonged and disabling fatigue, associated with muscle weakness, insomnia and tachycardia.
A group of Italian researchers has discovered that the person responsible for this “fatigue” is arginine, an amino acid naturally produced by the body, which stimulates nitric oxide, a key enzyme for correct immune and vascular function. The study on long Covid, conducted by the Agostino Gemelli University Hospital Foundation Irccs – Catholic University campus of Rome and being published in the International Journal of Molecular Sciences, is part of a line of research which, with a recent publication in the journal Nutrients, attested the efficacy of the synergistic action of arginine and vitamin C in reducing chronic tiredness and improving functional performance. In the new work, the group coordinated by Francesco Landi, past president of the Italian Society of Gerontology and Geriatrics (Sigg) and director of the Department of Orthopedic and Rheumatological Aging Sciences of the Gemelli Polyclinic, highlighted that an alteration of arginine metabolism occurs in patients with long Covid. It has also demonstrated that the administration of 1.6 grams of arginine and 500 mg of liposomal vitamin C for 28 days restores the metabolism of arginine to a normal level and effectively counteracts ‘fatigue’.
The study involved 57 people, 46 adults with long Covid eight months after diagnosis and 11 people matched by gender and age with no evidence of previous Sars-CoV-2 infections. The patients with long Covid were divided into two groups: 23 received the mix of arginine and liposomal vitamin C and the other 23 a placebo for a period of 28 days. «Before starting the treatment we measured the concentrations of arginine in the blood, observing significantly lower levels in patients with long Covid – says Landi, coordinator of the study -. At the end of the 28 days we discovered that the concentrations of arginine in the blood of patients with long Covid had risen, reaching ‘healthy’ levels such as those found in patients belonging to the control group”.
“We have demonstrated for the first time that arginine metabolism is altered in patients with long Covid compared to people with no history of Sars-Cov-2 infection – he underlines Matthew Tosatoco-author of the study and head of the post-Covid Day Hospital Operational Unit, Fondazione Policlinico Gemelli Irccs in Rome -. Arginine is an indispensable amino acid at the base of multiple functions and is mainly involved in the synthesis of nitric oxidewhich plays a key role in endothelial reactivity in response to the needs of different tissues, favoring a correct blood supply in relation to their needs, thus improving functional performance”.
«Currently in the absence of treatments available against a syndrome of which we still know very little, restoring the arginine values could represent a new effective integrative strategy – explains Landi – against the ‘fatigue’ from Long Covid, which can be associated with immune dysfunctions and vascular disease, which in turn increases the risk of developing cardiovascular disease.