Lithium salts as a treatment for COVID-19: Pre-clinical outcomes.

INTRODUCTION: Identifying effective drugs for Coronavirus disease 2019 (COVID-19) is urgently needed. An efficient approach is to evaluate whether existing approved drugs have anti-SARS-CoV-2 effects. The antiviral properties of lithium salts have been studied for many years. Their anti-inflammatory and immune-potentiating effects result from the inhibition of glycogen synthase kinase-3. AIMS: To obtain pre-clinical evidence on the safety and therapeutic effects of lithium salts in the treatment of COVID-19. RESULTS: Six different concentrations of lithium, ranging 2-12 mmol/L, were evaluated. Lithium inhibited the replication of SARS-CoV-2 virus in a dose-dependent manner with an IC50 value of 4 mmol/L. Lithium-treated wells showed a significantly higher percentage of monolayer conservation than viral control, particularly at concentrations higher than 6 mmol/L, verified through microscopic observation, the neutral red assay, and the determination of N protein in the supernatants of treated wells. Hamsters treated with lithium showed less intense disease with fewer signs. No lithium-related mortality or overt signs of toxicity were observed during the experiment. A trend of decreasing viral load in nasopharyngeal swabs and lungs was observed in treated hamsters compared to controls. CONCLUSIONS: These results provide pre-clinical evidence of the antiviral and immunotherapeutic effects of lithium against SARS-CoV-2, which supports an advance to clinical trials on COVID-19's patients.

[The excretion pattern and protective capacity in rabbits orally immunized with attenuated strains of Vibrio cholerae O1 biotype El Tor]. / Estudio del patrón de excreción y la capacidad protectora en conejos inmunizados de forma oral con cepas atenuadas de Vibrio cholerae O1 biotipo El Tor.

In order to study the excretion patterns, colonization and protective capacity of live attenuated strains of Vibrio cholerae O1. El Tor, rabbits were immunized in New Zealand with these strains and their corresponding parental strains. 2 doses were administered by the model of oral inoculation in adult rabbits. Rabbits were rotated 2 weeks after the second dose by the model of ligated intestine with highly virulent strains of V. cholerae O1 Ogawa and Inaba serotypes and O139 serogroup. It was proved that the genetically manipulated strains do not effect the excretion patterns when they are compared with their parental strains. It was observed in the challenge a decrease in the levels of colonization of virulent strains of both serotypes, not only among the rabbits immunized with the attenuated strains, but also among those immunized with the parental strains in comparison with control animals immunized with the strain of Escherichia coli K-12, which means that there was certain degree of protection. In the case of the animals challenged with the O139 strain it was demonstrated that the protection is specific for each serogroup, since in this case there was no reduction of the colonization.