Possibilities of using amantadines in the setting of the novel coronavirus infection in patients with Parkinson's disease

The novel coronavirus infection pandemic prompted not only the development of vaccines, but also the study of the effectiveness of already known drugs with antiviral activity. These drugs include adamantanes.Objective: to assess possible mechanisms of antiviral action of amantadine and memantine.Patients and methods. The study included 75 patients with Parkinson's disease (PD): 49 (65.3%) women and 26 (34.7%) men. The age of the patients ranged from 37 to 88 years (mean age: 65±7 years). The duration of the disease varied from 1 to 25 years (mean 12±7 years). Among the monitored PD patients, 22 (29.3%) had a novel coronavirus infection. Of 22 patients with coronavirus infection, 8 (36.4%) patients received adamantanes (four – amantadine sulfate, three – amantadine hydrochloride, one – memantine) in the complex therapy of PD for at least 3 months. On average, the duration of adamantane administration was 8±5 months.Results and discussion. PD patients who received adamantanes were less likely to develop COVID-19 than those who did not take adamantanes (p<0.05). At the same time, there were no significant differences in gender, age, duration of the disease and concomitant pathology in the com pared groups (p>0.05). Among patients who received adamantanes, the disease proceeded more easily, the number of cases of pneumonia was 3 times less (odds ratio 3; 95% confidence interval 0.44–20.3). In this group, no lethal outcomes were recorded, however, due to the small sample of patients, the differences between the groups were not statistically significant (÷2=1.99; p>0.05).Conclusion. The results of a retrospective study showed that the use of amantadine and memantine in patients with PD may have an effect on reducing morbidity and mortality in the novel coronavirus infection. This is consistent with published clinical observations suggesting a possible protective effect of amantadine and memantine against coronavirus infection.

Polysaccharide-Based Organic Frameworks with Embedded Nanoparticles: Advanced SPR Study on the Antiviral Activity of Gold Composites Derived from Glucuronoxylomannan

The nanosized composites based on the natural polysaccharides and nanoparticles of noble metals are promising candidates for efficient antiviral drugs. However, the complexity of such objects, their diversity and novelty necessitate the development of new analytical methods for investigation of such supramolecular architectures. In this work, which was recently developed for SPR-based instrumentation, the concept of variative refraction (DViFA, density variations in fixed architectures) was used to elucidate the mechanism of the antiviral action of a polysaccharide with gold nanoparticles grown in it. The SPR data were confirmed by direct biological tests: the effect of the native polysaccharide glucuronoxylomannan (GXM) obtained from the fungus Ganoderma adspersum and gold nanocomposites thereon on the infection of Datura stramonium with tobacco mosaic virus (TMV) was investigated. Both drugs suppress the development of viral infections. However, if for high concentrations the characteristic activity of the composite is somewhat lower than for GXM, then with an increase in dilution, the effectiveness of the composite increases significantly, up to a twofold excess. It has been reasonably suggested that the mechanism of antiviral action is associated with the formation of clusters of viruses that are no longer capable of infecting cells.

Iota-carrageenan and xylitol inhibit SARS-CoV-2 in Vero cell culture

Last year observed a global pandemic caused by SARS-CoV-2 (severe acute respiratory syndrome-coronavirus 2) infection affecting millions of individuals worldwide. There is an urgent unmet need to provide an easily producible and affordable medicine to prevent transmission and provide early treatment for this disease. Since the nasal cavity and the rhinopharynx are the sites of initial replication of SARS-CoV-2, a nasal spray may be an effective option to target SARS-CoV-2 infection. In this study, we tested the antiviral action of three candidate nasal spray formulations against SARS-CoV-2 in vitro. We determined that iota-carrageenan in concentrations as low as 6 μg/mL inhibits SARS-CoV-2 in vitro. The concentrations of iota-carrageenan with activity against SARS-CoV-2 in vitro may be easily achieved through the application of nasal sprays as commonly used in several countries. Recently a double-blind, placebo-controlled study showed that iota-carrageenan in isotonic sodium chloride reduces ca. five times the risk of infection by SARS-CoV-2 in health care personnel. Further, xylitol at a concentration of 50 mg/mL (ca. 329 mM) was found to exert some antiviral action, though this preliminary finding needs further confirmation.

Potential of an Eco-Sustainable Probiotic-Cleaning Formulation in Reducing Infectivity of Enveloped Viruses

The COVID-19 pandemic has deeply influenced sanitization procedures, and high-level disinfection has been massively used to prevent SARS-CoV-2 spread, with potential negative impact on the environment and on the threat of antimicrobial resistance (AMR). Aiming to overcome these concerns, yet preserving the effectiveness of sanitization against enveloped viruses, we assessed the antiviral properties of the Probiotic Cleaning Hygiene System (PCHS), an eco-sustainable probiotic-based detergent previously proven to stably abate pathogen contamination and AMR. PCHS (diluted 1:10, 1:50 and 1:100) was tested in comparison to common disinfectants (70% ethanol and 0.5% sodium hypochlorite), in suspension and carrier tests, according with the European UNI EN 14476:2019 and UNI EN 16777:2019 standards. Human alpha- and beta-coronaviruses hCoV-229E and SARS-CoV-2, human herpesvirus type 1, human and animal influenza viruses, and vaccinia virus were included in the study. The results showed that PCHS was able to inactivate 99.99% of all tested viruses within 1-2 h of contact, both in suspension and on surface. Notably, while control disinfectants became inactive within 2 h after application, the PCHS antiviral action persisted up to 24 h post-application, suggesting that its use may effectively allow a continuous prevention of virus spread via contaminated environment, without worsening environmental pollution and AMR concern.

Seaweed-Derived Sulfated Polysaccharides as Potential Agents for Prevention and Treatment of Influenza and COVID-19

The review presents materials describing the seaweed-derived sulfated polysaccharides (SPS) as potential means for prevention and treatment of viral diseases of the respiratory tract, mainly influenza and COVID-19. The literature materials on the pathogenetic targets of influenza viruses and SARS-CoV-2, on the antiviral potential of SPS derived from red, brown and green algae, as well as on the mechanisms of antiviral action of these unique compounds are summarized. Seaweed SPS are characterized by high antiviral activity, good solubility, and almost complete absence of toxicity. Pathogens of respiratory infections do not form resistance under the SPS influence. The abovementioned facts allow us to consider these compounds as promising candidates for the creation of medicines, dietary supplements, and functional food products with antiviral and, above all, anti-influenza and anti-coronavirus activity on their basis in the future.

Can postbiotics show antiviral effects against Sars-CoV-2?

Severe Acute Respiratory Syndrome of Coronavirus-2 (Sars-CoV-2) is the causative agent of the new Coronavirus Disease (COVID-19) responsible for the current pandemic that threatens global health. Although some anti-COVID-19 therapeutic agents are under investigation, there is still no evidence of antiviral action against Sars-CoV-2. Research in the literature describes the success of probiotics in the treatment of viral infections from their byproducts, known as postbiotics, such as exopolysaccharides, hydrogen peroxide, and different bacteriocins. Based on these reports, we describe the main postbiotics that present antiviral actions against different viruses with a view to suggesting their use as possible therapeutic agents for COVID-19. The revised data show promising effects for using postbiotics as efficient vehicles against various types of viruses. However, further investigation of the underlying mechanisms is required for their indication against Sars-CoV-2 and other Sars-CoV infections.

Photosensitizing Antivirals

Antiviral action of various photosensitizers is already summarized in several comprehensive reviews, and various mechanisms have been proposed for it. However, a critical consideration of the matter of the area is complicated, since the exact mechanisms are very difficult to explore and clarify, and most publications are of an empirical and “phenomenological” nature, reporting a dependence of the antiviral action on illumination, or a correlation of activity with the photophysical properties of the substances. Of particular interest is substance-assisted photogeneration of highly reactive singlet oxygen (1O2). The damaging action of 1O2 on the lipids of the viral envelope can probably lead to a loss of the ability of the lipid bilayer of enveloped viruses to fuse with the lipid membrane of the host cell. Thus, lipid bilayer-affine 1O2 photosensitizers have prospects as broad-spectrum antivirals against enveloped viruses. In this short review, we want to point out the main types of antiviral photosensitizers with potential affinity to the lipid bilayer and summarize the data on new compounds over the past three years. Further understanding of the data in the field will spur a targeted search for substances with antiviral activity against enveloped viruses among photosensitizers able to bind to the lipid membranes.