Design, Synthesis, and Antiviral Evaluation of Sialic Acid Derivatives as Inhibitors of Newcastle Disease Virus Hemagglutinin-Neuraminidase: A Translational Study on Human Parainfluenza Viruses

Evaluating the Antiviral Potential of Polyherbal Formulation (Kabasura Kudineer) Against Monkeypox Virus: Targeting E5, Poxin, and DNA Polymerase Through Multifaceted Drug Discovery Approaches

The recent reemergence of the monkeypox pandemic in non-endemic regions has raised serious concerns regarding the possibility of a global outbreak. The study employed various modules of the Schrodinger suite through Maestro V 14.1 for molecular docking, MD simulations, MM-GBSA, and FMO. To explore the drug potential of Kabasura Kudineer against the key proteins of the Mpox virus: E5, poxin, and DNA polymerase, a total of 982 chemical constituents belonging to this herbal formulation were investigated. The molecular docking studies revealed that chlorogenic acid, chebulic acid, rosmarinic acid, and citric acid had high binding affinities for E5, with docking scores of -13.3289, -11.3933, -9.8999, and -9.59471 kcal/mol, respectively. Likewise, caffeic acid, citric acid, and plumbagic acid have good binding affinities for poxin with docking scores of -8.49023, -6.80386 and -5.91719 kcal/mol, respectively. Plumbagic acid and delphinidin have considerable binding affinities for DNA polymerase with docking scores of -7.57867 and -7.55301 kcal/mol, respectively. In the MD simulation, chlorogenic acid, chebulic acid, citric acid, and rosmarinic acid exhibited remarkable stability with strong binding affinities for the E5, poxin and DNA polymerase. We further explored the stability of the E5 complexes by calculating the binding free energy every 20 ns for 100 ns. The ΔG bind values of chlorogenic acid, chebulic acid, and rosmarinic acid were 61.10, 78.14, and 75.49 kcal/mol at 0 ns. Hence, the research suggests that this formulation has antiviral potential against Monkeypox and can be used to inhibit viral replication in hosts and boost the antiviral immune response.

Drug repurposing to tackle parainfluenza 3 based on multi-similarities and network proximity analysis

Given that there is currently no clinically approved drug or vaccine for parainfluenza 3 (PIV3), we applied a drug repurposing method based on disease similarity and chemical similarity to screen 2,585 clinically approved chemical drugs using PIV3 potential drugs BCX-2798 and zanamivir as our controls. Twelve candidate drugs were obtained after being screened with good disease similarity and chemical similarity (S > 0.50, T > 0.56). When docking them with the PIV3 target protein, hemagglutinin-neuraminidase (HN), only oseltamivir was docked with a better score than BCX-2798, which indicates that oseltamivir has an inhibitory effect on PIV3. After the distance (Z d c ) between the drug target of 14 drugs and the PIV3 disease target was measured by the network proximity method based on the PIV3 disease module, it was found that theZ d c values of amikacin, oseltamivir, ribavirin, and streptomycin were less than those of the control. Thus, oseltamivir is the best potential drug because it met all the above screening requirements. Additionally, to explore whether oseltamivir binds to HN stably, molecular dynamics simulation of the binding of oseltamivir to HN was carried out, and the results showed that the RMSD value of the complex tended to be stable within 100 ns, and the binding free energy of the complex was low (-10.60 kcal/mol). It was proved that oseltamivir screened by our drug repurposing method had the potential feasibility of treating PIV3.

Virus-like particles (VLPs): A promising platform for combating against Newcastle disease virus

The global poultry industry plays a pivotal role in providing eggs and meat for human consumption. However, outbreaks of viral disease, especially Newcastle virus disease (NDV), within poultry farms have detrimental effects on various zootechnical parameters, such as body weight gain, feed intake, feed conversion ratio, as well as the quality of egg and meat production. Cases of vaccine failure have been reported in regions where highly pathogenic strains of NDV are prevalent. To tackle this challenge, virus-like particles (VLPs) have emerged as a potential solution. VLPs closely resemble natural viruses, offering biocompatibility and immune-stimulating properties that make them highly promising for therapeutic applications against NDV. Hence, this review emphasizes the significance of NDV and the need for effective treatments. The manuscript will contain several key aspects, starting with an exploration of the structure and properties of NDV. Subsequently, the paper will delve into the characteristics and benefits of VLPs compared to conventional drug delivery systems. A comprehensive analysis of VLPs as potential vaccine candidates targeting NDV will be presented, along with a discussion on strategies for loading cargo into these NDV-targeting VLPs. The review will also examine various expression systems utilized in the production of NDV-targeting VLPs. Additionally, the manuscript will address future prospects and challenges in the field, concluding with recommendations for further research.

Interplay of Modified Sialic Acid Inhibitors and the Human Parainfluenza Virus 1 Hemagglutinin-Neuraminidase Active Site

In the search for effective antivirals against Paramyxoviridae, the dynamics of human parainfluenza virus type 1 hemagglutinin-neuraminidase (hPIV1-HN) inhibition offers a promising perspective. This study focuses on the potential of C5- and C4-modified 2,3-unsaturated sialic acid (DANA) inhibitors and highlights their interaction with the hPIV1-HN enzyme. We show that a strategic substitution, replacing the C5 isopropyl group in BCX 2798 with a trifluoroacetyl function, increases inhibitory potency 3- to 4-fold. At the same time, we explore the special properties of the catalytic site of hPIV1-HN, which harbors only small substituents and favors a C4 sulfonylamido function over a carbonyl function, in contrast to the C4 pocket of Newcastle disease virus hemagglutinin-neuraminidase (NDV-HN). Based on these findings, we present a newly identified potent inhibitor that has the preferred C5 trifluoroacetamido and C4 trifluorosulfonylamide groups. The results of this study pave the way for a deeper understanding of the C4 and C5 binding pockets of hPIV1-HN and promote the development of new, more selective inhibitors.

Conformationally locked sugar derivatives and analogues as potential neuraminidase inhibitors

The influenza virus remains a major health concern for mankind because it tends to mutate frequently and cause high morbidity. Influenza prevention and treatment are greatly aided by the use of antivirals. One such class of antivirals is neuraminidase inhibitors (NAIs), effective against influenza viruses. A neuraminidase on the virus's surface serves a vital function in viral propogation by assisting in the release of viruses from infected host cells. Neuraminidase inhibitors are the backbone in stoping such virus propagation thus helps in the treatment of influenza viruses infections. Two NAI medicines are licensed globally: Oseltamivir (Tamiflu™) and Zanamivir (Relanza™). There are two molecules that have acquired Japanese approval recently: Peramivir and Laninamivir, whereas Laninamivir octanoate is in Phase III clinical trials. The need for novel NAIs is due to frequent mutations in viruses and the rise in resistance against existing medication. The NA inhibitors (NAIs) are designed to have (oxa)cyclohexene scaffolds (a sugar scaffold) to mimic the oxonium transition state in the enzymatic cleavage of sialic acid. This review discusses in details and comprises all such conformationally locked (oxa)cyclohexene scaffolds and their analogues which have been recently designed and synthesized as potential neuraminidase inhibitors, thus as antiviral molecules. The structure-activity relationship of such diverese molecules has also been discussed in this review.

Analysis of the intramolecular 1,7-lactone of N-acetylneuraminic acid using HPLC-MS: relationship between detection and stability

A subclass of the sialic acid family consists of intramolecular lactones that may function as key indicators of physiological and pathological states. However, the existence of these compounds in free form is highly improbable, since they are unlikely to exist in an aqueous solution due to their lability. Current analytical method used to detect them in biological fluids has not recognized their reactivity in solution and is prone to misidentification. However, recent advances in synthetic methods for 1,7-lactones have allowed the preparation of these sialic acid derivatives as authentic reference standards. We report here the development of a new HPLC-MS method for the simultaneous detection of the 1,7-lactone of N-acetylneuraminic acid, its γ-lactone derivative, and N-acetylneuraminic acid that overcomes the limitations of the previous analytical procedure for their identification.