Updates of precision medicine in type 2 diabetes

Diabetes mellitus is prevalent worldwide and affects 1 in 10 adults. Despite the successful development of glucose-lowering drugs, such as glucagon-like peptide-1 (GLP-1) receptor agonists and sodium-glucose cotransporter-2 inhibitors recently, the proportion of patients achieving satisfactory glucose control has not risen as expected. The heterogeneity of diabetes determines that a one-size-fits-all strategy is not suitable for people with diabetes. Diabetes is undoubtedly more heterogeneous than the conventional subclassification, such as type 1, type 2, monogenic and gestational diabetes. The recent progress in genetics and epigenetics of diabetes has gradually unveiled the mechanisms underlying the heterogeneity of diabetes, and cluster analysis has shown promising results in the substratification of type 2 diabetes, which accounts for 95% of diabetic patients. More recently, the rapid development of sophisticated glucose monitoring and artificial intelligence technologies further enabled comprehensive consideration of the complex individual genetic and clinical information and might ultimately realize a precision diagnosis and treatment in diabetics.

Glucosaminylmuramyl dipeptide efficacy in post-COVID-19 patient rehabilitation treatment.

The COVID-19 pandemic has altered people's lifestyles around the world. Prevention of recurrent episodes of the disease and mitigation of its consequences are especially associated with effective post-COVID-19 rehabilitation in patients. The aim of the study was to evaluate the effects of the drug Likopid (glucosaminylmuramyl dipeptide, GMDP) for post-COVID-19 rehabilitation in patients. Material and methods. Patients who recovered from mild to moderate COVID-19 (n=60, mean age 54+/- 11.7 years) were randomized into the observation group (n=30, 15 men and 15 women) who received 2 courses of Licopid (1 mg twice a day) and the comparison group (n=30, 15 men and 15 women). Analysis of the phenotypic and functional characteristics of the innate immune cellular factors was carried out before the start of immunomodulatory therapy, immediately after the end of the course, and also after 6 months observations. In order to assess the quality of life of all patients, we used the SF-36 Health Status Survey and the Hospital Anxiety and Depression Scale questionnaires. Results. During assessing the effect of immunomodulatory therapy on the parameters of innate immunity of patients at the stage of rehabilitation after COVID-19, an increase in the protective cytolytic activity of CD16+ and CD8+Gr+ cells, as well as a persistent increase in TLR2, TLR4 and TLR9 expression was found, which indicates the antigen recognition recovery and presentation at the level of the monocytic link of the immune system. The use of GMDP as an immunomodulatory agent resulted in an 8-fold reduction in the frequency and severity of respiratory infections due to an increase in the total monocyte count. As a result of assessing patients' quality of life against the background of the therapy, a positive dynamic in role functioning was revealed in patients. In the general assessment of their health status, an increase in physical and mental well-being was noted during 6 months of observation. The comparison group showed no improvement in the psychoemotional state. Discussion. The study demonstrated the effectiveness of GMDP immunomodulatory therapy in correcting immunological parameters for post-COVID-19 rehabilitation in patients. The data obtained are consistent with the previously discovered ability of GMDP to restore impaired functions of phagocytic cells and induce the expression of their surface activation markers, which in turn contributes to an adequate response to pathogens. Conclusion. The study revealed that the correction of immunological parameters with the use of GMDP in COVID-19 convalescents contributed not only to a decrease in the frequency and severity of respiratory infections, but also to an improvement in the psycho-emotional state of patients, and a decrease in anxiety and depression.Copyright © Eco-Vector, 2023. All rights reserved.

HLA-B evolutionary divergence is associated with poor outcomes after SARS-CoV-2 infection

Objectives Human leukocyte antigens (HLA) are highly diverse transmembrane proteins that present viral peptides to T cells and launch pathogen-specific immune responses. We aim to investigate the correlation between HLA evolutionary divergence (HED), a surrogate for the capacity to present different peptides, and the outcomes of SARS-CoV-2 infection in a cohort from the St. Louis Metropolitan area. Methods We enrolled adult patients with SARS-CoV-2 infection confirmed by RT-PCR who were hospitalized at two tertiary hospitals in St. Louis between March and July 2020. Genomic DNA was extracted from peripheral blood and genotyped by next-generation sequencing (NGS). HLA alleles were assigned based on key-exon sequences (G group) and limited to the 2-field resolution. HED was calculated by Grantham distance, which considers the difference in composition, polarity, and molecular volume between each pair of amino acids from maternal and paternal HLA. The HED score was obtained for HLA class I (HLA-A, -B, and -C) genotypes using the HLAdivR package in R. Clinical data were collected retrospectively from electronic medical records. A poor outcome was defined as an admission to the intensive care unit (ICU), a need for mechanical ventilation, or death. A favorable outcome was defined as the absence of the above poor outcomes. Results A total of 234 patients were enrolled in this study, 96 being females (41%). The median age and BMI were 66 years old and 28.30 kg/m2, respectively. African Americans comprised 71.4% of the cohort. Only 19 patients (8.1%) presented with no comorbidity;the rest had one or more comorbidities, with cardiovascular diseases being the most common. A total of 137 (58.5%) patients had poor outcomes from SARS-CoV-2 infection, while 97 (41.5%) patients had a favorable outcome. We detected a significant association between higher HLA-B HED and favorable outcomes, with each 1-point increase in HLA-B HED associated with 8% increased probability for the composite endpoint (OR 1.08, 95% CI=1.01-1.16, P = 0.04). The HED scores calculated for HLA-A or HLA-C were not significantly different between patients with favorable or poor outcomes. In a multivariate logistic regression analysis, increased HLA-B HED score, younger age, and no comorbidity were independently associated with favorable outcomes (P = 0.02, P = 0.01, and P = 0.05, respectively). Conclusion Our study shows a significant correlation between lower HLA-B HED scores and poor outcomes after SARS-CoV-2 infection. This finding suggests that maximizing the presentation of diverse SARS-CoV-2 peptides by HLA-B alleles may improve the clearance of SARS-CoV-2. Further studies are warranted to understand the functional and mechanistic implications of this finding.

Cracking the Code of Complex Drug Modalities via Multidimensional Liquid Chromatography Coupled to Mass Spectrometry

Reducing the molecule complexity is achieved by reducing the molecule size after enzymatic digestion to produce smaller fragments more amenable to LC separation and tandem mass spectrometry (MS/MS) sequencing. Non-denaturing CEX chromatography, size-exclusion chromatogra- phy (SEC), hydrophobic interaction chromatography (HIC), and protein A modes can be easily coupled to reversed-phase LC (RPLC) because of the high aqueous conditions, enabling the versatile 4D-LC-MS systems with the use of alternative modes to 1D CEX, such as SEC or Protein A (6,7). [...]the nanopar-ticle size and free drug concentration are determined at the particle Level, whereas the encapsulated drug and lipids forming the layer are commonly characterized at the molecuar level after denaturing the lipid nanoparticle (LNP) via a surfactant. [...]MDLC-MS setups present a formidable opportunity to unify the characterization of drug delivery systems at the molecular and particle evels, which would enable their high throughput analysis.

Edible Insects as a Novel Source of Bioactive Peptides: A Systematic Review.

The production of food and feed to meet the needs of the growing world's population will soon become a serious challenge. In search for sustainable solutions, entomophagy is being proposed as an alternative source of proteins, with economic and environmental advantages when compared to meat. Edible insects are not only a valuable source of important nutrients, but their gastrointestinal digestion also originates small peptides with important bioactive properties. The present work intends to provide an exhaustive systematic review on research articles reporting bioactive peptides identified from edible insects, as demonstrated by in silico, in vitro, and/or in vivo assays. A total of 36 studies were identified following the PRISMA methodology, gathering 211 potentially bioactive peptides with antioxidant, antihypertensive, antidiabetic, antiobesity, anti-inflammatory, hypocholesterolemia, antimicrobial, anti-severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), antithrombotic, and immunomodulatory properties, originated from the hydrolysates of 12 different insect species. From these candidates, the bioactive properties of 62 peptides were characterized in vitro and 3 peptides were validated in vivo. Data establishing the scientific basis of the health benefits associated with the consumption of edible insects can be a valuable contribution to overcoming the cultural issues that hinder the introduction of insects in the Western diet.

Blood pH Analysis in Combination with Molecular Medical Tools in Relation to COVID-19 Symptoms.

The global outbreak of SARS-CoV-2/COVID-19 provided the stage to accumulate an enormous biomedical data set and an opportunity as well as a challenge to test new concepts and strategies to combat the pandemic. New research and molecular medical protocols may be deployed in different scientific fields, e.g., glycobiology, nanopharmacology, or nanomedicine. We correlated clinical biomedical data derived from patients in intensive care units with structural biology and biophysical data from NMR and/or CAMM (computer-aided molecular modeling). Consequently, new diagnostic and therapeutic approaches against SARS-CoV-2 were evaluated. Specifically, we tested the suitability of incretin mimetics with one or two pH-sensitive amino acid residues as potential drugs to prevent or cure long-COVID symptoms. Blood pH values in correlation with temperature alterations in patient bodies were of clinical importance. The effects of biophysical parameters such as temperature and pH value variation in relation to physical-chemical membrane properties (e.g., glycosylation state, affinity of certain amino acid sequences to sialic acids as well as other carbohydrate residues and lipid structures) provided helpful hints in identifying a potential Achilles heel against long COVID. In silico CAMM methods and in vitro NMR experiments (including 31P NMR measurements) were applied to analyze the structural behavior of incretin mimetics and SARS-CoV fusion peptides interacting with dodecylphosphocholine (DPC) micelles. These supramolecular complexes were analyzed under physiological conditions by 1H and 31P NMR techniques. We were able to observe characteristic interaction states of incretin mimetics, SARS-CoV fusion peptides and DPC membranes. Novel interaction profiles (indicated, e.g., by 31P NMR signal splitting) were detected. Furthermore, we evaluated GM1 gangliosides and sialic acid-coated silica nanoparticles in complex with DPC micelles in order to create a simple virus host cell membrane model. This is a first step in exploring the structure-function relationship between the SARS-CoV-2 spike protein and incretin mimetics with conserved pH-sensitive histidine residues in their carbohydrate recognition domains as found in galectins. The applied methods were effective in identifying peptide sequences as well as certain carbohydrate moieties with the potential to protect the blood-brain barrier (BBB). These clinically relevant observations on low blood pH values in fatal COVID-19 cases open routes for new therapeutic approaches, especially against long-COVID symptoms.

Neutrophil-Lymphocyte Ratio Predicting Case Severity in SARS-CoV-2 Infection: A Review.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is highly contagious and has taken an enormous toll on the worldwide quality of life and the global economy, in addition to the lives lost due to coronavirus disease 2019 (COVID-19). Precautionary measures and timely identification of the infected cases are essential to minimize the spread of SARS-CoV-2. Infection with this virus causes a spike in the proinflammatory cytokines, resulting in immune system-mediated host tissue damage, thus leading to mortality. Therefore, identifying mild, moderate, and severe cases is crucial to rendering appropriate care. Recent research has focused on identifying laboratory techniques to predict the case severity and outcome of COVID-19 cases. Low serum lymphocyte levels, low lymphocyte-to-C-reactive protein ratio, low platelet-to-lymphocyte ratio, thrombocytopenia, and high neutrophil-lymphocyte ratio (NLR) have been observed in critical infections. NLR might be a prognostic marker for disease severity. Severe cases can be triaged at hospital admission for proper treatment planning and to reduce mortality. This review highlights the potential role of NLR hematological assay in SARS-CoV-2 infection and the mechanism of neutrophilic-induced host tissue damage.

Identification of differences in the magnitude and specificity of SARS-CoV-2 nucleocapsid antibody responses in naturally infected and vaccinated individuals.

As there are limited data on B cell epitopes for the nucleocapsid protein in SARS-CoV-2, we sought to identify the immunodominant regions within the N protein, recognized by patients with varying severity of natural infection with the Wuhan strain (WT), delta, omicron and in those who received the Sinopharm vaccines, which is an inactivated, whole virus vaccine.Using overlapping peptides representing the N protein, with an in-house ELISA, we mapped the immunodominant regions within the N protein, in seronegative (n=30), WT infected (n=30), delta infected (n=30), omicron infected+vaccinated (n=20) and Sinopharm (BBIBP-CorV) vaccinees (n=30). We then investigated the sensitivity and specificity of these immunodominant regions and analysed their conservation with other SARS-CoV-2 variants of concern, seasonal human coronaviruses and bat Sarbecoviruses. We identified four immunodominant regions aa 29-52, aa 155-178, aa 274 to 297 and aa 365 to 388, were highly conserved within SARS-CoV-2 and the bat coronaviruses. The magnitude of responses to these regions varied based on the infecting SARS-CoV-2 variants, >80% of individuals gave responses above the positive cut-off threshold to many of the four regions, with some differences with individuals who were infected with different VoCs. These regions were found to be 100% specific, as none of the seronegative individuals gave any responses. As these regions were highly specific with high sensitivity, they have a potential to be used to develop diagnostic assays and to be used in development of vaccines.

Zn2+ and Cu2+ Interaction with the Recognition Interface of ACE2 for SARS-CoV-2 Spike Protein.

The spike protein (S) of SARS-CoV-2 is able to bind to the human angiotensin-converting enzyme 2 (ACE2) receptor with a much higher affinity compared to other coronaviruses. The binding interface between the ACE2 receptor and the spike protein plays a critical role in the entry mechanism of the SARS-CoV-2 virus. There are specific amino acids involved in the interaction between the S protein and the ACE2 receptor. This specificity is critical for the virus to establish a systemic infection and cause COVID-19 disease. In the ACE2 receptor, the largest number of amino acids playing a crucial role in the mechanism of interaction and recognition with the S protein is located in the C-terminal part, which represents the main binding region between ACE2 and S. This fragment is abundant in coordination residues such as aspartates, glutamates, and histidine that could be targeted by metal ions. Zn2+ ions bind to the ACE2 receptor in its catalytic site and modulate its activity, but it could also contribute to the structural stability of the entire protein. The ability of the human ACE2 receptor to coordinate metal ions, such as Zn2+, in the same region where it binds to the S protein could have a crucial impact on the mechanism of recognition and interaction of ACE2-S, with consequences on their binding affinity that deserve to be investigated. To test this possibility, this study aims to characterize the coordination ability of Zn2+, and also Cu2+ for comparison, with selected peptide models of the ACE2 binding interface using spectroscopic and potentiometric techniques.

Antimicrobial Peptides: Challenging Journey to the Pharmaceutical, Biomedical, and Cosmeceutical Use.

Antimicrobial peptides (AMPs), or host defence peptides, are short proteins in various life forms. Here we discuss AMPs, which may become a promising substitute or adjuvant in pharmaceutical, biomedical, and cosmeceutical uses. Their pharmacological potential has been investigated intensively, especially as antibacterial and antifungal drugs and as promising antiviral and anticancer agents. AMPs exhibit many properties, and some of these have attracted the attention of the cosmetic industry. AMPs are being developed as novel antibiotics to combat multidrug-resistant pathogens and as potential treatments for various diseases, including cancer, inflammatory disorders, and viral infections. In biomedicine, AMPs are being developed as wound-healing agents because they promote cell growth and tissue repair. The immunomodulatory effects of AMPs could be helpful in the treatment of autoimmune diseases. In the cosmeceutical industry, AMPs are being investigated as potential ingredients in skincare products due to their antioxidant properties (anti-ageing effects) and antibacterial activity, which allows the killing of bacteria that contribute to acne and other skin conditions. The promising benefits of AMPs make them a thrilling area of research, and studies are underway to overcome obstacles and fully harness their therapeutic potential. This review presents the structure, mechanisms of action, possible applications, production methods, and market for AMPs.

Mitochondrial N-formyl methionine peptides contribute to exaggerated neutrophil activation in patients with COVID-19.

Neutrophil dysregulation is well established in COVID-19. However, factors contributing to neutrophil activation in COVID-19 are not clear. We assessed if N-formyl methionine (fMet) contributes to neutrophil activation in COVID-19. Elevated levels of calprotectin, neutrophil extracellular traps (NETs) and fMet were observed in COVID-19 patients (n = 68), particularly in critically ill patients, as compared to HC (n = 19, p < 0.0001). Of note, the levels of NETs were higher in ICU patients with COVID-19 than in ICU patients without COVID-19 (p < 0.05), suggesting a prominent contribution of NETs in COVID-19. Additionally, plasma from COVID-19 patients with mild and moderate/severe symptoms induced in vitro neutrophil activation through fMet/FPR1 (formyl peptide receptor-1) dependent mechanisms (p < 0.0001). fMet levels correlated with calprotectin levels validating fMet-mediated neutrophil activation in COVID-19 patients (r = 0.60, p = 0.0007). Our data indicate that fMet is an important factor contributing to neutrophil activation in COVID-19 disease and may represent a potential target for therapeutic intervention.

A Web-Based Method for the Identification of IL6-Based Immunotoxicity in Vaccine Candidates.

Interleukin 6 (IL6) is a major pro-inflammatory cytokine that plays a pivotal role in both innate and adaptive immune responses. In the past, a number of studies reported that high level of IL6 promotes the proliferation of cancer, autoimmune disorders, and cytokine storm in COVID-19 patients. Thus, it is extremely important to identify and remove the antigenic regions from a therapeutic protein or vaccine candidate that may induce IL6-associated immunotoxicity. In order to overcome this challenge, our group has developed a computational tool, IL6pred, for discovering IL6-inducing peptides in a vaccine candidate. The aim of this chapter is to describe the potential applications and methodology of IL6pred. It sheds light on the prediction, designing, and scanning modules of IL6pred webserver and standalone package ( https://webs.iiitd.edu.in/raghava/il6pred/ ).

Novel Polymyxin-Inspired Peptidomimetics Targeting the SARS-CoV-2 Spike:hACE2 Interface.

Though the bulk of the COVID-19 pandemic is behind, the search for effective and safe anti-SARS-CoV-2 drugs continues to be relevant. A highly pursued approach for antiviral drug development involves targeting the viral spike (S) protein of SARS-CoV-2 to prevent its attachment to the cellular receptor ACE2. Here, we exploited the core structure of polymyxin B, a naturally occurring antibiotic, to design and synthesize unprecedented peptidomimetics (PMs), intended to target contemporarily two defined, non-overlapping regions of the S receptor-binding domain (RBD). Monomers 1, 2, and 8, and heterodimers 7 and 10 bound to the S-RBD with micromolar affinity in cell-free surface plasmon resonance assays (KD ranging from 2.31 µM to 2.78 µM for dimers and 8.56 µM to 10.12 µM for monomers). Although the PMs were not able to fully protect cell cultures from infection with authentic live SARS-CoV-2, dimer 10 exerted a minimal but detectable inhibition of SARS-CoV-2 entry in U87.ACE2+ and A549.ACE2.TMPRSS2+ cells. These results validated a previous modeling study and provided the first proof-of-feasibility of using medium-sized heterodimeric PMs for targeting the S-RBD. Thus, heterodimers 7 and 10 may serve as a lead for the development of optimized compounds, which are structurally related to polymyxin, with improved S-RBD affinity and anti-SARS-CoV-2 potential.

Antimicrobial peptides: Defending the mucosal epithelial barrier.

The recent epidemic caused by aerosolized SARS-CoV-2 virus illustrates the importance and vulnerability of the mucosal epithelial barrier against infection. Antimicrobial proteins and peptides (AMPs) are key to the epithelial barrier, providing immunity against microbes. In primitive life forms, AMPs protect the integument and the gut against pathogenic microbes. AMPs have also evolved in humans and other mammals to enhance newer, complex innate and adaptive immunity to favor the persistence of commensals over pathogenic microbes. The canonical AMPs are helictical peptides that form lethal pores in microbial membranes. In higher life forms, this type of AMP is exemplified by the defensin family of AMPs. In epithelial tissues, defensins, and calprotectin (complex of S100A8 and S100A9) have evolved to work cooperatively. The mechanisms of action differ. Unlike defensins, calprotectin sequesters essential trace metals from microbes, which inhibits growth. This review focuses on defensins and calprotectin as AMPs that appear to work cooperatively to fortify the epithelial barrier against infection. The antimicrobial spectrum is broad with overlap between the two AMPs. In mice, experimental models highlight the contribution of both AMPs to candidiasis as a fungal infection and periodontitis resulting from bacterial dysbiosis. These AMPs appear to contribute to innate immunity in humans, protecting the commensal microflora and restricting the emergence of pathobionts and pathogens. A striking example in human innate immunity is that elevated serum calprotectin protects against neonatal sepsis. Calprotectin is also remarkable because of functional differences when localized in epithelial and neutrophil cytoplasm or released into the extracellular environment. In the cytoplasm, calprotectin appears to protect against invasive pathogens. Extracellularly, calprotectin can engage pathogen-recognition receptors to activate innate immune and proinflammatory mechanisms. In inflamed epithelial and other tissue spaces, calprotectin, DNA, and histones are released from degranulated neutrophils to form insoluble antimicrobial barriers termed neutrophil extracellular traps. Hence, calprotectin and other AMPs use several strategies to provide microbial control and stimulate innate immunity.

Molecular Docking and Simulation Analysis of Cyclopeptides as Anticancer Agents

Background: Cancer is a leading cause of death for people worldwide, in addition to the rise in mortality rates attributed to the Covid epidemic. This allows scientists to do additional research. Here, we have selected Integerrimide A, cordy heptapeptide, and Oligotetrapeptide as the three cyclic proteins that will be further studied and investigated in this context.Methods: Docking research was carried out using the protein complexes 1FKB and 1YET, downloaded from the PDB database and used in the docking investigations. Cyclopeptides have been reported to bind molecularly to human HSP90 (Heat shock protein) and FK506. It was possible to locate HSP90 in Protein Data Banks 1YET and 1FKB. HSP90 was retrieved from Protein Data Bank 1YET and 1FKB. Based on these findings, it is possible that the anticancer effects of Int A, Cordy, and Oligo substances could be due to their ability to inhibit the mTOR rapamycin binding domain and the HSP90 Geldanamycin binding domain via the mTOR and mTOR chaperone pathways. During the calculation, there were three stages: system development, energy reduction, and molecular dynamics (also known as molecular dynamics). Each of the three compounds demonstrated a binding affinity for mTOR's Rapamycin binding site that ranged from -6.80 to -9.20 Kcal/mol (FKB12).Results: An inhibition constant Ki of 181.05 nM characterized Cordy A with the highest binding affinity (-9.20 Kcal/mol). Among the three tested compounds, Cordy A was selected for MD simulation. HCT116 and B16F10 cell lines were used to test each compound's anticancer efficacy. Doxorubicin was used as a standard drug. The cytotoxic activity of substances Int A, Cordy A, and Oligo on HCT116 cell lines was found to be 77.65 μM, 145.36 μM, and 175.54 μM when compared to Doxorubicin 48.63 μM, similarly utilizing B16F10 cell lines was found to be 68.63 μM, 127.63 μM, and 139.11 μM to Doxorubicin 45.25 μM.Conclusion: Compound Cordy A was more effective than any other cyclic peptides tested in this investigation.

Precise Epitope Organization with Self‐adjuvant Framework Nucleic Acid for Efficient COVID‐19 Peptide Vaccine Construction

Peptide vaccines have advantages in easy fabrication and high safety, but their effectiveness is hampered by the poor immunogenicity of the epitopes themselves. Herein, we constructed a series of framework nucleic acids (FNAs) with regulated rigidity and size to precisely organize epitopes in order to reveal the influence of epitope spacing and carrier rigidity on the efficiency of peptide vaccines. We found that assembling epitopes on rigid tetrahedral FNAs (tFNAs) with the appropriate size could efficiently enhance their immunogenicity. Further, by integrating epitopes from SARS‐CoV‐2 on preferred tFNAs, we constructed a COVID‐19 peptide vaccine which could induce high titers of IgG against the receptor binding domain (RBD) of SARS‐CoV‐2 spike protein and increase the ratio of memory B and T cells in mice. Considering the good biocompatibility of tFNAs, our research provides a new idea for developing efficient peptide vaccines against viruses and possibly other diseases.

Inhibition of the SARS-CoV-2 Main Protease by Isoquercitrin γ-Cyclodextrin Inclusion Complex Formulations: A Biochemical and In Silico Study

The main protease (Mpro) of SARS-CoV-2 is a well-established drug target for rational drug design of COVID-19 inhibitors. To address the serious challenge of COVID-19, we have performed biochemical inhibition screens with recombinantly expressed SARS-CoV-2 main protease (Mpro). A fluorescent assay was used to identify the flavonoid isoquercitrin as an Mpro inhibitor. Both isoquercitrin encapsulated in γ-cyclodextrin (inclusion complex formulations) and alone inhibited SARS-CoV-2 Mpro. For isoquercitrin, a Ki value of 32 μM (IC50 = 63 μM) was obtained. Isoquercitrin γ-cyclodextrin inclusion complex formulations additionally inhibited Zika virus NS2B-NS3pro leading to an IC50 value of 98 μM. Formulations containing the other flavonoid compounds diosmetin-7-O-glucoside, hesperetin-7-O-glucoside, and naringenin-7-O-glucoside did not inhibit SARS-CoV-2 Mpro. Steady-state kinetics indicate that the inhibition mechanism of Mpro by isoquercitrin is potentially competitive. Molecular modeling studies carried out with MM/PBSA confirm the likely modes of isoquercitrin binding to both proteases. These modeling results can be used in the development of structural analogs of isoquercitrin with better inhibitory profiles and potential candidates for anti-coronavirus drugs. Since the targeted proteases are essential for viral activity, the delivery isoquercitrin-cyclodextrin inclusion complex formulations could be of great interest for the development of future antiviral drugs to target intracellular virus proteins or other components.

Glucosaminylmuramyl dipeptide efficacy in post-COVID-19 patient rehabilitation treatment.

The COVID-19 pandemic has altered people's lifestyles around the world. Prevention of recurrent episodes of the disease and mitigation of its consequences are especially associated with effective post-COVID-19 rehabilitation in patients. The aim of the study was to evaluate the effects of the drug Likopid (glucosaminylmuramyl dipeptide, GMDP) for post-COVID-19 rehabilitation in patients. Material and methods. Patients who recovered from mild to moderate COVID-19 (n=60, mean age 54+/- 11.7 years) were randomized into the observation group (n=30, 15 men and 15 women) who received 2 courses of Licopid (1 mg twice a day) and the comparison group (n=30, 15 men and 15 women). Analysis of the phenotypic and functional characteristics of the innate immune cellular factors was carried out before the start of immunomodulatory therapy, immediately after the end of the course, and also after 6 months observations. In order to assess the quality of life of all patients, we used the SF-36 Health Status Survey and the Hospital Anxiety and Depression Scale questionnaires. Results. During assessing the effect of immunomodulatory therapy on the parameters of innate immunity of patients at the stage of rehabilitation after COVID-19, an increase in the protective cytolytic activity of CD16+ and CD8+Gr+ cells, as well as a persistent increase in TLR2, TLR4 and TLR9 expression was found, which indicates the antigen recognition recovery and presentation at the level of the monocytic link of the immune system. The use of GMDP as an immunomodulatory agent resulted in an 8-fold reduction in the frequency and severity of respiratory infections due to an increase in the total monocyte count. As a result of assessing patients' quality of life against the background of the therapy, a positive dynamic in role functioning was revealed in patients. In the general assessment of their health status, an increase in physical and mental well-being was noted during 6 months of observation. The comparison group showed no improvement in the psychoemotional state. Discussion. The study demonstrated the effectiveness of GMDP immunomodulatory therapy in correcting immunological parameters for post-COVID-19 rehabilitation in patients. The data obtained are consistent with the previously discovered ability of GMDP to restore impaired functions of phagocytic cells and induce the expression of their surface activation markers, which in turn contributes to an adequate response to pathogens. Conclusion. The study revealed that the correction of immunological parameters with the use of GMDP in COVID-19 convalescents contributed not only to a decrease in the frequency and severity of respiratory infections, but also to an improvement in the psycho-emotional state of patients, and a decrease in anxiety and depression.Copyright © Eco-Vector, 2023. All rights reserved.

Interaction between target peptide and complementary peptide by bimolecular fluorescence complementary technology

[Objective] Using the bimolecular fluorescence complementation (BiFC) technology, the present experiment aimed to study the interaction relationship and localization of the target peptide and the complementary peptide based on the porcine epidemic diarrhea virus (PEDV) S protein receptor binding site peptide in living cells, so as to provide the foundation and theoretical support for the further use of the peptide in the detection of porcine epidemic diarrhea virus. [Method] The target peptide was designed according to the physical and chemical characteristics of the target protein, such as the amino acid composition, the type of charge, the ability to form intennolecular hydrogen bonds, the strength of polarity, and hydrophobicity;According to the amino acid composition of the target protein, a complementary peptide that interacted with it in theory was designed, and the target peptide and complementary peptide were predicted and analyzed by using bioinfonnatics tools;The target peptide and complementary peptide were inserted into the pBiFC-VC155 and pBiFC-VN173 vector, which was double digested by the EcoRI/XhoI and NotI/SalI, respectively, verified by enzyme digestion and sequencing, and then transfected into Vero cells to study the interaction between the target peptide and the complementary peptide, and the precise localization of BiFC complex in cells. [Result] Bioinfonnatics analysis showed that the target peptide and complementary peptide had hydrophilic and hydrophobic domains, respectively, and the hydrophilic domains were both positively and negatively charged, which could generate electrostatic attraction. The results of enzyme digestion and sequencing showed that the pBiFC-VC155-target peptide and pBiFC-VNI73-complementary peptide plasmids were successfully constructed;Cell transfection experiments showed that the target peptide and complementary peptide could form BiFC complexes in Vcro cells after co-transfection of recombinant plasmids, indicating that they could interact with each other;Indirect immuttolluorescence assay confirmed that the BiFC complex was mainly distributed in the nucleus. [Conclusion] It was confirmed that the peptide designed based on the PEW/ S protein receptor binding site can interact with each other in living cells, demonstrating the feasibility of the peptide for detection.

On Immunological Studies at Sirius University of Science and Technology.

This short report summarizes the results of recent immunological studies performed at new Sirius University of Science and Technology. The report focuses on studying the features of the immune response to vaccination and revaccination against SARS-CoV-2, as well as on a search of potential agents to prevent infection with this virus.