The SARS-CoV2 envelope differs from host cells, exposes procoagulant lipids, and is disrupted in vivo by oral rinses

Neurotensin accelerates atherosclerosis and increases circulating levels of short-chain and saturated triglycerides

BACKGROUND AND AIMS

Obesity and type 2 diabetes are significant risk factors for atherosclerotic cardiovascular disease (CVD) worldwide, but the underlying pathophysiological links are poorly understood. Neurotensin (NT), a 13-amino-acid hormone peptide, facilitates intestinal fat absorption and contributes to obesity in mice fed a high-fat diet. Elevated levels of pro-NT (a stable NT precursor produced in equimolar amounts relative to NT) are associated with obesity, type 2 diabetes, and CVD in humans. Whether NT is a causative factor in CVD is unknown.

METHODS

Nt+/+ and Nt-/- mice were either injected with adeno-associated virus encoding PCSK9 mutants or crossed with Ldlr-/- mice and fed a Western diet. Atherosclerotic plaques were analyzed by en face analysis, Oil Red O and CD68 staining. In humans, we evaluated the association between baseline pro-NT and growth of carotid bulb thickness after 16.4 years. Lipidomic profiles were analyzed.

RESULTS

Atherosclerotic plaque formation is attenuated in Nt-deficient mice through mechanisms that are independent of reductions in circulating cholesterol and triglycerides but associated with remodeling of the plasma triglyceride pool. An increasing plasma concentration of pro-NT predicts atherosclerotic events in coronary and cerebral arteries independent of all major traditional risk factors, indicating a strong link between NT and atherosclerosis. This plasma lipid profile analysis confirms the association of pro-NT with remodeling of the plasma triglyceride pool in atherosclerotic events.

CONCLUSIONS

Our findings are the first to directly link NT to increased atherosclerosis and indicate the potential role for NT in preventive and therapeutic strategies for CVD.

Uncovering the Effect of SARS-CoV-2 on Liver Metabolism via Genome-Scale Metabolic Modeling for Reprogramming and Therapeutic Strategies

Genome-scale metabolic models (GEMs) are promising computational tools that contribute to elucidating host-virus interactions at the system level and developing therapeutic strategies against viral infection. In this study, the effect of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on liver metabolism was investigated using integrated GEMs of human hepatocytes and SARS-CoV-2. They were generated for uninfected and infected hepatocytes using transcriptome data. Reporter metabolite analysis resulted in significant transcriptional changes around several metabolites involved in xenobiotics, drugs, arachidonic acid, and leukotriene metabolisms due to SARS-CoV-2 infection. Flux balance analysis and minimization of metabolic adjustment approaches unraveled possible virus-induced hepatocellular reprogramming in fatty acid, glycerophospholipid, sphingolipid cholesterol, and folate metabolisms, bile acid biosynthesis, and carnitine shuttle among others. Reaction knockout analysis provided critical reactions in glycolysis, oxidative phosphorylation, purine metabolism, and reactive oxygen species detoxification subsystems. Computational analysis also showed that administration of dopamine, glucosamine, D-xylose, cysteine, and (R)-3-hydroxybutanoate contributes to alleviating viral infection. In essence, the reconstructed host-virus GEM helps us understand metabolic programming and develop therapeutic strategies to battle SARS-CoV-2.

Interaction of Methylene Blue with Severe Acute Respiratory Syndrome Coronavirus 2 Envelope Revealed by Molecular Modeling

Methylene blue has multiple antiviral properties against Severe Acute Respiratory Syndrome-related Coronavirus 2 (SARS-CoV-2). The ability of methylene blue to inhibit different stages of the virus life cycle, both in light-independent and photodynamic processes, is used in clinical practice. At the same time, the molecular aspects of the interactions of methylene blue with molecular components of coronaviruses are not fully understood. Here, we use Brownian dynamics to identify methylene blue binding sites on the SARS-CoV-2 envelope. The local lipid and protein composition of the coronavirus envelope plays a crucial role in the binding of this cationic dye. Viral structures targeted by methylene blue include the S and E proteins and negatively charged lipids. We compare the obtained results with known experimental data on the antiviral effects of methylene blue to elucidate the molecular basis of its activity against coronaviruses.

Learning from COVID-19: How drug hunters can prepare for the next pandemic

Over 3 years, the SARS-CoV-2 pandemic killed nearly 7 million people and infected more than 767 million globally. During this time, our very small company was able to contribute to antiviral drug discovery efforts through global collaborations with other researchers, which enabled the identification and repurposing of multiple molecules with activity against SARS-CoV-2 including pyronaridine tetraphosphate, tilorone, quinacrine, vandetanib, lumefantrine, cetylpyridinium chloride, raloxifene, carvedilol, olmutinib, dacomitinib, crizotinib, and bosutinib. We highlight some of the key findings from this experience of using different computational and experimental strategies, and detail some of the challenges and strategies for how we might better prepare for the next pandemic so that potential antiviral treatments are available for future outbreaks.

Interaction of SARS-CoV-2 with host cells and antibodies: experiment and simulation

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the devastating global COVID-19 pandemic announced by WHO in March 2020. Through unprecedented scientific effort, several vaccines, drugs and antibodies have been developed, saving millions of lives, but the fight against COVID-19 continues as immune escape variants of concern such as Delta and Omicron emerge. To develop more effective treatments and to elucidate the side effects caused by vaccines and therapeutic agents, a deeper understanding of the molecular interactions of SARS-CoV-2 with them and human cells is required. With special interest in computational approaches, we will focus on the structure of SARS-CoV-2 and the interaction of its spike protein with human angiotensin-converting enzyme-2 (ACE2) as a prime entry point of the virus into host cells. In addition, other possible viral receptors will be considered. The fusion of viral and human membranes and the interaction of the spike protein with antibodies and nanobodies will be discussed, as well as the effect of SARS-CoV-2 on protein synthesis in host cells.

Characterization of the cellular lipid composition during SARS-CoV-2 infection

Emerging and re-emerging zoonotic viral diseases continue to significantly impact public health. Of particular interest are enveloped viruses (e.g., SARS-CoV-2, the causative pathogen of COVID-19), which include emerging pathogens of highest concern. Enveloped viruses contain a viral envelope that encapsulates the genetic material and nucleocapsid, providing structural protection and functional bioactivity. The viral envelope is composed of a coordinated network of glycoproteins and lipids. The lipid composition of the envelope consists of lipids preferentially appropriated from host cell membranes. Subsequently, changes to the host cell lipid metabolism and an accounting of what lipids are changed during viral infection provide an opportunity to fingerprint the host cell's response to the infecting virus. To address this issue, we comprehensively characterized the lipid composition of VeroE6-TMPRSS2 cells infected with SARS-CoV-2. Our approach involved using an innovative solid-phase extraction technique to efficiently extract cellular lipids combined with liquid chromatography coupled to high-resolution tandem mass spectrometry. We identified lipid changes in cells exposed to SARS-CoV-2, of which the ceramide to sphingomyelin ratio was most prominent. The identification of a lipid profile (i.e., lipid fingerprint) that is characteristic of cellular SARS-CoV-2 infection lays the foundation for targeting lipid metabolism pathways to further understand how enveloped viruses infect cells, identifying opportunities to aid antiviral and vaccine development.

Antiviral efficacy of nanomaterial-treated textiles in real-life like exposure conditions

Due to the growing interest towards reducing the number of potentially infectious agents on critical high-touch surfaces, the popularity of antimicrobially and antivirally active surfaces, including textiles, has increased. The goal of this study was to create antiviral textiles by spray-depositing three different nanomaterials, two types of CeO2 nanoparticles and quaternary ammonium surfactant CTAB loaded SiO2 nanocontainers, onto the surface of a knitted polyester textile and assess their antiviral activity against two coronaviruses, porcine transmissible gastroenteritis virus (TGEV) and severe acute respiratory syndrome virus (SARS CoV-2). Antiviral testing was carried out in small droplets in semi-dry conditions and in the presence of organic soiling, to mimic aerosol deposition of viruses onto the textiles. In such conditions, SARS CoV-2 stayed infectious at least for 24 h and TGEV infected cells even after 72h of semi-dry deposition suggesting that textiles exhibiting sufficient antiviral activity before or at 24 h, can be considered promising. The antiviral efficacy of nanomaterial-deposited textiles was compared with the activity of the same nanomaterials in colloidal form and with positive control textiles loaded with copper nitrate and CTAB. Our results indicated that after deposition onto the textile, CeO2 nanoparticles lost most of their antiviral activity, but antiviral efficacy of CTAB-loaded SiO2 nanocontainers was retained also after deposition. Copper nitrate deposited textile that was used as a positive control, showed relatively high antiviral activity as expected. However, as copper was effectively washed away from the textile already during 1 h, the use of copper for creating antiviral textiles would be impractical. In summary, our results indicated that antiviral activity of textiles cannot be predicted from antiviral efficacy of the deposited compounds in colloid and attention should be paid on prolonged efficacy of antivirally coated textiles.

Discovery of PLpro and Mpro Inhibitors for SARS-CoV-2

There are very few small-molecule antivirals for SARS-CoV-2 that are either currently approved (or emergency authorized) in the US or globally, including remdesivir, molnupiravir, and paxlovid. The increasing number of SARS-CoV-2 variants that have appeared since the outbreak began over three years ago raises the need for continual development of updated vaccines and orally available antivirals in order to fully protect or treat the population. The viral main protease (Mpro) and the papain-like protease (PLpro) are key for viral replication; therefore, they represent valuable targets for antiviral therapy. We herein describe an in vitro screen performed using the 2560 compounds from the Microsource Spectrum library against Mpro and PLpro in an attempt to identify additional small-molecule hits that could be repurposed for SARS-CoV-2. We subsequently identified 2 hits for Mpro and 8 hits for PLpro. One of these hits was the quaternary ammonium compound cetylpyridinium chloride with dual activity (IC50 = 2.72 ± 0.09 μM for PLpro and IC50 = 7.25 ± 0.15 μM for Mpro). A second inhibitor of PLpro was the selective estrogen receptor modulator raloxifene (IC50 = 3.28 ± 0.29 μM for PLpro and IC50 = 42.8 ± 6.7 μM for Mpro). We additionally tested several kinase inhibitors and identified olmutinib (IC50 = 0.54 ± 0.04 μM), bosutinib (IC50 = 4.23 ± 0.28 μM), crizotinib (IC50 = 3.81 ± 0.04 μM), and dacominitinib (IC50 = IC50 3.33 ± 0.06 μM) as PLpro inhibitors for the first time. In some cases, these molecules have also been tested by others for antiviral activity for this virus, or we have used Calu-3 cells infected with SARS-CoV-2. The results suggest that approved drugs can be identified with promising activity against these proteases, and in several cases we or others have validated their antiviral activity. The additional identification of known kinase inhibitors as molecules targeting PLpro may provide new repurposing opportunities or starting points for chemical optimization.

Deficiency in the production of antibodies to lipids correlates with increased lipid metabolism in severe COVID-19 patients

Background

Antibodies to lipids are part of the first line of defense against microorganisms and regulate the pro/anti-inflammatory balance. Viruses modulate cellular lipid metabolism to enhance their replication, and some of these metabolites are proinflammatory. We hypothesized that antibodies to lipids would play a main role of in the defense against SARS-CoV-2 and thus, they would also avoid the hyperinflammation, a main problem in severe condition patients.

Methods

Serum samples from COVID-19 patients with mild and severe course, and control group were included. IgG and IgM to different glycerophospholipids and sphingolipids were analyzed using a high-sensitive ELISA developed in our laboratory. A lipidomic approach for studying lipid metabolism was performed using ultra-high performance liquid chromatography coupled to electrospray ionization and quadrupole time-of-flight mass spectrometry (UHPLC-ESI-QTOF-MS).

Results

Mild and severe COVID-19 patients had higher levels of IgM to glycerophosphocholines than control group. Mild COVID-19 patients showed higher levels of IgM to glycerophosphoinositol, glycerophosphoserine and sulfatides than control group and mild cases. 82.5% of mild COVID-19 patients showed IgM to glycerophosphoinositol or glycerophosphocholines plus sulfatides or glycerophosphoserines. Only 35% of severe cases and 27.5% of control group were positive for IgM to these lipids. Lipidomic analysis identify a total of 196 lipids, including 172 glycerophospholipids and 24 sphingomyelins. Increased levels of lipid subclasses belonging to lysoglycerophospholipids, ether and/or vinyl-ether-linked glycerophospholipids, and sphingomyelins were observed in severe COVID-19 patients, when compared with those of mild cases and control group.

Conclusion

Antibodies to lipids are essential for defense against SARS-CoV-2. Patients with low levels of anti-lipid antibodies have an elevated inflammatory response mediated by lysoglycerophospholipids. These findings provide novel prognostic biomarkers and therapeutic targets.

Preprocedural Viral Load Effects of Oral Antiseptics on SARS-CoV-2 in Patients with COVID-19: A Systematic Review

(1) There are limited clinical trials to support the effectiveness of mouth rinses when used as a preprocedural rinse against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This systematic review aims to evaluate the efficacy of antiseptic mouth rinses as a preprocedural rinse in reducing SARS-CoV-2 oral viral load in-vivo. (2) Methods: A literature search was conducted through November 2022 for the following databases: PubMed, Web of Science, Cochrane Library, and Google Scholar. The evaluated outcomes were quantitative changes in viral load and the statistical significance of that change after using antiseptic mouth rinses. (3) Results: 14 randomized controlled trials (RCT) were selected for risk of bias assessment and data extraction. (4) Conclusion: Within the limits of this systematic review, preprocedural mouth rinses may significantly reduce SARS-CoV-2 in the mouth, thus, reducing the viral particles available for airborne dispersion. Preprocedural mouth rinses may be an effective strategy for reducing airborne SARS-CoV-2 dispersion in the environment. Their use may be a preventive strategy to reduce the spread of COVID-19 in selected medical and healthcare facilities, including dental clinics. Potential preprocedural mouth rinses are identified for use as an integral part of safe practice for healthcare protocols. This systematic review was registered with the National Institute for Health Research, international prospective register of systematic reviews (PROSPERO): CRD42022315177.

Enhanced in vitro antibacterial effect against Enterococcus faecalis by using both low-dose cetylpyridinium chloride and silver ions

BACKGROUND

Enterococcus faecalis (E. faecalis) is frequently isolated from root canals with failed root canal treatments. Due to the strong ability of E. faecalis to resist many often-used antimicrobials, coping with E. faecalis infections remains a challenge. The aim of this study was to investigate the synergistic antibacterial effect of low-dose cetylpyridinium chloride (CPC) and silver ions (Ag⁺) against E. faecalis in vitro.

METHODS

The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and the fractional inhibitory concentration index (FICI) were used to confirm the existence of the synergic antibacterial activity between low-dose CPC and Ag⁺. Colony-forming unit (CFU) counting, time-killing curve and dynamic growth curve were used to evaluate the antimicrobial effects of CPC and Ag⁺ combinations against planktonic E. faecalis. Four weeks biofilms were treated with drug-contained gels to determine the antimicrobial effect on biofilm-resident E.faecalis, and the integrity of E.faecalis and its biofilms were observed by FE-SEM. CCK-8 assays was used to test the cytotoxicity of CPC and Ag⁺ combinations on MC3T3-E1 cells.

RESULTS

The results confirmed the synergistic antibacterial effect of low-dose CPC and Ag⁺ against both planktonic and 4-week biofilm E. faecalis. After the addition of CPC, the sensitivity of both planktonic and biofilm-resident E. faecalis to Ag⁺ improved, and the combination showed good biocompatibility on MC3T3-E1 cells.

CONCLUSIONS

Low-dose CPC enhanced the antibacterial ability of Ag⁺ against both planktonic and biofilm E.faecalis with good biocompatibility. It may be developed into a novel and potent antibacterial agent against E.faecalis, with low toxicity for root canal disinfection or other related medical applications.

Current SARS-CoV-2 Protective Strategies for Healthcare Professionals

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for the Coronavirus disease 2019 (COVID-19). COVID-19 was first reported in China in December 2019. SARS-CoV-2 is highly contagious and spread primarily via an airborne route. Hand hygiene, surgical masks, vaccinations and boosters, air filtration, environmental sanitization, instrument sterilization, mouth rinses, and social distancing are essential infection control measures against the transmission of SARS-CoV-2. This paper aims to provide healthcare professionals with evidence-based protective strategies.

Integrative network pharmacology and in silico analyses identify the anti-omicron SARS-CoV-2 potential of eugenol

Eugenol as a natural product is the source of isoniazid, and purified eugenol is extensively used in the cosmetics industry and the productive processes of edible spices. Accumulating evidence suggested that eugenol exerted potent anti-microorganism and anti-inflammation effects. Application of eugenol effectively reduced the risk of atherosclerosis, arterial embolism, and Type 2 diabetes. A previous study confirmed that treatment with eugenol attenuated lung inflammation and improved heart functions in SARS-CoV-2 spike S1-intoxicated mice. In addition to the study, based on a series of public datasets, computational analyses were conducted to characterize the acting targets of eugenol and the functional roles of these targets in COVID-19. The binding capacities of eugenol to conservative sites of SARS-CoV-2 like RNA-dependent RNA polymerase (RdRp) and mutable site as spike (S) protein, were calculated by using molecular docking following the molecular dynamics simulation with RMSD, RMSF, and MM-GBSA methods. The results of network pharmacology indicated that six targets, including PLAT, HMOX1, NUP88, CTSL, ITGB1 andTMPRSS2 were eugenol-SARS-CoV-2 interacting proteins. The omics results of in-silico study further implicated that eugenol increased the expression of SCARB1, HMOX1 and GDF15, especially HMOX1, which were confirmed the potential interacting targets between eugenol and SARS-CoV-2 antigens. Enrichment analyses indicated that eugenol exerted extensive biological effects such as regulating immune infiltration of macrophage, lipid localization, monooxyenase activity, iron ion binding and PPAR signaling. The results of the integrated analysis of eugenol targets and immunotranscription profile of COVID-19 cases shows that eugenol also plays an important role in strengthen of immunologic functions and regulating cytokine signaling. As a complement to the integrated analysis, the results of molecular docking indicated the potential binding interactions between eugenol and four proteins relating to cytokine production/release and the function of T type lymphocytes, including human TLR-4, TCR, NF-κB, JNK and AP-1. Furthermore, results of molecular docking and molecular dynamics (100ns) simulations implicated that stimulated modification of eugenol to the SARS-CoV-2 Omicron Spike-ACE2 complex, especially for human ACE2, and the molecular interaction of eugenol to SARS-CoV-2 RdRp, were no less favorable than two positive controls, molnupiravir and nilotinib. Dynamics (200ns) simulations indicated that the binding capacities and stabilities of eugenol to finger subdomain of RdRp is no less than molnupiravir. However, the simulated binding capacity of eugenol to SARS-CoV-2 wild type RBD and Omicron mutant RBD were less than nilotinib. Eugenol was predicted to have more favor LD50 value and lower cytotoxicity than two positive controls, and eugenol can pass through the blood-brain barrier (BBB). In a brief, eugenol is helpful for attenuating systemic inflammation induced by SARS-CoV-2 infection, due to the direct interaction of eugenol to SARS-CoV-2 proteins and extensive bio-manipulation of pro-inflammatory factors. This study carefully suggests eugenol is a candidate compound of developing drugs and supplement agents against SARS-CoV-2 and its Omicron variants.

Efficacy of Cetylpyridinium Chloride mouthwash against SARS-CoV-2: A systematic review of randomized controlled trials

INTRODUCTION

COVID-19 is a transmissible respiratory and multisystem disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Viral transmission occurs mainly through the spread of salivary droplets or aerosol from an infected subject. Studies suggest that salivary viral load is correlated with disease severity and probability of transmission. Cetylpyridinium chloride mouthwash has been found to be effective in reducing salivary viral load. The aim of this systematic review of randomized controlled trials is to evaluate the efficacy of the mouthwash ingredient cetylpyridinium chloride on salivary viral load in SARS-CoV-2 infection.

METHODS

Randomized controlled trials comparing cetylpyridinium chloride mouthwash with placebo and other mouthwash ingredients in SARS-CoV-2 positive individuals were identified and evaluated.

RESULTS

Six studies with a total of 301 patients that met the inclusion criteria were included. The studies reported the efficacy of cetylpyridinium chloride mouthwashes in reduction on SARS-CoV-2 salivary viral load compared to placebo and other mouthwash ingredients.

CONCLUSION

Mouthwashes containing cetylpyridinium chloride are effective against salivary viral load of SARS-CoV-2 in vivo. There is also the possibility that the use of mouthwash containing cetylpyridinium chloride in SARS-CoV-2 positive subjects could reduce transmissibility and severity of COVID-19.

Guiding the choice of informatics software and tools for lipidomics research applications

Progress in mass spectrometry lipidomics has led to a rapid proliferation of studies across biology and biomedicine. These generate extremely large raw datasets requiring sophisticated solutions to support automated data processing. To address this, numerous software tools have been developed and tailored for specific tasks. However, for researchers, deciding which approach best suits their application relies on ad hoc testing, which is inefficient and time consuming. Here we first review the data processing pipeline, summarizing the scope of available tools. Next, to support researchers, LIPID MAPS provides an interactive online portal listing open-access tools with a graphical user interface. This guides users towards appropriate solutions within major areas in data processing, including (1) lipid-oriented databases, (2) mass spectrometry data repositories, (3) analysis of targeted lipidomics datasets, (4) lipid identification and (5) quantification from untargeted lipidomics datasets, (6) statistical analysis and visualization, and (7) data integration solutions. Detailed descriptions of functions and requirements are provided to guide customized data analysis workflows.

A Mechanism of Double-Membrane Vesicle Formation from Liquid-Ordered/Liquid-Disordered Phase Separated Spherical Membrane

Genome replication of coronaviruses takes place in specific cellular compartments, in so-called double-membrane vesicles (DMVs), formed from the endoplasmic reticulum (ER). An intensive production of DMVs is induced by non-structural viral proteins. Here, we proposed a possible mechanism of the DMV formation from ER-derived spherical vesicles where liquid-ordered and liquid-disordered lipid phases coexist. These vesicles are supposed to divide into two homogeneous liquid-ordered and liquid-disordered vesicles. The formation of two spherical vesicles constituting DMV requires a mechanical work to be performed. We considered the excess energy of the boundary between the coexisting lipid phases as the main driving force behind the division of the initial vesicle. Explicitly accounting for the energy of elastic deformations and the interphase boundary energy, we analyzed a range of physical parameters where the DMV formation is possible. We concluded that this process can principally take place in a very narrow range of system parameters. The most probable diameter of DMVs formed according to the proposed mechanism appeared to be approximately 220 nm, in an agreement with the average diameter of DMVs observed in vivo. Our consideration predicts the DMV size to be strongly limited from above. The developed analysis can be utilized for the production of DMVs in model systems.

Interaction of GC376, a SARS-COV-2 MPRO inhibitor, with model lipid membranes

Partitioning and effect of antiviral GC376, a potential SARS-CoV-2 inhibitor, on model lipid membranes was studied using dynamic light scattering (DLS), UV–VIS spectrometry, Excimer fluorescence, Differential scanning calorimetry (DSC) and Small- and Wide-angle X-ray scattering (SAXS/WAXS). Partition coefficient of GC376 between lipid and water phase was found to be low, reaching K_P = 46.8 ± 18.2. Results suggest that GC376 partitions into lipid bilayers at the level of lipid head-groups, close to the polar/hydrophobic interface. Changes in structural and thermodynamic properties strongly depend on the GC376/lipid mole ratio. Already at lowest mole ratios GC376 induces increase of lateral pressures, mainly in the interfacial region of the bilayer. Hereby, the pre- and main-transition temperature of the lipid system increases, what is attributed to tighter packing of acyl chains induced by GC376. At GC376/DPPC ≥ 0.03 mol/mol we detected formation of domains with different GC376 content resulting in the lateral phase separation and changes in both, main transition temperature and enthalpy. The observed changes are attributed to the response of the system on the increased lateral stresses induced by partitioning of GC376. Obtained results are discussed in context of liposome-based drug delivery systems for GC376 and in context of indirect mechanism of virus replication inhibition.

Dynamic modulations of urinary sphingolipid and glycerophospholipid levels in COVID-19 and correlations with COVID-19-associated kidney injuries

Background

Among various complications of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), renal complications, namely COVID-19-associated kidney injuries, are related to the mortality of COVID-19.

Methods

In this retrospective cross-sectional study, we measured the sphingolipids and glycerophospholipids, which have been shown to possess potent biological properties, using liquid chromatography-mass spectrometry in 272 urine samples collected longitudinally from 91 COVID-19 subjects and 95 control subjects without infectious diseases, to elucidate the pathogenesis of COVID-19-associated kidney injuries.

Results

The urinary levels of C18:0, C18:1, C22:0, and C24:0 ceramides, sphingosine, dihydrosphingosine, phosphatidylcholine, lysophosphatidylcholine, lysophosphatidic acid, and phosphatidylglycerol decreased, while those of phosphatidylserine, lysophosphatidylserine, phosphatidylethanolamine, and lysophosphatidylethanolamine increased in patients with mild COVID-19, especially during the early phase (day 1–3), suggesting that these modulations might reflect the direct effects of infection with SARS-CoV-2. Generally, the urinary levels of sphingomyelin, ceramides, sphingosine, dihydrosphingosine, dihydrosphingosine l-phosphate, phosphatidylcholine, lysophosphatidic acid, phosphatidylserine, lysophosphatidylserine, phosphatidylethanolamine, lysophosphatidylethanolamine, phosphatidylglycerol, lysophosphatidylglycerol, phosphatidylinositol, and lysophosphatidylinositol increased, especially in patients with severe COVID-19 during the later phase, suggesting that their modulations might result from kidney injuries accompanying severe COVID-19.

Conclusions

Considering the biological properties of sphingolipids and glycerophospholipids, an understanding of their urinary modulations in COVID-19 will help us to understand the mechanisms causing COVID-19-associated kidney injuries as well as general acute kidney injuries and may prompt researchers to develop laboratory tests for predicting maximum severity and/or novel reagents to suppress the renal complications of COVID-19.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12929-022-00880-5.

Dynamic modulations of sphingolipids and glycerophospholipids in COVID-19

BACKGROUND

A heterogeneous clinical phenotype is a characteristic of coronavirus disease 2019 (COVID-19). Therefore, investigating biomarkers associated with disease severity is important for understanding the mechanisms responsible for this heterogeneity and for developing novel agents to prevent critical conditions. This study aimed to elucidate the modulations of sphingolipids and glycerophospholipids, which have been shown to possess potent biological properties.

METHODS

We measured the serum sphingolipid and glycerophospholipid levels in a total of 887 samples from 215 COVID-19 subjects, plus 115 control subjects without infectious diseases and 109 subjects with infectious diseases other than COVID-19.

RESULTS

We observed the dynamic modulations of sphingolipids and glycerophospholipids in the serum of COVID-19 subjects, depending on the time course and severity. The elevation of C16:0 ceramide and lysophosphatidylinositol and decreases in C18:1 ceramide, dihydrosphingosine, lysophosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol were specific to COVID-19. Regarding the association with maximum severity, phosphatidylinositol and phosphatidylcholine species with long unsaturated acyl chains were negatively associated, while lysophosphatidylethanolamine and phosphatidylethanolamine were positively associated with maximum severity during the early phase. Lysophosphatidylcholine and phosphatidylcholine had strong negative correlations with CRP, while phosphatidylethanolamine had strong positive ones. C16:0 ceramide, lysophosphatidylcholine, phosphatidylcholine and phosphatidylethanolamine species with long unsaturated acyl chains had negative correlations with D-dimer, while phosphatidylethanolamine species with short acyl chains and phosphatidylinositol had positive ones. Several species of phosphatidylcholine, phosphatidylethanolamine and sphingomyelin might serve as better biomarkers for predicting severe COVID-19 during the early phase than CRP and D-dimer. Compared with the lipid modulations seen in mice treated with lipopolysaccharide, tissue factor, or histone, the lipid modulations observed in severe COVID-19 were most akin to those in mice administered lipopolysaccharide.

CONCLUSION

A better understanding of the disturbances in sphingolipids and glycerophospholipids observed in this study will prompt further investigation to develop laboratory testing for predicting maximum severity and/or novel agents to suppress the aggravation of COVID-19.

Disinfection and decontamination in the context of SARS-CoV-2-specific data

Given the high transmissibility of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as witnessed early in the coronavirus disease 2019 (COVID-19) pandemic, concerns arose with the existing methods for virus disinfection and decontamination. The need for SARS-CoV-2-specific data stimulated considerable research in this regard. Overall, SARS-CoV-2 is practically and equally susceptible to approaches for disinfection and decontamination that have been previously found for other human or animal coronaviruses. The latter have included techniques utilizing temperature modulation, pH extremes, irradiation, and chemical treatments. These physicochemical methods are a necessary adjunct to other prevention strategies, given the environmental and patient surface ubiquity of the virus. Classic studies of disinfection have also allowed for extrapolation to the eradication of the virus on human mucosal surfaces by some chemical means. Despite considerable laboratory study, practical field assessments are generally lacking and need to be encouraged to confirm the correlation of interventions with viral eradication and infection prevention. Transparency in the constitution and use of any method or chemical is also essential to furthering practical applications.

Efficacy of Mouth Rinses and Nasal Spray in the Inactivation of SARS-CoV-2: A Systematic Review and Meta-Analysis of In Vitro and In Vivo Studies

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) is a global and evolving pandemic associated with heavy health and financial burdens. Considering the oral cavity as the major reservoir for SARS-CoV-2, a systematic review and meta-analysis were conducted to assess the efficacy of mouth rinses and nasal sprays in reducing the salivary viral load of SARS-CoV-2. All in vivo and in vitro studies that assessed the virucidal efficacy of mouth rinses and nasal sprays against SARS-CoV-2 and were published in the English language from December 2019 to April 2022 were considered for analyses. Special Medical Subject Headings terms were used to search Pubmed, Scopus, Embase Ovid, and Web of Science databases. The toxicological data reliability assessment tool (ToxRToool) was used to assess the quality of the included studies. Thirty-three studies (11 in vivo and 22 in vitro) were deemed eligible for inclusion in this analysis. Results of the pooled data showed that povidone-iodine is the most efficacious intervention in vivo in terms of reducing the SARS-CoV-2 salivary viral load, followed by chlorhexidine. The mean difference in the viral load was 86% and 72%, respectively. Similarly, povidone-iodine was associated with the highest log₁₀ reduction value (LRV) in vitro, followed by cetylpyridinium chloride, (LRV = 2.938 (p < 0.0005) and LRV = 2.907 (p = 0.009), respectively). Povidone-iodine-based oral and nasal preparations showed favourable results in terms of reducing SARS-CoV-2 viral loads both in vivo and in vitro. Considering the limited number of patients in vivo, further studies among larger cohorts are recommended.

Mechanically Ventilated Patients Shed High-Titer Live Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) for Extended Periods From Both the Upper and Lower Respiratory Tract

BACKGROUND

SARS-CoV-2 infection can lead to severe acute respiratory distress syndrome needing intensive care admission and may lead to death. As a virus that transmits by respiratory droplets and aerosols, determining the duration of viable virus shedding from the respiratory tract is critical for patient prognosis, and informs infection-control measures both within healthcare settings and the public domain.

METHODS

We prospectively examined upper and lower airway respiratory secretions for both viral RNA and infectious virions in mechanically ventilated patients admitted to the intensive care unit (ICU) of the University Hospital of Wales. Samples were taken from the oral cavity (saliva), oropharynx (subglottic aspirate), or lower respiratory tract (nondirected bronchoalveolar lavage [NBAL] or bronchoalveolar lavage [BAL]) and analyzed by both quantitative PCR (qPCR) and plaque assay.

RESULTS

117 samples were obtained from 25 patients. qPCR showed extremely high rates of positivity across all sample types; however, live virus was far more common in saliva (68%) than in BAL/NBAL (32%). Average titers of live virus were higher in subglottic aspirates (4.5 × 107) than in saliva (2.2 × 106) or BAL/NBAL (8.5 × 106) and reached >108 PFU/mL in some samples. The longest duration of shedding was 98 days, while most patients (14/25) shed live virus for ≥20 days.

CONCLUSIONS

ICU patients infected with SARS-CoV-2 can shed high titers of virus both in the upper and lower respiratory tract and tend to be prolonged shedders. This information is important for decision making around cohorting patients, de-escalation of personal protective equipment, and undertaking potential aerosol-generating procedures.