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Microbial Pathogenesis Jun 2024Enterococcus faecalis is a troublesome nosocomial pathogen that acquired resistance to most available antimicrobial agents. Antivirulence agents represent an...
Enterococcus faecalis is a troublesome nosocomial pathogen that acquired resistance to most available antimicrobial agents. Antivirulence agents represent an unconventional treatment approach. Here, transcription factor decoy (TFD)-loaded cationic liposomes (TLL) were developed as an inhibitor of the Fsr quorum-sensing system and its associated virulence traits, in E. faecalis. The consensus sequence of the FsrA binding site was found conserved among 651 E. faecalis annotated genomes. The TFD was synthesized as an 82 bp DNA duplex, containing the conserved binding sequence, and loaded onto cationic liposomes. The optimum loading capacity, mean particle size, and zeta potential of the TLL were characterized. The developed TLL lacked any effect on E. faecalis growth and significantly inhibited the in vitro production of the proteolytic enzymes controlled by the Fsr system; gelatinase and serine protease, in a concentration-dependent manner. This inhibition was accompanied by a significant reduction in the transcription levels of FsrA-regulated genes (fsrB, gelE, and sprE). The developed TLL were safe as evidenced by the nonhemolytic effect on human RBCs and the negligible cytotoxicity on human skin fibroblast cells. Moreover, in the larvae infection model, TLL displayed a significant abolish in the mortality rates of Galleria mellonella larvae infected with E. faecalis. In conclusion, the developed TLL offer a new safe strategy for combating E. faecalis infection through the inhibition of quorum-sensing-mediated virulence; providing a platform for the development of similar agents to combat many other pathogens.
PubMed: 38936638
DOI: 10.1016/j.micpath.2024.106762 -
Plant, Cell & Environment Jun 2024In Chlamydomonas, the directly light-gated, plasma membrane-localized cation channels channelrhodopsins ChR1 and ChR2 are the primary photoreceptors for phototaxis....
In Chlamydomonas, the directly light-gated, plasma membrane-localized cation channels channelrhodopsins ChR1 and ChR2 are the primary photoreceptors for phototaxis. Their targeting and abundance is essential for optimal movement responses. However, our knowledge how Chlamydomonas achieves this is still at its infancy. Here we show that ChR1 internalization occurs via light-stimulated endocytosis. Prior or during endocytosis ChR1 is modified and forms high molecular mass complexes. These are the solely detectable ChR1 forms in extracellular vesicles and their abundance therein dynamically changes upon illumination. The ChR1-containing extracellular vesicles are secreted via the plasma membrane and/or the ciliary base. In line with this, ciliogenesis mutants exhibit increased ChR1 degradation rates. Further, we establish involvement of the cysteine protease CEP1, a member of the papain-type C1A subfamily. ΔCEP1-knockout strains lack light-induced ChR1 degradation, whereas ChR2 degradation was unaffected. Low light stimulates CEP1 expression, which is regulated via phototropin, a SPA1 E3 ubiquitin ligase and cyclic AMP. Further, mutant and inhibitor analyses revealed involvement of the small GTPase ARL11 and SUMOylation in ChR1 targeting to the eyespot and cilia. Our study thus defines the degradation pathway of this central photoreceptor of Chlamydomonas and identifies novel elements involved in its homoeostasis and targeting.
PubMed: 38935876
DOI: 10.1111/pce.15017 -
PloS One 2024To investigate the therapeutic effect and mechanism of sivelestat sodium on acute lung injury (AIL).
OBJECTIVE
To investigate the therapeutic effect and mechanism of sivelestat sodium on acute lung injury (AIL).
METHODS
A rat model for ALI/acute respiratory distress syndrome (ALI/ARDS) was established. Pathological examination of lung tissue was conducted to assess lung injury. Blood gas in the arteries was measured using a blood analyzer. Changes in PaO2, PaO2/FiO2, and lung wet/dry (W/D) weight ratio were carefully compared. ELISA assay was conducted to estimate cell adhesion and inflammation response. Finally, real-time reverse transcription polymerase chain reaction and western blotting assay was used to determine the activation of PI3K/AKT/mTOR pathway.
RESULTS
ARDS in vivo model was successfully constructed by LPS injection. Compared with the sham group, PaO2 and PaO2/FiO2 were significantly lower in the vehicle group, while the lung W/D ratio, the lung injury score, NE, VCAM-1, IL-8 andTNF-αwere significantly increased. After treatment with different doses of sivelestat sodium, we found PaO2, PaO2/FiO2 were prominently increased, while the lung W/D ratio, the lung injury score, NE, VCAM-1, IL-8, TNF-α levels were decreased in the dose-dependent manner. Meanwhile, compared with the vehicle group, the expression levels of Bax, PI3K, Akt and mTOR were significantly lower, and the expression of Bcl-2 was significantly higher after injection with sivelestat sodium.
CONCLUSION
Sivelestat sodium has an interventional effect on ALI in sepsis by inhibiting the PI3K/AKT/mTOR signalling pathway.
Topics: Animals; TOR Serine-Threonine Kinases; Acute Lung Injury; Signal Transduction; Proto-Oncogene Proteins c-akt; Phosphatidylinositol 3-Kinases; Rats; Male; Glycine; Sulfonamides; Rats, Sprague-Dawley; Lung; Disease Models, Animal
PubMed: 38935660
DOI: 10.1371/journal.pone.0302721 -
European Journal of Histochemistry : EJH Jun 2024Artificial light can affect eyeball development and increase myopia rate. Matrix metalloproteinase 2 (MMP-2) degrades the extracellular matrix, and induces its...
Effects of artificial light with different spectral compositions on refractive development and matrix metalloproteinase 2 and tissue inhibitor of metalloproteinases 2 expression in the sclerae of juvenile guinea pigs.
Artificial light can affect eyeball development and increase myopia rate. Matrix metalloproteinase 2 (MMP-2) degrades the extracellular matrix, and induces its remodeling, while tissue inhibitor of matrix MMP-2 (TIMP-2) inhibits active MMP-2. The present study aimed to look into how refractive development and the expression of MMP-2 and TIMP-2 in the guinea pigs' remodeled sclerae are affected by artificial light with varying spectral compositions. Three weeks old guinea pigs were randomly assigned to groups exposed to five different types of light: natural light, LED light with a low color temperature, three full spectrum artificial lights, i.e. E light (continuous spectrum in the range of ~390-780 nm), G light (a blue peak at 450 nm and a small valley 480 nm) and F light (continuous spectrum and wavelength of 400 nm below filtered). A-scan ultrasonography was used to measure the axial lengths of their eyes, every two weeks throughout the experiment. Following twelve weeks of exposure to light, the sclerae were observed by optical and transmission electron microscopy. Immunohistochemistry, Western blot and RT-qPCR were used to detect the MMP-2 and TIMP-2 protein and mRNA expression levels in the sclerae. After four, six, eight, ten, and twelve weeks of illumination, the guinea pigs in the LED and G light groups had axial lengths that were considerably longer than the animals in the natural light group while the guinea pigs in the E and F light groups had considerably shorter axial lengths than those in the LED group. Following twelve weeks of exposure to light, the expression of the scleral MMP-2 protein and mRNA were, from low to high, N group, E group, F group, G group, LED group; however, the expression of the scleral TIMP-2 protein and mRNA were, from high to low, N group, E group, F group, G group, LED group. The comparison between groups was statistically significant (p<0.01). Continuous, peaks-free or valleys-free artificial light with full-spectrum preserves remodeling of scleral extracellular matrix in guinea pigs by downregulating MMP-2 and upregulating TIMP-2, controlling eye axis elongation, and inhibiting the onset and progression of myopia.
Topics: Animals; Guinea Pigs; Matrix Metalloproteinase 2; Tissue Inhibitor of Metalloproteinase-2; Sclera; Light; Myopia; Refraction, Ocular
PubMed: 38934084
DOI: 10.4081/ejh.2024.3982 -
Archives of Rheumatology Jun 2024The objective was to assess the serum levels of secretory leukocyte protease inhibitor (SLPI) and elafin in individuals diagnosed with axial spondyloarthritis (AxSpA)...
OBJECTIVES
The objective was to assess the serum levels of secretory leukocyte protease inhibitor (SLPI) and elafin in individuals diagnosed with axial spondyloarthritis (AxSpA) and analyze their diagnostic significance and correlation with disease activity.
PATIENTS AND METHODS
The case-controlled, cross-sectional study was conducted between August 2021 and April 2023. Sixty patients diagnosed with AxSpA (n=60) were classified according to imaging results as nonradiographic AxSpA (nr-AxSpA [n=30]; 15 males, 15 females; median age: 30 years; range, 27.6 to 34.1 years) and radiographic AxSpA (r-AxSpA [n=30]; 19 males, 11 females; median age: 33 years; range, 30.6 to 38.1 years), forming two patient groups (the nr-axSpA and r-axSpA groups). A total of 30 age- and sex-matched healthy controls (16 females, 14 males; median age: 33 years; range, 29.2 to 37.1 years) were included. Demographic data, laboratory, and clinical characteristics of the participants were recorded.
RESULTS
There was no significant difference between SLPI and elafin serum levels in the disease groups. SLPI and elafin levels in AxSpA and nr-AxSpA groups were significantly higher compared to the control group (p<0.05). Based on receiver operating characteristic analysis, the diagnostic values of both parameters were found to be significant in the Ax-SpA and nr-AxSpA groups (p<0.05). There was no significant correlation between serum levels of SLPI and elafin and disease activity parameters. Significant positive correlations were found between SLPI and elafin in both the nr-AxSpA (p<0.05, r=0.870) and r-AxSpA (p<0.05, r=0.725) groups.
CONCLUSION
The levels of SLPI and elafin were found to be significantly elevated in patients with AxSpA, particularly in those with nr-AxSpA, compared to the control group. Therefore, SLPI and elafin can be used as therapeutic biomarkers for the diagnosis of AxSpA and nr-AxSpA. However, no relationship was found with disease activity.
PubMed: 38933721
DOI: 10.46497/ArchRheumatol.2024.10466 -
Npj Viruses 2024The Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is an epidemic, zoonotically emerging pathogen initially reported in Saudi Arabia in 2012. MERS-CoV has the...
The Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is an epidemic, zoonotically emerging pathogen initially reported in Saudi Arabia in 2012. MERS-CoV has the potential to mutate or recombine with other coronaviruses, thus acquiring the ability to efficiently spread among humans and become pandemic. Its high mortality rate of up to 35% and the absence of effective targeted therapies call for the development of antiviral drugs for this pathogen. Since the beginning of the SARS-CoV-2 pandemic, extensive research has focused on identifying protease inhibitors for the treatment of SARS-CoV-2. Our intention was therefore to assess whether these protease inhibitors are viable options for combating MERS-CoV. To that end, we used previously established protease assays to quantify inhibition of SARS-CoV-2, MERS-CoV and other main proteases. Nirmatrelvir inhibited several of these proteases, whereas ensitrelvir was less broadly active. To simulate nirmatrelvir's clinical use against MERS-CoV and subsequent resistance development, we applied a safe, surrogate virus-based system. Using the surrogate virus, we previously selected hallmark mutations of SARS-CoV-2-M, such as T21I, M49L, S144A, E166A/K/V and L167F. In the current study, we selected a pool of MERS-CoV-M mutants, characterized the resistance and modelled the steric effect of catalytic site mutants S142G, S142R, S147Y and A171S.
PubMed: 38933182
DOI: 10.1038/s44298-024-00028-2 -
Viruses Jun 2024Viral tropism is most commonly linked to receptor use, but host cell protease use can be a notable factor in susceptibility to infection. Here we review the use of host... (Review)
Review
Viral tropism is most commonly linked to receptor use, but host cell protease use can be a notable factor in susceptibility to infection. Here we review the use of host cell proteases by human viruses, focusing on those with primarily respiratory tropism, particularly SARS-CoV-2. We first describe the various classes of proteases present in the respiratory tract, as well as elsewhere in the body, and incorporate the targeting of these proteases as therapeutic drugs for use in humans. Host cell proteases are also linked to the systemic spread of viruses and play important roles outside of the respiratory tract; therefore, we address how proteases affect viruses across the spectrum of infections that can occur in humans, intending to understand the extrapulmonary spread of SARS-CoV-2.
Topics: Humans; Respiratory Tract Infections; SARS-CoV-2; Peptide Hydrolases; Viral Tropism; COVID-19; Virus Diseases; Antiviral Agents; Host-Pathogen Interactions; Protease Inhibitors
PubMed: 38932275
DOI: 10.3390/v16060984 -
Viruses Jun 2024Lipids, as a fundamental cell component, play an regulating role in controlling the different cellular biological processes involved in viral infections. A notable...
BACKGROUND
Lipids, as a fundamental cell component, play an regulating role in controlling the different cellular biological processes involved in viral infections. A notable feature of coronavirus disease 2019 (COVID-19) is impaired lipid metabolism. The function of lipophagy-related genes in COVID-19 is unknown. The present study aimed to investigate biomarkers and drug targets associated with lipophagy and lipophagy-based therapeutic agents for COVID-19 through bioinformatics analysis.
METHODS
Lipophagy-related biomarkers for COVID-19 were identified using machine learning algorithms such as random forest, Support Vector Machine-Recursive Feature Elimination, Generalized Linear Model, and Extreme Gradient Boosting in three COVID-19-associated GEO datasets: scRNA-seq (GSE145926) and bulk RNA-seq (GSE183533 and GSE190496). The cMAP database was searched for potential COVID-19 medications.
RESULTS
The lipophagy pathway was downregulated, and the lipid droplet formation pathway was upregulated, resulting in impaired lipid metabolism. Seven lipophagy-related genes, including , , , , , , and , were used as biomarkers and drug targets for COVID-19. Moreover, lipophagy may play a role in COVID-19 pathogenesis. As prospective drugs for treating COVID-19, seven potential downregulators (phenoxybenzamine, helveticoside, lanatoside C, geldanamycin, loperamide, pioglitazone, and trichostatin A) were discovered. These medication candidates showed remarkable binding energies against the seven biomarkers.
CONCLUSIONS
The lipophagy-related genes , , , , , , and can be used as biomarkers and drug targets for COVID-19. Seven potential downregulators of these seven biomarkers may have therapeutic effects for treating COVID-19.
Topics: Humans; SARS-CoV-2; COVID-19 Drug Treatment; Biomarkers; COVID-19; Lipid Metabolism; Antiviral Agents; Computational Biology; Machine Learning; Lactams, Macrocyclic; Hydroxamic Acids; Benzoquinones
PubMed: 38932215
DOI: 10.3390/v16060923 -
Viruses May 2024The emergence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has triggered a global COVID-19 pandemic, challenging healthcare systems worldwide....
The emergence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has triggered a global COVID-19 pandemic, challenging healthcare systems worldwide. Effective therapeutic strategies against this novel coronavirus remain limited, underscoring the urgent need for innovative approaches. The present research investigates the potential of cannabis compounds as therapeutic agents against SARS-CoV-2 through their interaction with the virus's papain-like protease (PLpro) protein, a crucial element in viral replication and immune evasion. Computational methods, including molecular docking and molecular dynamics (MD) simulations, were employed to screen cannabis compounds against PLpro and analyze their binding mechanisms and interaction patterns. The results showed cannabinoids with binding affinities ranging from -6.1 kcal/mol to -4.6 kcal/mol, forming interactions with PLpro. Notably, Cannabigerolic and Cannabidiolic acids exhibited strong binding contacts with critical residues in PLpro's active region, indicating their potential as viral replication inhibitors. MD simulations revealed the dynamic behavior of cannabinoid-PLpro complexes, highlighting stable binding conformations and conformational changes over time. These findings shed light on the mechanisms underlying cannabis interaction with SARS-CoV-2 PLpro, aiding in the rational design of antiviral therapies. Future research will focus on experimental validation, optimizing binding affinity and selectivity, and preclinical assessments to develop effective treatments against COVID-19.
Topics: Molecular Dynamics Simulation; SARS-CoV-2; Cannabinoids; Molecular Docking Simulation; Humans; Antiviral Agents; Coronavirus Papain-Like Proteases; Protein Binding; COVID-19 Drug Treatment; Virus Replication; Protease Inhibitors
PubMed: 38932170
DOI: 10.3390/v16060878 -
Viruses May 2024(1) Background: Geriatric patients are at high risk of complications of Coronavirus disease-2019 (COVID-19) and are good candidates for antiviral drugs. (2) Methods: A...
(1) Background: Geriatric patients are at high risk of complications of Coronavirus disease-2019 (COVID-19) and are good candidates for antiviral drugs. (2) Methods: A retrospective study of electronic health records (EHRs) aiming to describe antiviral (nirmatrelvir and ritonavir (nirmatrelvir/r) or remdesivir) use, drug-drug interactions (DDIs) and adverse drug reactions (ADRs) in elderly patients (75 and over), hospitalized with mild-to-moderate COVID-19 between July 2022 and June 2023. (3) Results: Out of 491 patients (mean age: 86.9 years), 180 (36.7%) received nirmatrelvir/r, 78 (15.9%) received remdesivir, and 233 (47.4%) received no antiviral therapy. No association was found between the choice of antiviral and the demographic or medical data. No serious ADR was observed. Nirmatrelvir/r dosage adjustment was inadequate in 65% of patients with renal impairment. In total, 128 patients (71%) on nirmatrelvir/r had potential pharmacokinetic DDIs, with 43 resulting in a possibly related ADR. In the remdesivir group, pharmacodynamic DDIs were more frequent, with QTc prolongation risk in 56 patients (72%). Only 20 patients underwent follow-up ECG, revealing QTc prolongation in 4. (4) Conclusions: There is an underutilization of antivirals despite their justified indications. Nirmatrelvir/r dosage was rarely adjusted to renal function. Dose adjustments and closer monitoring are needed due to the high risk of drug interactions.
Topics: Humans; Antiviral Agents; Female; Male; Aged, 80 and over; Retrospective Studies; COVID-19 Drug Treatment; Alanine; Adenosine Monophosphate; SARS-CoV-2; Aged; Ritonavir; Drug Interactions; COVID-19; Adenosine
PubMed: 38932157
DOI: 10.3390/v16060864