A steroid-mimicking nanomaterial that mediates inhibition of human lung mast cell responses

Human Lung Mast Cells as a Possible Reservoir for Coronavirus: A Novel Unrecognized Mechanism for SARS-CoV-2 Immune-Mediated Pathology

The pathogenic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global health concern. Cell entry of SARS-CoV-2 depends on viral spike (S) proteins binding to cellular receptors (ACE2) and their subsequent priming by host cell proteases (TMPRSS2). Assessing effects of viral-induced host response factors and determining which cells are used by SARS-CoV-2 for entry might provide insights into viral transmission, add clarity to the virus' pathogenesis, and possibly reveal therapeutic targets. Mast cells (MCs) are ubiquitously expressed tissue cells that act as immune sentinels given their ability to react specifically to pathogens at environmental interfaces, such as in the lung. Several lines of evidence suggest a critical role for MCs in SARS-CoV-2 infections based on patients' mediator profiles, especially the "cytokine storm" responsible for most morbidity and mortality. In this pilot study, we demonstrated that human lung MCs (n = 3 donors) are a source of renin and that they upregulate the membrane receptor for SARS-CoV-2 (ACE2) as well as the protease required for cellular entry (TMPRSS2) under certain conditions. We hypothesized that infection of human MCs with SARS-CoV-2 may be a heretofore-unrecognized mechanism of viral pathogenesis, and further studies are required to assess this question.

Anti-Inflammatory and Antioxidant Effects of Liposoluble C60 at the Cellular, Molecular, and Whole-Animal Levels

Introduction

Liposoluble carbon-60 (C60) has potential applications in many fields, including cosmetics, medical devices, and medicine, but its specific mechanism of action remains unclear. This study explored whether liposoluble C60 could be delivered to human organs, tissues, and cells through blood, extracellular fluid, and cell culture fluid and whether it exerts anti-inflammatory and antioxidant effects at the molecular, cellular, and whole-animal levels.

Methods

At the cellular level, we mixed C60 dissolved in grape seed oil with cell culture medium containing 10% serum and investigated its effects on tumor necrosis factor-α (TNF-α) release, migration, phagocytosis, respiratory burst, and apoptosis in freshly isolated human neutrophils. At the molecular level, we mixed a trace amount of C60 dissolved in grape seed oil with aqueous and ethanolic solutions and studied its antioxidant effect. At the animal level, we investigated the inhibitory effect of C60 on the serum inflammatory marker C-reactive protein (CRP) in beagle dogs after oral administration of C60 dissolved in grape seed oil.

Results

The results showed that the trace amount of C60 dissolved in grape seed oil significantly inhibited TNF-α release, cell migration, phagocytosis, and respiratory burst in freshly isolated human neutrophils. In addition, the trace amount of C60 dissolved in grape seed oil had a significant scavenging effect on superoxide free radicals and 1,1-diphenyl-2-trinitrophenylhydrazine free radicals. Oral administration of C60 dissolved in grape seed oil markedly reduced the level of the serum inflammatory marker CRP in beagle dogs.

Conclusion

In summary, a trace amount of hydrophobic C60 in hydrophilic media effectively produced anti-inflammatory and antioxidant effects in cells and animals. C60 dissolved in grape seed oil is a novel anti-inflammatory and antioxidant drug candidate.

Investigating the AC079305/DUSP1 Axis as Oxidative Stress-Related Signatures and Immune Infiltration Characteristics in Ischemic Stroke

Background

Oxidative stress (OS) and immune inflammation play complex intersections in the pathophysiology of ischemic stroke (IS). However, a competing endogenous RNA- (ceRNA-) based mechanism linked to the intersections in IS has not been explored. We aimed to identify potential OS-related signatures and analyze immune infiltration characteristics in IS.

Methods

Three datasets (GSE22255, GSE110993, and GSE140275) from the GEO database were extracted. Differentially expressed long noncoding RNAs, microRNAs, and messenger RNAs (DElncRNAs, DEmiRNAs, and DEmRNAs) between IS patients and controls were identified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were explored. Moreover, a triple ceRNA network was constructed to reveal transcriptional regulation mechanisms. A comprehensive strategy among least absolute shrinkage and selection operator (LASSO) regression, DEmRNAs, uprelated DEmRNAs, and OS-related genes was adopted to select the best signature. Then, we evaluated and verified the discriminant ability of the signature via receiver operating characteristic (ROC) analysis. Immune infiltration characteristics were explored via the CIBERSORT algorithm. Moreover, the best signature was verified via qPCR and western blot methods in rat brain tissues and PC12 cells.

Results

11 DEmRNAs were identified totally. Enrichment analysis showed that the DEmRNAs were primarily concentrated in MAPK-associated biological processes and immune or inflammation-involved pathways. DUSP1 was identified as the best signature with an area under the ROC curve of 73.5% (95%CI = 57.02-89.98, sensitivity = 95%, and specificity = 60%) in GSE22255 and 100.0% (95%CI = 100.00-100.00, sensitivity = 100%, and specificity = 100%) in GSE140275. Importantly, we also identified the AC079305/DUSP1 axis in the ceRNA network. Immune infiltration showed that resting mast cells infiltrate less in IS patients compared with controls. And DUSP1 was negatively correlated with resting mast cells (r = −0.703, P < 0.01), whereas it was positively correlated with neutrophils (r = 0.339, P < 0.05). Both in vivo and in vitro models confirmed the upregulated expression of DUSP1 and the downregulated expression of miR-429.

Conclusion

This study identified the ceRNA-based AC079305/DUSP1 axis as a promising OS-related signature for IS. Immune infiltrating cells, especially mast cells, may exert a pivotal role in IS progression. Pharmacological agents targeting signatures, their receptors, or mast cells may shed a novel light on therapeutic targets for IS.

The Possible Uses and Challenges of Nanomaterials in Mast Cell Research

Mast cells are tissue-resident immune cells that are involved in inflammation and fibrosis but also serve beneficial roles, including tissue maintenance, angiogenesis, pathogen clearance, and immunoregulation. Their multifaceted response and the ability of their mediators to target multiple organs and tissues means that mast cells play important roles in numerous conditions, including asthma, atopic dermatitis, drug sensitivities, ischemic heart disease, Alzheimer disease, arthritis, irritable bowel syndrome, infections (parasites, bacteria and viruses), and cancer. As a result, mast cells have become an important target for drug discovery and diagnostic research. Recent work has focused on applying novel nanotechnologies to explore cell biology. In this brief review, we will highlight the use of nanomaterials to modify mast cell functions and will discuss the potential of these technologies as research tools for understanding mast cell biology.

Nanoquantitative Structure-Property Relationship Modeling on C42Fullerene Isomers

The interest of scientists in nanostructures has been increased in the last years and proper methods for their assessment are needed.In silicomethods found their usefulness in the replacement of experimental evaluation and are successfully used as efficient alternatives for estimation and prediction of compound’s properties or activities. In this paper, it is shown that a Quantitative Structure-Property Relationship method is proper to be applied also on nanostructures. Based on computational experiment, several models to describe the total strain energy of C42fullerene isomers were obtained and their characteristics are presented. Furthermore, the best performing model obtained on C42fullerene isomers was validated on C40fullerene isomers.