BRD4 targeting nanotherapy prevents lipopolysaccharide induced acute respiratory distress syndrome

Polymer-lipid hybrid nanomedicines to deliver siRNA in and against glioblastoma cells

Small interfering RNA (siRNA) holds great potential to treat many difficult-to-treat diseases, but its delivery remains the central challenge. This study aimed at investigating the suitability of polymer-lipid hybrid nanomedicines (HNMeds) as novel siRNA delivery platforms for locoregional therapy of glioblastoma. Two HNMed formulations were developed from poly(lactic-co-glycolic acid) polymer and a cationic lipid: 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) or 3ß-[N-(N',N'-dimethylaminoethane)-carbamoyl]cholesterol (DC-Chol). After characterization of the HNMeds, a model siRNA was complexed onto their surface to form HNMed/siRNA complexes. The physicochemical properties and siRNA binding ability of complexes were assessed over a range of nitrogen-to-phosphate (N/P) ratios to optimize the formulations. At the optimal N/P ratio of 10, complexes effectively bound siRNA and improved its protection from enzymatic degradation. Using the NIH3T3 mouse fibroblast cell line, DOTAP-based HNMeds were shown to possess higher cytocompatibility in vitro over the DC-Chol-based ones. As proof-of-concept, uptake and bioefficacy of formulations were also assessed in vitro on U87MG human glioblastoma cell line expressing luciferase gene. Complexes were able to deliver anti-luciferase siRNA and induce a remarkable suppression of gene expression. Noteworthy, the effect of DOTAP-based formulation was not only about three-times higher than DC-Chol-based one, but also comparable to lipofectamine model transfection reagent. These findings set the basis to exploit this nanosystem for silencing relevant GB-related genes in further in vitro and in vivo studies.

Protective effect of olopatadine hydrochloride against LPS-induced acute lung injury: via targeting NF-κB signaling pathway

BACKGROUND

Morbidity and mortality rates associated with acute lung injury/acute respiratory distress syndrome (ALI/ARDS) are high (30-40%). Nuclear factor-kappa B (NF-κB) is a transcription factor, associated with transcription of numerous cytokines leading to cytokine storm, and thereby, plays a major role in ALI/ARDS and in advanced COVID-19 syndrome.

METHODS

Considering the role of NF-κB in ALI, cost-effective in silico approaches were utilized in the study to identify potential NF-κB inhibitor based on the docking and pharmacokinetic results. The identified compound was then pharmacologically validated in lipopolysaccharide (LPS) rodent model of acute lung injury. LPS induces ALI by altering alveolar membrane permeability, recruiting activated neutrophils and macrophages to the lungs, and compromising the alveolar membrane integrity and ultimately impairs the gaseous exchange. Furthermore, LPS exposure is associated with exaggerated production of various proinflammatory cytokines in lungs.

RESULTS

Based on in silico studies Olopatadine Hydrochloride (Olo), an FDA-approved drug was found as a potential NF-κB inhibitor which has been reported for the first time, and considered further for the pharmacological validation. Intraperitoneal LPS administration resulted in ALI/ARDS by fulfilling 3 out of the 4 criteria described by ATS committee (2011) published workshop report. However, treatment with Olo attenuated LPS-induced elevation of proinflammatory markers (IL-6 and NF-κB), oxidative stress, neutrophil infiltration, edema, and damage in lungs. Histopathological studies also revealed that Olo treatment significantly ameliorated LPS-induced lung injury, thus conferring improvement in survival. Especially, the effects produced by Olo medium dose (1 mg/kg) were comparable to dexamethasone standard.

CONCLUSION

In nutshell, inhibition of NF-κB pathway by Olo resulted in protection and reduced mortality in LPS- induced ALI and thus has potential to be used clinically to arrest disease progression in ALI/ARDS, since the drug is already in the market. However, the findings warrant further extensive studies, and also future studies can be planned to elucidate its role in COVID-19-associated ARDS or cytokine storm.

BRD4 as a Therapeutic Target in Pulmonary Diseases

Bromodomain and extra-terminal domain (BET) proteins are epigenetic modulators that regulate gene transcription through interacting with acetylated lysine residues of histone proteins. BET proteins have multiple roles in regulating key cellular functions such as cell proliferation, differentiation, inflammation, oxidative and redox balance, and immune responses. As a result, BET proteins have been found to be actively involved in a broad range of human lung diseases including acute lung inflammation, asthma, pulmonary arterial hypertension, pulmonary fibrosis, and chronic obstructive pulmonary disease (COPD). Due to the identification of specific small molecular inhibitors of BET proteins, targeting BET in these lung diseases has become an area of increasing interest. Emerging evidence has demonstrated the beneficial effects of BET inhibitors in preclinical models of various human lung diseases. This is, in general, largely related to the ability of BET proteins to bind to promoters of genes that are critical for inflammation, differentiation, and beyond. By modulating these critical genes, BET proteins are integrated into the pathogenesis of disease progression. The intrinsic histone acetyltransferase activity of bromodomain-containing protein 4 (BRD4) is of particular interest, seems to act independently of its bromodomain binding activity, and has implication in some contexts. In this review, we provide a brief overview of the research on BET proteins with a focus on BRD4 in several major human lung diseases, the underlying molecular mechanisms, as well as findings of targeting BET proteins using pharmaceutical inhibitors in different lung diseases preclinically.

Bromodomain protein 4 mediates the roles of TGFβ1-induced Stat3 signaling in mouse liver fibrogenesis

Epigenetic reader Bromodomain protein 4 (BrD4) functions as a global genomic regulator to direct hepatic stellate cell (HSC) activation (a key step in liver fibrogenesis) and liver fibrosis. The pivotal pro-fibrotic cytokine transforming growth factor-β1 (TGFβ1) signals through both Smad and Stat3 to elicit a wide array of biological effects. Stat3 is widely acknowledged as a regulator of gene transcription and is involved in fibrosis of multiple tissues. The present study focused on BrD4 function implication in the roles of TGFβ1-induced Stat3 signaling in HSC activation and liver fibrosis by using heterozygous TGFβ1 knockout mice and HSC culture. Results showed that Stat3 was required for TGFβ1-induced BrD4 expression in HSCs. BrD4 expression paralleled Stat3 activation in activated HSCs in human cirrhotic livers. BrD4 was involved in the roles of TGFβ1-induced Stat3 in HSC activation and liver fibrogenesis. Smad3 bound to phosphorylated-Stat3 and contributed to TGFβ1-induced Stat3 signaling. BrD4 expression induced by Stat3 signaling required the early-immediate gene Egr1. Egr1 had a positive feedback on Stat3 activation. In conclusion, a network consisting of Stat3 signaling, Smad3 signaling, Egr1, and BrD4 was involved in the effects of TGFβ1 on liver fibrosis, providing new toxicological mechanisms for TGFβ1 in liver fibrogenesis.

Polysaccharide-Based Nanomedicines Targeting Lung Cancer

A primary illness that accounts for a significant portion of fatalities worldwide is cancer. Among the main malignancies, lung cancer is recognised as the most chronic kind of cancer around the globe. Radiation treatment, surgery, and chemotherapy are some medical procedures used in the traditional care of lung cancer. However, these methods lack selectivity and damage nearby healthy cells. Several polysaccharide-based nanomaterials have been created to transport chemotherapeutics to reduce harmful and adverse side effects and improve response during anti-tumour reactions. To address these drawbacks, a class of naturally occurring polymers called polysaccharides have special physical, chemical, and biological characteristics. They can interact with the immune system to induce a better immunological response. Furthermore, because of the flexibility of their structures, it is possible to create multifunctional nanocomposites with excellent stability and bioavailability for the delivery of medicines to tumour tissues. This study seeks to present new views on the use of polysaccharide-based chemotherapeutics and to highlight current developments in polysaccharide-based nanomedicines for lung cancer.

Negative air ions through the action of antioxidation, anti-inflammation, anti-apoptosis and angiogenesis ameliorate lipopolysaccharide induced acute lung injury and promote diabetic wound healing in rat

Negative air ions (NAIs) being bioactive and negative charged molecules may confer antioxidant and anti-inflammatory activity. We assessed the effect of NAIs on two inflammatory diseases in animal models including lipopolysaccharide (LPS) induced acute lung injury (ALI) and wound healing in diabetic rats. We used intra-tracheal infusion of LPS to induce ALI and made a full-thickness cutaneous wound in streptozotocin-induced diabetic female Wistar rats. We evaluated NAIs effects on reactive oxygen species amount, leukocyte infiltration, wound healing rate, western blot, and immunohistochemistry in the lungs of ALI and skin sections of wounds. Our data found NAIs exposed saline displayed higher antioxidant activity vs. non-exposed saline. NAIs exposure did not significantly affect arterial blood pressure and respiratory frequency in control and LPS treated groups. LPS increased leukocyte infiltration, caspase 3/Poly-ADP-ribose-polymerase-mediated apoptosis formation and decreased Beclin-1/LC3-II-mediated autophagy in lungs. NAIs exposure conferred pulmonary protection by depressed leukocyte infiltration and caspase 3/Poly-ADP-ribose-polymerase mediated apoptosis and enhanced LC3-II-mediated autophagy in LPS induced ALI. NAIs treatment resulted in a significantly accelerated wound closure rate, decreased erythrocyte accumulation and leukocyte infiltration mediated oxidative stress and inflammation, and upregulated expression of skin collagen, vascular endothelial growth factor receptor-2 (VEGFR-2) and factor transforming growth factor-beta 1 (TGF-β1) vs non-treated group. Based on these results, it is suggested that NAIs conferred a protection through the upregulating LC3-II-dependent autophagy mechanism and downregulating leukocyte infiltration mediated inflammation and caspase 3/Poly-ADP-ribose-polymerase signaling in the LPS-treated ALI and promoted diabetic wound healing through the enhancing skin collagen synthesis, VEGFR-2 and TGF-β1 pathways.

Glycyrrhetinic acid: A potential drug for the treatment of COVID-19 cytokine storm

BACKGROUND

The cytokine storm (CS) triggered by coronavirus disease 2019 (COVID-19) has caused serious harm to health of humanity and huge economic burden to the world, and there is a lack of effective methods to treat this complication.

PURPOSE

In this research, we used network pharmacology and molecular docking to reveal the interaction mechanism in the glycyrrhetinic acid (GA) for the treatment of CS, and validated the effect of GA intervention CS by experiments.

STUDY DESIGN

First, we screened corresponding target of GA and CS from online databases, and obtained the action target genes through the Venn diagram. Then, protein-protein interaction (PPI) network, Gene ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment of the action target genes were acquired by R language to predict its mechanism. Next, molecular docking was performed on core targets. Finally, experiments in which GA intervened in lipopolysaccharide (LPS)-induced CS were implemented.

RESULTS

84 action target genes were obtained from online database. The PPI network of target genes showed that TNF, IL6, MAPK3, PTGS2, ESR1 and PPARG were considered as the core genes. The results of GO and KEGG showed that action target genes were closely related to inflammatory and immune related signaling pathways, such as TNF signaling pathway, IL-17 signaling pathway, Human cytomegalovirus infection, PPAR signaling pathway and so on. Molecule docking results prompted that GA had fine affinity with IL6 and TNF proteins. Finally, in vivo and in vitro experimental results showed that GA could significantly inhibit LPS-induced CS.

CONCLUSION

GA has a potential inhibitory effect on CS, which is worthy of further exploration.

Network pharmacology and experimental validation identify the potential mechanism of sophocarpine for COVID-19

Introduction. Coronavirus disease 2019 (COVID-19) has caused a serious threat to public health worldwide, and there is currently no effective therapeutic strategy for treating COVID-19.Hypothesis/Gap Statement. We propose that sophocarpine (SOP) might have potential therapeutic effects on COVID-19 through inhibiting the cytokine storm and the nuclear factor NF-κB signalling pathway.Aim. The objective was to elucidate the potential mechanism of SOP against COVID-19 through a network pharmacology analysis and its experimental validation.Methodology. The BATMAN-TCM database was used to identify the therapeutic targets of SOP, while the GeneCards and DisGeNET databases were used to identify the targets related to COVID-19. A protein-protein interaction (PPI) network was constructed from the STRING and analysed using Cytoscape software. Gene ontology (GO), Kyoto Encyclopaedia of Genes and Genomes (KEGG) and disease ontology (DO) enrichment analyses of the co-targets were performed using Metascape. Autodock 4.2.6 and Pymol software were applied for molecular docking. Levels of the proinflammatory cytokines IL-6, TNFα and IL-1β were measured by ELISA, while mRNA expression levels of intercellular adhesion molecule 1 (ICAM-1), vascular endothelial growth factor A (VEGFA) and IFN gamma (IFNG) were detected by real-time quantitative reverse transcription PCR. The protein levels of the molecules involved in the NF-κB signalling pathway were validated by western blot analysis.Results. A total of 65 co-targets of SOP and COVID-19 were determined. GO and KEGG enrichment analyses suggested that SOP affected COVID-19 by regulating the IL-17 signalling pathway, TNF signalling pathway and other signalling pathways. The PPI network and molecular docking showed that p65, ICAM-1 and VEGFA were key targets of SOP against COVID-19 and the underlying mechanism was validated in A549 cells in vitro. SOP attenuated the LPS-induced production of TNF-α and IL-6 and downregulated the LPS-induced mRNA expression of ICAM-1, VEGFA and IFNG. Mechanistically, SOP pretreatment inhibited the phosphorylation of p65 and facilitated the activation of Nrf2.Conclusions. SOP has a potential therapeutic effect on COVID-19 through multiple pathways and targets, and inhibits the production of pro-inflammatory cytokines and molecules involved in the NF-κB signalling pathway.

N-Acetylcysteine in Mechanically Ventilated Rats with Lipopolysaccharide-Induced Acute Respiratory Distress Syndrome: The Effect of Intravenous Dose on Oxidative Damage and Inflammation

Treatment of acute respiratory distress syndrome (ARDS) is challenging due to its multifactorial aetiology. The benefit of antioxidant therapy was not consistently demonstrated by previous studies. We evaluated the effect of two different doses of intravenous (i.v.) N-acetylcysteine (NAC) on oxidative stress, inflammation and lung functions in the animal model of severe LPS-induced lung injury requiring mechanical ventilation. Adult Wistar rats with LPS (500 μg/kg; 2.2 mL/kg) were treated with i.v. NAC 10 mg/kg (NAC10) or 20 mg/kg (NAC20). Controls received saline. Lung functions, lung oedema, total white blood cell (WBC) count and neutrophils count in blood and bronchoalveolar lavage fluid, and tissue damage in homogenized lung were evaluated. NAC significantly improved ventilatory parameters and oxygenation, reduced lung oedema, WBC migration and alleviated oxidative stress and inflammation. NAC20 in comparison to NAC10 was more effective in reduction of oxidative damage of lipids and proteins, and inflammation almost to the baseline. In conclusion, LPS-instilled and mechanically ventilated rats may be a suitable model of ARDS to test the treatment effects at organ, systemic, cellular and molecular levels. The results together with literary data support the potential of NAC in ARDS.

Relevance of BET Family Proteins in SARS-CoV-2 Infection

The recent pandemic we are experiencing caused by the coronavirus disease 2019 (COVID-19) has put the world's population on the rack, with more than 191 million cases and more than 4.1 million deaths confirmed to date. This disease is caused by a new type of coronavirus, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). A massive proteomic analysis has revealed that one of the structural proteins of the virus, the E protein, interacts with BRD2 and BRD4 proteins of the Bromodomain and Extra Terminal domain (BET) family of proteins. BETs are essential to cell cycle progression, inflammation and immune response and have also been strongly associated with infection by different types of viruses. The fundamental role BET proteins play in transcription makes them appropriate targets for the propagation strategies of some viruses. Recognition of histone acetylation by BET bromodomains is essential for transcription control. The development of drugs mimicking acetyl groups, and thereby able to displace BET proteins from chromatin, has boosted interest on BETs as attractive targets for therapeutic intervention. The success of these drugs against a variety of diseases in cellular and animal models has been recently enlarged with promising results from SARS-CoV-2 infection studies.

Green Tea Polyphenol Catechins Inhibit Coronavirus Replication and Potentiate the Adaptive Immunity and Autophagy-Dependent Protective Mechanism to Improve Acute Lung Injury in Mice

Effective antiviral therapeutics are urgently required to fight severe acute respiratory syndrome (SARS) caused by a SARS coronavirus (SARS-CoV). Because polyphenol catechins could confer antioxidative, anti-inflammatory, antiviral, and antimicrobial activities, we assessed the therapeutic effects of catechins against SARS-CoV replication in Vero E6 cells, the preventive effect of catechins on CD25/CD69/CD94/CD8⁺ cytotoxic T lymphocytes-mediated adaptive immunity, and the protective effect on lipopolysaccharide-induced acute lung injury (ALI) in mice. We found that catechins containing 32.8% epigallocatechin gallate, 15.2% epicatechin gallate, 13.2 epicatechin, 10.8% epigallocatechin, 10.4% gallocatechin, and 4.4% catechin directly inhibited SARS-CoV replication at sub-micromolecular concentrations. Four-week catechins ingestion increased CD8⁺ T cell percentage, upregulated CD69⁺/CD25⁺/CD94-NKG2A/CD8⁺ T lymphocytes-mediated adaptive immunity, and increased type I cytokines release responding to ovalbumin/alum. Catechins significantly reduced lipopolysaccharide-induced cytokine storm and oxidative stress and ALI by inhibiting PI3K/AKT/mTOR signaling to upregulate Beclin-1/Atg5-Atg12/LC3-II-mediated autophagy mechanism. Pretreatment of autophagy inhibitor 3-Methyladenine reversed the inhibiting effects of catechins on the cytokines and oxidative stress levels and ALI. In conclusion, our data indicated that catechins directly inhibited SARS-CoV replication, potentiated the CD25/CD69/CD94/CD8⁺ T lymphocytes-mediated adaptive immunity and attenuated lipopolysaccharide-induced ALI and cytokine storm by PI3K/AKT/mTOR-signaling-mediated autophagy, which may be applied to prevent and/or treat SARS-CoV infection.