The NF-kappaB pathway

The Crohn Disease-associated ATG16L1T300A polymorphism regulates inflammatory responses by modulating TLR- and NLR-mediated signaling

The mechanisms by which the ATG16L1^T300A polymorphism affects cell function and causes an increased risk for the development of Crohn disease remain incompletely understood. Here we report that healthy individuals and mice bearing this polymorphism, even as heterozygotes, manifest enhanced TLR, and NLR cytokine and chemokine responses due to increased activation of NFKB. We elucidated the mechanism of the NFKB abnormality and found that in the ATG16L1^T300A cell, there is enhanced polyubiquitination of TRAF6 or RIPK2 resulting from the accumulation of SQSTM1/p62. Indeed, knockout of Sqstm1 in autophagy-deficient cells almost completely normalized TRAF6 or RIPK2 polyubiquitination and NFKB activation in these cells. Thus, by identifying that autophagy is a pathway-intrinsic homeostatic mechanism that restricts excessive TLR- or NLR-mediated inflammatory signaling, our findings shed new light on how the ATG16L1^T300A polymorphism sets the stage for the occurrence of Crohn disease.Abbreviations: 3-MA: 3-methyladenine; ATG16L1: autophagy related 16 like 1; ATG7: autophagy related 7; BMDM: bone marrow-derived macrophage; CD: Crohn disease; CXCL: C-X-C motif chemokine ligand; IBD: inflammatory bowel disease; iBMDM: immortalized mouse BMDM; IL1B/IL-1β: interleukin 1 beta; IL6: interleukin 6; KI: knockin; KO: knockout; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; LPS: lipopolysaccharide; MDP: muramyl dipeptide; MEF: mouse embryonic fibroblast; NFKB/NF-κB: nuclear factor kappa B; NFKBIA/IKBA: NFKB inhibitor alpha; NLR: NOD-like receptor; NOD: nucleotide-binding oligomerization domain containing; RIPK2: receptor interacting serine/threonine kinase 2; SNP: single nucleotide polymorphism; SQSTM1/p62: sequestosome 1; TLR: toll like receptor; TNF/TNF-α: tumor necrosis factor; TRAF6: TNF receptor associated factor 6; Ub: ubiquitin; WT: wild type.

Biological and Exploitable Crossroads for the Immune Response in Cancer and COVID-19

The outbreak of novel coronavirus disease 2019 (COVID-19) has exacted a disproportionate toll on cancer patients. The effects of anticancer treatments and cancer patients' characteristics shared significant responsibilities for this dismal outcome; however, the underlying immunopathological mechanisms are far from being completely understood. Indeed, despite their different etiologies, SARS-CoV-2 infection and cancer unexpectedly share relevant immunobiological connections. In the pathogenesis and natural history of both conditions, there emerges the centrality of the immune response, orchestrating the timed appearance, functional and dysfunctional roles of multiple effectors in acute and chronic phases. A significant number (more than 600) of observational and interventional studies have explored the interconnections between COVID-19 and cancer, focusing on aspects as diverse as psychological implications and prognostic factors, with more than 4000 manuscripts published so far. In this review, we reported and discussed the dynamic behavior of the main cytokines and immune system signaling pathways involved in acute vs. early, and chronic vs. advanced stages of SARS-CoV-2 infection and cancer. We highlighted the biological similarities and active connections within these dynamic disease scenarios, exploring and speculating on possible therapeutic crossroads from one setting to the other.

Corynoline Alleviates Osteoarthritis Development via the Nrf2/NF-κB Pathway

Purpose

OA is a multifactorial joint disease in which inflammation plays a substantial role in the destruction of joints. Corynoline (COR), a component of Corydalis bungeana Turcz., has anti-inflammatory effects.

Materials and Methods

We evaluated the significance and potential mechanisms of COR in OA development. The viabilities of chondrocytic cells upon COR exposure were assessed by CCK-8 assays. Western blot, qPCR, and ELISA were used to assess extracellular matrix (ECM) degeneration and inflammation. The NF-κB pathway was evaluated by western blot and immunofluorescence (IF). Prediction of the interacting proteins of COR was done by molecular docking, while Nrf2 knockdown by siRNAs was performed to ascertain its significance. Micro-CT, H&E, Safranin O-Fast Green (S-O), toluidine blue staining, and immunohistochemical examination were conducted to assess the therapeutic effects of COR on OA in destabilization of medial meniscus (DMM) models.

Results

COR inhibited ECM degeneration and proinflammatory factor levels and modulated the NF-κB pathway in IL-1β-treated chondrocytes. Mechanistically, COR bound Nrf2 to downregulate the NF-κB pathway. Moreover, COR ameliorated the OA process in DMM models.

Conclusion

We suggest that COR ameliorates OA progress through the Nrf2/NF-κB axis, indicating COR may have a therapeutic potential for OA.

A Dual Role for Cysteinyl Leukotriene Receptors in the Pathogenesis of Corneal Infection

Cysteinyl leukotrienes (CysLTs) have been defined as central mediators of inflammation. Despite our extensive understanding of these bioactive lipid mediators in the pathogenesis of diseases such as asthma, allergic rhinitis, and even neurological disorders, information regarding the eye is markedly lacking. As a result, this study examined the expression profiles of two major CysLT receptors, CysLT1 and CysLT2, in the cornea using experimental mouse models of Pseudomonas aeruginosa-induced keratitis with contrasting outcomes: susceptible C57BL/6 (B6) and resistant BALB/c. Postinfection, disparate levels of CysLT receptors were accompanied by distinct expression profiles for select proinflammatory and anti-inflammatory cell surface markers detected on macrophages and polymorphonuclear neutrophils between the two strains. Further, inhibition of either CysLT receptor converted the disease response of both strains, where corneal perforation was prevented in B6 mice, and BALB/c mice fared significantly worse. In addition, receptor antagonist studies revealed changes in inflammatory cell infiltrate phenotypes and an influence on downstream CysLT receptor signaling pathways. Although the B6 mouse model highlights the established proinflammatory activities related to CysLT receptor activation, results generated from BALB/c mice indicate a protective mechanism that may be essential to disease resolution. Further, basal expression levels of CysLT1 and CysLT2 were significantly higher in uninfected corneas of both mouse strains as opposed to during infection, suggestive of a novel role in homeostatic maintenance within the eye. In light of these findings, therapeutic targeting of CysLT receptors extends beyond inhibition of proinflammatory activities and may impact inflammation resolution, as well as corneal surface homeostasis.

Arachidonic acid supplementation attenuates adipocyte inflammation but not adiposity in high fat diet induced obese mice

Obesity is associated with low-grade chronic inflammation and has a remarkable role in the pathophysiology of metabolic complications. In triggering these inflammatory responses, the arachidonic acid (AA) cascade plays a key role. However, there is a lack of data on how supplementary AA would affect obesity, adipose tissue inflammation, and the AA cascade in obesity. This study aims to investigate how AA supplementation affects obesity, adipocyte morphology, inflammation, and AA cascade signaling. Male Swiss Albino mice were used in our experiment. The mice were fed high-fat diets to induce obesity, and these obese mice were treated with two different doses of AA for 3 weeks. A normal diet non-obese group and an untreated obese group were kept as controls. Bodyweight and daily food intake data were recorded during that period. After the treatment period, blood serum and white adipose tissue of the experimental mice were collected for colorimetric lipid profile tests, histology, and mRNA extraction. The ΔΔCT method was employed for calculating the relative mRNA expression of target genes. The findings of our study suggest that AA has no significant effects on body weight, visceral adiposity, adipose tissue morphology, and serum lipid profile. However, AA treatment has resulted in a significant down-regulation of pro-inflammatory markers as well as the COX pathway. Besides, up-regulation of 12/15-LOX has been observed, indicating the metabolism pathway of supplementary AA through the LOX pathway. Our findings indicate that AA treatment may not provide significant benefits in terms of body weight, visceral fat mass, or serum lipid profile. However, it has effectively alleviated obesity-induced adipocyte inflammation in high-fat diet-induced obese mice.

Study on the Active Constituents and Molecular Mechanism of Zhishi Xiebai Guizhi Decoction in the Treatment of CHD Based on UPLC-UESI-Q Exactive Focus, Gene Expression Profiling, Network Pharmacology, and Experimental Validation

As one of the most common clinical cardiovascular diseases (CVDs), coronary heart disease (CHD) is the most common cause of death in the world. It has been confirmed that Zhishi Xiebai Guizhi decoction (ZXGD), a classical prescription of the traditional Chinese medicine (TCM), has achieved certain effects in the treatment of CHD; however, the mechanism still remains controversial. In this paper, an integrated approach, including UPLC-UESI-Q Exactive Focus, gene expression profiling, network pharmacology, and experimental validation, was introduced to systematically investigate the mechanism of ZXGD in the treatment of CHD. First, UPLC-UESI-Q Exactive Focus was applied to identify the chemical compounds of ZXGD. Then, the targets of the components for ZXGD were predicted by MedChem Studio software embed in the integrative pharmacology-based research platform of TCM, and the differentially expressed genes (DEGs) of CHD were obtained by gene expression profiling in gene expression omnibus database. The common genes of the above two genes were obtained by Venn analysis as the targets of GXGD in treatment with CHD. Third, the core targets were screened out by protein-protein interaction network analysis, and the kyoto encyclopedia of genes and genomes pathway enrichment analysis was performed by the database for annotation, visualization, and integrated discovery bioinformatics resources. After that, the formula-herb-compound-target-pathway network was constructed to explore the mechanism of ZXGD in the treatment of CHD. Finally, molecular docking and the vitro experiment were carried out to validate some key targets. As a result, a total of 39 compounds, 12 core targets, and 4 pathways contributed to ZXGD for the treatment of CHD. This study preliminarily provided a foundation for the study on the mechanism against CHD for ZXGD and may be a reference for the compatibility mechanism and the extended application of TCM compound prescription.

Anti-Inflammatory and Immunoregulatory Action of Sesquiterpene Lactones

Sesquiterpene lactones (SL), characterized by their high prevalence in the Asteraceae family, are one of the major groups of secondary metabolites found in plants. Researchers from distinct research fields, including pharmacology, medicine, and agriculture, are interested in their biological potential. With new SL discovered in the last years, new biological activities have been tested, different action mechanisms (synergistic and/or antagonistic effects), as well as molecular structure–activity relationships described. The review identifies the main sesquiterpene lactones with interconnections between immune responses and anti-inflammatory actions, within different cellular models as well in in vivo studies. Bioaccessibility and bioavailability, as well as molecular structure–activity relationships are addressed. Additionally, plant metabolic engineering, and the impact of sesquiterpene lactone extraction methodologies are presented, with the perspective of biological activity enhancement. Sesquiterpene lactones derivatives are also addressed. This review summarizes the current knowledge regarding the therapeutic potential of sesquiterpene lactones within immune and inflammatory activities, highlighting trends and opportunities for their pharmaceutical/clinical use.

Insights into health promoting effects and myochemical profiles of pine mushroom Tricholoma matsutake

Tricholoma matsutake (TM) is a valuable edible mushroom that has attracted increasing attention due to its potential medicinal values and functional uses. However, the chemical composition and molecular mechanisms behinds TM are not specifically summarized yet. Hence, this review aims to systematically analyze the research progress on the characterization of chemical compositions and the reported health effects of TM in the last 20 years. The myochemical profiles of TM consist of proteins with amino acids, fatty acids, nucleic acids with their derivatives, polysaccharides, minerals, volatile components, phenolic compounds, and steroids. The bioactive substances in TM exert their health effects mainly by regulating body immunity and restoring the balance of the redox system. NF-κB signaling pathway and its downstream cytokines such as TNF-α and IL-6 are the key molecular mechanisms. In addition, MAPK, PI3K-Akt, and JAK-STAT are also involved. NF-κB, MAPK, and PI3K-Akt are also highly related to cancer regulation and thus TM has great anticancer potential. Considering that most studies have only investigated the dosage and inhibition rate of TM on cancer cell lines, more extensive studies need to focus on the specific molecular mechanisms behind these anticancer effects in the future.

Polyphenols inhibiting MAPK signalling pathway mediated oxidative stress and inflammation in depression

Depression is one of the most debilitating psychiatric disorders affecting people of all ages worldwide. Despite significant heterogeneity between studies, increased inflammation and oxidative stress have been found in depression. Oxidative stress and inflammation are involved in the pathogenesis of depression. In the current review, we discussed the markers of oxidative stress and inflammation in depressive disorder and the association between these markers and the antidepressant treatment. The role of natural polyphenols in regulating various cell signaling pathways related to oxidative stress and inflammation has also been reviewed. The inhibitory effect of polyphenols on several cell signaling pathways reveals the vital role of polyphenols in the prevention and treatment of depressive disorder. Understanding the mechanism of polyphenols implicated in the regulation of cell signaling pathways is essential for the identification of lead compounds and the development of novel effective compounds for the prevention and treatment of depressive disorder.

Enhanced pro-BDNF-p75NTR pathway activity in denervated skeletal muscle

AIMS

Brain derived neurotrophic factor (BDNF) and the related receptors TrkB and p75NTR are expressed in skeletal muscle, yet their functions remain to be fully understood. Skeletal muscle denervation, which occurs in spinal injury, peripheral neuropathies, and aging, negatively affects muscle mass and function. In this study, we wanted to understand the role of BDNF, TrkB, and p75NTR in denervation-induced adverse effects on skeletal muscle.

MAIN METHODS

Mice with unilateral sciatic denervation were used. Protein levels of pro- and mature BDNF, TrkB, p75NTR, activations of their downstream signaling pathways, and inflammation in the control and denervated muscle were measured with Western blot and tissue staining. Treatment with a p75NTR inhibitor and BDNF skeletal muscle specific knockout in mice were used to examine the role of p75NTR and pro-BDNF.

KEY FINDINGS

In denervated muscle, pro-BDNF and p75NTR were significantly upregulated, and JNK and NF-kB, two major downstream signaling pathways of p75NTR, were activated, along with muscle atrophy and inflammation. Inhibition of p75NTR using LM11A-31 significantly reduced JNK activation and inflammatory cytokines in the denervated muscle. Moreover, skeletal muscle specific knockout of BDNF reduced pro-BDNF level, JNK activation and inflammation in the denervated muscle.

SIGNIFICANCE

These results reveal for the first time that the upregulation of pro-BDNF and activation of p75NTR pathway are involved in denervation-induced inflammation in skeletal muscle. The results suggest that inhibition of pro-BDNF-p75NTR pathway can be a new target to treat skeletal muscle inflammation.

Reduction of Oxidative Stress in Peripheral Blood Mononuclear Cells Attenuates the Inflammatory Response of Fibroblast-like Synoviocytes in Rheumatoid Arthritis

The production and oxidation mechanism of reactive oxygen species (ROS) are out of balance in rheumatoid arthritis (RA). However, the correlation between ROS and T cell subsets in RA remains unclear. Peripheral blood mononuclear cells (PBMCs) from patients with RA (n = 40) and healthy controls (n = 10) were isolated from whole blood samples. Synovial tissues (n = 3) and synovial fluid (n = 10) were obtained from patients with RA. The repartition of T cell subsets and expression of ROS and cytokines were examined according to RA severity. Fibroblast-like synoviocytes (FLSs) from patients with RA were stimulated with PBMCs and the expression of inflammation-related molecules were measured by RT-PCR and cytokine array. Regulatory T cells from patients with moderate (5.1 > DAS28 ≥ 3.2) RA showed the highest expression of mitochondrial ROS among the groups based on disease severity. Although ROS levels steadily increased with RA severity, there was a slight decline in severe RA (DAS28 ≥ 5.1) compared with moderate RA. The expression of inflammatory cytokines in RA FLSs were significantly inhibited when FLSs were co-cultured with PBMCs treated with ROS inhibitor. These findings provide a novel approach to suppress inflammatory response of FLSs through ROS regulation in PBMCs.

Matrine ameliorates the inflammatory response and lipid metabolism in vascular smooth muscle cells through the NF-κB pathway

Atherosclerosis is a chronic inflammatory disease associated with inflammatory responses and the uncontrolled proliferation and excessive apoptosis of vascular smooth muscle cells. However, the effects of matrine on the inflammatory response, abnormal lipid metabolism and cell proliferation and apoptosis marker proteins in human aortic vascular smooth muscle cells (HAVSMCs) have not been elucidated. Therefore, the present study aimed to investigate the effect of matrine on an in vitro model of atherosclerosis using HAVSMCs. The HAVSMCs were divided into normal, model and matrine groups. The model group was treated with oxidized low-density lipoprotein (oxLDL), the matrine group was treated with oxLDL and matrine and the normal group was treated with physiological saline. Total cholesterol (TC), free cholesterol (FC) and cholesterol ester (CE) levels were measured in the cell supernatant. In addition, the relative mRNA levels of inflammatory factors were quantified using reverse transcription-quantitative PCR, and the cell proliferation and apoptosis rates were evaluated using Cell Counting Kit-8 and flow cytometry assays, respectively. The expression levels of proteins associated with proliferation and apoptosis were also determined using western blotting. The levels of TC, FC and CE and the mRNA levels of IL-1β, IL-6, and TNF-α in the matrine group were lower than those in the model group, but higher than those in the normal group. After 48 and 96 h of treatment, the cell proliferation and apoptotic rates were lower in the matrine group compared with the model group. The relative expression levels of Ki-67, proliferating cell nuclear antigen and Bax were decreased, while that of Bcl-2 was increased in the matrine group compared with the model group. In addition, the relative protein expression of nuclear factor κB (NF-κB) in the matrine group was lower than that in the model group, but higher than that in the normal group. In summary, matrine inhibited activation of the NF-κB pathway and reduced cell proliferation and apoptosis in the oxLDL-induced atherosclerosis model, and exhibited anti-inflammatory effects. These results suggest that matrine attenuated abnormal biological reactions in HAVSMCs through the NF-κB pathway.

Detoxification of Bee Venom Increases Its Anti-inflammatory Activity and Decreases Its Cytotoxicity and Allergenic Activity

Bee venom is a medicinal product that is widely used in traditional therapies owing to its excellent anti-inflammatory activity. However, the use of bee venom has shown adverse effects. Therefore, there is a need for research that can remove the cytotoxicity of bee venom and enhance its efficacy. In this study, we hydrolyzed melittin, the main component of bee venom, and removed the other components to eliminate the toxicity of bee venom. To compare the efficacy of bee venom and detoxified bee venom, we examined their antioxidant effects using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. In addition, cytotoxicity was confirmed in MCF 10A and RAW 264.7 cells, using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assay. Detoxified bee venom showed a strong antioxidant activity and decreased a cytotoxicity in MCF 10A and RAW 264.7 cells. The anti-inflammatory activity of detoxified bee venom and bee venom were assessed by comparison of the expression of inflammatory cytokine mRNA and phosphorylation of IκBα in RAW 264.7 cells. Degranulation in RBL-2H3 cells was analyzed through β-hexosaminidase release assay to confirm the allergenic activity of bee venom and detoxified bee venom. Treatment of the detoxified bee venom inhibited inflammatory cytokine mRNA expression, IκBα phosphorylation, and β-hexosaminidase release. Taken together, the results indicated that compared to bee venom, detoxified bee venom exhibited decreased cytotoxicity and allergenicity and increased anti-inflammatory activity. In conclusion, detoxification of bee venom efficiently decreases the adverse effects, making it suitable for medicinal applications.

Time-Dependent Protective and Pro-Resolving Effects of FPR2 Agonists on Lipopolysaccharide-Exposed Microglia Cells Involve Inhibition of NF-κB and MAPKs Pathways

Prolonged or excessive microglial activation may lead to disturbances in the resolution of inflammation (RoI). The importance of specialized pro-resolving lipid mediators (SPMs) in RoI has been highlighted. Among them, lipoxins (LXA4) and aspirin-triggered lipoxin A4 (AT-LXA4) mediate beneficial responses through the activation of N-formyl peptide receptor-2 (FPR2). We aimed to shed more light on the time-dependent protective and anti-inflammatory impact of the endogenous SPMs, LXA4, and AT-LXA4, and of a new synthetic FPR2 agonist MR-39, in lipopolysaccharide (LPS)-exposed rat microglial cells. Our results showed that LXA4, AT-LXA4, and MR-39 exhibit a protective and pro-resolving potential in LPS-stimulated microglia, even if marked differences were apparent regarding the time dependency and efficacy of inhibiting particular biomarkers. The LXA4 action was found mainly after 3 h of LPS stimulation, and the AT-LXA4 effect was varied in time, while MR-39′s effect was mainly observed after 24 h of stimulation by endotoxin. MR-39 was the only FPR2 ligand that attenuated LPS-evoked changes in the mitochondrial membrane potential and diminished the ROS and NO release. Moreover, the LPS-induced alterations in the microglial phenotype were modulated by LXA4, AT-LXA4, and MR-39. The anti-inflammatory effect of MR-39 on the IL-1β release was mediated through FPR2. All tested ligands inhibited TNF-α production, while AT-LXA4 and MR-39 also diminished IL-6 levels in LPS-stimulated microglia. The favorable action of LXA4 and MR-39 was mediated through the inhibition of ERK1/2 phosphorylation. AT-LXA4 and MR39 diminished the phosphorylation of the transcription factor NF-κB, while AT-LXA4 also affected p38 kinase phosphorylation. Our results suggest that new pro-resolving synthetic mediators can represent an attractive treatment option for the enhancement of RoI, and that FPR2 can provide a perspective as a target in immune-related brain disorders.

Inhibitory effect of Salvia coccinea on inflammatory responses through NF-κB signaling pathways in THP-1 cells and acute rat diabetes mellitus

Hyperglycemia-induced oxidative stress has been implicated in diabetes and its complications. Medicinal plants possessing antioxidant activity may decrease oxidative stress by scavenging radicals and reducing power activity and would be a promising strategy for the treatment of inflammatory disorders like diabetes. This study was designed to evaluate the antioxidant effect of Aqueous Extract of  S.coccinea leaf (AESL) in HG treated THP-1 cells and streptozotocin (STZ)-induced diabetic Wistar rats. AESL and the standard antidiabetic drug glibenclamide were administered orally by intragastric tube for 14 days and pre-treated HG grown THP-1 cells. AESL treatment reduced HG induced increase in ROS production, NF-κB dependent proinflammatory gene expression by influencing NF-κB nuclear translocation in THP-1 cells. Oral administration of AESL inhibited STZ-induced increase in serum lipid peroxidation, aspartate transaminase, alanine transaminase, and Lactate dehydrogenase of diabetic rats. Significant increase in activity of superoxide dismutase, catalase and glutathione peroxidase, and a reduced level of glutathione, were observed in AESL treatment. The results demonstrate that AESL is useful in controlling blood glucose and also has antioxidant potential to influence the translocation of NF-κB, protect damage caused by hyperglycemia-induced inflammation.

The Impact of the Renin-Angiotensin-Aldosterone System on Inflammation, Coagulation, and Atherothrombotic Complications, and to Aggravated COVID-19

Atherosclerosis is considered a disease caused by a chronic inflammation, associated with endothelial dysfunction, and several mediators of inflammation are up-regulated in subjects with atherosclerotic disease. Healthy, intact endothelium exhibits an antithrombotic, protective surface between the vascular lumen and vascular smooth muscle cells in the vessel wall. Oxidative stress is an imbalance between anti- and prooxidants, with a subsequent increase of reactive oxygen species, leading to tissue damage. The renin-angiotensin-aldosterone system is of vital importance in the pathobiology of vascular disease. Convincing data indicate that angiotensin II accelerates hypertension and augments the production of reactive oxygen species. This leads to the generation of a proinflammatory phenotype in human endothelial and vascular smooth muscle cells by the up-regulation of adhesion molecules, chemokines and cytokines. In addition, angiotensin II also seems to increase thrombin generation, possibly via a direct impact on tissue factor. However, the mechanism of cross-talk between inflammation and haemostasis can also contribute to prothrombotic states in inflammatory environments. Thus, blocking of the renin-angiotensin-aldosterone system might be an approach to reduce both inflammatory and thrombotic complications in high-risk patients. During COVID-19, the renin-angiotensin-aldosterone system may be activated. The levels of angiotensin II could contribute to the ongoing inflammation, which might result in a cytokine storm, a complication that significantly impairs prognosis. At the outbreak of COVID-19 concerns were raised about the use of angiotensin converting enzyme inhibitors and angiotensin receptor blocker drugs in patients with COVID-19 and hypertension or other cardiovascular comorbidities. However, the present evidence is in favor of continuing to use of these drugs. Based on experimental evidence, blocking the renin-angiotensin-aldosterone system might even exert a potentially protective influence in the setting of COVID-19.

Bioactivity, bioavailability, and gut microbiota transformations of dietary phenolic compounds: implications for COVID-19

The outbreak of mysterious pneumonia at the end of 2019 is associated with widespread research interest worldwide. The coronavirus disease-19 (COVID-19) targets multiple organs through inflammatory, immune, and redox mechanisms, and no effective drug for its prophylaxis or treatment has been identified until now. The use of dietary bioactive compounds, such as phenolic compounds (PC), has emerged as a putative nutritional or therapeutic adjunct approach for COVID-19. In the present study, scientific data on the mechanisms underlying the bioactivity of PC and their usefulness in COVID-19 mitigation are reviewed. In addition, antioxidant, antiviral, anti-inflammatory, and immunomodulatory effects of dietary PC are studied. Moreover, the implications of digestion on the putative benefits of dietary PC against COVID-19 are presented by addressing the bioavailability and biotransformation of PC by the gut microbiota. Lastly, safety issues and possible drug interactions of PC and their implications in COVID-19 therapeutics are discussed.

Narciclasine attenuates LPS-induced acute lung injury in neonatal rats through suppressing inflammation and oxidative stress

Acute lung injury (ALI) is a life-threatening disorder related to serious pulmonary inflammation. Narciclasine exhibits strong anti-inflammation activity and attenuates the reactive oxygen species (ROS) production. The present study aims to investigate the underlying mechanism related to the effect of narciclasine on the pathogenesis of neonatal acute lung injury (ALI). Narciclasine attenuated LPS-induced pathological injury and pulmonary edema. In addition, narciclasine suppressed the secretion of inflammatory cytokines, including necrosis factor-α (TNF-α), Interleukin (IL-6), IL-1β, monocyte chemotactic protein-1 (MCP-1) in serum, and inhibited the expressions of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in lung tissues of neonatal ALI rats. Furthermore, narciclasine alleviated oxidative stress and apoptosis in lung tissues. Importantly, narciclasine exerted an inhibition effect on NF-κB nuclear translocation and activation of Toll-like Receptor 4 (TLR4)/Nuclear factor (NF)-κB/Cyclooxygenase 2 (Cox2) signaling pathway. Taken together, narciclasine protected against lung injury via inhibition effect on excessive inflammation, oxidative stress and apoptosis, hence, narciclasine may be considered as an effective and novel agent for clinical therapeutic strategy of ALI Treatment.

PapRIV, a BV-2 microglial cell activating quorum sensing peptide

Quorum sensing peptides (QSPs) are bacterial peptides produced by Gram-positive bacteria to communicate with their peers in a cell-density dependent manner. These peptides do not only act as interbacterial communication signals, but can also have effects on the host. Compelling evidence demonstrates the presence of a gut-brain axis and more specifically, the role of the gut microbiota in microglial functioning. The aim of this study is to investigate microglial activating properties of a selected QSP (PapRIV) which is produced by Bacillus cereus species. PapRIV showed in vitro activating properties of BV-2 microglia cells and was able to cross the in vitro Caco-2 cell model and reach the brain. In vivo peptide presence was also demonstrated in mouse plasma. The peptide caused induction of IL-6, TNFα and ROS expression and increased the fraction of ameboid BV-2 microglia cells in an NF-κB dependent manner. Different metabolites were identified in serum, of which the main metabolite still remained active. PapRIV is thus able to cross the gastro-intestinal tract and the blood–brain barrier and shows in vitro activating properties in BV-2 microglia cells, hereby indicating a potential role of this quorum sensing peptide in gut-brain interaction.

Anti-Inflammatory Effect of Pineapple Rhizome Bromelain through Downregulation of the NF-κB- and MAPKs-Signaling Pathways in Lipopolysaccharide (LPS)-Stimulated RAW264.7 Cells

Bromelain is a mixture of proteolytic enzymes derived from pineapple (Ananas comosus) fruit and stem possessing several beneficial properties, particularly anti-inflammatory activity. However, the molecular mechanisms underlying the anti-inflammatory effects of bromelain are unclear. This study investigated the anti-inflammatory effects and inhibitory molecular mechanisms of crude and purified rhizome bromelains on lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophage cells. RAW264.7 cells were pre-treated with various concentrations of crude bromelain (CB) or purified bromelain (PB), and then treated with LPS. The production levels of pro-inflammatory cytokines and mediators, including nitric oxide (NO), interleukin (IL)-6, and tumor necrosis factor (TNF)-α were determined by Griess and ELISA assays. The expressions of inducible nitric oxide synthetase (iNOS), cyclooxygenase (COX)-2, nuclear factor kappa B (NF-κB), and mitogen-activated protein kinases (MAPKs)-signaling pathway-related proteins were examined by western blot analysis. The pre-treatment of bromelain dose-dependently reduced LPS-induced pro-inflammatory cytokines and mediators, which correlated with downregulation of iNOS and COX-2 expressions. The inhibitory potency of PB was stronger than that of CB. PB also suppressed phosphorylated NF-κB (p65), nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha, extracellular signal-regulated kinases, c-Jun amino-terminal kinases, and p38 proteins in LPS-treated cells. PB then exhibited potent anti-inflammatory effects on LPS-induced inflammatory responses in RAW264.7 cells by inhibiting the NF-κB and MAPKs-signaling pathways.

Inflammatory and Biomechanical Drivers of Endothelial-Interstitial Interactions in Calcific Aortic Valve Disease

Calcific aortic valve disease is dramatically increasing in global burden, yet no therapy exists outside of prosthetic replacement. The increasing proportion of younger and more active patients mandates alternative therapies. Studies suggest a window of opportunity for biologically based diagnostics and therapeutics to alleviate or delay calcific aortic valve disease progression. Advancement, however, has been hampered by limited understanding of the complex mechanisms driving calcific aortic valve disease initiation and progression towards clinically relevant interventions.

Nuclear factor-kappa B (NF-κB) in pathophysiology of Parkinson disease: Diverse patterns and mechanisms contributing to neurodegeneration

Parkinson's disease (PD), the most common movement disorder, comprises several pathophysiologic mechanisms including misfolded alpha-synuclein aggregation, inflammation, mitochondrial dysfunction, and synaptic loss. Nuclear Factor-Kappa B (NF-κB), as a key regulator of a myriad of cellular reactions, is shown to be involved in such mechanisms associated with PD, and the changes in NF-κB expression is implicated in PD. Alpha-synuclein accumulation, the characteristic feature of PD pathology, is known to trigger NF-κB activation in neurons, thereby propagating apoptosis through several mechanisms. Furthermore, misfolded alpha-synuclein released from degenerated neurons, activates several signaling pathways in glial cells which culminate in activation of NF-κB and production of pro-inflammatory cytokines, thereby aggravating neurodegenerative processes. On the other hand, NF-κB activation, acting as a double-edged sword, can be necessary for survival of neurons. For instance, NF-κB activation is necessary for competent mitochondrial function and deficiency in c-Rel, one of the NF-κB proteins, is known to propagate DA neuron loss via several mechanisms. Despite the dual role of NF-κB in PD, several agents by selectively modifying the mechanisms and pathways associated with NF-κB, can be effective in attenuating DA neuron loss and PD, as reviewed in this paper.

Systematic Understanding of Pathophysiological Mechanisms of Oxidative Stress-Related Conditions-Diabetes Mellitus, Cardiovascular Diseases, and Ischemia-Reperfusion Injury

Reactive oxygen species (ROS) plays a role in intracellular signal transduction under physiological conditions while also playing an essential role in diseases such as hypertension, ischemic heart disease, and diabetes, as well as in the process of aging. The influence of ROS has some influence on the frequent occurrence of cardiovascular diseases (CVD) in diabetic patients. In this review, we considered the pathophysiological relationship between diabetes and CVD from the perspective of ROS. In addition, considering organ damage due to ROS elevation during ischemia-reperfusion, we discussed heart and lung injuries. Furthermore, we have focused on the transient receptor potential (TRP) channels and L-type calcium channels as molecular targets for ROS in ROS-induced tissue damages and have discussed about the pathophysiological mechanism of the injury.

Isovitexin Depresses Osteoarthritis Progression via the Nrf2/NF-κB Pathway: An in vitro Study

Purpose

Osteoarthritis (OA) is a multifactorial joint disease and inflammatory processes contribute to joint destruction. Isovitexin (IVX) is a flavone component found in passion flower, Cannabis and, and the palm that is known for its anti-inflammatory properties.

Materials and Methods

This study investigated in vitro the role and underlying mechanism used by IVX in its regulation of OA development. Effects of IVX on the viability of chondrocytes were measured by CCK-8 assays. The phenotypes of extracellular matrix (ECM) degeneration and inflammation were measured by qPCR, Western blot, and ELISA; and NF-κB pathway was detected by immunofluorescence and Western blot. Molecular docking was applied to predict the interacting protein of IVX, while Nrf2 was knocked down by siRNAs to confirm its role.

Results

We demonstrated that IVX suppressed ECM degeneration and suppressed pro-inflammatory factors in IL-1β-treated chondrocytes. Additionally, IVX impact on NF-κB signaling in IL-1β-exposed chondrocytic cells; Mechanistically, it was also demonstrated in molecular docking and knock down studies that IVX might bind to Nrf2 to suppress NF-κB pathway.

Conclusion

Our data suggest that IVX halts OA disease advancement through the Nrf2/NF-κB axis, suggesting a possibility of IVX as a target for OA therapy.

Effect of cortisol on the immune-like response of rainbow trout (Oncorhynchus mykiss) myotubes challenged with Piscirickettsia salmonis

Salmonids are a species of high commercial value in Chilean aquaculture, where muscle is the final product of the industry. Fish can be affected by stress during intensive cultures, increasing susceptibility to infections. Recently, we reported that muscle is an important focus of immune reactions. However, studies have shown the immunosuppressive effect of stress only in lymphoid organs, and few studies have been conducted on muscle and immunity. Hence, we determine the effects of cortisol on the immune-like response of fish myotubes challenged with Piscirickettsia salmonis by three trials. First, rainbow trout primary culture of muscle was cultured and treated with cortisol (100 ng/mL) for 3 and 4 h. Second, myotubes were challenged with P. salmonis (MOI 50) for 4, 6 and 8 h. And third, muscle cell cultures were pretreated with cortisol and then challenged with P. salmonis. The mRNA levels of glucocorticoid pathway and innate immunity were evaluated by qPCR. Cortisol increased the klf15 levels and downregulated the innate immune-related tlr5m gene and antimicrobial peptides. P. salmonis challenge upregulated several immune-related genes. Finally, cortisol pretreatment followed by P. salmonis challenge differentially modulated stress- and immune-related genes. These data suggest that fish muscle cells possess an intrinsic immune response and are differentially regulated by cortisol, which could lead to bacterial outbreaks in muscle under stress conditions.

Dietary polyphenols suppress chronic inflammation by modulation of multiple inflammation-associated cell signaling pathways

The high failure rate of the reductionist approach to discover effective and safe drugs to treat chronic inflammatory diseases has led scientists to seek alternative ways. Recently, targeting cell signaling pathways has been utilized as an innovative approach to discover drug leads from natural products. Cell signaling mechanisms have been identified playing key role in diverse diseases by inducing proliferation, cell survival and apoptosis. Phytochemicals are known to be able to modulate the cellular and molecular networks which are associated to chronic diseases including cancer-associated inflammation. In this review, the roles of dietary polyphenols (apigenin, kaempferol, quercetin, curcumin, genistein, isoliquiritigenin, resveratrol and gallic acid) in modulating multiple inflammation-associated cell signaling networks are deliberated. Scientific databases on suppressive effects of the polyphenols on chronic inflammation via modulation of the pathways especially in the recent five years are gathered and critically analyzed. The polyphenols are able to modulate several inflammation-associated cell signaling pathways, namely nuclear factor-kappa β, mitogen activated protein kinases, Wnt/β-catenin and phosphatidylinositol 3-kinase and protein kinase B via selective actions on various components of the networks. The suppressive effects of the polyphenols on the multiple cell signaling pathways reveal their potential use in prevention and treatment of chronic inflammatory disorders. Understanding the mechanistic effects involved in modulation of the signaling pathways by the polyphenols is necessary for lead identification and development of future functional foods for prevention and treatment of chronic inflammatory diseases.

Inotodiol From Inonotus obliquus Chaga Mushroom Induces Atypical Maturation in Dendritic Cells

Dendritic cells (DCs) have the ability to stimulate naïve T cells that coordinate subsequent adaptive response toward an inflammatory response or tolerance depending on the DC differentiation level. Inotodiol, a lanostane triterpenoid found in Inonotus obliquus (wild Chaga mushroom), is a natural compound with a wide range of biological activities. In this study, we investigated whether inotodiol promotes the maturation of bone marrow-derived DCs (BMDCs) and inotodiol-treated BMDCs induce T cell activation. Inotodiol increased the expression of surface maturation markers, including MHC-I, MHC-II, CD86, and CD40, on BMDCs without affecting the production of various cytokines, including TNF-α and IL-12p40 in these cells. T cells primed with inotodiol-treated BMDCs proliferated and produced IL-2, without producing other cytokines, including IL-12p40 and IFN-γ. Injection of inotodiol into mice induced maturation of splenic DCs and IL-2 production, and the administration of inotodiol and inotodiol-treated BMDCs induced the proliferation of adoptively transferred CD8⁺ T cells in vivo. The phosphatidylinositol-3-kinase inhibitor wortmannin abrogated the upregulation of Akt phosphorylation and CD86 and MHC-II expression induced by inotodiol. However, inotodiol failed to induce phosphorylation of the IκB kinase and degradation of IκB-α, and increased expression of CD86 induced by inotodiol was not blocked by an IκB kinase inhibitor. These results suggest that inotodiol induces a characteristic type of maturation in DCs through phosphatidylinositol-3-kinase activation independent of NF-κB, and inotodiol-treated DCs enhance T cell proliferation and IL-2 secretion.

ZIP8 mediates the extracellular matrix degradation of nucleus pulposus cells via NF-κB signaling pathway

The extracellular matrix (ECM) degradation of nucleus pulposus cells (NPCs) is mainly induced by metalloproteinases (MMPs). Zn²⁺ is an essential component of MMPs, but the effect of Zn²⁺ importers in controlling ECM metabolism remains unclear. The purpose of this research was to identify the involvement of Zn²⁺ importers in ECM degradation induced by inflammatory stimuli and excessive mechanical stressing. In this study, NPCs from Sprague-Dawley (SD) rats were separated and cultured. FluoZin-3 AM staining was applied to detect [Zn²⁺]i in NPCs treated with Interleukin-1β (IL-1β) or cyclic tensile strain (CTS) with a Flexcell Strain Unit. We found that intracellular Zn²⁺ concentration ([Zn²⁺]i) elevated dramatically, and ZIP8 is the predominant Zn²⁺ importer among all importers in senescent NPCs. The [Zn²⁺]i and MMP expression level both increased in IL-1β and CTS treated NPCs. Furthermore, the expression of ZIP8 was also markedly increased. However, knockdown of ZIP8 with siRNA alleviated ECM degradation induced by inflammatory stimuli and CTS. Both stimuli activated NF-κB signaling pathway, and knockdown of ZIP8 effectively inhibited NF-κB signaling pathway activation. In conclusion, knockdown of ZIP8 can alleviate NPCs' ECM degradation caused by inflammatory stimuli and excessive mechanical stressing.

Senolytic agent Quercetin ameliorates intervertebral disc degeneration via the Nrf2/NF-κB axis

OBJECTIVE

Intervertebral disc degeneration (IDD) represents major cause of low back pain. Quercetin (QUE) is one of the approved senolytic agents. In this study, we evaluated the protective effects of QUE on IDD development and its underlying mechanism.

METHODS

Effects of senolytic agent QUE on the viability of nucleus pulposus cells (NPCs) were measured by CCK-8 assays and EdU staining. The senescence associated secreted phenotype (SASP) factors expressions were measured by qPCR, western blot, and ELISA; and NF-κB pathway was detected by immunofluorescence and western blot. Molecular docking was applied to predict the interacting protein of QUE; while Nrf2 was knocked down by siRNAs to confirm its role in QUE regulated senescence phenotype. X-ray, MRI, Hematoxylin-Eosin and Safranin O-Fast green staining were performed to evaluate the therapeutic effects of QUE on IDD in the puncture-induced rat model.

RESULTS

In in vitro experiments, QUE inhibited SASP factors expression and senescence phenotype in IL-1β-treated NPCs. Mechanistically, QUE suppressed IL-1β induced activation of the NF-κB pathway cascades; it was also demonstrated in molecular docking and knock down studies that QUE might bind to Keap1-Nrf2 complex to suppress NF-κB pathway. In vivo, QUE ameliorated the IDD process in the puncture-induced rat model.

CONCLUSIONS

Together the present work suggests that QUE inhibits SASP factors expression and senescence phenotype in NPCs and ameliorates the progression of IDD via the Nrf2/NF-κB axis, which supports senolytic agent QUE as a potential therapeutic agent for the treatment of IDD.

Extraction, Identification, and Health Benefits of Anthocyanins in Blackcurrants (Ribes nigrum L.)

The fruit of the blackcurrant (Ribes nigrum L.) is round-shaped, dark purple, bittersweet, and seed-containing edible berries. The blackcurrant has been used as a traditional medicine in both Asia and European countries. It is known as a rich source of antioxidants, largely due to its high content of phenolic compounds, especially anthocyanins. Studies on anthocyanins from blackcurrants have adopted different extraction methods and a panel of anthocyanins has been identified in them. Research on the health benefits of blackcurrant anthocyanins has also grown. To present a general overview of research in blackcurrant anthocyanins, this review focuses on the extraction methods of anthocyanins from blackcurrants and the molecular mechanisms underlying their health benefits.

BRMS1: a multifunctional signaling molecule in metastasis

Despite high mortality rates, molecular understanding of metastasis remains limited. It can be regulated by both pro- and anti-metastasis genes. The metastasis suppressor, breast cancer metastasis suppressor 1 (BRMS1), has been positively correlated with patient outcomes, but molecular functions are still being characterized. BRMS1 has been implicated in focal adhesion kinase (FAK), epidermal growth factor receptor (EGFR), and NF-κB signaling pathways. We review evidence that BRMS1 regulates these vast signaling pathways through chromatin remodeling as a member of mSin3 histone deacetylase complexes.

Inhibitory effects of Camellia japonica on cell inflammation and acute rat reflux esophagitis

Background

Excessive and continuous inflammation may be the main cause of various immune system diseases. Reflux esophagitis (RE) is a common gastroesophageal reflux disease (GERD). Camellia japonica has high medicinal value and has long been used as a traditional herbal hemostatic medicine in China and Korea. The purpose of this study is to explore the antioxidant and anti-inflammatory activities of CJE and its protective effect on RE.

Materials and methods

Buds from C. japonica plants were collected in the mountain area of Jeju, South Korea. Dried C. japonica buds were extracted with 75% ethanol. DPPH and ABTS radical scavenging assay were evaluated according to previous method. The ROS production and anti-inflammatory effects of C. japonica buds ethanol extract (CJE) were evaluated on LPS-induced RAW 264.7 cell inflammation. The protective effects of CJE on RE were conducted in a RE rat model.

Results

CJE eliminated over 50% of DPPH and ABTS radical at concentration of 100 and 200 µg/mL, respectively. CJE alleviated changes in cell morphology, reduced production of ROS, NO and IL-1β. Also, down-regulated expression levels of iNOS, TNF-α, phosphorylated NF-κB, IκBα, and JNK/p38/MAPK. CJE reduced esophageal tissue damage ratio (40.3%) and attenuation of histological changes. In addition, CJE down-regulated the expression levels of TNF-α, IL-1β, COX-2 and phosphorylation levels of NF-κB and IκBα in esophageal tissue.

Conclusions

CJE possesses good anti-oxidation and anti-inflammatory activity, and can improve RE in rats caused by gastric acid reflux. Therefore, CJE is a natural material with good anti-oxidant and anti-inflammatory activity and has the possibility of being a candidate phytomedicine source for the treatment of RE.

MiR-182 inhibits proliferation, migration, invasion and inflammation of endometrial stromal cells through deactivation of NF-κB signaling pathway in endometriosis

Endometriosis affects about 10-15% women for reproductive age, but it is not currently curable and the underlying etiology for this disease is still not clear. In the present study, functions and mechanisms of miR-182 and RELA in endometriosis were investigated. BAY 11-7082 was used to block NF-κB pathway. qRT-PCR, ELISA and western blot assays were employed to evaluate the expressions of miR-182 and RELA, inflammatory factors and epithelial-mesenchymal transition (EMT)-related markers, and activation of NF-κB pathway. MTT, wound healing or Transwell assays were used to evaluate the cell proliferation, migration and invasion capacities. Bioinformatic and dual-luciferase reporter assays were carried out to analyze the interaction between miR-182 and RELA. MiR-182 expression was decreased, while RELA was increased as developed from normal to eutopic and ectopic status, which was accompanied by upregulated inflammatory factors and EMT-related proteins. RELA was directly targeted by miR-182 in human endometrial stromal cells. Overexpression of RELA increased inflammation-associated and EMT-related markers expression, while miR-182 upregulation decreased the expression of these genes in a dose-dependent manner, which finally attenuated the proliferation, migration and invasion capacities of endometrial stromal cells through deactivation of NF-κB signaling pathway. Moreover, co-overexpression of RELA reversed the above effects induced by miR-182. In a word, miR-182 directly targeted RELA and inhibited proliferation, migration, invasion, EMT and inflammation of endometrial stromal cells through deactivation of NF-κB signaling pathway in endometriosis. These results provide new insights into the interaction between miR-182 and NF-κB pathway and their potential as therapeutic targets for treatment of endometriosis.

Network- and systems-based re-engineering of dendritic cells with non-coding RNAs for cancer immunotherapy

Dendritic cells (DCs) are professional antigen-presenting cells that induce and regulate adaptive immunity by presenting antigens to T cells. Due to their coordinative role in adaptive immune responses, DCs have been used as cell-based therapeutic vaccination against cancer. The capacity of DCs to induce a therapeutic immune response can be enhanced by re-wiring of cellular signalling pathways with microRNAs (miRNAs). Methods: Since the activation and maturation of DCs is controlled by an interconnected signalling network, we deploy an approach that combines RNA sequencing data and systems biology methods to delineate miRNA-based strategies that enhance DC-elicited immune responses. Results: Through RNA sequencing of IKKβ-matured DCs that are currently being tested in a clinical trial on therapeutic anti-cancer vaccination, we identified 44 differentially expressed miRNAs. According to a network analysis, most of these miRNAs regulate targets that are linked to immune pathways, such as cytokine and interleukin signalling. We employed a network topology-oriented scoring model to rank the miRNAs, analysed their impact on immunogenic potency of DCs, and identified dozens of promising miRNA candidates, with miR-15a and miR-16 as the top ones. The results of our analysis are presented in a database that constitutes a tool to identify DC-relevant miRNA-gene interactions with therapeutic potential (https://www.synmirapy.net/dc-optimization). Conclusions: Our approach enables the systematic analysis and identification of functional miRNA-gene interactions that can be experimentally tested for improving DC immunogenic potency.

Dectin-1-mediated suppression of RANKL-induced osteoclastogenesis by glucan from baker's yeast

Immunoreceptors expressed on osteoclast precursor cells modify osteoclast differentiation and bone resorption activity. Dectin-1 is a lectin receptor of β-glucan and is specifically expressed in osteoclast precursor cells. In this study, we evaluated the bioactivity of β-glucan on receptor activator of nuclear factor-kappa B ligand (RANKL)-induced osteoclastogenesis and observed that glucan from baker's yeast inhibited this process in mouse bone marrow cells and dectin-1-overexpressing RAW264.7 (d-RAW) cells. In conjunction, RANKL-induced nuclear factor of activated T cell c1 expression was suppressed, subsequently downregulating TRAP and Oc-stamp. Additionally, nuclear factor-kappa B activation and the expression of c-fos and Blimp1 were reduced in d-RAW cells. Furthermore, glucan from baker's yeast induced the degradation of Syk protein, essential factor for osteoclastogenesis. These results suggest that glucan from baker's yeast suppresses RANKL-induced osteoclastogenesis and can be applied as a new treatment strategy for bone-related diseases.

Stachydrine ameliorates the progression of intervertebral disc degeneration via the PI3K/Akt/NF-κB signaling pathway: in vitro and in vivo studies

Intervertebral disc degeneration (IDD) has been reported to be a major cause of low back pain. Stachydrine (STA) is present in the fruit juice of the Citrus genus and Leonurus heterophyllus, in non-negligible concentrations. In our study, we examined the protective effects of STA against IDD development as well as its underlying mechanism of action using both in vitro and in vivo experiments. STA exerted protective effects on the anabolism and catabolism of the extracellular matrix (ECM) in IL-1β-treated NPCs and inhibited the expression of pro-inflammatory factors in vitro. Mechanistically, STA suppressed the IL-1β-induced activation of PI3K/Akt/NF-κB signalling pathway cascades. Moreover, it was also demonstrated in molecular docking studies that STA has strong binding abilities to PI3K. Furthermore, STA ameliorated the progression of the IDD process in vivo in the puncture-induced rat model. In summary, our findings demonstrated that STA ameliorates the progression of IDD via the PI3K/Akt/NF-κB signalling pathway, which makes STA a promising therapeutic agent for the treatment of IDD.

Crosstalk between microglia and patient-derived glioblastoma cells inhibit invasion in a three-dimensional gelatin hydrogel model

BACKGROUND

Glioblastoma is the most common and deadly form of primary brain cancer, accounting for more than 13,000 new diagnoses annually in the USA alone. Microglia are the innate immune cells within the central nervous system, acting as a front-line defense against injuries and inflammation via a process that involves transformation from a quiescent to an activated phenotype. Crosstalk between GBM cells and microglia represents an important axis to consider in the development of tissue engineering platforms to examine pathophysiological processes underlying GBM progression and therapy.

METHODS

This work used a brain-mimetic hydrogel system to study patient-derived glioblastoma specimens and their interactions with microglia. Here, glioblastoma cells were either cultured alone in 3D hydrogels or in co-culture with microglia in a manner that allowed secretome-based signaling but prevented direct GBM-microglia contact. Patterns of GBM cell invasion were quantified using a three-dimensional spheroid assay. Secretome and transcriptome (via RNAseq) were used to profile the consequences of GBM-microglia interactions.

RESULTS

Microglia displayed an activated phenotype as a result of GBM crosstalk. Three-dimensional migration patterns of patient-derived glioblastoma cells showed invasion was significantly decreased in response to microglia paracrine signaling. Potential molecular mechanisms underlying with this phenotype were identified from bioinformatic analysis of secretome and RNAseq data.

CONCLUSION

The data demonstrate a tissue engineered hydrogel platform can be used to investigate crosstalk between immune cells of the tumor microenvironment related to GBM progression. Such multi-dimensional models may provide valuable insight to inform therapeutic innovations to improve GBM treatment.

Inhibition of PI3K/Akt/NF-κB signaling by Aloin for ameliorating the progression of osteoarthritis: In vitro and in vivo studies

Osteoarthritis (OA) is a progressive and degenerative joint disease. Aloin is a bitter and yellow-brown-coloured compound from the Aloe plant and is allowed for use in foods as a "natural flavour". In our study, we examined the protective effects of Aloin on the inhibition of OA development as well as its underlying mechanism in both in vitro and vivo experiments. In in-vitro experiments, the protective effect of aloin on the anabolism and catabolism of the extracellular matrix (ECM) induced by IL-1 β in chondrocytes by inhibiting the expression of pro-inflammatory factors, including TNF-α (p = 0.016), IL-6 (p = 0.006), iNOS (p = 0.001) and COX-2 (p = 0.006). Mechanistically, Aloin suppressed the IL-1β-induced activation of the PI3K/Akt/NF-κB signalling pathway cascades. Moreover, molecular docking studies demonstrated that Aloin bound strongly to PI3K. In vivo, Aloin ameliorated the OA process in the destabilization of the medial meniscus (DMM) model. In summary, our findings demonstrate that Aloin ameliorates the progression of OA via the PI3K/Akt/NF-κB signalling pathways, which supports Aloin as a promising therapeutic agent for the treatment of OA.

Toll like Receptor signalling by Prevotella histicola activates alternative NF-κB signalling in Cystic Fibrosis bronchial epithelial cells compared to P. aeruginosa

Cystic Fibrosis (CF), caused by mutations affecting the CFTR gene, is characterised by viscid secretions in multiple organ systems. CF airways contain thick mucus, creating a gradient of hypoxia, which promotes the establishment of polymicrobial infection. Such inflammation predisposes to further infection, a self-perpetuating cycle in mediated by NF-κB. Anaerobic Gram-negative Prevotella spp. are found in sputum from healthy volunteers and CF patients and in CF lungs correlate with reduced levels of inflammation. Prevotella histicola (P. histicola) can suppress murine lung inflammation, however, no studies have examined the role of P. histicola in modulating infection and inflammation in the CF airways. We investigated innate immune signalling and NF-kB activation in CF epithelial cells CFBE41o- in response to clinical stains of P. histicola and Pseudomonas aeruginosa (P. aeruginosa). Toll-Like Receptor (TLR) expressing HEK-293 cells and siRNA assays for TLRs and IKKα were used to confirm signalling pathways. We show that P. histicola infection activated the alternative NF-kB signalling pathway in CF bronchial epithelial cells inducing HIF-1α protein. TLR5 signalling was responsible for the induction of the alternative NF-kB pathway through phosphorylation of IKKα. The induction of transcription factor HIF-1α was inversely associated with the induction of the alternative NF-kB pathway and knockdown of IKKα partially restored canonical NF-kB activation in response to P. histicola. This study demonstrates that different bacterial species in the respiratory microbiome can contribute differently to inflammation, either by activating inflammatory cascades (P. aeruginosa) or by muting the inflammatory response by modulating similar or related pathways (P. histicola). Further work is required to assess the complex interactions of the lung microbiome in response to mixed bacterial infections and their effects in people with CF.

Respiratory exposure to PM2.5 soluble extract disrupts mucosal barrier function and promotes the development of experimental asthma

BACKGROUND

Air pollutants are important factors that contribute to the development and exacerbation of asthma, but experimental evidence still needs to be collected and the mechanisms still need to be addressed. In this study, we aimed to assess the association between PM2.5 exposure and asthma development. The effects of PM2.5 exposure on the barrier functions of airway epithelial cells were also determined.

METHODS

PM2.5 was collected from Nanjing, China, and its soluble extract was prepared. Human lung epithelial cells (BEAS-2B) were treated with different concentrations of soluble PM2.5 extract, and cell viability was detected by FACS using Annexin V-FITC staining. PM2.5-induced oxidative stress and inflammatory events were assessed by DCF-DA staining and qPCR. PM2.5-induced dysfunction of the airway epithelial barrier was assessed by measuring the expression of tight junction molecules. In vivo, BALB/c mice were treated with OVA in the presence or absence of PM2.5 solution, followed by exposure to OVA aerosols. Allergy-induced airway inflammation and lung injury were assessed by histopathological analyses.

RESULTS

Soluble PM2.5 extract exposure in vitro decreased the viability and increased apoptosis of airway epithelial cells. Soluble PM2.5 extract induced oxidative stress and enhanced pro-inflammatory factor expression by activating the NF-κB and MAPK signalling pathways, which were accompanied by reduced airway barrier function. The in vivo data demonstrated that PM2.5 exposure increased the effects of allergy sensitization after respiratory exposure to allergens, which led to the development of asthma.

CONCLUSION

This study suggests that exposure to soluble PM2.5 extract contributes to airway barrier dysfunction. The soluble mediators generated by airway epithelial cells in response to PM2.5 exposure orchestrate the breaking of inhalational tolerance and sensitization to allergic antigens, leading to the exacerbated development of asthma.

RNA-Seq-Based Whole Transcriptome Analysis of IPEC-J2 Cells During Swine Acute Diarrhea Syndrome Coronavirus Infection

The new emergence of swine acute diarrhea syndrome coronavirus (SADS-CoV) has resulted in high mortality in suckling pigs in China. To date, the transcriptional expression of host cells during SADS-CoV infection has not been documented. In this study, by means of RNA-Seq technology, we investigated the whole genomic expression profiles of intestinal porcine epithelial cells (IPEC-J2) infected with a SADS-CoV strain SADS-CoV-CH-FJWT-2018. A total of 24,676 genes were identified: 23,677 were known genes, and 999 were novel genes. A total of 1,897 differentially expressed genes (DEGs) were identified between SADS-CoV-infected and uninfected cells at 6, 24, and 48 h post infection (hpi). Of these, 1,260 genes were upregulated and 637 downregulated. A Gene Ontology enrichment analysis revealed that DEGs in samples from 6, 24, and 48 hpi were enriched in 79, 383, and 233 GO terms, respectively, which were mainly involved in immune system process, response to stimulus, signal transduction, and cytokine-cytokine receptor interactions. The 1,897 DEGs were mapped to 109 KEGG Ontology (KO) pathways classified into four main categories. Most of the DEGs annotated in the KEGG pathways were related to the immune system, infectious viral disease, and signal transduction. The mRNA of porcine serum amyloid A-3 protein (SAA3), an acute phase response protein, was significantly upregulated during the infection. Over-expressed SAA3 in IPEC-J2 cells drastically inhibited the replication of SADS-CoV, while under-expressed SAA3 promoted virus replication. To our knowledge, this is the first report on the profiles of gene expression of IPEC-J2 cells infected by SADS-CoV by means of RNA-Seq technology. Our results indicate that SADS-CoV infection significantly modified the host cell gene expression patterns, and the host cells responded in highly specific manners, including immune response, signal and cytokine transduction, and antiviral response. The findings provide important insights into the transcriptome of IPEC-J2 in SADS-CoV infection.

Nuclear Factor Kappa B Signaling Complexes in Acute Inflammation

Significance: Nuclear factor kappa B (NF-κB) is a master regulator of the inflammatory response and represents a key regulatory node in the complex inflammatory signaling network. In addition, selective NF-κB transcriptional activity on specific target genes occurs through the control of redox-sensitive NF-κB interactions. Recent Advances: The selective NF-κB response is mediated by redox-modulated NF-κB complexes with ribosomal protein S3 (RPS3), Pirin (PIR). cAMP response element-binding (CREB)-binding protein (CBP)/p300, peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α), activator protein-1 (AP-1), signal transducer and activator of transcription 3 (STAT3), early growth response protein 1 (EGR-1), and SP-1. NF-κB is cooperatively coactivated with AP-1, STAT3, EGR-1, and SP-1 during the inflammatory process, whereas NF-κB complexes with CBP/p300 and PGC-1α regulate the expression of antioxidant genes. PGC-1α may act as selective repressor of phospho-p65 toward interleukin-6 (IL-6) in acute inflammation. p65 and nuclear factor erythroid 2-related factor 2 (NRF2) compete for binding to coactivator CBP/p300 playing opposite roles in the regulation of inflammatory genes. S-nitrosylation or tyrosine nitration favors the recruitment of specific NF-κB subunits to κB sites. Critical Issues: NF-κB is a redox-sensitive transcription factor that forms specific signaling complexes to regulate selectively the expression of target genes in acute inflammation. Protein-protein interactions with coregulatory proteins, other transcription factors, and chromatin-remodeling proteins provide transcriptional specificity to NF-κB. Furthermore, different NF-κB subunits may form distinct redox-sensitive homo- and heterodimers with distinct affinities for κB sites. Future Directions: Further research is required to elucidate the whole NF-κB interactome to fully characterize the complex NF-κB signaling network in redox signaling, inflammation, and cancer.

The Integrative Role of Sulforaphane in Preventing Inflammation, Oxidative Stress and Fatigue: A Review of a Potential Protective Phytochemical

Cruciferous vegetables hold a myriad of bioactive molecules that are renowned for possessing unique medicinal benefits. Sulforaphane (SFN) is one of the potential nutraceuticals contained within cruciferous vegetables that is useful for improving health and diseased conditions. The objective of this review is to discuss the mechanistic role for SFN in preventing oxidative stress, fatigue, and inflammation. Direct and indirect research evidence is reported to identify the nontoxic dose of SFN for human trials, and effectiveness of SFN to attenuate inflammation and/or oxidative stress. SFN treatment modulates redox balance via activating redox regulator nuclear factor E2 factor-related factor (Nrf2). SFN may play a crucial role in altering the Keap1/Nrf2/ARE pathway (an intricate response to many stimuli or stress), which induces Nrf2 target gene activation to reduce oxidative stress. In addition, SFN reduces inflammation by suppressing centrally involved inflammatory regulator nuclear factor-kappa B (NF-κB), which in turn downregulates the expression of proinflammatory cytokines and mediators. Exercise may induce a significant range of fatigue, inflammation, oxidative stress, and/or organ damage due to producing excessive reactive oxygen species (ROS) and inflammatory cytokines. SFN may play an effective role in preventing such damage via inducing phase 2 enzymes, activating the Nrf2/ARE signaling pathway or suppressing nuclear translocation of NF-κB. In this review, we summarize the integrative role of SFN in preventing fatigue, inflammation, and oxidative stress, and briefly introduce the history of cruciferous vegetables and the bioavailability and pharmacokinetics of SFN reported in previous research. To date, very limited research has been conducted on SFN’s effectiveness in improving exercise endurance or performance. Therefore, more research needs to be carried out to determine the effectiveness of SFN in the field of exercise and lifestyle factors.

A unifying model of glucotoxicity in human renal proximal tubular epithelial cells and the effect of the SGLT2 inhibitor dapagliflozin

BACKGROUND

Glucotoxicity in renal tubular epithelial cells (RPTECs) contributes to the pathogenesis of diabetic nephropathy. Sodium-glucose cotransporter 2 (SGLT2) inhibitors may exert their renoprotective effect by preventing glucotoxicity. We tested whether the confirmed in capillary endothelial cells unifying model of glucotoxicity can be applied in RPTECs and the impact of dapagliflozin.

METHODS

In primary human RPTECs cultured in normal or high glucose medium in the presence or not of dapagliflozin, we assessed glucose consumption, SCLT2 expression, reactive oxygen species (ROS) production, glyceraldehyde 3-phosphate dehydrogenase (GAPDH) activity, D-sorbitol and methylglyoxal cell content, O-linked β-N-acetyl glucosamine (O-Glc-NAc)-modified proteins, protein kinase C (PKC) activity, transforming growth factor-β1 (TGF-β1), interleukin-8 (IL-8), cell necrosis, and cell apoptosis using colorimetric and immunoenzymatic assays, and western blotting.

RESULTS

High glucose increases SGLT2 expression and glucose consumption. ROS are overproduced, and GAPDH is inhibited. The accumulation due to GAPDH inhibition glycolytic products are diverted into four noxious pathways. The polyol pathway assessed by D-sorbitol, the hexosamine pathway determined by O-GlcNAc-modified proteins, the lipid synthesis pathway assessed by PKC activity, and the advanced glycation end-products (AGEs) formation assessed by methylglyoxal. Eventually, these paths lead to overproduction of TGF-β1 and IL-8, as well as to cell necrosis and apoptosis. Dapagliflozin ameliorates all the above cascade of events.

CONCLUSIONS

Our results support a unifying model for glucotoxicity in RPTECs. Dapagliflozin by decreasing the elevated glucose influx into the RPTECs under high glucose conditions ameliorates glucotoxicity.

Human Type I Interferon Antiviral Effects in Respiratory and Reemerging Viral Infections

Type I interferons (IFN-I) are a group of related proteins that help regulate the activity of the immune system and play a key role in host defense against viral infections. Upon infection, the IFN-I are rapidly secreted and induce a wide range of effects that not only act upon innate immune cells but also modulate the adaptive immune system. While IFN-I and many IFN stimulated genes are well-known for their protective antiviral role, recent studies have associated them with potential pathogenic functions. In this review, we summarize the current knowledge regarding the complex effects of human IFN-I responses in respiratory as well as reemerging flavivirus infections of public health significance and the molecular mechanisms by which viral proteins antagonize the establishment of an antiviral host defense. Antiviral effects and immune modulation of IFN-stimulated genes is discussed in resisting and controlling pathogens. Understanding the mechanisms of these processes will be crucial in determining how viral replication can be effectively controlled and in developing safe and effective vaccines and novel therapeutic strategies.