Pro-inflammatory Mediators Research Articles

Chemical characterization and pharmacological properties of polysaccharides from Allium roseum leaves: In vitro and in vivo assays

Allium roseum is amongst the most important wild medicinal plants. It is known for its diverse biological properties, including antioxidant, antibacterial and antidiabetic activities. In this work, the polysaccharides (PARLs) were ultrasonically extracted from Allium roesum leaves then purified and analyzed by several techniques. Chemical composition and GC–MS analysis showed that the obtained polysaccharides were composed mainly of glucose (40.20 %), mannose (25.30 %), fructose (10.60 %) and galacturonic acid (15.11 %). Moreover, PARLs exhibited a potent antioxidant effect with higher capacities up to 69.61 % and 71.72 % for DPPH and ABTS free radicals, respectively. Furthermore, PARLs significantly modulated inflammatory response by reducing TNF-α, IL-6, and IL-8 pro-inflammatory mediators and promoting the anti-inflammatory IL-10 mediator in LPS stimulated THP-1 derived macrophages. The in-vivo tests proved that the extract was able to decrease carrageenan-induced rat paw swelling by around 68.15 % after 4 h of treatment. PARLs, significantly reduced the growth of U87 (glioblastoma) and IGROV-1 cancer cells with IC50 values of about 4.27 and 7.89 mg/mL respectively. This research clearly shows that Allium roseum polysaccharides can be used as natural antioxidants with anti-inflammatory and anticancer properties.

Phenotypes of regulatory T cells in different stages of COPD

BackgroundPrevious studies have shown that failure to control inflammatory processes mediated by regulatory T (Treg) cells contributes to chronic obstructive pulmonary disease (COPD) development and progression. The activity of Treg cells depends on their phenotypic characteristics: resting Treg (rTreg, CD3+CD4+CD25+FOXP3+CD25++CD45RA+) and activated Treg (aTreg, CD3+CD4+CD25+FOXP3+CD25+++CD45RA−) cells exhibit immunosuppressive activity, while cytokine-secreting T cells (FrIII, CD3+CD4+CD25+FOXP3+CD25++CD45RA−) exhibit proinflammatory activity. Previous findings have shown an increased density of cytokine-secreting T cells in COPD patients experiencing exacerbation. However, the methods for evaluating COPD under stable conditions are lacking. AimTo evaluate Treg cell phenotypes in patients with different stages of COPD under stable conditions. MethodsPeripheral blood mononuclear cells (PBMCs) were isolated from non-obstructed smokers and ex-smokers (NOS group, n = 19) and COPD patients at different stages (COPD I-II group, n = 25; COPD III-IV group, n = 25). The phenotypic characteristics of Treg cells and Th17 cells and their respective intracellular cytokines were analyzed by flow cytometry. ResultsBoth obstructed groups showed an increase in the proportion of rTregs, while the COPD III-IV group showed additional increases in total Treg and Th17 cells and in IL-10+ cells. There was an increase in proinflammatory mediators (CD3+CD4+IL-17+ cells; CD3+CD4+RORγt+ cells) in the COPD I-II group. In contrast, the NOS group demonstrated high proportions of proinflammatory Treg cells and proinflammatory CD8+ T cells (CD3+CD8+IL-17+). ConclusionDespite the increase in both total Treg cells and the rTreg phenotype from the early stages of COPD, there was a decrease in cells expressing IL-10, suggesting a failure in controlling the inflammatory process. These events precede the progression of the inflammatory process mediated by Th17 cells.

Lipid Fraction from Agaricus brasiliensis as a Potential Therapeutic Agent for Lethal Sepsis in Mice.

Sepsis is a potentially fatal clinical condition that results from an immune imbalance in the host during an infection. It presents systemic alterations due to excessive activation of pro-inflammatory mediators that contribute to inflammation, formation of reactive species, and tissue damage. Anti-inflammatory mediators are then extensively activated to regulate this process, leading to immune exhaustion and, consequently, immunosuppression of the host. Considering the biological activities of the nutraceutical Agaricus brasiliensis (A. brasiliensis), such as immunomodulatory, antioxidant, and antitumor activities, the present study investigated the therapeutic potential of the lipid fraction of A. brasiliensis (LF) in a model of lethal sepsis in mice (Mus musculus), induced by cecal ligation and perforation (CLP). The results showed that treatment of septic animals with LF or LF associated with ertapenem (LF-Erta) reduced systemic inflammation, promoting improvement in clinical parameters and increased survival. The data show a reduction in pro-inflammatory and oxidative stress markers, regulation of the anti-inflammatory response and oxidizing agents, and increased bacterial clearance in the peritoneal cavity and liver. Thus, it can be concluded that LF as a treatment, and in conjunction with antibiotic therapy, has shown promising effects as a hepatoprotective, antioxidant, antimicrobial, and immunomodulatory agent.

Exosomal Src from hypoxic vascular smooth muscle cells exacerbates ischemic brain injury by promoting M1 microglial polarization

Inflammatory response mediated by M1 microglia is a crucial factor leading to the exacerbation of brain injury after ischemic stroke (IS). Under the stimulation of IS, vascular smooth muscle cells (VSMCs) switch to the synthetic phenotype characterized by exosome secretion. Previous studies have shown that exosomes play an important role in the regulation of microglial polarization. We reported that exosomes derived from primary human brain VSMCs under hypoxia (HExos), but not those under normoxia (Exos), significantly promoted primary human microglia (HM1900) shift to M1 phenotype. Proteomic analysis showed that the Src protein enriched in HExos was a potential pro-inflammatory mediator. In vitro experiments showed that the expression of Src and M1 markers were upregulated in HM1900 co-incubated with HExos. However, the Src inhibitor dasatinib (DAS) significantly promoted the transformation of HM1900 phenotype from M1 to M2. In vivo experiments of pMCAO mice also revealed that DAS could effectively inhibit the activation of M1 microglia/macrophages, protect neurons from apoptosis, and improve neuronal function. These data suggested that hypoxic-VSMCs-derived exosomes were involved in post-IS inflammation by promoting M1 microglial polarization through Src transmission. Targeting inhibition of Src potentially acts as an effective strategy for treating brain injury after IS.

Moderate Aerobic Exercise Induces Homeostatic IgA Generation in Senile Mice.

A T-cell-independent (TI) pathway activated by microbiota results in the generation of low-affinity homeostatic IgA with a critical role in intestinal homeostasis. Moderate aerobic exercise (MAE) provides a beneficial impact on intestinal immunity, but the action of MAE on TI-IgA generation under senescence conditions is unknown. This study aimed to determine the effects of long-term MAE on TI-IgA production in young (3 month old) BALB/c mice exercised until adulthood (6 months) or aging (24 months). Lamina propria (LP) from the small intestine was obtained to determine B cell and plasma cell sub-populations by flow cytometry and molecular factors related to class switch recombination [Thymic Stromal Lymphopoietin (TSLP), A Proliferation-Inducing Ligand (APRIL), B Cell Activating Factor (BAFF), inducible nitric oxide synthase (iNOS), and retinal dehydrogenase (RDH)] and the synthesis of IgA [α-chain, interleukin (IL)-6, IL-21, and Growth Factor-β (TGF-β)]; and epithelial cells evaluated IgA transitosis [polymeric immunoglobulin receptor (pIgR), tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), IL-4] by the RT-qPCR technique. The results were compared with data obtained from sedentary age-matched mice. Statistical analysis was computed with ANOVA, and p < 0.05 was considered to be a statistically significant difference. Under senescence conditions, MAE promoted the B cell and IgA+ B cells and APRIL, which may improve the intestinal response and ameliorate the inflammatory environment associated presumably with the downmodulation of pro-inflammatory mediators involved in the upmodulation of pIgR expression. Data suggested that MAE improved IgA and downmodulate the cytokine pro-inflammatory expression favoring homeostatic conditions in aging.

Signaling by Neutrophil G Protein-Coupled Receptors that Regulate the Release of Superoxide Anions.

In human peripheral blood, the neutrophil granulocytes (neutrophils) are the most-abundant white blood cells. These professional phagocytes are rapidly recruited from the bloodstream to inflamed tissues by chemotactic factors that signal danger. Neutrophils, which express many receptors that are members of the large family of G protein-coupled receptors (GPCRs), are critical for the elimination of pathogens and inflammatory insults, as well as for the resolution of inflammation leading to tissue repair. Danger-signaling molecular patterns such as the N-formylated peptides that are formed during bacterial and mitochondrial protein synthesis and recognized by formyl peptide receptors (FPRs) and free fatty acids recognized by free fatty acid receptors (FFARs) regulate neutrophil functions. Short peptides and short chain fatty acids activate FPR1 and FFA2R, respectively, while longer peptides and fatty acids activate FPR2 and GPR84, respectively. The activation profiles of these receptors include the release of reactive oxygen species (ROS) generated by the NADPH oxidase. Activation of the oxidase and the production of ROS are processes that are regulated by proinflammatory mediators, including TNFα and GM-CSF. The receptors have signaling and functional similarities, although there are also important differences, not only between the two closely related neutrophil FPRs, but also between the FPRs and the FFARs. In neutrophils, these receptors never walk alone, and additional mechanistic insights into the regulation of the GPCRs and the novel regulatory mechanisms underlying the activation of NADPH oxidase advance our understanding of the role of receptor transactivation in the regulation of inflammatory reactions.

Evaluation of the effect of roasting and digestion on biological activity of compounds of coffee extracts - in vitro assessment of the bioavailability, cytoprotective properties and modulation of inflammatory response

Coffee is the most consumed beverage in the world. Consumption of phenolic compounds present in coffee protects the body against oxidative stress generation, inflammatory response, and cancer development. The aim of the study was evaluation of biological activity of coffee extracts (obtained from green, as well as light and dark roasted Robusta and Arabica beans) and isolated fractions on human colon adenocarcinoma Caco-2 cells, which are used as a cellular model of intestinal barrier in bioavailability studies. Additionally, impact of coffee phenolics on oxidative stress level and anti-inflammatory activity has been studied with RAW 264.7 macrophages used in immunomodulatory research. It was demonstrated that the coffee constituents protection against oxidative stress, lipotoxicity and secretion of proinflammatory mediators is correlated with the presence of mono- and dichlorogenic acids and roasting process. It was demonstrated that coffee phytochemicals can decrease cells proliferation and bind to topoisomerase IIα being a dietary tool in cancer prevention.

Hydrolysis and cross-flow ultrafiltration as an alternative process to isolate fucoidans from edible seaweed Nizamuddinia zarnardinii with enhanced immunostimulatory efficacy

In the present investigation, fucoidan isolated from Nizamuddinia zanardinii was hydrolysed using 0.01 N HCl at boiling temperature for 10, 20, 40 and 60 min. Native and hydrolysed fucoidans contained a close chemical compositions, most importantly constituted of sulfates and uronic acids as well as fucose, galactose and mannose. Hydrolysis and cross-flow ultrafiltration produced fucoidan hydrolysates having different weight average molecular weights. The FH20 fucoidan was the most potent polysaccharide hydrolysate to stimulate NO-release from RAW264.7 macrophage cells. After cross-flow ultrafiltration of FH20, 100 < kDa fucoidan, polysaccharide with high branching degree consisting mainly of (1 → 2)-Fucp, (1 → 2,3)-Fucp, (1 → 3)-Galp, (1 → 2,3)-Galp, (1 → 2)-Manp and (1 → 3)-Manp residues, exerted the highest stimulation effect on RAW264.7 macrophage cells, secreting considerable NO, TNF-α, IL-1β, IL-6 and IL-12 proinflammatory mediators. Also, 100 < kDa fucoidan activated NK-92 cells to release TNF-α, INF-γ, granzyme-B, perforin, NKG2D and FasL. Both RAW264.7 and NK-92 cells were activated through NF-κB and MAPKs signalling pathways and the degree of stimulation capacity in fucoidan from N. zanardinii was in close correlation with the molecular weight.

Stress and Sleep Duration in Immune and Neuroendocrine Patterning. An Analytical Triangulation in ELSA.

Proinflammatory and neuroendocrine mediators are implicated in disease aetiopathogenesis. Stress increases concentrations of immune-neuroendocrine biomarkers through a complex network of brain-body signalling pathways. Suboptimal sleep further modulates these processes by altering major effector systems that sensitise the brain to stress. Given the ubiquitous, impactful nature of material deprivation, we tested for a synergistic association of financial stress and suboptimal sleep with these molecular processes. With data drawn from the English Longitudinal Study of Ageing (ELSA), associations were tested on 4,940 participants (~66±9.4 years) across four-years (2008-2012). Through analytical triangulation, we tested whether financial stress (>60% insufficient resources) and suboptimal sleep (≤5/≥9 hours) were independently and interactively associated with immune-neuroendocrine profiles, derived from a latent profile analysis (LPA) of C-reactive protein, fibrinogen, white blood cell counts, hair cortisol, and insulin-like growth factor-1. A three-class LPA model offered the greatest parsimony. After adjustment for genetic predisposition, sociodemographics, lifestyle, and health, financial stress was associated with short-sleep cross-sectionally (RRR=1.45; 95%CI=1.18-1.79; p<0.001) and longitudinally (RRR=1.31; 95%CI=1.02-1.68; p=0.035), and it increased risk of belonging to the high-risk biomarker profile by 42% (95%CI=1.12-1.80; p=0.004). Suboptimal sleep was not related to future risk of high-risk profile membership, nor did it moderate financial stress-biomarker profile associations. Results advance psychoneuroimmunological knowledge by revealing how immune-neuroendocrine markers cluster in older cohorts and respond to financial stress over time. Financial stress associations with short-sleep are supported. The null role of suboptimal sleep, as exposure and mediator, in profile membership, provides valuable insight into the dynamic role of sleep in immune-neuroendocrine processes.

Ameliorative effect of nodakenin in combating TNBS-induced ulcerative colitis by suppressing NFƙB-mediated NLRP3 inflammasome pathway.

Ulcerative colitis (UC) is an enduring and complex inflammatory bowel disease that is clinically prevalent, progressive, and debilitating. As of now, the few effective medical treatments for UC have unacceptably high side effects. It is crucial to find safer and more effective UC treatments. Nodakenin possesses anti-inflammatory and antioxidant activity by suppressing several pro-inflammatory mediators. In the present study, we aimed to evaluate the colonoprotective effect of nodakenin in combating colitis through the NFƙB-mediated NLRP3 inflammasome pathway. In mice, UC was induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS). Nodakenin (10, 20, and 40mg/kg) was introduced intragastrically, and disease activity index (DAI) score was calculated. Malondialdehyde (MDA), myeloperoxidase (MPO), superoxide dismutase (SOD), nitric oxide (NO) levels, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) concentration were evaluated in colon homogenate. Colon samples were used for histopathological investigation and mRNA expression studies involving nuclear factor kappa B (NFƙB), cyclooxygenase-2 (COX-2), inducible nitric oxide (iNOS), nucleotide-binding receptor domain 3 (NLRP3), interleukin-1β (IL-1β), and interleukin-18 (IL-18). Nodakenin treatment was found effective in lowering the DAI score, histological score, MPO, MDA, and NO levels while elevating SOD levels as compared to the model control group, showcasing its anti-inflammatory and antioxidant properties. Nodakenin (40mg/kg) significantly downregulated the expression of TNF-α, IL-6, NFƙB (1.24-fold), iNOS (1.2-fold), COX-2 (1.98-fold), NLRP3 (1.78-fold), IL-1β (1.29-fold), and IL-18 (1.17-fold) conferring its great anti-inflammatory potential in combating colitis. Taking together, nodakenin presumably alleviated TNBS-induced colitis by NFƙB-mediated NLRP3 inflammasome pathway and reduced colon damage by downregulating various transcriptional genes and pro-inflammatory mediators.

Beyond the classic players: Mas-related G protein-coupled receptor member X2 role in pruritus and skin diseases.

Chronic spontaneous urticaria (CSU), atopic dermatitis (AD), psoriasis and rosacea are highly prevalent inflammatory skin conditions which impose a significant burden on patients' quality of life. Their pathophysiology is likely multifactorial, involving genetic, immune and environmental factors. Recent advancements in the field have demonstrated the key role of mast cells (MC) in the pathophysiology of these conditions. The Mas-related G protein-coupled receptor X2 (MRGPRX2) has emerged as a promising non-IgE-mediated MC activation receptor. MRGPRX2 is predominately expressed on MC and activated by endogenous and exogenous ligands, leading to MC degranulation and release of various pro-inflammatory mediators. Mounting evidence on the presence of endogenous MRGPRX2 agonists (substance P, cortistatin-14, LL37, PAMP-12 and VIP) and its high expression among patients with CSU, AD, rosacea, psoriasis and chronic pruritus emphasizes the pathogenic role of MRGPRX2 in these conditions. Despite the currently available treatments, there remains a pressing need for novel drug targets and treatment options for these chronic inflammatory skin conditions. Here, we reviewed the pathogenic role of MRGPRX2 and its potential as a novel therapeutic target and provided an update on future research directions.

Novel therapeutic receptor agonists and antagonists in allergic conjunctivitis.

Allergic conjunctivitis is characterized by the development of pathophysiological changes to the ocular surface, which occurs when pro-allergic and pro-inflammatory mediators interact with their cognate receptors expressed on immune and nonimmune cells. Traditional treatments with antihistamines and corticosteroids provide relief, but there is a need for more efficacious and tolerable long-term therapy with a better safety profile. This article aims to provide an overview of the mode of action and clinical application of agonist therapies targeting glucocorticoid, melanocortin, and toll-like receptors, as well as antagonist therapies targeting cytokine, chemokine, integrin, and histamine receptors. There has been considerable advancement in immunology and pharmacology, as well as a greater understanding of the cellular and molecular mechanisms of allergic conjunctivitis. Recent research advancing therapy for allergic conjunctivitis has focused on developing synthetic molecules and biologics that can interfere with the process of the allergic immune reaction. This review discusses novel therapeutic receptors being explored agonistically or antagonistically to develop alternative treatment options for allergic conjunctivitis. These novel approaches hold promise for improving the management of allergic eye diseases, offering patients hope for more effective and safer treatment options in the future.

Sex hormone deprivation abolishes sex-specific differences in murine colon inflammation and related lipid mediator production.

Unresolved inflammation, due to unfavorable imbalances between pro-inflammatory and pro-resolving mediators, leads to chronic inflammatory pathologies that are often sex-biased and regulated by sex hormones, including inflammatory bowel disease. Lipid mediators (LM) produced from polyunsaturated fatty acids by various lipoxygenases (LOX) and cyclooxygenases govern all stages of inflammation, i.e., the initiation and progression by pro-inflammatory eicosanoids and its resolution by specialized pro-resolving mediators (SPM). Here, we reveal sex-specific differences in murine experimental colitis with male preponderance, which was abolished by sex hormone deprivation using gonadectomy, and this correlated to the levels of inflammation-relevant mediators in the colon. Oral dextran sodium sulfate administration caused more severe colon inflammation in male CD-1 mice than in female counterparts during the acute phase. Colitis in males yielded higher colonic cytokine/chemokine levels but lower 12-/15-LOX-derived LM including SPM compared to female animals in the resolving phase. Sex hormone deprivation in male mice by orchidectomy ameliorated colitis and impaired pro-inflammatory cytokine/chemokine levels but elevated 12-/15-LOX products including SPM, thus abolishing the observed sex differences. Conversely, ovariectomy impaired the levels of those LM that dominated in females and that were increased in males after gonadectomy. Our findings suggest that male sex hormones promote the development of colitis connected to the biosynthesis of inflammatory cytokines, chemokines, and certain LM, especially pro-resolving 12-/15-LOX products that appear to be suppressed in the male colon due to androgens.

Bioactive Hydrogel Formulation Based on Ferulic Acid-Grafted Nano-Chitosan and Bacterial Nanocellulose Enriched with Selenium Nanoparticles from Kombucha Fermentation.

Selenium nanoparticles (SeNPs) have specific properties that result from their biosynthesis particularities. Chitosan can prevent pathogenic biofilm development. A wide palette of bacterial nanocellulose (BNC) biological and physical-chemical properties are known. The aim of this study was to develop a hydrogel formulation (SeBNCSFa) based on ferulic acid-grafted chitosan and bacterial nanocellulose (BNC) enriched with SeNPs from Kombucha fermentation (SeNPsK), which could be used as an adjuvant for oral implant integration and other applications. The grafted chitosan and SeBNCSFa were characterized by biochemical and physical-chemical methods. The cell viability and proliferation of HGF-1 gingival fibroblasts were investigated, as well as their in vitro antioxidant activity. The inflammatory response was determined by enzyme-linked immunosorbent assay (ELISA) of the proinflammatory mediators (IL-6, TNF-α, and IL-1β) in cell culture medium. Likewise, the amount of nitric oxide released was measured by the Griess reaction. The antimicrobial activity was also investigated. The grafting degree with ferulic acid was approximately 1.780 ± 0.07% of the total chitosan monomeric units, assuming single-site grafting per monomer. Fourier-transform infrared spectroscopy evidenced a convolution of BNC and grafted chitosan spectra, and X-ray diffraction analysis highlighted an amorphous rearrangement of the diffraction patterns, suggesting multiple interactions. The hydrogel showed a high degree of cytocompatibility, and enhanced antioxidant, anti-inflammatory, and antimicrobial potentials.

PRRSV infection facilitates the shedding of soluble CD163 to induce inflammatory responses

Porcine reproductive and respiratory syndrome (PRRS), which poses substantial threats to the global pig industry, is primarily characterized by interstitial pneumonia. Cluster of differentiation 163 (CD163) is the essential receptor for PRRSV infection. Metalloproteinase-mediated cleavage of CD163 leads to the shedding of soluble CD163 (sCD163), thereby inhibiting PRRSV proliferation. However, the exact cleavage site in CD163 and the potential role of sCD163 in inflammatory responses during PRRSV infection remain unclear. Herein, we found that PRRSV infection increased sCD163 levels, as demonstrated in primary alveolar macrophages (PAMs), immortalized PAM (IPAM) cell lines, and sera from PRRSV-infected piglets. With LC-MS/MS, Arg-1041/Ser-1042 was identified as the cleavage site in porcine CD163, and an IPAM cell line with precise mutation at the cleavage site was constructed. Using the precisely mutated IPAM cells, we found that exogenous addition of sCD163 protein promoted inflammatory responses, while mutation at the CD163 cleavage site suppressed inflammatory responses. Consistently, inhibition of sCD163 using its neutralizing antibodies reduced PRRSV infection-triggered inflammatory responses. Importantly, sCD163 promoted cell polarization from M2 to M1 phenotype, which in turn facilitated inflammatory responses. Taken together, our findings identify sCD163 as a novel proinflammatory mediator and provide valuable insights into the mechanisms underlying the induction of inflammatory responses by PRRSV infection.

Transcriptomic Analysis of Arachidonic Acid Pathway Genes Provides Mechanistic Insight into Multi-Organ Inflammatory and Vascular Diseases.

Arachidonic acid (AA) metabolites have been associated with several diseases across various organ systems, including the cardiovascular, pulmonary, and renal systems. Lipid mediators generated from AA oxidation have been studied to control macrophages, T-cells, cytokines, and fibroblasts, and regulate inflammatory mediators that induce vascular remodeling and dysfunction. AA is metabolized by cyclooxygenase (COX), lipoxygenase (LOX), and cytochrome P450 (CYP) to generate anti-inflammatory, pro-inflammatory, and pro-resolutory oxidized lipids. As comorbid states such as diabetes, hypertension, and obesity become more prevalent in cardiovascular disease, studying the expression of AA pathway genes and their association with these diseases can provide unique pathophysiological insights. In addition, the AA pathway of oxidized lipids exhibits diverse functions across different organ systems, where a lipid can be both anti-inflammatory and pro-inflammatory depending on the location of metabolic activity. Therefore, we aimed to characterize the gene expression of these lipid enzymes and receptors throughout multi-organ diseases via a transcriptomic meta-analysis using the Gene Expression Omnibus (GEO) Database. In our study, we found that distinct AA pathways were expressed in various comorbid conditions, especially those with prominent inflammatory risk factors. Comorbidities, such as hypertension, diabetes, and obesity appeared to contribute to elevated expression of pro-inflammatory lipid mediator genes. Our results demonstrate that expression of inflammatory AA pathway genes may potentiate and attenuate disease; therefore, we suggest further exploration of these pathways as therapeutic targets to improve outcomes.

Down-regulation of NF-κB signalling by methanolic extract of Viola odorata (L.) attenuated in vivo inflammatory and angiogenic responses.

Intractable inflammation plays a key role in the progression of autoimmune diseases such as rheumatoid arthritis. Oedema and angiogenesis are the hall marks of chronic inflammation. The current study was aimed to investigate the pharmacological effects of the methanolic extract of Viola odorata (Vo.Me)on inflammation induced oedema and angiogenesis, and to identify the active principles and explore the molecular mechanisms thereof. Various models of inflammation were utilized in rats, including carrageenan- and histamine-induced acute oedema, as well as chronic models of Complete Freund's Adjuvant (CFA)-induced arthritis and cotton pellet-induced granuloma. Anti-angiogenic activity was evaluated by CAM assay followed by quantification of phytoconstituents through HPLC.Effect ofVo.Me treatment on the expression of various mediators (PGE-2 andNO) and genes (IL-1β, TNF-α,NF-κB, and COX-2) were explored byqPCR and ELISA assays.HPLCanalysis showed the presence of quercetin, chlorogenic acid, gallic acid, benzoic acid, m-coumaric acid, p-coumaric acid, synergic acid, caffeic acid, vanillic acid, sinapic acid, and cinnamic acid in Vo.Me. Significant dose-dependent inhibition of rats' paw oedema was observed in the Vo.Me administered groups (p < 0.05)in both acute and chronic inflammatory models. Moreover, at a dosage of 500mg/kg, Vo.Me exhibited a comparable anti-inflammatory effect to indomethacin (p > 0.05). Additionally, Vo.Me demonstrated a remarkable anti-granulomatous activity. Histopathological findings demonstrated amelioration of inflammation in animal paws which were treated with Vo.Meand indomethacin. CAM assay also displayed significant inhibitory effect of Vo.Me on the blood vasculature growth. Vo.Me treatment also causedrelatively less gastric irritation and hepatic damage as compared toindomethacin.At amolecular level, thedown-regulation of NF-κB signalling leading tothedecreased activation of pro-inflammatory mediators (such as IL-1β, TNF-α, and COX-2) and their downstream molecules including prostaglandin E-2 (PGE-2) and nitric oxide (NO), is suggested to be responsible for these diverse anti-inflammatory effects. These findings confirmed the promising anti-inflammatory and anti-angiogenic activities of Vo.Me, which warrant bench-to-bedside translational studies to assess its safety and suitability for clinical usage.

Liver Fibrosis: From Basic Science towards Clinical Progress, Focusing on the Central Role of Hepatic Stellate Cells.

The burden of chronic liver disease is globally increasing at an alarming rate. Chronic liver injury leads to liver inflammation and fibrosis (LF) as critical determinants of long-term outcomes such as cirrhosis, liver cancer, and mortality. LF is a wound-healing process characterized by excessive deposition of extracellular matrix (ECM) proteins due to the activation of hepatic stellate cells (HSCs). In the healthy liver, quiescent HSCs metabolize and store retinoids. Upon fibrogenic activation, quiescent HSCs transdifferentiate into myofibroblasts; lose their vitamin A; upregulate α-smooth muscle actin; and produce proinflammatory soluble mediators, collagens, and inhibitors of ECM degradation. Activated HSCs are the main effector cells during hepatic fibrogenesis. In addition, the accumulation and activation of profibrogenic macrophages in response to hepatocyte death play a critical role in the initiation of HSC activation and survival. The main source of myofibroblasts is resident HSCs. Activated HSCs migrate to the site of active fibrogenesis to initiate the formation of a fibrous scar. Single-cell technologies revealed that quiescent HSCs are highly homogenous, while activated HSCs/myofibroblasts are much more heterogeneous. The complex process of inflammation results from the response of various hepatic cells to hepatocellular death and inflammatory signals related to intrahepatic injury pathways or extrahepatic mediators. Inflammatory processes modulate fibrogenesis by activating HSCs and, in turn, drive immune mechanisms via cytokines and chemokines. Increasing evidence also suggests that cellular stress responses contribute to fibrogenesis. Recent data demonstrated that LF can revert even at advanced stages of cirrhosis if the underlying cause is eliminated, which inhibits the inflammatory and profibrogenic cells. However, despite numerous clinical studies on plausible drug candidates, an approved antifibrotic therapy still remains elusive. This state-of-the-art review presents cellular and molecular mechanisms involved in hepatic fibrogenesis and its resolution, as well as comprehensively discusses the drivers linking liver injury to chronic liver inflammation and LF.

Understanding the Foreign Body Response via Single-Cell Meta-Analysis.

Foreign body response (FBR) is a universal reaction to implanted biomaterial that can affect the function and longevity of the implant. A few studies have attempted to identify targets for treating FBR through the use of single-cell RNA sequencing (scRNA-seq), though the generalizability of these findings from an individual study may be limited. In our study, we perform a meta-analysis of scRNA-seq data from all available FBR mouse studies and integrate these data to identify gene signatures specific to FBR across different models and anatomic locations. We identify subclusters of fibroblasts and macrophages that emerge in response to foreign bodies and characterize their signaling pathways, gene ontology terms, and downstream mediators. The fibroblast subpopulations enriched in the setting of FBR demonstrated significant signaling interactions in the transforming growth factor-beta (TGF-β) signaling pathway, with known pro-fibrotic mediators identified as top expressed genes in these FBR-derived fibroblasts. In contrast, FBR-enriched macrophage subclusters highly expressed pro-fibrotic and pro-inflammatory mediators downstream of tumor necrosis factor (TNF) signaling. Cell-cell interactions were additionally interrogated using CellChat, with identification of key signaling interactions enriched between fibroblasts and macrophages in FBR. By combining multiple FBR datasets, our meta-analysis study identifies common cell-specific gene signatures enriched in foreign body reactions, providing potential therapeutic targets for patients requiring medical implants across a myriad of devices and indications.

The wide spectrum anti-inflammatory activity of andrographolide in comparison to NSAIDs: A promising therapeutic compound against the cytokine storm.

The challenges of the COVID-19 pandemic have highlighted an increasing clinical demand for safe and effective treatment options against an overzealous immune defence response, also known as the "cytokine storm". Andrographolide is a naturally derived bioactive compound with promising anti-inflammatory activity in many clinical studies. However, its cytokine-inhibiting activity, in direct comparison to commonly used nonsteroidal anti-inflammatory drugs (NSAIDs), has not been extensively investigated in existing literature. The anti-inflammatory activities of andrographolide and common NSAIDs, such as diclofenac, aspirin, paracetamol and ibuprofen were measured on lipopolysaccharide (LPS) and interferon-γ induced RAW264.7 cells. The levels of PGE2, nitric oxide (NO), TNF-α & LPS-induced release of pro-inflammatory cytokines on differentiated human macrophage THP-1 cells were measured against increasing concentrations of andrographolide and aforementioned NSAIDs. The associated mechanistic pathway was examined on NFκB using flow cytometry on the human endothelial-leukocyte adhesion molecule (ELAM9) (E-selectin) transfected RAW264.7 cells with green fluorescent protein (GFP). Andrographolide exhibited broad and potent anti-inflammatory and cytokine-inhibiting activity in both cell lines by inhibiting the release of IL-6, TNF-α and IFN-γ, which are known to play a key role in the etiology of cytokine storm and the pathogenesis of inflammation. In comparison, the tested NSAIDs demonstrated weak or no activity against proinflammatory mediators except for PGE2, where the activity of andrographolide (IC50 = 8.8 μM, 95% CI = 7.4 to 10.4 μM) was comparable to that of paracetamol (IC50 = 7.73 μM, 95% CI = 6.14 to 9.73 μM). The anti-inflammatory action of andrographolide was associated with its potent downregulation of NFκB. The wide-spectrum anti-inflammatory activity of andrographolide demonstrates its therapeutic potential against cytokine storms as an alternative to NSAIDs.