Journal of Immunology Research

Group A Streptococcus (GAS), or Streptococcus pyogenes is almost exclusive and greatly adapted human pathogen. It causes a wide array of clinical symptoms, ranging from minor infections of the skin and soft tissues to pharyngitis, meningitis, pneumonia, bacteraemia, cellulitis, puerperal sepsis, and necrotising fasciitis. The risk of S. pyogenes infection is known to be influenced by several host characteristics, including age, underlying diseases like diabetes, varicella, or skin lesions, both chronic and acute, and certain risk behaviours such as use of drugs. Household size and overcrowding are two environmental factors that significantly affect the transmission of S. pyogenes. The majority of cases occur spontaneously in the community, and preventative opportunities are still limited. A large portion of GAS-related mortality is found in low-income areas and communities. Based on aforementioned public health risk, the creation of effective therapeutic vaccines would be an excellent addition to current control measures. The purpose of this work is to address the need for new instruments to aid in the elimination of S. pyogenes infections. The discovery of high antigenic regions in several highly conserved proteins brings us one step closer to developing peptide vaccines capable of influencing the different phases of S. pyogenes infection, providing more effective defence and greater serotype coverage. This study used various techniques of immunoinformatics to design an effective multi-epitope vaccine that produced neutralising antibodies against multiple strains of S. pyogenes.

Therapy of ischemic stroke is currently limited to pharmacological and/or mechanical recanalization. There are no neuroprotective therapies approved for use during the rehabilitative phase of ischemic stroke, which is characterized by neurodegenerative changes. Thus, the search for neuroprotective compounds capable of preventing neuronal death caused by pathogenetic cascades triggered during hypoxia is an urgent task. In this study, we demonstrate increased culture viability following pre- and post-incubation with salicyl-carnosine (SC) in a model of oxygen glucose deprivation on a primary culture of rat cortical neurons. Its neuroprotective properties were greater than that of acetylsalicylic acid and carnosine, and it was effective in lower concentrations. In addition, SC protected the culture from NMDA-induced excitotoxicity. We also showed the passage of SC into neurons, and the presence of its direct antioxidant activity in a model of paraquat-induced oxidative stress. The neuroprotective effects of SC are associated with a decrease in the level of pro-apoptotic protein Bak and a decrease in the activation of kinase p38, as well as an increase in the activation of kinase ERK1/2. The acquired data suggests that SC is a promising neuroprotective compound, and warrants further investigation in vivo.

Ivermectin is an important broad-spectrum anthelmintic used to treat nematode parasites including gastro-intestinal infections of humans and animals. The mode of action for Ivermectin is understood to involve activation of inhibitory glutamate-gated chloride channels (GluCls). Ivermectin has also been reported to inhibit the release of extracellular vesicles (EVs). We found that EVs are released from the whole intestine of the gastro-intestinal parasite, Ascaris suum. Proteomic analysis identified 1,574 proteins within these intestinal EVs, including 96 nematode proteins with putative immune-associated functions based on homology to proteins involved in host immune processes and 130 proteins with predicted digestive functions. Comparative analysis following ivermectin exposure revealed 38 differentially abundant proteins that included the putative immune-related proteins: transthyretin-like proteins, a small heat-shock antigen, a phospholipase A2, and the NF-{kappa}B subunit p105. Thus, ivermectin modulated the potential immune-related cargo of intestinal EVs. The ivermectin inhibition of intestinal EV release was concentration-dependent with an IC50 of 64 nM. We also identified the expression of GluCl subunit receptor genes in the Ascaris intestine. The potent inhibitory effect of ivermectin on the release of these EVs from the nematode intestine and the expression of GluCl channel subunits sheds further light on the site and mechanisms of action of this important anthelmintic.

RationaleNeurogenic inflammation is recognised as an important contributor to the pathophysiology of Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS). Substance P (Sub P), a neuropeptide released from sensory nerves, is a potent inducer of mast cell degranulation through the Mas-related G protein-coupled receptor member X2 (MRGPRX2), resulting in the release of pro-inflammatory mediators that perpetuate chronic bladder inflammation. Medihoney, a medical-grade M[a]nuka honey, possesses well-established antimicrobial and anti-inflammatory properties, and we have recently demonstrated its ability to stabilise mast cells through inhibition of histamine release. However, its effects on Sub P-induced mast cell activation and MRGPRX2-mediated neurogenic inflammation have not previously been investigated. Aim of the studyWe aimed to investigate the inhibitory effects of Medihoney and a sugar-free M[a]nuka honey extract on Substance P-induced mast cell degranulation and MRGPRX2 activation as potential therapeutic approaches for chronic neurogenic inflammation associated with IC/BPS. In addition, we examined the expression of MRGPRX2 in bladder biopsies from patients with IC/BPS. Materials and methodsHuman LAD2 mast cells were stimulated with Substance P (1 M) for 40 minutes following 20-minute pre-incubation with Medihoney or a sugar-free M[a]nuka honey extract. Mast cell degranulation was quantified by measuring {beta}-hexosaminidase release. MRGPRX2 activation was assessed by intracellular calcium imaging using Fluo-4 in MRGPRX2-expressing HEK-293 cells. Bladder biopsies obtained from patients with IC/BPS and healthy controls were immunostained for mast cell tryptase, chymase and MRGPRX2. ResultsMedihoney at 2% and 4% markedly inhibited Substance P-induced mast cell degranulation in LAD2 cells by approximately 90%, an effect that was similarly observed with the sugar-free M[a]nuka honey extract. Both preparations produced a dose-dependent inhibition of Substance P-induced intracellular signalling in MRGPRX2-expressing HEK-293 cells, demonstrating suppression of MRGPRX2 activation. Furthermore, immunohistochemical analysis of bladder biopsies revealed that approximately 66% of tryptase-positive mast cells expressed MRGPRX2 in patients with IC/BPS, which was significantly higher than that observed in healthy control tissues (25%). ConclusionThe present study demonstrates that mast cells within IC/BPS bladder tissue express increased levels of MRGPRX2, suggesting enhanced responsiveness to Substance P and supporting a role for neurogenic inflammation in the pathophysiology of IC/BPS. Medihoney and the sugar-free M[a]nuka honey extract significantly inhibit Substance P-induced mast cell degranulation through modulation of MRGPRX2-mediated intracellular signalling, highlighting their potential as novel therapeutic agents for reducing neurogenic bladder inflammation associated with IC/BPS. ImpactThis study provides evidence that MRGPRX2-mediated neurogenic mast cell activation is enhanced in IC/BPS and demonstrates, for the first time, that Medihoney and a sugar-free M[a]nuka honey extract effectively inhibit Substance P-induced mast cell degranulation through modulation of MRGPRX2 signalling. These findings provide new mechanistic insight into the anti-inflammatory actions of M[a]nuka honey-derived preparations and identify MRGPRX2 as a potential therapeutic target in IC/BPS. The observed inhibition of neurogenic mast cell activation suggests that these naturally derived preparations may offer a novel strategy for limiting chronic bladder inflammation. Overall, this work provides a foundation for future preclinical and clinical studies evaluating the safety and therapeutic efficacy of Medihoney and M[a]nuka honey-derived compounds in patients with IC/BPS.

Background: Gastric carcinoma remains a major cause of cancer related mortality worldwide, with tumor progression increasingly recognized as a consequence of complex interactions within the tumor microenvironment. Hypoxia induced signaling, cancer associated fibroblast (CAF) heterogeneity, and immune checkpoint activation play critical roles in tumor progression and immune evasion. However, their integrated relationship in gastric carcinoma remains insufficiently characterized. Objectives: To evaluate the expression of Hypoxia inducible factor 1 alpha and its association with cancer-associated fibroblast subtypes and Programmed death-ligand 1 expression in gastric carcinoma. Methods: This cross sectional analytical study included 100 histologically confirmed gastric carcinoma cases from Satkhira Medical College. Immunohistochemistry was performed for HIF 1 alpha, smooth muscle actin (SMA), fibroblast activation protein (FAP), and PD L1. CAFs were subclassified into myofibroblastic CAFs (myCAFs) and inflammatory CAFs (iCAFs). Associations between biomarkers and clinicopathological variables were analyzed using chi square test, Spearman correlation, and multivariate logistic regression. Receiver operating characteristic (ROC) curve analysis was used to assess model performance. Result: High HIF 1 alpha expression was observed in 55% of cases and demonstrated significant association with poor differentiation (p = 0.001), advanced tumor stage (p = 0.002), and lymph node metastasis (p = 0.001). iCAF predominance was significantly associated with poor differentiation (p = 0.003), advanced stage (p = 0.004), and nodal metastasis (p = 0.004). High PD L1 expression was significantly associated with poor differentiation (p = 0.03), advanced stage (p = 0.001), and lymph node metastasis (p = 0.002). Multivariate logistic regression identified high HIF 1 alpha expression (OR = 3.8, p = 0.001), iCAF dominance (OR = 4.5, p < 0.001), and advanced tumor stage (OR = 2.9, p = 0.004) as independent predictors of high PD L1 expression. Combined high HIF 1 alpha expression and CAF activation demonstrated the highest rate of PD L1 positivity (76.7%, p < 0.001). ROC curve analysis demonstrated good predictive performance of the model with an area under the curve of 0.81. Conclusion: The present study demonstrates a significant interaction between hypoxia, stromal remodeling, and immune checkpoint activation in gastric carcinoma. High HIF 1 alpha expression and inflammatory CAF predominance are strongly associated with aggressive clinicopathological features and increased PD L1 expression, supporting the existence of a coordinated hypoxia stroma immune axis in gastric carcinoma progression. These findings may have potential implications for prognostic stratification and combined targeted therapeutic strategies.

Endophytic fungi associated with the Himalayan yew (Taxus wallichiana) represent an underexplored source of bioactive secondary metabolites. This study investigated the extracellular metabolites of Annulohypoxylon purpureonitens isolated from Nepalese T. wallichiana using bioactivity screening combined with LCMS/MS-based metabolomics. The fungal extract exhibited broad-spectrum antibacterial activity, showing the strongest inhibition against Staphylococcus aureusand Enterococcus faecalis (MIC = 500 ug/mL). It also displayed notable antioxidant capacity(DPPH, ABTS, TPC &TFC) and cytotoxicity against HeLa and MCF-7 cancer cell lines. Metabolite profiling via GNPS molecular networking, manual MS/MS validation, and MASST reverse metabolomics putatively identified diverse compounds, including hydroquinidine, chlorogenic acid, muramic acid, and cordycepin conjugates widely distributed across public microbial datasets. Overall, A. purpureonitens is a promising source of multifunctional metabolites, laying a foundation for future compound isolation and functional characterization.

Transient receptor potential vanilloid 4 (TRPV4) is a Ca2+-permeable non-selective cation channel and its activating stimuli include anandamide, bisandrographolide, citric acid, arachidonic acid metabolic products by epoxygenases, hypo-osmotic cell swelling, and warm temperature. TRPV4 is involved in Ca2+-dependent signal transduction in several tissues. Since the activation of TRPV4 facilitates adherens junction formation in the skin epithelium, compounds that activate TRPV4 are expected to maintain or improve the barrier function of epidermal cells. In this study, we found that the extract of Arachis hypogaea (A. hypogaea) activate human TRPV4 (hTRPV4). In the Ca2+-imaging experiment, the application of A. hypogaea extract exhibited an increase in intracellular Ca2+ concentration ([Ca2+]i) in HEK293T cells expressing hTRPV4. The [Ca2+]i increases by application of A. hypogaea extract were not observed in HEK293T cells expressing hTRPV1, mouse TRPV2, hTRPV3, hTRPM8, or hTRPA1. We then examined the physicochemical properties of the components responsible for TRPV4 activation. Ethanol extracts of A. hypogaea caused an increase in [Ca2+]i in hTRPV4-expressing HEK293JN cells, whereas water, chloroform, and hexane extracts showed no activity. Moreover, the application of A. hypogaea extract enhanced transepithelial electrical resistance in the keratinocyte monolayer. These results suggest that A. hypogaea extract may contribute to the maintenance and improvement of the epidermal barrier function.

Severe dengue can damage the liver through unestablished mechanisms. We investigated the role of myeloperoxidase (MPO), a neutrophil enzyme, in dengue through patients, fatal liver samples, and mouse infection models. Observations from two independent clinical cohorts revealed elevated plasma MPO levels in dengue and, in one cohort, MPO was further linked to liver injury markers during the critical phase of disease, whereas livers from dengue fatal cases revealed MPO build-up in the vicinity of CD177+ activated neutrophils. In mice, dengue led to MPO overexpression, oxidative damage, and broad activation of innate and systemic inflammatory pathways in livers. Blocking MPO activity alleviated these and improved survival in one model and delayed disease progression without preventing death in another. These findings establish MPO as a functional mediator of severe dengue-associated liver injury and inflammation, which warrants further preclinical investigation into its hepatic pathogenic mechanism and its validity as target for therapeutic intervention.

Inflammatory bowel disease (IBD) is associated with chronic intestinal inflammation and gut microbial dysbiosis, yet effective microbiome-targeted therapeutics remain limited. Here, we investigated the anti-inflammatory and microbiome-modulating activities of metabolites isolated from Garcinia brassii, an endemic species of the Australian Wet Tropics. Five compounds, including a new natural product named garcitine, were isolated and structurally characterised. In human immune cells, garcinol and garcinia biflavonoid 1 significantly suppressed lipopolysaccharide-induced production of IL-1{beta}, IL-6, and TNF without detectable cytotoxicity, while parvifoliol F selectively inhibited IL-1{beta} release. Therapeutic efficacy was further evaluated in a TNBS-induced murine colitis model, where garcinia biflavonoid 1 and parvifoliol F significantly reduced colonic inflammation and improved histopathological outcomes. 16S rRNA sequencing demonstrated that both compounds restored gut microbial homeostasis by reversing colitis-associated dysbiosis and reducing inflammation-associated microbial signatures. Functional pathway prediction further suggested suppression of pro-inflammatory microbial metabolic pathways following treatment. Together, these findings demonstrate that Garcinia-derived metabolites alleviate experimental colitis through coordinated immunomodulatory and microbiome-reprogramming mechanisms and identify garcinia biflavonoid 1 and parvifoliol F as promising candidates for microbiome-targeted IBD therapeutics.

Osteoarthritis is characterized by inflammation, chondrocyte dysfunction, and progressive cartilage degradation. Boric acid (BA), a physiologically relevant boron compound, has shown anti-inflammatory properties, but its effects on human articular chondrocytes remain unclear. This study investigated whether BA could protect primary human chondrocytes against lipopolysaccharide-induced inflammatory injury. Cell survival, membrane damage, apoptosis, inflammatory mediator production, and expression of genes related to inflammation and extracellular matrix degradation were assessed. BA improved chondrocyte survival and reduced membrane damage and apoptosis following inflammatory stimulation. It also suppressed inflammatory and matrix-degrading gene expression, nitrite production, and the release of proinflammatory mediators. These protective effects were generally more pronounced with the higher treatment dose. Analysis of publicly available human chondrocyte RNA-sequencing datasets provided complementary support for the relevance of several investigated inflammatory and catabolic targets. Overall, these findings demonstrate that BA protects primary human chondrocytes against inflammatory and catabolic injury and support its further investigation as a potential chondroprotective approach in osteoarthritis.

Antibodies exhibit species-specific sequence and structural features that influence their antigen-recognition properties. Although several studies have investigated porcine antibodies, their repertoire and structural characteristics remain less well characterized than those of several other mammalian species. In this study, we analyzed public porcine heavy-chain repertoire sequencing data together with available antibody structural data to identify characteristic features of porcine antibodies. We found several residues enriched in porcine antibody framework regions, particularly at the base of heavy-chain complementarity-determining region 3 (CDR-H3). In particular, Arg101 and Glu123 were closely positioned in available structures and may influence CDR-H3 conformation at its base, whereas Pro120 may help constrain local backbone conformation. We also observed non-canonical cysteine usage in both framework region 1 and CDR-H3, which may contribute to structural diversity in the porcine repertoire. Finally, we evaluated the humanization potential of a porcine antibody using a human antibody language model and found that human-likeness increased after model-guided substitutions, although the resulting sequences did not exceed the T20 score threshold. Overall, these results indicate that porcine antibodies possess distinct sequence and structural features that may influence CDR-H3 properties and should be considered in future antibody analysis and engineering.

The rapid advancement of computational methods is transforming vaccine development by enabling faster, data-driven identification of promising antigens. In this study, we applied an in-silico pipeline to assess a broad set of sequence, structure, localisation, and immunology-derived features and determine which most effectively discriminate antigens from non-antigens in bacteria. Using these insights, we identified bacterial proteins with high potential as vaccine antigens. Applied to Staphylococcus aureus, this approach prioritized 304 candidate antigens, highlighting SSLs, nutrient acquisition factors, and cell wall-associated enzymes. While these findings demonstrate the potential of bioinformatics-guided antigen discovery, experimental validation remains essential. This work underscores the growing role of integrated computational and machine-learning approaches in accelerating next-generation vaccine design.

Enteric infections caused by Salmonella enterica remain a major global health concern and are increasingly associated with antimicrobial resistance. Therefore, new strategies to combat this important pathogen are needed. The interactions between S. enterica and the human host have been the subject of intense investigation over the last several decades, yet new findings continue to emerge. We previously showed that 15-deoxy-{Delta}12,14-prostaglandin J2 (15d-PGJ2) reduces Salmonella colonization of macrophages, but the mechanisms underlying this protective effect were still unknown. Here, we demonstrate that 15d-PGJ2 limits Salmonella infection by suppressing TLR4 signaling and inflammasome activation. Treatment with 15d-PGJ2 reduced TLR4 expression, NF-{kappa}B activation, iNOS, COX-2, nitric oxide production, IL-1{beta} release, and inflammasome-related targets, including NLRP3 and caspase-1 activity, while only partially reversing macrophage polarization. Combined treatment with the TLR4 antagonist TAK-242 further reduced bacterial colonization of and IL-1{beta} release by macrophages, supporting the involvement of TLR4 signaling in the effects of 15d-PGJ2. During mouse infections, 15d-PGJ2 reduced bacterial burdens in a tissue-dependent manner. Together, these findings demonstrate that 15d-PGJ2 limits Salmonella infection through selective modulation of TLR4 signaling and inflammasome activation.

L-Serine is an important metabolic and immunomodulatory biomolecule with promising role in managing infections, and autoimmune diseases. L-Serine provides the energy requirements and triggers the toll-like receptor signalling collaterally. However, the role of L-Serine in host antimicrobial response against Mycobacterium tuberculosis (Mtb) remains unexplored. In this study, we investigated whether this metabolite could modulate the antibiotics efficacy against Mtb. Although L-Serine exhibits limited intrinsic anti-mycobacterial activity, but L-Serine demonstrates a synergistic effect when combined with rifampicin and moxifloxacin against both drug-sensitive and multidrug-resistant Mtb. Moreover, L-Serine particularly in combination with palmitic acid showed the enhanced intracellular bacterial clearance in a dose- and time-dependent manner in murine and human macrophages. This synergistic effect was accompanied by increased nitric oxide production and modulation of the host immune response. We identified elevated levels of pro-inflammatory cytokines and reduced IL-10 expression. Furthermore, the metabolic supplementation demonstrated enhanced antimicrobial activity in isolated primary CD14+ monocytes from TB patients. Similarly, the metabolic supplementation of L-Serine in combination with isoniazid and rifampicin significantly reduced bacterial burdens in the lungs and spleen, while improving tissue architecture in murine infection model. Our observations suggest that L-Serine contributes to the observed therapeutic effects. Collectively, this study concludes that L-Serine acts as a promising host-directed therapeutic adjunct, which enhances antimicrobial immunity and potentiating antibiotic efficacy, providing a potential strategy for improving tuberculosis treatment outcomes.

Hemochromatosis and hemosiderosis are iron overload disorders that cause immune dysfunction and increase susceptibility to bacterial infections. There have been numerous case studies reporting septic-like outcomes for hemochromatosis patients infected with enteric Yersiniae; however, research regarding hemosiderosis and Yersinia infection is limited. Here, we have established a mouse model of hemosiderosis by feeding C57BL/6 mice a high-iron diet. These mice exhibit several indicators of iron overload that are seen clinically, including elevated serum iron levels and iron deposition in various tissues. Characterization of the iron overload mouse model shows that a high-iron diet induces local inflammation in the small intestine and systemic inflammation in a time-dependent manner. Oral infection with Yersinia enterocolitica causes complete mortality in the iron-overloaded mice, while wild-type mice all survive and effectively clear the infection. Lastly, we have observed that iron chelation therapies such as Deferoxamine and Deferisarox are detrimental to iron-overloaded mice during Yersinia infection. This work provides a model to further study iron overload disorders and Yersinia infection.

Production of aberrant glycans by cancer cells constitutes a key immunosuppressive strategy to avoid destruction by immune cells. Although sialic acid-containing glycans are known to dampen the activation of lymphocytes, including Natural Killer (NK) cells, the role of fucose-containing glycans remains poorly characterized. In this work, we explored the role of Lewis X (LeX) in cancer cell-NK cell interactions. We induced ectopic expression of FUT9, an 1-3/4-fucosyltransferase, in two colorectal cancer cell lines and showed this enzyme only synthesized LeX structures but not sialyl-LeX. FUT9 introduction was not associated with altered MHC class I surface expression, nor with CD2 (which has been proposed as a receptor for LeX) binding to cancer cells. By inhibiting fucosylation we could demonstrate that CD2 binding was furthermore independent of surface fucosylated glycans in three independent cell lines. Lastly, FUT9/LeX had a limited role in cancer cell destruction and expression of activation markers by NK cells. Overall, our study suggests that, unlike sialylated glycans, 1-3/4-fucosylated glycans have limited impact on cancer cell evasion of NK cell-mediated destruction.

Cigarette smoke-induced lung inflammation is a central driver of pulmonary diseases. The limited efficacy of current anti-inflammatory agents underscores the need for structurally novel therapeutics with distinct mechanisms. We recently demonstrated that AB-free kava, a flavokavains A/B-depleted formulation from Piper methysticum containing six major kavalactones, effectively suppresses cigarette smoke-induced lung inflammation in mice. This study aims to identify the bioactive constituent(s) and elucidate underlying mechanisms. These kavalactones revealed a clear structure-activity relationship in suppressing lipopolysaccharide (LPS)-stimulated prostaglandin E2 (PGE2) production in macrophages with desmethoxyyangonin (DMY) as the most potent kavalactone whereas dihydrokavain (DHK, a structurally similar analog) with minimal activity. DMY also effectively reduced LPS-induced interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-) production while DHK was ineffective. Mechanistically, DMY, but not DHK, attenuated COX-2 induction and reduced phosphorylation of cAMP response element-binding protein (CREB). Pharmacological inhibition of protein kinase A (PKA) similarly reduced p-CREB, COX-2 and PGE2, supporting a PKA-dependent CREB/COX-2 signaling in mediating PGE2 suppression while these effects were independent of nuclear factor kappa B (NF-{kappa}B) and activator protein 1 (AP-1) signaling. Similar results were observed for DMY and DHK in attenuating cigarette smoke condensate-induced proinflammatory pathways and PGE2 production. Consistently, DMY demonstrated significant in vivo efficacy in suppressing cigarette smoke-induced lung inflammation while DHK was not effective. Interestingly, dihydromethysticin (DHM) demonstrated the greatest in vivo anti-inflammatory efficacy, although it only exhibited moderate in vitro potency, likely due to its superior bioavailability over DMY. Concordantly, cigarette smoke exposure elevated p-CREB and COX-2 expressions in mouse lungs, which were attenuated by AB-free kava and its bioactive kavalactones with the extent of suppression correlating with their in vivo anti-inflammatory efficacy. DHM effectively suppressed LPS-induced neutrophil accumulation in mouse lungs as well. Collectively, these studies identify bioactive kavalactones in AB-free kava that suppress cigarette smoke- and LPS-induced lung inflammation through the modulation of the PKA/CREB/COX-2 signaling axis, providing a foundation for developing structurally distinct anti-inflammatory agents, particularly targeting smoke-induced inflammation and associated pulmonary diseases.

Several potentially potent anticancer drugs have been identified by in vitro evaluation, such as Andrographolide. These compounds show strong anticancer activity in vitro, but struggle to reach effective concentrations in the bloodstream when taken orally because they dissolve poorly in water or break down rapidly in the body. Bioenhancers, which are compounds that have potential to improve drug stability in the body, offer an alternative solution to overcome this limitation. Naringin and Quercetin have been identified as candidate bioenhancers, and have been hypothesized to potentially slow rapid first pass metabolism of poorly bioavailable drugs. Our work focuses on testing Naringin and Quercetin because they are flavonoids with therapeutic potential, due to their anti-inflammatory and antioxidant properties. Data from the hepatic microsomal assays performed on Naringin and Quercetin suggest moderate to proficient periods of stability in the body, with Naringin having 91.86% remaining, while Quercetin had 74.84% remaining. When administered alongside Andrographolide, a drug known to rapidly degrade in the body, Naringin raised its metabolic stability from 38.93% to 80.77% and on the other hand, Quercetin raised Andrographolide metabolic stability from 38.93% to 86.70%. In addition, plasma protein binding assays show the percentage of compounds available at the target site where Naringin was observed to be 49.32% bound and Quercetin found to be 50.14% bound, implying 50.68% of Naringin, and 49.86% of Quercetin available at the target site, respectively. This preliminary study explores whether Quercetin and Naringin could act as bioenhancers by remaining stable and available in plasma and by slowing the metabolism of poorly bioavailable drugs such as Andrographolide.

Introduction: Osteoarthritis (OA) is a degenerative joint condition characterized by chronic pain and the need for pain management. Locally targeting the endocytotic AP2 complex in nociceptors presents a potential strategy for providing sustained pain relief in individuals with OA. Objective: We investigated whether pain behavior associated with OA can be mitigated by genetically silencing the AP2alpha2 subunit of the AP2 complex in nociceptors and by pharmacologically inhibiting the AP2 complex through the intraarticular administration of a small lipidated decoy peptide. Method: Monoiodoacetate (MIA) was employed to induce knee joint OA in mice and rats. Pain behavior was assessed using dynamic weight-bearing and von Frey filaments. Upon confirmation of established OA pain behavior, in vivo AP2alpha2 genetic knockdown in mice was achieved through sciatic nerve transfection of a targeting AP2alpha2 short hairpin RNA (shRNA). To pharmacologically target endocytosis, a single intraarticular injection of peptide was administered into the arthritic knee of rats. The injection contained either the AP2 inhibitor peptide or a scrambled peptide control. Results: Pain behavior was significantly reduced after both genetic and pharmacological disruption of AP2-driven endocytosis. Animals treated with the Ap2 inhibitor peptide exhibited reduced pain behavior throughout the 28-day assay period. Following the completion of behavioral testing, arthritic knee joints and contralateral healthy knee joints were subsequently collected to assess the impact of the treatment on disease progression. Micro-computed tomography analysis revealed a preservation of bone volume in the arthritic joints that received the AP2 inhibitor peptide treatment, in contrast to the scrambled peptide group. Conclusion: These findings demonstrate that the inhibition of nociceptor endocytosis by a small lipidated peptide presents a promising approach to provide sustained relief from joint pain in individuals with arthritis.

BackgroundAsthma exacerbations are caused by dysregulated cellular interactions between airway and immune cell populations. Circulating microRNAs (miRNAs) are potential biomarkers for asthma exacerbations; however, their target airway cells remain poorly defined. ObjectiveTo identify the cell types that are regulated by the circulating microRNAs linked to asthma exacerbations and the extent to which the cells are regulated by miRNAs. MethodsWe integrated a curated panel of exacerbation-associated circulating miRNAs with single-cell RNA sequencing (scRNA-seq) profiles from induced sputum of 16 asthma patients and 8 healthy controls. Experimentally validated miRNA-target interactions were combined with cell-type-specific differential expression. Elastic Net regression and SHAP analysis quantified gene-level regulatory contributions, yielding a composite Regulation Strength metric. Findings were validated against four independent GEO datasets. ResultsImmune cells, including monocytes, dendritic cells, and macrophages, demonstrated the strongest statistically significant miRNA regulatory signals, in contrast to airway epithelial cells.hsa-miR-222-3p showed opposing regulatory effects in mature versus alveolar macrophages, indicating differentiation-state-dependent activity, while B_Plasma cells showed no detectable regulatory effect from any miRNA tested. Independent GEO validation confirmed higher expression of protective miRNAs (hsa-miR-126-3p, hsa-miR-146b-5p) in healthy individuals, consistent with prior CAMP cohort associations. ConclusionCirculating miRNAs show cell-type-specific regulatory activity, strongest in monocytes, dendritic cells, and macrophages. hsa-miR-222-3p showed opposing regulatory directions between macrophage subtypes, while B_Plasma cells showed no effect, validated across independent GEO cohorts.