Reduced Neutrophil Infiltration Research Articles

Evaluating the therapeutic potential of different sources of mesenchymal stem cells in acute respiratory distress syndrome

BackgroundMesenchymal stem/stromal cells (MSCs) have attracted interest as a potential therapy given their anti-inflammatory and immunomodulatory properties. However, clinical trials using MSCs for acute respiratory distress syndrome (ARDS) have produced mixed and inconclusive data. In previous work, we performed a “head-to-head” comparison between different sources of MSCs and showed that each source had a unique genomic and proteomic “signature”.MethodThis study investigated which sources of MSC: bone marrow derived-MSCs (BM-MSCs), adipose tissue derived-MSCs (AD-MSCs) and umbilical cord derived-MSCs (UC-MSCs) would be the optimal candidate to be used as a therapy in an LPS-induced mouse model of ARDS. Immune cells assessment, tissue transcriptomics, animal survival, and endothelial-epithelial barrier assessment were used to evaluate their effects.ResultsWhen comparing the three most commonly used MSC sources, we found that UC-MSCs exhibited greater efficacy compared to other MSCs in improving animal survival, mitigating epithelial/endothelial damage, decreasing lung inflammation via reducing neutrophil infiltration, T cell proliferation, and M1 polarization. Bulk RNA sequencing of lung tissue also showed that UC-MSCs have the capability to downregulate extracellular trap formation, by the downregulation of key genes like Elane and Padi4. Notably, treatment with UC-MSCs demonstrated a significant reduction in Fc-γ R mediated phagocytosis, which has been associated with monocyte pyroptosis and intense inflammation in the context of COVID-19.ConclusionOur findings suggest that UC-MSCs are an optimal source of MSC to treat acute inflammatory conditions in the lungs, such as ARDS.

Transcutaneous auricular vagus nerve stimulation mitigates gouty inflammation by reducing neutrophil infiltration in BALB/c mice

Gouty inflammation, caused by uric acid crystal deposition, primarily affects tissues around the toe joints and triggers potent inflammatory responses. Current treatments focus on alleviating inflammation and pain using pharmaceutical agents, which can lead to side effects and complications. This has generated interest in non-pharmacological interventions, such as non-invasive vagus nerve stimulation (VNS). In this study, we explored the anti-inflammatory mechanisms of transcutaneous auricular vagus nerve stimulation (taVNS) in a mouse model of acute gout. Gouty inflammation was induced by injecting monosodium urate (MSU) crystals into the ankle joints of BALB/c mice. The effects of taVNS on the expression of inflammatory cytokines and chemokines in the ankle joint tissue were assessed using real-time quantitative PCR (qPCR), western blotting, histological assessments (H&E staining), and immunohistochemistry (IHC). The role of α7 nicotinic acetylcholine receptors (α7nAChR) was also evaluated by signal blocking. Our findings revealed that MSU significantly elevated gout-associated inflammatory cascades and mediators in the ankle joint. Notably, taVNS at 200 µA and 25 Hz effectively reduced these inflammatory responses, decreasing neutrophil infiltration and chemoattraction within the tissue. taVNS showed significant anti-inflammatory properties by suppressing neutrophil activity, offering a novel therapeutic approach for gout beyond conventional pharmacological methods. Additionally, taVNS holds potential for managing various chronic joint diseases. These results highlight taVNS as a promising non-pharmacological therapy for chronic inflammation.

Phillyrin inhibits oxidative stress and neutrophil extracellular trap formation through the KEAP1/NRF2 pathway in gouty arthritis.

Gouty arthritis (GA) is an inflammatory disorder characterized by deposition of monosodium urate (MSU) crystal in joints. Phillyrin, a natural compound with anti-inflammatory properties, shows promise in mitigating inflammatory responses. This study investigates the therapeutic potential of phillyrin in GA and explores its mechanisms of action. GA was induced in mice via intraarticular MSU injection, and joint inflammation, inflammatory cell infiltration, and their level in serum/tissue were assessed. Key proteins in the NF-κB and NLRP3 pathways were examined using western blot analysis. The impact of phillyrin on oxidative stress, neutrophil extracellular trap (NET) formation, and neutrophil accumulation was evaluated by measuring CD11b + Ly6G + cells, MPO, CitH3, extracellular DNA ratio, and oxidative stress markers. In vitro studies assessed the effects of phillyrin on oxidative stress, cell viability, cytokine production, and NET formation in MSU-treated neutrophils. The KEAP1/NRF2 pathway's role was analyzed using ML385, an NRF2 inhibitor. Phillyrin significantly reversed MSU-induced ankle swelling and inflammatory cell infiltration in joint tissues. It suppressed pro-inflammatory cytokines and proteins in the NF-κB and NLRP3 pathways. Phillyrin reduced neutrophil infiltration, evidenced by lower MPO activity and NET formation, marked by reduced CitH3 expression. In vitro, phillyrin inhibited inflammatory marker expression and NET formation without affecting cell viability. It also restored antioxidant enzyme levels and reduced ROS production, regulating the KEAP1/NRF2 pathway, enhancing NRF2 expression and stability. These effects were reversed by NRF2 inhibition with ML385. Phillyrin alleviates GA by reducing joint inflammation, inhibiting NET formation, and suppressing oxidative stress through NRF2 modulation.

Quercetin alleviates liver fibrosis via regulating glycolysis of liver sinusoidal endothelial cells and neutrophil infiltration.

Liver fibrosis, a common characteristic in various chronic liver diseases, is largely influenced by glycolysis. Quercetin (QE), a natural flavonoid known to regulate glycolysis, was studied for its effects on liver fibrosis and its underlying mechanism. In a model of liver fibrosis induced by carbon tetrachloride (CCl4), we aimed to assess pathological features, serum marker levels, and analyze the expression of glycolysis-related enzymes at both mRNA and protein levels, with a focus on changes in liver sinusoidal endothelial cells (LSECs). Our results showed that QE effectively improved liver injury and fibrosis evident by improved pathological features and lowered levels of serum markers, such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), γ-glutamyl transferase (GGT), total bile acid (TBA), total bilirubin (TBIL), direct bilirubin (DBIL), hyaluronic acid (HA), laminin (LN), and procollagen type III (PCIII). QE also decreased lactate production and downregulated the expression of glycolysis-related enzymes-pyruvate kinase M2 (PKM2), phosphofructokinase platelet (PFKP), and hexokinase II (HK2)-at both the mRNA and protein levels. QE reduced the expression and activity of these enzymes, resulting in reduced glucose consumption, adenosine triphosphate (ATP) production, and lactate generation. Further analysis revealed that QE inhibited the production of chemokine (C-X-C motif) ligand 1 (CXCL1) and suppressed neutrophil recruitment. Overall, QE showed promising therapeutic potential for liver fibrosis by targeting LSEC glycolysis and reducing neutrophil infiltration.

Comparison of Dietary Supplementation with Krill Oil, Fish Oil, and Astaxanthin on an Experimental Ethanol-Induced Gastric Ulcer Model: A Biochemical and Histological Study

Background/Objectives: Despite advances in ulcer treatment research, the search for new, safe, and effective strategies for preventing and treating ulcer diseases persists. Methods: In this study, the protective effects of dietary supplementation with krill oil (KO), fish oil (FO), and astaxanthin (ASX) on an ethanol-induced gastric ulcer model were compared during biochemical and histological observations. Sprague–Dawley (n = 64) rats randomly divided into four groups—normal control (vehicle), KO, FO, and ASX groups—received the supplements via the orogastric route at a rate of 2.5% (v/w) of their daily feed consumption for 4 weeks. Then, ulcer induction was performed with ethanol. Results: The ulcer group showed increased levels of malondialdehyde (MDA), chemiluminescence (CL), and myeloperoxidase (MPO) activity and decreased levels of glutathione in the gastric tissues. While KO, FO, and ASX supplementation decreased chemiluminescence levels in the ulcer group, only ASX supplementation decreased MDA levels and MPO activity. Conclusions: In conclusion, supplementation with KO or FO has a similar protective effect against ethanol-induced ulcer damage, as it inhibits ROS formation and reduces lipid peroxidation. However, ASX supplementation has a higher protective effect than KO or FO supplementations against experimental ethanol-induced gastric lesions in rats, as it inhibits ROS formation and reduces neutrophil infiltration and lipid peroxidation.

The Role of Complement C1qa in Experimental Intracerebral Hemorrhage.

Evidence indicates that the complement system is activated and plays a role in brain injury after intracerebral hemorrhage (ICH). Most studies have focused on the role of C3, C5 and the membrane attack complex. The purpose of this study was to investigate the potential impact of complement C1q, a key upstream component of the classical pathway, on ICH-induced brain injury. Wild-type (WT) and C1qa knock out (KO) mice were compared using an autologous blood injection ICH model. Magnetic resonance imaging (MRI) was performed on days 1, 3 and 7 and brains harvested on days 3 and 7 for immunohistochemistry to examine brain injury mechanisms. WT and C1qa KO mice also received an intracerebral injection of thrombin, a key factor in ICH-induced brain injury. Following MRI scans, brains were harvested for immunohistochemistry on day 1. In comparison to WT mice, C1qa KO mice had reduced hematoma erythrolysis and neutrophil infiltration after ICH. However, they also had delayed hematoma clearance, which was associated with reduced induction of phagocytic multinuclear giant cells, and increased perihematomal neuronal damage. After thrombin injection, C1qa KO mice had smaller lesion volumes, less neuronal loss, reduced neutrophil infiltration, and less BBB damage. C1qa knockout has beneficial and detrimental effects on ICH-induced brain injury mechanisms, but a consistent beneficial effect after thrombin injection. Strategies to balance the roles of C1q after ICH may represent a promising therapeutic direction.

Synergistic potentiation of the anti-metastatic effect of a Ginseng-Salvia miltiorrhiza herbal pair and its biological ingredients via the suppression of CD62E-dependent neutrophil infiltration and NET formation.

The combination of the roots of ginseng and Salvia miltiorrhiza is an effective approach for treating metastatic cancer in patients with Qi stagnation and blood stasis patterns. However, the molecular mechanism underlying the combined use of ginseng and Salvia miltiorrhiza is unknown. This study unveils the pharmacological foundation of ginseng and Salvia miltiorrhiza by examining the involvement of neutrophils in the critical process of tumor hematogenous metastasis. Additionally, by employing a reverse pharmacology research model (effect-target-constituent), potential potent components were screened, and the dominant component formulations were determined. An experimental lung metastatic model was constructed to compare the antitumor effects of ginseng and Salvia miltiorrhiza. RNA sequencing was employed to identify pivotal biological events and key targets, while the detection of CD62E expression and neutrophil extracellular traps (NETs) release was used to screen for effective substances in ginseng and Salvia miltiorrhiza. In addition, a comprehensive array of in vitro and in vivo experiments was conducted to explore the underlying mechanisms and therapeutic significance. Compared with single-herb use, the use of ginseng or Salvia miltiorrhiza significantly reduced tumor metastasis, which was accompanied by reduced neutrophil infiltration into the lungs. Cryptotanshinone (CPT), an active constituent of Salvia miltiorrhiza, can inhibit neutrophil adhesion and recruitment to lung tissue by downregulating the expression of E-selectin (CD62E) in endothelial cells. Moreover, the ginseng -derived ginsenoside Rg1 mitigated the formation of NETs in lung tissues and reversed the protumor effects of NETs. We further explored the efficacy of combination therapy with Rg1 and CPT, which also reduced tumor metastasis in vivo. Ginseng and Salvia miltiorrhiza exhibited a mutual potentiation of the anti-metastatic effect by suppressing both early and late stages of neutrophil-initiated metastasis cascade. Rg1 and CPT represent the synergistic ingredients from ginseng and Salvia miltiorrhiza, respectively.

Knockout of neutrophil cytosolic factor 1 ameliorates neuroinflammation and motor deficit after traumatic brain injury

Traumatic brain injury (TBI) is a predominant cause of long-term disability in adults, yet the molecular mechanisms underpinning the neuropathological processes associated with it remain inadequately understood. Neutrophil cytosolic factor 1 (NCF1, also known as p47phox) is one of the cytosolic components of NADPH oxidase NOX2. In this study, we observed a reduction in the volume of TBI-induced brain lesions in NCF1-knockout mice compared to controls. Correspondingly, the neuronal loss induced by TBI was mitigated in the NCF1-knockout mice. Behavioral analysis also demonstrated that the motor coordination deficit following TBI was mitigated by the depletion of NCF1. Mechanistically, our findings revealed that NCF1 deficiency attenuated TBI-induced inflammatory responses by inhibiting the release of proinflammatory factors and reducing neutrophil infiltration into the brain parenchyma. Additionally, our results indicated that NCF1 deficiency significantly decreased the levels of reactive oxygen species in neutrophils. Taken together, our findings indicate that NCF1 plays a crucial role in the regulation of brain injury and secondary inflammation post-TBI.

Corynoline alleviates hepatic ischemia-reperfusion injury by inhibiting NLRP3 inflammasome activation through enhancing Nrf2/HO-1 signaling.

Corynoline has displayed pharmacological effects in reducing oxidative stress and inflammatory responses in many disorders. However, its effects on hepatic ischemia-reperfusion (I/R) injury remain unclear. This study aimed to investigate the protective effects of corynoline against hepatic I/R injury and the underlying mechanisms. Rat models with hepatic I/R injury and BRL-3A cell models with hypoxia/reoxygenation (H/R) insult were constructed. Models were pretreated with corynoline and/or other inhibitors for functional and mechanistic examination. Corynoline pretreatment effectively mitigated hepatic I/R injury verified by reduced serum transaminase levels, improved histological damage scores, and decreased apoptosis rates. Additionally, corynoline pretreatment significantly inhibited I/R-triggered oxidative stress and inflammatory responses, as indicated by enhanced mitochondrial function, reduced levels of ROS and MDA, reduced neutrophil infiltration and suppressed proinflammatory cytokine release. In vitro experiments further showed that corynoline pretreatment increased cellular viability, decreased LDH activity, reduced cellular apoptosis, and inhibited oxidative stress and inflammatory injury in H/R-induced BRL-3A cells. Mechanistically, corynoline significantly increased Nrf2 nuclear translocation and expression levels of its target gene, HO-1. It also blocked NLRP3 inflammasome activation both in vivo and in vitro. Furthermore, pretreatment with Nrf2 inhibitor ML-385 counteracted the protective effect of corynoline on hepatic I/R injury. Ultimately, in vitro studies revealed that the NLRP3 activator nigericin could also nullified the protective effects of corynoline in BRL-3A cells, but had minimal impact on Nrf2 nuclear translocation. Corynoline can exert protective effects against hepatic I/R injury by inhibiting oxidative stress, inflammatory responses, and apoptosis. These effects may be associated with inhibiting ROS-induced NLRP3 inflammasome activation by enhancing Nrf2/HO-1 signaling. These data provide new understanding about the mechanism of corynoline action, suggesting it is a potential drug applied for the treatment and prevention of hepatic I/R injury.

Licochalcone A Ameliorates Aspergillus fumigatus Keratitis by Reducing Fungal Load and Activating the Nrf2/HO-1 Signaling Pathway.

Fungal keratitis (FK) is a blinding corneal infectious disease. The prognosis is frequently unfavorable due to fungal invasion and an excessive host inflammatory response. Licochalcone A (Lico A) exhibits a broad spectrum of pharmacological activities, encompassing antifungal, anti-inflammatory, antioxidation, and antitumor properties. However, the role of Lico A has not yet been studied in FK. In this study, we discovered that Lico A could disrupt Aspergillus fumigatus (A. fumigatus) biofilms, inhibit fungal growth and adhesion to host cells, induce alterations of hyphal morphology, and impair the cell membrane and cell wall integrity and mitochondrial structure of A. fumigatus. Lico A can alleviate the severity of FK in mice, reduce neutrophil infiltration and fungal load, and significantly decrease the pro-inflammatory cytokines in mouse corneas infected with A. fumigatus. In vitro, we also demonstrated that Lico A increased the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) around the nucleus in human corneal epithelial cells (HCECs) stimulated with A. fumigatus. We verified that the anti-inflammatory effect of Lico A is associated with the activation of the Nrf2/HO-1 axis. These results indicated that Lico A could provide a protective role in A. fumigatus keratitis through its anti-inflammatory and antifungal activities.

Disruption of the PGE2 synthesis / response pathway restrains atherogenesis in programmed cell death-1 (Pd-1) deficient hyperlipidemic mice.

Immune checkpoint inhibitors (ICIs) that target programmed cell death 1 (PD-1) have revolutionized cancer treatment by enabling the restoration of suppressed T-cell cytotoxic responses. However, resistance to single-agent ICIs still limits their clinical utility. Combinatorial strategies enhance the antitumor effects, but may also enhance the risk of immune related adverse effects of ICIs. Prostaglandin (PG) E2, formed by the sequential action of the cyclooxygenase (COX) and microsomal PGE synthase (mPGES-1) enzymes, acting via its E prostanoid (EP) receptors, EPr2 and EPr4, promotes lymphocyte exhaustion, revealing an additional target for ICIs. Thus, COX inhibitors and EPr4 antagonists are currently being combined with ICIs potentially to enhance antitumor efficacy in clinical trials. However, given the cardiovascular (CV) toxicity of COX inhibitors, such combinations may increase the risk particularly of CV AEs. Here, we compared the impact of distinct approaches to disruption of the PGE2 synthesis /response pathway- global or myeloid cell specific depletion of mPges-1 or global depletion of Epr4- on the accelerated atherogenesis in Pd-1 deficient hyperlipidemic (Ldlr KO) mice. All strategies restrained the atherogenesis. While depletion of mPGES-1 suppresses PGE2 biosynthesis, reflected by its major urinary metabolite, PGE2 biosynthesis was increased in mice lacking EPr4, consistent with enhanced expression of aortic Cox-1 and mPges-1. Deletions of mPges-1 and Epr4 differed in their effects on immune cell populations in atherosclerotic plaques; the former reduced neutrophil infiltration, while the latter restrained macrophages and increased the infiltration of T-cells. Consistent with these findings, chemotaxis by bone-marrow derived macrophages from Epr4 KO mice as impaired. in Epr4 depletion also resulted in extramedullary lymphoid hematopoiesis and inhibition of lipoprotein lipase activity (LPL) with coincident spelenomegaly, leukocytosis and dyslipidemia. Targeting either mPGES-1 or EPr4 may restrain lymphocyte exhaustion while mitigating CV irAEs consequent to PD-1 blockade.

Therapeutic potential of Sertoli cells in vivo: alleviation of acute inflammation and improvement of sperm quality

BackgroundInflammation-induced testicular damage is a significant contributing factor to the increasing incidence of infertility. Traditional treatments during the inflammatory phase often fail to achieve the desired fertility outcomes, necessitating innovative interventions such as cell therapy.MethodsWe explored the in vivo properties of intravenously administered Sertoli cells (SCs) in an acute lipopolysaccharide (LPS)-induced inflammatory mouse model. Infiltrating and resident myeloid cell phenotypes were assessed using flow cytometry. The impact of SC administration on testis morphology and germ cell quality was evaluated using computer-assisted sperm analysis (CASA) and immunohistochemistry.ResultsSCs demonstrated a distinctive migration pattern, importantly they preferentially concentrated in the testes and liver. SC application significantly reduced neutrophil infiltration as well as preserved the resident macrophage subpopulations. SCs upregulated MerTK expression in both interstitial and peritubular macrophages. Applied SC treatment exhibited protective effects on sperm including their motility and kinematic parameters, and maintained the physiological testicular morphology.ConclusionOur study provides compelling evidence of the therapeutic efficacy of SC transplantation in alleviating acute inflammation-induced testicular damage. These findings contribute to the expanding knowledge on the potential applications of cell-based therapies for addressing reproductive health challenges and offer a promising approach for targeted interventions in male infertility.

Effects of the N-Butanol Extract of Pulsatilla Decoction on Neutrophils in a Mouse Model of Ulcerative Colitis.

Ulcerative colitis (UC) is a chronic inflammatory disease, the incidence of which is increasing worldwide. However, the etiology and pathogenesis of UC remains unclear. The n-butanol extract of Pulsatilla decoction (BEPD), a traditional Chinese medicine, has been shown to be effective in treating UC. This study aimed to explore the molecular mechanism underlying the effects of BEPD on UC, in particular its effects on neutrophil extracellular trap (NET) formation by neutrophils. High-performance liquid chromatography was used to determine the principal compounds of BEPD. UC was induced in mice using dextran sodium sulfate, and mice were treated with 20, 40, or 80 mg/kg BEPD daily for seven days. Colonic inflammation was determined by assessing the disease activity index, histopathology, colonic mucosal damage index, colonic mucosal permeability, and pro- and anti-inflammatory cytokine levels. The infiltration and activation status of neutrophils in the colon were determined by analyzing the levels of chemokine (C-X-C motif) ligand (CXCL) 1 and CXCL2, reactive oxygen species, Ly6G, and numerous NET proteins. The findings suggest that BEPD improved the disease activity index, histopathology, and colonic mucosal damage index scores of mice with UC, and restored colonic mucosal permeability compared with untreated mice. The expression levels of the pro-inflammatory cytokines interleukin-1β, interleukin-6, and tumor necrosis factor-α in colon tissues were significantly decreased, while the expression levels of anti-inflammatory cytokines in colon tissues were significantly increased, exceeding those of control mice. In addition, BEPD reduced the expression of the neutrophil chemokines CXCL1 and CXCL2 in the colon tissue of mice with UC, reduced neutrophil infiltration, reduced reactive oxygen species levels, and significantly reduced the expression of NET proteins. BEPD also significantly reduced NET formation. The results of this study suggest that BEPD exerts therapeutic effects in a murine model of UC by inhibiting neutrophil infiltration and activation in the colon, as well as by inhibiting the expression of key proteins involved in NET formation and reducing NET formation, thereby alleviating local tissue damage and disease manifestations.

Esculetin facilitates post-stroke rehabilitation by inhibiting CKLF1-mediated neutrophil infiltration.

Esculetin (ESC) is a coumarin-derived phytochemical prevalent in traditional Chinese medicine that exhibits anti-acute ischemic stroke activities. Our previous studies demonstrate that CKLF1 is a potential anti-stroke target for coumarin-derived compound. In this study we investigated whether CKLF1 was involved in the neuroprotective effects of ESC against photothrombotic stroke in mice. The mice were treated with ESC (20, 40 or 80 mg·kg-1·d-1, i.g.) for two weeks. The therapeutic effect of ESC was assessed using MRI, neurological function evaluation, and a range of behavioral tests on D1, 3, 7 and 14 of ESC administration. We showed that oral administration of ESC dose-dependently reduced the cerebral infarction volume within one week after stroke, improved behavioral performance, and alleviated neuropathological damage within two weeks. Functional MRI revealed that ESC significantly enhanced the abnormal low-frequency fluctuation (ALFF) value of the motor cortex and promoted functional connectivity between the supplementary motor area (SMA) and multiple brain regions. We demonstrated that ESC significantly reduced the protein levels of CKLF1 and CCR5, as well as the CKLF1/CCR5 protein complex in the peri-infarcted area. We showed that ESC (0.1-10 μM) dose-dependently blocked CKLF1-induced chemotactic movement of neutrophils in the Transwell assay, reducing the interaction of CKLF1/CCR5 on the surface of neutrophils, thereby reducing neutrophil infiltration, and decreasing the expression of ICAM-1, VCAM-1 and MMP-9 in the peri-infarct tissue. Knockout of CKLF1 reduced brain infarction volume and motor dysfunction after stroke but also negated the anti-stroke efficacy and neutrophil infiltration of ESC. These results suggest that the efficacy of ESC in promoting post-stroke neural repair depends on its inhibition on CKLF1-mediated neutrophil infiltration, which offering novel perspectives for elucidating the therapeutic properties of coumarins.

Leveraging thiol-functionalized biomucoadhesive hybrid nanoliposome for local therapy of ulcerative colitis

Directly administering medication to inflamed intestinal sites for treating ulcerative colitis (UC), poses significant challenges like retention time, absorption variability, side effects, drug stability, and non-specific delivery. Recent advancements in therapy to treat colitis aim to improve local drug availability that is enema therapy at the site of inflammation, thereby reducing systemic adverse effects. Nevertheless, a key limitation lies in enemas' inability to sustain medication in the colon due to rapid peristaltic movement, diarrhea, and poor local adherence. Therefore, in this work, we have developed site-specific thiolated mucoadhesive anionic nanoliposomes to overcome the limitations of conventional enema therapy. The thiolated delivery system allows prolonged residence of the delivery system at the inflamed site in the colon, confirmed by the adhesion potential of thiolated nanoliposomes using in-vitro and in-vivo models. To further provide therapeutic efficacy thiolated nanoliposomes were loaded with gallic acid (GA), a natural compound known for its antibacterial, antioxidant, and potent anti-inflammatory properties. Consequently, Gallic Acid-loaded Thiolated 2,6 DALP DMPG (GATh@APDL) demonstrates the potential for targeted adhesion to the inflamed colon, facilitated by their small size 100 nm and anionic nature. Therapeutic studies indicate that this formulation offers protective effects by mitigating colonic inflammation, downregulating the expression of NF-κB, HIF-1α, and MMP-9, and demonstrating superior efficacy compared to the free GA enema. The encapsulated GA inhibits the NF-κB expression, leading to enhanced expression of MUC2 protein, thereby promoting mucosal healing in the colon. Furthermore, GATh@APDL effectively reduces neutrophil infiltration and regulates immune cell quantification in colonic lamina propria. Our findings suggest that GATh@APDL holds promise for alleviating UC and addressing the limitations of conventional enema therapy.

Modulating the RPS27A/PSMD12/NF-κB pathway to control immune response in mouse brain ischemia-reperfusion injury

BackgroundInvestigating immune cell infiltration in the brain post-ischemia-reperfusion (I/R) injury is crucial for understanding and managing the resultant inflammatory responses. This study aims to unravel the role of the RPS27A-mediated PSMD12/NF-κB axis in controlling immune cell infiltration in the context of cerebral I/R injury.MethodsTo identify genes associated with cerebral I/R injury, high-throughput sequencing was employed. The potential downstream genes were further analyzed using Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Protein-Protein Interaction (PPI) analyses. For experimental models, primary microglia and neurons were extracted from the cortical tissues of mouse brains. An in vitro cerebral I/R injury model was established in microglia using the oxygen-glucose deprivation/reoxygenation (OGD/R) technique. In vivo models involved inducing cerebral I/R injury in mice through the middle cerebral artery occlusion (MCAO) method. These models were used to assess neurological function, immune cell infiltration, and inflammatory factor release.ResultsThe study identified RPS27A as a key player in cerebral I/R injury, with PSMD12 likely acting as its downstream regulator. Silencing RPS27A in OGD/R-induced microglia decreased the release of inflammatory factors and reduced neuron apoptosis. Additionally, RPS27A silencing in cerebral cortex tissues mediated the PSMD12/NF-κB axis, resulting in decreased inflammatory factor release, reduced neutrophil infiltration, and improved cerebral injury outcomes in I/R-injured mice.ConclusionRPS27A regulates the expression of the PSMD12/NF-κB signaling axis, leading to the induction of inflammatory factors in microglial cells, promoting immune cell infiltration in brain tissue, and exacerbating brain damage in I/R mice. This study introduces novel insights and theoretical foundations for the treatment of nerve damage caused by I/R, suggesting that targeting the RPS27A and downstream PSMD12/NF-κB signaling axis for drug development could represent a new direction in I/R therapy.

SFRP1 reduces neutrophil infiltration and inhibits the Wnt/β-catenin pathway to alleviate oral submucous fibrosis.

Oral submucous fibrosis (OSF) is a precancerous condition characterized by oral mucosal atrophy with fibrosis of the submucosal tissue. OSF has a high prevalence, and treatment requires improvement. Our study aims to investigate the role and mechanism of secreted frizzled-related protein 1 (SFRP1) in OSF. We constructed an arecoline-induced OSF mice model. Through Pearson's correlation analysis, we investigated the association between SFRP1 levels and expressions of proteins related to the Wnt/β-catenin signaling pathway, as well as the correlation between SFRP1 levels and the degree of neutrophil infiltration. Moreover, neutrophil infiltration intensity, tissue fibrosis degree, and levels of β-catenin, Cyclin D1, and c-myc were evaluated after SFRP1 overexpression treatment through immunohistochemical and biochemical assays. A Wnt/β-catenin pathway activator was used to investigate the molecular mechanism of SFRP1 in the arecoline-induced OSF cell model. Compared with the control group, mice in the OSF group exhibited increased collagen deposition and more severe fibrosis in the oral mucosal tissue (OMT). In the OMT of OSF mice, the levels of SFRP1 were decreased. The levels of SFRP1 exhibited a negative correlation with the levels of Wnt/β-catenin proteins and neutrophil infiltration in the OMT. Upon SFRP1 overexpression, there was a reduction in neutrophil infiltration and fibrosis in the OMT, as well as inhibition of Wnt/β-catenin-related proteins. In vitro, the Wnt/β-catenin pathway activator further reversed the effect of SFRP1 overexpression on OSF. SFRP1 attenuates OSF by reducing neutrophil infiltration and inhibiting the Wnt/β-catenin pathway.

Sophoricoside ameliorates methicillin-resistant Staphylococcus aureus-induced acute lung injury by inhibiting Bach1/Akt pathway

BackgroundThe lack of effective treatments for methicillin-resistant Staphylococcus aureus (MRSA) infection, which often leads to severe acute lung injury (ALI), poses a grave threat to human life. Sophoricoside (SOP), an isoflavone glycoside abundant in the fruit of traditional Chinese herbal Sophora japonica l., showed anti-inflammatory effects against atopic dermatitis, allergic inflammation, and lipopolysaccharide-induced ALI. However, its effect and underlying mechanism on MRSA-induced ALI remain unclear. PurposeThe aim of this study is to assess the protective effect of SOP in MRSA-induced ALI and elucidate its underlying molecular mechanisms. MethodsIn vivo experiments were conducted using wild-type mice to establish MRSA-induced ALI mouse model, and the effects of SOP on ALI were evaluated by hematoxylin-eosin staining, flow cytometry, quantitative real-time polymerase chain reaction, and several biochemical indicators. Adoptive transfer experiments and BTB and CNC homology 1 knockout (Bach1-/-) mice were also utilized in this study. In vitro studies employed murine macrophages RAW264.7 cells, primary bone marrow-derived macrophages (BMDMs), and primary lung macrophages to explore the underlying molecular mechanisms. ResultsThe administration of SOP ameliorated MRSA-induced ALI by improving pulmonary histological damages, reducing neutrophil infiltration, suppressing oxidative stress levels, and decreasing the expression of inflammatory cytokines. In isolation experiments with ALI mouse lung macrophages and macrophage adoptive transfer experiments, SOP prevented macrophage activation, thereby reducing the production of proinflammatory cytokines. In vitro experiments demonstrated that SOP decreased the expression of inflammatory mediators in lipoteichoic acid (LTA)-stimulated RAW264.7 cells, BMDMs, and primary lung macrophages. Additionally, SOP inhibited protein kinase B (Akt) phosphorylation and treatment with MK2206-a specific inhibitor of Akt-eliminated SOP's ability to suppress LTA-stimulated macrophage inflammation. Furthermore, stimulation with LTA or MRSA up-regulated Bach1 expression; however, deletion of Bach1 abolished the inhibitory effect of SOP on p-Akt activation as well as inflammation and ALI development. ConclusionThis study provides the first evidence that SOP effectively mitigates MRSA-induced ALI via suppressing macrophage activation through the inhibition of Bach1/Akt pathway. These findings highlight the potential of SOP as a novel therapeutic agent for treating MRSA-induced ALI.

Fucoidan as a Promising Drug for Pain Treatment: Systematic Review and Meta-Analysis.

Fucoidan is a polymer of L-fucose and L-fucose-4-sulphate naturally found in marine sources that inhibits p-selectin, preventing neutrophil recruitment to the site of injury. Fucoidan is employed in many studies as a tool to investigate the contribution of neutrophils to pain, showing analgesic effects. We performed a systematic review and meta-analysis to quantify the analgesic effects of pretreatment with fucoidan reported in the available preclinical studies. In addition, we summarized the articles which have studied the therapeutic effects of fucoidan in pathological pain at preclinical and clinical levels. The results of this systematic review reveal that pretreatment with fucoidan is a powerful tool which reduces neutrophil infiltration by 70-90% at early time points. This meta-analysis showed that preventative treatment with fucoidan produced a significant pain reduction. In addition, several preclinical studies have observed that fucoidan treatment reduces the pain that is associated with various pathologies. Finally, fucoidan has also been tested in several clinical trials, with some degree of analgesic efficacy, but they were mostly small pilot studies. Considering all the above information, it can be concluded that fucoidan is not only a preclinical tool for studying the role of neutrophils in pain but also a promising therapeutic strategy for pain treatment.

Exosomal miRNA-26b-5p from PRP suppresses NETs by targeting MMP-8 to promote diabetic wound healing

The utilization of platelet-rich plasma (PRP) has exhibited potential as a therapeutic approach for the management of diabetic foot ulcers (DFUs). However, it is currently not well understood how the diabetic environment may influence PRP-derived exosomes (PRP-Exos) and their potential impact on neutrophil extracellular traps (NETs). This study aims to investigate the effects of the diabetic environment on PRP-Exos, their communication with neutrophils, and the subsequent influence on NETs and wound healing. Through bulk-seq and Western blotting, we confirmed the increased expression of MMP-8 in DFUs. Additionally, we discovered that miRNA-26b-5p plays a significant role in the communication between DFUs and PRP-Exos. In our experiments, we found that PRP-Exos miR-26b-5p effectively improved diabetic wound healing by inhibiting NETs. Further tests validated the inhibitory effect of miR-26b-5p on NETs by targeting MMP-8. Both in vitro and in vivo experiments showed that miRNA-26b-5p from PRP-Exos promoted wound healing by reducing neutrophil infiltration through its targeting of MMP-8. This study establishes the importance of miR-26b-5p in the communication between DFUs and PRP-Exos, disrupting NETs formation in diabetic wounds by targeting MMP-8. These findings provide valuable insights for developing novel therapeutic strategies to enhance wound healing in individuals suffering from DFUs.