Inflammatory Injury Research Articles

Reactive oxygen species in hypertension.

Hypertension is a leading risk factor for stroke, heart disease and chronic kidney disease. Multiple interacting factors and organ systems increase blood pressure and cause target-organ damage. Among the many molecular elements involved in the development of hypertension are reactive oxygen species (ROS), which influence cellular processes in systems that contribute to blood pressure elevation (such as the cardiovascular, renal, immune and central nervous systems, or the renin-angiotensin-aldosterone system). Dysregulated ROS production (oxidative stress) is a hallmark of hypertension in humans and experimental models. Of the many ROS-generating enzymes, NADPH oxidases are the most important in the development of hypertension. At the cellular level, ROS influence signalling pathways that define cell fate and function. Oxidative stress promotes aberrant redox signalling and cell injury, causing endothelial dysfunction, vascular damage, cardiovascular remodelling, inflammation and renal injury, which are all important in both the causes and consequences of hypertension. ROS scavengers reduce blood pressure in almost all experimental models of hypertension; however, clinical trials of antioxidants have yielded mixed results. In this Review, we highlight the latest advances in the understanding of the role and the clinical implications of ROS in hypertension. We focus on cellular sources of ROS, molecular mechanisms of oxidative stress and alterations in redox signalling in organ systems, and their contributions to hypertension.

EPOS-OHCA: Early Predictors of Outcome and Survival after non-traumatic Out-of-Hospital Cardiac Arrest

BackgroundPost-cardiac arrest syndrome (PCAS) after out-of-hospital cardiac arrest (OHCA) poses significant challenges due to its complex pathomechanisms involving inflammation, ischemia, and reperfusion injury. The identification of early available prognostic indicators is essential for optimizing therapeutic decisions and improving patient outcomes. MethodsIn this retrospective single-center study, we analyzed real-world data from 463 OHCA patients with either prehospital or in-hospital return of spontaneous circulation (ROSC), treated at the Cardiac Arrest Center of the University Hospital of Marburg (MCAC) from January 2018 to December 2022. We evaluated demographic, prehospital, and clinical variables, including initial rhythms, resuscitation details, and early laboratory results. Statistical analyses included logistic regression to identify predictors of survival and neurological outcomes. ResultsOverall, 46.9% (n = 217) of patients survived to discharge, with 70.1% (n = 152) achieving favorable neurological status (CPC 1 or 2). Age, initial shockable rhythm, resuscitation time to return of spontaneous circulation (ROSC), and early laboratory parameters like lactate, C-reactive protein, and glomerular filtration rate were identified as independent and combined Early Predictors of Outcome and Survival (EPOS), with high significant predictive value for survival (AUC 0.86 [95% CI 0.82–0.89]) and favorable neurological outcome (AUC 0.84 [95% CI 0.80–0.88]). ConclusionIntegration of EPOS into clinical procedures may significantly improve clinical decision making and thus patient prognosis in the early time-crucial period after OHCA. However, further validation in other patient cohorts is needed.

Intercellular interaction between FAP+ fibroblasts and CD150+ inflammatory monocytes mediates fibrostenosis in Crohn's disease.

Crohn's disease (CD) is marked by recurring intestinal inflammation and tissue injury, often resulting in fibrostenosis and bowel obstruction, necessitating surgical intervention with high recurrence rates. To elucidate the mechanisms underlying fibrostenosis in CD, we analyzed the transcriptome of cells isolated from the transmural ileum of patients with CD, including a trio of lesions from each patient: non-affected, inflamed, and stenotic ileum samples, and compared them with samples from patients without CD. Our computational analysis revealed that profibrotic signals from a subset of monocyte-derived cells expressing CD150 induced a disease-specific fibroblast population, resulting in chronic inflammation and tissue fibrosis. The transcription factor TWIST1 was identified as a key modulator of fibroblast activation and extracellular matrix (ECM) deposition. Genetic and pharmacological inhibition of TWIST1 prevents fibroblast activation, reducing ECM production and collagen deposition. Our findings suggest that the myeloid-stromal axis may offer a promising therapeutic target to prevent fibrostenosis in CD.

Targeted therapy of glomerulonephritis via salvianolic acid b-loaded biomimetic hybrid nanovesicles driven by homing

BackgroundMesangial cell (MC)-mediated immune inflammatory injury is a basic pathological process in glomerulonephritis. However, due to the limited drug accumulation and serious adverse effects, it remains challenging to explore a rational delivery system integrating high efficiency and low toxicity to deliver anti-inflammatory drugs to the glomerular MC region. ResultsSalvianolic acid B (SAB)-loaded hybrid membrane biomimetic nanovesicles (SAB@HMVs) were developed by fusing erythrocyte membrane nanovesicles with mesenchymal stem cells biomimetic membrane nanovesicles. SAB@HMVs had a spheroidal structure, low cytotoxicity, particle size of 143.83 ± 1.33 nm and exhibited a high drug loading capacity (7.02 %±0.30 %) along with a good sustained release function. The in vitro anti-inflammatory results revealed that HMVs were effectively taken up by MCs and showed significant anti-inflammatory activity. Furthermore, in vivo pharmacodynamic studies revealed that SAB@HMVs could deliver SAB to kidney tissue and elicit an effective anti-inflammatory response to improve the pathological changes in the glomerular mesangial region, significantly reducing the levels of cytokines and alleviating kidney inflammation. Especially, noteworthy was the observation that SAB@HMVs augmented the renal delivery of SAB, downregulated the gene expression of p38 MAPK and NF-κB, inhibited the levels of MMP9 and TNF-α proteins as well as elevated the level of iκB protein, indicating that the anti-inflammatory mechanism of SAB@HMVs should be based on regulating MAPK and NF-κB signaling pathways. ConclusionWe provided a novel strategy to increase nanovesicles accumulation in MCs with the potential to exert anti-inflammatory regulatory effects in glomerulonephritis. Furthermore, this biomimetic hybrid membrane loaded with pure drugs may offer a functional platform to address multiple clinical needs.

Effect of Xanthohumol from Humulus lupulus L. Against Gouty Bone Damage in Arthritis of Rats Induced by Mono-sodium Urate.

Xanthohumol (XAN) is an isoprenyl flavonoid from Humulus lupulus L. known for beer brewing, and an osteoprotective agent due to its active improvement in bone loss of osteoporosis. This study was first time to investigate its effects on anti-gouty bone injury in rats of gouty arthritis (GA) induced by monosodium urate (MSU). Results showed that XAN could significantly exert anti-inflammatory activity by alleviating swelling degree of joints, reducing serum level of inflammatory factors, improving inflammatory injury and degrading the Markin's score in lesion joint. Meanwhile, XAN could also fight against gouty bone damage by improving pathological changes of bone tissue and parameters of bone micro-structure. Moreover, XAN could even promote bone formation by effectively enhancing expression of Runx2 and OPG, while inhibit bone resorption with depressing matrix metalloproteinase-9 (MMP-9), MMP-13 and CTSK expression, reducing RANKL secretion, and abating the ratio of RANKL/OPG. Therefore, it was the first time to reveal the mechanism of XAN against gouty bone injury via inhibiting RANKL/OPG/RANK signaling pathway. Above all, this study provided potential strategy for the treatment of GA, and further contributed to research and resource development for hops.

Kidney Injury in a Murine Hemorrhagic Shock/Resuscitation Model Is Alleviated by sulforaphane's Anti-Inflammatory and Antioxidant Action.

Hemorrhagic shock/resuscitation (HS/R) can lead to acute kidney injury, mainly manifested as oxidative stress and inflammatory injury in the renal tubular epithelial cells, as well as abnormal autophagy and apoptosis. Sulforaphane (SFN), an agonist of the nuclear factor-erythroid factor 2-related factor 2 (Nrf2) signaling pathway, is involved in multiple biological activities, such as anti-inflammatory, antioxidant, autophagy, and apoptosis regulation. This study investigated the effect of SFN on acute kidney injury after HS/R in mice. Hemorrhagic shock was induced in mice by controlling the arterial blood pressure at a range of 35-45mmHg for 90min within arterial blood withdrawal. Fluid resuscitation was carried out by reintroducing withdrawn blood and 0.9% NaCl. We found that SFN suppressed the elevation of urea nitrogen and serum creatinine levels in the blood induced by HS/R. SFN mitigated pathological alterations including swollen renal tubules and renal casts in kidney tissue of HS/R mice. Inflammation levels and oxidative stress were significantly downregulated in mouse kidney tissue after SFN administration. In addition, the kidney tissue of HS/R mice showed high levels of autophagosomes as observed by electron microscopy. However, SFN can further enhance the formation of autophagosomes in the HS/R + SFN group. SFN also increased autophagy-related proteins Beclin1 expression and suppressed P62 expression, while increasing the ratio of microtubule-associated protein 1 light chain 3 (LC3)-II and LC3-I (LC3-II/LC3-I). SFN also effectively decreased cleaved caspase-3 level and enhanced the ratio of anti-apoptotic protein B cell lymphoma 2 and Bcl2-associated X protein (Bcl2/Bax). Collectively, SFN effectively inhibited inflammation and oxidative stress, enhanced autophagy, thereby reducing HS/R-induced kidney injury and apoptosis levels in mouse kidneys.

Protective effects of CY-09 and astaxanthin on NaIO3-induced photoreceptor inflammation via the NLRP3/autophagy pathway.

To study the effect of the NLRP3/autophagy pathway on the photoreceptor inflammatory response and the protective mechanism of CY-09 and astaxanthin (AST). ICR mice were intraperitoneally injected NaIO3, CY-09, AST successively and divided into 5 groups, including the control, NaIO3, NaIO3+CY-09, NaIO3+AST, and NaIO3+CY-09+AST groups. Spectral domain optical coherence tomography and flash electroretinogram were examined and the retina tissues were harvested for immunohistochemistry, enzyme linked immunosorbent assay (ELISA), and Western blotting. Retinal pigment epithelium cell line (ARPE-19 cells) and mouse photoreceptor cells line (661W cells) were also treated with NaIO3, CY-09, and AST successively. Cell proliferation was assessed by cell counting kit-8 (CCK-8) assay. Apoptosis was analyzed by flow cytometry. Changes in autophagosome morphology were observed by transmission electron microscopy. Quantitative polymerase chain reaction (qPCR) was used to detect NLRP3 and caspase-1. NLRP3, caspase-1, cleaved caspase-1, p62, Beclin-1, and LC3 protein levels were measured by Western blotting. IL-1β and IL-18 were measured by ELISA. Compared with the control group, the activity of NaIO3-treated 661W cells decreased within 24 and 48h, apoptosis increased, NLRP3, caspase-1, IL-1β and IL-18 levels increased, and autophagy-related protein levels increased (P<0.05). Compared with NaIO3 group, CY-09 and AST inhibited apoptosis (P<0.05), reduced NLRP3, caspase-1, IL-1β and IL-18 expression (P<0.05), and inhibited autophagy. Compared with the other groups, CY-09 combined with AST significantly decreased NLRP3 expression and inhibited the expression of the autophagy-related proteins p62, Beclin-1, and LC3 in vitro and in vivo (P<0.05). CY-09 and AST inhibit NaIO3-induced inflammatory damage through the NLRP3/autophagy pathway in vitro and in vivo. CY-09 and AST may protect retina from inflammatory injury.

Hydrogel-Based Therapies for Ischemic and Hemorrhagic Stroke: A Comprehensive Review.

Stroke remains the second leading cause of death and a major cause of disability worldwide, significantly impacting individuals, families, and healthcare systems. This neurological emergency can be triggered by ischemic events, including small vessel arteriolosclerosis, cardioembolism, and large artery atherothromboembolism, as well as hemorrhagic incidents resulting from macrovascular lesions, venous sinus thrombosis, or vascular malformations, leading to significant neuronal damage. The resultant motor impairment, cognitive dysfunction, and emotional disturbances underscore the urgent need for effective therapeutic interventions. Recent advancements in biomaterials, particularly hydrogels, offer promising new avenues for stroke management. Hydrogels, composed of three-dimensional networks of hydrophilic polymers, are notable for their ability to absorb and retain substantial amounts of water. Commonly used polymers in hydrogel formulations include natural polymers like alginate, chitosan, and collagen, as well as synthetic polymers such as polyethylene glycol (PEG), polyvinyl alcohol (PVA), and polyacrylamide. Their customizable characteristics-such as their porosity, swelling behavior, mechanical strength, and degradation rates-make hydrogels ideal for biomedical applications, including drug delivery, cell delivery, tissue engineering, and the controlled release of therapeutic agents. This review comprehensively explores hydrogel-based approaches to both ischemic and hemorrhagic stroke therapy, elucidating the mechanisms by which hydrogels provide neuroprotection. It covers their application in drug delivery systems, their role in reducing inflammation and secondary injury, and their potential to support neurogenesis and angiogenesis. It also discusses current advancements in hydrogel technology and the significant challenges in translating these innovations from research into clinical practice. Additionally, it emphasizes the limited number of clinical trials utilizing hydrogel therapies for stroke and addresses the associated limitations and constraints, underscoring the need for further research in this field.

Multifunctional Glycopeptide-Based Hydrogel via Dual-Modulation for the Prevention and Repair of Radiation-Induced Skin Injury.

The radiation-induced skin injury (RISI) remains a great challenge for clinical wound management and care after radiotherapy, as patients will suffer from the acute radiation injury and long-term chronic inflammatory damage during the treatment. The excessive ROS in the early acute stage and prolonged inflammatory response in the late healing process always hinder therapeutic efficiency. Herein, we developed an extracellular matrix (ECM)-mimetic multifunctional glycopeptide hydrogel (oCP@As) to promote and accelerate RISI repair via a dual-modulation strategy in different healing stages. The oCP@As hydrogel not only can form an ECM-like nanofiber structure through the Schiff base reaction but also exhibits ROS scavenging and DNA double-strand break repair abilities, which can effectively reduce the acute radiation damage. Meanwhile, the introduction of oxidized chondroitin sulfate, which is the ECM polysaccharide-like component, enables regulation of the inflammatory response by adsorption of inflammatory factors, accelerating the repair of chronic inflammatory injury. The animal experiments demonstrated that oCP@As can significantly weaken RISI symptoms, promote epidermal tissue regeneration and angiogenesis, and reduce pro-inflammatory cytokine expression. Therefore, this multifunctional glycopeptide hydrogel dressing can effectively attenuate RISI symptoms and promote RISI healing, showing great potential for clinical applications in radiotherapy protection and repair.

Renalase peptides reduce pancreatitis severity in mice.

Acute pancreatitis, an acute inflammatory injury of the pancreas, lacks a specific treatment. The circulatory protein renalase is produced by the kidney and other tissues and has potent anti-inflammatory and prosurvival properties. Recombinant renalase can reduce the severity of mild cerulein pancreatitis; the activity is contained in a conserved 20 aa renalase site (RP220). Here, we investigated the therapeutic effects of renalase on pancreatitis using two clinically relevant models of acute pancreatitis. The ability of peptides containing the RP220 site to reduce injury in a 1-day post-endoscopic retrograde cholangiopancreatography (ERCP) and a 2-day severe cerulein induced in mice was examined. The initial dose of renalase peptides was given either prophylactically (before) or therapeutically (after) the initiation of the disease. Samples were collected to determine early pancreatitis responses (tissue edema, plasma amylase, active zymogens) and later histologic tissue injury and inflammatory changes. In both preclinical models, renalase peptides significantly reduced histologic damage associated with pancreatitis, especially inflammation, necrosis, and overall injury. Quantifying inflammation using specific immunohistochemical markers demonstrated that renalase peptides significantly reduced overall bone marrow-derived inflammation and neutrophils and macrophage populations in both models. In the severe cerulein model, administering a renalase peptide with or without pretreatment significantly reduced injury. Pancreatitis and renalase peptide effects appeared to be the same in female and male mice. These studies suggest renalase peptides that retain the anti-inflammatory and prosurvival properties of recombinant renalase can reduce the severity of acute pancreatitis and might be attractive candidates for therapeutic development.NEW & NOTEWORTHY Renalase is a secretory protein. The prosurvival and anti-inflammatory effects of the whole molecule are contained in a 20 aa renalase site (RP220). Systemic treatment with peptides containing this renalase site reduced the severity of post-endoscopic retrograde cholangiopancreatography (ERCP) and severe cerulein pancreatitis in mouse models.

Prospective randomized controlled trial on the safety and neuroprotective efficacy of remote administration of hypothermia over spleen during acute ischemic stroke with mechanical thrombectomy: rationale, design, and protocol.

Brain inflammation plays a key role in ischemia/reperfusion (I/R) injury and is the main cause of "ineffective or futile recanalization" after successful mechanical thrombectomy (MT) in acute ischemic stroke (AIS). One of the primary sources of inflammatory cells after AIS are derived from the spleen. As an innovative and potential neuroprotective strategy after stroke, Remote Administration of Hypothermia (RAH) temporarily suppresses immune activities in the spleen, reduces the release of inflammatory cells and cytokines into blood, and thus reversibly diminishes inflammatory injury in the brain. This single-center, prospective, randomized controlled study (RCT) is proposed for AIS patients with anterior circulation large vessel occlusion (LVO). Subjects will be randomly assigned to either the control or intervention groups in a 1:1 ratio (n = 40). Participants allocated to the intervention group will receive RAH on the abdomen above the spleen prior to recanalization until 6 h after thrombectomy. All enrolled patients will receive standard stroke Guideline care. The main adverse events associated with RAH are focal cold intolerance and abdominal pain. The primary outcome will assess safety as it pertains to RAH application. The secondary outcomes include the efficacy of RAH on spleen, determined by spleen volumes, blood inflammatory factor (cells and cytokines), and on brain injury, determined by infarction volumes and poststroke functional outcomes. This study aims to examine the safety and preliminary effectiveness of RAH over the spleen during endovascular therapy in AIS patients. The results of this study are expected to facilitate larger randomized clinical trials and hopefully prove RAH administration confers adjuvant neuroprotective properties in AIS treated with MT. https://www.chictr.org.cn/. Identifier ChiCTR 2300077052.

Sodium selenite attenuates inflammatory response and oxidative stress injury by regulating the Nrf2/ARE pathway in contrast-induced acute kidney injury in rats

BackgroundContrast-induced acute kidney injury (CI-AKI) is an acute renal complication that occurs after intravascular contrast agent administration. Sodium selenite (SS) is an inorganic source of Se and has potent antioxidant properties. This study intends to examine its anti-inflammatory and antioxidant effects in CI-AKI.MethodsA rat CI-AKI model was established with the pretreatment of SS (0.35 mg/kg). Hematoxylin-eosin staining was employed for histopathological analysis of rat kidney specimens. Biochemical analysis was conducted for renal function detection. Tissue levels of oxidative stress-related markers were estimated. Reverse transcription-quantitative polymerase chain reaction revealed the mRNA levels of proinflammatory cytokines. Western blotting showed the Nrf2 signaling-related protein expression in the rat kidney.ResultsSS administration alleviated the renal pathological changes and reduced the serum levels of serum creatinine, blood urea nitrogen, neutrophil gelatinase-associated lipocalin, cystatin C, and urinary level of kidney injury molecule-1 in CI-AKI rats. SS attenuated oxidative stress and inflammatory response in CI-AKI rat kidney tissues. SS activated the Nrf2 signaling transduction in the renal tissues of rats with CI-AKI.ConclusionSS ameliorates CI-AKI in rats by reducing oxidative stress and inflammation via the Nrf2 signaling.

Differential immunometabolic responses to Delta and Omicron SARS-CoV-2 variants in golden syrian hamsters

Delta (B.1.617.2) and Omicron (B.1.1.529) variants of SARS-CoV-2 represents unique clinical characteristics. However, their role in altering immunometabolic regulations during acute infection remains convoluted. Here, we evaluated the differential immunopathogenesis of Delta vs. Omicron variants in Golden Syrian hamsters (GSH). The Delta variant resulted in higher virus titers in throat swabs and the lungs and exhibited higher lung damage with immune cell infiltration than the Omicron variant. The gene expression levels of immune mediators and metabolic enzymes, Arg-1 and IDO1 in the Delta-infected lungs were significantly higher compared to Omicron. Further, Delta/Omicron infection perturbed carbohydrates, amino acids, nucleotides, and TCA cycle metabolites and was differentially regulated compared to uninfected lungs. Collectively, our data provide a novel insight into immunometabolic/pathogenic outcomes for Delta vs. Omicron infection in the GSH displaying concordance with COVID-19 patients associated with inflammation and tissue injury during acute infection that offered possible new targets to develop potential therapeutics.

Characterization of Eurotium cristatum Fermented Thinned Young Apple and Mechanisms Underlying Its Alleviating Impacts on Experimental Colitis.

A hundred million tons of young apples are thinned and discarded in the orchard per year, aiming to increase the yield and quality of apples. We fermented thinned young apples using a potential probiotic fungus, Eurotium cristatum, which notably disrupted the microstructure of raw samples, as characterized by the scanning electron microscope. Fermentation substantially altered the metabolite profiles of samples, which are predicted to alleviate colitis via regulating inflammatory response and response to lipopolysaccharide by using network pharmacology analysis. In vivo, oral gavage of water extracts of E. cristatum fermented young apples (E.YAP) effectively alleviated DSS-induced colitis, restored the histopathology damage, reduced the levels of inflammatory cytokines, and promoted colonic expressions of tight junction proteins. Moreover, E.YAP ameliorated gut dysbacteriosis by increasing abundances of Lactobacillus,Blautia, Muribaculaceae, and Prevotellaceae_UCG-001 while inhibiting Turicibacter, Alistipes, and Desulfovibrio. Importantly, E.YAP increased colonic bile acids, such as CA, TCA, DCA, TUDCA, and LCA, thereby alleviating colitis via PXR/NF-κB signaling. Furthermore, a synbiotic combination with Limosilactobacillus reuteri WX-94, a probiotic strain isolated from feces of healthy individuals with anti-inflammatory properties, augmented anticolitis capacities of E.YAP. Our findings demonstrate that E.YAP could be a novel, potent, food-based anti-inflammatory prebiotic for relieving inflammatory injuries.

Repression of BRD4 mitigates NLRP3 inflammasome-mediated pyroptosis in Mycobacterium-infected macrophages by repressing endoplasmic reticulum stress

Tuberculosis (TB) is the leading cause of human death worldwide due to Mycobacterium tuberculosis (Mtb) infection. Multiple lines of evidences have illuminated the emerging role of NLRP3 inflammasome-mediated pyroptosis in the clearance of pathogenic infection. In the current study, we sought to investigate the functional role and feasible potential mechanism of BRD4 in Mtb-infected macrophages. We observed that BRD4 was distinctly ascended in THP-1 macrophages upon Mtb infection. Functionally, intervention of BRD4 or pretreated with JQ1 obviously restricted Mtb-triggered cell pyroptosis, as evidenced by declination of protein level of the specific pyroptosis markers including Cleaved Caspase 1, gasdermin D (GSDMD-N) and Cleaved-IL-1β. In the meanwhile, disruption of BRD4 or JQ1 application remarkably prohibited excessive inflammatory responses as characterized by reduce the production of the inflammatory factors such as IL-1β and IL-18. Concomitantly, disruption of BRD4 or administrated with JQ1 manifestly repressed Mtb-aroused Nod-like receptor family pyrindomain-containing 3 (NLRP3) inflammasome activation, as witnessed by attenuation of protein levels of NLRP3, Pro-Caspase1 and apoptosis-associated speck-like protein (ASC). The above findings clearly demonstrated that suppression of BRD4 exerted great influence on regulating Mtb-elicited inflammatory response by coordinating NLRP3 inflammasome-mediated pyroptosis. More importantly, perturbation of BRD4 or JQ1 employment notably restrained endoplasmic reticulum (ER) stress triggered by Mtb-infection, as reflected by noticeably lessened the levels of GRP78, CHOP and ATF6. In terms of mechanism, ER stress agonist tunicamycin profoundly abrogated the favorable effects of BRD4 inhibition on Mtb-triggered pyroptosis, inflammation reaction and inflammasome activation. Collectively, these preceding outcomes strongly illuminated that inhibition of BRD4 targeted ER stress to retard NLRP3 inflammasome activation and subsequent cell pyroptosis and prevention of inflammatory response in Mtb-infected macrophages, highlighting that blocking BRD4 might serve as a promising candidate for protection against Mtb-triggered inflammatory injury.

Quercetin inhibits hypertonicity-induced inflammatory injury in human corneal epithelial cells via the PTEN/PI3K/AKT pathway

Dry eye is a prevalent ophthalmic disease. Ocular surface inflammation in the hyperosmolar environment of the tear film is critical in dry eye progression. Quercetin has strong anti-inflammatory effects; however, its exact mechanism of action in dry eye is not fully understood. Therefore, this study investigated whether quercetin could inhibit the damage sustained to human corneal epithelial cells (HCECs) in a hyperosmolar environment through its anti-inflammatory effects. HCECs were cultured in a complete medium and were divided into four groups: normal, model, quercetin, and inhibitor. The proliferation of HCECs was detected by Ki67 staining; the expression levels of PTEN, p-PI3K and p-AKT were detected by Western blotting and immunofluorescence staining; the relative mRNA expression levels of PTEN, PI3K, AKT, IL-6 and TNF-ɑ were detected by quantitative real-time PCR; the relative expression levels of IL-6 and TNF-α were detected by enzyme-linked immunosorbent assay. In this study, the proliferation of HCECs in the model group was found to be significantly inhibited compared with that in the normal group; however, quercetin was effective in improving the proliferation of HCECs, decreasing the relative expression of p-PI3K, p-AKT, IL-6, TNF-ɑ as well as increasing PTEN. In conclusion, this study demonstrated that quercetin could promote the proliferation of HCECs and reduce the expression of inflammatory factors by inhibiting the PTEN/PI3K/AKT pathway in the hyperosmolarity-induced HCECs model.

Anti-IL-17 Inhibits PINK1/Parkin Autophagy and M1 Macrophage Polarization in Rheumatic Heart Disease.

Rheumatic heart disease (RHD) is an important and preventable cause of cardiovascular death and disability, but the lack of clarity about its exact mechanisms makes it more difficult to find alternative methods or prevention and treatment. We previously demonstrated that increased IL-17 expression plays a crucial role in the development of RHD-related valvular inflammatory injury. Macrophage autophagy/polarization may be a pro-survival strategy in the initiation and resolution of the inflammatory process. This study investigated the mechanism by which IL-17 regulates autophagy/polarization activation in macrophages. A RHD rat model was generated, and the effects of anti-IL-17 and 3-methyladenine (3-MA) were analyzed. The molecular mechanisms underlying IL-17-induced macrophage autophagy/polarization were investigated via in vitro experiments. In our established RHD rat model, the activation of the macrophage PINK1/Parkin autophagic pathway in valve tissue was accompanied by M1 macrophage infiltration, and anti-IL-17 treatment inhibited autophagy and reversed macrophage inflammatory infiltration, thereby attenuating endothelial-mesenchymal transition (EndMT) in the valve tissue. The efficacy of 3-MA treatment was similar to that of anti-IL-17 treatment. Furthermore, in THP-1 cells, the pharmacological promotion of autophagy by IL-17 induced M1-type polarization, whereas the inhibition of autophagy by 3-MA reversed this process. Mechanistically, silencing PINK1 in THP-1 blocked autophagic flux. Moreover, IL-17-induced M1-polarized macrophages promoted EndMT in HUVECs. This study revealed that IL-17 plays an important role in EndMT in RHD via the PINK1/Parkin autophagic pathway and macrophage polarization, providing a potential therapeutic target.

Sestrin2 Restricts Endothelial-to-Mesenchymal Transition Induced by Lipolysaccharide via Autophagy.

Endothelial-to-mesenchymal transition (EndoMT) is a significant biological phenomenon wherein endothelial cells undergo a loss of their endothelial traits and progressively acquire mesenchymal characteristics. Consequently, this transformation leads to both a compromised ability to maintain lumen permeability and alterations in vascular structure, which hampers the preservation of blood-brain barrier integrity. This study aimed to investigate inflammation-induced EndoMT and its etiology, with the goal of impeding the infiltration of peripheral inflammation into the central nervous system. Lipolysaccharide (LPS) was administered intraperitoneally to mice several times to establish a chronic inflammatory model. A cellular inflammatory model was established by LPS in human brain microvascular endothelial cells (HBMECs). The mRNA expressions of inflammatory cytokines interleukin-1β (IL-1β) and IL-6 were detected by real-time polymerase chain reaction (PCR). Immunofluorescence staining of platelet endothelial cell adhesion molecule-1 (CD31) and alpha smooth muscle actin (α-SMA) was conducted to assess the level of EndoMT. The expression levels of Occludin, zona occludens protein 1 (ZO-1), Sestrin2, microtubule-associated protein1 light chain 3 (LC3) and inducible nitric oxide synthase (iNOS) were detected by western blotting. LPS treatment induced the downregulation of ZO-1 and Occludin, which was accompanied by the elevated expressions of iNOS, α-SMA, Sestrin2 and LC3-II in the mouse cortex and HBMECs. Mechanistically, the knockdown of Sestrin2 in HBMECs exacerbated the EndoMT induced by LPS treatment, while the overexpression of Sestrin2 inhibited this process. Moreover, the induction of autophagy by rapamycin rescued the EndoMT induced by Sestrin2 knockdown. This study revealed that Sestrin2 inhibited endothelial inflammation and EndoMT via enhanced autophagy, which may provide a potential drug target for cerebrovascular inflammatory injury.

The processed Euphorbia lathyris L. alleviates the inflammatory injury via regulating LXRα/ABCA1 expression and TLR4 positioning to lipid rafts

Euphorbia lathyris L. (EL) is a traditional poisonous herbal medicine used to treat dropsy, ascites, amenorrhea, anuria and constipation. Processing to reduce toxicity of EL is essential for its safe and effective application. However, there is little known regarding the molecular mechanism of reducing toxicity after EL processing. This research aimed to screen the differential markers for EL and PEL, explore the differential mechanisms of inflammatory injury induced by EL and processed EL (PEL) to expound the mechanism of alleviating toxicity after EL processing. The results showed that 15 potential biomarkers, mainly belonging to diterpenoids, were screened to distinguish EL from PEL. EL promoted the expressions of TLR4, NLRP3, NF-κB p65, IL-1β and TNF-α, increased lipid rafts abundance and promoted TLR4 positioning to lipid rafts. Meanwhile, EL decreased LXRα and ABCA1 expression, and reduced cholesterol efflux. In contrast to EL, the effects of PEL on these indicators were markedly weakened. In addition, Euphorbia factors L1, L2, and L3 affected LXRα, ABCA1, TLR4, NLRP3, NF-κB p65, TNF-α and IL-1β expression, influenced cholesterol efflux and lipid rafts abundance, and interfered with the colocalization of TLR4 and lipid rafts. The inflammatory injury caused by processed EL was significantly weaker than that caused by crude EL, and reduction of Euphorbia factors L1, L2, and L3 as well as attenuation of inflammatory injury participated in processing-based detoxification of EL. Our results provide valuable insights into the attenuated mechanism of EL processing and will guide future research on the processing mechanism of toxic traditional Chinese medicine.

RNF31-mediated IKKα ubiquitination aggravates inflammation and intestinal injury through regulating NF-κB activation in human and mouse neonates

AimsNeonatal necrotizing enterocolitis (NEC) is a leading cause of intestine inflammatory disease, and macrophage is significantly activated during NEC development. Posttranslational modifications (PTMs) of proteins, particularly ubiquitination, play critical roles in immune response. This study aimed to investigate the effects of ubiquitin-modified proteins on macrophage activation and NEC, and discover novel NEC-related inflammatory proteins. Materials and methodsProteomic and ubiquitin proteomic analyses of intestinal macrophages in NEC/healthy mouse pups were carried out. In vitro macrophage inflammation model and in vivo NEC mouse model, as well as clinical human samples were used for further verification the inhibitor of nuclear factor-κB kinase α (IKKα) ubiquitination on NEC development through Western blot, immunofluorescence, quantitative real-time polymerase chain reaction (qRT-PCR) and flow cytometry. Key findingsWe report here that IKKα was a new ubiquitin-modified protein during NEC through ubiquitin proteomics, and RING finger protein 31 (RNF31) acted as an E3 ligase to be involved in IKKα degradation. Inhibition of IKKα ubiquitination and degradation with siRNF31 or proteasome inhibitor decreased nuclear factor-κB (NF-κB) activation, thereby decreasing the expression of pro-inflammatory factors and M1 macrophage polarization, resulting in reliving the severity of NEC. SignificanceOur study suggests the activation of RNF31-IKKα-NF-κB axis triggering NEC development and suppressing RNF31-mediated IKKα degradation may be therapeutic strategies to be developed for NEC treatment.