Expression Of Inflammatory Mediators Research Articles

Betulin protects against isoproterenol-induced myocardial injury by inhibiting NF-κB signaling and attenuating cardiac inflammation and oxidative stress in rats

Objective: To investigate the cardioprotective potential of betulin in isoproterenol (ISO)-induced myocardial injury in rats. Methods: Wistar rats were divided into five groups (n=10): normal, ISO, nebivolol 5 mg/kg, and betulin (20 & 40 mg/kg). Nebivolol and betulin were administered orally for 29 days. ISO (85 mg/kg) was administered subcutaneously on day 27 and day 28 to induce myocardial injury. On day 29, blood was collected for determination of cardiac markers, and hemodynamic parameters were investigated. The levels of oxidative stress markers and the gene expressions of apoptotic markers and inflammatory mediators were evaluated. Moreover, 2,3,5-triphenyltetrazolium chloride staining and histopathological analysis were also performed. Results: Betulin reduced the size of myocardial infarction, decreased elevated levels of cardiac enzymes, and maintained hemodynamic functions. It also inhibited ISO-induced upregulation of Bax, caspase-3, NF-κB, and 1L-6, enhanced endogenous antioxidant enzymes, and reduced lipid peroxidation. Additionally, pretreatment with betulin alleviated myocardial ischemic damage, as reflected by reduced myonecrosis, edema, and inflammatory changes. Conclusions: Betulin exhibits strong cardioprotective activity against ISO-induced myocardial injury by anti-inflammatory, anti-apoptotic, and antioxidant activities.

Resolving neutrophils through genetic deletion of TRAM attenuate atherosclerosis pathogenesis

Systemic neutrophil dysregulation contributes to atherosclerosis pathogenesis, and restoring neutrophil homeostasis may be beneficial for treating atherosclerosis. Herein, we report that a homeostatic resolving subset of neutrophils exists in mice and humans characterized by the low expression of TRAM, correlated with reduced expression of inflammatory mediators (leukotriene B4 [LTB4] and elastase) and elevated expression of anti-inflammatory resolving mediators (resolvin D1 [RvD1] and CD200R). TRAM-deficient neutrophils can potently improve vascular integrity and suppress atherosclerosis pathogenesis when adoptively transfused into recipient atherosclerotic animals. Mechanistically, we show that TRAM deficiency correlates with reduced expression of 5-lipoxygenase (LOX5) activating protein (LOX5AP), dislodges nuclear localization of LOX5, and switches the lipid mediator secretion from pro-inflammatory LTB4 to pro-resolving RvD1. TRAM also serves as a stress sensor of oxidized low-density lipoprotein (oxLDL) and/or free cholesterol and triggers inflammatory signaling processes that facilitate elastase release. Together, our study defines a unique neutrophil population characterized by reduced TRAM, capable of homeostatic resolution and treatment of atherosclerosis.

Ebselen improves fungal keratitis through exerting anti-inflammation, anti-oxidative stress, and antifungal effects

Fungal keratitis is a severely vision-threatening corneal infection, where the prognosis depends on both fungal virulence and host immune defense. Inappropriate host responses can induce substantial inflammatory damage to the cornea. Therefore, in the treatment of fungal keratitis, it is important to concurrently regulate the immune response while efforts are made to eliminate the pathogen. Ebselen is a widely studied organo-selenium compound and has been demonstrated to have antifungal, antibacterial, anti-inflammatory, and oxidative stress-regulatory properties. The effectiveness of ebselen for the treatment of fungal keratitis remains unknown. In this study, ebselen was demonstrated to produce a marked inhibitory effect on Aspergillus fumigatus (A. fumigatus), including spore germination inhibition, mycelial growth reduction, and fungal biofilm disruption. The antifungal activity of ebselen was related to the cell membrane damage caused by thioredoxin (Trx) system inhibition-mediated oxidative stress. On the contrary, ebselen enhanced the antioxidation of Trx system in mammalian cells. Further, ebselen was proven to suppress the expressions of inflammatory mediators (IL-1β, IL-6, TNF-α, COX-2, iNOS, and CCL2) and reduce the production of oxidative stress-associated indicators (ROS, NO, and MDA) in fungi-stimulated RAW264.7 cells. In addition, ebselen regulated PI3K/Akt/Nrf2 and p38 MAPK signaling pathways, which contributed to the improvement of inflammation and oxidative stress. Finally, we verified the therapeutic effect of ebselen on mouse fungal keratitis. Ebselen improved the prognosis and reduced the fungal burden in mouse corneas. Expressions of inflammatory mediators, as well as the infiltration of macrophages and neutrophils in the cornea were also obviously decreased by ebselen. In summary, ebselen exerted therapeutic effects by reducing fungal load and protecting host tissues in fungal keratitis, making it a promising treatment for fungal infections.

Emodin nanocapsules inhibit acute pancreatitis by regulating lipid metabolic reprogramming in macrophage polarization

BackgroundEmodin is a chemical compound found in traditional Chinese herbs. It possesses anti-inflammatory and many other pharmacological effects. Our previous study showed that emodin significantly alleviates the inflammation effect of severe acute pancreatitis (SAP). However, its poor solubility, high toxicity and limited pancreas retention time hinder its clinical application. PurposeWe aimed to prepare emodin nanocapsules with improved bioavailability to achieve the controlled release of emodin by targeting macrophages. Further, the mechanism of mannose-conjugated chitosan-coated lipid nanocapsules loaded with emodin (M-CS-E-LNC) in the treatment of SAP was explored. MethodsM-CS-E-LNC were prepared by the phase inversion method with slight modification. The expression of inflammation mediators and the anti-inflammation efficacy of M-CS-E-LNC were examined by ELISA, IHC and IF in macrophage cells and LPS-induced SAP mice. IVIS spectrum imaging and HPLC were applied to explore the controlled release of M-CS-E-LNC in the pancreas. LC-MS/MS was performed for lipidomics analysis of macrophages. Moreover, a vector-based short hairpin RNA (shRNA) method was used to silence CTP1 gene expression in macrophage cells. ResultsThe levels of inflammatory mediators in macrophages were markedly decreased after treatment with M-CS-E-LNC. The same anti-inflammation effects were detected in SAP mouse through the analysis of serum levels of amylase, TNF-α and IL-6. Importantly, M-CS-E-LNC allowed the emodin to selectively accumulate at pancreas and gastrointestinal tissues, thus exhibiting a targeted release. Mechanistically, the M-CS-E-LNC treatment group showed up-regulated expression of the carnitine palmitoyltransferase 1 (CPT1) protein which promoted intracellular long-chain fatty acid transport, thereby promoting the M2 phenotype polarization of macrophages. ConclusionM-CS-E-LNC exhibited significantly improved bioavailability and water solubility, which translated to greater therapeutic effects on macrophage polarization. Our findings also demonstrate, for the first time, that CPT1 may be a new therapeutic target for SAP treatment.

Acacetin Attenuates Sepsis-induced Acute Lung Injury via NLRC3-NF-κB Pathway.

Acacetin, a flavonoid derived compound has been recognized for its diverse biological activities, such as anti-oxidative and anti-inflammatory effects. Acute lung injury (ALI) is a severe condition characterized by respiratory insufficiency and tissue damage, commonly triggered by pneumonia and severe sepsis. These conditions induce an inflammatory response via Toll-like receptor 4 (TLR4) signaling activation. This study explored acacetin's therapeutic potential against lipopolysaccharide (LPS) induced ALI in mice, focusing on its ability to modulate the NF-κB pathway via regulation of the Nod-like receptor family CARD domain containing 3 (NLRC3), a signal sensor that plays an important role in the regulation of inflammation and the maintenance of homeostasis. Our findings revealed that high-dose acacetin reduced the mortality rate of ALI mice, significantly ameliorated LPS-induced lung pathological changes, reduced lung edema, and decreased the expression of inflammatory mediators in lung tissues. This protective impact of acacetin appears to stem form its capacity to enhance NLRC3 expression, which, intern, can inhibit the activation of NF-κB and subsequently inhibit the production of inflammatory mediators. NLRC3 deficiency inhibits the protective effect of acacetin on ALI mice. Molecular docking also verified that acacetin tightly bound acacetin to NLRC3. Additionally, acacetin was found to influence macrophage recruitment dynamics via NLRC3, inhibiting the overactivation of NLRC3-NF-κB related pathways. Taken together, our results indicate that acacetin inhibited LPS-induced acute lung injury and macrophage overrecruitment to the lungs in mice by upregulating NLRC3.

The atypical chemokine receptor 2 reduces T cell expansion and tertiary lymphoid tissue but does not limit autoimmune organ injury in lupus-prone B6lpr mice.

The atypical chemokine receptor 2 (ACKR2) is a chemokine scavenger receptor, which limits inflammation and organ damage in several experimental disease models including kidney diseases. However, potential roles of ACKR2 in reducing inflammation and tissue injury in autoimmune disorders like systemic lupus erythematosus (SLE) and lupus nephritis are unknown, as well as its effects on systemic autoimmunity. To characterize functional roles of ACKR2 in SLE, genetic Ackr2 deficiency was introduced into lupus-prone C57BL/6lpr (Ackr2-/- B6lpr) mice. Upon inflammatory stimulation in vitro, secreted chemokine levels increased in Ackr2 deficient tubulointerstitial tissue but not glomeruli. Moreover, Ackr2 expression was induced in kidneys and lungs of female C57BL/6lpr mice developing SLE. However, female Ackr2-/- B6lpr mice at 28 weeks of age showed similar renal functional parameters as wildtype (WT)-B6lpr mice. Consistently, assessment of activity and chronicity indices for lupus nephritis revealed comparable renal injury. Interestingly, Ackr2-/- B6lpr mice showed significantly increased renal infiltrates of CD3+ T and B cells, but not neutrophils, macrophages or dendritic cells, with T cells predominantly accumulating in the tubulointerstitial compartment of Ackr2-/- B6lpr mice. In addition, histology demonstrated significantly increased peribronchial lung infiltrates of CD3+ T cells in Ackr2-/- B6lpr mice. Despite this, protein levels of pro-inflammatory chemokines and mRNA expression of inflammatory mediators were not different in kidneys and lungs of WT- and Ackr2-/- B6lpr mice. This data suggests compensatory mechanisms for sufficient chemokine clearance in Ackr2-deficient B6lpr mice in vivo. Analysis of systemic autoimmune responses revealed comparable levels of circulating lupus-associated autoantibodies and glomerular immunoglobulin deposition in the two genotypes. Interestingly, similar to kidney and lung CD4+ T cell numbers and activation were significantly increased in spleens of Ackr2-deficient B6lpr mice. In lymph nodes of Ackr2-/- B6lpr mice abundance of activated dendritic cells decreased, but CD4+ T cell numbers were comparable to WT. Moreover, increased plasma levels of CCL2 were present in Ackr2-/- B6lpr mice, which may facilitate T cell mobilization into spleens and peripheral organs. In summary, we show that ACKR2 prevents expansion of T cells and formation of tertiary lymphoid tissue, but is not essential to limit autoimmune tissue injury in lupus-prone B6lpr mice.

Aflatoxin B1 exposure deteriorates immune abnormalities in a BTBR T+ Itpr3tf/J mouse model of autism by increasing inflammatory mediators' production in CD19-expressing cells

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by deficiencies in communication, repetitive and stereotyped behavioral patterns, and difficulties in reciprocal social engagement. The presence of immunological dysfunction in ASD has been well established. Aflatoxin B1 (AFB1) is a prevalent mycotoxin found in food and feed, causing immune toxicity and hepatotoxicity. AFB1 is significantly elevated in several regions around the globe. Existing research indicates that prolonged exposure to AFB1 results in neurological problems. The BTBR T+ Itpr3tf/J (BTBR) mice, which were used as an autism model, exhibit the primary behavioral traits that define ASD, such as repeated, stereotyped behaviors and impaired social interactions. The main objective of this work was to assess the toxic impact of AFB1 in BTBR mice. This work aimed to examine the effects of AFB1 on the expression of Notch-1, IL-6, MCP-1, iNOS, GM-CSF, and NF-κB p65 by CD19+ B cells in the spleen of the BTBR using flow cytometry. We also verified the impact of AFB1 exposure on the mRNA expression levels of Notch-1, IL-6, MCP-1, iNOS, GM-CSF, and NF-κB p65 in the brain of BTBR mice using real-time PCR. The findings of our study showed that the mice treated with AFB1 in the BTBR group exhibited a substantial increase in the presence of CD19+Notch-1+, CD19+IL-6+, CD19+MCP-1+, CD19+iNOS+, CD19+GM-CSF+, and CD19+NF-κB p65+ compared to the mice in the BTBR group that were treated with saline. Our findings also confirmed that administering AFB1 to BTBR mice leads to elevated mRNA expression levels of Notch-1, IL-6, MCP-1, iNOS, GM-CSF, and NF-κB p65 in the brain, in comparison to BTBR mice treated with saline. The data highlight that exposure to AFB1 worsens immunological abnormalities by increasing the expression of inflammatory mediators in BTBR mice.

Exploring Salivary Epithelial Dysfunction in Sjögren's Disease.

Sjögren's Disease (SjD) is an autoimmune disease of the exocrine tissues. Etiological events result in the loss of epithelial homeostasis alongside extracellular matrix (ECM) destruction within the salivary and lacrimal glands, followed by immune cell infiltration. In this review, we have assessed the current understanding of epithelial-mesenchymal transition (EMT)-associated changes within the salivary epithelium potentially involved in salivary dysfunction and SjD pathogenesis. We performed a PubMed literature review pertaining to the determination of pathogenic events that lead to EMT-related epithelial dysfunction and signaling in SjD. Molecular patterns of epithelial dysfunction in SjD salivary glands share commonalities with EMT mediating wound healing. Pathological changes altering salivary gland integrity and function may precede direct immune involvement while perpetuating MMP9-mediated ECM destruction, inflammatory mediator expression, and eventual immune cell infiltration. Dysregulation of EMT-associated factors is present in the salivary epithelium of SjD and may be significant in initiating and perpetuating the disease. In this review, we further highlight the gap regarding mechanisms that drive epithelial dysfunction in salivary glands in the early or subclinical pre-lymphocytic infiltration stages of SjD.

Coarse particulate matter (PM10) induce an inflammatory response through the NLRP3 activation

IntroductionPM exposure can induce inflammatory and oxidative responses; however, differences in these adverse effects have been reported depending on the chemical composition and size. Moreover, inflammatory mechanisms such as NLRP3 activation by PM10 have yet to be explored.ObjectiveTo assess the impact of PM10 on cell cytotoxicity and the inflammatory response through in vitro and in vivo models.MethodologyPeripheral blood mononuclear cells (PBMCs) from healthy donors were exposed to PM10. Cytotoxicity was determined using the LDH assay; the expression of inflammasome components and the production of pro-inflammatory cytokines were quantified through qPCR and ELISA, respectively; and the formation of ASC complexes was examined using confocal microscopy. For in vivo analysis, male C57BL6 mice were intranasally challenged with PM10 and bronchoalveolar lavage fluid was collected to determine cell counts and quantification of pro-inflammatory cytokines by ELISA. RNA was extracted from lung tissue, and the gene expression of inflammatory mediators was quantified.ResultsPM10 exposure induced significant cytotoxicity at concentrations over 100 µg/mL. Moreover, PM10 enhances the gene expression and release of pro-inflammatory cytokines in PBMCs, particularly IL-1β; and induces the formation of ASC complexes in a dose-dependent manner. In vivo, PM10 exposure led to cell recruitment to the lungs, which was characterized by a significant increase in polymorphonuclear cells compared to control animals. Furthermore, PM10 induces the expression of several inflammatory response-related genes, such as NLRP3, IL-1β and IL-18, within lung tissue.ConclusionBriefly, PM10 exposure reduced the viability of primary cells and triggered an inflammatory response, involving NLRP3 inflammasome activation and the subsequent production of IL-1β. Moreover, PM10 induces the recruitment of cells to the lung and the expression of multiple cytokines; this phenomenon could contribute to epithelial damage and, thus to the development and exacerbation of respiratory diseases such as viral infections.

YTHDF1 shapes immune-mediated hepatitis via regulating inflammatory cell recruitment and response

Severe immune responses regulate the various clinical hepatic injuries, including autoimmune hepatitis and acute viral hepatitis. N6-methyladenosine (m6A) modification is a crucial regulator of immunity and inflammation. However, the precise role of YTHDF1 in T cell-mediated hepatitis remains incompletely characterized. To address this, we utilized Concanavalin A (ConA)-induced mouse liver damage as an experimental model for T cell-mediated hepatitis. Our findings found that hepatic YTHDF1 protein rapidly decreased during ConA-induced hepatitis, and YTHDF1-deficient (Ythdf1−/−) mice showed more susceptibility to ConA-induced liver injury, along with an intensified inflammatory storm accompanied by aggravated hepatic inflammatory response via ERK and NF-κB pathways. Interestingly, hepatic-specific over-expression or deletion of YTHDF1 exhibited redundancy in ConA-induced liver injury. Validation in bone marrow chimeric mice confirmed the necessity of YTHDF1 in hematopoietic cells for controlling the response to ConA-induced hepatitis. Additionally, our data revealed that YTHDF1 deletion in macrophages exacerbated the inflammatory response induced by lipopolysaccharide. In summary, our study uncovered that YTHDF1 deficiency exacerbates the immune response in ConA-induced hepatitis by modulating the expression of inflammatory mediators, highlighting the potential of YTHDF1 as a therapeutic target for clinical hepatitis.

Abstract 2082: Neutrophil Programming In Atherosclerosis

Emerging evidence suggest the involvement of neutrophils during the progression of human atherosclerosis through secreting inflammatory mediators and causing damages to endothelial vasculature. However, compared to other well-recognized immune cells such as monocytes/macrophages, mechanisms underlying the regulation of neutrophils during atherosclerosis are relatively less studied and understood. This presents a major impediment in our thorough understanding of the pathogenesis of atherosclerosis. In this study, we reported that both murine and human neutrophil population possesses a minor homeostatic resolving subset characterized by reduced expression of inflammatory mediators (LTB4, elastase), elevated expression of anti-inflammatory resolving mediators (RvD1, CD200R), correlated with reduced expression of inflammatory signaling adaptor TRAM. We observed that TRAM deficient neutrophils are effectively reprogrammed into the resolving state, and can potently improve vascular integrity and suppress atherosclerosis pathogenesis when adoptively transfused into recipient atherosclerotic animals. Mechanistically, TRAM deficiency reduces the expression of LOX5AP, dislodges nuclear localization of LOX5, and favors the generation of RvD1 instead of LTB4. We also observed that human TRAM-low neutrophils are less inflammatory, as reflected in reduced swarming and reduced induction of LTB4/elastase. TRAM serves as a stress sensor of oxLDL and/or free cholesterol, triggers inflammatory signaling processes that facilitate elastase release. Our data defines a novel resolving neutrophil subset due to reduced TRAM expression which may hold therapeutic potential for reducing inflammation and treating atherosclerosis.

Cell-free supernatant of Lactococcus lactis IDCC 2301 exerts anti-inflammatory effects in LPS-induced macrophages via NF-κB and MAPK signaling pathways.

This study investigated the anti-inflammatory effects of cell-free supernatant of Lactococcus lactis IDCC 2301 on lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Expression of inflammatory mediators and cytokines, and the production of nitric oxide (NO) and prostaglandin E2 (PGE2) were qualitatively analysed. The expression of signal transductors in inflammatory cascades was quantified by western blot. Treatment with cell-free supernatant of L. lactis IDCC 2301 significantly decreased the mRNA expression levels of tumour necrosis factor (TNF-α) and interleukins including IL-1β and IL-6. The levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX-2) were also remarkably reduced in LPS-induced macrophages after the treatment. Furthermore, L. lactis IDCC 2301 reduced the levels of both dephosphorylated and phosphorylated forms of nuclear factor-kappa B (NF-κB), IκB-α, extracellular signal-regulated kinases (ERK), c-Jun amino-terminal kinases (JNK), and p38 in LPS-induced RAW 264.7 cells. Therefore, L. lactis IDCC 2301 shows anti-inflammatory activity by suppressing the NF-κB and mitogen-activated protein kinase (MAPK) signaling pathways.

Quercetin attenuates inflammation in rosacea by directly targeting p65 and ICAM-1

AimsRosacea is an inflammatory skin disease with immune and vascular dysfunction. Although there are multiple treatment strategies for rosacea, the clinical outcomes are unsatisfactory. Main methodsCombining transcriptome data and the Connectivity Map database quercetin was identified as a novel candidate for rosacea. Next, the therapeutic efficacy of quercetin was substantiated through proteomic analyses, in vivo experiments, and in vitro assays. Additionally, the utilization of DARTS, molecular docking and experimental verification revealed the therapeutic mechanisms of quercetin. Key findingsTreatment with quercetin resulted in the following effects: (i) it effectively ameliorated rosacea-like features by reducing immune infiltration and angiogenesis; (ii) it suppressed the expression of inflammatory mediators in HaCaT cells and HDMECs; (iii) it interacted with p65 and ICAM-1 directly, and this interaction resulted in the repression of NF-κB signal and ICAM-1 expression in rosacea. SignificanceWe show for the first time that quercetin interacted with p65 and ICAM-1 directly to alleviated inflammatory and vascular dysfunction, suggesting quercetin is a novel, promising therapeutic candidate for rosacea.

PM2.5 exposure upregulates pro-inflammatory protein expression in human microglial cells via oxidant stress and TLR4/NF-κB pathway

Exposure to ambient PM2.5 is associated with neurodegenerative disorders, in which microglia activation plays a critical role. Thus far, the underlying mechanisms for PM2.5-induced microglia activation have not been well elucidated. In this study, a human microglial cell line (HMC3) was used as the in vitro model to examine the inflammatory effect (hall marker of microglia activation) of PM2.5 and regulatory pathways. The expression of inflammatory mediators including interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2) as well as the brain derived neurotrophic factor (BDNF) were determined by ELISA and/or real-time PCR, respectively. Flow cytometry was used to measure the production of intracellular reactive oxygen species (ROS). Western blot was used to measure protein levels of Toll-like receptor 4 (TLR4), NF-κB inhibitor α (IκBα) and COX-2. It was shown that PM2.5 stimulation increased IL-6 and COX-2 expression but decreased BDNF expression in a dose-dependent manner. Further studies showed that PM2.5 triggered the formation of ROS and pre-treatment with the ROS scavenger acetylcysteine (NAC) significantly suppressed PM2.5-induced IL-6 and COX-2 expression. Moreover, the nuclear factor kappa B (NF-κB) inhibitor BAY11–7085 or the TLR4 neutralizing antibody markedly blocked PM2.5-induced IL-6 and COX-2 expression. However, NAC or BAY11–7085 exhibited minimal effect on PM2.5-induced BDNF down-regulation. In addition, pre-treatment with BAY11–7085 or TLR4 neutralizing antibody reduced ROS production induced by PM2.5, and NAC pre-treatment inhibited TLR4 expression and NF-κB activation induced by PM2.5. Collectively, PM2.5 treatment induced IL-6 and COX-2 but suppressed BDNF expression. PM2.5-induced IL-6 and COX-2 expression was mediated by interactive oxidative stress and TLR4/NF-κB pathway.

Molecular Mechanisms of Increased Platelets: An In Silico of the Active Compounds in Psidium guajava

Dengue virus infection causes thrombocytopenia. Psidium guajava is widely used by people to increase platelet counts. This research aims to analyze in silico the molecular mechanisms of compounds in guava fruit in increasing platelets. The compounds in guava fruit were taken from Dr. Duke's Phytochemical and Ethnobotanical Databases, which include secondary metabolites such as flavonoids, terpenoids, tannins, alkaloids, and fatty acids. Target proteins were predicted using PharmMapper. Protein interaction networks were created using STRING, visualized, and analyzed using Cytoscape. Potential target proteins were identified by topology, modularity, functional, and KEGG pathway analysis. Degree and betweenness centrality are parameters in topological analysis and the cluster with the highest score is selected as the functional module. The results showed that MAPK1, MAPK14, and AKT1 are involved in many inflammatory pathways, and MMP9 is a target protein directly involved in increasing vascular permeability. The compounds arjunolic acid, farnesene, beta-carotene, and alpha-linolenic acid inhibit MAPK1, citral, ellagic acid, palmitic acid, and oleanolic acid inhibit MAPK14, guaijaverin, pantothenic acid, and citric acid inhibit AKT1, guaijaverin and pantothenic acid inhibit MMP9. It was concluded that the bioactive compounds in guava fruit play a role in increasing platelets by inhibiting the MAPK, PI3K-Akt pathways, and leukocyte trans-endothelial migration, thereby inhibiting or reducing the production and expression of inflammatory mediators and vascular permeability.

Effects of sleep deprivation on anxiety-depressive-like behavior and neuroinflammation

BackgroundDepression is defined by a persistent low mood and disruptions in sleep patterns, with the WHO forecasting that major depression will rank as the third most prevalent contributor to the global burden of disease by the year 2030. Sleep deprivation serves as a stressor that triggers inflammation within the central nervous system, a process known as neuroinflammation. This inflammatory response plays a crucial role in the development of depression by upregulating the expression of inflammatory mediators that contribute to symptoms such as anxiety, hopelessness, and loss of pleasure. MethodsIn this study, sleep deprivation was utilized as a method to induce anxiety and depressive-like behaviors in mice. The behavioral changes in the mice were then evaluated using the EZM, EPM, TST, FST, and SPT. H&E staining and Nissl staining was used to detect morphological changes in the medial prefrontal cortical (mPFC) regions. Elisa to assess serum CORT levels. Detection of mRNA levels and protein expression of clock genes, high mobility genome box-1 (Hmgb1), silent message regulator 6 (Sirt6), and pro-inflammatory factors by RT-qPCR, Western blotting, and immunofluorescence techniques. ResultsSleep deprivation resulted in decreased exploration of unfamiliar territory, increased time spent in a state of despair, and lower sucrose water intake in mice. Additionally, sleep deprivation led to increased secretion of serum CORT and upregulation of clock genes, IL6, IL1β, TNFα, Cox-2, iNOS, Sirt6, and Hmgb1. Sleep. ConclusionsSleep deprivation induces anxiety-depressive-like behaviors and neuroinflammation in the brain. Transcription of clock genes and activation of the Sirt6/Hmgb1 pathway may contribute to inflammatory responses in the mPFC.

Overexpression of RAD54L attenuates osteoarthritis by suppressing the HIF-1α/VEGF signaling pathway: Bioinformatics analysis and experimental validation.

Osteoarthritis (OA) is a widespread chronic, progressive, degenerative joint disease that causes pain and disability. Current treatments for OA have limited effectiveness and new biomarkers need to be identified. Bioinformatics analysis was conducted to explore differentially expressed genes and DNA repair/recombination protein 54 L (RAD54L) was selected. We firstly overexpressed RAD54L in interleukin-1β (IL-1β)-induced human articular chondrocytes or in OA rats to investigate its effect on OA. Chondrocyte viability and apoptotic rate were measured by Cell Counting Kit-8 and flow cytometry, respectively. Then we evaluated OA severity in vivo by Hematoxylin-eosin staining and Osteoarthritis Research Society International standards. The expression of inflammatory mediators was tested by enzyme-linked immunosorbent assay. Finally, western blot was performed to determine the relative expression level of hypoxia-inducible factors 1α (HIF-1α) and vascular endothelial growth factor (VEGF). Overexpression of RAD54L promoted cell viability and attenuated apoptosis in IL-1β-induced human chondrocytes. A lower Osteoarthritis Research Society International score and a remarkable alleviation of chondrocyte disordering and infiltration of inflammatory cells were found in cartilage tissues of OA rats after overexpressing RAD54L. The inflammatory response induced by OA was decreased by RAD54L overexpression in vitro and in vivo. In addition, RAD54L overexpression decreased the relative expression level of HIF-1α and VEGF. Overexpression of RAD54L could attenuate OA by suppressing the HIF-1α/VEGF signaling pathway, indicating that RAD54L may be a potential treatment target for OA.

Activation of the IKK2/NF-κB pathway in VSMCs inhibits calcified vascular stiffness in CKD.

IKK2/NF-κB pathway-mediated inflammation in vascular smooth muscle cells (VSMCs) has been proposed to be an etiologic factor in medial calcification and stiffness. However, the role of the IKK2/NF-κB pathway in medial calcification remains to be elucidated. In this study, we found that chronic kidney disease (CKD) induces inflammatory pathways through the local activation of the IKK2/NF-κB pathway in VMSCs associated with calcified vascular stiffness. Despite reducing the expression of inflammatory mediators, complete inhibition of the IKK2/NF-κB pathway in vitro and in vivo unexpectedly exacerbated vascular mineralization and stiffness. In contrast, activation of NF-κB by SMC-specific IκBα deficiency attenuated calcified vascular stiffness in CKD. Inhibition of the IKK2/NF-κB pathway induced cell death of VSMCs by reducing anti-cell death gene expression, whereas activation of NF-κB reduced CKD-dependent vascular cell death. In addition, increased calcification of extracellular vesicles through the inhibition of the IKK2/NF-κB pathway induced mineralization of VSMCs, which was significantly reduced by blocking cell death in vitro and in vivo. This study reveals that activation of the IKK2/NF-κB pathway in VSMCs plays a protective role in CKD-dependent calcified vascular stiffness by reducing the release of apoptotic calcifying extracellular vesicles.

RISING STARS: Androgens and immune cell function.

Androgens can modulate immune cell function and may contribute to differences in the prevalence and severity of common inflammatory conditions. Although most immune cells are androgen targets, our understanding of how changes in androgen bioavailability can affect immune responses is incomplete. Androgens alter immune cell composition, phenotype, and activation by modulating the expression and secretion of inflammatory mediators or by altering the development and maturation of immune cell precursors. Androgens are generally associated with having suppressive effects on the immune system, but their impacts are cell and tissue context-dependent and can be highly nuanced even within immune cell subsets. In response to androgens, innate immune cells such as neutrophils, monocytes, and macrophages increase the production of the anti-inflammatory cytokine IL-10 and decrease nitric oxide production. Androgens promote the differentiation of T cell subsets and reduce the production of inflammatory mediators, such as IFNG, IL-4 and IL-5. Additionally, androgens/androgen receptor can promote the maturation of B cells. Thus, androgens can be considered as immunomodulatory agents, but further work is required to understand the precise molecular pathways that are regulated at the intersection between endocrine and inflammatory signals. This narrative review focusses on summarising our current understanding of how androgens can alter immune cell function and how this might affect inflammatory responses in health and disease.

Caffeic acid phenethyl ester inhibits neuro-inflammation and oxidative stress following spinal cord injury by mitigating mitochondrial dysfunction via the SIRT1/PGC1α/DRP1 signaling pathway

BackgroundThe treatment of spinal cord injury (SCI) has always been a significant research focus of clinical neuroscience, with inhibition of microglia-mediated neuro-inflammation as well as oxidative stress key to successful SCI patient treatment. Caffeic acid phenethyl ester (CAPE), a compound extracted from propolis, has both anti-inflammatory and anti-oxidative effects, but its SCI therapeutic effects have rarely been reported.MethodsWe constructed a mouse spinal cord contusion model and administered CAPE intraperitoneally for 7 consecutive days after injury, and methylprednisolone (MP) was used as a positive control. Hematoxylin–eosin, Nissl, and Luxol Fast Blue staining were used to assess the effect of CAPE on the structures of nervous tissue after SCI. Basso Mouse Scale scores and footprint analysis were used to explore the effect of CAPE on the recovery of motor function by SCI mice. Western blot analysis and immunofluorescence staining assessed levels of inflammatory mediators and oxidative stress-related proteins both in vivo and in vitro after CAPE treatment. Further, reactive oxygen species (ROS) within the cytoplasm were detected using an ROS kit. Changes in mitochondrial membrane potential after CAPE treatment were detected with 5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethyl-imidacarbocyanine iodide. Mechanistically, western blot analysis and immunofluorescence staining were used to examine the effect of CAPE on the SIRT1/PGC1α/DRP1 signaling pathway.ResultsCAPE-treated SCI mice showed less neuronal tissue loss, more neuronal survival, and reduced demyelination. Interestingly, SCI mice treated with CAPE showed better recovery of motor function. CAPE treatment reduced the expression of inflammatory and oxidative mediators, including iNOS, COX-2, TNF-α, IL-1β, 1L-6, NOX-2, and NOX-4, as well as the positive control MP both in vitro and in vivo. In addition, molecular docking experiments showed that CAPE had a high affinity for SIRT1, and that CAPE treatment significantly activated SIRT1 and PGC1α, with down-regulation of DRP1. Further, CAPE treatment significantly reduced the level of ROS in cellular cytoplasm and increased the mitochondrial membrane potential, which improved normal mitochondrial function. After administering the SIRT1 inhibitor nicotinamide, the effect of CAPE on neuro-inflammation and oxidative stress was reversed.On the contrary, SIRT1 agonist SRT2183 further enhanced the anti-inflammatory and antioxidant effects of CAPE, indicating that the anti-inflammatory and anti-oxidative stress effects of CAPE after SCI were dependent on SIRT1.ConclusionCAPE inhibits microglia-mediated neuro-inflammation and oxidative stress and supports mitochondrial function by regulating the SIRT1/PGC1α/DRP1 signaling pathway after SCI. These effects demonstrate that CAPE reduces nerve tissue damage. Therefore, CAPE is a potential drug for the treatment of SCI through production of anti-inflammatory and anti-oxidative stress effects.Graphical