FSTL1 aggravates OVA-induced inflammatory responses by activating the NLRP3/IL-1β signaling pathway in mice and macrophages

Poliumoside Exhibits Neuroprotective Effects against Cerebral Ischemia-Reperfusion Injury by Relieving Microglia-Mediated Neuronal Damage and Astrocytic Activation

Excessive activation of microglia contributes to neuronal damage and astrocytic activation during cerebral ischemia and hypoxia. Poliumoside (Pol) is a caffeoylated phenylpropanoid glycoside with significant anti-inflammatory and antioxidant functions. However, whether Pol can mediate microglia-mediated neurotoxicity in the ischemic brain remains nebulous. Here, a cerebral ischemia-reperfusion injury (CI/RI) mouse model was conducted to investigate Pol's role in microglial activation and neurotoxicity. We found that Pol significantly reduced neurological deficits, cerebral infarction volume, and neuronal damage in the CI/RI mouse model. Pol inhibited proinflammatory cytokines and microglial and astrocytic activation, while enhancing anti-inflammatory cytokines. Mechanistically, Pol markedly suppressed Fstl1, NF-κB phosphorylation, and the Nlrp3-Asc-Caspase1 inflammasome. In the oxygen-glucose-deprivation (OGD)-mediated BV2 microglia, Fstl1 overexpression significantly enhanced microglial activation. The conditioned medium of Fstl1-overexpressed microglia promoted astrocytic activation and neuronal injuries. However, Pol treatment or NF-κB pathway inhibition reversed Fstl1-mediated effects. In conclusion, Pol restrained microglia-modulated neuroinflammation and neurotoxicity in the cerebral hypoxic-ischemic model by restraining the Fstl1-NF-κB pathway.

P2Y6 promoted pruning of FSTL1 nerves by cutaneous macrophages to reset pain threshold and cardiac function

Hyperactivation of cutaneous macrophages promotes the development of chronic pain. Stimulation of nociceptive regions promotes neuroplasticity, which affects pain perception and related physiological responses. However, the specific mechanisms by which cutaneous macrophages sense and elicit nociceptive responses are unknown. Here, we exacerbated the reduction of systemic pain threshold after chronic heart failure (CHF) by silencing follistatin-like 1 (FSTL1), especially the abnormal cutaneous nociceptive sensation at PC6 acupoint, the site associated with cardiac involvement pain. The upregulation of P2Y6 and interleukin-27 expression is intimately linked to the activation of skin macrophages. Hyperactivation of P2Y6 receptor (P2Y6R) may be associated with MHC II M1+ macrophage polarization in PC6. Thus, P2Y6 is one of the key factors that modulate the functional polarization of skin macrophages, which may subsequently influence the expansion of the pain field. The supportive effect of CD206 M2+ macrophages on the cutaneous FSTL1+ nerves was significantly reduced. Meanwhile, FSTL1+ nerves in PC6 functionally interacted with calcitonin gene-related peptide (CGRP)+ nerves, and the overactivation of nerve growth factor (NGF) secreted by cutaneous macrophages induced CGRP+ neuropathological remodeling, which supported the enlargement of the pain sensory area. The activation of CGRP and P2X3 receptor (P2X3R), Na+/K+ ATPase (NKA), and P2X3R in the C8 DRG may be one of the molecular bases mediating cutaneous nociceptive transmission and affecting the function of the heart. Hyperactivation of NKA was consistent with decreased pain threshold and changes in cardiac dysfunction, and PC6 injection of an NKA inhibitor (digilanid C) was effective in ameliorating nociception and cardiac impairment. The beneficial effects of digilanid C were counteracted by FSTL1 silencing. These results indicated that P2Y6 mediates the remodeling of pain perception by skin macrophages via the action of FSTL1, while NKA inhibitors synergistically exert their therapeutic effects.

Host FSTL1 defines the impact of stem cell therapy on liver fibrosis by potentiating the early recruitment of inflammatory macrophages

Adult stem cell therapy holds great promise for treating decompensated liver cirrhosis on the basis of animal studies, despite uncertainty about its clinical therapeutic efficacy and unclear underlying mechanisms. Here, we investigated the role of follistatin-like 1 (FSTL1), a profibrotic and proinflammatory matricellular protein, in inflammation-related heterogeneity in stem cell therapy. Our results showed that a high level of circulating FSTL1 is significantly correlated with therapeutic response in patients with cirrhosis. FSTL1 facilitated MSC-mediated early recruitment of Ly6C+ inflammatory macrophages within 24 h postinfusion, which was essential for the empowerment of MSCs and subsequent Ly6C-CX3CR1+ macrophage remodelling at 48 h postinfusion. Fstl1 deficiency abrogated early macrophage recruitment and effective Ly6C-CX3CR1+ macrophage accumulation, resulting in the poor antifibrotic effect of MSCs in mice. Whereas, recombinant FSTL1 protein restored the therapeutic efficacy of MSCs in CCl4-injured Fstl1+/- mice. Mechanistically, host FSTL1 enhanced rapid recycling of CCR2 to the membrane via activation of the CD14/TLR4/NF-κB/ATP6V1G2 axis, leading to early recruitment of Ly6C+ monocytes /macrophages. Taken together, our findings revealed that FSTL1 is a critical regulator of the fibrotic immune microenvironment and facilitates subsequent stem cell therapy. These data suggest that FSTL1 could serve as a predictive biomarker of stem cell therapy response in patients with liver cirrhosis.

Network pharmacology prediction and molecular docking-based strategy to explore the potential mechanism of Ginseng-Schisandra Chinensis decoction against asthma

BACKGROUND

Ginseng-Schisandra chinensis (GSC) decoction has shown good efficacy in the treatment of asthma (AS), but its t mechanism in the treatment of asthma is still not fully understood.

PURPOSE

This study aims to elucidate the therapeutic mechanism of GSC for AS by identifying the active components of GSC.

METHODS

The chemical composition of GSC was analyzed using UHPLC-MS/MS. The network pharmacology method combined with TCMSP and GeneCards database was used to identify potential targets and enriched pathways related to AS treatment. Use AutoDock for molecular docking to evaluate the binding affinity of active ingredients to core targets. Finally, the LPS-induced A549 cell inflammation model was used to evaluate the effect of GSC on the release of inflammatory cytokines.

RESULTS

The main components in GSC, including ginsenosides (Rf, Rd, Rg2, Ro, Rg5, Rh1) and lignans (schisandrin A, B, schisandrol A, B, schisandrin ester A) were identified. Network analysis revealed 139 intersection targets and highlighted STAT3, TNF, EGFR, IL1B, and AKT1 as key targets, with the PI3K/AKT signaling pathway as the main pathway. Experimental results showed that GSC significantly reduced the levels of IL-1β, IL-6 and TNF-α in LPS-induced A549 cells (p < 0.01), indicating its powerful anti-inflammatory effect.

CONCLUSION

GSC plays a role in treating asthma by targeting STAT3, TNF, IL-1β and AKT1, regulating the PI3K/AKT signaling pathway and inhibiting the release of inflammatory cytokines. These findings provide a basis for the clinical application of GSC.

Fibroblast Growth Factor 21 Confers Protection Against Asthma Through Inhibition of NLRP3 Inflammasome Activation

Fibroblast growth factor 21 (FGF21) modulates the inflammatory response in a range of pathological conditions. However, whether FGF21 modulates asthma remains unexplored. This study sought to investigate its function in asthma using an ovalbumin (OVA)-induced mouse model. Levels of FGF21 were observed to be elevated in mice exhibiting asthmatic symptoms. FGF21 knockout (KO) mice exhibited exacerbated asthmatic pathologies, marked by heightened infiltration of inflammatory cells and elevated release of inflammatory cytokine, compared to wild-type (WT) mice with OVA challenge. Adeno-associated virus (AAV)-mediated overexpression of FGF21 significantly reversed asthmatic pathologies in both WT and FGF21 KO mice. Activated NLRP3 inflammasome was observed in WT mice following OVA challenge, and this response was intensified in FGF21 KO mice, manifested by an upregulation of NLRP3, ASC, cleaved Caspase-1, cleaved Gasdermin D (GSDMD), IL-1β, and IL-18. Pharmacological suppression of NLRP3 ameliorated the aggravated asthmatic pathologies observed in FGF21 KO mice after OVA challenge. Overall, the present work underscores the pivotal function of FGF21 in the pathogenesis of asthma and suggests that FGF21 could serve as a potential target for therapeutic interventions.

Role of GLCCI1 in inhibiting PI3K-induced NLRP3 inflammasome activation in asthma

Background

Glucocorticoid-induced transcript 1 (GLCCI1) has been reported to be associated with the efficiency of inhaled glucocorticoids in patients with asthma. This study aimed to investigate the role of GLCCI1 in the regulation of nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) family pyrin domain-containing 3 (NLRP3) by the phosphatidylinositol 3-kinase (PI3K) pathway in the pathogenesis of allergic asthma.

Methods

The expression levels of genes encoding GLCCI1, NLRP3 inflammasome components, and PI3K pathway-related indicators were detected in cells isolated from induced sputum from patients with asthma and healthy controls. Next, we induced asthma in wild-type C57BL/6 mice and Glcci1 knockout (Glcci1 -/-) mice by injecting them with ovalbumin (OVA) and treated the asthmatic mice with a PI3K pathway inhibitor (LY294002) or left them untreated. We also performed adoptive transfer of macrophages into the mice and assessed lung inflammation, as well as GLCCI1, PI3K pathway component, and NLRP3 inflammasome component expression levels. Finally, primary bone marrow-derived macrophages (BMDMs) from wild-type and Glcci1 -/- mice were treated with OVA, either in the presence or absence of LY294002 and the NLRP3 inhibitor (MCC950), to validate our findings.

Results

The mRNA level of Glcci1 in induced sputum cells from asthmatic patients was lower compared to that of healthy controls. Additionally, Glcci1 mRNA expression correlated negatively with NLRP3 inflammasome indicators and the PI3K pathway components, as well as with IL-1β expression in induced sputum macrophages. In vivo, Glcci1 -/- asthmatic mice showed elevated levels of airway inflammation and NLRP3 inflammasome activation compared to wild-type asthmatic mice. Surprisingly, the efficacy of LY294002 in reducing lung tissue inflammation and NLRP3 inflammasome activity in wild-type asthmatic mice was attenuated by Glcci1 knockout. LY294002 enhanced GLCCI1 levels in macrophages within the lung tissue of wild-type asthmatic mice. Moreover, LY294002 did not inhibit lung inflammation in wild-type asthmatic mice depleted of macrophages that had received adoptive transfer of Glcci1 -/- BMDMs. In vitro experiments further illustrated that LY294002 suppressed NLRP3 activation by upregulating GLCCI1 expression in BMDMs. The introduction of MCC950 led to a marked decrease in NLRP3 and apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) protein levels, but did not affect the expression levels of GLCCI1 or the phospho-protein kinase B (p-AKT)/AKT ratio.

Conclusions

GLCCI1 deficiency promotes asthma inflammation through PI3K-induced NLRP3 inflammasome activation.

IL-18 biology in severe asthma

The role of interleukin-18 (IL-18) and inflammasomes in chronic inflammatory airway diseases, such as asthma and chronic obstructive pulmonary disease (COPD), has garnered significant attention in recent years. This review aims to provide an overview of the current understanding of IL-18 biology, the associated signaling pathways, and the involvement of inflammasome complexes in airway diseases. We explore the multifaceted role of IL-18 in asthma pathophysiology, including its interactions with other cytokines and contributions to both T2 and non-T2 inflammation. Importantly, emerging evidence highlights IL-18 as a critical player in severe asthma, contributing to chronic airway inflammation, airway hyperresponsiveness (AHR), and mucus impaction. Furthermore, we discuss the emerging evidence of IL-18's involvement in autoimmunity and highlight potential therapeutic targets within the IL-18 and inflammasome pathways in severe asthma patients with evidence of infections and airway autoimmune responses. By synthesizing recent advancements and ongoing research, this review underscores the importance of IL-18 as a potential novel therapeutic target in the treatment of severe asthma and other related conditions.

The NLRP3 inflammasome in allergic diseases: mechanisms and therapeutic implications

In recent years, there has been a global increase in the prevalence of allergic diseases, including allergic rhinitis, chronic rhinosinusitis, allergic asthma, atopic dermatitis, allergic conjunctivitis, and food allergies. Since the pathogenic mechanisms of these allergic diseases are not yet fully understood, targeted and effective therapies are lacking. The NLRP3 inflammasome, a multiprotein complex implicated in various inflammatory diseases, can be activated by diverse stimuli. It assembles into NLRP3 inflammasome complexes through conformational changes, initiating the proteolytic cleavage of dormant procaspase-1 into active caspase-1 and promoting the maturation of inflammatory cytokines, including IL-1β and IL-18. Dysfunction of the NLRP3 inflammasome may serve as a key driver of inflammatory diseases, leading to pyroptosis and amplifying the local inflammatory response. As preliminarily demonstrated, specific NLRP3 inflammatory vesicle inhibitors play refectory roles in animal models of allergic diseases, and it is believed that specific NLRP3 inflammasome inhibitors may be potential therapeutic agents for allergic diseases. This review highlights the progress of research on the NLRP3 inflammasome in allergic diseases, explores its contribution to different types of allergic diseases, and identifies promising clinical targets for intervention.

Impact of ovalbumin allergy on oral and gut microbiome dynamics in 6-week-old BALB/c mice

Background

The gut microbiota is known to have a significant impact on the development of food allergy, and several recent studies have suggested that both oral microbiota, which first come into contact with allergenic foods, may have a profound influence on the development of food allergy.

Methods

In this study, we have established an ovalbumin-sensitive mice model by utilizing ovalbumin as a sensitizing agent. Subsequently, we performed a comprehensive analysis of the gut and oral microbiota in ovalbumin-sensitive mice and the control mice using full-length 16S rRNA sequencing analysis.

Results

Interestingly, both the gut and oral microbiota of ovalbumin-sensitized mice exhibited significant dysbiosis. The relative abundance of s__Lactobacillus_intestinalis in the gut microbiota of ovalbumin-sensitive mice exhibited a significant decrease, whereas the abundance of s__Agrobacterium_radiobacter and s__Acinetobacter_sp__CIP_56_2 displayed a significant increase. Furthermore, the relative abundance of s__unclassified_g__Staphylococcus, s__Streptococcus_hyointestinalis, and s__unclassified_g__Dechloromonas in the oral microbiota of ovalbumin-sensitive mice revealed a significant decrease. In contrast, the abundance of 63 other species, including s__Proteiniclasticum_ruminis, s__Guggenheimella_bovis, and s__Romboutsia_timonensis, demonstrated a significant increase. The random forest classifier achieved the best accuracy in predicting the outcome of food allergy using three gut and three oral biomarkers, with accuracies of 94.12 and 100%, respectively. Based on the predictions of the PICRUSt2 analysis, the only consistent finding observed across multiple samples from both the groups of mice was a significant up-regulation of the nucleotide-binding oligomerization domain (NOD)-like receptor signaling pathway in the ovalbumin-sensitized mice.

Conclusion

Our study demonstrates that ovalbumin-sensitized mice experience substantial alterations in both gut and oral microbial composition and structure, and specific strains identified in this study may serve as potential biomarkers for food allergy screening. Moreover, our findings highlight that the oral environment, under the same experimental conditions, exhibited greater precision in detecting a larger number of species. Additionally, it is worth noting that the NOD-like receptor signaling pathway plays a vital role in the pathogenesis of OVA (ovalbumin)-induced allergy. These findings will generate novel concepts and strategies in the realm of food allergy prevention and treatment.

FSTL1 Accelerates Nucleus Pulposus Cell Senescence and Intervertebral Disc Degeneration Through TLR4/NF-κB Pathway

Intervertebral disc degeneration (IVDD) is a major contributor to low back pain (LBP), and inflammatory factors play crucial roles in its pathogenesis. Follistatin-like 1 (FSTL1) has been reported to induce an inflammatory response in chondrocytes, microglia and preadipocytes, but its role in the pathogenesis of nucleus pulposus cell (NPC) degeneration remains unclear. In this study, we mainly utilized an acidosis-induced NPC degeneration model and a rabbit puncture IVDD model to investigate the role of FSTL1 in IVDD both in vitro and in vivo. We confirmed that FSTL1 expression significantly increased in nucleus pulposus (NP) tissues from IVDD patients and rabbit puncture IVDD models. The expression levels of FSTL1 were significantly increased in all three models of NPC degeneration under harsh microenvironments. In addition, recombinant human FSTL1 (rh-FSTL1) was found to upregulate the expression of p16 and p21, increase the number of senescence-associated β-galactosidase (SA-β-gal)-positive cells, induce senescence-related secretory phenotypes (SASP), and downregulate extracellular matrix (ECM) protein expressions, leading to an imbalance in ECM metabolism destructions. Conversely, silencing of FSTL1 by small interfering RNA (siRNA) ameliorated senescence of NPCs associated with inflammation in IVDD. Furthermore, Toll-like receptor 4/nuclear factor-κB (TLR4/NF-κB) pathway plays a crucial role in regulating NPC senescence through FSTL1 regulation. Inhibition of TLR4 expression partly reversed the effects of rh-FSTL1 on NPC senescence-associated inflammation. Finally, rabbit IVDD model experiments demonstrated that the specific FSTL1 siRNA markedly repressed the development of IVDD. These findings may offer a therapeutic approach for mitigating inflammation-induced senescence associated with IVDD.

NLRP3 inflammasome: a key player in the pathogenesis of life-style disorders

Proinflammatory cytokines and chemokines play a crucial role in regulating the inflammatory response, which is essential for the proper functioning of our immune system. When infections or threats to the body's defense mechanisms are detected, the innate immune system takes the lead. However, an excessive inflammatory response can lead to the production of high concentrations of cytotoxic molecules, resulting in tissue damage. Inflammasomes are significant contributors to innate immunity, and one of the most extensively studied inflammasome complexes is NOD-like receptor 3 (NLRP3). NLRP3 has a wide range of recognition mechanisms that streamline immune activation and eliminate pathogens. These cytosolic multiprotein complexes are composed of effector, adaptor, and sensor proteins, which are crucial for identifying intracellular bacterial breakdown products and initiating an innate immune cascade. To understand the diverse behavior of NLRP3 activation and its significance in the development of lifestyle-related diseases, one must delve into the study of the immune response and apoptosis mediated by the release of proinflammatory cytokines. In this review, we briefly explore the immune response in the context of lifestyle associated disorders such as obesity, hyperlipidemia, diabetes, chronic respiratory disease, oral disease, and cardiovascular disease.

S100A8/9 modulates perturbation and glycolysis of macrophages in allergic asthma mice

Background

Allergic asthma is the most prevalent asthma phenotype and is associated with the disorders of immune cells and glycolysis. Macrophages are the most common type of immune cells in the lungs. Calprotectin (S100A8 and S100A9) are two pro-inflammatory molecules that target the Toll-like receptor 4 (TLR4) and are substantially increased in the serum of patients with severe asthma. This study aimed to determine the effects of S100A8/A9 on macrophage polarization and glycolysis associated with allergic asthma.

Methods

To better understand the roles of S100A8 and S100A9 in the pathogenesis of allergic asthma, we used ovalbumin (OVA)-induced MH-S cells, and OVA-sensitized and challenged mouse models (wild-type male BALB/c mice). Enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction, flow cytometry, hematoxylin-eosin staining, and western blotting were performed. The glycolysis inhibitor 3-bromopyruvate (3-BP) was used to observe changes in glycolysis in mice.

Results

We found knockdown of S100A8 or S100A9 in OVA-induced MH-S cells inhibited inflammatory cytokines, macrophage polarization biomarker expression, and pyroptosis cell proportion, but increased anti-inflammatory cytokine interleukin (IL)-10 mRNA; also, glycolysis was inhibited, as evidenced by decreased lactate and key enzyme expression; especially, knockdown of S100A8 or S100A9 inhibited the activity of TLR4/myeloid differentiation primary response gene 88 (MyD88)/Nuclear factor kappa-B (NF-κB) signaling pathway. Intervention with lipopolysaccharides (LPS) abolished the beneficial effects of S100A8 and S100A9 knockdown. The observation of OVA-sensitized and challenged mice showed that S100A8 or S100A9 knockdown promoted respiratory function, improved lung injury, and inhibited inflammation; knockdown of S100A8 or S100A9 also suppressed macrophage polarization, glycolysis levels, and activation of the TLR4/MyD88/NF-κB signaling pathway in the lung. Conversely, S100A9 overexpression exacerbated lung injury and inflammation, promoting macrophage polarization and glycolysis, which were antagonized by the glycolysis inhibitor 3-BP.

Conclusion

S100A8 and S100A9 play critical roles in allergic asthma pathogenesis by promoting macrophage perturbation and glycolysis through the TLR4/MyD88/NF-κB signaling pathway. Inhibition of S100A8 and S100A9 may be a potential therapeutic strategy for allergic asthma.

ITGAM-macrophage modulation as a potential strategy for treating neutrophilic Asthma: insights from bioinformatics analysis and in vivo experiments

Identification of molecular biomarkers associated with neutrophilic asthma (NA) phenotype may inform the discovery of novel pathobiological mechanisms and the development of diagnostic markers. Three mRNA transcriptome datasets extracted from induced sputum of asthma patients with various inflammatory types were used to screen for macrophage-related molecular mechanisms and targets in NA. Furthermore, the predicted targets were also validated on an independent dataset (N = 3) and animal model (N = 5). A significant increase in total cells, neutrophils and macrophages was observed in bronchoalveolar lavage (BAL) fluid of NA mice induced by ovalbumin/freund's adjuvant, complete (OVA/CFA). And we also found elevated levels of neutrophil and macrophage infiltration in NA subtype in external datasets. NA mice had increased secretion of IgE, IL-1β, TNF-α and IL-6 in serum and BAL fluid. MPO, an enzyme present in neutrophils, was also highly expressed in NA mice. Then, weighted gene co-expression network analysis (WGCNA) identified 684 targets with the strongest correlation with NA, and we obtained 609 macrophage-related specific differentially expressed genes (DEGs) in NA by integrating macrophage-related genes. The top 10 genes with high degree values were obtained and their mRNA levels and diagnostic performance were then determined by RT-qPCR and receiver operator characteristic (ROC) analysis. Statistically significant correlations were found between macrophages and all key targets, with the strongest correlation between ITGAM and macrophages in NA. Double-Immunofluorescence staining further confirmed the co-localization of ITGAM and F4/80 in NA. ITGAM was identified as a critical target to distinguish NA from healthy/non-NA individuals, which may provide a novel avenue to further uncover the mechanisms and therapy of NA.

Endothelial extracellular vesicles induce acute lung injury via follistatin-like protein 1

Cardiopulmonary bypass has been speculated to elicit systemic inflammation to initiate acute lung injury (ALI), including acute respiratory distress syndrome (ARDS), in patients after cardiac surgery. We previously found that post-operative patients showed an increase in endothelial cell-derived extracellular vesicles (eEVs) with components of coagulation and acute inflammatory responses. However, the mechanism underlying the onset of ALI owing to the release of eEVs after cardiopulmonary bypass, remains unclear. Plasma plasminogen-activated inhibitor-1 (PAI-1) and eEV levels were measured in patients with cardiopulmonary bypass. Endothelial cells and mice (C57BL/6, Toll-like receptor 4 knockout (TLR4-/-) and inducible nitric oxide synthase knockout (iNOS-/-)) were challenged with eEVs isolated from PAI-1-stimulated endothelial cells. Plasma PAI-1 and eEVs were remarkably enhanced after cardiopulmonary bypass. Plasma PAI-1 elevation was positively correlated with the increase in eEVs. The increase in plasma PAI-1 and eEV levels was associated with post-operative ARDS. The eEVs derived from PAI-1-stimulated endothelial cells could recognize TLR4 to stimulate a downstream signaling cascade identified as the Janus kinase 2/3 (JAK2/3)-signal transducer and activator of transcription 3 (STAT3)-interferon regulatory factor 1 (IRF-1) pathway, along with iNOS induction, and cytokine/chemokine production in vascular endothelial cells and C57BL/6 mice, ultimately contributing to ALI. ALI could be attenuated by JAK2/3 or STAT3 inhibitors (AG490 or S3I-201, respectively), and was relieved in TLR4-/- and iNOS-/- mice. eEVs activate the TLR4/JAK3/STAT3/IRF-1 signaling pathway to induce ALI/ARDS by delivering follistatin-like protein 1 (FSTL1), and FSTL1 knockdown in eEVs alleviates eEV-induced ALI/ARDS. Our data thus demonstrate that cardiopulmonary bypass may increase plasma PAI-1 levels to induce FSTL1-enriched eEVs, which target the TLR4-mediated JAK2/3/STAT3/IRF-1 signaling cascade and form a positive feedback loop, leading to ALI/ARDS after cardiac surgery. Our findings provide new insight into the molecular mechanisms and therapeutic targets for ALI/ARDS after cardiac surgery.

The role of inflammasomes in human diseases and their potential as therapeutic targets

Inflammasomes are large protein complexes that play a major role in sensing inflammatory signals and triggering the innate immune response. Each inflammasome complex has three major components: an upstream sensor molecule that is connected to a downstream effector protein such as caspase-1 through the adapter protein ASC. Inflammasome formation typically occurs in response to infectious agents or cellular damage. The active inflammasome then triggers caspase-1 activation, followed by the secretion of pro-inflammatory cytokines and pyroptotic cell death. Aberrant inflammasome activation and activity contribute to the development of diabetes, cancer, and several cardiovascular and neurodegenerative disorders. As a result, recent research has increasingly focused on investigating the mechanisms that regulate inflammasome assembly and activation, as well as the potential of targeting inflammasomes to treat various diseases. Multiple clinical trials are currently underway to evaluate the therapeutic potential of several distinct inflammasome-targeting therapies. Therefore, understanding how different inflammasomes contribute to disease pathology may have significant implications for developing novel therapeutic strategies. In this article, we provide a summary of the biological and pathological roles of inflammasomes in health and disease. We also highlight key evidence that suggests targeting inflammasomes could be a novel strategy for developing new disease-modifying therapies that may be effective in several conditions.

Cordyceps militaris Solid Medium Extract Alleviates Lipoteichoic Acid-Induced MH-S Inflammation by Inhibiting TLR2/NF-κB/NLRP3 Pathways

The aim of this study was to investigate the inhibitory effects of Cordyceps militaris solid medium extract (CME) and cordycepin (COR) on LTA-induced inflammation in MH-S cells and their mechanisms of action. In this study, the establishment of an LTA-induced MH-S inflammation model was determined, the CCK-8 method was used to determine the safe concentration range for a drug for COR and CME, the optimal concentration of COR and CME to exert anti-inflammatory effects was further selected, and the expression of inflammatory factors of TNF-α, IL-1β, IL-18, and IL-6 was detected using ELISA. The relative expression of TNF-α, IL-1β, IL-18, IL-6, IL-10, TLR2 and MyD88 mRNA was detected using RT-PCR, and the IL-1β, IL-18, TLR2, MyD88, NF-κB p-p65, NLRP3, pro-caspase-1, Caspase-1 and ASC protein expression in the cells were detected using Western blot; immunofluorescence assay detected the expression of Caspase-1 in MH-S cells. The results revealed that both CME and COR inhibited the levels of IL-1β, IL-18, IL-6, and TNF-α in the supernatants of LTA-induced MH-S cells and the mRNA expression levels of IL-1β, IL-18, IL-6, TNF-α, TLR2 and MyD88, down-regulated the LTA-induced IL-1β, IL-18, TLR2 in MH-S cells, MyD88, NF-κB p-p65/p65, NLRP3, ASC, pro-caspase-1, and caspase-1 protein expression levels, and inhibited LTA-induced caspase-1 activation in MH-S cells. In conclusion, CME can play a therapeutic role in LTA-induced inflammation in MH-S cells via TLR2/NF-κB/NLRP3, and may serve as a potential drug for bacterial pneumonia caused by Gram-positive bacteria.

H3K27 acetylation-induced FSTL1 upregulation by P300/RUNX1 co-activation exacerbated autophagy-mediated neuronal damage and NF-κB-stimulated inflammation in Alzheimer's disease

Follistatin-like protein 1 (FSTL1) has been demonstrated to participate in the pathogenesis of several neurological diseases. The current study informed the role of H3K27 acetylation-induced FSTL1 upregulation in Alzheimer's disease (AD). Our investigation discovered the upregulated FSTL1 expression and enhanced autophagy activity in AD. FSTL1 knockdown successfully attenuated the injuries of Aβ1-42-challenged SH-SY5Y cells through the inhibition of autophagy activity. Besides, FSTL1 deficiency suppresses the inflammatory response and NF-κB signaling in AD. Moreover, it was found that p300 was recruited by transcriptional factor RUNX1 to stimulate the H3K27 acetylation in FSTL1 promoter region, which caused the upregulation of FSTL1 in AD. To summarize, p300 acted as a co-activator of RUNX1 to trigger the activation of FSTL1 in AD, resulting in the exacerbated injuries and inflammatory responses of Aβ1-42-induced SH-SY5Y cells.

The role of the NLRP3 inflammasome in chronic inflammation in asthma and chronic obstructive pulmonary disease

Asthma and chronic obstructive pulmonary disease (COPD) are lung diseases characterized by airflow limitation and chronic inflammation. More and more studies have shown that the occurrence and development of asthma and COPD are related to abnormal immune responses caused by dysregulation of many genetic and environmental factors. The exact pathogenesis of the disease is still unclear. A large number of studies have shown that the NLRP3 inflammasome is involved in the process of chronic airway inflammation in asthma and COPD. Here, we summarize recent advances in the mechanism of NLRP3 inflammasome activation and regulation and its role in the pathogenesis of inflammatory lung diseases such as asthma and COPD. Meanwhile we propose possible therapeutic targets in asthma and COPD.

Roles of follistatin-like protein 3 in human non-tumor pathophysiologies and cancers

Follistatin-like protein 3 (FSTL3) is a type of FSTLs. By interacting with a disintegrin and metalloproteinase 12 (ADAM12), transforming growth factor-β ligands (activin, myostatin and growth differentiation factor (GDF) 11), FSTL3 can either activate or inhibit these molecules in human non-tumor pathophysiologies and cancers. The FSTL3 gene was initially discovered in patients with in B-cell chronic lymphocytic leukemia, and subsequent studies have shown that the FSTL3 protein is associated with reproductive development, insulin resistance, and hematopoiesis. FSTL3 reportedly contributes to the development and progression of many cancers by promoting tumor metastasis, facilitating angiogenesis, and inducing stem cell differentiation. This review summarizes the current pathophysiological roles of FSTL3, which may be a putative prognostic biomarker for various diseases and serve as a potential therapeutic target.

Follistatin-related protein 1 in asthma: miR-200b-3p interactions affect airway remodeling and inflammation phenotype

Follistatin-related protein 1 (FSTL1) is significantly associated with the asthma severity and outcome in humans and diverse mouse models of asthma. Previous studies have also suggested that FSTL1 could activate autophagy and NLRP3, thus playing as a causative agent in the asthma progression. However, mechanisms that regulate airway epithelial cell-specific FSTL1 expression and function in asthma are unknown. Here, we further evaluated the spatiotemporal relationships between the FSTL1 and asthma development through ovalbumin (OVA) -induced asthma models. Integrative analysis in asthmatics airway epithelium identifies microRNA (miR)-200b-3p as a novel upstream of FSTL1. Next, we collected airway biopsies, induced sputum, and blood samples isolated from asthmatics patients and the OVA-induced mouse model. We revealed that miR-200b-3p expression is downregulated in asthmatics airway epithelium, while its expression was negatively correlated with FSTL1. On this basis, the function and expression pattern analysis of miR-200b-3p were performed using miRNA-target prediction databases and long non-coding RNA (lncRNA) microarray assay. It is illustrated that miR-200b-3p, which is downregulated with pro-fibrotic stimulation of TGF-β1, could also be sponged by lncRNA PCAT19 and regulate FSTL1 expression in asthma progression. In vivo, miR-200b-3p overexpression in mice prevents OVA-induced airway remodeling and inflammation. Lastly, protective roles of miR-200b-3p are partly attributed to the direct and functional repression of FSTL1. Our findings suggest a crucial role for the miR-200b-3p/FSTL1 axis in regulating asthmatic's airway remodeling and inflammation phenotype.