Dimethyl Fumarate Alleviates NLRP3 Inflammasome Activation in Microglia and Sickness Behavior in LPS-Challenged Mice

NLRP3 inflammasome: structure, mechanism, drug-induced organ toxicity, therapeutic strategies, and future perspectives

Drug-induced toxicity is an important issue in clinical medicine, which typically results in organ dysfunction and adverse health consequences. The family of NOD-like receptors (NLRs) includes intracellular proteins involved in recognizing pathogens and triggering innate immune responses, including the activation of the NLRP3 inflammasome. The NLRP3 (nucleotide-binding oligomerization domain-like receptor family, pyrin domain-containing 3) inflammasome is a critical component for both innate and adaptive immune responses and has been implicated in various drug-induced toxicities, including hepatic, renal, and cardiovascular diseases. The unusual activation of the NLRP3 inflammasome causes the release of pro-inflammatory cytokines, such as IL-1β and IL-18, which can lead to more damage to tissues. Targeting NLRP3 inflammasome is a potential therapeutic endeavour for suppressing drug-induced toxicity. This review provides insights into the mechanism, drug-induced organ toxicity, therapeutic strategies, and prospective therapeutic approaches of the NLRP3 inflammasome and summarizes the developing therapies that target the inflammasome unit. This review has taken up one of the foremost endeavours in understanding and inhibiting the NLRP3 inflammasome as a means of generating safer pharmacological therapies.

The (neuro)inflammatory system in anxiety disorders and PTSD: Potential treatment targets

Targeting the immune system has recently garnered attention in the treatment of stress- associated psychiatric disorders resistant to existing pharmacotherapeutics. While such approaches have been studied in considerable detail in depression, the role of (neuro)inflammation in anxiety-related disorders, or in anxiety as an important transdiagnostic symptom, is much less clear. In this review we first critically review clinical and in part preclinical evidence of central and peripheral immune dysregulation in anxiety disorders and post-traumatic stress disorder (PTSD) and briefly discuss proposed mechanisms of how inflammation can affect anxiety-related symptoms. We then give an overview of existing and potential future targets in inflammation-associated signal transduction pathways and discuss effects of different immune-modulatory drugs in anxiety-related disorders. Finally, we discuss key gaps in current clinical trials such as the lack of prospective studies involving anxiety patient stratification strategies based on inflammatory biomarkers. Overall, although evidence is rather limited so far, there is data to indicate that increased (neuro)inflammation is present in subgroups of anxiety disorder patients. Although exact identification of such immune subtypes of anxiety disorders and PTSD is still challenging, these patients will likely particularly benefit from therapeutic targeting of aspects of the inflammatory system. Different anti-inflammatory treatment approaches (microglia-directed treatments, pro-inflammatory cytokine inhibitors, COX-inhibitors, phytochemicals and a number of novel anti-inflammatory agents) have indeed shown some efficacy even in non-stratified anxiety patient groups and appear promising as novel alternative or complimentary therapeutic options in specific ("inflammatory") subtypes of anxiety disorder and PTSD patients.

Pyroptosis; igniting neuropsychiatric disorders from mild depression to aging-related neurodegeneration

Neuropsychiatric disorders significantly impact global health and socioeconomic well-being, highlighting the urgent need for effective treatments. Chronic inflammation, often driven by the innate immune system, is a key feature of many neuropsychiatric conditions. NOD-like receptors (NLRs), which are intracellular sensors, detect danger signals and trigger inflammation. Among these, NLR protein (NLRP) inflammasomes play a crucial role by releasing pro-inflammatory cytokines and inducing a particular cell death process known as pyroptosis. Pyroptosis is defined as a proinflammatory form of programmed cell death executed by cysteine-aspartic proteases, also known as caspases. Currently, the role of pyroptotic flux has emerged as a critical factor in innate immunity and the pathogenesis of multiple diseases. Emerging evidence suggests that the induction of pyroptosis, primarily due to NLRP inflammasome activation, is involved in the pathophysiology of various neuropsychiatric disorders, including depression, stress-related issues, schizophrenia, autism spectrum disorders, and neurodegenerative diseases. Within this framework, the current review explores the complex relationship between pyroptosis and neuropsychiatric diseases, aiming to identify potential therapeutic targets for these challenging conditions.

Taraxasterol mediated autophagy inhibition in pancreatic encephalopathy involves its regulation on L1 cell adhesion molecule

Pancreatic encephalopathy (PE) is a frequent complication of acute pancreatitis. This study explored the mechanism of taraxasterol (TAS) in PE treatment by inhibiting pyroptosis via L1 cell adhesion molecule (L1CAM) up-regulation. PE rat models were established and treated with TAS, NLRP3 activator, and sh-L1CAM lentivirus. Serum amylase and lipase activities and Serum, hippocampus, and amygdala IL-18 and IL-1β levels were determined by ELISA, followed by TUNEL and HE staining. Rat nerve injury was evaluated by modified Neurological Severity Score (mNSS). Spontaneous behaviors, learning, memory, and emotions in rats were separately assessed by open field, new object recognition, tail suspension, and forced swimming tests. Microstructures of hippocampal CA1 region and amygdala were observed. NLRP3 + GSDMD + cells, pyroptosis markers, L1CAM, and myelin basic protein (MBP) were detected. PE rat model displayed elevated serum amylase and lipase activities and IL-18 and IL-1β levels, increased mNSS, shortened moving distance, reduced discrimination rate, prolonged immobility time, pathological damage in hippocampal CA1 region and amygdala, increased TUNEL-positive and NLRP3 + GSDMD + cells, raised NLRP3, cleaved caspase-1, GSDMD-N, IL-1β and IL-18 levels, and reduced L1CAM and MBP levels. TAS mitigated behavioral deficits and brain injury and curbed NLRP3-mediated pyroptosis in hippocampal CA1 region and amygdala in PE rats. NLRP3 activation partly averted the beneficial impacts of TAS on PE rats. TAS suppressed nerve cell pyroptosis and facilitated myelin regeneration by up-regulating L1CAM. L1CAM silencing partially abrogated TAS's effect on behavioral deficits and brain injury in PE rats. TAS treated PE by inhibiting pyroptosis via L1CAM up-regulation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10616-025-00721-x.

Dietary Zinc activates the Nrf2 signaling pathway to inhibit pyroptosis and attenuate the lung inflammatory response in COPD

Pyroptosis and inflammation play crucial roles in the development of chronic obstructive pulmonary disease (COPD), and Zinc deficiency is commonly observed in COPD patients. In this study, we aimed to explore the impact of Zinc supplementation on pyroptosis and inflammation in a cigarette smoke (CS)-induced COPD mouse model, as well as the underlying mechanisms. The COPD mouse model was established through CS exposure, and mouse pulmonary epithelial cells (MLE-12) were exposed to cigarette smoke extract (CSE) to further validate the effects of Zinc supplementation. CS exposure resulted in significant alveolar wall damage, increased thickening of the alveolar walls, and elevated levels of interleukin-1β (IL-1β), IL-6, IL-18, and tumor necrosis factor-α (TNF-α) in the lung tissues of COPD mice. However, treatment with dexamethasone (a positive control) or Zinc supplementation alleviated these damages. Furthermore, the expressions of pyroptosis markers, including NLRP3, cleaved-Caspase-1, and GSDMD-N proteins, were upregulated in the lung tissues after CS exposure. Zinc supplementation, however, reversed these changes. Additionally, Zinc supplementation upregulated the protein expressions of nuclear factor erythroid 2-related factor 2 (Nrf2), hemeoxygenase-1 (HO-1), and quinone oxidoreductase-1 (NQO-1), and promoted the ubiquitination of Kelch-like ECH-associated protein 1 (Keap1) mediated by tripartite motif 25 (TRIM25) in the lung tissues of CS-induced mice. Importantly, the Nrf2 signaling inhibitor ML385 abolished the beneficial effects of Zinc in CS-exposed mice. Similar results were observed in MLE-12 lung epithelial cells exposed to CSE. In summary, Zinc supplementation inhibits pyroptosis and attenuates inflammation in COPD mice by activating the Nrf2 pathway.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10616-025-00725-7.

Electroacupuncture Preconditioning Attenuates Myocardial Ischemia-Reperfusion Injury in Rats Partially Through Nrf2-Mediated Reduction of Oxidative Stress and Pyroptosis

Oxidative stress and pyroptosis have been established as key contributors to myocardial ischemia-reperfusion injury (MIRI). While previous studies reported that electroacupuncture (EA) preconditioning exerted cardioprotective effects, the underlying mechanisms remain elusive. Thus, this study aimed to investigate the effects of EA preconditioning on oxidative stress and pyroptosis in MIRI rats, and explore the role of nuclear factor E2-associated factor 2 (Nrf2) throughout that process. A MIRI model was constructed by ligating the left anterior descending coronary artery for 30 min, followed by 4 h of reperfusion in rats. Prior to modeling, rats were subjected to EA at the Neiguan Point for three days. Furthermore, ML385, a Nrf2 inhibitor, was administered in order to examine the role of Nrf2 in regulating oxidative stress and pyroptosis following EA preconditioning. The results revealed that EA preconditioning improved left ventricular function after MIRI and reduced both the myocardial infarction area and cTnT levels. Meanwhile, EA preconditioning alleviated MIRI-induced oxidative stress and pyroptosis, as evidenced by the downregulation of ROS, MDA, NF-κB p65, caspase-1, IL-1β, and GSDMD-N, and the upregulation of SOD and HO-1. Mechanistically, EA up-regulated enhanced the expression of Nrf2. However, its cardioprotective effects and ability to attenuate oxidative stress and pyroptosis were suppressed by the inhibition of Nrf2. Taken together, our study indicated that EA preconditioning attenuated MIRI in rats by mitigating oxidative stress and pyroptosis, with Nrf2 playing a vital role in this protective mechanism.

Natural products target pyroptosis for ameliorating neuroinflammation: A novel antidepressant strategy

BACKGROUND

Depression is a common mental disorder characterized by prolonged loss of interest and low mood, accompanied by symptoms such as sleep disturbances and cognitive impairments. In severe cases, there may be a tendency toward suicide. Depression can be caused by a series of highly complex pathological mechanisms; However, its key pathogenic mechanism remains unclear. As a novel programmed cell death (PCD) pathway and inflammatory cell death mode, pyroptosis involves a series of tightly regulated gene expression events. It may play a significant role in the pathogenesis and management of depression by modulating neuroinflammatory processes. In addition, a large number of studies have shown that various pharmacologically active natural products can regulate pyroptosis through multiple targets and pathways, demonstrating significant potential in the treatment of depression. These natural products offer advantages such as low costs and minimal side effects, making them a viable supplement or alternative to traditional antidepressants. In this review, we summarized recent research on natural products that regulate pyroptosis and neuroinflammation to improve depression. The aim of this review was to contribute to a scientific basis for the discovery and development of more natural antidepressants in the future.

METHODS

To review the antidepressant effects of natural products targeting pyroptosis-mediated neuroinflammation, data were collected from the Web of Science, ScienceDirect databases, and PubMed to classify and summarize the relationship between pyroptosis and neuroinflammation in depression, as well as the pharmacological mechanisms of natural products.

RESULTS

Multiple researches have revealed that pyroptosis-mediated neuroinflammation serves as a pivotal contributory factor in the pathological process of depression. Natural products, such as terpenoids, terpenes, phenylethanol glycosides, and alkaloids, have antidepressant effects by regulating pyroptosis to alleviate neuroinflammation.

CONCLUSION

We comprehensively reviewed the regulatory effects of natural products in depression-related pyroptosis pathways, providing a uniquely insightful perspective for the research, development, and application of natural antidepressants. However, future research should further explore the modulatory mechanisms of natural products in regulating pyroptosis, which is of great importance for the genration of effective antidepressants.

Chronic treatment of mixture of two iridoids proportional to prescriptional dose of Yueju improves hippocampal PACAP-related neuroinflammation and neuroplasticity signaling in the LPS-induced depression model

ETHNOPHARMACOLOGICAL RELEVANCE

Geniposide (GP) and shanzhiside methyl ester (SM) are the two important bioactive compounds in the classical traditional Chinese herbal medicine Yueju Pill, which is currently used as an over-the-counter (OTC) medicine in China. Yueju has been demonstrated with antidepressant-like effects with the prescriptional dose. As GP and SM both have antidepressant potential, the synergism of them could be crucial to the function of Yueju.

OBJECTIVES

The neuropeptide pituitary adenylyl cyclase-activating polypeptide (PACAP) has been implicated in the onset of antidepressant-like response. Here we investigated the synergism of the chronic treatment with GP and SM, at proportional doses to Yueju, on antidepressant-like effects, and underlying mechanism of PACAP-related signaling in a neuroinflammation-based depression model.

MATERIALS AND METHODS

Depression-related behaviors were tested in the lipopolysaccharide (LPS)-induced depression model. The molecular signaling of neuroinflammation and neuroplasticity was investigated using Western blot analysis, immunofluorescence and pharmacological inhibition of mTOR signaling.

RESULTS

Chronic treatment of GP and SM (GS) at the dose which is proportional to the prescriptional dose of Yueju synergistically elicited antidepressant-like effects. Chronic treatment of the GS or the conventional antidepressant fluoxetine (FLX) showed antidepressant-like effects in LPS-injected mice. In vitro analysis indicated the synergism of GS on PACAP expression. In the hippocampus of LPS-injected mice, both GS and FLX enhanced PACAP expression, downregulated the inflammatory signaling of Iba-1/NF-кB/IL-1β and NLRP3, and upregulated the neuroplasticity signaling of mTOR-BDNF/PSD95. Additionally, both treatments reduced microglia activation indicated by Iba-1 immunofluorescent staining. Rapamycin, an mTOR inhibitor, blunted the antidepressant-like effects and the upregulation of BDNF expression induced by chronic GS.

CONCLUSION

The antidepressant-like effects elicited by chronic fluoxetine or by synergistic doses of GS were involved in the upregulation of hippocampal PACAP levels, in association with ameliorated neuroinflammation and neuroplasticity signaling in LPS-injected mice. GS synergism may play a key part in the antidepressant-like effects of the prescriptional dose of Yueju.

The NLRP3 inflammasome: A central player in multiple sclerosis

Multiple sclerosis (MS) is a neurological autoimmune condition associated with many symptoms including spasticity, pain, limb numbness and weakness. It is characterised by inflammatory demyelination and axonal degeneration of the brain and spinal cord. A range of disease-modifying therapies (DMTs) are available to suppress inflammatory disease activity in MS, however, there is a pressing need for new therapeutic avenues as DMTs have a limited ability to suppress confirmed disability progression. A body of literature indicates that innate immune inflammation is linked to MS progression. The nucleotide-binding oligomerization domain (NOD)-like receptor pyrin domain containing protein 3 (NLRP3) inflammasome has a well-established function in innate immunity which is closely associated with the pathogenesis of neuroinflammatory conditions. Evidence suggests that the inflammasome may be a therapeutic target in disorders such as MS and at present, inhibitors of the NLRP3 inflammasome are in pre-clinical development. Therefore, this review systematically highlights the pathogenic role of inflammasomes in MS, presenting an overview of research evidence linking inflammasome-related polymorphisms to MS susceptibility, and gathering evidence investigating NLRP3 biomarkers in MS. The role of the NLRP3 inflammasome in murine models of MS is furthermore discussed. Finally, a significant component of this review focuses on evidence that NLRP3 signalling components are novel drug targets in MS. Overall this review defines the role of the inflammasome in MS pathogenesis and identifies inflammasome inhibitor targets that warrant full investigation in MS and related disorders.

Targeting NLRP3 Inflammasomes: A Trojan Horse Strategy for Intervention in Neurological Disorders

Recently, a growing focus has been on identifying critical mechanisms in neurological diseases that trigger a cascade of events, making it easier to target them effectively. One such mechanism is the inflammasome, an essential component of the immune response system that plays a crucial role in disease progression. The NLRP3 (nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin domain containing 3) inflammasome is a subcellular multiprotein complex that is widely expressed in the central nervous system (CNS) and can be activated by a variety of external and internal stimuli. When activated, the NLRP3 inflammasome triggers the production of proinflammatory cytokines interleukin-1β (IL-1β) and interleukin-18 (IL-18) and facilitates rapid cell death by assembling the inflammasome. These cytokines initiate inflammatory responses through various downstream signaling pathways, leading to damage to neurons. Therefore, the NLRP3 inflammasome is considered a significant contributor to the development of neuroinflammation. To counter the damage caused by NLRP3 inflammasome activation, researchers have investigated various interventions such as small molecules, antibodies, and cellular and gene therapy to regulate inflammasome activity. For instance, recent studies indicate that substances like micro-RNAs (e.g., miR-29c and mR-190) and drugs such as melatonin can reduce neuronal damage and suppress neuroinflammation through NLRP3. Furthermore, the transplantation of bone marrow mesenchymal stem cells resulted in a significant reduction in the levels of pyroptosis-related proteins NLRP3, caspase-1, IL-1β, and IL-18. However, it would benefit future research to have an in-depth review of the pharmacological and biological interventions targeting inflammasome activity. Therefore, our review of current evidence demonstrates that targeting NLRP3 inflammasomes could be a pivotal approach for intervention in neurological disorders.

Caspase family in autoimmune diseases

Programmed cell death (PCD) plays a crucial role in maintaining tissue homeostasis, with its primary forms including apoptosis, pyroptosis, and necroptosis. The caspase family is central to these processes, and its complex functions across different cell death pathways and other non-cell death roles have been closely linked to the pathogenesis of autoimmune diseases. This article provides a comprehensive review of the role of the caspase family in autoimmune diseases such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), type 1 diabetes (T1D), and multiple sclerosis (MS). It particularly emphasizes the intricate functions of caspases within various cell death pathways and their potential as therapeutic targets, thereby offering innovative insights and a thorough discussion in this field. In terms of therapy, strategies targeting caspases hold significant promise. We emphasize the importance of a holistic understanding of caspases in the overall concept of cell death, exploring their unique functions and interrelationships across multiple cell death pathways, including apoptosis, pyroptosis, necroptosis, and PANoptosis. This approach transcends the limitations of previous studies that focused on singular cell death pathways. Additionally, caspases play a key role in non-cell death functions, such as immune cell activation, cytokine processing, inflammation regulation, and tissue repair, thereby opening new avenues for the treatment of autoimmune diseases. Regulating caspase activity holds the potential to restore immune balance in autoimmune diseases. Potential therapeutic approaches include small molecule inhibitors (both reversible and irreversible), biological agents (such as monoclonal antibodies), and gene therapies. However, achieving specific modulation of caspases to avoid interference with normal physiological functions remains a major challenge. Future research must delve deeper into the regulatory mechanisms of caspases and their associated complexes linked to PANoptosis to facilitate precision medicine. In summary, this article offers a comprehensive and in-depth analysis, providing a novel perspective on the complex roles of caspases in autoimmune diseases, with the potential to catalyze breakthroughs in understanding disease mechanisms and developing therapeutic strategies.

Genistein-3'-sodium sulfonate suppresses NLRP3-mediated cell pyroptosis after cerebral ischemia

Cerebral ischemia-induced pyroptosis contributes to the dissemination of neuroinflammation, and Nod-like receptor protein-3 (NLRP3) inflammasome plays a key role in this process. Previous studies have indicated that Genistein-3'-sodiumsulfonate (GSS) can inhibit neuroinflammation caused by cerebral ischemia, exert cerebroprotective effects, but its specific mechanism has not been comprehensively understood. The aim of this study was to explore the effect of GSS on ischemic stroke-induced cell pyroptosis. SD rats were randomly assigned to Sham group, transient middle cerebral artery occlusion (tMCAO) group, and tMCAO + GSS group. The open field test (OFT) was utilized to assess animals' spontaneous movement and anxiety-like behavior. Immunofluorescence was adopted to observe nod-like receptor pyrin domain containing 3 (NLRP3)/neuronal nuclei (NeuN) double-positive cells in the ischemic penumbra of each group. Western blot (WB) was conducted to detect levels of NLRP3 inflammasomes and pyroptosis-related proteins in the ischemic cortex tissue. Furthermore, the G protein-coupled estrogen receptor 1 (GPER1) inhibitor G15 was administered to monitor tMCAO rats' motor function, emotional state, and NLRP3 inflammasome activation. Compared with the Sham group, rats in the tMCAO group exhibited significant motor dysfunction and anxiety, increased NLRP3+/NeuN+ co-expressing cells in the ischemic penumbra, and elevated levels of NLRP3, apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC), pro-cysteinyl aspartate specific proteinase-1 (pro-caspase-1), cleaved-cysteinyl aspartate specific proteinase-1 (cleaved-caspase-1), gasdermin D (GSDMD), GSDMD-N-terminal domain (GSDMD-N), interleukin (IL)-1β, and IL-18 in the ischemic cortex. Treatment with GSS reversed these trends. Additionally, post G15 treatment, the therapeutic effects of GSS were reversed. GSS may inhibit NLRP3 inflammasome activation via GPER1, reducing membrane perforation and pro-inflammatory cytokine secretion, suppressing cell pyroptosis, and mitigating neuroinflammation, thereby improving chronic motor dysfunction and anxiety in tMCAO rats. Our study uncovers a potential novel mechanism for GSS treatment in ischemic stroke and provides new ideas for the treatment of ischemic stroke.

Metabolic control of microglia in health and disease

Metabolic states within cells are tightly linked to functional outcomes and finely regulated by nutrient availability. A growing body of the literature supports the idea that various metabolites can influence cellular functions, such as cell differentiation, migration, and proliferation in different contexts, with ample evidence coming from the immune system. Additionally, certain functional programs can trigger significant metabolic changes within cells, which are crucial not only to meet high energy demands, but also to produce intermediate metabolites necessary to support specific tasks. Microglia, the resident innate immune cells of the central nervous system, are constantly active, surveying the brain parenchyma and providing support to neighboring cells in the brain. They exhibit high metabolic flexibility, capable of quickly undergoing metabolic reprogramming based on nutrient availability and functional requirements. In this chapter, we will discuss the major metabolic pathways within cells and provide examples of how relevant enzymes and metabolites can impact microglial function in physiologic and pathologic contexts.

Ferroptosis in organ ischemia-reperfusion injuries: recent advancements and strategies

Ferroptosis is a newly discovered type of regulated cell death participated in multiple diseases. Different from other classical cell death programs such as necrosis and apoptosis, ferroptosis involving iron-catalyzed lipid peroxidation is characterized by Fe2+ accumulation and mitochondria alterations. The phenomenon of oxidative stress following organ ischemia-reperfusion (I/R) has recently garnered attention for its connection to the onset of ferroptosis and subsequent reperfusion injuries. This article provides a comprehensive overview underlying the mechanisms of ferroptosis, with a further focus on the latest research progress regarding interference with ferroptotic pathways in organ I/R injuries, such as intestine, lung, heart, kidney, liver, and brain. Understanding the links between ferroptosis and I/R injury may inform potential therapeutic strategies and targeted agents.

Descriptive Analysis of Patients Treated with Diroximel Fumarate and Dimethyl Fumarate-A Real-Life Experience

BACKGROUND

Dimethyl fumarate (DMF) and diroximel fumarate (DRF) are two treatments used for multiple sclerosis (MS) that have been shown to be effective in controlling MS patients. DRF was introduced in 2019 with the aim of decreasing the gastrointestinal side effects caused by DMF. Few real-life studies verify the data provided in the clinical trials.

METHODS

A retrospective descriptive study was conducted on MS patients at the Hospital Universitario Torrecárdenas under treatment with DRF and DMF. Demographic, clinical, and analytical variables were studied and compared between groups.

RESULTS

A total of 60 patients were recruited, 30 with each treatment, observing similar baseline characteristics. Fewer gastrointestinal (GI) effects were observed in the DRF group, while more infections were detected in the DMF group. We recorded lower levels in the DRF group, with four cases of moderate-severe lymphopenia in the DRF group vs. none in the DMF group. In addition, we observed a decrease in lymphocytes after the change from DMF to DRF in patients with a change.

CONCLUSIONS

Our real-life analysis of patients treated with DMF or DRF supports several studies' findings regarding decreased GI side effects with DRF vs. DMF without decreasing efficacy. However, our data show a greater reduction in lymphocytes in patients with DRF compared to DMF, so more studies are necessary.

The emerging role of microglia in the development and therapy of multiple sclerosis

Microglia are innate immune cells that maintain homeostasis of the central nervous system (CNS) and affect various neurodegenerative diseases, especially multiple sclerosis (MS). MS is an autoimmune disease of the CNS characterized by persistent inflammation, diffuse axonal damage, and microglia activation. Recent studies have shown that microglia are extremely related to the pathological state of MS and play an important role in the development of MS. This article reviews the multiple roles of microglia in the progression of MS, including the regulatory role of microglia in inflammation, remyelination, oxidative stress, the influence of phagocytosis and antigen-presenting capacity of microglia, and the recent progress by using microglia as a target for MS therapy. Microglia modulation may be a potential way for better MS therapy.

Inflammasomes in neurodegenerative diseases

Inflammasomes represent a crucial component of the innate immune system, which respond to threats by recognizing different molecules. These are known as pathogen-associated molecular patterns (PAMPs) or host-derived damage-associated molecular patterns (DAMPs). In neurodegenerative diseases and neuroinflammation, the accumulation of misfolded proteins, such as beta-amyloid and alpha-synuclein, can lead to inflammasome activation, resulting in the release of interleukin (IL)-1β and IL-18. This activation also induces pyroptosis, the release of inflammatory mediators, and exacerbates neuroinflammation. Increasing evidence suggests that inflammasomes play a pivotal role in neurodegenerative diseases. Therefore, elucidating and investigating the activation and regulation of inflammasomes in these diseases is of paramount importance. This review is primarily focused on evidence indicating that inflammasomes are activated through the canonical pathway in these diseases. Inflammasomes as potential targets for treating neurodegenerative diseases are also discussed.

Multitarget Effects of Nrf2 Signalling in the Brain: Common and Specific Functions in Different Cell Types

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a crucial regulator of cellular defence mechanisms, essential for maintaining the brain's health. Nrf2 supports mitochondrial function and protects against oxidative damage, which is vital for meeting the brain's substantial energy and antioxidant demands. Furthermore, Nrf2 modulates glial inflammatory responses, playing a pivotal role in preventing neuroinflammation. This review explores these multifaceted functions of Nrf2 within the central nervous system, focusing on its activity across various brain cell types, including neurons, astrocytes, microglia, and oligodendrocytes. Due to the brain's vulnerability to oxidative stress and metabolic challenges, Nrf2 is emerging as a key therapeutic target to enhance resilience against oxidative stress, inflammation, mitochondrial dysfunction, and demyelination, which are central to many neurodegenerative diseases.

Targeting glycolysis for neuroprotection in early LPS-induced neuroinflammation

Neuroinflammation is a pathophysiological feature of numerous neurological and psychiatric disorders. The immune response in the central nervous system, driven by microglia and astrocytes, leads to metabolic reprogramming towards aerobic glycolysis, a phenomenon known as the Warburg effect. The control of metabolic reprogramming via immunomodulation may represent a potential therapeutic target for providing protection against neuroinflammation, which contributes to neuronal dysfunction and death in several neurological disorders. For this purpose, we investigated putative neuroprotective effects of the downregulation of aerobic glycolysis using the 3PO inhibitor, and the downregulation of neuroinflammation using MCC950, in the early LPS-induced neuroinflammation model. The LPS-induced shift towards glycolysis, inflammatory and glial changes (IL-1β, NF-κB, COX2, Iba1, GFAP) were reversed by 3PO, which improved animal behavior. Additionally, MCC950 (an NLRP3 inhibitor) downregulated TLR4/Akt/p38 MAPK/NF-κB/STAT3 signaling, expressions of COX2 and IL-1β, and the astrocyte reactivity (decreasing GFAP) induced by early neuroinflammation, resulting in low glucose uptake. Our data support the occurrence of the Warburg effect during early neuroinflammation and suggest potential new approaches for the treatment of brain injury, given the role of neuroinflammation in such events.

Microglial Mayhem NLRP3 Inflammasome's Role in Multiple Sclerosis Pathology

INTRODUCTION

This review delves into the intricate relationship between NLR inflammasomes, particularly the NLRP3 inflammasome, and the immune-mediated neurodegenerative disease, multiple sclerosis (MS). While the precise etiology of MS remains elusive, compelling research underscores the pivotal role of the immune response in disease progression. Notably, recent investigations highlight the significant involvement of NLRP3 inflammasomes in various autoimmune diseases, prompting an in-depth exploration of their impact on MS.

METHOD

The review focuses on elucidating the activation mechanism of NLRP3 inflammasomes within microglia/macrophages (MG/MФ), examining how this activation promotes an inflammatory response that exacerbates neuronal damage in MS. A comprehensive analysis of existing literature and research findings forms the basis for understanding the intricate interplay between NLRP3 inflammasomes and MS pathogenesis.

RESULTS

Synthesizing current research, the review provides insight into the pivotal role played by NLR inflammasomes, specifically NLRP3, in MS. Emphasis is placed on the inflammatory response orchestrated by activated MG/MФ, elucidating the cascade that perpetuates neuronal damage in the disease.

CONCLUSIONS

This review concludes by consolidating key findings and offering a nuanced perspective on the role of NLRP3 inflammasomes in MS pathogenesis. The detailed exploration of the activation process within MG/MФ provides a foundation for understanding the disease's underlying mechanisms. Furthermore, the review sets the stage for potential therapeutic strategies targeting NLRP3 inflammasomes in the pursuit of MS treatment.

Understanding Multiple Sclerosis Pathophysiology and Current Disease-Modifying Therapies: A Review of Unaddressed Aspects

Multiple sclerosis (MS) is a complex autoimmune disorder of the central nervous system (CNS) with an unknown etiology and pathophysiology that is not completely understood. Although great strides have been made in developing disease-modifying therapies (DMTs) that have significantly improved the quality of life for MS patients, these treatments do not entirely prevent disease progression or relapse. Identifying the unaddressed pathophysiological aspects of MS and developing targeted therapies to fill in these gaps are essential in providing long-term relief for patients. Recent research has uncovered some aspects of MS that remain outside the scope of available DMTs, and as such, yield only limited benefits. Despite most MS pathophysiology being targeted by DMTs, many patients still experience disease progression or relapse, indicating that a more detailed understanding is necessary. Thus, this literature review seeks to explore the known aspects of MS pathophysiology, identify the gaps in present DMTs, and explain why current treatments cannot entirely arrest MS progression.

Gypenosides alleviates HaCaT keratinocyte hyperproliferation and ameliorates imiquimod-induced psoriasis in mice

BACKGROUND

Psoriasis is an autoimmune skin condition characterized by hyperproliferation of keratinocytes and chronic immune responses. Gypenosides (Gyp) exhibits anti-proliferative and anti-inflammatory effects on different diseases. However, its functioning and mechanism of Gyp on psoriasis remains unknown.

OBJECTIVE

To explore the effect and mechanism of Gyp on psoriasis.

MATERIAL AND METHODS

The impact and mechanism of Gyp on psoriasis in vitro and in vivo were probed through cell counting kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU) incorporation assay, reverse transcription quantitative polymerase chain reaction, hematoxylin and eosin staining, enzyme-linked immunosorbent serologic assay, immunofluorescence, and Western Blotting assays.

RESULTS

Gyp inhibited cell proliferation and the release of inflammatory cytokinesin interleukin (IL-22)-induced spontaneously transformed human aneuploid immortal keratinocyte cell line (HaCaT). In addition, Gyp demonstrated enhancement in erythema and scaling as well as reductions in the thickness of epidermal layers, release of inflammatory factors, and Ki-67 (a nuclear protein) level in imiquimod (IMQ)-induced mice. Mechanistically, Gyp upregulated nuclear factor erythroid 2-related factor 2 (Nrf-2) expression and diminished the level of p-p65/p65 and p-STAT3/STAT3 in skin tissues from IMQ-induced mice and IL-22-induced HaCaT cells, which were reversed with the application of ML385, an inhibitor of Nrf2. In addition, the administration of ML385 reversed decrease in cell viability and reduced the expressions of IL-1β, IL-6, and tumor necrosis factor-α (TNF-α) in IL-22-induced HaCaT cells caused by Gyp.

CONCLUSION

In summary, Gyp reduced excessive cell growth and inflammation in psoriasis by suppressing nuclear factor kappa B (NF-κB) and signal transducer and activator of transcription 3 (STAT3) through activation of Nrf2.

Pyroptosis: An Accomplice in the Induction of Multisystem Complications Triggered by Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is a common respiratory disorder, primarily characterized by two pathological features: chronic intermittent hypoxia (CIH) and sleep deprivation (SD). OSA has been identified as a risk factor for numerous diseases, and the inflammatory response related to programmed cell necrosis is believed to play a significant role in the occurrence and progression of multisystem damage induced by OSA, with increasing attention being paid to pyroptosis. Recent studies have indicated that OSA can elevate oxidative stress levels in the body, activating the process of pyroptosis within different tissues, ultimately accelerating organ dysfunction. However, the molecular mechanisms of pyroptosis in the multisystem damage induced by OSA remain unclear. Therefore, this review focuses on four major systems that have received concentrated attention in existing research in order to explore the role of pyroptosis in promoting renal diseases, cardiovascular diseases, neurocognitive diseases, and skin diseases in OSA patients. Furthermore, we provide a comprehensive overview of methods for inhibiting pyroptosis at different molecular levels, with the goal of identifying viable targets and therapeutic strategies for addressing OSA-related complications.

Acute exposure to LPS induces cardiac dysfunction via the activation of the NLRP3 inflammasome

Systemic inflammation contributes to left ventricular (LV) dysfunction, however the role of the NLRP3 inflammasome in LV dysfunction in acute inflammatory conditions is unclear. This study investigated the role of the NLRP3 inflammasome in acute (24 h) cardiac structural and functional changes in vivo and in vitro in lipopolysaccharide (LPS)-induced inflammation. LPS-treated Sprague-Dawley (SD) rats showed increased LPS metabolite abundance in their LVs as measured by atmospheric pressure matrix-assisted laser desorption ionisation (AP-MALDI) mass spectrometry imaging (MSI). Echocardiography and histology showed that in LPS-exposed rats, LV internal diameter was decreased, with evidence of macrophage infiltration and oedema. However, there were no changes in LV wall thickness or collagen volume. Additionally, LPS-exposed rats exhibited impaired LV relaxation, potentially contributing to decreased stroke volume. While global systolic function was preserved, LPS exposure in SD rats resulted in impaired myocardial deformation assessed by speckle-tracking echocardiography. Exposure to LPS resulted in upregulation of the expression of components of the NLRP3 inflammasome in rodents. In vitro LPS exposure resulted in increased gene expression of NLRP3 and downstream cytokines IL-1β and IL-18, antioxidant SOD2, and elevated markers of pyroptosis (GSDMD) which were inhibited by treatment with a NLRP3 antagonist. However, LPS-induced increases in the gene expression of apoptosic markers (BAX/Bcl2) were not impacted by NLRP3 antagonism. These findings suggest that inflammation induced adverse cardiac structural and functional changes is, at least in part, mediated by the NLRP3 inflammasome in acute, high-grade inflammatory states. In addition, in vitro findings suggest that while the NLRP3 inflammasome mediates pyroptotic pathways, regulation of apoptosis that is independent of the inflammasome.

Nrf2 deficiency exacerbated pulmonary pyroptosis in maternal hypoxia-induced intrauterine growth restriction offspring mice

Maternal prenatal hypoxia is an important contributor to intrauterine growth restriction (IUGR), which impedes fetal lung maturation and leads to the development of chronic lung diseases. Although evidence suggests the involvement of pyroptosis in IUGR, the molecular mechanism of pyroptosis is still unclear. Nuclear factor erythroid 2-related factor 2 (Nrf2) has been found to potentially interact with gasdermin D (GSDMD), the key protein responsible for pyroptosis, indicating its crucial role in inhibiting pyroptosis. Therefore, we hypothesized that Nrf2 deficiency is a key molecular responsible for lung pyroptosis in maternal hypoxia-induced IUGR offspring mice. Pregnant WT and Nrf2-/- mice were exposed to hypoxia (10.5 % O2) to mimic IUGR model. We assessed body weight, lung histopathology, pulmonary angiogenesis, oxidative stress levels, as well as mRNA and protein expressions related to inflammation in the 2-week-old offspring. Additionally, we conducted a dual-luciferase reporter assay to confirm the targeting relationship between Nrf2 and GSDMD. Our findings revealed that offspring with maternal hypoxia-induced IUGR exhibited reduced birth weight, catch-up growth delay, and pulmonary dysplasia. Furthermore, we observed impaired nuclear translocation of Nrf2 and increased GSDMD-mediated pyroptosis in these offspring with IUGR. Moreover, the dual-luciferase reporter assay demonstrated that Nrf2 could directly inhibit GSDMD transcription; deficiency of Nrf2 exacerbated pyroptosis and pulmonary dysplasia in offspring with maternal hypoxia-induced IUGR. Collectively, our findings suggest that Nrf2 deficiency induces GSDMD-mediated pyroptosis and pulmonary dysplasia in offspring with maternal hypoxia-induced IUGR; thus highlighting the potential therapeutic approach of targeting Nrf2 for treating prenatal hypoxia-induced pulmonary dysplasia in offspring.

Dimethyl fumarate ameliorates chronic stress-induced anxiety-like behaviors by decreasing neuroinflammation and neuronal activity in the amygdala

BACKGROUND

Chronic stress-induced neuroinflammation plays a pivotal role in the development and exacerbation of mental disorders, such as anxiety and depression. Dimethyl Fumarate (DMF), an effective therapeutic agent approved for the treatment of multiple sclerosis, has been widely reported to display anti-inflammatory and anti-oxidative effects. However, the impact of DMF on chronic stress-induced anxiety disorders and the exact underlying mechanisms remain largely unknown.

METHODS

We established a mouse model of chronic social defeat stress (CSDS). DMF was administered orally 1 h before daily stress session for 10 days in CSDS + DMF group. qRT-PCR and western blotting were used to analyze mRNA and protein expression of NLRP3, Caspase-1 and IL-1β. Immunofluorescence staining was carried out to detect the expression of Iba 1 and c-fos positive cells as well as morphological change of Iba 1+ microglia. Whole-cell patch-clamp recording was applied to evaluate synaptic transmission and intrinsic excitability of neurons.

RESULTS

DMF treatment significantly alleviated CSDS-induced anxiety-like behaviors in mice. Mechanistically, DMF treatment prevented CSDS-induced neuroinflammation by inhibiting the activation of microglia and NLRP3/Caspase-1/IL-1β signaling pathway in basolateral amygdala (BLA), a brain region important for emotional processing. Furthermore, DMF treatment effectively reversed the CSDS-caused disruption of excitatory and inhibitory synaptic transmission balance, as well as the increased intrinsic excitability of BLA neurons.

CONCLUSIONS

Our findings provide new evidence that DMF may exert anxiolytic effect by preventing CSDS-induced activation of NLRP3/Caspase-1/IL-1β signaling pathway and alleviating hyperactivity of BLA neurons.

Discovery and verification of antidepressant active ingredients of raw and vinegar-processed Bupleurum marginatum var. Stenophyllum based on plant metabolomics and serum pharmacology

The dried root of Bupleurum marginatum var. stenophyllum (H. Wolff) R.H. Shan & Y. Li (BM), which has been used as a Bupleuri radix in Guizhou Province and is listed in the 2003 edition of the Guizhou Quality Standard for Traditional Chinese Medicines and Ethnic Materia Medica, is effective at dispersing the liver and relieving depression and often used in the form of raw or vinegar-processed product (VBM). However, the potential depression-relieving components of BM are unclear. The aim of this study was to determine the potential antidepressant constituents of BM and investigate the effect of vinegar processing on these components. The antidepressant effect and mechanism of BM and VBM were investigated in depressed mice and BV2 cells, respectively. The pharmacodynamic constituents were screened through serum pharmacochemistry, which combined the results of metabolomics analysis of BM and VBM, high-performance liquid chromatography (HPLC) content determination, and verification of the antidepressant effect and mechanism of differential components of SSb2 to clarify the connotation of vinegar processing. Our results demonstrated that BM can exert a significant antidepressant effect by inhibiting microglia polarization and that this effect was enhanced after vinegar processing. Thirty-eight components were identified in the BM, 13 of which were blood-absorbable, mainly saponins, and defined as potential antidepressant components of the BM. The contents of 17 components-6 of which were absorbed into the blood-changed considerably after processing. It was finally determined that vinegar processing can enhance the antidepressant effect of BM by increasing the contents of SSb1 and SSb2. SSb2 exerts this effect via the samemechanism as BM. In conclusion, in this study we clarified the antidepressant effects and potential active components of BM and examined the mechanism of vinegar processing. These findings lay a foundation for the future research on the antidepressant effects of BM as well as for the complete development and application of BM's ethnomedicinal resources.

Lupenone improves motor dysfunction in spinal cord injury mice through inhibiting the inflammasome activation and pyroptosis in microglia via the nuclear factor kappa B pathway

JOURNAL/nrgr/04.03/01300535-202408000-00034/figure1/v/2023-12-16T180322Z/r/image-tiff Spinal cord injury-induced motor dysfunction is associated with neuroinflammation. Studies have shown that the triterpenoid lupenone, a natural product found in various plants, has a remarkable anti-inflammatory effect in the context of chronic inflammation. However, the effects of lupenone on acute inflammation induced by spinal cord injury remain unknown. In this study, we established an impact-induced mouse model of spinal cord injury, and then treated the injured mice with lupenone (8 mg/kg, twice a day) by intraperitoneal injection. We also treated BV2 cells with lipopolysaccharide and adenosine 5'-triphosphate to simulate the inflammatory response after spinal cord injury. Our results showed that lupenone reduced IκBα activation and p65 nuclear translocation, inhibited NLRP3 inflammasome function by modulating nuclear factor kappa B, and enhanced the conversion of proinflammatory M1 microglial cells into anti-inflammatory M2 microglial cells. Furthermore, lupenone decreased NLRP3 inflammasome activation, NLRP3-induced microglial cell polarization, and microglia pyroptosis by inhibiting the nuclear factor kappa B pathway. These findings suggest that lupenone protects against spinal cord injury by inhibiting inflammasomes.

Monosodium Urate Crystal-Induced Pyroptotic Cell Death in Neutrophil and Macrophage Facilitates the Pathological Progress of Gout

Monosodium urate (MSU) crystal deposition in joints can lead to the infiltration of neutrophils and macrophages, and their activation plays a critical role in the pathological progress of gout. However, the role of MSU crystal physicochemical properties in inducing cell death in neutrophil and macrophage is still unclear. In this study, MSU crystals of different sizes are synthesized to explore the role of pyroptosis in gout. It is demonstrated that MSU crystals induce size-dependent pyroptotic cell death in bone marrow-derived neutrophils (BMNs) and bone marrow-derived macrophages (BMDMs) by triggering NLRP3 inflammasome-dependent caspase-1 activation and subsequent formation of N-GSDMD. Furthermore, it is demonstrated that the size of MSU crystal also determines the formation of neutrophil extracellular traps (NETs) and aggregated neutrophil extracellular traps (aggNETs), which are promoted by the addition of interleukin-1β (IL-1β). Based on these mechanistic understandings, it is shown that N-GSDMD oligomerization inhibitor, dimethyl fumarate (DMF), inhibits MSU crystal-induced pyroptosis in BMNs and J774A.1 cells, and it further alleviates the acute inflammatory response in MSU crystals-induced gout mice model. This study elucidates that MSU crystal-induced pyroptosis in neutrophil and macrophage is critical for the pathological progress of gout, and provides a new therapeutic approach for the treatment of gout.

Free total rhubarb anthraquinones protect intestinal mucosal barrier of SAP rats via inhibiting the NLRP3/caspase-1/GSDMD pyroptotic pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Rhubarb is the peeled and dried roots of Rheum palmatum L. and Rheum tanguticum Maxim. ex Balf. or Rheum officinale Baill. Free total rhubarb anthraquinones (FTRAs) were isolated and extracted from rhubarb. Previous studies have revealed that the early administration of FTRAs protects the intestinal mucosal barrier in rats with severe acute pancreatitis (SAP), the mechanism of which is not yet clear. However, we observed an enhanced expression of intestinal pyroptotic factors in rats treated with SAP, which may be related to the mechanism of intestinal barrier protection by FTRAs.

AIM OF THE STUDY

The main objective of this study was to investigate the mechanism by which FTRAs protect the intestinal mucosal barrier in SAP rats, focusing on the classical pyroptosis pathway.

MATERIALS AND METHODS

SAP was induced in rats through retrograde injection of sodium taurocholate via the pancreaticobiliary duct. Subsequently, FTRAs (22.5, 45, and 90 mg/kg), rhubarb (900 mg/kg, positive control), and saline (control) were administered at 0 h (immediately), 12 h, and 24 h post-surgery. Pancreatic and intestinal tissue injury, positive PI staining rate, and expression levels of various factors in intestinal tissues were compared across different groups. These factors include diamine oxidase (DAO), lactate dehydrogenase (LDH), high mobility group box chromosomal protein 1(HMGB1) and pro-inflammatory factors in intestinal and serum, pyroptosis-associated factors, toll-like receptor 4 (TLR-4), nuclear factor kappa-B (NF-kB), apoptosis-associated speck-like protein (ASC), NOD-like receptor protein 3 (NLRP3), cysteine protease-1 (caspase-1) and Gasdermin (GSDMD).

RESULTS

The findings indicated that FTRAs protected the damaged intestine and pancreas and restored the expression of intestinal epithelial junction proteins in SAP rats. Additionally, it reduced intestinal and serum levels of DAO, interleukin 1, interleukin 18, HMGB1, and LDH, attenuated intestinal Positive PI staining rate, and significantly decreased the expressions of TLR-4, NF-kB, ASC, NLRP3, caspase-1 and GSDMD in SAP rats.

CONCLUSIONS

The results suggest that FTRAs inhibited pyroptosis through down-regulation of the NLRP3-Caspase-1-GSDMD and TLR-4- NF-kB signaling pathways of intestinal tissues., thereby protecting the intestinal barrier of SAP rats.

Dimethyl fumarate covalently modifies Cys673 of NLRP3 to exert anti-inflammatory effects

The NLRP3 inflammasome plays a pivotal role in various chronic inflammation-driven human diseases. However, no drugs specifically targeting NLRP3 inflammasome have been approved by the Food and Drug Administration (FDA) of the United States. In our current study, we showed that dimethyl fumarate (DMF) efficiently suppressed the activation of the NLRP3 inflammasome induced by multiple agonists and covalently modified Cys673 of NLRP3, thereby impeding the interaction between NLRP3 and NEK7. The inhibitory effect of DMF was nullified by anaplerosis of the Cys673 mutant (but not the wild-type) NLRP3 in Nlrp3-/- THP-1 cells. In vivo experiments, DMF demonstrated protective effects in the dextran sodium sulfate (DSS)-induced ulcerative colitis of WT mice, but not in Nlrp3-/- mice. In summary, our study identified DMF as a direct covalent inhibitor of NLRP3 and a potential candidate for the treatment of NLRP3 inflammasome-mediated diseases.

Dimethyl fumarate induces cardiac developmental toxicity in zebrafish via down-regulation of oxidative stress

Dimethyl fumarate (DMF) is an immunosuppressant commonly used to treat multiple sclerosis and other autoimmune diseases. Despite known side effects such as lymphopenia, the effect of DMF on cardiac development remains unclear. To assess this, we used zebrafish to evaluate the cardiac developmental toxicity of DMF. Our study showed that DMF reduced the survival rate of zebrafish embryos, with those exposed to 1, 1.3, and 1.6 mg/L exhibiting heart rate reduction, shortened body length, delayed yolk sac absorption, pericardial edema, increased distance from sinus venous to bulbus arteriosus, and separation of cardiomyocytes and endocardial cells at 72 hpf. Heart development-related genes showed disorder, apoptosis-related genes were up-regulated, and the oxidative stress response was down-regulated. Treatment with cysteamine ameliorated the heart development defects. Our study demonstrates that DMF induces cardiac developmental toxicity in zebrafish, possibly by down-regulating oxidative stress responses. This study provides a certain research basis for further study of DMF-induced cardiac developmental toxicity, and provides some experimental evidence for future clinical application and study of DMF.

METTL3 Mediates Microglial Activation and Blood-Brain Barrier Permeability in Cerebral Ischemic Stroke by Regulating NLRP3 Inflammasomes Through m6A Methylation Modification

Cerebral ischemic stroke (CIS) is the main cause of disability. METTL3 is implicated in CIS, and we explored its specific mechanism. Middle cerebral artery occlusion (MCAO) rat model and oxygen-glucose deprivation/reperfusion (OGD/R) HAPI cell model were established and treated with LV-METTL3 or DAA, oe-METTL3, miR-335-3p mimics, or DAA, to assess their effects on MCAO rat neurological and motor function, cerebral infarction area, brain water content, microglial activation, blood-brain barrier (BBB) permeability, and NLRP3 inflammasome activation. METTL3, pri-miR-335-3p, mature miR-335-3p, and miR-335-3p mRNA levels were assessed by RT-qPCR; M1/M2 microglial phenotype proportion and M1/M2 microglia ratio, inflammatory factor levels, and m6A modification were assessed. MCAO rats manifested cerebral ischemia injury. METTL3 was under-expressed in CIS. METTL3 overexpression inhibited microglial activation and M1 polarization and BBB permeability in MCAO rats and inhibited OGD/R-induced microglial activation and reduced M1 polarization. METTL3 regulated miR-335-3p expression and inhibited NLRP3 inflammasome activation. m6A methylation inhibition averted METTL3's effects on NLRP3 activation, thus promoting microglial activation in OGD/R-induced cells and METTL3's effects on BBB permeability in MCAO rats. Briefly, METTL3 regulated miR-335-3p expression through RNA m6A methylation and inhibited NLRP3 inflammasome activation, thus repressing microglial activation, BBB permeability, and protecting against CIS.

A review of the pharmacological action and mechanism of natural plant polysaccharides in depression

Depression is a prevalent mental disorder. However, clinical treatment options primarily based on chemical drugs have demonstrated varying degrees of adverse reactions and drug resistance, including somnolence, nausea, and cognitive impairment. Therefore, the development of novel antidepressant medications that effectively reduce suffering and side effects has become a prominent area of research. Polysaccharides are bioactive compounds extracted from natural plants that possess diverse pharmacological activities and medicinal values. It has been discovered that polysaccharides can effectively mitigate depression symptoms. This paper provides an overview of the pharmacological action and mechanisms, intervention approaches, and experimental models regarding the antidepressant effects of polysaccharides derived from various natural sources. Additionally, we summarize the roles and potential mechanisms through which these polysaccharides prevent depression by regulating neurotransmitters, HPA axis, neurotrophic factors, neuroinflammation, oxidative stress, tryptophan metabolism, and gut microbiota. Natural plant polysaccharides hold promise as adjunctive antidepressants for prevention, reduction, and treatment of depression by exerting their therapeutic effects through multiple pathways and targets. Therefore, this review aims to provide scientific evidence for developing polysaccharide resources as effective antidepressant drugs.

Fisetin suppresses ferroptosis through Nrf2 and attenuates intervertebral disc degeneration in rats

Low back pain, primarily caused by intervertebral disc degeneration (IVDD), lacks effective pharmacological treatments. Oxidative stress has been identified as a significant contributor to IVDD. This study aims to establish an in vitro model of IVDD induced by oxidative stress and identify potential therapeutic agents and their underlying mechanisms. By screening the natural product library, fisetin emerged as the most promising compound in suppressing cell death induced by oxidative stress in nucleus pulposus cells (NPCs). Furthermore, our investigation revealed that the cell death induced by oxidative stress was predominantly associated with ferroptosis, and fisetin demonstrated the ability to inhibit ferroptosis in NPCs. Mechanistic exploration suggested that the impact of fisetin on ferroptosis may be mediated through the Nrf2/HO-1 (Nuclear factor erythroid 2-related factor 2/heme oxygenase-1) axis. Notably, the in vivo study demonstrated that fisetin could alleviate IVDD in rats. These findings highlight fisetin as a potential therapeutic option for IVDD and implicate the involvement of the Nrf2/HO-1 pathway in its mechanism of action.

JE-133 Suppresses LPS-Induced Neuroinflammation Associated with the Regulation of JAK/STAT and Nrf2 Signaling Pathways

Neuroinflammation plays an important role in the pathogenesis of neurodegenerative diseases, and interrupting the microglial-mediated neuroinflammation has been suggested as a promising strategy to delay or prevent the progression of neurodegeneration. In this study, we investigated the effects of JE-133, an optically active isochroman-2H-chromene conjugate containing a 1,3-disubstituted isochroman unit, on lipopolysaccharide (LPS)-induced microglial neuroinflammation and underlying mechanisms both in vitro and in vivo. First, JE-133 treatment decreased LPS-induced overproduction of interleukin-1 beta (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), nitrite, and nitric oxide synthase (iNOS) in BV2 microglial cells. Further study revealed that JE-133 downregulated the phosphorylation level of JAK/STAT and upregulated the protein level of Nrf2/HO-1 in LPS-stimulated BV2 microglial cells and verified that JE-133 directly bound to Keap1 by a pull-down assay. Next, JE-133 administration also inhibited neuroinflammation in vivo, as indicated by a reduced CD11b protein level and an overexpressed mRNA level of the pro-inflammatory cytokine TNF-α in the hippocampus of LPS-injected mice. Moreover, the regulative effects of JE-133 on the JAK/STAT and Nrf2/HO-1 pathways were also verified in the hippocampus of LPS-injected mice. Taken together, our study for the first time reports that JE-133 exhibits inhibitory effects against LPS-stimulated neuroinflammation both in vitro and in vivo, which might be associated with the simultaneous regulation of the JAK/STAT and Nrf2 pathways. Our findings may provide important clues for the discovery of effective drug leads/candidates against neuroinflammation-associated neurodegeneration.

NLRP3 inflammatory pathway. Can we unlock depression?

Depression holds the title of the largest contributor to worldwide disability, with the numbers expected to continue growing. Currently, there are neither reliable biomarkers for the diagnosis of the disease nor are the current medications sufficient for a lasting response in nearly half of patients. In this comprehensive review, we analyze the previously established pathophysiological models of the disease and how the interplay between NLRP3 inflammasome activation and depression might offer a unifying perspective. Adopting this inflammatory theory, we explain how NLRP3 inflammasome activation emerges as a pivotal contributor to depressive inflammation, substantiated by compelling evidence from both human studies and animal models. This inflammation is found in the central nervous system (CNS) neurons, astrocytes, and microglial cells. Remarkably, dysregulation of the NLRP3 inflammasome extends beyond the CNS boundaries and permeates into the enteric and peripheral immune systems, thereby altering the microbiota-gut-brain axis. The integrity of the brain blood barrier (BBB) and intestinal epithelial barrier (IEB) is also compromised by this inflammation. By emphasizing the central role of NLRP3 inflammasome activation in depression and its far-reaching implications, we go over each area with potential modulating mechanisms within the inflammasome pathway in hopes of finding new targets for more effective management of this debilitating condition.

Copper and cuproptosis: new therapeutic approaches for Alzheimer's disease

Copper (Cu) plays a crucial role as a trace element in various physiological processes in humans. Nonetheless, free copper ions accumulate in the brain over time, resulting in a range of pathological changes. Compelling evidence indicates that excessive free copper deposition contributes to cognitive decline in individuals with Alzheimer's disease (AD). Free copper levels in the serum and brain of AD patients are notably elevated, leading to reduced antioxidant defenses and mitochondrial dysfunction. Moreover, free copper accumulation triggers a specific form of cell death, namely copper-dependent cell death (cuproptosis). This article aimed to review the correlation between copper dysregulation and the pathogenesis of AD, along with the primary pathways regulating copper homoeostasis and copper-induced death in AD. Additionally, the efficacy and safety of natural and synthetic agents, including copper chelators, lipid peroxidation inhibitors, and antioxidants, were examined. These treatments can restore copper equilibrium and prevent copper-induced cell death in AD cases. Another aim of this review was to highlight the significance of copper dysregulation and promote the development of pharmaceutical interventions to address it.

NLRP3 inhibitors: Unleashing their therapeutic potential against inflammatory diseases

The NOD-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasome has been linked to the release of pro-inflammatory cytokines and is essential for innate defence against infection and danger signals. These secreted cytokines improve the inflammatory response caused by tissue damage and associated inflammation. Consequently, the development of NLRP3 inflammasome inhibitors are viable option for the treatment of diverse inflammatory disorders. The significant anti-inflammatory effects of the NLRP3 inhibitors have severe side effects. Hence, the application of NLRP3 inhibitors against inflammatory disease has not yet been understood and most of the developed inhibitors are unsuccessful in clinical trials. The processes behind the NLRP3 complex, priming, and activation are the main emphasis of this review, which also covers therapeutical inhibitors of the NLRP3 inflammasome and potential therapeutic strategies for directing the NLRP3 inflammasome towards clinical development.

Dimethyl fumarate attenuates cholestatic liver injury by activating the NRF2 and FXR pathways and suppressing NLRP3/GSDMD signaling in mice

The progression of cholestasis is characterized by excessive accumulation of bile acids (BAs) in the liver, which leads to oxidative stress (OS), inflammation and liver injury. There are currently limited treatments for cholestasis. Therefore, appropriate drugs for cholestasis treatment need to be developed. Dimethyl fumarate (DMF) has been widely used in the treatment of various diseases and exerts antioxidant and anti-inflammatory effects, but its effect on cholestatic liver disease remains unclarified. We fed mice 3,5-diethoxycarbonyl-1,4-dihydrocollidine or cholic acid to induce cholestatic liver injury and treated these mice with DMF to evaluate its protective ability. Alanine aminotransferase, aspartate aminotransferase, and total liver BAs were assessed as indicators of liver function. The levels of OS, liver inflammation, transporters and metabolic enzymes were also measured. DMF markedly altered the relative ALT and AST levels and enhanced the liver antioxidant capacity. DMF regulated the MST/NRF2 signaling pathway to protect against OS and reduced liver inflammation through the NLRP3/GSDMD signaling pathway. DMF also regulated the levels of BA transporters by promoting FXR protein expression. These findings provide new strategies for the treatment of cholestatic liver disorders.

Lipocalin-2 promotes adipose-macrophage interactions to shape peripheral and central inflammatory responses in experimental autoimmune encephalomyelitis

OBJECTIVE

Accumulating evidence suggests that dysfunctional adipose tissue (AT) plays a major role in the risk of developing multiple sclerosis (MS), the most common immune-mediated and demyelinating disease of the central nervous system. However, the contribution of adipose tissue to the etiology and progression of MS is still obscure. This study aimed at deciphering the responses of AT in experimental autoimmune encephalomyelitis (EAE), the best characterized animal model of MS.

RESULTS AND METHODS

We observed a significant AT loss in EAE mice at the onset of disease, with a significant infiltration of M1-like macrophages and fibrosis in the AT, resembling a cachectic phenotype. Through an integrative and multilayered approach, we identified lipocalin2 (LCN2) as the key molecule released by dysfunctional adipocytes through redox-dependent mechanism. Adipose-derived LCN2 shapes the pro-inflammatory macrophage phenotype, and the genetic deficiency of LCN2 specifically in AT reduced weight loss as well as inflammatory macrophage infiltration in spinal cord in EAE mice. Mature adipocytes downregulating LCN2 reduced lipolytic response to inflammatory stimuli (e.g. TNFα) through an ATGL-mediated mechanism.

CONCLUSIONS

Overall data highlighted a role LCN2 in exacerbating inflammatory phenotype in EAE model, suggesting a pathogenic role of dysfunctional AT in MS.

Novel Heme Oxygenase-1 Inducers Palliate Inflammatory Pain and Emotional Disorders by Regulating NLRP3 Inflammasome and Activating the Antioxidant Pathway

Chronic pain caused by persistent inflammation is current in multiple diseases and has a strong negative impact on society. It is commonly associated with several mental illnesses, which can exert a negative influence on pain perception, and needs to be eradicated. Nevertheless, actual therapies are not sufficiently safe and effective. Recent reports demonstrate that the induction of heme oxygenase-1 (HO-1) enzyme produces analgesic effects in animals with osteoarthritis pain and reverses the grip strength loss caused by sciatic nerve crush. In this research, we evaluated the potential use of three new HO-1 inducers, 1m, 1a, and 1b, as well as dimethyl fumarate (DMF), for treating persistent inflammatory pain induced by the subplantar injection of complete Freud's adjuvant and the functional deficits and emotional sickness associated. The modulator role of these treatments on the inflammatory and antioxidant pathways were also assessed. Our findings revealed that repeated treatment, for four days, with 1m, 1a, 1b, or DMF inhibited inflammatory pain, reversed grip strength deficits, and reversed the linked anxious- and depressive-like behaviors, with 1m being the most effective. These treatments also suppressed the up-regulation of the inflammasome NLRP3 and activated the expression of the Nrf2 transcription factor and the HO-1 and superoxide dismutase 1 enzymes in the paw and/or amygdala, thus revealing the anti-inflammatory and antioxidant capacity of these compounds during inflammatory pain. Results suggest the use of 1m, 1a, 1b, and DMF, particularly 1m, as promising therapies for inflammatory pain and the accompanying functional disabilities and emotional diseases.

Maslinic acid alleviates LPS-induced mice mastitis by inhibiting inflammatory response, maintaining the integrity of the blood-milk barrier and regulating intestinal flora

Mastitis occurs frequently in breastfeeding women and not only affects the women's health but also hinders breastfeeding. Maslinic acid is a type of pentacyclic triterpenoid widely found in olives that has good anti-inflammatory activity. This study aims to discuss the protective function of maslinic acid against mastitis and its underlying mechanism. For this, mice models of mastitis were established using lipopolysaccharide (LPS). The results revealed that maslinic acid reduced the pathological lesions in the mammary gland. In addition, it reduced the generation of pro-inflammatory factors and enzymes (IL-6, IL-1β, TNF-α, iNOS, and COX2) in both mice mammary tissue and mammary epithelial cells. The high-throughput 16S rDNA sequencing of intestinal flora showed that in mice with mastitis, maslinic acid treatment altered β-diversity and regulated microbial structure by increasing the abundance of probiotics such as Enterobacteriaceae and downregulating harmful bacteria such as Streptococcaceae. In addition, maslinic acid protected the blood-milk barrier by maintaining tight-junction protein expression. Furthermore, maslinic acid downregulated mammary inflammation by inhibiting the activation of NLRP3 inflammasome, AKT/NF-κB, and MAPK signaling pathways. Thus, in a mice model of LPS-induced mastitis, maslinic acid can inhibit the inflammatory response, protect the blood-milk barrier, and regulate the constitution of intestinal flora.

Phoenix dactylifera (Ajwa Dates) Alleviate LPS-Induced Sickness Behaviour in Rats by Attenuating Proinflammatory Cytokines and Oxidative Stress in the Brain

Traditional medicine claims that various components of the Phoenix dactylifera (date plant) can be used to treat memory loss, fever, inflammation, loss of consciousness, and nerve disorders. The present study aims to evaluate the effectiveness of Phoenix dactylifera fruit extracts (PDF) against rat sickness behaviour caused by lipopolysaccharide (LPS) by assessing behavioural and biochemical parameters. PDF was prepared by extracting dry fruits of P. dactylifera with a methanol:water (4:1, v/v) mixture. The PDF was evaluated for phenolic and flavonoid content and HPLC analysis of quercetin estimation. Adult Wistar rats were treated with LPS, PDF + LPS and dexamethasone + LPS. Water and food intake, behavioural tests such as locomotor activity, tail suspension and forced swim tests were conducted. Furthermore, alanine transaminase (ALT) and aspartate transaminase (AST) were estimated in plasma and malondialdehyde (MDA), reduced glutathione (GSH), nitrite, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), were estimated in the brain. PDF ameliorated LPS-induced sickness behaviour by reducing MDA, nitrite, IL-6, and TNF-α levels and improving GSH, behavioural alteration, water and food intake in the treated rats. In the plasma of the treated rats, PDF also decreased the levels of ALT and AST. The outcomes demonstrated the efficacy of PDF in reducing the sickness behaviour caused by LPS in rats. The authors believe that this study will provide the groundwork for future research to better understand the underlying mechanisms of action and therapeutic efficacy.

Nrf2 protects against myocardial ischemia-reperfusion injury in diabetic rats by inhibiting Drp1-mediated mitochondrial fission

Mitochondrial dysfunction and oxidative stress are considered to be two main drivers of diabetic myocardial ischemia-reperfusion injury (DM + MIRI). Nuclear factor-erythroid 2-related factor 2 (Nrf2) and Dynamin-related protein 1 (Drp1) play central roles in maintaining mitochondrial homeostasis and regulating oxidative stress, but the effects of the Nrf2-Drp1 pathway on DM-MIRI have not been reported. The aim of this study is to investigate the role of the Nrf2-Drp1 pathway in DM + MIRI rats. A rat model of DM + MIRI and H9c2 cardiomyocyte injury were constructed. The therapeutic effect of Nrf2 was assessed by detecting myocardial infarct size, mitochondrial structure, levels of myocardial injury markers and oxidative stress, apoptosis, and Drp1 expression. The results showed that DM + MIRI rats had increased myocardial infarct size and Drp1 expression in myocardial tissue, accompanied by increased mitochondrial fission and oxidative stress. Interestingly, Nrf2 agonist dimethyl fumarate (DMF) could significantly improve cardiac function, mitochondrial fission, and decrease oxidative stress levels and Drp1 expression after ischemia. However, these effects of DMF would be largely counteracted by the Nrf2 inhibitor ML385. Additionally, Nrf2 overexpression significantly suppressed Drp1 expression, apoptosis, and oxidative stress levels in H9c2 cells. Nrf2 attenuates myocardial ischemia-reperfusion injury in DM rats by reducing Drp1-mediated mitochondrial fission and oxidative stress.

Dimethyl Fumarate and Intestine: From Main Suspect to Potential Ally against Gut Disorders

Dimethyl fumarate (DMF) is a well-characterized molecule that exhibits immuno-modulatory, anti-inflammatory, and antioxidant properties and that is currently approved for the treatment of psoriasis and multiple sclerosis. Due to its Nrf2-dependent and independent mechanisms of action, DMF has a therapeutic potential much broader than expected. In this comprehensive review, we discuss the state-of-the-art and future perspectives regarding the potential repurposing of DMF in the context of chronic inflammatory diseases of the intestine, such as inflammatory bowel disorders (i.e., Crohn's disease and ulcerative colitis) and celiac disease. DMF's mechanisms of action, as well as an exhaustive analysis of the in vitro/in vivo evidence of its beneficial effects on the intestine and the gut microbiota, together with observational studies on multiple sclerosis patients, are here reported. Based on the collected evidence, we highlight the new potential applications of this molecule in the context of inflammatory and immune-mediated intestinal diseases.

Central nervous system demyelinating diseases: glial cells at the hub of pathology

Inflammatory demyelinating diseases (IDDs) are among the main causes of inflammatory and neurodegenerative injury of the central nervous system (CNS) in young adult patients. Of these, multiple sclerosis (MS) is the most frequent and studied, as it affects about a million people in the USA alone. The understanding of the mechanisms underlying their pathology has been advancing, although there are still no highly effective disease-modifying treatments for the progressive symptoms and disability in the late stages of disease. Among these mechanisms, the action of glial cells upon lesion and regeneration has become a prominent research topic, helped not only by the discovery of glia as targets of autoantibodies, but also by their role on CNS homeostasis and neuroinflammation. In the present article, we discuss the participation of glial cells in IDDs, as well as their association with demyelination and synaptic dysfunction throughout the course of the disease and in experimental models, with a focus on MS phenotypes. Further, we discuss the involvement of microglia and astrocytes in lesion formation and organization, remyelination, synaptic induction and pruning through different signaling pathways. We argue that evidence of the several glia-mediated mechanisms in the course of CNS demyelinating diseases supports glial cells as viable targets for therapy development.

Targeting pyroptosis as a preventive and therapeutic approach for stroke

Stroke has caused tremendous social stress worldwide, yet despite decades of research and development of new stroke drugs, most have failed and rt-PA (Recombinant tissue plasminogen activator) is still the accepted treatment for ischemic stroke. the complexity of the stroke mechanism has led to unsatisfactory efficacy of most drugs in clinical trials, indicating that there are still many gaps in our understanding of stroke. Pyroptosis is a programmed cell death (PCD) with inflammatory properties and are thought to be closely associated with stroke. Pyroptosis is regulated by the GSDMD of the gasdermin family, which when cleaved by Caspase-1/Caspase-11 into N-GSDMD with pore-forming activity can bind to the plasma membrane to form small 10-20 nm pores, which would allow the release of inflammatory factors IL-18 and IL-1β before cell rupture, greatly exacerbating the inflammatory response. The pyroptosis occurs mainly in the border zone of cerebral infarction, and glial cells, neuronal cells and brain microvascular endothelial cells (BMECs) all undergo pyroptosis after stroke, which largely exacerbates the breakdown of the blood-brain barrier (BBB) and thus aggravates brain injury. Therefore, pyroptosis may be a good direction for the treatment of stroke. In this review, we focus on the latest mechanisms of action of pyroptosis and the process by which pyroptosis regulates stroke development. We also suggest potential therapeutic stroke drugs that target the pyroptosis pathway, providing additional therapeutic strategies for the clinical management of stroke. The role of pyroptosis after stroke. After stroke, microglia first rush to the damaged area and polarize into M1 and M2 types. Under the influence of various stimuli, microglia undergo pyroptosis, release pro-inflammatory factors, and are converted to the M1 type; astrocytes and neuronal cells also undergo pyroptosis under the stimulation of various pro-inflammatory factors, leading to astrocyte death due to increased osmotic pressure in the membrane, resulting in water absorption and swelling until rupture. BMECs, the main structural component of the BBB, also undergo pyroptosis when stimulated by pro-inflammatory factors released from microglia and astrocytes, leading to the destruction of the structural integrity of the BBB, ultimately causing more severe brain damage. In addition, GSDMD in neutrophils mainly mediate the release of NETs rather than pyroptosis, which also aggravates brain injury. IL-10=interleukin-10; TGF-β = transforming growth factor-β; IL-18=interleukin-18; IL-1β = interleukin-1β; TNF-α = tumor necrosis factor-α; iNOS=induced nitrogen monoxide synthase; MMPs=Matrix metalloproteinases; GSDMD = gasdermin D; BMECs=brain microvascular endothelial cells; BBB = blood-brain barrier.

Targeting immunometabolism against acute lung injury

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are life-threatening conditions triggered by multiple intra- and extra-pulmonary injury factors, characterized by complicated molecular mechanisms and high mortality. Great strides have been made in the field of immunometabolism to clarify the interplay between intracellular metabolism and immune function in the past few years. Emerging evidence unveils the crucial roles of immunometabolism in inflammatory response and ALI. During ALI, both macrophages and lymphocytes undergo robust metabolic reprogramming and discrete epigenetic changes after activated. Apart from providing ATP and biosynthetic precursors, these metabolic cellular reactions and processes in lung also regulate inflammation and immunity.In fact, metabolic reprogramming involving glucose metabolism and fatty acidoxidation (FAO) acts as a double-edged sword in inflammatory response, which not only drives inflammasome activation but also elicits anti-inflammatory response. Additionally, the features and roles of metabolic reprogramming in different immune cells are not exactly the same. Here, we outline the evidence implicating how adverse factors shape immunometabolism in differentiation types of immune cells during ALI and summarize key proteins associated with energy expenditure and metabolic reprogramming. Finally, novel therapeutic targets in metabolic intermediates and enzymes together with current challenges in immunometabolism against ALI were discussed.

Dimethyl fumarate inhibits necroptosis and alleviates systemic inflammatory response syndrome by blocking the RIPK1-RIPK3-MLKL axis

Necroptosis has been implicated in various inflammatory diseases including tumor-necrosis factor-α (TNF-α)-induced systemic inflammatory response syndrome (SIRS). Dimethyl fumarate (DMF), a first-line drug for treating relapsing-remitting multiple sclerosis (RRMS), has been shown to be effective against various inflammatory diseases. However, it is still unclear whether DMF can inhibit necroptosis and confer protection against SIRS. In this study, we found that DMF significantly inhibited necroptotic cell death in macrophages induced by different necroptotic stimulations. Both the autophosphorylation of receptor-interacting serine/threonine kinase 1 (RIPK1) and RIPK3 and the downstream phosphorylation and oligomerization of MLKL were robustly suppressed by DMF. Accompanying the suppression of necroptotic signaling, DMF blocked the mitochondrial reverse electron transport (RET) induced by necroptotic stimulation, which was associated with its electrophilic property. Several well-known anti-RET reagents also markedly inhibited the activation of the RIPK1-RIPK3-MLKL axis accompanied by decreased necrotic cell death, indicating a critical role of RET in necroptotic signaling. DMF and other anti-RET reagents suppressed the ubiquitination of RIPK1 and RIPK3, and they attenuated the formation of necrosome. Moreover, oral administration of DMF significantly alleviated the severity of TNF-α-induced SIRS in mice. Consistent with this, DMF mitigated TNF-α-induced cecal, uterine, and lung damage accompanied by diminished RIPK3-MLKL signaling. Collectively, DMF represents a new necroptosis inhibitor that suppresses the RIPK1-RIPK3-MLKL axis through blocking mitochondrial RET. Our study highlights DMF's potential therapeutic applications for treating SIRS-associated diseases.