FPS-ZM1 inhibits LPS-induced microglial inflammation by suppressing JAK/STAT signaling pathway

Vortioxetine attenuates rotenone-induced enteric neuroinflammation via modulation of the TLR2/S100B/RAGE signaling pathway in a rat model of Parkinson's disease

Emerging evidence suggests that gastrointestinal dysfunction and enteric nervous system pathology play a critical role in the early stages of Parkinson's disease. Considering the bidirectional relationship between gastrointestinal symptoms and mood disorders, this study aimed to elucidate the effects and possible mechanisms of action of vortioxetine, a serotonergic antidepressant, on the pathophysiological changes induced by rotenone in the enteroglial cells. α-synuclein, phosphorylated α-synuclein, TLR2, S100B and RAGE expression were detected in duodenal tissues of rats administered rotenone (2 mg/kg/day, s.c.) and/or vortioxetine (10 mg/kg/day, s.c.) for 28 days. For the mechanism of action studies, rat-derived enteroglial cells were treated with rotenone (10 μM) and/or vortioxetine (5 μM or 1 μM) for 24 h. The effects of vortioxetine were evaluated in the presence of the TLR2 antagonist C29, RAGE antagonist FPS-ZM1 and the S100B inhibitor pentamidine. TLR2, S100B, RAGE, and NFκB mRNA levels and proinflammatory cytokines via RT-qPCR and ELISA. Our results demonstrate that rotenone treatment significantly increased α-synuclein, pS129-α-synuclein, TLR2, and S100B expression while reducing RAGE levels, indicating marked enteric pathology. Vortioxetine administration attenuated these effects, reducing α-synuclein accumulation and proinflammatory markers. In vitro, rotenone impaired glial responses, decreasing S100B, RAGE, and NFκB markers, while vortioxetine improved these responses, promoting resynthesis of inflammatory molecules. Notably, S100B, NFκB, and cytokine levels (TNF-α, IL-1β, IL-6) were affected by C29, FPS-ZM1, and pentamidine pretreatments. Thus, vortioxetine is thought to have beneficial effects on rotenone-induced pathological changes in EGCs, and some of these effects are thought to be mediated by the TLR2/S100B/RAGE pathway.

Pentadecyl®, an odd-chain-rich triglyceride mixture derived from Aurantiochytrium oil, attenuates lipopolysaccharide-induced inflammatory cytokine production in BV-2 microglial cells

BACKGROUND AND AIM

Microglia are the primary immune cells of the central nervous system that play pivotal roles in health and disease. Abnormally activated microglia secrete proinflammatory factors and play essential roles in neurodegenerative disease progression. This study investigated the potential effects of Pentadecyl, rich in odd-numbered fatty acids, such as pentadecanoic acid, isolated from Aurantiochytrium limacinum, on the lipopolysaccharide (LPS)-induced immune response of BV-2 microglial cells.

EXPERIMENTAL PROCEDURE

Cell viability was detected using MTT and LIVE/DEAD assays. mRNA and protein levels of inflammatory cytokines and signaling factors were assessed using real-time PCR and western blotting, respectively.

RESULTS AND CONCLUSION

Pentadecyl did not affect MTT-reducing activity or the number of dead cells stained with ethidium homodimer-1. Pentadecyl selectively mitigated the LPS-induced overproduction of pro-inflammatory cytokines, including interleukin (IL)-6 and IL-1β, at the transcriptional and protein levels, whereas tumor necrosis factor-alpha (TNF-α) expression remained unchanged. Western blot analysis showed that Pentadecyl downregulated the LPS-induced increase in the phosphorylation of signal transducer and activator of transcription 3 (STAT3) but did not affect the phosphorylation of p65, a component of nuclear factor-kappa B, or p38 and c-Jun N-terminal kinase, both of which are mitogen-activated protein kinases. Similar to Pentadecyl, Stattic, a representative STAT3 inhibitor, preferentially suppressed the LPS-induced upregulation of IL-6 and IL-1β mRNA expression, whereas its inhibitory effect on TNF-α expression was relatively modest. These results indicate that Pentadecyl suppresses LPS-induced pro-inflammatory cytokine production without affecting cell survival by regulating the STAT3 signaling pathway in BV-2 cells.

S100A9/RAGE pathway regulation of mitophagy and the effect of JianPi LiShi YangGan formula in acute-on-chronic liver failure

ETHNOPHARMACOLOGICAL RELEVANCE

Mitophagy regulates cellular homeostasis and liver inflammation; however, it is inhibited in acute-on-chronic liver failure (ACLF), which drives disease progression. The JianPi LiShi YangGan formula (YGF) has the potential to improve inflammatory responses and reduce mortality in patients with ACLF. However, the precise mechanisms underlying these effects remain unknown.

AIM OF THE STUDY

We investigated the role of S100A9/RAGE signaling in mitophagy and the protective effects of traditional Chinese medicinal compounds on ACLF.

MATERIALS AND METHODS

An ACLF mouse model was established using carbon tetrachloride, lipopolysaccharide, and d-galactose. Hematoxylin and eosin staining and enzyme-linked immunosorbent assay were employed to evaluate the hepatoprotective effect of YGF in ACLF mice. Mitochondrial damage was assessed using transmission electron microscopy. Protein levels of mitophagy-related indicators were assessed through immunohistochemistry and western blotting, and immunofluorescence staining was performed to observe Lamp2 and COX-IV co-localization.

RESULTS

The hepatocytes of ACLF mice contained damaged mitochondria, decreased mitophagy-related protein (Pink1, Parkin, and LC3B) expression and activated S100A9/RAGE signaling. Inhibiting S100A9 or RAGE improved liver injury in ACLF mice and enhanced Lamp2-COX-IV co-localization. In alpha mouse liver 12 (AML12) cells overexpressing RAGE, recombinant S100A9 protein inhibited mitophagy induced by 3-chlorocarbonyl benzoyl chloride. YGF reduced mitochondrial damage, increased Pink1, Parkin, and LC3B levels, and enhanced mitophagy while inhibiting S100A9/RAGE activation in the hepatocytes of ACLF mice.

CONCLUSIONS

This study found that S100A9/RAGE pathway activation impairs mitophagy, and YGF alleviates liver injury by downregulating S100A9 and RAGE signaling, which may be a novel therapeutic strategy for ACLF.

Indole-3-Propionic Acid Attenuates Neuroinflammation and Cognitive Deficits by Inhibiting the RAGE-JAK2-STAT3 Signaling Pathway

Cognitive disorders such as Alzheimer's disease (AD) are highly prevalent and place heavy burdens on society. Neuroinflammation is a driver of cognitive impairment, with no effective drugs. Indole 3-propionic acid (IPA) is a tryptophan metabolite mainly produced byClostridium sporogenes, which exhibits multiple functions, including antioxidant, anti-inflammatory, antiaging, and neuroprotective properties. However, the restorative effects and molecular mechanisms of IPA in cognitive impairment remain to be investigated. In this study, we found that IPA reduced LPS-induced apoptosis and oxidative damage in HT22 cells and decreased LPS-induced inflammation in BV2 cells. Besides, IPA promoted neurogenesis, inhibited glial cell activation, maintained the integrity of the BBB and intestinal barrier, and remodeled the gut microbiota, thereby alleviating memory impairment in LPS-induced cognitively impaired mice. At the mechanistic level, IPA inhibited the RAGE-JAK2-STAT3 signaling pathway and thus ameliorated neuroinflammation. Interestingly, Colivelin TFA, an activator of JAK2-STAT3 signaling, partially reversed the neurorestorative effects of IPA. In conclusion, IPA ameliorates neuroinflammation and cognitive deficits via the inhibition of the RAGE-JAK2-STAT3 signaling pathway. Thus, IPA may be a potential drug for the treatment of cognitive disorders.

Synthesis of dolutegravir derivatives modified by 1,2,3-triazole structure and their anti-inflammatory activity in LPS-induced BV2 cells

Given the promising anti-inflammatory activity of the HIV integrase inhibitor dolutegravir and the widespread use of the 1,2,3-triazole structure in anti-inflammatory drug development, this study aimed to enhance dolutegravir's efficacy by introducing a 1,2,3-triazole group. As a result, four series of dolutegravir derivatives were synthesized. Screening these derivatives for anti-inflammatory activity in microglial cells revealed that compound 6k demonstrated the most potent anti-inflammatory effect without significant cytotoxicity. Specifically, 6k significantly reduced the transcription levels of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α in lipopolysaccharide (LPS)-induced BV-2 microglial cells. Additionally, 6k decreased the LPS-induced overproduction of inflammatory mediators such as nitric oxide (NO), IL-6, and TNF-α. Further investigation into the upstream inflammatory enzymes iNOS and COX-2 showed that 6k markedly reduced their transcription and protein levels. To elucidate the mechanism underlying the anti-inflammatory effects of dolutegravir derivatives, it was found that compound 6k modulates microglial inflammation by inhibiting the phosphorylation and nuclear translocation of signal transducer and activator of transcription 1/3 (STAT1/3). Moreover, acute toxicity testing in mice indicated that compound 6k exhibited low toxicity, suggesting its potential as a lead compound for the treatment of neuroinflammation.

Exogenous L-fucose attenuates depression induced by chronic unpredictable stress: Implicating core fucosylation has an antidepressant potential

Core fucosylation is one of the most essential modifications of the N-glycans, catalyzed by α1,6-fucosyltransferase (Fut8), which transfers fucose from guanosine 5'-diphosphate (GDP)-fucose to the innermost N-acetylglucosamine residue of N-glycans in an α1-6 linkage. Our previous studies demonstrated that lipopolysaccharide (LPS) can induce a more robust neuroinflammatory response in Fut8 homozygous knockout (KO) (Fut8-/-) and heterozygous KO (Fut8+/-) mice contrasted to the wild-type (Fut8+/+) mice. Exogenous administration of L-fucose suppressed LPS-induced neuroinflammation. Numerous studies indicate that neuroinflammation plays a vital role in the development of depression. Here, we investigated whether core fucosylation regulates depression induced by chronic unpredictable stress (CUS), a well-established model for depression. Our results showed that Fut8+/- mice exhibited depressive-like behaviors and increased neuroinflammation earlier than Fut8+/+ mice. Administration of L-fucose significantly reduced CUS-induced depressive-like behaviors and pro-inflammatory cytokine levels in Fut8+/- mice. The L-fucose treatment produced antidepressant effects by attenuating the complex formation between gp130 and the interleukin-6 (IL-6) receptor and the JAK2/STAT3 signaling pathway. Notably, L-fucose treatment increased dendritic spine density and postsynaptic density protein 95 (PSD-95) expression, which were suppressed in CUS-induced depression. Furthermore, the effects of L-fucose on the CUS-induced depression were also observed in Fut8+/+ mice. Our results clearly demonstrate that L-fucose ameliorates neuroinflammation and synaptic defects in CUS-induced depression, implicating that core fucosylation has significant anti-neuroinflammatory activity and an antidepressant potential.

Endothelial GSDMD underlies LPS-induced systemic vascular injury and lethality

Endothelial injury destroys endothelial barrier integrity, triggering organ dysfunction and ultimately resulting in sepsis-related death. Considerable attention has been focused on identifying effective targets for inhibiting damage to endothelial cells to treat endotoxemia-induced septic shock. Global gasdermin D (Gsdmd) deletion reportedly prevents death caused by endotoxemia. However, the role of endothelial GSDMD in endothelial injury and lethality in lipopolysaccharide-induced (LPS-induced) endotoxemia and the underlying regulatory mechanisms are unknown. Here, we show that LPS increases endothelial GSDMD level in aortas and lung microvessels. We demonstrated that endothelial Gsdmd deficiency, but not myeloid cell Gsdmd deletion, protects against endothelial injury and death in mice with endotoxemia or sepsis. In vivo experiments suggested that hepatocyte GSDMD mediated the release of high-mobility group box 1, which subsequently binds to the receptor for advanced glycation end products in endothelial cells to cause systemic vascular injury, ultimately resulting in acute lung injury and lethality in shock driven by endotoxemia or sepsis. Additionally, inhibiting endothelial GSDMD activation via a polypeptide inhibitor alleviated endothelial damage and improved survival in a mouse model of endotoxemia or sepsis. These data suggest that endothelial GSDMD is a viable pharmaceutical target for treating endotoxemia and endotoxemia-induced sepsis.

CircKat6b Mediates the Antidepressant Effect of Esketamine by Regulating Astrocyte Function

The abundant expression of circular RNAs (circRNAs) in the central nervous system and their contribution to the pathogenesis of depression suggest that circRNAs are promising therapeutic targets for depression. This study explored the role and mechanism of circKat6b in esketamine's antidepressant effect. We found that intravenous administration of esketamine (5 mg/kg) treatment decreased the circKat6b expression in the astrocytes of hippocampus induced by a chronic unpredictable mild stress (CUMS) mouse model, while the overexpression of circKat6b in the hippocampus significantly attenuated the antidepressant effects of esketamine in depressed mice. RNA-sequencing, RT-PCR, and western blot experiments showed that the stat1 and p-stat1 expression were significantly upregulated in mouse astrocytes overexpressing circKat6b. In the CUMS mouse model, overexpression of circKat6b in the hippocampus significantly reversed the downregulation of p-stat1 protein expression caused by esketamine. Our findings demonstrated that a novel mechanism of the antidepressant like effect of esketamine may be achieved by reducing the expression of circKat6b in the astrocyte of the hippocampus of depressed mice.

Design, synthesis, and anti-inflammatory activity of 2H-1,4-benzoxazin-3(4H)-one derivatives modified with 1,2,3-triazole in LPS-induced BV-2 cells

Given the potent anti-inflammatory properties of the 1,2,3-triazole structure and the wide use of 2H-1,4-benzoxazin-3(4H)-one in developing treatments for neurodegenerative diseases, a series of 2H-1,4-benzoxazin-3(4H)-one derivatives were synthesized by introducing a 1,2,3-triazole moiety. Screening for anti-inflammatory activity in microglial cells revealed that compounds e2, e16, and e20 exhibited the most promising effects without significant cytotoxicity. These compounds effectively reduced LPS-induced NO production and significantly decreased the transcription levels of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α. Furthermore, they downregulated the transcription and protein levels of the inflammation-related enzymes iNOS and COX-2 in response to LPS stimulation. To further investigate the anti-inflammatory mechanisms of these derivatives in microglia, the intracellular ROS levels and the activation of the Nrf2-HO-1 signaling pathway were analyzed. The results indicated that the 2H-1,4-benzoxazin-3(4H)-one derivatives significantly activated the Nrf2-HO-1 pathway, reduced LPS-induced ROS production, and alleviated microglial inflammation. Molecular docking studies suggested that compounds e2, e16, and e20 could interact with Nrf2-related binding sites, preventing its degradation by Keap1. Additionally, acute toxicity tests in mice demonstrated that compound e16 exhibited favorable safety.

Falcarindiol improves functional recovery and alleviates neuroinflammation after spinal cord injury by inhibiting STAT/MAPK signaling pathways

Spinal cord injury (SCI) is a devastating trauma in the central nervous system (CNS), leading to motor and sensory impairment. Neuroinflammation is one of the critical contributors to the progression of secondary injury. Falcarindiol has been reported to efficaciously mitigate lipopolysaccharide (LPS)-mediated inflammation in RAW 264.7 cells. The role of falcarindiol in SCI recovery remains unclear. In this present study, traumatic SCI mice models and LPS-stimulated murine microglia cell line (BV2 cells) were performed to explore the pharmacological effects and the underlying mechanisms of falcarindiol in improving SCI repair with detection of motor function recovery, morphological changes, numbers of survival neurons and protein expression levels of inflammation or apoptosis-related proteins. Our study found that falcarindiol intervention could promote motor function recovery and reduce spinal cord tissue damage in mice following SCI. Mechanistically, falcarindiol intervention suppressed apoptosis-driven neuronal cell death and mitigated inflammatory reactions following SCI. Additionally, falcarindiol inhibited the activation of signal transducer and activator of transcription (STAT) and mitogen-activated protein kinases (MAPK) signaling pathways in vivo and in vitro. This suppression of STAT and MAPK activation by falcarindiol was reversed by STAT3 agonist Colivelin TFA and MAPK agonist C16-PAF in BV2 cells, respectively. Moreover, the study further demonstrated that the anti-inflammation role of falcarindiol was obstructed by Colivelin TFA but not by C16-PAF in LPS-stimulated BV2 cells, suggesting that falcarindiol may efficaciously ameliorate neuroinflammation through inhibiting the activation of STAT signaling pathway following SCI. Collectively, our study indicates that falcarindiol may be a novel drug candidate for the treatment and management of SCI.

ABBV-744 alleviates LPS-induced neuroinflammation via regulation of BATF2-IRF4-STAT1/3/5 axis

Suppression of neuroinflammation using small molecule compounds targeting the key pathways in microglial inflammation has attracted great interest. Recently, increasing attention has been gained to the role of the second bromodomain (BD2) of the bromodomain and extra-terminal (BET) proteins, while its effect and molecular mechanism on microglial inflammation has not yet been explored. In this study, we evaluated the therapeutic effects of ABBV-744, a BD2 high selective BET inhibitor, on lipopolysaccharide (LPS)-induced microglial inflammation in vitro and in vivo, and explored the key pathways by which ABBV-744 regulated microglia-mediated neuroinflammation. We found that pretreatment of ABBV-744 concentration-dependently inhibited the expression of LPS-induced inflammatory mediators/enzymes including NO, TNF-α, IL-1β, IL-6, iNOS, and COX-2 in BV-2 microglial cells. These effects were validated in LPS-treated primary microglial cells. Furthermore, we observed that administration of ABBV-744 significantly alleviated LPS-induced activation of microglia and transcriptional levels of pro-inflammatory factors TNF-α and IL-1β in mouse hippocampus and cortex. RNA-Sequencing (RNA-seq) analysis revealed that ABBV-744 induced 508 differentially expressed genes (DEGs) in LPS-stimulated BV-2 cells, and gene enrichment and gene expression network analysis verified its regulation on activated microglial genes and inflammatory pathways. We demonstrated that pretreatment of ABBV-744 significantly reduced the expression levels of basic leucine zipper ATF-like transcription factor 2 (BATF2) and interferon regulatory factor 4 (IRF4), and suppressed JAK-STAT signaling pathway in LPS-stimulated BV-2 cells and mice, suggesting that the anti-neuroinflammatory effect of ABBV-744 might be associated with regulation of BATF2-IRF4-STAT1/3/5 pathway, which was confirmed by gene knockdown experiments. This study demonstrates the effect of a BD2 high selective BET inhibitor, ABBV-744, against microglial inflammation, and reveals a BATF2-IRF4-STAT1/3/5 pathway in regulation of microglial inflammation, which might provide new clues for discovery of effective therapeutic strategy against neuroinflammation.

Effects and Mechanisms of the Xianhecao-Huanglian Drug Pair on Autophagy-Mediated Intervention in Acute Inflammatory Bowel Disease via the JAK2/STAT3 Pathway

To explore the effects and mechanisms of the Xianhecao-Huanglian drug pair on autophagy-mediated intervention in acute inflammatory bowel disease (IBD) via the JAK2/STAT3 pathway. The study examined the underlying mechanisms of action of Xianhecao (APL) and Huanglian (CR) using a mouse model of dextran sodium sulfate (DSS)-induced acute inflammatory bowel disease (IBD) and in an in vitro model of IBD induced by lipopolysaccharide (LPS). The assessment of the therapeutic efficacy of the Xianhecao-Huanglian drug combination in a mouse model of IBD caused by DSS included the following parameters: Assessment of weight loss or gain. Measurement of the disease activity index (DAI). Assessment of histological damage. Determination of organ index. Measurement of colon length. Ascertain the levels of inflammatory cytokines in the intestinal tissues and serum of mice. Immunohistochemistry (IHC) for the measurement of tight junction protein concentrations in the colon mucosa, including ZO-1, claudin-1, and occludin. Measurement of mucin levels, specifically Mucin 2 (Muc2). Hematoxylin and eosin (HE) staining for the observation of histopathological alterations in colonic tissues. Examining the effect on goblet cells using periodic acid-Schiff (PAS) labeling. Application of Western blot and immunofluorescence techniques for the detection of autophagy-related markers in colonic tissues and proteins associated with the JAK2/STAT3 pathway. A cell inflammation model of IBD was induced through LPS stimulation, and a serum containing the Xianhecao-Huanglian drug pair (referred to as ACHP-DS) was formulated. Cell viability, anti-proinflammatory cytokines, tight junction proteins, mucins, autophagy-related markers, and the JAK2/STAT3 signaling pathway were assessed. The Xianhecao-Huanglian drug pair significantly ameliorated the symptoms and survival quality of acute IBD mice, reducing the disease activity index score, raising MUC2 secretion and tight junction protein expression to improve the integrity of the intestinal barrier, and preserving goblet cell function; thus, protecting the intestines. It effectively restrained triggering the signaling pathway that involves JAK2 and STAT3, leading to the suppression of inflammation and amelioration of colonic inflammation damage. Additionally, it induced autophagy in mouse colonic tissues.The in vitro experiments demonstrated that the Xianhecao-Huanglian drug combination enhanced the viability of LOVO and NCM460 cells when exposed to LPS stimulation. Furthermore, it suppressed the production of inflammatory cytokines such as IL-6, IL-1β, as well as TNF-α, whilst increasing the production of IL-10, ZO-1, along with MUC2. These effects collectively led to the alleviation of inflammation and the restoration of mucosal integrity. The results were consistent with what was shown in the in vivo trial. Moreover, the medication demonstrated effectiveness in reducing JAK2 along with STAT3 phosphorylation levels in the LPS-induced inflammatory model of IBD cells. The intervention with either the Xianhecao-Huanglian drug combination-containing serum or the JAK2/STAT3 pathway inhibitor AG490 reversed the pro-inflammatory effects and increased autophagy levels in the LPS-stimulated cells. The Xianhecao-Huanglian drug combination modulates the JAK2/STAT3 pathway, leading to the induction of autophagy, which serves as an intervention for IBD.

Fisetin Promotes Functional Recovery after Spinal Cord Injury by Inhibiting Microglia/Macrophage M1 Polarization and JAK2/STAT3 Signaling Pathway

Spinal cord injury (SCI) is one of the most serious health problems, with no effective therapy. Recent studies indicate that Fisetin, a natural polyphenolic flavonoid, exhibits multiple functions, such as life-prolonging, antioxidant, antitumor, and neuroprotection. However, the restorative effects of Fisetin on SCI and the underlying mechanism are still unclear. In the present study, we found that Fisetin reduced LPS-induced apoptosis and oxidative damage in PC12 cells and reversed LPS-induced M1 polarization in BV2 cells. Additionally, Fisetin safely and effectively promoted the motor function recovery of SCI mice by attenuating neurological damage and promoting neurogenesis at the lesion. Moreover, Fisetin administration inhibited glial scar formation, modulated microglia/macrophage polarization, and reduced neuroinflammation. Network pharmacology, RNA-seq, and molecular biology revealed that Fisetin inhibited the activation of the JAK2/STAT3 signaling pathway. Notably, Colivelin TFA, an activator of JAK2/STAT3 signaling, attenuated Fis-mediated neuroinflammation inhibition and therapeutic effects on SCI mice. Collectively, Fisetin promotes functional recovery after SCI by inhibiting microglia/macrophage M1 polarization and the JAK2/STAT3 signaling pathway. Thus, Fisetin may be a promising therapeutic drug for the treatment of SCI.

Super-enhancer-driven LIF promotes the mesenchymal transition in glioblastoma by activating ITGB2 signaling feedback in microglia

BACKGROUND

The mesenchymal (MES) subtype of glioblastoma (GBM) is believed to be influenced by both cancer cell-intrinsic alterations and extrinsic cellular interactions, yet the underlying mechanisms remain unexplored.

METHODS

Identification of microglial heterogeneity by bioinformatics analysis. Transwell migration, invasion assays, and tumor models were used to determine gene function and the role of small molecule inhibitors. RNA sequencing, chromatin immunoprecipitation, and dual-luciferase reporter assays were performed to explore the underlying regulatory mechanisms.

RESULTS

We identified the inflammatory microglial subtype of tumor-associated microglia (TAM) and found that its specific gene integrin beta 2 (ITGB2) was highly expressed in TAM of MES GBM tissues. Mechanistically, the activation of ITGB2 in microglia promoted the interaction between the SH2 domain of STAT3 and the cytoplasmic domain of ITGB2, thereby stimulating the JAK1/STAT3/IL-6 signaling feedback to promote the MES transition of GBM cells. Additionally, microglia communicated with GBM cells through the interaction between the receptor ITGB2 on microglia and the ligand ICAM-1 on GBM cells, while an increased secretion of ICAM-1 was induced by the proinflammatory cytokine leukemia inhibitory factor (LIF). Further studies demonstrated that inhibition of cyclin-dependent kinase 7 substantially reduced the recruitment of SNW1 to the super-enhancer of LIF, resulting in transcriptional inhibition of LIF. We identified notoginsenoside R1 as a novel LIF inhibitor that exhibited synergistic effects in combination with temozolomide.

CONCLUSIONS

Our research reveals that the epigenetic-mediated interaction of GBM cells with TAM drives the MES transition of GBM and provides a novel therapeutic avenue for patients with MES GBM.

Increased alpha-synuclein and neuroinflammation in the substantia nigra triggered by systemic inflammation are reversed by targeted inhibition of the receptor for advanced glycation end products (RAGE)

The receptor for advanced glycation end products (RAGE) is a protein of the immunoglobulin superfamily capable of regulating inflammation. Considering the role of this receptor in the initiation and establishment of neuroinflammation, and the limited understanding of the function of RAGE in the maintenance of this condition, this study describes the effects of RAGE inhibition in the brain, through an intranasal treatment with the antagonist FPS-ZM1, in an animal model of chronic neuroinflammation induced by acute intraperitoneal injection of lipopolysaccharide (LPS). Seventy days after LPS administration (2 mg/kg, i.p.), Wistar rats received, intranasally, 1.2 mg of FPS-ZM1 over 14 days. On days 88 and 89, the animals were submitted to the open-field test and were killed on day 90 after the intraperitoneal injection of LPS. Our results indicate that blockade of encephalic RAGE attenuates LPS-induced chronic neuroinflammation in different brain regions. Furthermore, we found that intranasal FPS-ZM1 administration reduced levels of gliosis markers, RAGE ligands, and α-synuclein in the substantia nigra pars compacta. Additionally, the treatment also reversed the increase in S100 calcium-binding protein B (RAGE ligand) in the cerebrospinal fluid and the cognitive-behavioral deficits promoted by LPS-less time spent in the central zone of the open-field arena (more time in the lateral zones), decreased total distance traveled, and increased number of freezing episodes. In summary, our study demonstrates the prominent role of RAGE in the maintenance of a chronic neuroinflammatory state triggered by a single episode of systemic inflammation and also points to possible future RAGE-based therapeutic approaches to treat conditions in which chronic neuroinflammation and increased α-synuclein levels could play a relevant role, such as in Parkinson's disease.

The miR-23b-3p from adipose-derived stem cell exosomes alleviate inflammation in mice experiencing kainic acid-induced epileptic seizures

Epilepsy is a common neurologic disorder. While a good clinical solution is still missing, studies have confirmed that exosomes (Exos) derived from adipose-derived stem cells (ADSCs) had a therapeutic effect on various diseases, including neurological diseases. Therefore, this study aimed to reveal whether ADSC-Exo treatment could improve kainic acid (KA)-induced seizures in epileptic mice. ADSCs and Exos were isolated. Mice were generated with KA-induced epileptic seizures. ELISA was used to detect inflammatory factor expression. Luciferase reporter analysis detection showed a relationship among miR-23b-3p, STAT1, and glyoxylate reductase 1 (GlyR1). ADSC-Exos had a protective effect on KA-induced seizures by inhibiting inflammatory factor expression and the M1 microglia phenotype. The result showed that miR-23b-3p played an important role in the Exo-mediated protective effect in KA-induced seizures in epileptic mice by regulating STAT1 and GlyR1. Luciferase reporter analysis confirmed that miR-23b-3p interacted with the 3'-UTR of STAT1 and GlyR1. The miR-23b-3p inhibited M1 microglia-mediated inflammatory factor expression in microglial cells by regulating STAT1 and GlyR1. The downregulation of miR-23b-3p decreased the protective effect of ADSC-Exos on KA-induced seizures in epileptic mice. The miR-23b-3p from ADSC-Exos alleviated inflammation in mice with KA-induced epileptic seizures.

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.

Immunological dimensions of neuroinflammation and microglial activation: exploring innovative immunomodulatory approaches to mitigate neuroinflammatory progression

The increasing life expectancy has led to a higher incidence of age-related neurodegenerative conditions. Within this framework, neuroinflammation emerges as a significant contributing factor. It involves the activation of microglia and astrocytes, leading to the release of pro-inflammatory cytokines and chemokines and the infiltration of peripheral leukocytes into the central nervous system (CNS). These instances result in neuronal damage and neurodegeneration through activated nucleotide-binding domain and leucine-rich repeat containing (NLR) family pyrin domain containing protein 3 (NLRP3) and nuclear factor kappa B (NF-kB) pathways and decreased nuclear factor erythroid 2-related factor 2 (Nrf2) activity. Due to limited effectiveness regarding the inhibition of neuroinflammatory targets using conventional drugs, there is challenging growth in the search for innovative therapies for alleviating neuroinflammation in CNS diseases or even before their onset. Our results indicate that interventions focusing on Interleukin-Driven Immunomodulation, Chemokine (CXC) Receptor Signaling and Expression, Cold Exposure, and Fibrin-Targeted strategies significantly promise to mitigate neuroinflammatory processes. These approaches demonstrate potential anti-neuroinflammatory effects, addressing conditions such as Multiple Sclerosis, Experimental autoimmune encephalomyelitis, Parkinson's Disease, and Alzheimer's Disease. While the findings are promising, immunomodulatory therapies often face limitations due to Immune-Related Adverse Events. Therefore, the conduction of randomized clinical trials in this matter is mandatory, and will pave the way for a promising future in the development of new medicines with specific therapeutic targets.

Forsythiaside A exhibits anti-migration and anti-inflammation effects in rheumatoid arthritis in vitro model

BACKGROUND

Rheumatoid arthritis (RA) is a kind of systemic autoimmune disease, and the joint inflammation and cartilage destruction are the major features. Some traditional Chinese medicine have been discovered to exhibit regulatory roles in the treatment of RA. Forsythiaside A (FA) as an active ingredient isolated from forsythia suspensa has been discovered to participate into the regulation of some diseases through improving inflammation. However, the regulatory effects of FA on the progression of RA keep indistinct.

METHODS

IL-1β treatment (10 ng/mL) in MH7A cells was built to mimic RA in vitro (cell) model. The cell viability was examined through CCK-8 assay. The cell proliferation was detected through Edu assay. The levels of TNF-α, IL-6, and IL-8 were evaluated through ELISA. The protein expressions were measured through western blot. The cell apoptosis was assessed through flow cytometry. The cell migration and invasion abilities were tested through Transwell assay.

RESULTS

In this study, it was revealed that the cell proliferation was strengthened after IL-1β treatment (p < .001), but this effect was reversed after FA treatment in a dose-increasing manner (p < .05). Furthermore, FA suppressed inflammation in IL-1β-triggered MH7A cells through attenuating the levels of TNF-α, IL-6, and IL-8 (p < .05). The cell apoptosis was lessened after IL-1β treatment (p < .001), but this effect was rescued after FA treatment (p < .05). Besides, the cell migration and invasion abilities were both increased after IL-1β treatment (p < .001), but these changes were offset after FA treatment (p < .05). Eventually, FA retarded the JAK/STAT pathway through reducing p-JAK/JAK and p-STAT/STAT levels (p < .01).

CONCLUSION

Our study manifested that FA exhibited anti-migration and anti-inflammation effects in RA in vitro model (IL-1β-triggered MH7A cells) through regulating the JAK/STAT pathway. This work hinted that FA can be an effective drug for RA treatment.

The Role of JAK/STAT Signaling Pathway and Its Downstream Influencing Factors in the Treatment of Atherosclerosis

Atherosclerosis is now widely considered to be a chronic inflammatory disease, with increasing evidence suggesting that lipid alone is not the main factor contributing to its development. Rather, atherosclerotic plaques contain a significant amount of inflammatory cells, characterized by the accumulation of monocytes and lymphocytes on the vessel wall. This suggests that inflammation may play a crucial role in the occurrence and progression of atherosclerosis. As research deepens, other pathological factors have also been found to influence the development of the disease. The Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway is a recently discovered target of inflammation that has gained attention in recent years. Numerous studies have provided evidence for the causal role of this pathway in atherosclerosis, and its downstream signaling factors play a significant role in this process. This brief review aims to explore the crucial role of the JAK/STAT pathway and its representative downstream signaling factors in the development of atherosclerosis. It provides a new theoretical basis for clinically affecting the development of atherosclerosis by interfering with the JAK/STAT signaling pathway.

Modulating the RAGE-Induced Inflammatory Response: Peptoids as RAGE Antagonists

While the primary pathology of Alzheimer's disease (AD) is defined by brain deposition of amyloid-β (Aβ) plaques and tau neurofibrillary tangles, chronic inflammation has emerged as an important factor in AD etiology. Upregulated cell surface expression of the receptor for advanced glycation end-products (RAGE), a key receptor of innate immune response, is reported in AD. In parallel, RAGE ligands, including Aβ aggregates, HMGB1, and S100B, are elevated in AD brain. Activation of RAGE by these ligands triggers release of inflammatory cytokines and upregulates cell surface RAGE. Despite such observation, there are currently no therapeutics that target RAGE for treatment of AD-associated neuroinflammation. Peptoids, a novel class of potential AD therapeutics, display low toxicity, facile blood-brain barrier permeability, and resistance to proteolytic degradation. In the current study, peptoids were designed to mimic Aβ, a ligand that binds the V-domain of RAGE, and curtail RAGE inflammatory activation. We reveal the nanomolar binding capability of peptoids JPT1 and JPT1a to RAGE and demonstrate their ability to attenuate lipopolysaccharide-induced pro-inflammatory cytokine production as well as upregulation of RAGE cell surface expression. These results support RAGE antagonist peptoid-based mimics as a prospective therapeutic strategy to counter neuroinflammation in AD and other neurodegenerative diseases.

Synthesis and biological evaluation of chromanone-based derivatives as potential anti-neuroinflammatory agents

As a privileged scaffold, chromanone has been extensively introduced in the design of drug leads with diverse pharmacological features, particularly in the area of inflammatory diseases. Herein, the preparation of chromanone-based derivatives (4a-4i) was smoothly achieved, and their structures were characterized using 1H NMR, 13C NMR, and ESI-HRMS spectroscopy techniques. Out of them, analogue 4e exhibited the most potent inhibitory capacity against the NO release and iNOS expression, without apparent cytotoxicity. Our observations showed that 4e could dramatically prevent the translocation of NF-κB from the cytoplasm to nucleus, and decrease the production of proinflammatory cytokines TNF-α, IL-6 and IL-1β in LPS-induced BV-2 cells. Mechanistically, 4e significantly deactivated NF-κB by disturbing TLR4-mediated TAK1/NF-κB and PI3K/Akt signaling cascades. Consistent with the in vitro study, 4e could effectively mitigate the inflammation response of hippocampal tissue in LPS-induced mouse model by inhibiting microglial activation. Collectively, these results revealed 4e as a prospective neuroprotective candidate for the therapy of neuroinflammation-related disorders.

TIPE2 regulates the response of BV2 cells to lipopolysaccharide by the crosstalk between PI3K/AKT signaling and microglia M1/M2 polarization

Tumor necrosis factor (TNF)-α-induced protein 8-like 2 (TIPE2) is a crucial negative regulator of both adaptive and innate immunity, which helps maintain the dynamic balance of the immune system by negatively regulating the signaling of T-cell receptors (TCR) and Toll-like receptors (TLR). In this study, we aimed to investigate the role and molecular mechanism of TIPE2 using a lipopolysaccharide (LPS)-induced inflammatory injury model in BV2 cells. Specifically, we constructed a BV2 cell line of TIPE2-overexpression or TIPE2-knockdown via lentiviral transfection. Our results demonstrated that overexpression of TIPE2 downregulated the expression of pro-inflammatory cytokines IL-1β and IL-6, which was reversed by knockdown of TIPE2 in the inflammation model of BV2 cells. In addition, overexpression of TIPE2 resulted in the conversion of BV2 cells to the M2 phenotype, while the knockdown of TIPE2 promoted the transformation of BV2 cells to the M1 phenotype. Notably, our co-culture experiments with neuronal cells SH-SY5Y showed that the overexpression of TIPE2 in inflammation-injured BV2 cells exhibited a protective effect on the neuronal cells. Finally, western blot analysis demonstrated that TIPE2 significantly reduced the expression of p-PI3K, p-AKT, p-p65, and p-IκBα in LPS treated BV2 cells, and inhibited the activation of NF-κB through the dephosphorylation of PI3K/AKT. These results suggest that TIPE2 plays an important role in mediating neuroinflammatory responses and may be involved in neuroprotection by modulating the phenotypic changes of BV2 cells and regulating the pro-inflammatory responses through the PI3K/AKT and NF-κB signaling pathways. In conclusion, our study provides new insights into the crucial role of TIPE2 in regulating neuroinflammatory responses and highlights its potential as a therapeutic target for neuroprotection.

Linderone Isolated from Lindera erythrocarpa Exerts Antioxidant and Anti-Neuroinflammatory Effects via NF-κB and Nrf2 Pathways in BV2 and HT22 Cells

Linderone is a major compound in Lindera erythrocarpa and exhibits anti-inflammatory effects in BV2 cells. This study investigated the neuroprotective effects and mechanisms of linderone action in BV2 and HT22 cells. Linderone suppressed lipopolysaccharide (LPS)-induced inducible nitric oxide synthase, cyclooxygenase-2, and pro-inflammatory cytokines (e.g., tumor necrosis factor alpha, interleukin-6, and prostaglandin E-2) in BV2 cells. Linderone treatment also inhibited the LPS-induced activation of p65 nuclear factor-kappa B, protecting against oxidative stress in glutamate-stimulated HT22 cells. Furthermore, linderone activated the translocation of nuclear factor E2-related factor 2 and induces the expression of heme oxygenase-1. These findings provided a mechanistic explanation of the antioxidant and anti-neuroinflammatory effects of linderone. In conclusion, our study demonstrated the therapeutic potential of linderone in neuronal diseases.

Alpinetin inhibits neuroinflammation and neuronal apoptosis via targeting the JAK2/STAT3 signaling pathway in spinal cord injury

BACKGROUND

A growing body of research shows that drug monomers from traditional Chinese herbal medicines have antineuroinflammatory and neuroprotective effects that can significantly improve the recovery of motor function after spinal cord injury (SCI). Here, we explore the role and molecular mechanisms of Alpinetin on activating microglia-mediated neuroinflammation and neuronal apoptosis after SCI.

METHODS

Stimulation of microglia with lipopolysaccharide (LPS) to simulate neuroinflammation models in vitro, the effect of Alpinetin on the release of pro-inflammatory mediators in LPS-induced microglia and its mechanism were detected. In addition, a co-culture system of microglia and neuronal cells was constructed to assess the effect of Alpinetin on activating microglia-mediated neuronal apoptosis. Finally, rat spinal cord injury models were used to study the effects on inflammation, neuronal apoptosis, axonal regeneration, and motor function recovery in Alpinetin.

RESULTS

Alpinetin inhibits microglia-mediated neuroinflammation and activity of the JAK2/STAT3 pathway. Alpinetin can also reverse activated microglia-mediated reactive oxygen species (ROS) production and decrease of mitochondrial membrane potential (MMP) in PC12 neuronal cells. In addition, in vivo Alpinetin significantly inhibits the inflammatory response and neuronal apoptosis, improves axonal regeneration, and recovery of motor function.

CONCLUSION

Alpinetin can be used to treat neurodegenerative diseases and is a novel drug candidate for the treatment of microglia-mediated neuroinflammation.