Aprepitant attenuates NLRC4-dependent neuronal pyroptosis via NK1R/PKCδ pathway in a mouse model of intracerebral hemorrhage

Egr1 promotes Nlrc4-dependent neuronal pyroptosis through phlda1 in an in-vitro model of intracerebral hemorrhage

Intracerebral hemorrhage (ICH) is a fatal brain injury, but the current treatments for it are inadequate to reduce the severity of secondary brain injury. Our study aims to explore the molecular mechanism of Egr1 and Phlda1 in regulating hemin-induced neuronal pyroptosis, and hope to provide novel therapeutic targets for ICH treatment. Mouse hippocampal neuron cells treated with hemin were used to simulate an in-vitro ICH model. Using qRT-PCR and western blot to evaluate mRNA and protein concentrations. MTT assay was utilized to assess cell viability. LDH levels were determined by lactate Dehydrogenase Activity Assay Kit. IL-1β and IL-18 levels were examined by ELISA. The interaction of Egr1 and Phlda1 promoter was evaluated using chromatin immunoprecipitation and dual-luciferase reporter assays. Egr1 and Phlda1 were both upregulated in HT22 cells following hemin treatment. Hemin treatment caused a significant reduction in HT22 cell viability, an increase in Nlrc4 and HT22 cell pyroptosis, and heightened inflammation. However, knocking down Egr1 neutralized hemin-induced effects on HT22 cells. Egr1 bound to the promoter of Phlda1 and transcriptionally activated Phlda1. Silencing Phlda1 significantly reduced Nlrc4-dependent neuronal pyroptosis. Conversely, overexpressing Phlda1 mitigated the inhibitory effects of Egr1 knockdown on Nlrc4 and neuronal pyroptosis during ICH. Egr1 enhanced neuronal pyroptosis mediated by Nlrc4 under ICH via transcriptionally activating Phlda1.

Yi-Qi-Huo-Xue decoction alleviates intracerebral hemorrhage injury through inhibiting neuronal autophagy of ipsilateral cortex via BDNF/TrkB pathway

BACKGROUND

Yi-Qi-Huo-Xue Decoction (YQHXD), a traditional Chinese medicine formula, has demonstrated efficacy in the clinical treatment of intracerebral hemorrhage (ICH) for over a decade. Nevertheless, the precise pharmacotherapeutic compounds of YQHXD capable of penetrating into cerebral tissue and the pharmacological underpinnings of YQHXD remain ambiguous.

METHODS

The active components of YQHXD in rat brains was analyzed by ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. The potential targets, pathways and biological progresses of YQHXD ameliorating ICH induced injury was predicted by network pharmacology. Moreover, collagenase-induced ICH rat model, primary cortex neurons exposed to hemin and molecular docking were applied to validate the molecular mechanisms of YQHXD.

RESULTS

Eleven active components of YQHXD were identified within the brains. Employing the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, our investigation concentrated on the roles of autophagy and the BDNF/TrkB signaling pathway in the pharmacological context. The pharmacological results revealed that YQHXD alleviated neurological dysfunction, brain water content, brain swelling, and pathological injury caused by ICH. Meanwhile, YQHXD inhibited autophagy influx and autophagosome in vivo, and regulated cortex neuronal autophagy and TrkB/BDNF pathway both in vivo and in vitro. Subsequently, N-acetyl serotonin (NAS), a selective TrkB agonist, was employed to corroborate the significance of the BDNF/TrkB pathway in this process. The combination of NAS and YQHXD did not further enhance the protective efficacy of YQHXD in ICH rats. Additionally, outcomes of molecular docking analysis revealed that nine compounds of YQHXD exhibited potential regulatory effects on TrkB.

CONCLUSIONS

Ipsilateral neuronal autophagy and BDNF/TrkB pathway were activated 72 h after ICH. YQHXD effectively resisted injury induced by ICH, which was related with suppression of ipsilateral neuronal autophagy via BDNF/TrkB pathway. This study provides novel insights into the therapeutic mechanisms of traditional Chinese medicine in the context of ICH treatment.

Peroxiredoxin II exerts neuroprotective effects by inhibiting endoplasmic reticulum stress and oxidative stress-induced neuronal pyroptosis

BACKGROUND

Intracerebral hemorrhage (ICH) is a critical neurological condition with few treatment options, where secondary immune responses and specific cell death forms, like pyroptosis, worsen brain damage. Pyroptosis involves gasdermin-mediated membrane pores, increasing inflammation and neural harm, with the NLRP3/Caspase-1/GSDMD pathway being central to this process. Peroxiredoxin II (Prx II), recognized for its mitochondrial protection and reactive oxygen species (ROS) scavenging abilities, appears as a promising neuronal pyroptosis modulator. However, its exact role and action mechanisms need clearer definition. This research aims to explore Prx II impact on neuronal pyroptosis and elucidate its mechanisms, especially regarding endoplasmic reticulum (ER) stress and oxidative stress-induced neuronal damage modulation.

METHODS AND RESULTS

Utilizing MTT assays, Microscopy, Hoechst/PI staining, Western blotting, and immunofluorescence, we found Prx II effectively reduces LPS/ATP-induced pyroptosis and neuroinflammation in HT22 hippocampal neuronal cells. Our results indicate Prx II's neuroprotective actions are mediated through PI3K/AKT activation and ER stress pathway inhibition, diminishing mitochondrial dysfunction and decreasing neuronal pyroptosis through the ROS/MAPK/NF-κB pathway. These findings highlight Prx II potential therapeutic value in improving intracerebral hemorrhage outcomes by lessening secondary brain injury via critical signaling pathway modulation involved in neuronal pyroptosis.

CONCLUSIONS

Our study not only underlines Prx II importance in neuroprotection but also opens new therapeutic intervention avenues in intracerebral hemorrhage, stressing the complex interplay between redox regulation, ER stress, and mitochondrial dynamics in neuroinflammation and cell death management.

Mas receptor activation facilitates innate hematoma resolution and neurological recovery after hemorrhagic stroke in mice

BACKGROUND

Intracerebral hemorrhage (ICH) is a devastating neurological disease causing severe sensorimotor dysfunction and cognitive decline, yet there is no effective treatment strategy to alleviate outcomes of these patients. The Mas axis-mediated neuroprotection is involved in the pathology of various neurological diseases, however, the role of the Mas receptor in the setting of ICH remains to be elucidated.

METHODS

C57BL/6 mice were used to establish the ICH model by injection of collagenase into mice striatum. The Mas receptor agonist AVE0991 was administered intranasally (0.9 mg/kg) after ICH. Using a combination of behavioral tests, Western blots, immunofluorescence staining, hematoma volume, brain edema, quantitative-PCR, TUNEL staining, Fluoro-Jade C staining, Nissl staining, and pharmacological methods, we examined the impact of intranasal application of AVE0991 on hematoma absorption and neurological outcomes following ICH and investigated the underlying mechanism.

RESULTS

Mas receptor was found to be significantly expressed in activated microglia/macrophages, and the peak expression of Mas receptor in microglia/macrophages was observed at approximately 3-5 days, followed by a subsequent decline. Activation of Mas by AVE0991 post-treatment promoted hematoma absorption, reduced brain edema, and improved both short- and long-term neurological functions in ICH mice. Moreover, AVE0991 treatment effectively attenuated neuronal apoptosis, inhibited neutrophil infiltration, and reduced the release of inflammatory cytokines in perihematomal areas after ICH. Mechanistically, AVE0991 post-treatment significantly promoted the transformation of microglia/macrophages towards an anti-inflammatory, phagocytic, and reparative phenotype, and this functional phenotypic transition of microglia/macrophages by Mas activation was abolished by both Mas inhibitor A779 and Nrf2 inhibitor ML385. Furthermore, hematoma clearance and neuroprotective effects of AVE0991 treatment were reversed after microglia depletion in ICH.

CONCLUSIONS

Mas activation can promote hematoma absorption, ameliorate neurological deficits, alleviate neuron apoptosis, reduced neuroinflammation, and regulate the function and phenotype of microglia/macrophages via Akt/Nrf2 signaling pathway after ICH. Thus, intranasal application of Mas agonist ACE0991 may provide promising strategy for clinical treatment of ICH patients.

Advances in the research and application of neurokinin-1 receptor antagonists

Recently, the substance P (SP)/neurokinin-1 receptor (NK-1R) system has been found to be involved in various human pathophysiological disorders including the symptoms of coronavirus disease 2019 (COVID-19). Besides, studies in the oncological field have demonstrated an intricate correlation between the upregulation of NK-1R and the activation of SP/NK-1R system with the progression of multiple carcinoma types and poor clinical prognosis. These findings indicate that the modulation of SP/NK-1R system with NK-1R antagonists can be a potential broad-spectrum antitumor strategy. This review updates the latest potential and applications of NK-1R antagonists in the treatment of human diseases and cancers, as well as the underlying mechanisms. Furthermore, the strategies to improve the bioavailability and efficacy of NK-1R antagonist drugs are summarized, such as solid dispersion systems, nanonization, and nanoencapsulation. As a radiopharmaceutical therapeutic, the NK-1R antagonist aprepitant was originally developed as radioligand receptor to target NK-1R-overexpressing tumors. However, combining NK-1R antagonists with other drugs can produce a synergistic effect, thereby enhancing the therapeutic effect, alleviating the symptoms, and improving patients quality of life in several diseases and cancers.

Sesamin ameliorates nonalcoholic steatohepatitis through inhibiting hepatocyte pyroptosis in vivo and in vitro

Sesamin (Ses) is a natural lignan abundantly present in sesame and sesame oil. Pyroptosis, a newly identified type of pro-inflammatory programmed necrosis, contributes to the development of non-alcoholic steatohepatitis (NASH) when hepatocyte pyroptosis is excessive. In this study, Ses treatment demonstrated an improvement in hepatic damage in mice with high-fat, high-cholesterol diet-induced NASH and palmitate (PA)-treated mouse primary hepatocytes. Notably, we discovered, for the first time, that Ses could alleviate hepatocyte pyroptosis both in vivo and in vitro. Furthermore, treatment with phorbol myristate acetate, a protein kinase Cδ (PKCδ) agonist, increased PKCδ phosphorylation and attenuated the protective effects of Ses against pyroptosis in PA-treated mouse primary hepatocytes. Mechanistically, Ses treatment alleviated hepatocyte pyroptosis in NASH, which was associated with the regulation of the PKCδ/nod-like receptor family CARD domain-containing protein 4/caspase-1 axis. This study introduces a novel concept and target, suggesting the potential use of functional factors in food to alleviate liver damage caused by NASH.

Treatment of Intracerebral Hemorrhage with Traditional Chinese Medicine Monomer Wogonin by Modifying NLRP3 with METTL14 to Inhibit Neuronal Cell Pyroptosis

The aim of this study was to investigate the alleviating effect of wogonin on intracerebral hemorrhage (ICH) and its mechanism. The hemin-treated PC-12 cells were constructed to mimic ICH in vitro. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) analysis was used for cell viability measurement and flow cytometry was for pyroptosis detection. Enzyme-linked immunosorbent assay (ELISA) assay and western blot were used to detect the protein levels of pyroptosis-related proteins. The modification level of N6-methyladenosine (m6A) methylation was detected by quantitative real-time polymerase chain reaction (qRT-PCR) combined with m6A dot blot assays. Molecular docking experiments analyzed the binding of wogonin and METTL14 protein. The correlation between METTL14 and NLRP3 was confirmed by bioinformatics analysis and dual luciferase reporter gene detection. ICH was induced in mice injected with collagenase into the basal ganglia, and the neurobehavioral damage was evaluated. Triphenyltetrazolium chloride monohydrate (TTC) staining and neurological scores were used to assess brain damage in mice. The results demonstrated that wogonin alleviated neuronal cell pyroptosis, and was molecularly docked with METTL14. Overexpression of METTL14 partly reversed the protecting effects of wogonin on brain in vitro and in vivo. Furthermore, NLRP3 was methylated by METTL14. Taken together, wogonin inhibits neuronal pyroptosis and thus treats IHC by inhibiting METTL14 and its methylated NLRP3.

Mesenchymal Stem Cell Therapy in Acute Intracerebral Hemorrhage: A Dose-Escalation Safety and Tolerability Trial

BACKGROUND

We conducted a preliminary phase I, dose-escalating, safety, and tolerability trial in the population of patients with acute intracerebral hemorrhage (ICH) by using human allogeneic bone marrow-derived mesenchymal stem/stromal cells.

METHODS

Eligibility criteria included nontraumatic supratentorial hematoma less than 60 mL and Glasgow Coma Scale score greater than 5. All patients were monitored in the neurosciences intensive care unit for safety and tolerability of mesenchymal stem/stromal cell infusion and adverse events. We also explored the use of cytokines as biomarkers to assess responsiveness to the cell therapy. We screened 140 patients, enrolling 9 who met eligibility criteria into three dose groups: 0.5 million cells/kg, 1 million cells/kg, and 2 million cells/kg.

RESULTS

Intravenous administration of allogeneic bone marrow-derived mesenchymal stem/stromal cells to treat patients with acute ICH is feasible and safe.

CONCLUSIONS

Future larger randomized, placebo-controlled ICH studies are necessary to validate this study and establish the effectiveness of this therapeutic approach in the treatment of patients with ICH.

Prognostic significance of serum NLRC4 in patients with acute supratentorial intracerebral hemorrhage: A prospective longitudinal cohort study

Objective

Caspase activation and recruitment domain-containing protein 4 (NLRC4) is implicated in neuroinflammation. The aim of the study was to discern the potential ability of serum NLRC4 in assessment of prognosis after intracerebral hemorrhage (ICH).

Methods

In this prospective, observational study, serum NLRC4 levels were quantified in 148 acute supratentorial ICH patients and 148 controls. Severity was evaluated using the National Institutes of Health Stroke Scale (NIHSS) and hematoma volume, and poststroke 6-month functional outcome was estimated according to the modified Rankin Scale (mRS). Early neurologic deterioration (END) and 6-month poor outcome (mRS 3–6) were deemed as the two prognostic parameters. Multivariate models were established for investigating associations, and receiver operating characteristic (ROC) curves were configured to indicate predictive capability.

Results

Patients had substantially higher serum NLRC4 levels than controls (median, 363.2 pg/ml vs. 74.7 pg/ml). Serum NLRC4 levels had independent correlation with NIHSS scores [β, 0.308; 95% confidence interval (CI), 0.088–0.520], hematoma volume (β, 0.527; 95% CI, 0.385–0.675), serum C-reactive protein levels (β, 0.288; 95% CI, 0.109–0.341) and 6-month mRS scores (β, 0.239; 95% CI, 0.100–0.474). Serum NLRC4 levels above 363.2 pg/ml were independently predictive of END (odds ratio, 3.148; 95% CI, 1.278–7.752) and 6-month poor outcome (odds ratio, 2.468; 95% CI, 1.036–5.878). Serum NLRC4 levels significantly distinguished END risk [area under ROC curve (AUC), 0.765; 95% CI, 0.685–0.846] and 6-month poor outcome (AUC, 0.795; 95% CI, 0.721–0.870). In terms of predictive ability for 6-month poor outcome, serum NLRC4 levels combined with NIHSS scores and hematoma volume was superior to NIHSS scores combined with hematoma volume, NIHSS scores and hematoma volume (AUC, 0.913 vs. 0.870, 0.864 and 0.835; all P < 0.05). Nomograms were built to reflect prognosis and END risk of combination models, where serum NLRC4, NIHSS scores and hematoma volume were enforced. Calibration curves confirmed stability of combination models.

Conclusions

Markedly raised serum NLRC4 levels following ICH, in close relation to illness severity, are independently associated with poor prognosis. Such results are indicative of the notion that determination of serum NLRC4 may aid in severity assessment and prediction of functional outcome of ICH patients.

Evaluation of Serum NLRC4 as a Potential Prognostic Biochemical Marker in Humans with Severe Traumatic Brain Injury: A Prospective Cohort Study

Objective

Involvement of NLR CARD domain containing 4 (NLRC4) in neuroinflammation has been demonstrated. The aim of this study was to ascertain the prognostic role of serum NLRC4 in severe traumatic brain injury (sTBI).

Methods

In this prospective cohort study including 140 sTBI patients and 140 controls, serum NLRC4 levels were quantified. Follow-up time was 180 days after trauma and poor prognosis was designated as extended Glasgow outcome scale (GOSE) scores of 1-4. Severity correlations and prognosis associations were determined under multivariate models.

Results

Enhanced serum NLRC4 levels after sTBI, in comparison to controls (median, 0.8 ng/mL versus 0.1 ng/mL; P < 0.001), were independently correlated with Glasgow coma scale (GCS) scores (β, -0.091; 95% confidence interval (CI), -0.161-0.021; P = 0.011), Rotterdam computed tomography (CT) scores (β, 0.136; 95% CI, 0.024-0.248; P = 0.018), serum C-reactive protein levels (β, 0.016; 95% CI, 0.002-0.030; P = 0.025) and 180-day GOSE scores (β, -0.906; 95% CI, -1.632-0.180; P = 0.015); and were independently predictive of 180-day death (odds ratio, 4.307; 95% CI, 1.706-10.879; P = 0.014)), overall survival (hazard ratio, 2.360; 95% CI, 1.118-4.981; P = 0.040) and poor prognosis (odds ratio, 6.705; 95% CI, 2.889-15.561; P = 0.016). Under receiver operating characteristic curve, combination of serum NLRC4 levels, GCS scores and Rotterdam CT scores had significantly higher death predictive ability than Rotterdam CT scores (P = 0.040), but not than GCS scores (P = 0.070); and exhibited substantially higher predictive capability for poor prognosis than Rotterdam CT scores (P < 0.001) and GCS scores alone (P = 0.023).

Conclusion

There is a dramatical elevation of serum NLRC4 levels after sTBI, which has strong correlation with severity and inflammation, and is significantly associated with long-term death and poor outcome, substantializing serum NLRC4 as an inflammatory, prognostic biomarker in sTBI.