11β-HSD1 participates in epileptogenesis and the associated cognitive impairment by inhibiting apoptosis in mice

Edaravone dexborneol exerts anti-epileptic effects on rodent temporal lobe epilepsy by promoting NMDAR deactivation and inhibiting oxidative stress

BACKGROUND

Disease-modifying treatments with anti-epileptic effects are currently unavailable and urgently required for temporal lobe epilepsy (TLE). Combined therapy targeting multiple mechanisms may offer a promising anti-epileptic strategy, given the complex processes underlying epileptogenesis.

PURPOSE

This study evaluates the effects of Edaravone Dexbroneol, a combination of Edaravone and Dexborneol in 4:1, on rat and mouse TLE models and an in vitro epileptiform activity model.

METHODS

The Pilocarpine-induced rat TLE model and the Kainic acid-induced mouse TLE model were used to assess the in vivo effect of Edaravone and/or Dexbornel. Primary neurons were utilized to evaluate the in vitro effect of drugs using calcium imaging, electrophysiological and biochemical analyses, as well as RNA sequencing.

RESULTS

Treatment of Edaravone Dexbornel during the latent period significantly alleviated epileptic seizures in rodents, mitigated cognitive impairment, and inhibited neuronal loss and astrocytic activation. In vitro, Edaravone Dexborneol inhibited the action potentials and protected primary hippocampal neurons from Mg2+-free-induced neurite injury. All these effects were significantly more pronounced in the group treated with the Edaravone Dexborneol mixture compared to either drug used individually. Furthermore, Edaravone can significantly inhibit Mg2+-free-induced calcium oscillations in primary neurons, probably by promoting the deactivation of NMDA receptors. RNA sequencing and RT-PCR analysis revealed that synergetic regulation of lipid metabolism, oxidative stress, apoptosis, and calcium signaling probably underlay the neuroprotective effect of Edaravone Dexbornel on epileptic neurons.

CONCLUSION

Edaravone Dexborneol exhibits antiepileptic effects and may fill the gap in disease-modifying treatments for TLE.

Role of 11β-Hydroxysteroid Dehydrogenase and Mineralocorticoid Receptor on Alzheimer's Disease Onset: A Systematic Review

The role of 11β-HSD1 in Alzheimer's disease (AD) has garnered significant attention due to its involvement in glucocorticoid metabolism, neuroinflammation, and cognitive decline. This review explores the current understanding of 11β-HSD1 in AD, examining genetic, preclinical, and clinical research. Genetic studies have identified 11β-HSD1 polymorphisms that may influence AD risk, although findings remain inconsistent. Mechanistically, 11β-HSD1 promotes neurodegeneration through the dysregulation of glucocorticoid activity, contributing to hippocampal atrophy, amyloid plaque formation, and tau pathology. Preclinical studies have shown that 11β-HSD1 inhibitors offer neuroprotective effects, including enhanced cognitive function, reduced inflammation, and improved mitochondrial activity. However, clinical trials, including those involving ABT-384 and Xanamem, have produced mixed results, with no substantial cognitive improvements despite effective enzyme inhibition. These inconsistencies highlight the complexity of AD and the challenges in translating preclinical findings into clinical outcomes. Moreover, while 11β-HSD1 inhibition holds therapeutic potential, other strategies targeting neuroinflammation, autophagy, and glucocorticoid signaling are also being explored. Ongoing research is focusing on optimizing 11β-HSD1 inhibitors, identifying biomarkers for patient selection, and investigating combination therapies to enhance treatment efficacy. Ultimately, 11β-HSD1's role in AD presents a promising therapeutic target, but further studies are required to fully understand its potential in managing the disease.

Gut Microbiota Metabolites Mediate Bax to Reduce Neuronal Apoptosis via cGAS/STING Axis in Epilepsy

The beneficial effects of gut flora on reducing nerve cell apoptosis and inflammation and improving epilepsy (EP) symptoms have been reported, but the specific mechanism of action is still unclear. A series of in vitro and in vivo experiments revealed the relationship between gut microbiota metabolites and the cGAS/STING axis and their role in EP. These results suggest that antibiotic-induced dysbiosis of gut microbiota exacerbated epileptic symptoms, probiotic supplements reduced epileptic symptoms in mice. Antibiotics and probiotics altered the diversity and composition of gut microbiota. The changes in gut bacteria composition, such as in the abundance of Firmicutes, Bacteroidetes, Lactobacillus and Ruminococcus, were associated with the production of short-chain fatty acids (SCFA) in the gut. The concentrations of propionate, butyrate and isovalerate were changed after feeding antibiotics and probiotics, and the increase in butyrate levels reduced the expression of cGAS/STING in nerve cell further reduced Bax protein expression. The reduction of Bax protein attenuated the hippocampal neuron cell apoptosis in PTZ-induced EP and EP progression. Our findings provide new insights into the roles and mechanisms of action of the gut microbiota in attenuating EP symptoms and progression.

Astragalus polysaccharides ameliorate epileptogenesis, cognitive impairment, and neuroinflammation in a pentylenetetrazole-induced kindling mouse model

Background: Epilepsy is a prevalent neurological disease where neuroinflammation plays a significant role in epileptogenesis. Recent studies have suggested that Astragalus polysaccharides (APS) have anti-inflammatory properties, which make them a potential candidate for neuroprotection against central nervous system disease. Nevertheless, the extent of their effectiveness in treating epilepsy remains enigmatic. Therefore, our study aims to investigate the potential of APS to mitigate epileptogenesis and its comorbidities by exploring its underlying mechanism. Methods: Initially, we employed pentylenetetrazol-induced seizure mice to validate APS' effectiveness. Subsequently, we employed network pharmacology analysis to probe the possible targets and signaling pathways of APS in treating epilepsy. Ultimately, we verified the key targets and signaling pathways experimentally, predicting their mechanisms of action. Results: APS have been observed to disturb the acquisition process of kindling, leading to reduced seizure scores and a lower incidence of complete kindling. Moreover, APS has been found to improve cognitive impairments and prevent hippocampal neuronal damage during the pentylenetetrazole (PTZ)-kindling process. Subsequent network pharmacology analysis revealed that APS potentially exerted their anti-epileptic effects by targeting cytokine and toll-like receptor 4/nuclear factor kappa B (TLR4/NF-κB) signaling pathways. Finally, experimental findings showed that APS efficiently inhibited the activation of astrocytes and reduced the release of pro-inflammatory mediators, such as interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). In addition, APS impeded the activation of the TLR4/NF-κB signaling cascade in a PTZ-induced kindling mouse model. Conclusion: The outcomes of our study suggest that APS exerts an impact on epileptogenesis and mitigates cognitive impairment by impeding neuroinflammatory processes. The mechanism underlying these observations may be attributed to the modulation of the TLR4/NF-κB signaling pathway, resulting in a reduction of the release of inflammatory mediators. These findings partially agree with the predictions derived from network pharmacology analyses. As such, APS represents a potentially innovative and encouraging adjunct therapeutic option for epileptogenesis and cognitive deficit.

Repeated neonatal Needle-pricking stimulation alter neurodevelopment in adolescent rats

OBJECTIVE

To explore the repeated pain stimulation in neonatal rats affects their cognitive and memory abilities during puberty, and the proliferation expression of hippocampal neurons.

METHODS

Postnatal 1 day (P1) SD rats were randomly divided into two groups, and the skin of the needle group was pricked for seven days consecutively while the skin of the control group was stroked for the same period of time. The rats in both groups were weighed every week, and the Morris water maze experiment was performed from P44 to P49 to test the cognitive and memory abilities of the rats. On P50, the hippocampal tissue was extracted for observation of pathological features and the expressions of Ki-67 and caspase 3 were determined.

RESULTS

With the increase of the days, the body weight of the rats in the needle group increased slightly slower than that of the control group. The escape latency of the needle group was significantly higher than that of the control group in the water maze test at P45 and P48, and the number of times the rats crossing the platform in the needle group was lower than that of the control group. The HE staining of the hippocampal tissue showed that the cells in the needle group were disorganized, with irregular morphology. Under the electron microscope, the structure of neuron cells and organelles is changed in the hippocampal CA1 region of rats. It showed a decrease in the Ki-67 expression and an increase in caspase 3 in the needle group.

CONCLUSION

Repeated experience of needle-pricking stimulation in neonatal rats can cause cognitive impairment and memory loss in puberty, disrupt hippocampal organization, and diminish neuronal proliferation.