Extract of Aster koraiensis Nakai Leaf Ameliorates Memory Dysfunction via Anti-inflammatory Action

Transcriptional-profile changes in the medial geniculate body after noise-induced tinnitus

Tinnitus is a disturbing condition defined as the occurrence of acoustic hallucinations with no actual sound. Although the mechanisms underlying tinnitus have been explored extensively, the pathophysiology of the disease is not completely understood. Moreover, genes and potential treatment targets related to auditory hallucinations remain unknown. In this study, we examined transcriptional-profile changes in the medial geniculate body after noise-induced tinnitus in rats by performing RNA sequencing and validated differentially expressed genes via quantitative polymerase chain reaction analysis. The rat model of tinnitus was established by analyzing startle behavior based on gap-pre-pulse inhibition of acoustic startles. We identified 87 differently expressed genes, of which 40 were upregulated and 47 were downregulated. Pathway-enrichment analysis revealed that the differentially enriched genes in the tinnitus group were associated with pathway terms, such as coronavirus disease COVID-19, neuroactive ligand-receptor interaction. Protein-protein-interaction networks were established, and two hub genes (Rpl7a and AC136661.1) were identified among the selected genes. Further studies focusing on targeting and modulating these genes are required for developing potential treatments for noise-induced tinnitus in patients.

Borneol-Modified Schisandrin B Micelles Cross the Blood-Brain Barrier To Treat Alzheimer's Disease in Aged Mice

Objective: Schisandrin B (Sch B) is a bioactive dibenzocyclooctadiene derizative that is prevalent in the fruit of Schisandra chinensis. Numerous studies have demonstrated that Sch B has a neuroprotective action by reducing oxidative stress and effectively preventing inflammation. It follows that Sch B is a potential treatment for Alzheimer's disease (AD). However, the drug's solubility, bioavailability, and lower permeability of the blood-brain barrier (BBB) can all reduce its efficacy during the therapy process. Therefore, this study constructed borneol-modified schisandrin B micelles (Bor-Sch B-Ms), which increase brain targeting by accurately delivering medications to the brain, effectively improving bioavailability. High therapeutic efficacy has been achieved at the pathological site. Methods: Bor-Sch B-Ms were prepared using the thin film dispersion approach in this article. On the one hand, to observe the targeting effect of borneol, we constructed a blood-brain barrier (BBB) model in vitro and studied the ability of micelles to cross the BBB. On the other hand, the distribution of micelle drugs and their related pharmacological effects on neuroinflammation, oxidative stress, and neuronal damage were studied through in vivo administration in mice. Results: In vitro studies have demonstrated that the drug uptake of bEnd.3 cells was increased by the borneol alteration on the surface of the nano micelles, implying that Bor-Sch B-Ms can promote the therapeutic effect of N2a cells. This could result in more medicines entering the BBB. In addition, in vivo studies revealed that the distribution and circulation time of medications in the brain tissue were significantly higher than those in other groups, making it more suitable for the treatment of central nervous system diseases. Conclusion: As a novel nanodrug delivery system, borneol modified schisandrin B micelles have promising research prospects in the treatment of Alzheimer's disease.

The effects of noise exposure on hippocampal cognition in C57BL/6 mice via transcriptomics

BACKGROUND

Noise is an important environmental stressor in the industrialized world and has received increasing attention in recent years. Although epidemiological research has extensively demonstrated the relationship between noise and cognitive impairment, the specific molecular mechanisms and targets remain to be fully explored and understood.

METHODS

To address this issue, 5-month-old C57BL/6 mice were divided into two groups, with one group exposed to white noise at 98 dB. The effects of noise on cognition in mice were investigated through molecular biology and behavioral experiments. Subsequently, transcriptomic sequencing of the hippocampus in both groups of mice was performed and enrichment analysis of differentially expressed genes (DEGs) was conducted using KEGG and GO databases. Furthermore, LASSO analysis was used to further narrow down the relevant DEGs, followed by enrichment analysis of these genes using KEGG and GO databases. The DEGs were further validated by rt-qPCR.

RESULTS

Following noise exposure, the hippocampus levels of inflammation-related factors increased, the phosphorylation of Tau protein increased, the postsynaptic density protein decreased, the number of Nissl bodies decreased, and cell shrinkage in the hippocampus increased. Moreover, the behavioral experiments manifest characteristics indicative of a decline in cognitive.A total of 472 DEGs were identified through transcriptomic analysis, and seven relevant genes were screened by the LASSO algorithm, which were further validated by PCR to confirm their consistency with the omics results.

CONCLUSION

In conclusion, noise exposure affects cognitive function in mice through multiple pathways, and the omics results provide new evidence for the cognitive impairment induced by noise exposure.

Ginkgo biloba Extract Drives Gut Flora and Microbial Metabolism Variation in a Mouse Model of Alzheimer's Disease

Alzheimer's disease (AD) is a complex neurodegenerative disease. Numerous investigations have demonstrated that medications that regulate the "brain-gut" axis can ameliorate disease symptoms of AD. Studies have shown that Ginkgo biloba extract (EGb) is involved in intestinal metabolism to meet the goal of illness treatment. EGb is currently utilized extensively in the clinical prevention and treatment of cardiovascular and cerebrovascular diseases. However, the regulatory effect of EGb on intestinal flora and its metabolites in AD pathology remains largely speculative. In this study, the Morris water maze test showed a significant improvement of spatial memory in the AD mouse model (APP/PS1 mice) after EGb treatment. We next confirmed the positive effects of EGb on the gut flora and metabolites of APP/PS1 mice and further showed that EGb treatment reshaped the disturbed gut microbiome, in particular by reducing the Firmicutes/Bacteroides ratio and increasing the abundance of Bacteroidetes, Uroviricota, Streptophyta, and Spirochaetes. Meanwhile, a non-targeted metabolomics analysis showed that EGb treatment significantly reversed the dysfunction of the microbial metabolic phenotype by altering Limosilactobacillus and Parvibacte, with 300 differential metabolites modulated (131 up-regulated, 169 down-regulated). Our findings highlight the significant regulatory impact of EGb on intestinal microflora and microbial metabolism in AD mice models and provide a potential therapeutic strategy for AD.