Coniferyl Aldehyde Inhibits the Inflammatory Effects of Leptomeningeal Cells by Suppressing the JAK2 Signaling

Smoking Impacts Alzheimer's Disease Progression Through Oral Microbiota Modulation

Alzheimer's disease (AD) is an important public health challenge with a limited understanding of its pathogenesis. Smoking is a significant modifiable risk factor for AD progression, and its specific mechanism is often interpreted from a toxicological perspective. However, microbial infections also contribute to AD, with oral microbiota playing a crucial role in its progression. Notably, smoking alters the ecological structure and pathogenicity of the oral microbiota. Currently, there is no systematic review or summary of the relationship between these three factors; thus, understanding this association can help in the development of new treatments. This review summarizes the connections between smoking, AD, and oral microbiota from existing research. It also explores how smoking affects the occurrence and development of AD through oral microbiota, and examines treatments for oral microbiota that delay the progression of AD. Furthermore, this review emphasizes the potential of the oral microbiota to act as a biomarker for AD. Finally, it considers the feasibility of probiotics and oral antibacterial therapy to expand treatment methods for AD.

Establishment of an MR1 Presentation Reporter Screening System and Identification of Phenylpropanoid Derivatives as MR1 Ligands

Mucosal-associated invariant T (MAIT) cells are innate-like T cells that are modulated by ligands presented on MHC class I-related proteins (MR1). These cells have attracted attention as potential drug targets because of their involvement in the initial response to infection and various disorders. Herein, we have established the MR1 presentation reporter assay system employing split-luciferase, which enables the efficient exploration of MR1 ligands. Using our screening system, we identified phenylpropanoid derivatives as MR1 ligands, including coniferyl aldehyde, which have an ability to inhibit the MR1-MAIT cell axis. Further, the structure-activity relationship study of coniferyl aldehyde analogs revealed the key structural features of ligands required for MR1 recognition. These results will contribute to identifying a broad range of endogenous and exogenous MR1 ligands and to developing novel MAIT cell modulators.

The gastrodin biosynthetic pathway in Pholidota chinensis Lindl. revealed by transcriptome and metabolome profiling

Pholidota chinensis Lindl. is an epiphytic or lithophytic perennial herb of Orchidaceae family used as a garden flower or medicinal plant to treat high blood pressure, dizziness and headache in traditional Chinese medicine. Gastrodin (GAS) is considered as a main bioactive ingredient of this herb but the biosynthetic pathway remains unclear in P. chinensis. To elucidate the GAS biosynthesis and identify the related genes in P. chinensis, a comprehensive analysis of transcriptome and metabolome of roots, rhizomes, pseudobulbs and leaves were performed by using PacBio SMART, Illumina Hiseq and Ultra Performance Liquid Chromatography Tandem Mass Spectrometry (UPLC-MS/MS). A total of 1,156 metabolites were identified by UPLC-MS/MS, of which 345 differential metabolites were mainly enriched in phenylpropanoid/phenylalanine, flavone and flavonol biosynthesis. The pseudobulbs make up nearly half of the fresh weight of the whole plant, and the GAS content in the pseudobulbs was also the highest in four tissues. Up to 23,105 Unigenes were obtained and 22,029 transcripts were annotated in the transcriptome analysis. Compared to roots, 7,787, 8,376 and 9,146 differentially expressed genes (DEGs) were identified in rhizomes, pseudobulbs and leaves, respectively. And in total, 80 Unigenes encoding eight key enzymes for GAS biosynthesis, were identified. Particularly, glycosyltransferase, the key enzyme of the last step in the GAS biosynthetic pathway had 39 Unigenes candidates, of which, transcript28360/f2p0/1592, was putatively identified as the most likely candidate based on analysis of co-expression, phylogenetic analysis, and homologous searching. The metabolomics and transcriptomics of pseudobulbs versus roots showed that 8,376 DEGs and 345 DEMs had a substantial association based on the Pearson's correlation. This study notably enriched the metabolomic and transcriptomic data of P. chinensis, and it provides valuable information for GAS biosynthesis in the plant.

Alpha7 Nicotinic Acetylcholine Receptor Antagonists Prevent Meningitic Escherichia coli-Induced Blood–Brain Barrier Disruptions by Targeting the CISH/JAK2/STAT5b Axis

Despite the availability of antibiotics over the last several decades, excessive antibiotic treatments for bacterial sepsis and meningitis (BSM) in children may result in several adverse outcomes. Hematogenous pathogens may directly induce permeability increases in human brain microvascular endothelial cells (HBMECs) and blood–brain barrier (BBB) dysfunctions. Our preliminary studies demonstrated that the alpha7 nicotinic acetylcholine receptor (α7nAChR) played an important role in the pathogenesis of BSM, accompanied by increasing cytokine-inducible SH2-containing protein (CISH) at the transcriptome level, but it has remained unclear how α7nAChR-CISH works mechanistically. The study aims to explore the underlying mechanism of α7nAChR and CISH during E. coli-induced BSM in vitro (HBMECs) and in vivo (α7nAChR-KO mouse). We found that in the stage of E. coli K1-induced BBB disruptions, α7nAChR functioned as the key regulator that affects the integrity of HBMECs by activating the JAK2–STAT5 signaling pathway, while CISH inhibited JAK2–STAT5 activation and exhibited protective effects against E. coli infection. Notably, we first validated that the expression of CISH could be regulated by α7nAChR in HBMECs. In addition, we determined the protective effects of MLA (methyllycaconitine citrate) and MEM (memantine hydrochloride) (functioning as α7nAChR antagonists) on infected HBMECs and suggested that the α7nAChR–CISH axis could explain the protective effects of the two small-molecule compounds on E. coli-induced HBMECs injuries and BBB disruptions. In conclusion, we dissected the α7nAChR/CISH/JAK2/STAT5 axis as critical for the pathogenesis of E. coli-induced brain microvascular leakage and BBB disruptions and provided novel evidence for the development of α7nAChR antagonists in the prevention of pediatric E. coli BSM.

Exploring ALDH2 expression and immune infiltration in HNSC and its correlation of prognosis with gender or alcohol intake

The aldehyde dehydrogenase 2 point mutation (ALDH2*2) is a common frequent human gene variant, especially in East Asians. However, the expression and mechanism of action of ALDH2 in HNSC remain unknown. The present study explored the clinical significance and immune characteristics of ALDH2 in HNSC. The receiver operating characteristic curve was analysed to assess the diagnostic value of ALDH2 expression. ALDH2 expression in normal tissues and HNSC tissues was evaluated by IHC, and we also analysed ALDH2 gene expression in 4 HNSC cell lines. ALDH2 expression was significantly reduced in HNSC tissues compared to normal tissues (p < 0.05). HNSC patients with high ALDH2 expression had a better prognosis compared to patients with low ALDH2 expression (p < 0.05). GSEA indicated that these gene sets were correlated with signalling pathways, including the JAK-STAT signalling pathway. Unexpectedly, we found a significant prognostic effect of ALDH2 for HNSC based on alcohol consumption and the male sex. The correlation between ALDH2 expression and immune inhibitors showed an effect for ALDH2 in modifying tumour immunology in HNSC, and there may be a possible mechanism by which ALDH2 regulates the functions of T cells in HNSC. In addition, we developed a prognostic nomogram for HNSC patients, which suggested that low ALDH2 expression indicated poor prognosis in HNSC patients who were males and alcoholics.