Aß25-35-induced autophagy and apoptosis are prevented by the CRMP2-derived peptide ST2-104 (R9-CBD3) via a CaMKKß/AMPK/mTOR signaling hub.

We previously reported that the peptide ST2-104 (CBD3, for Ca2+ channel-binding domain 3), derived from the collapsin response mediator protein 2 (CRMP2)-a cytosolic phosphoprotein, protects neuroblastoma cells against ß-amyloid (Aß) peptide-mediated toxicity through engagement of a phosphorylated CRMP2/NMDAR pathway. Abnormal aggregation of Aß peptides (e.g., Aß25-35) leads to programmed cell death (apoptosis) as well autophagy-both of which contribute to Alzheimer's disease (AD) progression. Here, we asked if ST2-104 affects apoptosis and autophagy in SH-SY5Y neuroblastoma challenged with the toxic Aß25-35 peptide and subsequently mapped the downstream signaling pathways involved. ST2-104 protected SH-SY5Y cells from death following Aß25-35 peptide challenge by reducing apoptosis and autophagy as well as limiting excessive calcium entry. Cytotoxicity of SHY-SY5Y cells challenged with Aß25-35 peptide was blunted by ST2-104. The autophagy activator Rapamycin blunted the anti-apoptotic activity of ST2-104. ST2-104 reversed Aß25-35-induced apoptosis via inhibiting Ca2+/CaM-dependent protein kinase kinase ß (CaMKKß)-mediated autophagy, which was partly enhanced by STO-609 (an inhibitor of CaMKKß). ST2-104 attenuated neuronal apoptosis by inhibiting autophagy through a CaMKKß/AMPK/mTOR signaling hub. These findings identify a mechanism whereby, in the face of Aß25-35, the concerted actions of ST2-104 leads to a reduction in intracellular calcium overload and inhibition of the CaMKKß/AMPK/mTOR pathway resulting in attenuation of autophagy and cellular apoptosis. These findings define a mechanistic framework for how ST2-104 transduces "outside" (calcium channels) to "inside" signaling (CaMKKß/AMPK/mTOR) to confer neuroprotection in AD.

Intra-Anterior Chamber Injection of Ranibizumab in Advanced Pediatric Vitreoretinal Diseases.

Importance: Anti-vascular endothelial growth factor (VEGF) treatment through intravitreal or subretinal administrations has been proven effective for VEGF-driven pediatric vitreoretinal diseases but are not feasible for advanced cases, such as shallow traction retinal detachments or peripheral circumferential retinal detachments which adhere to the lens. Intra-anterior chamber injection (IAcI) of anti-VEGF may be a viable alternative in such cases but needs evaluation. Objective: To investigate the effects and safety of IAcI of anti-VEGF to treat VEGF-driven pediatric vitreoretinal diseases. Design, Setting, and Participants: This was a retrospective observational case series study conducted at Xinhua Hospital, affiliated with Shanghai Jiao Tong University School of Medicine in China. The study included 14 eyes of 13 children diagnosed with vitreoretinal disease exhibiting elevated vascular activity between January and August 2023. Intervention: IAcI with ranibizumab. Main Outcomes and Measures: Retinal vascular abnormalities, vitreous hemorrhage resolution, and complications 1 month and 3 months after injection. Results: Of 13 patients included in this study, 12 were male. The mean age was 4.6 years (range, 1 month to 9 years). Six patients were diagnosed with familial exudative vitreoretinopathy, 4 with morning glory syndrome, 1 with retinopathy of prematurity, and 2 with chronic retinal detachments of unknown causes. At 1-month postoperative follow-up, vascular activity had decreased in 14 of 14 eyes. At 3-month follow-up, vascular activity had resolved in 7 of 14 eyes, persisted in 6 of 14 eyes, and reactivated in 1 of 14 eyes. On final observation, no complications were reported. Conclusions and Relevance: These findings support the possibility of treatment using IAcI with ranibizumab to decrease retinal vascular abnormalities in familial exudative vitreoretinopathy or retinopathy of prematurity or related conditions, but further studies are needed to understand more precise benefits and risks. This approach might be considered in cases where intravitreal or subretinal injection are not feasible, recognizing the limitations of these findings and that longer-term outcomes still need to be monitored.

Single-cell and spatial transcriptomics reveal POSTN+ cancer-associated fibroblasts correlated with immune suppression and tumour progression in non-small cell lung cancer.

BACKGROUND: Cancer-associated fibroblasts (CAFs) are potential targets for cancer therapy. Due to the heterogeneity of CAFs, the influence of CAF subpopulations on the progression of lung cancer is still unclear, which impedes the translational advances in targeting CAFs. METHODS: We performed single-cell RNA sequencing (scRNA-seq) on tumour, paired tumour-adjacent, and normal samples from 16 non-small cell lung cancer (NSCLC) patients. CAF subpopulations were analyzed after integration with published NSCLC scRNA-seq data. SpaTial enhanced resolution omics-sequencing (Stereo-seq) was applied in tumour and tumour-adjacent samples from seven NSCLC patients to map the architecture of major cell populations in tumour microenvironment (TME). Immunohistochemistry (IHC) and multiplexed IHC (mIHC) were used to validate marker gene expression and the association of CAFs with immune infiltration in TME. RESULTS: A subcluster of myofibroblastic CAFs, POSTN+ CAFs, were significantly enriched in advanced tumours and presented gene expression signatures related to extracellular matrix remodeling, tumour invasion pathways and immune suppression. Stereo-seq and mIHC demonstrated that POSTN+ CAFs were in close localization with SPP1+ macrophages and were associated with the exhausted phenotype and lower infiltration of T cells. POSTN expression or the abundance of POSTN+ CAFs were associated with poor prognosis of NSCLC. CONCLUSIONS: Our study identified a myofibroblastic CAF subpopulation, POSTN+ CAFs, which might associate with SPP1+ macrophages to promote the formation of desmoplastic architecture and participate in immune suppression. Furthermore, we showed that POSTN+ CAFs associated with cancer progression and poor clinical outcomes and may provide new insights on the treatment of NSCLC.

Mueller matrix imaging of pathological slides with plastic coverslips.

Mueller matrix microscopy is capable of polarization characterization of pathological samples and polarization imaging based digital pathology. In recent years, hospitals are replacing glass coverslips with plastic coverslips for automatic preparations of dry and clean pathological slides with less slide-sticking and air bubbles. However, plastic coverslips are usually birefringent and introduce polarization artifacts in Mueller matrix imaging. In this study, a spatial frequency based calibration method (SFCM) is used to remove such polarization artifacts. The polarization information of the plastic coverslips and the pathological tissues are separated by the spatial frequency analysis, then the Mueller matrix images of pathological tissues are restored by matrix inversions. By cutting two adjacent lung cancer tissue slides, we prepare paired samples of very similar pathological structures but one with a glass coverslip and the other with a plastic coverslip. Comparisons between Mueller matrix images of the paired samples show that SFCM can effectively remove the artifacts due to plastic coverslip.

Comprehensive single-cell transcriptomic and proteomic analysis reveals NK cell exhaustion and unique tumor cell evolutionary trajectory in non-keratinizing nasopharyngeal carcinoma.

BACKGROUND: Nonkeratinizing nasopharyngeal carcinoma (NK-NPC) has a strong association with Epstein-Barr virus (EBV) infection. The role of NK cells and the tumor cell evolutionary trajectory in NK-NPC remain unclear. In this study, we aim to investigate the function of NK cell and the evolutionary trajectory of tumor cells in NK-NPC by single-cell transcriptomic analysis, proteomics and immunohistochemistry. METHODS: NK-NPC (n = 3) and normal nasopharyngeal mucosa cases (n = 3) were collected for proteomic analysis. Single-cell transcriptomic data of NK-NPC (n = 10) and nasopharyngeal lymphatic hyperplasia (NLH, n = 3) were obtained from Gene Expression Omnibus (GSE162025 and GSE150825). Quality control, dimension reduction and clustering were based on Seurat software (v4.0.2) process and batch effects were removed by harmony (v0.1.1) software. Normal cells of nasopharyngeal mucosa and tumor cells of NK-NPC were identified using copykat software (v1.0.8). Cell-cell interactions were explored using CellChat software (v1.4.0). Tumor cell evolutionary trajectory analysis was performed using SCORPIUS software (v1.0.8). Protein and gene function enrichment analyses were performed using clusterProfiler software (v4.2.2). RESULTS: A total of 161 differentially expressed proteins were obtained between NK-NPC (n = 3) and normal nasopharyngeal mucosa (n = 3) by proteomics (log2 fold change > 0.5 and P value < 0.05). Most of proteins associated with the nature killer cell mediated cytotoxicity pathway were downregulated in the NK-NPC group. In single cell transcriptomics, we identified three NK cell subsets (NK1-3), among which NK cell exhaustion was identified in the NK3 subset with high ZNF683 expression (a signature of tissue-resident NK cell) in NK-NPC. We demonstrated the presence of this ZNF683 + NK cell subset in NK-NPC but not in NLH. We also performed immunohistochemical experiments with TIGIT and LAG3 to confirm NK cell exhaustion in NK-NPC. Moreover, the trajectory analysis revealed that the evolutionary trajectory of NK-NPC tumor cells was associated with the status of EBV infection (active or latent). The analysis of cell-cell interactions uncovered a complex network of cellular interactions in NK-NPC. CONCLUSIONS: This study revealed that the NK cell exhaustion might be induced by upregulation of inhibitory receptors on the surface of NK cells in NK-NPC. Treatments for the reversal of NK cell exhaustion may be a promising strategy for NK-NPC. Meanwhile, we identified a unique evolutionary trajectory of tumor cells with active status of EBV-infection in NK-NPC for the first time. Our study may provide new immunotherapeutic targets and new sight of evolutionary trajectory involving tumor genesis, development and metastasis in NK-NPC.

IgG4-related disease with kidney and lymph nodes involvement: a case-based review.

IgG4-related disease (IgG4-RD), a rare immune-mediated chronic fibro-inflammatory condition, has various initial symptoms, thus posing diagnostic and therapeutic challenges. Here, we report a case of IgG4-RD in a 35-year-old man with initial clinical symptoms of facial edema and recent onset of proteinuria. It took more than 1 year from the onset of clinical symptoms to diagnosis. Pathological examination of renal biopsy revealed significant renal interstitial lymphoid tissue hyperplasia simulating growth pattern of lymphoma. Immunohistochemical (IHC) staining results showed that CD4 + T lymphocyte hyperplasia was dominant. There was no significant deletion of CD2/CD3/CD5/CD7. No monoclone was detected in TCR gene rearrangement. IHC staining showed that the number of IgG4-positive cells was greater than 100/HPF. The ratio of IgG4/IgG was greater than 40%. Combined with clinically examinations, IgG4-related tubulointerstitial nephritis was considered. Further cervical lymph node biopsy results suggested IgG4-related lymphadenopathy. He received methylprednisolone 40 mg/day intravenously for 10 days, leading to normal results of laboratory tests and clinical manifestations. The patient had a good prognosis without recurrence during 14 months of follow-up. This case report can be used as a reference for early diagnosis and treatment of such patients in the future.

Changes in bacterial community structures in soil caused by migration and aging of microplastics.

Microplastics (MPs) are classified as emerging pollutants and greatly threatens soil ecosystems. To determine the impact of microplastic migration on soil bacterial diversity, we conducted a 90-day indoor soil column simulation test. Soil and microplastic (granular polystyrene, polypropylene MPs) samples were collected from different soil layers on days 30, 60, and 90. The downward migration trend of MPs was obvious, and its surface functional groups, hydrophobic properties, and crystallinity changed. Bacterial diversity was significantly higher in the surrounding soil than on microplastic surfaces. Also, the topsoil has more bacterial diversity than the middle soil. A higher number of OTUs were detected on microplastic surfaces for the middle soil than in the topsoil. Proteobacteria abundance on microplastic surfaces in the topsoil gradually increased over the course of the experiment, while an opposite trend was observed for the middle soil. Nevertheless, Proteobacteria abundances in both layers were higher than in the surrounding soils. MPs alters the bacterial community composition of soils and provides unique substrates for colonization. The impacts of MPs on soil bacterial communities were better understood in this study. Our findings highlighted the relevance of MPs in soil ecosystems as well as the potential threats they pose.

Alleviation of Myocardial Inflammation in Diabetic Rats by Flavonoid Extract of Helichrysum Arenarium and Its Effect on Damaged Myocardial Cells Induced by High Glucose.

Objective: To investigate the effects of helichrysum arenarium flavonoid extract on high glucose damaged cardiomyocytes and the alleviation of myocardial inflammation in diabetic rats. Methods: The study was divided into two parts, the first part was a cellular experiment in which a high-glucose cardiomyocyte injury model (H9C2) was established using a high-glucose culture medium, divided into low (group N1, 6.25 µg/mL), medium (group N2, 12.5 µg/mL), high dose group (group N3, 25 µg/mL) of helichrysum arenarium intervention and a model control group. The levels of enzyme activities [creatine kinase (CK) and lactate dehydrogenase (LDH)] in each group of H9c2 cells were measured by Enzyme-linked immunosorbent assay (ELISA), the expression levels of apoptotic proteins (Bax and Bcl-2) by western blot (WB), and the expression levels of inflammatory factors [tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-6 (IL-6)] by RT-qPCR. The second part is animal experiments, after establishing the diabetic rat model, we used helichrysum arenarium flavonoid extract to intervene SD rats, divided into helichrysum arenarium intervention low (group S1, 250 mg/kg), medium (group S2, 500 mg/kg), high dose group (group S3, 1 g/kg), SD rat model group. Hematoxylin-eosin (HE) staining was used to observe myocardial tissue lesions, and Real Time Quantitative PCR (RT-qPCR) method was used to detect inflammatory (TNF-α, IL-1ß, and IL-6) infiltration in myocardial tissue. Results: Cellular experiments: The activity levels of enzymes such as CK and LDH and the levels of inflammatory factors such as TNF-α, IL-1ß, and IL-6 in damaged cardiac myocytes were significantly decreased after helichrysum arenarium intervention; the expression levels of Bax protein were significantly down-regulated and the expression levels of Bcl-2 protein expression were significantly up-regulated. Animal experiment: HE staining showed that the model group had widened intercellular spaces, interstitial edema and obvious inflammatory cell infiltration in cardiac muscle tissue. After the intervention of helichrysum arenarium, the collagen fibers of rat myocardial cells were significantly reduced and cell degeneration was alleviated. Animal experiment: HE staining showed that the model group had widened intercellular spaces, interstitial edema and obvious inflammatory cell infiltration in cardiac muscle tissue. After the intervention of helichrysum arenarium, the collagen fibers of rat myocardial cells were significantly reduced and cell degeneration was alleviated; the levels of TNF-α, IL-1ß, IL-6 and other inflammatory factors in myocardial tissues were significantly decreased. Conclusion: The helichrysum arenarium flavonoid extract can reduce the degree of damage of H9C2 cells induced by high glucose and decrease the cellular inflammatory response, and its mechanism of action may be achieved by regulating the apoptotic factors Bax and Bcl-2. In addition, the extract of helichrysum arenarium can reduce the histopathological damage of myocardium in diabetic rats, decrease the inflammatory response in the tissue, and achieve the effect of myocardial protection.

MicroRNAs as potential biomarkers for the diagnosis of inflammatory bowel disease: a systematic review and meta-analysis.

OBJECTIVE: The clinical importance of aberrantly expressed microRNAs (miRNAs) in diagnosing inflammatory bowel disease (IBD) has not been well established, so was investigated in this systematic review and meta-analysis. METHODS: Articles in online databases from inception to March 17, 2021 were retrieved. Random effects meta-analysis was used to obtain sensitivity, specificity, positive (PLRs) and negative likelihood ratios (NLRs), diagnostic odds ratios (DORs), and areas under the curve (AUC) with 95% confidence intervals (CI) for IBD diagnosis. RESULTS: Of 117 studies reporting altered miRNA expression in IBD included in the systematic review, 15 involving 937 patients with IBD and 707 controls, 22 miRNAs, and two miRNA panels were eligible for meta-analysis. Pooled analyses showed a moderate diagnostic accuracy for miRNAs in the IBD diagnosis, with a sensitivity of 0.80 (95% CI: 0.79-0.82), specificity of 0.84 (95% CI: 0.82-0.86), DOR of 21.19 (95% CI: 13.90-32.31), and AUC of 0.89. Subgroup analyses revealed a better performance in patients with ulcerative colitis (AUC, 0.93) than Crohn's disease (AUC, 0.84). Consistent upregulation of miR-21, miR-16, and miR-192 in blood with a high-moderate diagnostic accuracy was found in at least two studies. CONCLUSIONS: These findings suggest miRNAs are credible diagnostic biomarkers in IBD.

Three Novel Variants of CEP290 and CC2D2DA and a Link Between ZNF77 and SHH Signaling Pathway Are Found in Two Meckel-Gruber Syndrome Fetuses.

Meckel-Gruber syndrome (MKS) is a rare lethal autosomal recessive inherited disorder. Missed diagnosis might happen in clinical works due to an unclear genotype-phenotype correlation. We analyzed two families visiting our center; the parents are normal; each of the family aborted a fetus at 12WG. Following ultrasonography and pathological examination, both were diagnosed as MKS. Whole exome sequencing identified a compound heterozygous of two novel variants of CEP290 and a heterozygous of a novel variant of CC2D2A. Frameshift mutations in ZNF77 were also detected. Western blot analyzing whole-brain tissue showed that the expression of ZNF77, CC2D2A, and CEP290 was enhanced. HEK293T transfected with over-expression wildtype/mutated ZNF77 plasmid showed that SHH was increased in wildtype ZNF77 cells, while SHH and CC2D2A were increased in mutated ZNF77 cells. Our research provided two novel pathogenic variants of CEP290 and CC2D2A and suggested that ZNF77 might promote the expression of CC2D2A and regulate the amount of SHH.

Study on the molecular mechanism of Guizhi Jia Shaoyao decoction for the treatment of knee osteoarthritis by utilizing network pharmacology and molecular docking technology.

BACKGROUND AND OBJECTIVE: Guizhi Jia Shaoyao decoction (GSD) is widely used in the clinical treatment of knee osteoarthritis (KOA). However, the underlying molecular mechanisms remain unclear. The aim of this study was to explore functional mechanisms of GSD in treating KOA by utilizing network pharmacology-based approaches. METHODS: Candidate components and targets of GSD were retrieved from the Traditional Chinese Medicine Systems Pharmacology database. NCBI, Genecards, Drugbank, and Therapeutic Target Database (TTD) were used to establish a target database for KOA. Then, an interactive network diagram of "drugs-active components-targets" was plotted with Cytoscape open source bioinformatics software. A protein-protein interaction network was constructed and related protein interaction relationships were analyzed based on the STRING database. Gene ontology analysis and Kyoto Encyclopedia of Genes and Genomes pathway-enrichment analysis were conducted based on intersected targets. Molecular docking provided an assessment tool for verifying binding of components and targets. It was performed by AutoDock molecular modeling simulation software. RESULTS: In all, 103 active components were successfully identified, and corresponding 133 targets were searched for treating KOA. Functional enrichment analysis suggested that GSD exerts its pharmacological effect in treating KOA by regulating multiple pathways, such as PI3K-Akt, tumor necrosis factor, Toll-like receptor (TLR), and nuclear factor kappa B signaling pathways. Molecular docking analysis depicted that representative components bound firmly to key targets. CONCLUSION: This study revealed the synergistic effects of multiple components, targets, and pathways of GSD for treating KOA. This would enhance the understanding of potential molecular mechanisms of GSD for treating KOA and lay a foundation for further experimental research.

Inhibition of autophagy by CRMP2-derived peptide ST2-104 (R9-CBD3) via a CaMKKß/AMPK/mTOR pathway contributes to ischemic postconditioning-induced neuroprotection against cerebral ischemia-reperfusion injury.

Cerebral ischemia, a common cerebrovascular disease, is characterized by functional deficits and apoptotic cell death. Autophagy, a type of programmed cell death, plays critical roles in controlling neuronal damage and metabolic homeostasis, and has been inextricably linked to cerebral ischemia. We previously identified a short peptide aptamer from collapsin response mediator protein 2 (CRMP2), designated the Ca2+ channel-binding domain 3 (CBD3) peptide, that conferred protection against excitotoxicity and traumatic brain injury. ST2-104, a nona-arginine (R9)-fused CBD3 peptide, exerted beneficial effects on neuropathic pain and was neuroprotective in a model of Alzheimer's disease; however, the effect of ST2-104 on cerebral ischemia and its mechanism of action have not been studied. In this study, we modeled cerebral ischemia-reperfusion injury in rats with the middle cerebral artery occlusion (MCAO) as well as challenged SH-SY5Y neuroblastoma cells with glutamate to induce toxicity to interrogate the effects of ST2-104 on autophagy following ischemic/excitotoxic insults. ST2-104 reduced the infarct volume and improved the neurological score of rats subjected to MCAO. ST2-104 protected SH-SY5Y cells from death following glutamate exposure via blunting apoptosis and autophagy as well as limiting excessive calcium entry. 3-Methyladenine (3-MA), an inhibitor of autophagy, promoted the effects of ST2-104 in inhibiting apoptosis triggered by glutamate while rapamycin, an activator of autophagy, failed to do so. ST2-104 peptide reversed glutamate-induced apoptosis via inhibiting Ca2+/CaM-dependent protein kinase kinase ß (CaMKKß)-mediated autophagy, which was partly enhanced by STO-609 (an inhibitor of CaMKKß). ST2-104 attenuated neuronal apoptosis by inhibiting autophagy through CaMKKß/AMPK/mTOR pathway. Our results suggest that the neuroprotective effect of ST2-104 are due to actions on the crosstalk between apoptosis and autophagy via the CaMKKß/AMPK/mTOR signaling pathway. The findings present novel insights into the potential neuroprotection of ST2-104 in cerebral ischemia.

Identification of an immune prognostic 11-gene signature for lung adenocarcinoma.

BACKGROUND: The immunological tumour microenvironment (TME) has occupied a very important position in the beginning and progression of non-small cell lung cancer (NSCLC). Prognosis of lung adenocarcinoma (LUAD) remains poor for the local progression and widely metastases at the time of clinical diagnosis. Our objective is to identify a potential signature model to improve prognosis of LUAD. METHODS: With the aim to identify a novel immune prognostic signature associated with overall survival (OS), we analysed LUADs extracted from The Cancer Genome Atlas (TCGA). Immune scores and stromal scores of TCGA-LUAD were downloaded from Estimation of STromal and Immune cells in MAlignant Tumour tissues Expression using data (ESTIMATE). LASSO COX regression was applied to build the prediction model. Then, the prognostic gene signature was validated in the GSE68465 dataset. RESULTS: The data from TCGA datasets showed patients in stage I and stage II had higher stromal scores than patients in stage IV (P < 0.05), and for immune score patients in stage I were higher than patients in stage III and stage IV (P < 0.05). The improved overall survivals were observed in high stromal score and immune score groups. Patients in the high-risk group exhibited the inferior OS (P = 2.501e - 05). By validating the 397 LUAD patients from GSE68465, we observed a better OS in the low-risk group compared to the high-risk group, which is consistent with the results from the TCGA cohort. Nomogram results showed that practical and predicted survival coincided very well, especially for 3-year survival. CONCLUSION: We obtained an 11 immune score related gene signature model as an independent element to effectively classify LUADs into different risk groups, which might provide a support for precision treatments. Moreover, immune score may play a potential valuable sole for estimating OS in LUADs.

Maternal Folic Acid Supplementation Mediates Offspring Health via DNA Methylation.

The clinical significance of periconceptional folic acid supplementation (FAS) in the prevention of neonatal neural tube defects (NTDs) has been recognized for decades. Epidemiological data and experimental findings have consistently been indicating an association between folate deficiency in the first trimester of pregnancy and poor fetal development as well as offspring health (i.e., NTDs, isolated orofacial clefts, neurodevelopmental disorders). Moreover, compelling evidence has suggested adverse effects of folate overload during perinatal period on offspring health (i.e., immune diseases, autism, lipid disorders). In addition to several single-nucleotide polymorphisms (SNPs) in genes related to folate one-carbon metabolism (FOCM), folate concentrations in maternal serum/plasma/red blood cells must be considered when counseling FAS. Epigenetic information encoded by 5-methylcytosines (5mC) plays a critical role in fetal development and offspring health. S-adenosylmethionine (SAM), a methyl donor for 5mC, could be derived from FOCM. As such, folic acid plays a double-edged sword role in offspring health via mediating DNA methylation. However, the underlying epigenetic mechanism is still largely unclear. In this review, we summarized the link across DNA methylation, maternal FAS, and offspring health to provide more evidence for clinical guidance in terms of precise FAS dosage and time point. Future studies are, therefore, required to set up the reference intervals of folate concentrations at different trimesters of pregnancy for different populations and to clarify the epigenetic mechanism for specific offspring diseases.

Lysionotin attenuates Staphylococcus aureus pathogenicity by inhibiting α-toxin expression.

α-Toxin, one of the best known pore-forming proteins produced by Staphylococcus aureus (S. aureus), is a critical virulence factor in multiple infections. The necessity of α-toxin for S. aureus pathogenicity suggests that this toxin is an important target for the development of a potential treatment strategy. In this study, we showed that lysionotin, a natural compound, can inhibit the hemolytic activity of culture supernatants by S. aureus by reducing α-toxin expression. Using real-time PCR analysis, we showed that transcription of hla (the gene encoding α-toxin) and agr (the locus regulating hla) was significantly inhibited by lysionotin. Lactate dehydrogenase and live/dead assays indicated that lysionotin effectively protected human alveolar epithelial cells against S. aureus, and in vivo studies also demonstrated that lysionotin can protect mice from pneumonia caused by S. aureus. These findings suggest that lysionotin is an efficient inhibitor of α-toxin expression and shows significant protection against S. aureus in vitro and in vivo. This study supports a potential strategy for the treatment of S. aureus infection by inhibiting the expression of virulence factors and indicates that lysionotin may be a potential treatment for S. aureus pneumonia.