Exosome from BMMSC Attenuates Cardiopulmonary Bypass-Induced Acute Lung Injury Via YAP/ß-Catenin Pathway: Downregulation of Pyroptosis.

Acute lung injury (ALI) accompanied with systemic inflammatory response is an important complication after cardiopulmonary bypass (CPB). Pyroptosis, which is induced by the secretion of inflammatory factors, has been implicated in ALI. However, recent studies have suggested that bone marrow mesenchymal stem cell-derived exosomes (BMMSC-Exo) can ameliorate ALI, but the mechanism is poorly understood. Therefore, we aim to examine the effects of BMMSC-Exo in CPB-induced ALI, and its underlying mechanism. CPB rat models (male Sprague-Dawley rats) were administered BMMSC-Exo intravenously before induction of ALI. Lung tissue, bronchoalveolar lavage fluid (BALF), and alveolar macrophage (AM) were collected after the treatments for further analysis, and rat AM NR8383 cells were used for in vitro study. HE staining was performed to detect macrophage infiltration. Western blot was used to detect related proteins expression. And ELISA assay was performed to investigate secretion of inflammatory factors. These results showed that BMMSC-Exo treatment ameliorated macrophage infiltration and oxidative stress, and downregulated expression of pyroptosis-related proteins, including NLRP3, cleaved caspase-1, and GSDMD-N, in the lung tissue and AM, as well as decreased the secretion of IL-18 and IL-1ß in BALF. Moreover, BMMSC-Exo activated YAP/ß-catenin signaling pathway. Overall, these findings of this study indicated that BMMSC-Exo suppressed CPB-induced pyroptosis in ALI by activating YAP/ß-catenin axis, which could be a novel strategy for lung protection during CPB.

Association of intraoperative cerebral and somatic tissue oxygen saturation with postoperative acute kidney injury in adult patients undergoing multiple valve surgery.

BACKGROUND: The association between tissue oxygenation with postoperative acute kidney injury (AKI) in adult patients undergoing multiple valve surgery has not been specifically studied. METHODS: In this prospective exploratory cohort study, 99 patients were enrolled. The left forehead, the left forearm, the left upper thigh, and the left renal region tissue oxygen saturation using near-infrared spectroscopy were monitored. The association between each threshold and AKI was assessed. The relative and absolute thresholds were < 70%, < 75%, < 80%, < 85%, < 90%, < 95%, and < 100% baseline, and baseline-standard deviation (SD), -1.5 SD, -2 SD, -2.5 SD, and -3 SD. Multivariate logistic regression analysis was adopted to explore the association. RESULTS: AKI occurred in 53 (54%) patients. The absolute value-based SrrO2 thresholds associated with AKI were baseline-3 SD (odds ratio [OR], 4.629; 95% confidence interval [CI], 1.238-17.314; P = 0.023) and baseline-2.5 SD (OR, 2.842; 95% CI, 1.025-7.881; P = 0.045) after adjusting for the potential confounders, those are renal region tissue oxygen saturation of 55% and 60%, but not statistically significant after correcting for multiple testing (corrected P = 0.114 and 0.179, respectively). CONCLUSION: The SrrO2 desaturation, defined as < baseline - 2.5 SD or < baseline - 3 SD, may be associated with AKI. The thresholds need to be verified in future large-scale studies. TRIAL REGISTRATIONS: The study was registered at ClinicalTrials.gov, first trial registration: 26/10/2017, identifier: NCT03323203.

Genes related to neurotransmitter receptors as potential biomarkers for Alzheimer's disease.

INTRODUCTION: Alzheimer's disease (AD) is a leading cause of dementia and is rapidly emerging as one of the costliest and most burdensome diseases. Neurotransmitter receptors play a vital role in many neuronal processes, primarily regulating signal inhibition within the brain to facilitate cell communication. OBJECTIVES: Our research aims to identify potential biomarkers associated with AD and how these biomarkers impact immune infiltration. METHODS: We extracted mRNA expression data from the Gene Expression Omnibus (GEO) database. Weighted gene co-expression network analysis (WGCNA) and differential expression analysis were employed to identify hub genes as biomarkers in AD. The Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and Gene Set Variation Analysis (GSVA) were used for functional enrichment. Furthermore, we examined 22 immune cell types infiltration using "CIBERSORT". RESULTS: In this study, we identified 70 neurotransmitter receptor genes showing differential expression in AD: 22 were up-regulated, and 48 were down-regulated. Functional analyses indicated these genes were involved in essential biochemical pathways, including G protein-coupled receptors, neurotransmitter receptor activity, and ion channel interactions. WGCNA generated three co-expression modules, with one demonstrating the strongest association with AD. Five key NRGs (HTR3C, HTR3E, ADRA2A, HTR3A, and ADRA1D) were identified using a combination of differential genes. These genes have better diagnostic value by ROC analysis. Immune infiltration analysis showed that these genes were closely associated with the levels of resting mast cells, activated natural killer (NK) cells, and plasma cells in AD compared to controls. CONCLUSION: Our study identified five NRGs (ADRA1D, ADRA2A, HTR3A, HTR3C, and HTR3E) with significant associations with AD. These findings may offer promising sights for further studies.

Irisin-pretreated BMMSCs Secrete Exosomes to Alleviate Cardiomyocytes Pyroptosis and Oxidative Stress to Hypoxia/reoxygenation Injury.

BACKGROUND: The cardiomyocytes pyroptosis and bone marrow-derived mesenchymal stem cells have been well considered as novel therapies to attenuate myocardial ischemia/reperfusion injury, however, the relationship has not yet been determined. OBJECTIVE: We aim to evaluate whether pre-treatment bone marrow-derived mesenchymal stem cells protect against myocardial ischemia/reperfusion injury by repressing cardiomyocytes pyroptosis, as well as to further elucidate the potential mechanisms. METHODS: Cardiomyocytes were treated with hypoxia, followed by reoxygenation to mimic myocardial ischemia/reperfusion injury. Pre-treatment bone marrow-derived mesenchymal stem cells or their exosomes were co-cultured with cardiomyocytes following hypoxia/reoxygenation. Cell Counting Kit-8 assay was used to determine cell viability. Reactive oxygen species production was determined by dihydroethidium stain. Enzyme-linked immunosorbent assays were used to detect IL-1ß and IL-18. RESULTS: We observed that Irisin pre-treatment bone marrow-derived mesenchymal stem cells protected cardiomyocytes against hypoxia/reoxygenation-induced injuries. The underlying molecular mechanism was further identified. Irisin-BMMSCs were found to secrete exosomes, which repressed cardiomyocytes pyroptosis and oxidative stress response by suppressing NLRP3 under hypoxia/reoxygenation conditions. CONCLUSION: Based on our findings, we revealed a promising target that exosomes derived from bone marrow-derived mesenchymal stem cells with Irisin treatment to elevate the therapeutic benefits for hypoxia/ reoxygenation injury.

BMMSC-derived Exosomes Attenuate Cardiopulmonary Bypass-related Acute Lung Injury by Reducing Inflammatory Response and Oxidative Stress.

BACKGROUND: Acute lung injury (ALI), which is characterized by inflammation and oxidative stress, is a common complication after cardiopulmonary bypass (CPB). Exosomes from bone marrow mesenchymal stem cells (BMMSC-Exo) have recently been identified as promising treatments for ALI. However, the effects of BMMSC-Exo on inflammation and oxidative stress in CPB-related ALI remain unclear. OBJECTIVE: We aim to evaluate the effects of BMMSC-Exo on post-CPB ALI and explore their potential mechanisms. METHODS: We randomly divided rats into three groups: sham, ALI, and ALI+BMMSC-Exo groups. Histological changes were evaluated by lung histo-pathology and bronchoalveolar lavage fluid (BALF). ELISA assay was used to determine inflammatory cytokine levels and oxidative stress. RESULTS AND DISCUSSION: BMMSC-Exo attenuated histological changes (including the invasion of inflammatory cells), reduced the wet/dry (W/D) weight ratio, and downregulated inflammatory cytokine levels, including tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, and IL-1ß. BMMSC-Exo also alleviated oxidative stress. In vitro, we further administered lipopolysaccharide (LPS) to alveolar macrophages (AMs) to mimic the pathological changes of ALI and found that BMMSC-Exo suppressed reactive oxygen species (ROS) production and downregulated the levels of inflammatory cytokines. Mechanistically, BMMSC-Exo inhibited the phosphorylation of nuclear factor-κB (NF-κB), the nuclear translocation of p65, also facilitated the phosphorylation of Akt and the nuclear translocation of Nrf2, while upregulating the expression of HO-1. CONCLUSION: In summary, we indicate that BMMSC-Exo reduces CPB-related ALI by alleviating inflammation and oxidative stress. The underlying mechanism may involve the NF-κB p65 and Akt/Nrf2/HO-1 signaling pathways.

Time-restricted feeding alleviates metabolic implications of circadian disruption by regulating gut hormone release and brown fat activation.

Individuals with rotating and night shift work are highly susceptible to developing metabolic disorders such as obesity and diabetes. This is primarily attributed to disruptions in the circadian rhythms caused by activities and irregular eating habits. Time-restricted feeding (tRF) limits the daily eating schedules and has been demonstrated to markedly improve several metabolic disorders. Although an intricate relationship exists between tRF and circadian rhythms, the underlying specific mechanism remains elusive. We used a sleep disruption device for activity interference and established a model of circadian rhythm disorder in mice with different genetic backgrounds. We found that circadian rhythm disruption led to abnormal hormone secretion in the gut and elevated insulin resistance. tRF improved metabolic abnormalities caused by circadian rhythm disruption, primarily by restoring the gut hormone secretion rhythm and activating brown fat thermogenesis. The crucial function of brown fat in tRF was confirmed using a mouse model with brown fat removal. We demonstrated that chenodeoxycholic acid (CDCA) effectively improved circadian rhythm disruption-induced metabolic disorders by restoring brown fat activation. Our findings demonstrate the potential benefits of CDCA in reversing metabolic disadvantages associated with irregular circadian rhythms.

Mediator complex subunit 8 is a prognostic biomarker in hepatocellular carcinoma.

BACKGROUND: Mediator complex subunit 8 (MED8) is known for its role in encoding a subunit of the mediator complex (MED), that is critical for transcription. MED8 is significantly expressed in various tumors and has been correlated with an unfavorable prognosis. Nevertheless, no relationships have been found between MED8 and the clinical characteristics of hepatocellular carcinoma (HCC). METHODS: To conduct an evaluation of correlations between clinicopathologic characteristics and MED8 expression, the logistic regression, Wilcoxon signed-rank test, and Kruskal-Wallis test were used. To perform analysis of factors contributing to prognosis, the Kaplan-Meier approach and the Cox regression analyses were used. A nomogram on the basis of a Cox multivariate analysis was employed to anticipate the influence of MED8 on patient prognosis. The receiver operating characteristic (ROC) curves were plotted and the areas under the curve (AUC) were calculated to assess the prognostic value of MED8. Both immune infiltration analysis and Gene Set Enrichment Analysis (GSEA) were applied to reveal significant enrichment differences among TCGA data. Quantitative RT-PCR (qRT-PCR) and western blotting were used to verify the difference in the expression of MED8 in normal and hepatocellular carcinoma cells. The immunohistochemical method was used to validate the MED8 expression in tumor and adjoining tissues of HCC patients. RESULTS: A univariate analysis showed that high MED8 expression predicts poor disease-specific survival (DSS) (HR: 2.57; 95% confidence interval (CI) 1.62, 4.07; P<0.001). Multivariate regression analysis showed that high MED8 (adjusted HR: 3.032 (1.817, 5.060); P<0.001) expression and M stage (adjusted HR=4.075 (1.179-14.091) for M1 vs. M0, P=0.026) served as prognostic indicators of unfavorable overall survival in an independent manner in patients with HCC. The C-index for the nomogram was 0.732 (95% CI: 0.698, 0.766) and the AUC of MED8 was 0.817 (95% CI: 0.778, 0.857). Functional analysis showed that the cell cycle checkpoints, p53 dependent G1-DNA damage response, mitotic G1-G1-S phases, and mitotic G2-G2-M phases, were significantly enriched in DEGs associated with MED8 expression. Th2 cells were positively correlated with MED8 expression. CONCLUSIONS: MED8 predicts poor prognosis in HCC, possibly through modulating the cell cycle and Th2 cells.

Glucuronoxylomannan promotes the generation of antigen-specific T regulatory cell that suppresses the antigen-specific Th2 response upon activation.

T regulatory cells (Treg) have the capability to suppress the skewed immune response, but the generation of antigen (Ag)-specific Treg for therapeutic purpose is a challenge; the mechanism of Ag-specific Treg activation remains obscure. Here, we report that glucuronoxylomannan (GXM) is capable of promoting the development of human tolerogenic dendritic cells (DC). GXM-pulsed DCs increased the expression of forkhead box P3 (Foxp3) in naïve human CD4(+)CD25(-) T cells via activating Fc gamma receptor IIb and activator protein-1 and promoting the expression of transforming growth factor beta in dendritic cells. Furthermore, the conjugated complex of house dust mite Ag, Dermatophagoides pteronyssinus (Der p) 1, and GXM-pulsed DCs to drive the naïve human CD4(+)CD25(-) T cells to develop into the Der p 1-specific Tregs, which efficiently suppressed the Ag-specific Th2 responses. We conclude that GXM-conjugated specific Ag have the capacity to up-regulate the tolerogenic property of DCs and promote the generation of Ag-specific Tregs; the latter can be activated upon the re-exposure to specific Ag and suppress the skewed Ag-specific T helper (Th)2 responses.

Staphylococcal enterotoxin B increases TIM4 expression in human dendritic cells that drives naïve CD4 T cells to differentiate into Th2 cells.

Aberrant T helper (Th)2 polarization plays a critical role in the pathogenesis of allergic disorders; the etiology remains unclear. Dendritic cells (DCs) express T cell immunoglobulin mucin domain (TIM)4 that ligates TIM1 on CD4 T cells to drive them to become Th2 cells, but the pathogenic source of TIM4 is unknown. Here we report that a significant increase in TIM4 expression in human DCs was observed in response to Staphylococcal enterotoxin B (SEB) stimulation via Toll-like receptor (TLR)2 and nucleotide-binding oligomerization domain (NOD)1 pathway. Coculture SEB-conditioned DCs with naïve CD4 T cells induced Th2 responses that could be abolished using TLR2 or NOD1 or TIM4 or TIM1 with counterpart antibodies or RNA interference. The results demonstrate that Staphylococcus aureus derived SEB promotes the TIM4 production in human DCs. The interaction between TIM4 and TIM1 drives naïve CD4 T cells to develop to Th2 cells.

Rhinosinusitis derived Staphylococcal enterotoxin B possibly associates with pathogenesis of ulcerative colitis.

BACKGROUND: During clinical practice, we noticed that some patients with both ulcerative colitis (UC) and chronic rhinosinusitis (CRS) showed amelioration of UC after treatment of CRS. This study was designed to identify a possible association between CRS and UC. METHODS: Thirty-two patients with both CRS and UC received treatment with functional endoscopic sinus surgery (FESS) for CRS. Clinical symptom scores for CRS and UC, as well as serum levels of anti-Staphylococcal enterotoxin B (SEB) were evaluated at week 0 and week 12. Sinus wash fluid SEB content was measured with enzyme-linked immunosorbent assay (ELISA). The surgically removed tissues were cultured to identify growth of Staphylococcus. aureus (S. aureus). Immunohistochemistry was employed to identify anti-SEB positive cells in the colonic mucosa. Colonic biopsies were obtained and incubated with SEB. Mast cell activation in the colonic mucosa in response to incubation with SEB was observed with electron microscopy and immunoassay. RESULTS: The clinical symptom scores of CRS and UC severe scores (UCSS) were significantly reduced in the UC-CRS patients after FESS. The number of cultured S. aureus colonies from the surgically removed sinus mucosa significantly correlated with the decrease in UCSS. High levels of SEB were detected in the sinus wash fluids of the patients with UC-CRS. Histamine and tryptase release was significantly higher in the culture supernate in the patients with UC-CRS than the patients with UC-only and normal controls. Anti-SEB positive cells were located in the colonic mucosa. CONCLUSION: The pathogenesis of UC in some patients may be associated with their pre-existing CRS by a mechanism of swallowing sinusitis-derived SEB. We speculate that SEB initiates inappropriate immune reactions and inflammation in the colonic mucosa that further progresses to UC.

[Expression and significance of PTEN and HIF-1α proteins in sinonasal inverted papilloma].

OBJECTIVE: To investigate the expression and clinical significance of phosphatase and tensin homology deleted on chromosome ten (PTEN) and hypoxia-inducible factor 1 alpha (HIF-1α) in sinonasal inverted papilloma (SNIP) of different pathological grades. METHODS: Fifty-five paraffin samples from patients with SNIP and a control group of 10 paraffin samples of patients with normal nasal cavity mucosa (NM) who underwent inferior turbinectomy were consisted in this study. Among the 55 cases of SNIP, 30 cases were without dysplasia subtypes, 11 cases were with dysplasia subtypes, and 14 cases with canceration to squamous cell carcinoma (SCC) subtypes. PTEN and HIF-1α expression in SNIP was detected by immunohistochemistry. The differences between NM and SNIP, and among the three subtypes were analyzed, and the relationship between PTEN, HIF-1α expression and SNIP recurrence and the correlation between PTEN expression and HIF-1α expression were also analyzed. SPSS 16.0 software was used to analyze the data. RESULTS: The positive expression rate of PTEN in NM and SNIP was 100% and 65.5%, the difference was significant (U = 147, P = 0.014), while HIF-1α was 0 and 30.9%, the difference was significant (U = 190, P = 0.045). The positive expression rate of PTEN in SNIP without dysplasia, SNIP with dysplasia and NSCC was 83.3%, 63.6%, 28.6%, respectively, the difference was significant (H = 12.644, P = 0.002); while HIF-1α was 16.7%, 45.5%, 50.0%, respectively, the difference was significant (H = 8.292, P = 0.016). A total of 22 SNIP patients recurred. PTEN had lower expression in recurrent SNIP (45.5%) than that in non-recurrent SNIP (82.8%), and the difference was significant(χ² = 7.834, P = 0.005). However, the expression of HIF-1α had no significant difference between recurrent SNIP and the SNIP which had no recurrence (χ² = 0.901, P = 0.343). The expression of PTEN protein was negatively correlated with that of HIF-1α protein (r = -0.503, P = 0.001). CONCLUSIONS: PTEN expression decreased graduately with the severity of malignancy of SNIP, but HIF-1α increased. The expression of HIF-1α was induced by hypoxia, which may negatively effect the expression of PTEN, and both HIF-1α and PTEN may play critical roles in the progress of SNIP. PTEN is one of the factors responsible for the postoperative recurrence of SNIP.