NLRP3 Disturbs Treg/Th17 Cell Balance to Aggravate Apical Periodontitis

Apical periodontitis is an inflammatory condition that is considered an immunological reaction of the periapical tissue to invading bacteria and their pathogenic components. Recent research has revealed that NLR family pyrin domain containing 3 (NLRP3) is crucial to the pathogenesis of apical periodontitis and serves as a link between innate and adaptive immunity. The balance between regulatory T-cell (Treg) and T helper cell 17 (Th17 cell) determines the direction of the inflammatory response. Therefore, this study aimed to investigate whether NLRP3 exacerbated periapical inflammation by disturbing Treg/Th17 balance and the underlying regulatory mechanisms. In the present study, NLRP3 was raised in apical periodontitis tissues as opposed to healthy pulp tissues. Low NLRP3 expression in dendritic cells (DCs) increased transforming growth factor β secretion while decreasing interleukin (IL)-1β and IL-6 production. The Treg ratio and IL-10 secretion rose when CD4⁺ T cells were cocultured with DCs primed with IL-1β neutralizing antibody (anti-IL-1β) and specific small interfering RNA (siRNA) targeting NLRP3 (siRNA NLRP3), but the proportion of Th17 cells and IL-17 release dropped. Furthermore, siRNA NLRP3-mediated suppression of NLRP3 expression aided Treg differentiation and elevated Foxp3 expression as well as IL-10 production in CD4⁺ T cells. Inhibition of NLRP3 activity by MCC950 boosted the percentage of Tregs while decreasing the ratio of Th17 cells, leading to reduced periapical inflammation and bone resorption. Nigericin administration, however, exacerbated periapical inflammation and bone destruction with an unbalanced Treg/Th17 response. These findings demonstrate that NLRP3 is a pivotal regulator by regulating the release of inflammatory cytokines from DCs or directly suppressing Foxp3 expression to disturb Treg/Th17 balance, thus exacerbating apical periodontitis.

The long noncoding RNA LINC15957 regulates anthocyanin accumulation in radish

Radish (Raphanus sativus L.) is an important root vegetable crop belonging to the Brassicaceae family. Anthocyanin rich radish varieties are popular among consumers because of their bright color and high nutritional value. However, the underlying molecular mechanism responsible for skin and flesh induce anthocyanin biosynthesis in transient overexpression, gene silencing and transcriptome sequencing were used to verify its function in radish anthocyanin accumulation, radish remains unclear. Here, we identified a long noncoding RNA LINC15957, overexpression of LINC15957 was significantly increased anthocyanin accumulation in radish leaves, and the expression levels of structural genes related to anthocyanin biosynthesis were also significantly increased. Anthocyanin accumulation and expression levels of anthocyanin biosynthesis genes were significantly reduced in silenced LINC15957 flesh when compared with control. By the transcriptome sequencing of the overexpressed LINC15957 plants and the control, 5,772 differentially expressed genes were identified. A total of 3,849 differentially expressed transcription factors were identified, of which MYB, bHLH, WD40, bZIP, ERF, WRKY and MATE were detected and differentially expressed in the overexpressed LINC15957 plants. KEGG enrichment analysis revealed the genes were significant enriched in tyrosine, L-Phenylalanine, tryptophan, phenylpropanol, and flavonoid biosynthesis. RT-qPCR analysis showed that 8 differentially expressed genes (DEGs) were differentially expressed in LINC15957-overexpressed plants. These results suggested that LINC15957 involved in regulate anthocyanin accumulation and provide abundant data to investigate the genes regulate anthocyanin biosynthesis in radish.

Conductive materials as fantastic toolkits to stimulate direct interspecies electron transfer in anaerobic digestion: new insights into methanogenesis contribution, characterization technology, and downstream treatment

Direct interspecies electron transfer (DIET) stimulated by conductive materials (CMs) enables intercellular metabolic coupling that can address the unfavorable thermodynamical dilemma inherent in anaerobic digestion (AD). Although the DIET mechanism and stimulation have been extensively summarized, the methanogenesis contribution, characterization techniques, and downstream processes of CMs-led DIET in AD are surprisingly under-reviewed. Therefore, this review aimed to address these gaps. First, the contribution of CMs-led DIET to methanogenesis was re-evaluated by comparing the effect of various factors, including volatile fatty acids, free ammonia, and functional enzymes. It was revealed that AD systems are usually intricate and cannot allow the methanogenesis stimulation to be singularly attributed to the establishment of DIET. Additionally, considerable attention has been attached to the characterization of DIET occurrence, involving species identification, gene expression, electrical properties, cellular features, and syntrophic metabolism, suggesting the significance of accurate characterization methods for identifying the syntrophic metabolism interactions. Moreover, the type of CMs has a significant impact on AD downstream processes involving biogas purity, sludge dewaterability, and biosolids management. Finally, the central bottleneck consists in building a mathematical model of DIET to explain the mechanism of DIET in a deeper level from kinetics and thermodynamics.

Anticeramide Improves Sjögren's Syndrome by Blocking BMP6-Induced Th1

T-cell dysfunction has been shown to play an important role in the pathogenesis of Sjögren's syndrome (SS). In recent studies, the increased expression of BMP6 has been reported to be related to SS. However, the roles that BMP6 plays in immune homeostasis in the development of SS as well as the downstream signals activated by BMP6 remain unclear. In this study, we investigated the effects and molecular mechanisms of BMP6 on naive CD4⁺ T cells, showing that BMP6 could upregulate interferon (IFN)-γ secretion from CD4⁺ T cells through a ceramide/nuclear factor-κB pathway, with no effect on T-cell activation or proliferation. Moreover, an in vivo study showed that anticeramide treatment (myriocin) for an SS animal model (NOD/LtJ mice) could significantly decrease the IFN-γ expression and Th1 frequency in the salivary glands and suppress the inflammation infiltration in salivary glands and maintain the salivary flow rates, both of which reflect SS-like symptoms. This study identifies a promising target that could effectively attenuate the abnormal state of CD4⁺ T cells and reverse the progression of SS.

Association between Dried Fruit Intake and DNA Methylation: A Multivariable Mendelian Randomization Analysis

OBJECTIVES

Observational studies have reported associations between dried fruit intake and DNA methylation(DNAm). However, inherent flaws in observational study designs make them susceptible to confounding and reverse causality bias. Consequently, it is unclear whether a causal association exists. In the present study, we aimed to investigate the causal associations between dried fruit intake and DNAm.

METHODS

We performed two-sample Mendelian randomization (MR) using the IEU Open GWAS database aggregated data. Forty-three single nucleotide polymorphisms (SNPs) associated with dried fruit intake as instrumental variables (IVs) were selected as exposure. DNAm outcomes include Gran (estimated granulocyte proportions); AgeAccelGrim(GrimAge acceleration); Hannum (Hannum age acceleration); IEAA(Intrinsic epigenetic age acceleration), AgeAccelPheno( PhenoAge acceleration), and DNAmPAIadjAge (DNAm-estimated plasminogen activator inhibitor-1 levels). We used the MR pleiotropy residual sum and outlier test (MRPRESSO) and Radial-MR test to identify any level of multi-effect outliers and assessed the causal effect estimates(after removing outliers). The primary causal effects were estimated using inverse-variance weighted (IVW) method and undertook sensitivity analyses using MR methods robust to horizontal pleiotropy.The direct effects of dried fruit intake on DNAm were estimated using multivariable mendelian randomization (MVMR).

RESULTS

Leveraging two-sample MR analysis, we observed statistically significant associations between dried fruit intake with a lower AgeAccelGrim(β=-1.365, 95% confidence intervals [CI] -2.266 to -0.464, PIVW=2.985×10-3) and AgeAccelPheno (β= -1.933, 95% CI -3.068 to -0.798, PIVW=8.371×10-4). By contrast, the effects level on Gran (β=0.008, PIVW=0.430), Hannum(β=-0.430, PIVW=0.357), IEAA(β=-0.184, PIVW=0.700), and DNAmPAIadjAge (β=-1.861, PIVW=0.093) were not statistically significant. MVMR results adjusting for the potential effects of confounders showed that the causal relationship between dried fruit intake and AgeAccelGrim(β= -1.315, 95% CI -2.373 to -0.258, PIVW=1.480×10-2) and AgeAccelPheno(β= -1.595, 95% CI -2.987 to -0.202, PIVW=2.483×10-2) persisted. No significant horizontal polymorphism was found in the sensitivity analysis.

CONCLUSION

Our MR study suggested that increased dried fruit intake is associated with slower AgeAccelGrim and AgeAccelPheno. It can providing a promising avenue for exploring the beneficial effects of dried fruit intake on lifespan extension.

[Impact of late sodium current inhibition on cardiac electrophysiology parameters and ventricular arrhythmias in isolated Langendorff perfused rabbit hearts with short QT interval]

Objective: To determine the electrophysiological effects and related mechanisms of late sodium current inhibitors on hearts with short QT intervals. Methods: The electrophysiological study was performed on isolated Langendorff perfused rabbit hearts. A total of 80 New Zealand White rabbits were used and 34 hearts without drug treatment were defined as control group A, these hearts were then treated with I_KATP opener pinacidil, defined as pinacidil group A. Then, 27 hearts from pinacidil group A were selected to receive combined perfusion with sodium channel inhibitors or quinidine, a traditional drug used to treat short QT syndrome, including ranolazine combined group (n=9), mexiletine combined group (n=9), and quinidine combined group (n=9). Nineteen out of the remaining 46 New Zealand rabbits were selected as control group B (no drug treatments, n=19), and then treated with pinacidil, defined as pinacidil group B (n=19). The remaining 27 rabbits were treated with sodium inhibitors or quinidine alone, including ranolazine alone group (n=9), mexiletine alone group (n=9), and quinidine alone group (n=9). Electrocardiogram (ECG) physiological parameters of control group A and pinacidil group A were collected. In control group B and pinacidil group B, programmed electrical stimulation was used to induce ventricular arrhythmias and ECG was collected. ECG physiological parameters and ventricular arrhythmia status of various groups were analyzed. The concentrations of pinacidil, ranolazine, mexiletine and quinidine used in this study were 30, 10, 30 and 1 μmol/L, respectively. Results: Compared with control group A, the QT interval, 90% of the repolarization in epicardial and endocardial monophasic action potential duration (MAPD₉₀-Epi, MAPD₉₀-Endo) was shortened, the transmural dispersion of repolarization (TDR) was increased, and the effective refractor period (ERP) and post-repolarization refractoriness (PRR) were reduced in pinacidil group A (all P<0.05). Compared with the pinacidil group A, MAPD₉₀-Epi, MAPD₉₀-Endo, QT interval changes were reversed in quinidine combined group and mexiletine combined group (all P<0.05), but not in ranolazine combined group. All these three drugs reversed the pinacidil-induced increases of TDR and the decreases of ERP and PRR. The induced ventricular arrhythmia rate was 0 in control group B, and increased to 10/19 (χ²=13.6, P<0.05) in pinacidil group B during programmed electrical stimulation. Compared with the pinacidil group B, incidences of ventricular arrhythmia decreased to 11% (1/9), 11% (1/9) and 0 (0/9) (χ²=4.5, 4.5, 7.4, P<0.05) respectively in ranolazine group, mexiletine group and quinidine group. Conclusions: Inhibition of late sodium current does not increase but even decreases the risk of malignant arrhythmia in hearts with a shortened QT interval. The antiarrhythmic mechanism might be associated with the reversal of the increase of TDR and the decrease of refractoriness (including both ERP and PRR) of hearts with shortened QT interval.

Morusin Protected Ruminal Epithelial Cells against Lipopolysaccharide-Induced Inflammation through Inhibiting EGFR-AKT/NF-κB Signaling and Improving Barrier Functions

Using phytogenic extracts for preventing or treating rumen epithelial inflammatory injury is a potential alternative to antibiotic use due to their residue-free characteristics. In this study, the efficacy of Morus root bark extract Morusin on ruminal epithelial cells (RECs) against pathogenic stimulus was investigated for the first time. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and quantitative real-time polymerase chain reaction (qPCR) results showed that the Morusin did not affect the cell viability of RECs and exerted anti-inflammatory effects in a concentration-dependent manner. Transcriptome analysis further revealed that the Morusin significantly downregulated the inflammatory-response-related cell signaling, while it upregulated the cell-proliferation-inhibition- and barrier-function-related processes in RECs upon lipopolysaccharide (LPS) stimulation. The epidermal growth factor receptor (EGFR) blocking and immunoblotting analysis further confirmed that the Morusin suppressed LPS-induced inflammation in RECs by downregulating the phosphorylation of protein kinase B (AKT) and nuclear factor-kappaB (NF-κB) p65 protein via inhibiting the EGFR signaling. These findings demonstrate the protective roles of Morusin in LPS-induced inflammation in RECs.

Impact of surgical left atrial appendage closure during coronary bypass on clinical outcomes and readmissions

Background

Whether surgical left atrial appendage closure (sLAAC) during coronary artery bypass (CABG)surgery improves post-operative outcome including stroke and atrial fibrillation (AF) occurrence is largely unknown.

Objective

To analyze the impact of concomitant sLAAC during CABG in terms of outcomes and readmissions over the following year.

Methods

We analyzed the Nationwide Readmissions Database (2016–2019) using ICD-10 codes to identify hospitalizations for CABG. Patients were subcategorized based on whether sLAAC was performed or not. Among patients who survived their index admission, we employed propensity matching (1:3) to adjust for age, sex, comorbidities, CHA2DS2-VASc scores, previous AF history, heart failure and hospital characteristics. Primary outcomes included unplanned AF and stroke-related readmissions at 1 year.

Results

A total of 58,311 patients with CABG and sLAAC were identified with 175,940 propensity matched controls. Patients undergoing sLAAC were older with higher CHA2DS2-VASc scores and comorbidity burdens. Confounders were well balanced following propensity matching. Over a mean follow-up of 152 days, sLAAC was associated with higher risk of readmission due to AF at one year (HR 1.71 [1.49–1.96] p&lt;0.001). This association is independent of previous AF history. Lower rates of stroke-related readmission was associated with perfomance of sLAAC (HR 0.80 (0.65–0.97) p=0.026), however the association was not observed when accounting for AF history.

Conclusion

CABG with concomitant sLAAC is maybe associated with lower stroke risk at the cost of higher risk of AF readmissions.

Funding Acknowledgement

Type of funding sources: None.

Bio-distribution and longevity of mesenchymal stromal cell derived membrane particles

Vesicle-based medicines hold great promise for therapy development but essential knowledge on the bio-distribution and longevity of vesicles after administration is lacking. We generated vesicles from the membranes of human mesenchymal stromal cells (MSC) and we demonstrated earlier that these so-called membrane particles (MP) mediate immunomodulatory and regenerative responses in target cells. In the present study we examined the bio-distribution and longevity of MP after intravenous administration in mice. While most vesicle tracking methods are based on imaging techniques, which require labeling of vesicles and can only detect dense accumulations of vesicles, we used proteomics analysis to detect the presence of MP-derived proteins in multiple organs and tissues. MP proteins were mainly present in plasma and leukocytes at 1 h after injection, indicating that MP - in contrast to whole MSC - do not accumulate in the lungs upon first passage but remain in circulation. After 24 h, MP proteins were still present in plasma but were most abundant in the liver. RNA sequencing of livers demonstrated that MP impact liver function and in particular induce metabolic pathways. These data provide a clear view of the bio-distribution and longevity of MP, which is likely extrapolatable to other types of vesicles, and demonstrate that MP circulate for up to 24 h and may be a tool for targeting the liver.

JS09.5.A Is Radiation Dose to Sleep-relevant Brain Structures Associated with Lower Sleep Quality in Adults with Primary Brain Tumors?

Background

Sleep plays a central role in optimal brain health and daily functioning, and poor sleep is associated with impaired cognitive functioning and reduced quality of life. Despite improved precision of modern radiotherapy (RT) for brain tumors, radiation to healthy tissue, including brain structures relevant for sleep/wake regulation, is often inevitable. In the present study, we investigate whether radiation dose to sleep/wake-relevant brain structures is associated with poorer patient-reported sleep quality in primary brain tumor patients.

Material and Methods

Patients who had received RT for non-glioblastoma primary brain tumors between 2006 and 2016 were included. They completed the Pittsburg Sleep Quality Index (PSQI) and mean radiation doses to sleep/wake-relevant structures (i.e., brainstem, thalamus, hypothalamus, and the pituitary and pineal glands) were calculated based on planning CTs and contrast-enhanced MR-images. Mean radiation dose (Dmean) to brain structures were compared between patients with and without impaired sleep outcomes using bootstrapped independent t-tests. Differences with effect sizes (ES, Cohen’s d) exceeding ± 0.3 are reported.

Results

A total of 78 patients (glioma, grade 1-3 = 28; meningioma = 22, pituitary = 16, other = 12) were included. Median time since RT was 4.6 years (range = 8.4 years). Mean global PSQI score was 5.13 (SD = 3.1). No differences were observed between tumor types, F (3,74) = 0.37, η 2= .02. Clinical sleep disturbance (PSQI &gt; 5) was reported by 37.2% (n=29). Compared with patients without sleep disturbance, those with sleep disturbance had received a higher radiation dose to the pituitary gland, Dmean = 26.11 Gy, SE = 2.59, versus 34.57 Gy, SE = 3.43, ES(d) = - 0.46, 95% CI [-0.93, 0.003]. Furthermore, compared with patients reporting normal sleep latency (SL), those with poor SL had received a higher radiation dose to the pituitary gland, Dmean = 24.55 Gy, SE = 3.71, versus 32.60 Gy, SE = 2.48, ES(d) = - 0.44, 95% CI [-0.90, 0.03], and the brain stem, Dmean = 15.32 Gy, SE = 2.71, versus 20.20 Gy, SE = 2.01, ES(d) = -3.44, 95% CI [-0.80, 0.12]. Finally, compared with patients with a high sleep efficiency (&gt;85%), those with a low sleep efficiency had received a higher radiation dose to the thalamus, Dmean = 18.11 Gy, SE = 2.36, versus 24.55 Gy, SE = 4.43, ES(d) = -0.35, 95% CI [-0.83, 0.15], and the pineal gland, Dmean = 16.20 Gy, SE = 2.48, versus 23.10 Gy, SE = 4.25, ES(d) = -0.36, 95% CI [-0.85, 0.13].

Conclusion

The prevalence of clinical sleep disturbances in patients with primary brain tumors was high (37%). Our results indicated that higher radiation doses to the pituitary gland, brain stem, thalamus, and pineal gland may be risk factors for poor sleep quality in patients with a primary brain tumor.