Noncanonical contribution of microglial transcription factor NR4A1 to post-stroke recovery through TNF mRNA destabilization.

Microglia-mediated neuroinflammation is involved in various neurological diseases, including ischemic stroke, but the endogenous mechanisms preventing unstrained inflammation is still unclear. The anti-inflammatory role of transcription factor nuclear receptor subfamily 4 group A member 1 (NR4A1) in macrophages and microglia has previously been identified. However, the endogenous mechanisms that how NR4A1 restricts unstrained inflammation remain elusive. Here, we observed that NR4A1 is up-regulated in the cytoplasm of activated microglia and localizes to processing bodies (P-bodies). In addition, we found that cytoplasmic NR4A1 functions as an RNA-binding protein (RBP) that directly binds and destabilizes Tnf mRNA in an N6-methyladenosine (m6A)-dependent manner. Remarkably, conditional microglial deletion of Nr4a1 elevates Tnf expression and worsens outcomes in a mouse model of ischemic stroke, in which case NR4A1 expression is significantly induced in the cytoplasm of microglia. Thus, our study illustrates a novel mechanism that NR4A1 posttranscriptionally regulates Tnf expression in microglia and determines stroke outcomes.

A novel starch-active lytic polysaccharide monooxygenase discovered with bioinformatics screening and its application in textile desizing.

BACKGROUND: Lytic polysaccharide monooxygenases (LPMOs) catalyzing the oxidative cleavage of different types of polysaccharides have potential to be used in various industries. However, AA13 family LPMOs which specifically catalyze starch substrates have relatively less members than AA9 and AA10 families to limit their application range. Amylase has been used in enzymatic desizing treatment of cotton fabric for semicentury which urgently need for new assistant enzymes to improve reaction efficiency and reduce cost so as to promote their application in the textile industry. RESULTS: A total of 380 unannotated new genes which probably encode AA13 family LPMOs were discovered by the Hidden Markov model scanning in this study. Ten of them have been successfully heterologous overexpressed. AlLPMO13 with the highest activity has been purified and determined its optimum pH and temperature as pH 5.0 and 50 °C. It also showed various oxidative activities on different substrates (modified corn starch > amylose > amylopectin > corn starch). The results of enzymatic textile desizing application showed that the best combination of amylase (5 g/L), AlLPMO13 (5 mg/L), and H2O2 (3 g/L) made the desizing level and the capillary effects increased by 3 grades and more than 20%, respectively, compared with the results treated by only amylase. CONCLUSION: The Hidden Markov model constructed basing on 34 AA13 family LPMOs was proved to be a valid bioinformatics tool for discovering novel starch-active LPMOs. The novel enzyme AlLPMO13 has strong development potential in the enzymatic textile industry both concerning on economy and on application effect.

Systematic review and meta-analysis of stroke and thromboembolism risk in atrial fibrillation with preserved vs. reduced ejection fraction heart failure.

BACKGROUND: Stroke and thromboembolism (TE) are significant complications in patients with atrial fibrillation (AF) and heart failure (HF). The impact of ejection fraction status on these risks remains unclear. This study aims to compare the risk of stroke and TE in patients with AF and HF with preserved (HFpEF) or reduced (HFrEF) ejection fraction. METHODS: Literature search of PubMed, Embase, and Scopus databases was done for studies in adult (20 years or more) population of AF patients. Included studies had reported on the incidences of stroke and/or TE in patients with AF and associated HF with reduced ejection fraction (HFrEF) and preserved ejection fraction (HFpEF). Cohort (prospective and retrospective), case-control studies, and studies that were based on secondary analysis of data from a trial were eligible for inclusion. Methodological quality was assessed using the Newcastle Ottawa Scale (NOS). Pooled hazard ratio (HR) with 95% confidence intervals (CI) were reported. Exploratory analysis was conducted based on the different cut-offs used to define HFrEF and HFpEF. RESULTS: Twenty studies were analyzed. In the overall analysis, HFrEF in AF patients was associated with a significantly reduced risk of stroke and systemic TE (HR 0.88, 95% CI: 0.81, 0.96; n = 20, I2 = 86.6%), compared to HFpEF. However, most studies showed comparable risk of stroke among the two groups of patients except for two studies that had documented significantly reduced risk. Upon doing the sensitivity analysis by excluding these two studies, we found similar risk among the two group of subjects and with no heterogeneity (HR 1.01, 95% CI: 0.99, 1.03; n = 18, I2 = 0.0%). Exploratory analysis also showed that the risk of stroke and systemic thromboembolism was similar between those with HFpEF and HFrEF. CONCLUSION: The findings suggest that there is no significantly different risk of stroke and systemic thromboembolism in cases of AF with associated HFpEF or HFrEF. The finding does not support integration of left ventricular ejection fraction into stroke risk assessments.

The association between urine ketone and new-onset atrial fibrillation in critically ill patients.

BACKGROUND AND AIMS: New-onset atrial fibrillation (NOAF) is a common manifestation in critically ill patients. There is a paucity of evidence indicating a relationship between urinary ketones and NOAF. METHODS: Critically ill patients with urinary ketone measurements from the Medical Information Mart for Intensive Care (MIMIC-IV) database were included. The primary outcome was NOAF Propensity score matching was performed following by multivariable logistic regression. RESULTS: A total of 24,688 patients with available data of urine ketone were included in this study. The urine ketone of 4014 patients was tested positive. The average age of the included participants was 63.8 years old, and 54.5% of them were male. Result of the fully-adjusted binary logistic regression model showed that patients with positive urinary ketone was associated with a significantly lower risk of NOAF (Odds ratio, 0.79, 95% CI 0.7-0.9), compared with those with negative urinary ketone. In the subgroup analysis according to diabetic status, compared with nondiabetics, patients with diabetes had lower risk of NOAF (p-values for interaction < 0.05). Results of other subgroup analyses according to gender, age, infection, myocardial infarction, and congestive heart failure were consistent with the primary analysis. CONCLUSIONS: Positive urinary ketone body may be associated with reduced risk of NOAF in critically ill patients during intensive care unit hospitalization. Further studies are needed to clarify the underlying mechanisms.

A Prediction Model for Clinical Outcomes of COVID-19 Hospitalized Patients: Construction and Accuracy Assessment.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic spread rapidly with considerable morbidity nationwide since China's liberalization in December 2022. Our work has focused on identifying different predictive factors from the laboratory examination of critically ill patients, and forecasting the unfavorable outcome of critically ill patients with COVID-19 through a combined diagnosis of biological markers. METHODS: We conducted a retrospective study at the Department of First Affiliated Hospital of Wenzhou Medical University, China, from December 24, 2022, to January 10, 2023, where 434 critically ill patients who met the inclusion criteria were involved. Machine analysis was employed to search for the parameters with the highest predictive value to calculate COVID-19 mortality by exploiting 66 typical laboratory results. RESULTS: Combined diagnosis of serum albumin (ALB), lactate dehydrogenase (LDH), direct bilirubin (Dbil), ferritin, pulse oxygen saturation (SpO2), and neutrophil count (NEUT#) was evaluated, and the result with the highest predictive value (NEUT#) was selected as the predictor for COVID-19 mortality with a sensitivity of 89.2% and a specificity of 77.4%. CONCLUSIONS: The increased levels of LDH, Dbil, ferritin, and NEUT#, along with lowered ALB and SpO2 levels are the most decisive variables for forecasting the mortality for COVID-19 according to our machine-learning-based model. The combined diagnosis could be used to improve further diagnostic performance.

Bisphenol A (BPA) induces apoptosis of mouse Leydig cells via oxidative stress.

As one of the most frequently produced synthetic compounds worldwide, bisphenol A (BPA) has been widely used in many kinds of products such as appliances, housewares, and beverage cans. BPA has been shown to cause damage to male reproductive system; however, the potential mechanism remains to be investigated. In the present study, BPA exposure decreased the testis and epididymis coefficient, caused a disintegration of germinal epithelium, decreased the density and motility of sperm in the epididymis tissue, and increased the number of abnormal sperm morphology, which indicated that BPA exposure could cause damage to testis. BPA was also shown to induce apoptosis and oxidative stress in the testis tissue. The serum testosterone concentration was decreased in the BPA-treated group, suggesting that BPA could lead to Leydig cell damage. Subsequently, mouse TM3 cell, a kind of mouse Leydig cell line, was utilized to investigate the potential mechanism. Herein, we showed that BPA exposure could inhibit cell viability and induce apoptosis of TM3 cells. Furthermore, oxidative stress in the cells could also be induced by BPA, while the inhibition of oxidative stress by N-acetyl-L-cysteine (NAC), an oxidative stress scavenger, could reverse the inhibition of cell viability and induction of apoptosis by BPA exposure, indicating that oxidative stress was involved in BPA-induced apoptosis of TM3 cells. Finally, RNA-sequencing and real-time PCR were utilized to screen and validate the potential oxidative stress-related genes involving in BPA-induced apoptosis. We found that BPA exposure increased the mRNA levels of oxidative stress-related genes such as Lonp1, Klf4, Rack1, Egln1, Txn2, Msrb1, Atox1, Mtr, and Atp2a2, as well as decreased the mRNA level of Dhfr gene; while NAC could rescue the expression of these genes. Taken together, oxidative stress was involved in BPA-induced apoptosis of mouse Leydig cells.

Identification of a ferroptosis-related gene pair biomarker with immune infiltration landscapes in ischemic stroke: a bioinformatics-based comprehensive study.

BACKGROUND: Ischemic stroke (IS) is a principal contributor to long-term disability in adults. A new cell death mediated by iron is ferroptosis, characterized by lethal aggregation of lipid peroxidation. However, a paucity of ferroptosis-related biomarkers early identify IS until now. This study investigated potential ferroptosis-related gene pair biomarkers in IS and explored their roles in immune infiltration. RESULTS: In total, we identified 6 differentially expressed ferroptosis-related genes (DEFRGs) in the metadata cohort. Of these genes, 4 DEFRGs were incorporated into the competitive endogenous RNA (ceRNA) network, including 78 lncRNA-miRNA and 16 miRNA-mRNA interactions. Based on relative expression values of DEFRGs, we constructed gene pairs. An integrated scheme consisting of machine learning algorithms, ceRNA network, and gene pair was proposed to screen the key DEFRG biomarkers. The receiver operating characteristic (ROC) curve witnessed that the diagnostic performance of DEFRG pair CDKN1A/JUN was superior to that of single gene. Moreover, the CIBERSORT algorithm exhibited immune infiltration landscapes: plasma cells, resting NK cells, and resting mast cells infiltrated less in IS samples than controls. Spearman correlation analysis confirmed a significant correlation between plasma cells and CDKN1A/JUN (CDKN1A: r = - 0.503, P < 0.001, JUN: r = - 0.330, P = 0.025). CONCLUSIONS: Our findings suggested that CDKN1A/JUN could be a robust and promising gene-pair diagnostic biomarker for IS, regulating ferroptosis during IS progression via C9orf106/C9orf139-miR-22-3p-CDKN1A and GAS5-miR-139-5p/miR-429-JUN axes. Meanwhile, plasma cells might exert a vital interplay in IS immune microenvironment, providing an innovative insight for IS therapeutic target.

Pentoxifylline alleviates ischemic white matter injury through up-regulating Mertk-mediated myelin clearance.

BACKGROUND: Vascular dementia (VAD) is the second most common type of dementia lacking effective treatments. Pentoxifylline (PTX), a nonselective phosphodiesterase inhibitor, displays protective effects in multiple cerebral diseases. In this study, we aimed to investigate the therapeutic effects and potential mechanisms of PTX in VAD. METHODS: Bilateral common carotid artery stenosis (BCAS) mouse model was established to mimic VAD. Mouse behavior was tested by open field test, novel object recognition test, Y-maze and Morris water maze (MWM) tests. Histological staining, magnetic resonance imaging (MRI) and electron microscopy were used to define white matter integrity. The impact of PTX on microglia phagocytosis, peroxisome proliferator-activated receptors-γ (PPAR-γ) activation and Mer receptor tyrosine kinase (Mertk) expression was assessed by immunofluorescence, western blotting and flow cytometry with the application of microglia-specific Mertk knockout mice, Mertk inhibitor and PPAR-γ inhibitor. RESULTS: Here, we found that PTX treatment alleviated cognitive impairment in novel object recognition test, Y-maze and Morris water maze tests. Furthermore, PTX alleviated white matter injury in corpus callosum (CC) and internal capsule (IC) areas as shown by histological staining and MRI analysis. PTX-treatment group presented thicker myelin sheath than vehicle group by electron microscopy. Mechanistically, PTX facilitated microglial phagocytosis of myelin debris by up-regulating the expression of Mertk in BCAS model and primary cultured microglia. Importantly, microglia-specific Mertk knockout blocked the therapeutic effects of PTX in BCAS model. Moreover, Mertk expression was regulated by the nuclear translocation of PPAR-γ. Through modulating PPAR-γ, PTX enhanced Mertk expression. CONCLUSIONS: Collectively, our results demonstrated that PTX showed therapeutic potentials in VAD and alleviated ischemic white matter injury via modulating Mertk-mediated myelin clearance in microglia.

Speckle denoising based on deep learning via a conditional generative adversarial network in digital holographic interferometry.

Speckle denoising can improve digital holographic interferometry phase measurements but may affect experimental accuracy. A deep-learning-based speckle denoising algorithm is developed using a conditional generative adversarial network. Two subnetworks, namely discriminator and generator networks, which refer to the U-Net and DenseNet layer structures are used to supervise network learning quality and denoising. Datasets obtained from speckle simulations are shown to provide improved noise feature extraction. The loss function is designed by considering the peak signal-to-noise ratio parameters to improve efficiency and accuracy. The proposed method thus shows better performance than other denoising algorithms for processing experimental strain data from digital holography.

Renal Interstitial Inflammation Predicts Nephropathy Progression in IgA Nephropathy: A Two-Center Cohort Study.

INTRODUCTION: Renal interstitial inflammation often presents in immunoglobulin A nephropathy (IgAN), but its predictive role in kidney disease progression remains controversial. METHODS: This retrospective two-center cohort study included 1,420 adult IgAN patients between January 2003 and May 2018 followed for a median of approximately 7 years at two Chinese hospitals. The predictor was renal interstitial inflammation within the total cortical interstitium (none/mild [0-25%], moderate [26-50%], or severe [>50%]). For the further propensity score matching analyses, the participants with moderate and severe level of interstitial inflammation were pooled to match those with none/mild level of interstitial inflammation. The outcomes included the rate of kidney function decline, and the composite kidney endpoint event defined as a >40% reduction in the estimated glomerular filtration rate, end-stage kidney disease. Linear regression and Cox proportional hazards regression analyses were used to examine the association between interstitial inflammation and the outcomes. The predictive performance of the model also assessed using multivariate logistic regression analyses with the receiver operating characteristic curve analysis. Reclassification was assessed using the continuous net reclassification improvement and integrated discrimination improvement adapted for censoring for the assessment of the model with or without interstitial inflammation. RESULTS: For the check of reproducibility, the kappa statistic was 0.71, and intraclass correlation coefficient was 0.77. After adjustment for relating covariates, a higher level of interstitial inflammation was associated with a faster rate of kidney function decline (eGFR slope [mL/min/1.73 m2] of 1.34 [95% CI: -2.56 to 5.23], 3.50 [95% CI: -0.40 to 7.40], and 7.52 [95% CI: 3.02 to 12.01]) in the patients with none/mild, moderate, and severe interstitial inflammation, respectively, in the multivariable linear regression models and with an increased risk of kidney disease progression (HR for moderate vs. none/mild, 1.85; 95% CI: 1.10-3.13; HR for severe vs. none/mild, 2.95; 95% CI: 1.52-5.73) in the multivariable Cox proportional hazards models. Analyses in the propensity score-matched cohort, subgroups, and the sensitive analyses yielded consistent results. The receiver operating curves indicated a higher area under the curve of 0.83 in the model with interstitial inflammation compared with 0.81 in that without interstitial inflammation. In addition, incorporating interstitial inflammation into the International IgAN Risk Prediction Tool improved the diagnostic power of the algorithm to predict risk of progression. CONCLUSION: Interstitial inflammation is a reproducible pathologic parameter that may be adopted as a predictor for kidney disease progression in patients with IgAN.

An ultra-sensitive near-infrared fluorescent probe based on triphenylamine with high selectivity detecting the keratin.

In this work, a novel triphenylamine derivative probe TPA-1 was designed and synthesized with a mechanism of aggregation induced emission (AIE) and twisted intramolecular charge transfer (TICT) in a microenvironment. It can be used for the detection of keratin with AIE enhanced characterization in near infrared (NIR) emission. The sensitivity and selectivity for keratin detection were also studied. In the physiological pH range, the detection of TPA-1 to keratin was not interfered by other proteins and amino acids, and had excellent specificity and photostability. TPA-1 can also be used for viscosity detection.

A novel near-infrared fluorescent probe based on triphenylamine derivatives for the rapid and sensitive detection of heparin.

In this study, a positively charged near-infrared fluorescent probe (TPA-P+) was constructed by connecting a pyridine cation with triphenylamine and successfully used for the detection of heparin. The probe has the following characteristics: (1) TPA-P+ exhibited both AIE and TICT characteristics. (2) TPA-P+ could detect heparin by the introduction of a pyridine cation into TPA-P+, which increased the electrostatic interaction between the probe and heparin. (3) The probe has high sensitivity and good selectivity towards heparin and responds quickly. (4) Heparin detection using TPA-P+ was verified by protamine and was found to be reversible and effective. (5) The fluorescence intensity of TPA-P+ has good linearity with heparin concentration in the range of 0-16.0 µg mL-1 in human serum albumin.

Super enhancer-LncRNA SENCR promoted cisplatin resistance and growth of NSCLC through upregulating FLI1.

BACKGROUND: Super enhancer-lncRNA smooth muscle and endothelial cell-enriched migration/differentiation-associated lncRNA (SENCR) were highly overexpressed in cisplatin-resistant A549/DDP cells, while the mechanism was unclear. METHODS: SE-lncRNA SENCR and FLI1 mRNA expression in A549/DDP cell, LAD tissues were detected. SENCR knockdown of A549/DDP cell and SENCR overexpression of cisplatin-sensitive A549 cell were constructed. Experiments of cell-confirmed function of SENCR and the correlation between SENCR and FLI1 were validated. RESULTS: The expression of SENCR and FLI1 mRNA in A549/DDP cell were both upregulated and mainly localized in the nucleus. Compared with DDP-sensitive tissues with disease relief, SENCR expression was higher in DDP-resistant tissues with disease progression from LAD. Knockdown of SENCR in A549/DDP reduced proliferation ability and cisplatin resistance, consistent with the decreased levels of proteins PCNA, MDMX, and P-gp. Besides, whatever without cisplatin or with 2 µg/ml cisplatin, knockdown of SENCR reduced the migration, invasion, and colony formation abilities of A549/DDP cell and promoted apoptosis. However, when SENCR was overexpressed in A549 cell, all above results were reversed. Mechanistically, FLI1 expression was reduced after knocking down SENCR, while overexpressing SENCR increased FLI1 expression. CONCLUSION: SE-LncRNA SENCR was upregulated in A549/DDP, which could promote cisplatin resistance and growth of NSCLC cell through upregulating FLI1 expression.

Construction and analysis of expression profile of exosomal lncRNAs in pleural effusion in lung adenocarcinoma.

BACKGROUND: Lung adenocarcinoma (LUAD) is a highly malignant tumor with a very low five-year survival rate. In this study, we aimed to identify differentially expressed long-chain non-coding RNA (lncRNAs) and mRNAs from benign and malignant pleural effusion exosomes. METHODS: We used gene microassay and quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR) to detect and verify differentially expressed mRNAs and lncRNAs in benign and malignant pleural effusion exosomes. Gene Ontology (GO) functional significance and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway significance enrichment analyses were performed to identify the difference in biological processes and functions between different mRNAs. We selected the lncRNA ZBED5-AS1 with an upregulated differential fold of 3.003 and conducted a preliminary study on its cellular function. RESULTS: Gene microassay results revealed that 177 differentially expressed lncRNAs were upregulated, and 215 were downregulated. The top 10 upregulated were FMN1, AL118505.1, LINC00452, AL109811.2, CATG00000040683.1, AC137932.1, AC008619.1, AL450344.1, AC092718.6, and ZBED5-AS1. The top 10 downregulated were TEX41, G067726, JAZF1-AS1, AC027328.1, AL445645.1, AL022345.4, AC008572.1, AC123777.1, AC093714.1, and PHKG1. For the mRNAs, 79 were upregulated, and 123 were notably downregulated. GO analysis revealed that the upregulated differential mRNAs were mainly involved in "cellular response to acidic pH" (biological processes), "endoplasmic reticulum part" (cellular components), and "at DNA binding, cyclase activity" (molecular functions). KEGG pathways were found to be related to V. cholerae infection, Parkinson's disease, and cell adhesion molecules. RT-qPCR showed that ZBED5-AS1 was highly expressed in LUAD tissues, cells, and benign and malignant pleural fluid exosomes. Overexpression of ZBED5-AS1 could significantly promote the proliferation, migration, invasion, and colony formation of LUAD cells, and knockdown had the opposite consequence. CONCLUSION: The pleural effusion exosomes from patients with LUAD include several improperly expressed genes, and lncRNA-ZBED5-AS1 is a new biomarker that aids in our understanding of the occurrence and progression of LUAD.

Role of autophagy in lysophosphatidylcholine-induced apoptosis in mouse Leydig cells.

Lysophosphatidylcholine (LPC), a major class of glycerophospholipids ubiquitously present in most tissues, plays a dominant role in many diseases, while it is still unknown about the potential mechanism of LPC affecting the testicular Leydig cells. In the present study, mouse TM3 Leydig cells in vitro were treated with LPC for 48 h. LPC was found to significantly induce apoptosis and oxidative stress of mouse TM3 Leydig cells; while inhibition of oxidative stress by N-acetyl-L-cysteine, an inhibitor of oxidative stress, could rescue the induction of apoptosis, indicating that LPC induced apoptosis of mouse TM3 Leydig cells via oxidative stress. Interestingly, LPC was showed to inhibit autophagy; however, induction of autophagy by rapamycin significantly alleviated the induction of apoptosis by LPC. Taken together, oxidative stress was involved in LPC-induced apoptosis of mouse TM3 Leydig cells, and autophagy might play a protective role in LPC-induced apoptosis.

Preservation of the left colic artery in modified laparoscopic anterior rectal resections without auxiliary abdominal incisions for transanal specimen retrieval.

BACKGROUND: Laparoscopic low anterior rectal resection is the most widely used surgical procedure for middle and low rectal cancer. The aim of this study was to investigate the feasibility and safety of the extracorporeal placement of the anvil in preserving the left colic artery in laparoscopic low anterior rectal resection without auxiliary incisions for transanal specimen retrieval in this research. METHODS: Clinical data and follow-up data of patients undergoing laparoscopic low anterior rectal resection from January 2017 to October 2020 were collected. The resections were modified such that the resisting nail holder was extracorporeally placed for the transanal exenteration of the specimen without using auxiliary abdominal incisions while preserving the left colic artery. By analyzing the data of anastomotic stenosis, anastomotic bleeding and anastomotic fistulas after surgery, the advantages and disadvantages of this surgical method for patients were clarified. RESULTS: A total of 22 patients were enrolled. Five of 22 patients simultaneously underwent double-barrel terminal ileostomy. The postoperative exhaust time was 2-7 (median, 3) days. Postoperative anastomotic bleeding occurred in one patient, postoperative anastomotic fistula occurred in four patients, and postoperative anastomotic stenosis occurred in six patients. There were four patients with postoperative distant metastasis, of which three had concomitant local recurrence. Seventeen patients had no obvious symptoms or signs of recurrent metastases during follow-up appointments, and one died of liver failure. CONCLUSIONS: Modified laparoscopic low anterior rectal resection, which resects the specimen through anus eversion by inserting the anvil extracorporeally while preserving the left colic artery, is safe and feasible for patients with low rectal cancer.

Microbe-Derived Antioxidants Reduce Lipopolysaccharide-Induced Inflammatory Responses by Activating the Nrf2 Pathway to Inhibit the ROS/NLRP3/IL-1ß Signaling Pathway.

Inflammation plays an important role in the innate immune response, yet overproduction of inflammation can lead to a variety of chronic diseases associated with the innate immune system; therefore, modulation of the excessive inflammatory response has been considered a major strategy in the treatment of inflammatory diseases. Activation of the ROS/NLRP3/IL-1ß signaling axis has been suggested to be a key initiating phase of inflammation. Our previous study found that microbe-derived antioxidants (MA) are shown to have excellent antioxidant and anti-inflammatory properties; however, the mechanism of action of MA remains unclear. The current study aims to investigate whether MA could protect cells from LPS-induced oxidative stress and inflammatory responses by modulating the Nrf2-ROS-NLRP3-IL-1ß signaling pathway. In this study, we find that MA treatment significantly alleviates LPS-induced oxidative stress and inflammatory responses in RAW264.7 cells. MA significantly reduce the accumulation of ROS in RAW264.7 cells, down-regulate the levels of pro-inflammatory factors (TNF-α and IL-6), inhibit NLRP3, ASC, caspase-1 mRNA, and protein levels, and reduce the mRNA, protein levels, and content of inflammatory factors (IL-1ß and IL-18). The protective effect of MA is significantly reduced after the siRNA knockdown of the NLRP3 gene, presumably related to the ability of MA to inhibit the ROS-NLRP3-IL-1ß signaling pathway. MA is able to reduce the accumulation of ROS and alleviate oxidative stress by increasing the content of antioxidant enzymes, such as SOD, GSH-Px, and CAT. The protective effect of MA may be due to its ability of MA to induce Nrf2 to enter the nucleus and initiate the expression of antioxidant enzymes. The antioxidant properties of MA are further enhanced in the presence of the Nrf2 activator SFN. After the siRNA knockdown of the Nrf2 gene, the antioxidant and anti-inflammatory properties of MA are significantly affected. These findings suggest that MA may inhibit the LPS-stimulated ROS/NLRP3/IL-1ß signaling axis by activating Nrf2-antioxidant signaling in RAW264.7 cells. As a result of this study, MA has been found to alleviate inflammatory responses and holds promise as a therapeutic agent for inflammation-related diseases.

Tauroursodeoxycholic acid prevents Burkholderia pseudomallei-induced endoplasmic reticulum stress and is protective during melioidosis in mice.

BACKGROUND: Burkholderia pseudomallei, a facultative intracellular bacterium, is the aetiological agent of melioidosis that is responsible for up to 40% sepsis-related mortality in epidemic areas. However, no effective vaccine is available currently, and the drug resistance is also a major problem in the treatment of melioidosis. Therefore, finding new clinical treatment strategies in melioidosis is extremely urgent. RESULTS: We demonstrated that tauroursodeoxycholic acid (TUDCA), a clinically available endoplasmic reticulum (ER) stress inhibitor, can promote B. pseudomallei clearance both in vivo and in vitro. In this study, we investigated the effects of TUDCA on the survival of melioidosis mice, and found that treatment with TUDCA significantly decreased intracellular survival of B. pseudomallei. Mechanistically, we found that B. pseudomallei induced apoptosis and activated IRE1 and PERK signaling ways of ER stress in RAW264.7 macrophages. TUDCA treatment could reduce B. pseudomallei-induced ER stress in vitro, and TUDCA is protective in vivo. CONCLUSION: Taken together, our study has demonstrated that B. pseudomallei infection results in ER stress-induced apoptosis, and TUDCA enhances the clearance of B. pseudomallei by inhibiting ER stress-induced apoptosis both in vivo and in vitro, suggesting that TUDCA could be used as a potentially alternative treatment for melioidosis.

MicroRNA-146a inhibits autophagy to maintain the intracellular survival of Burkholderia pseudomallei by targeting LIPA.

Burkholderia pseudomallei is the etiological agent of melioidosis, which is an emerging infectious disease endemic to many tropical regions. Autophagy is an intrinsic cellular process that degrades cytoplasmic components and plays an important role in protecting the host against pathogens. Like many intracellular pathogens, B. pseudomallei can evade the autophagy-dependent cellular clearance. However, the underlying mechanism remains unclear. In this study, we applied a combination of multiple assays to monitor autophagy processes and found that B. pseudomallei induced an incomplete autophagic flux and eliminate autophagy clearance in macrophages by blocking autophagosome-lysosome fusion. Based on a high-throughput microarray screening, we found that LIPA (lysosomal acid LIPAse A) was downregulated during B. pseudomallei infection. MiR-146a was then identified to be specifically upregulated upon infection with B. pseudomallei and further regulated LIPA expression by interacting with 3'UTR of LIPA. Furthermore, overexpression of miR-146a contributed to the defect of autophagic flux caused by B. pseudomallei and was beneficial for the survival of B. pseudomallei in macrophages. Therefore, our findings suggest that miR-146a inhibits autophagy via posttranscriptional suppression of LIPA expression to maintain B. pseudomallei survival in macrophages.

The HDAC3 inhibitor RGFP966 ameliorated ischemic brain damage by downregulating the AIM2 inflammasome.

Histone deacetylases 3 (HDAC3) modulates the acetylation state of histone and non-histone proteins and could be a powerful regulator of the inflammatory process in stroke. Inflammasome activation is a ubiquitous but poorly understood consequence of acute ischemic stroke. Here, we investigated the potential contributions of HDAC3 to inflammasome activation in primary cultured microglia and experimental stroke models. In this study, we documented that HDAC3 expression was increased in microglia of mouse experimental stroke model. Intraperitoneal injection of RGFP966 (a selective inhibitor of HDAC3) decreased infarct size and alleviated neurological deficits after the onset of middle cerebral artery occlusion (MCAO). In vitro data indicated that LPS stimulation evoked a time-dependent increase of HDAC3 and absent in melanoma 2 (AIM2) inflammasome in primary cultured microglia. Interestingly, AIM2 was subjected to spatiotemporal regulation by RGFP966. The ability of RGFP966 to inhibit the AIM2 inflammasome was confirmed in an experimental mouse model of stroke. As expected, AIM2 knockout mice also demonstrated significant resistance to ischemia injury compared with their wild-type littermates. RGFP966 failed to exhibit extra protective effects in AIM2-/- stroke mice. Furthermore, we found that RGFP966 enhanced STAT1 acetylation and subsequently attenuated STAT1 phosphorylation, which may at least partially contributed to the negative regulation of AIM2 by RGFP966. Together, we initially found that RGFP966 alleviated the inflammatory response and protected against ischemic stroke by regulating the AIM2 inflammasome.