Microglia-induced autophagic death of neurons via IL-6/STAT3/miR-30d signaling following hypoxia/ischemia.

BACKGROUND: There is a relationship between autophagy and the occurrence, maintenance, and progression of several neurodegenerative diseases. The activation of microglia after ischemia contributes to neuronal injury via proinflammatory cytokines and neurotoxic elements. The purpose of this study was to evaluate the function of autophagy in the microglia-mediated death of neuronal cells. METHODS AND RESULTS: Microglial activation by oxygen/glucose deprivation induced both apoptosis and autophagy in neuron-like PC12 cells. Microglia-derived interleukin (IL)-6 induced PC12 cell apoptosis in vitro; however, this effect was inhibited by the autophagy inhibitor chloroquine. Further analysis demonstrated that miR-30d in PC12 cells suppressed microglia-induced PC12 apoptosis and autophagy by directly targeting autophagy protein 5. Moreover, microglia-derived IL-6 activated signal transducer and activator of transcription 3 (STAT3), which can then directly repress miR-30d genes via a conserved STAT3-binding site in its promoter, thereby promoting PC12 cell autophagy and apoptosis. CONCLUSIONS: Our study identified IL-6-dependent autophagy-related signaling between microglia and neurons, which contributed to neuronal apoptosis. Importantly, we also provided potential therapeutic targets for ischemic treatment via the interruption of proinflammatory signaling.

Characteristics, dynamic changes, and prognostic significance of TCR repertoire profiling in patients with renal cell carcinoma.

The co-evolving tumour cells and the systemic immune environment are mutually dysregulated. Tumours affect the immune response in a complex manner. For example, although lymphocytes are mobilized in response to tumours, their function is impaired by tumour progression. This study aimed to explore how the baseline and dynamic renal cell carcinoma (RCC) tumour burdens affect the T-cell repertoire, and whether the baseline T-cell receptor ß-chain (TCRB) diversity predicts prognosis. To characterise the TCRB repertoire, the baseline and follow-up peripheral TCRB repertoires of 45 patients with RCC and 2 patients with benign renal disease patients were examined using high-throughput TCRB sequencing. To explain the significance of TCRB diversity, 56 peripheral leukocyte samples from 28 patients before and after surgery were subjected to transcriptome sequencing. To validate the results, an advanced RCC patient's sample was subjected to single-cell RNA sequencing (scRNA, 10x Genomics). Higher TCRB diversity was found to be correlated with a higher lymphocyte-to-neutrophil ratio, especially indicating more naïve T cells. High-baseline TCRB diversity predicted a better prognosis for stage IV patients, and different tumour burdens exerted distinct effects on the immune status. The pre-operative TCRB diversity was significantly higher in benign and stage I (low tumour burden) RCC patients than in stage IV (high tumour burden) patients. After the tumour burden of advanced patients was mostly relieved, we observed that the TCRB diversity was restored, T-cell exhaustion was reduced, and naïve T-cells were mobilized. It was demonstrated that the circulating TCRB repertoire could reflect the immune status and predict prognosis, and to some extent that cytoreductive nephrectomy (CN) reduces the burden of the immune system in advanced patients, which might provide a good opportunity for immunotherapy. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Feasibility of single position laparoscopic radical nephrectomy and tumor thrombectomy for left renal cell carcinoma with high-risk Mayo grade 0 and 1 tumor thrombus.

BACKGROUND: To explore the feasibility of single-position laparoscopic radical nephrectomy (LRN) and tumor thrombectomy for left renal cell carcinoma with high-risk Mayo 0 and 1 tumor thrombus (TT). METHODS: All patients with left renal cell carcinoma and venous TT (high-risk Mayo grade 0 and 1) who were performed single-position LRN and tumor thrombectomy were involved. After the renal artery was controlled by Hem-o-lok, the left renal vein was dissected through descending colon mesentery. The left renal vein was divided by EndoGIA for high-risk Mayo grade 0 TT. For Mayo grade 1 TT, part of the inferior vena cava was blocked by a bulldog clamp after milking the TT into the left renal vein and the inferior vena cava was sutured after complete excision of the TT. RESULTS: 3 patients were involved and operations were performed successfully without conversion to open surgery. The mean operation time was 136 min and the mean estimated blood loss was 60 mL. No postoperative complications occurred. CONCLUSIONS: It is feasible to control left renal vein and partial inferior vena cava through descending colon mesentery in a single position during LRN and tumor thrombectomy for the treatment of high-risk Mayo grade 0 and 1 TT.

MicroRNA-181c negatively regulates the inflammatory response in oxygen-glucose-deprived microglia by targeting Toll-like receptor 4.

Cerebral hypoxia/ischemia rapidly induces inflammation in the brain, which is characterized by microglial activation and the release of inflammatory cytokines. We have previously demonstrated that miR-181c can directly regulate tumor necrosis factor (TNF)-α production post-transcriptionally. Here, we determined that hypoxia up-regulated TLR4 expression but down-regulated miR-181c expression in primary microglia. We also demonstrated that miR-181c suppresses TLR4 by directly binding its 3'-untranslated region. In addition, miR-181c inhibited NF-κB activation and the downstream production of proinflammatory mediators, such as TNF-α, IL-1ß, and iNOS. Knocking down TLR4 in microglia significantly decreased TLR4 expression and inhibited NF-κB activation and the downstream production of proinflammatory mediators, whereas ectopic TLR4 expression significantly abrogated the suppressed inflammatory response induced by miR-181c. Therefore, our study identified an important role for the miR-181c-TLR4 pathway in hypoxic microglial activation and neuroinflammation. This pathway could represent a potential therapeutic target for cerebral hypoxic diseases associated with microglial activation and the inflammatory response. Cerebral hypoxia/ischemia induces microglial activation and the release of inflammatory cytokines. We found that hypoxia down-regulated miR-181c in primary microglia. In addition, miR-181c inhibited TLR4 expression through binding to its 3'UTR, thus inhibiting NF-kB activation and the production of downstream proinflammatory mediators. Therefore, the miR-181c-TLR4 pathway may be a potential therapeutic target for the treatment of cerebral hypoxic diseases.

miR-21 represses FasL in microglia and protects against microglia-mediated neuronal cell death following hypoxia/ischemia.

A growing body of evidence suggests that microRNA (miRNA) dysregulation contributes to many types of human disease, including central nervous system disorders. In this study, we identified an inverse correlation between the expression of miR-21 and Fas ligand (FasL) during hypoxia-induced microglial activation. Specifically, hypoxia caused the upregulation of FasL expression but the downregulation of miR-21 expression in microglia. Furthermore, we demonstrated that miR-21 suppresses FasL production by directly binding to its 3'-untranslated region. The overproduction of FasL following hypoxic microglial activation induced neuronal apoptosis, whereas the ectopic expression of miR-21 partially protected neurons from cell death caused by hypoxia-activated microglia. Finally, we confirmed that the function of miR-21 in microglia-mediated neuronal injury is dependent on FasL. Our study demonstrates an important role for miRNAs in microglia-mediated neuronal apoptosis, and suggests potential novel therapeutic interventions for cerebral hypoxic diseases associated with microglial activation.

The microRNA miR-181c controls microglia-mediated neuronal apoptosis by suppressing tumor necrosis factor.

BACKGROUND: Post-ischemic microglial activation may contribute to neuronal damage through the release of large amounts of pro-inflammatory cytokines and neurotoxic factors. The involvement of microRNAs (miRNAs) in the pathogenesis of disorders related to the brain and central nervous system has been previously studied, but it remains unknown whether the production of pro-inflammatory cytokines is regulated by miRNAs. METHODS: BV-2 and primary rat microglial cells were activated by exposure to oxygen-glucose deprivation (OGD). Global cerebral ischemia was induced using the four-vessel occlusion (4-VO) model in rats. Induction of pro-inflammatory and neurotoxic factors, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and nitric oxide (NO), were assessed by ELISA, immunofluorescence, and the Griess assay, respectively. The miRNA expression profiles of OGD-activated BV-2 cells were subsequently compared with the profiles of resting cells in a miRNA microarray. BV-2 and primary rat microglial cells were transfected with miR-181c to evaluate its effects on TNF-α production after OGD. In addition, a luciferase reporter assay was conducted to confirm whether TNF-α is a direct target of miR-181c. RESULTS: OGD induced BV-2 microglial activation in vitro, as indicated by the overproduction of TNF-α, IL-1ß, and NO. Global cerebral ischemia/reperfusion injury induced microglial activation and the release of pro-inflammatory cytokines in the hippocampus. OGD also downregulated miR-181c expression and upregulated TNF-α expression. Overproduction of TNF-α after OGD-induced microglial activation provoked neuronal apoptosis, whereas the ectopic expression of miR-181c partially protected neurons from cell death caused by OGD-activated microglia. RNAinterference-mediated knockdown of TNF-α phenocopied the effect of miR-181c-mediated neuronal protection, whereas overexpression of TNF-α blocked the miR-181c-dependent suppression of apoptosis. Further studies showed that miR-181c could directly target the 3'-untranslated region of TNF-α mRNA, suppressing its mRNA and protein expression. CONCLUSIONS: Our data suggest a potential role for miR-181c in the regulation of TNF-α expression after ischemia/hypoxia and microglia-mediated neuronal injury.

Multi-Component Nanofiber Composite Membrane Enabled High PM0.3 Removal Efficiency and Oil/Water Separation Performance in Complex Environment.

Currently, industrial waste gas and oily wastewater are usually at high temperature and contain corrosive components (e.g., acid, alkali, oxidant, or high salt, etc.), presenting great challenges on filtration/separation materials. Here, a multi-purpose Poly(m-phenylene isophthalamide)/polyacrylonitrile/silica (PMIA/PAN/SiO2) nanofiber composite membrane with a high yield was prepared simply via electrospinning to satisfy the demands of air filtration and oil/water separation in complex environments. Under the synergy of PMIA, PAN and SiO2, the composite membrane possesses high PM0.3 removal capacity of 99.69%, robust purification ability against real smoke PM2.5, effective oil/water separation performance of > 99.6%, superior high temperature stability (about 250 °C) and excellent chemical resistance, showing the potential application in filtration/separation process under complex conditions. Moreover, the influence mechanism of SiO2 NPs on mechanical properties and filtration performance was systematically investigated through experiments and simulations, paving the way for future intensive research. This study provides an option for the facile and effective preparation of high-performance filtration/separation membranes applied in the field of dust filtration and oily wastewater separation, even in harsh environments.

A rat model of mild cognitive impairment associated with vascular factor.

Vascular factors have been shown to be important in cognitive impairment and dementia in the elderly. Recent evidence suggests that treatment at the stage of mild cognitive impairment (MCI) can prevent progression to dementia. In this study we established a rat model that simulates the pathophysiological condition of vascular MCI, characterized by gait disturbance in the absence of motor deficits and mild working memory dysfunction and not being demented. Initiation of vascular MCI pathology was not associated with loss of neurons, but was correlated with microglial activation and white matter changes. This MCI rat model will be useful for analysis of effects of vascular factors on cognitive dysfunction and neurodegenerative processes and development of drugs for treatment of this disorder.

MOF-Embedded Bifunctional Composite Nanofiber Membranes with a Tunable Hierarchical Structure for High-Efficiency PM0.3 Purification and Oil/Water Separation.

Herein, a unique hierarchically structured composite nanofiber membrane, consisting of a zeolitic imidazolate framework-8-embedded polyethersulfone (PES@ZIF8) fiber layer and a polysulfonamide/polyethersulfone (PSA/PES) fiber layer, was successfully developed to cope with the complex environments during the actual filtration/separation process and overcome the conflict between high filtration efficiency and low air pressure resistance. Due to the advantages of the synergistic effect of multicomponents and the bi-layer hierarchical structure, the integrated PES@ZIF8-PSA/PES filter possesses an extremely high air filtration efficiency (up to 99.986%) under a very low pressure drop (only 15 Pa), superior PM0.3 purification capacity (close to 99.95%), long-term recycling ability for purifying real smoke PM2.5 from >800 to <10 µg/m3, extremely high temperature resistance (exceed 200 °C), flame retardancy, good chemical stability, satisfactory transmittance, and robust self-cleaning ability. Apart from these, it achieves effective separation of oil-water mixtures and oil-water emulsions as a result of selective wettability including hydrophobicity and superoleophilicity. In particular, the PES@ZIF8-PSA/PES nanofiber membranes maintain outstanding air filtration and oil/water separation properties under the high temperature or strong acid/alkali conditions. This special comprehensive performance gives the PES@ZIF8-PSA/PES-based filtration/separation membranes a wider application prospect ranging from environmental governance to individual protection and industrial security.

Targeting the deubiquitinase STAMBPL1 triggers apoptosis in prostate cancer cells by promoting XIAP degradation.

The zinc metalloprotease STAM-binding protein-like 1 (STAMBPL1) has been identified as a deubiquitinase by specifically cleaving Lys-63-linked polyubiquitin chains, but its cellular function remains unclear. Here we described the potential role of STAMBPL1 in suppression of the intrinsic apoptosis. We observed substantially high amounts of STAMBPL1 proteins in androgen-independent prostate cancer PC3 and DU145 cell lines. STAMBPL1 RNAi depletion triggered caspase-3/-7-dependent apoptosis in PC3 and DU145 cells. STAMBPL1 knockdown-induced apoptosis was accompanied by accumulation of cellular ROS and a decrease in endogenous caspase inhibitor XIAP protein content. Treatment cells with antioxidant NAC delayed STAMBPL1 silencing-induced apoptosis, whereas ectopic expression of XIAP almost completely abrogated apoptosis. We further elucidated that STAMBPL1 knockdown diverted XIAP protein to lysosomal degradation pathway. Taken together, these studies show that STAMBPL1 depletion induces apoptosis by promoting XIAP lysosomal degradation, and suggest that targeting deubiquitinase STAMBPL1 might offer promising therapeutic strategy for prostate cancer.

Cooperation Between the Inflammation and Coagulation Systems Promotes the Survival of Circulating Tumor Cells in Renal Cell Carcinoma Patients.

Most renal cell carcinoma (RCC) patients die from metastasis or recurrence after the spread of cancer to another organ, but the mechanisms underlying the intravascular survival of circulating tumor cells (CTCs) have not been completely deciphered. Additionally, although elevated plasma C-reactive protein (CRP) levels and thrombocytosis are strongly correlated and both indicate a poor prognosis for RCC patients, the bridge connecting inflammation and coagulation remains poorly understood. To explore the complicated relationship among inflammation, the coagulation system and CTC survival, we obtained viable CTC counts and clinical information from 106 treatment-naïve patients. In addition, we performed RNA sequencing on peripheral blood leukocytes from 21 of these patients. Patients with elevated CRP and fibrinogen (FIB) levels had higher CTC counts than patients with normal levels of these indexes. Each pair of the three variables (CTC count, CRP level and FIB level) was positively correlated. According to transcriptomic analysis of blood leukocytes, the functions of the 257 genes identified as being positively correlated with the CTC count indicated neutrophil extracellular trap (NET) formation. Indeed, gene set enrichment analysis (GSEA) suggested that NET formation or increased levels of NET markers would promote CTC viability. Additionally, the calculated NET score was positively correlated with the plasma FIB concentration, and both of these values were increased in patients with elevated CRP levels. Moreover, immunofluorescence staining showed that NETs were entangled with viable renal cancer cells and that the NET frameworks were decorated with NET-derived tissue factor (TF). Finally, analysis of 533 RCC samples from The Cancer Genome Atlas (TCGA) indicated that the NET score and TF value are independent prognostic factors for RCC patients. Collectively, NETs formed by intravascular neutrophils further activate the coagulation system. Both the DNA scaffold sprouted and fibrin net triggered by NETs anchor and shield CTCs from attack. Thus, degrading this framework maybe could destroy the double shelter of CTCs, the pioneers of metastasis.

Feasibility of prostatectomy without prostate biopsy in the era of new imaging technology and minimally invasive techniques.

BACKGROUND: Routinely, after receiving prostate specific antigen (PSA) testing and digital rectum examination, patients with suspected prostate cancer are required to undergo prostate biopsy. However, the ability of ultrasound-guided prostate biopsy to detect prostate cancer is limited. Nowadays, a variety of diagnostic methods and more sensitive diagnostic methods, such as multi-parameter prostate magnetic resonance imaging (mpMRI) and prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA PET/CT) can be applied clinically. Furthermore, laparoscopic/robot-assisted prostatectomy is also a safe and effective procedure for the treatment of benign prostatic hyperplasia. So maybe it is time to reconsider the necessary to perform prostate biopsy before radical prostatectomy. AIM: To explore the feasibility of radical prostatectomy without prostate biopsy in the era of new imaging technology and minimally invasive techniques. METHODS: From June 2014 to November 2018, 11 cases of laparoscopic radical prostatectomy without prostate biopsy were performed at the three tertiary medical centers involved in this study. All patients received prostate magnetic resonance imaging and prostate cancer was suspected, including six patients with positive 68Ga-PSMA PET/CT results. Laparoscopic radical prostatectomy and pelvic lymph node dissection were performed for all patients. RESULTS: All surgeries were accomplished successfully. The mean age was 69 ± 7.7 year, the mean body mass index was 24.7 ± 1.6 kg/m2, the range of serum PSA was 4.3 to >1000 ng/mL, and the mean prostate volume was 40.9 ± 18.3 mL. The mean operative time was 96 ± 23.3 min, the mean estimated blood loss was 90 ± 90.9 mL, and the median duration of catheter placement was 14 d. The final pathology confirmed that all specimens were prostate cancer except one case of benign prostatic hyperplasia. No major complications occurred in 90 d postoperatively. CONCLUSION: The current practice of mandating a prostatic biopsy before prostatectomy should be reconsidered in the era of new imaging technology and minimally invasive techniques. Radical prostatectomy could be carried out without the evidence of malignancy. Large-sample randomized controlled trials are definitely required to confirm the feasibility of this new concept.

Injectable co-gels of collagen and decellularized vascular matrix improve MSC-based therapy for acute kidney injury.

Transplantation of mesenchymal stem cells (MSCs) is promising for treatment of acute kidney injury (AKI), but their therapeutic effects are often limited under normal conditions. In this study, we prepared the co-gels of decellularized vascular matrix and collagen, and investigated whether the co-gels increase the therapeutic potentials of MSCs on AKI. In vitro studies indicated that the co-gels enhanced the paracrine effects of MSCs, and significantly reduced the apoptosis of MSCs under oxidative environments. When the co-gels were co-transplanted with MSCs into the kidney of model rats with ischemia-reperfusion (I/R)-induced AKI, the survival and paracrine effects of MSCs were enhanced in the injured kidney. More importantly, the co-gels increased the therapeutic effects of MSCs for AKI, as indicated by cell apoptosis, tissue damage, vascularization and renal function. Therefore, the co-gels of decellularized vascular matrix and collagen improved the therapeutic effects of MSCs, and might be promising for AKI treatment.