Background It is known that excessive release of glutamate can induce excitotoxicity in neurons and lead to seizure. Dexamethasone has anti-seizure function. The aim of this study was to investigate ...glutamatedexamethasone interaction in the pathogenesis of epilepsy, identify differentially expressed genes in the hippocampus of glutamate-induced epileptic rats by mRNA differential display, and observe the effects of dexamethasone on these genes expression.
Methods Seizure models were established by injecting 5μl （250 μg/μl） monosodium glutamate （MSG） into the lateral cerebral ventricle in rats. Dexamethasone （5 mg/kg） was injected intraperitoneally at 30 minutes after MSG inducing convulsion. The rats＇ behavior and electroencephalogram （EEG） were then recorded for 1 hour. The effects of dexamethasone on gene expression were observed in MSG-induced epileptic rats at 1 hour and 6 hours after the onset of seizure by mRNA differential display. The differentially expressed genes were confirmed by Dot blot.
Results EEG and behaviors showed that MSG did induce seizure, and dexamethasone could clearly alleviate the symptom, mRNA differential display showed that MSG increased the expression of some genes in epileptic rats and dexamethasone could downregulate their expression. From more than 10 differentially expressed eDNA fragments, we identified a 226 bp eDNA fragment that was expressed higher in the hippocampus of epileptic rats than that in the control group. Its expression was reduced after the administration of dexamethasone. Sequence analysis and protein alignment showed that the predicted amino acid sequence of this cDNA fragment kept 43% identity to agmatinase, a member of the ureohydrolase superfamily.
Conclusions The results of the current study suggest that the product of the 226 bp eDNA has a function similar to agmatinase. Dexamethasone might relax alleviate seizure by inhibiting expression of the gene.
Objective
Caveolin‐1 (Cav‐1) is expressed abundantly in adipose tissue and involved in many physiological processes. While Cav‐1 has been reported to be secreted in pancreatic acinar cells and LNCaP ...prostate cancer cells, its secretion from adipose tissue awaits investigation.
Methods
Cav‐1 secretion from 3T3‐L1 adipocytes and fat tissues from normal chow diet‐ and high‐fat diet (HFD)‐fed mice was measured. Functions and uptake of secreted Cav‐1 proteins were assessed by adding Cav‐1 back to preadipocytes and LNCaP cells.
Results
Cav‐1 secretion was evident in adipose tissues and were substantially promoted in HFD‐fed mice. Cav‐1 was detectable in the conditioned media of 3T3‐L1 adipocytes but not preadipocytes. Hypertrophied adipocytes induced by glucose and fatty acids secreted more Cav‐1, suggesting that hypertrophied adipocytes were responsible for enhanced Cav‐1 secretion in obese mice. Secreted Cav‐1 was taken up by preadipocytes and LNCaP cells. 3T3‐L1 preadipocytes overexpressing Cav‐1 were better differentiated, suggesting that secreted Cav‐1 may promote adipogenesis. Hypertrophied 3T3‐L1 adipocytes enhanced ERK1/2 activation, and the attenuation of ERK1/2 activity by PD98059 inhibited Cav‐1 secretion.
Conclusions
Cav‐1 is actively secreted from adipocytes as a putative adipogenesis enhancer. Hypertrophied adipocytes secrete Cav‐1 via ERK1/2‐dependent mechanisms to promote adipogenesis, thus establishing a vicious cycle.
To discover novel markers for improving the efficacy of pancreatic cancer (PC) diagnosis, the secretome of two PC cell lines (BxPC-3 and MIA PaCa-2) was profiled. UL16 binding protein 2 (ULBP2), one ...of the proteins identified in the PC cell secretome, was selected for evaluation as a biomarker for PC detection because its mRNA level was also found to be significantly elevated in PC tissues.
ULBP2 expression in PC tissues from 67 patients was studied by immunohistochemistry. ULBP2 serum levels in 154 PC patients and 142 healthy controls were measured by bead-based immunoassay, and the efficacy of serum ULBP2 for PC detection was compared with the widely used serological PC marker carbohydrate antigen 19-9 (CA 19-9).
Immunohistochemical analyses revealed an elevated expression of ULPB2 in PC tissues compared with adjacent non-cancerous tissues. Meanwhile, the serum levels of ULBP2 among all PC patients (n = 154) and in early-stage cancer patients were significantly higher than those in healthy controls (p<0.0001). The combination of ULBP2 and CA 19-9 outperformed each marker alone in distinguishing PC patients from healthy individuals. Importantly, an analysis of the area under receiver operating characteristic curves showed that ULBP2 was superior to CA 19-9 in discriminating patients with early-stage PC from healthy controls.
Collectively, our results indicate that ULBP2 may represent a novel and useful serum biomarker for pancreatic cancer primary screening.
Summary： Endothelin-3 （ET-3） is aberrantly expressed in both metastatic melanoma tissues and cul tured melanoma cells. Our previous work showed that ET-3 could promote survival of metastatic mela ...noma cells via its altered expression. In this study, we investigated the mechanisms responsible for these gene-induced phenotypes in melanoma cells. An ET-3 gene sequence-specific shRNA vector pLVTHM-ET3-RNAi was constructed and transfected into human malignant melanoma cells A375 and MMRU, and the resultant molecular events and cellular changes were examined. As compared with the empty-vector group, cell proliferation was slowed down, and the growth inhibition rates were 38.9% in A375 cells and 38.4% in MMRU cells after transfection. In addition, cell invasion capability was also inhibited, with a reduction of 62.2% in A375 cells and 54.3% in MMRU cells. The percentage of apoptotic cells was found to increase. Meanwhile, in both cell lines, secreted protein acidic and rich in cy teine （SPARC） levels were down-regulated together with inhibition of its upstream signaling molecule, NF-kB. Thus, the current results suggested that down-regulated expression of ET3 attenuates the ma lignant behaviors of human melanoma ceils partially by decreasing the expression of SPARC and NF-kB.
Feline infectious peritonitis (FIP), caused by a mutated feline coronavirus, is one of the most serious and fatal viral diseases in cats. The disease remains incurable, and there is no effective ...vaccine available. In light of the pathogenic mechanism of feline coronavirus that relies on endosomal acidification for cytoplasmic entry, a novel vacuolar ATPase blocker, diphyllin, and its nanoformulation are herein investigated for their antiviral activity against the type II feline infectious peritonitis virus (FIPV). Experimental results show that diphyllin dose-dependently inhibits endosomal acidification in fcwf-4 cells, alters the cellular susceptibility to FIPV, and inhibits the downstream virus replication. In addition, diphyllin delivered by polymeric nanoparticles consisting of poly(ethylene glycol)-block-poly(lactide-co-glycolide) (PEG-PLGA) further demonstrates an improved safety profile and enhanced inhibitory activity against FIPV. In an in vitro model of antibody-dependent enhancement of FIPV infection, diphyllin nanoparticles showed a prominent antiviral effect against the feline coronavirus. In addition, the diphyllin nanoparticles were well tolerated in mice following high-dose intravenous administration. This study highlights the therapeutic potential of diphyllin and its nanoformulation for the treatment of FIP.
Classifying the sub-categories of an object from the same super-category (e.g., bird species and cars) in fine-grained visual classification (FGVC) highly relies on discriminative feature ...representation and accurate region localization. Existing approaches mainly focus on distilling information from high-level features. In this paper, by contrast, we show that by integrating low-level information (e.g., color, edge junctions, texture patterns), performance can be improved with enhanced feature representation and accurately located discriminative regions. Our solution, named Attention Pyramid Convolutional Neural Network (AP-CNN), consists of 1) a dual pathway hierarchy structure with a top-down feature pathway and a bottom-up attention pathway, hence learning both high-level semantic and low-level detailed feature representation, and 2) an ROI-guided refinement strategy with ROI-guided dropblock and ROI-guided zoom-in operation, which refines features with discriminative local regions enhanced and background noises eliminated. The proposed AP-CNN can be trained end-to-end, without the need of any additional bounding box/part annotation. Extensive experiments on three popularly tested FGVC datasets (CUB-200-2011, Stanford Cars, and FGVC-Aircraft) demonstrate that our approach achieves state-of-the-art performance. Models and code are available at https://github.com/PRIS-CV/AP-CNN_Pytorch-master.
Natural killer (NKs) cells are cytotoxic effector cells, which can modulate tumor metastasis according to their function; however, the role of NK cells in lung cancer has not been extensively ...investigated. In this study, we determined the functional profiles of NK cells in a hypoxic tumor microenvironment (TME) of lung cancer. We revealed CD226 downregulation and functional repression of NK cells after hypoxic lung cancer priming and we then investigated their interaction with extracellular vesicles (EVs) and miR-150-5p. We also found that NK cells from lung cancer patients had lower expression of CD226 on their surface and exhibited a pro-inflammatory, pro-angiogenic and tumorigenesis phenotype by expressing VEGF, CXCL1, CXCL8, S100A8 and MMPs. Moreover, inhibition of miR-150 improved tumor surveillance by reversing CD226 expression and subsequently reinstating cytotoxic NK cell activity in an animal model. Our study introduces a new scenario for the pro-inflammatory and pro-angiogenic activities of NK cells in the hypoxic TME in lung cancer.
Idiopathic pulmonary fibrosis (IPF) is featured with inflammation and extensive lung remodeling caused by overloaded deposition of extracellular matrix. Scutellarin is the major effective ingredient ...of breviscapine and its anti-inflammation efficacy has been reported before. Nevertheless, the impact of scutellarin on IPF and the downstream molecular mechanism remain unclear. In this study, scutellarin suppressed BLM-induced inflammation via NF-κB/NLRP3 pathway both in vivo and in vitro. BLM significantly elevated p-p65/p65 ratio, IκBα degradation, and levels of NLRP3, caspase-1, caspase-11, ASC, GSDMD
, IL-1β, and IL-18, while scutellarin reversed the above alterations except for that of caspase-11. Scutellarin inhibited BLM-induced epithelial-mesenchymal transition (EMT) process in vivo and in vitro. The expression levels of EMT-related markers, including fibronectin, vimentin, N-cadherin, matrix metalloproteinase 2 (MMP-2) and MMP-9, were increased in BLM group, and suppressed by scutellarin. The expression level of E-cadherin showed the opposite changes. However, overexpression of NLRP3 eliminated the anti-inflammation and anti-EMT functions of scutellarin in vitro. In conclusion, scutellarin suppressed inflammation and EMT in BLM-induced pulmonary fibrosis through NF-κB/NLRP3 signaling.
Until recently, the intrinsically high level of cross-talk between immune cells, the complexity of immune cell development, and the pleiotropic nature of cytokine signaling have hampered progress in ...understanding the mechanisms of immunosuppression by which tumor cells circumvent native and adaptive immune responses. One technology that has helped to shed light on this complex signaling network is the cytokine antibody array, which facilitates simultaneous screening of dozens to hundreds of secreted signal proteins in complex biological samples. The combined applications of traditional methods of molecular and cell biology with the high-content, high-throughput screening capabilities of cytokine antibody arrays and other multiplexed immunoassays have revealed a complex mechanism that involves multiple cytokine signals contributed not just by tumor cells but by stromal cells and a wide spectrum of immune cell types. This review will summarize the interactions among cancerous and immune cell types, as well as the key cytokine signals that are required for tumors to survive immunoediting in a dormant state or to grow and spread by escaping it. Additionally, it will present examples of how probing secreted cell–cell signal networks in the tumor microenvironment (TME) with cytokine screens have contributed to our current understanding of these processes and discuss the implications of this understanding to antitumor therapies.
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