ABSTRACT
Ingestion of Porphyromonas gingivalis, a periodontal pathogen, disrupts the intestinal barrier in mice. However, the involvement of outer membrane vesicles (OMVs) secreted from P. gingivalis in the destruction of the intestinal barrier remains unclear. In this study, we tested the hypothesis that OMVs carrying gingipains, the major cysteine proteases produced by P. gingivalis, affects the intestinal barrier function. OMVs increased the permeability of the Caco-2 cell monolayer, a human intestinal epithelial cell line, accompanied by degradation of the tight junction protein occludin. In contrast, OMVs prepared from mutant strains devoid of gingipains failed to induce intestinal barrier dysfunction or occludin degradation in Caco-2 cells. A close histological examination revealed the intracellular localization of gingipain-carrying OMVs. Gingipain activity was detected in the cytosolic fraction of Caco-2 cells after incubation with OMVs. These results suggest that gingipains were internalized into intestinal cells through OMVs and transported into the cytosol, where they then directly degraded occludin from the cytosolic side. Thus, P. gingivalis OMVs might destroy the intestinal barrier and induce systemic inflammation via OMV itself or intestinal substances leaked into blood vessels, causing various diseases.
Subject(s)
Adhesins, Bacterial , Porphyromonas gingivalis , Animals , Mice , Humans , Gingipain Cysteine Endopeptidases/metabolism , Caco-2 Cells , Porphyromonas gingivalis/physiology , Cytosol/metabolism , Occludin/metabolism , Adhesins, Bacterial/metabolismABSTRACT
Targeted alpha therapy (TAT) is a methodology that is being developed as a promising cancer treatment using the α-particle decay of radionuclides. This technique involves the use of heavy radioactive elements being placed near the cancer target area to cause maximum damage to the cancer cells while minimizing the damage to healthy cells. Using gold nanoparticles (AuNPs) as carriers, a more effective therapy methodology may be realized. AuNPs can be good candidates for transporting these radionuclides to the vicinity of the cancer cells since they can be labeled not just with the radionuclides, but also a host of other proteins and ligands to target these cells and serve as additional treatment options. Research has shown that astatine and iodine are capable of adsorbing onto the surface of gold, creating a covalent bond that is quite stable for use in experiments. However, there are still many challenges that lie ahead in this area, whether they be theoretical, experimental, and even in real-life applications. This review will cover some of the major developments, as well as the current state of technology, and the problems that need to be tackled as this research topic moves along to maturity. The hope is that with more workers joining the field, we can make a positive impact on society, in addition to bringing improvement and more knowledge to science.
Subject(s)
Astatine , Gold , Metal Nanoparticles , Gold/chemistry , Metal Nanoparticles/chemistry , Metal Nanoparticles/therapeutic use , Humans , Astatine/chemistry , Astatine/therapeutic use , Neoplasms/radiotherapy , Neoplasms/drug therapyABSTRACT
Zinc finger protein 335 (Zfp335) is a transcription factor that regulates mammalian neurogenesis and neuronal differentiation. It is a causative factor for severe microcephaly, small somatic size, and neonatal death. Here, we evaluated the effects of Zfp335 in the adult mouse brain after lipopolysaccharide (LPS) challenge. We used wild-type (WT) and Zfp335 knock-down (Zfp335+/- ) mice with LPS administered in the intracerebral ventricle in vivo and cultured microglia treated with LPS in vitro. The impact of Zfp335 was evaluated by RT-PCR, RNA-sequencing, western blotting, immunocytochemistry, ELISA, and the memory behavior tests. Knockdown of Zfp335 expression ameliorated microglia activation significantly, including reduced mRNA and protein expression of Iba1, reduced numbers of microglia, reduced cell diameter, and increased branch length, in the brains of 2-month-old mice after LPS treatment. Zfp335 was expressed in microglia and neurons, but increased in microglia, not neurons, in the brain of mice after LPS administration. LPS-induced microglia-mediated neurodegeneration was dependent upon microglial Zfp335 controlled by nuclear factor-kappa B. Microglial Zfp335 affected neuronal activity through transcriptional regulation of lymphocyte antigen-6M (Ly6M). Our data suggest that Zfp335 is a key transcription factor that exacerbates microglia-mediated neurodegeneration through upregulation of Ly6M expression. Inhibition of microglial Zfp335 may be a new strategy for preventing brain disease induced by microglia activation.
ABSTRACT
Papain-like cysteine proteases are composed of 11 human cysteine cathepsins, originally located in the lysosomes. They exhibit broad specificity and act as endopeptidases and/or exopeptidases. Among them, only cathepsins B, H, C, and X/Z exhibit exopeptidase activity. Recently, cysteine cathepsins have been found to be present outside the lysosomes and often participate in various pathological processes. Hence, they have been considered key signalling molecules. Their potentially hazardous proteolytic activities are tightly regulated. This review aims to discuss recent advances in understanding the structural aspects of these four cathepsins, mechanisms of their zymogen activation, regulation of their activities, and functional aspects of these enzymes in neurodegeneration and cancer. Neurodegenerative effects have been evaluated, particularly in Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, multiple sclerosis, and neuropsychiatric disorders. Cysteine cathepsins also participate in tumour progression and metastasis through the overexpression and secretion of proteases, which trigger extracellular matrix degradation. To our knowledge, this is the first review to provide an in-depth analysis regarding the roles of cysteine cathepsins B, H, C, and X in neurodegenerative diseases and cancer. Further advances in understanding the functions of cysteine cathepsins in these conditions will result in the development of novel, targeted therapeutic strategies.
Subject(s)
Cysteine Proteases , Neoplasms , Neurodegenerative Diseases , Humans , Cysteine/metabolism , Cathepsin B , Lysosomes/metabolismABSTRACT
Oral squamous cell carcinoma (OSCC) is the sixth most common cancer with a 5-year overall survival rate of 50%. Thus, there is a critical need to understand the disease process, and to identify improved therapeutic strategies. Previously, we found the long non-coding RNA (lncRNA) EGFR long non-coding downstream RNA (ELDR) induced in a mouse tongue cancer model; however, its functional role in human oral cancer remained unknown. Here, we show that ELDR is highly expressed in OSCC patient samples and in cell lines. Overexpression of ELDR in normal non-tumorigenic oral keratinocytes induces cell proliferation, colony formation, and PCNA expression. We also show that ELDR depletion reduces OSCC cell proliferation and PCNA expression. Proteomics data identifies the RNA binding protein ILF3 as an interacting partner of ELDR. We further show that the ELDR-ILF3 axis regulates Cyclin E1 expression and phosphorylation of the retinoblastoma (RB) protein. Intratumoral injection of ELDR-specific siRNA reduces OSCC and PDX tumor growth in mice. These findings provide molecular insight into the role of ELDR in oral cancer and demonstrate that targeting ELDR has promising therapeutic potential.
Subject(s)
Carcinoma, Squamous Cell , Mouth Neoplasms , RNA, Long Noncoding , Animals , Carcinoma, Squamous Cell/genetics , Cell Line, Tumor , Cell Proliferation/genetics , Humans , Mice , Mouth Neoplasms/genetics , RNA, Long Noncoding/geneticsABSTRACT
Recently, the effects of antibacterial peptides are suggested to have therapeutic potential in Alzheimer's disease. Furthermore, systemic treatment of Porphyromonas gingivalis (Pg) lipopolysaccharide (LPS) induced Alzheimer's disease-like neuropathological changes in middle-aged mice. Then, we examined whether human ß-defensins (hBDs), antimicrobial peptides produced by the oral mucosa and salivary glands, can suppress Pg LPS-induced oxidative and inflammatory responses by microglia. hBD3 (1 µM) significantly suppressed Pg LPS-induced production of nitric oxide and interleukin-6 (IL-6) by MG6 cells, a mouse microglial cell line. hBD3 (1 µM) also significantly inhibited Pg LPS-induced expression of IL-6 by HMC3 cells, a human microglial cell line. In contrast, neither hBD1, hBD2 nor hBD4 failed to inhibit their productions. Furthermore, hBD3 suppressed Pg LPS-induced p65 nuclear translocation through the IκBα degradation. Pg LPS-induced expression of IL-6 was significantly suppressed by E64d, a cysteine protease inhibitor, and CA-074Me, a known specific inhibitor for cathepsin B, but not by pepstatin A, an aspartic protease inhibitor. Interestingly, hBD3 significantly inhibited enzymatic activities of recombinant human cathepsins B and L, lysosomal cysteine proteases, and their intracellular activities in MG6 cells. Therefore, hBD3 suppressed oxidative and inflammatory responses of microglia through the inhibition of cathepsins B and L, which enzymatic activities are necessary for the NF-κB activation.
Subject(s)
Alzheimer Disease , beta-Defensins , Animals , Humans , Mice , beta-Defensins/metabolism , Cathepsin B/metabolism , Interleukin-6/metabolism , Lipopolysaccharides , Microglia/metabolism , NF-kappa B/metabolism , Porphyromonas gingivalis/metabolism , Cathepsin L/metabolismABSTRACT
BACKGROUND: Cathepsin H (CatH) is a lysosomal cysteine protease with a unique aminopeptidase activity. Its expression level is increased in activated immune cells including dendritic cells, macrophages, and microglia. We have previously reported that CatH deficiency impairs toll-like receptor 3 (TLR3)-mediated activation of interferon regulatory factor 3 (IRF3), and the subsequent secretion of interferon (IFN)-ß from dendritic cells. Furthermore, there is increasing evidence that IFN-ß secreted from microglia/macrophages has neuroprotective effects. These observations prompted further investigation into the effects of CatH deficiency on neuropathological changes. METHODS: In this study, neuropathological changes were examined using histochemical staining (both hematoxylin-eosin (H&E) and Nissl) of the hippocampus of wild-type (WT) and CatH-deficient (CatH-/-) mice after hypoxia-ischemia (HI). The density and the localization of CatH and TLR3 were examined by immunofluorescent staining. CatH processing in microglia was assayed by pulse-chase experiments, while immunoblotting was used to examine TLR3 expression and IRF3 activation in microglia/macrophages in the presence of poly(I:C). Microglial cell death was examined by fluorescence-activated cell sorting (FACS), and primary astrocyte proliferation in the presence of IFN-ß was examined using scratch wound assay. RESULTS: WT mice displayed severe atrophy in association with neuronal death and moderate astrogliosis in the hippocampus following neonatal HI. Somewhat surprisingly, CatH-/- mice showed marked neuronal death without severe atrophy in the hippocampus following HI. Furthermore, there was notable microglia/macrophages cell death and strong astrogliosis in the hippocampus. The TLR3 and phosphorylated IRF3 expression level in the hippocampus or splenocytes (mainly splenic macrophages); from CatH-/- mice was lower than in WT mice. In vitro experiments demonstrated that recombinant IFN-ß suppressed HI-induced microglial cell death and astrocyte proliferation. CONCLUSION: These observations suggest that CatH plays a critical role in the proteolytic maturation and stabilization of TLR3, which is necessary for IFN-ß production. Therefore, impaired TLR3/IFN-ß signaling resulting from CatH deficiency may induce microglial cell death after activation and astrogliosis/glial scar formation in the hippocampus following HI injury, leading to suppression of hippocampal atrophy.
Subject(s)
Cathepsin H/genetics , Hippocampus/pathology , Hypoxia-Ischemia, Brain/genetics , Interferon-beta/metabolism , Toll-Like Receptor 3/metabolism , Animals , Atrophy/genetics , Atrophy/metabolism , Atrophy/pathology , Cathepsin H/metabolism , Cell Death/physiology , Hippocampus/metabolism , Hypoxia-Ischemia, Brain/metabolism , Hypoxia-Ischemia, Brain/pathology , Interferon-beta/genetics , Mice , Mice, Knockout , Microglia/metabolism , Microglia/pathology , Signal Transduction/physiology , Toll-Like Receptor 3/geneticsABSTRACT
NO dissociation is an important reaction step in the NO reduction reaction, particularly in the three-way catalyst conversion system for automotive gas exhaust purification. In this study, we used first-principles calculations based on density functional theory to analyze the interaction and dissociation of NO on the PdRuIr ternary alloy. The electronic properties of the atomic combination of the PdRuIr ternary alloy create an effective catalyst that is active for NO dissociation and relatively stable against the formation of volatile RuOx through a weakened O adsorption. This study also shows that for an alloyed system, the strength of NO adsorption may not necessarily predict the dissociation activity. This tendency is observed in the PdRuIr ternary alloy where Ru top is the active site for NO adsorption albeit not an effective site for dissociation. It is presumed that NO dissociation is mediated by its molecular diffusion to active sites for dissociation, which are usually high Ru- and/or Ir-coordinated hollow or bridge sites. These active sites allow high charge transfer from the surface to NO, which fills the NO anti-bonding state and facilitates dissociation. This therefore assumes that the strength of NO molecular adsorption is not a descriptor for NO dissociation on metal alloys but rather the ability of the surface to transfer charge to NO and homogeneity of the strength of adsorption. Furthermore, O adsorption on the ternary alloy, particularly near the Ru sites, is relatively weaker as compared to the pure Ru surface. This weakened O adsorption is attributed to charge re-distribution through alloying, particularly charge transfer from the Ru atom to the Ir and Pd atoms.
ABSTRACT
Two types of melanin pigments, brown to black eumelanin and yellow to reddish brown pheomelanin, are biosynthesized through a branched reaction, which is associated with the key intermediate dopaquinone (DQ). In the presence of l-cysteine, DQ immediately binds to the -SH group, resulting in the formation of cysteinyldopa necessary for the pheomelanin production. l-Cysteine prefers to bond with aromatic carbons adjacent to the carbonyl groups, namely C5 and C2. Surprisingly, this Michael addition takes place at 1,6-position of the C5 (and to some extent at C2) rather than usually expected 1,4-position. Such an anomaly on the reactivity necessitates an atomic-scale understanding of the binding mechanism. Using density functional theory-based calculations, we investigated the binding of l-cysteine thiolate (Cys-S-) to DQ. Interestingly, the C2-S bonded intermediate was less energetically stable than the C6-S bonded case. Furthermore, the most preferred Cys-S--attacked intermediate is at the carbon-carbon bridge between the two carbonyls (C3-C4 bridge site) but not on the C5 site. This structure allows the Cys-S- to migrate onto the adjacent C5 or C2 with small activation energies. Further simulation demonstrated a possible conversion pathway of the C5-S (and C2-S) intermediate into 5-S-cysteinyldopa (and 2-S-cysteinyldopa), which is the experimentally identified major (and minor) product. Based on the results, we propose that the binding of Cys-S- to DQ proceeds via the following path: (i) coordination of Cys-S- to C3-C4 bridge, (ii) migration of Cys-S- to C5 (C2), (iii) proton rearrangement from cysteinyl -NH3+ to O4 (O3), and (iv) proton rearrangement from C5 (C2) to O3 (O4).
Subject(s)
Benzoquinones/chemistry , Cysteine/analogs & derivatives , Cysteinyldopa/chemistry , Dihydroxyphenylalanine/analogs & derivatives , Binding Sites , Cysteine/chemistry , Density Functional Theory , Dihydroxyphenylalanine/chemistry , Melanins/chemistry , Models, Molecular , ProtonsABSTRACT
We report novel PtW solid-solution nanoparticles (NPs) produced through electrochemical cleaning of core/shell PtW@WO3 NPs. The resulting PtW NPs achieved a record hydrogen evolution reaction (HER) performance as a class of Pt-based solid-solution alloys. A current density of 10 mA cm-2 was reached with an overpotential of 19.4 mV, which is significantly lower than that of a commercial Pt catalyst (26.3 mV). The PtW NPs also exhibited long-term stability. Theoretical calculations revealed that negatively charged Pt atoms adjacent to a W atom provide favorable hydrogen adsorption energies for the HER, realizing significantly enhanced HER activity.
ABSTRACT
Transition metal carbides have attractive physical and chemical properties that are much different from their parent metals. Particularly, noble metal carbides are expected to be promising materials for a variety of applications, particularly as efficient catalysts. However, noble metal carbides have rarely been obtained because carbide phases do not appear in noble metal-carbon phase diagrams and a reasonable synthesis method to make noble metal carbides has not yet been established. Here, we propose a new synthesis method for noble metal carbides and describe the first synthesis of rhodium carbide using tetracyanoethylene (TCNE). The rhodium carbide was synthesized without extreme conditions, such as the very high temperature and/or pressure typically required in conventional carbide syntheses. Moreover, we investigated the electronic structure and catalytic activity for the hydrogen evolution reaction (HER). We found that rhodium carbide has much higher catalytic activity for HER than pure Rh. Our study provides a feasible strategy to create new metal carbides to help advance the field of materials science.
ABSTRACT
The NLRP3 inflammasome is an intracellular innate immune sensor that is expressed in immune cells, including monocytes and macrophages. Activation of the NLRP3 inflammasome leads to IL-1ß secretion. Gain-of-function mutations of NLRP3 result in abnormal activation of the NLRP3 inflammasome, and cause the autosomal dominant systemic autoinflammatory disease spectrum, termed cryopyrin-associated periodic syndromes (CAPS). Here, we show that a missense mutation, p.Arg918Gln (c.2753G > A), of NLRP3 causes autosomal-dominant sensorineural hearing loss in two unrelated families. In family LMG446, hearing loss is accompanied by autoinflammatory signs and symptoms without serologic evidence of inflammation as part of an atypical CAPS phenotype and was reversed or improved by IL-1ß blockade therapy. In family LMG113, hearing loss segregates without any other target-organ manifestations of CAPS. This observation led us to explore the possibility that resident macrophage/monocyte-like cells in the cochlea can mediate local autoinflammation via activation of the NLRP3 inflammasome. The NLRP3 inflammasome can indeed be activated in resident macrophage/monocyte-like cells in the mouse cochlea, resulting in secretion of IL-1ß. This pathway could underlie treatable sensorineural hearing loss in DFNA34, CAPS, and possibly in a wide variety of hearing-loss disorders, such as sudden sensorineural hearing loss and Meniere's disease that are elicited by pathogens and processes that stimulate innate immune responses within the cochlea.
Subject(s)
Hearing Loss, Sensorineural/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , Adult , Animals , Base Sequence , Carrier Proteins/metabolism , Cochlea/metabolism , Cryopyrin-Associated Periodic Syndromes/genetics , Cryopyrin-Associated Periodic Syndromes/metabolism , Deafness/genetics , Family , Female , Hearing Loss , Hearing Loss, Sensorineural/metabolism , Humans , Inflammasomes/metabolism , Inflammation/metabolism , Interleukin 1 Receptor Antagonist Protein/metabolism , Interleukin 1 Receptor Antagonist Protein/pharmacology , Interleukin-1beta/antagonists & inhibitors , Interleukin-1beta/metabolism , Male , Mice , Mice, Knockout , Middle Aged , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/physiology , Pedigree , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/metabolism , Polymorphism, Single Nucleotide/geneticsABSTRACT
BACKGROUND: Disturbances in clock genes affect almost all patients with Alzheimer's disease (AD), as evidenced by their altered sleep/wake cycle, thermoregulation, and exacerbation of cognitive impairment. As microglia-mediated neuroinflammation proved to be a driver of AD rather than a result of the disease, in this study, we evaluated the relationship between clock gene disturbance and neuroinflammation in microglia and their contribution to the onset of AD. METHODS: In this study, the expression of clock genes and inflammatory-related genes was examined in MACS microglia isolated from 2-month-old amyloid precursor protein knock-in (APP-KI) and wild-type (WT) mice using cap analysis gene expression (CAGE) deep sequencing and RT-PCR. The effects of clock gene disturbance on neuroinflammation and relevant memory changes were examined in 2-month-old APP-KI and WT mice after injection with SR9009 (a synthetic agonist for REV-ERB). The microglia morphology was studied by staining, neuroinflammation was examined by Western blotting, and cognitive changes were examined by Y-maze and novel object recognition tests. RESULTS: CLOCK/BMAL1-driven transcriptional negative feedback loops were impaired in the microglia from 2-month-old APP-KI mice. Pro-inflammatory genes in microglia isolated from APP-KI mice were significantly higher than those isolated from WT mice at Zeitgeber time 14. The expression of pro-inflammatory genes was positively associated with NF-κB activation and negatively associated with the BMAL1 expression. SR9009 induced the activation of microglia, the increased expression of pro-inflammatory genes, and cognitive decline in 2-month-old APP-KI mice. CONCLUSION: Clock gene disturbance in microglia is involved in the early onset of AD through the induction of chronic neuroinflammation, which may be a new target for preventing or slowing AD.
Subject(s)
Amyloid beta-Protein Precursor/metabolism , Brain/metabolism , CLOCK Proteins/metabolism , Gene Knock-In Techniques/methods , Inflammation Mediators/metabolism , Microglia/metabolism , Amyloid beta-Protein Precursor/genetics , Animals , Brain/drug effects , CLOCK Proteins/antagonists & inhibitors , CLOCK Proteins/genetics , Inflammation/genetics , Inflammation/metabolism , Inflammation Mediators/agonists , Locomotion/drug effects , Locomotion/physiology , Mice , Mice, Inbred C57BL , Mice, Transgenic , Microglia/drug effects , Pyrrolidines/toxicity , Thiophenes/toxicityABSTRACT
OBJECTIVE: To identify novel autoantibodies for neuropathic pain (NeP). METHODS: We screened autoantibodies that selectively bind to mouse unmyelinated C-fiber type dorsal root ganglion (DRG) neurons using tissue-based indirect immunofluorescence assays (IFA) with sera from 110 NeP patients with various inflammatory and allergic neurologic diseases or other neuropathies, and 50 controls without NeP including 20 healthy subjects and 30 patients with neurodegenerative diseases or systemic inflammatory diseases. IgG purified from IFA-positive patients' sera was subjected to Western blotting (WB) and immunoprecipitation (IP) using mouse DRG lysates. Immunoprecipitates were analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS) to identify target autoantigens. RESULTS: Antiunmyelinated C-fiber type DRG neuron antibodies were more frequent in patients with NeP than non-NeP subjects (10% vs 0%; p < 0.05). These autoantibodies were all from the IgG2 subclass and colocalized mostly with isolectin B4- and P2X3-positive pain-conducting small neurons but not with S100ß-positive myelinated neurons. WB revealed a common immunoreactive band (approximately 220kDa). IP and LC-MS/MS studies identified plexin D1 as a target autoantigen. Immunoadsorption tests with recombinant human plexin D1 in IFA revealed that all 11 anti-small DRG neuron antibody-positive patients had anti-plexin D1 antibodies. Application of anti-plexin D1 antibody-positive patient sera to cultured DRG neurons increased membrane permeability, leading to cellular swelling. NeP patients with anti-plexin D1 antibodies commonly developed burning pain and current perception threshold abnormalities for C-fibers. Main comorbidities were atopy and collagen-vascular disease. Immunotherapies ameliorated NeP in 7 treated cases. INTERPRETATION: Anti-plexin D1 antibodies are a novel biomarker for immunotherapy-responsive NeP. Ann Neurol 2018;84:208-224.
Subject(s)
Autoantibodies/blood , Cell Adhesion Molecules, Neuronal/blood , Neuralgia/blood , Neuralgia/diagnosis , Adult , Aged , Animals , Biomarkers/blood , Cells, Cultured , Female , Ganglia, Spinal/metabolism , Ganglia, Spinal/pathology , HeLa Cells , Humans , Immunotherapy/methods , Intracellular Signaling Peptides and Proteins , Male , Membrane Glycoproteins , Mice , Mice, Inbred C57BL , Middle Aged , Neuralgia/therapy , Retrospective Studies , Young AdultABSTRACT
BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) represents one of the most common malignancies worldwide with a high mortality rate mainly due to lack of early detection markers, frequent association with metastasis and aggressive phenotype. Recently, long non-coding RNAs (lncRNAs) have been shown to have important regulatory roles in human cancers. The lncRNA prostate cancer-associated transcript 1 (PCAT-1) showed potential oncogenic roles in different cancers, however its role in HNSCC is not known. In this study, we evaluated the role of the PCAT-1 in HNSCC. METHODS: The expression of PCAT-1 was measured by quantitative real-time PCR in 23 paired human HNSCC tissues and adjacent non-tumor tissue specimens. Cell proliferation after depleting PCAT-1 was determined. Effect of PCAT-1 depletion in HNSCC cell lines was determined by qRT-PCR and Western blot analyses. Finally, JHU029 HNSCC cells was implanted subcutaneously into athymic nude mice and therapeutic potential of PCAT-1 was investigated. RESULTS: Up-regulation of PCAT-1 in TCGA dataset of HNSCC was noted. We also observed increased expression of PCAT-1 in archived HNSCC patient samples as compared to adjacent non-tumor tissues. Knockdown of PCAT-1 significantly reduced cell proliferation in HNSCC cell lines. Mechanistic study revealed significant down regulation of c-Myc and AKT1 gene in both RNA and protein levels upon knockdown of PCAT-1. We observed that c-Myc and AKT1 positively correlate with PCAT-1 expression in HNSCC. Further, we observed activation of p38 MAPK and apoptosis signal-regulating kinase 1 upon knockdown of PCAT-1 which induces Caspase 9 and PARP mediated apoptosis. Targeted inhibition of PCAT-1 regresses tumor growth in nude mice. CONCLUSION: Together our data demonstrated an important role of the PCAT-1 in HNSCC and might serve as a target for HNSCC therapy.
Subject(s)
Apoptosis/genetics , Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Proto-Oncogene Proteins c-myc/metabolism , RNA, Long Noncoding/genetics , p38 Mitogen-Activated Protein Kinases/metabolism , Animals , Cell Line, Tumor , Cell Proliferation , Disease Models, Animal , Gene Expression Regulation, Neoplastic , Gene Knockdown Techniques , Heterografts , Humans , Mice , Signal TransductionABSTRACT
Following publication of the original article [1], it was reported that Fig. 1c was not entirely readable due to overlapping Fig. 1d. The publishers apologise for this error.
ABSTRACT
BACKGROUND: Metabolic reprogramming is one of the hallmarks of cancer which favours rapid energy production, biosynthetic capabilities and therapy resistance. In our previous study, we showed bitter melon extract (BME) prevents carcinogen induced mouse oral cancer. RNA sequence analysis from mouse tongue revealed a significant modulation in "Metabolic Process" by altering glycolysis and lipid metabolic pathways in BME fed group as compared to cancer group. In present study, we evaluated the effect of BME on glycolysis and lipid metabolism pathways in human oral cancer cells. METHODS: Cal27 and JHU022 cells were treated with BME. RNA and protein expression were analysed for modulation of glycolytic and lipogenesis genes by quantitative real-time PCR, western blot analyses and immunofluorescence. Lactate and pyruvate level was determined by GC/MS. Extracellular acidification and glycolytic rate were measured using the Seahorse XF analyser. Shotgun lipidomics in Cal27 and JHU022 cell lines following BME treatment was performed by ESI/ MS. ROS was measured by FACS. RESULTS: Treatment with BME on oral cancer cell lines significantly reduced mRNA and protein expression levels of key glycolytic genes SLC2A1 (GLUT-1), PFKP, LDHA, PKM and PDK3. Pyruvate and lactate levels and glycolysis rate were reduced in oral cancer cells following BME treatment. In lipogenesis pathway, we observed a significant reduction of genes involves in fatty acid biogenesis, ACLY, ACC1 and FASN, at the mRNA and protein levels following BME treatment. Further, BME treatment significantly reduced phosphatidylcholine, phosphatidylethanolamine, and plasmenylethanolamine, and reduced iPLA2 activity. Additionally, BME treatment inhibited lipid raft marker flotillin expression and altered its subcellular localization. ER-stress associated CHOP expression and generation of mitochondrial reactive oxygen species were induced by BME, which facilitated apoptosis. CONCLUSION: Our study revealed that bitter melon extract inhibits glycolysis and lipid metabolism and induces ER and oxidative stress-mediated cell death in oral cancer. Thus, BME-mediated metabolic reprogramming of oral cancer cells will have important preventive and therapeutic implications along with conventional therapies.
Subject(s)
Antineoplastic Agents/pharmacology , Glycolysis/drug effects , Lipogenesis/drug effects , Metabolic Networks and Pathways/drug effects , Momordica charantia/chemistry , Mouth Neoplasms/pathology , Plant Extracts/pharmacology , Cell Line, Tumor , Gene Expression Regulation, Neoplastic/drug effects , Humans , Mouth Neoplasms/metabolism , Reactive Oxygen Species/metabolism , Transcription Factor CHOP/metabolismABSTRACT
BACKGROUND: Infants admitted to the neonatal intensive care unit (NICU) have a higher incidence of congenital hearing loss compared with the healthy newborn population. OBJECTIVES: To clarify the relationship between risk factors for hearing impairment in NICU-treated infants and deterioration of the auditory brainstem response (ABR) threshold during childhood. METHOD: We screened 1,071 high-risk infants admitted to the NICU for hearing impairment. One-hundred forty-eight infants exhibited an abnormal ABR threshold of ≥40 dB nHL. We analyzed the correlation of change in ABR threshold with risk factors for future hearing impairment. RESULTS: Among infants treated in the NICU, 148 (13.8%) exhibited an ABR threshold of ≥40 dB nHL; 107 of these 148 (72.3%) showed hearing change in the process (102 showed improvement to normal hearing level, whereas 5 showed further deterioration). Our analysis showed that the factors contributing to the elevation of ABR threshold were oxygen administration and chromosomal aberrations. CONCLUSIONS: Factors related to the elevation of ABR threshold were oxygen administration and the presence of chromosomal aberrations. Awareness of risk factors that are more likely to cause hearing loss in infants may aid in follow-up treatment of these children.
Subject(s)
Hearing Loss/congenital , Intensive Care Units, Neonatal , Child , Chromosome Aberrations , Cross-Sectional Studies , Evoked Potentials, Auditory, Brain Stem/physiology , Female , Gestational Age , Hearing Loss/diagnosis , Hearing Loss/epidemiology , Hearing Loss/rehabilitation , Humans , Incidence , Infant , Infant, Newborn , Japan , Male , Neonatal Screening , Oxygen Inhalation Therapy/adverse effects , Prognosis , Risk FactorsABSTRACT
The CA3 subregion of the hippocampus is important for rapid encoding, storage and retrieval of associative memories. Lesions and pharmacological inhibitions of hippocampal CA3 suggest that it is essential for different memories. However, how CA3 functions in spatial and episodic memory in different time scales (i.e. short-term versus long term) without permanent lesions has not been systematically investigated yet. Taking advantage of the chemogenetic access to opsins, this study used luminopsins, fusion proteins of luciferase and optogenetic elements, to manipulate neuronal activity in CA3 during memory tasks over a range of spatial and temporal scales. In this study, we found that excitation or inhibition of CA3 neurons had no significant effects on long-term spatial or episodic memory, but had remarkable effects on spatial working memory, spatial short-term memory as well as episodic short-term memory. In addition, stimulation of CA3 neurons altered the expression levels of NR2A. Intracerebral injection of receptor inhibitors further confirmed that NR2A is crucial to spatial working memory, which is consistent with the luminopsins experiments. These findings indicate that CA3 maintains a specific role on spatial and episodic memory over a short period of time.
Subject(s)
CA3 Region, Hippocampal/physiology , Memory, Episodic , Neurons/physiology , Spatial Memory/physiology , Animals , Memory, Long-Term/physiology , Memory, Short-Term/physiology , Mice, Inbred C57BL , Opsins , OptogeneticsABSTRACT
OBJECTIVE: The objective of this study is to investigate the role of cathepsin H (CatH), a lysosomal cysteine protease, in the development of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis. METHODS: EAE was induced in CatH-deficient mice (CatH-/-) and wild-type littermates (+/+) using myelin oligodendrocyte glycoprotein (MOG) 35-55. The effects of CatH deficiency were determined by clinical scoring, mRNA expression levels of Tbx21, Rorc and FoxP3, protein levels of poly(I:C)-induced toll-like receptor 3 (TLR3) and phosphorylation of IRF3, and secretion of interferon-ß (IFN-ß) by splenocytes. RESULTS AND CONCLUSIONS: CatH-/- showed a significantly earlier disease onset of EAE and increased Th1 cell differentiation in splenocytes. Splenocytes prepared from immunized CatH-/- showed a significant decrease in poly(I:C)-induced increased TLR3 expression, interferon regulatory factor 3 (IRF3) phospholylation and IFN-ß secretion. Therefore, CatH deficiency impaired TLR3-mediated activation of IRF3 and consequent secretion of IFN-ß from dendritic cells, leading to the enhancement of Th1 cell differentiation and consequent early disease onset of EAE.