ABSTRACT
Glycogen synthase kinase-3 (GSK-3) is a critical molecule in Alzheimer's disease (AD) that modulates two histopathological hallmarks of AD: Amyloid beta (Aß) plaques and neurofibrillary tangles composed of aberrant hyper-phosphorylation of tau protein. This study was performed to investigate the protective effect of flavone apigenin through inhibition of GSK-3 and the involvement of this kinase in the inhibition of BACE1 expression and hyperphosphorylation of tau protein in an AD rat model. 15 nM of aggregated amyloid-beta 25-35 was microinjected into the left lateral ventricle of an AD rat. Apigenin (50 mg/kg) was administered orally 45 min before the Aß injection and continued daily for three weeks. Immunohistochemistry and western blot analysis showed that apigenin significantly reduced the hyperphosphorylation of tau levels in the hippocampus. Real-time PCR analysis revealed significant inhibition of the mRNA level of ß secretase (BACE1) and GSK-3ß, but Apigenin had no effect on the level of GSK-3α. The results demonstrate that apigenin has a protective effect against amyloid-beta 25-35 by decreasing the expression of GSK-3ß with the consequence of lowering the hyperphosphorylation of tau protein and suppressing BACE1 expression.
Subject(s)
Alzheimer Disease/genetics , Alzheimer Disease/prevention & control , Amyloid beta-Peptides/antagonists & inhibitors , Amyloid beta-Peptides/toxicity , Apigenin/pharmacology , Glycogen Synthase Kinase 3 beta/drug effects , Neuroprotective Agents/pharmacology , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/toxicity , Amyloid Precursor Protein Secretases/biosynthesis , Amyloid Precursor Protein Secretases/genetics , Animals , Aspartic Acid Endopeptidases/biosynthesis , Aspartic Acid Endopeptidases/genetics , Immunohistochemistry , Male , Phosphorylation , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Rats , Rats, Wistar , tau Proteins/metabolismABSTRACT
Background: Novel aspartic proteinase of the pepsin family A (Napsin A, TAO1/TAO2) is a functional aspartic proteinase which is involved in the maturation of prosurfactant protein B in type II pneumocytes and the lysosomal protein catabolism in renal cells. Napsin A is highly expressed in adenocarcinomas of the lung and is thus commonly used to affirm this diagnosis. However, studies have shown that other tumors can also express Napsin A. Methods: To comprehensively determine Napsin A expression in normal and tumor tissue, 11,957 samples from 115 different tumor types and subtypes as well as 500 samples of 76 different normal tissue types were evaluable by immunohistochemistry on tissue microarrays. Results: Napsin A expression was present in 16 different tumor types. Adenocarcinoma of the lung (85.6%), clear cell adenocarcinoma of the ovary (71.7%), clear cell adenocarcinoma of the endometrium (42.8%), papillary renal cell carcinoma (40.2%), clear cell (tubulo) papillary renal cell carcinoma (16.7%), endometrial serous carcinoma (9.3%), papillary thyroid carcinoma (9.3%) and clear cell renal cell carcinoma (8.2%) were among the tumors with the highest prevalence of Napsin A positivity. In papillary and clear cell renal cell carcinoma, reduced Napsin A expression was linked to adverse clinic-pathological features (p ≤ 0.03). Conclusion: This methodical approach enabled us to identify a ranking order of tumors according to their relative prevalence of Napsin A expression. The data also show that loss of Napsin A is linked to tumor dedifferentiation in renal cell carcinomas.
Subject(s)
Aspartic Acid Endopeptidases/analysis , Aspartic Acid Endopeptidases/biosynthesis , Biomarkers, Tumor/metabolism , Neoplasms/metabolism , HumansABSTRACT
Accumulation of amyloid-ß (Aß) in the brain is a central component of pathology in Alzheimer's disease. A growing volume of evidence demonstrates close associations between periodontal pathogens including Porphyromonas gingivalis (P. gingivalis) and Treponema denticola (T. denticola) and AD. However, the effect and mechanisms of T. denticola on accumulation of Aß remain to be unclear. In this study, we demonstrated that T. denticola was able to enter the brain and act directly on nerve cells resulting in intra- and extracellular Aß1-40 and Aß1-42 accumulation in the hippocampus of C57BL/6 mice by selectively activating both ß-secretase and γ-secretase. Furthermore, both KMI1303, an inhibitor of ß-secretase, as well as DAPT, an inhibitor of γ- secretase, were found to be able to inhibit the effect of T. denticola on Aß accumulation in N2a neuronal cells. Overall, it is concluded that T. denticola increases the expression of Aß1-42 and Aß1-40 by its regulation on beta-site amyloid precursor protein cleaving enzyme-1 and presenilin 1.
Subject(s)
Amyloid beta-Peptides/biosynthesis , Hippocampus/metabolism , Mouth/microbiology , Peptide Fragments/biosynthesis , Treponema denticola/pathogenicity , Treponemal Infections/metabolism , Amyloid Precursor Protein Secretases/antagonists & inhibitors , Amyloid Precursor Protein Secretases/biosynthesis , Amyloid Precursor Protein Secretases/genetics , Amyloid Precursor Protein Secretases/metabolism , Animals , Aorta/microbiology , Aspartic Acid Endopeptidases/biosynthesis , Aspartic Acid Endopeptidases/genetics , Diamines/pharmacology , Enzyme Activation , Hippocampus/microbiology , Male , Mice , Mice, Inbred C57BL , Neurons/metabolism , Neurons/microbiology , Porphyromonas gingivalis/pathogenicity , Presenilin-1/biosynthesis , Presenilin-1/genetics , Random Allocation , Thiazoles/pharmacology , Treponemal Infections/pathology , Trigeminal Ganglion/metabolism , Trigeminal Ganglion/microbiologyABSTRACT
Alzheimer's disease (AD) is a major public health crisis due to devastating cognitive symptoms, a lack of curative treatments, and increasing prevalence. Most cases are sporadic (>95% of cases) after the age of 65 years, implicating an important role of environmental factors in disease pathogenesis. Environmental neurotoxicants have been implicated in neurodegenerative disorders including Parkinson's Disease and AD. Animal models of AD and in vitro studies have shed light on potential neuropathological mechanisms, yet the biochemical and molecular underpinnings of AD-relevant environmental neurotoxicity remain poorly understood. Beta-site amyloid precursor protein cleaving enzyme 1 (BACE1) is a potentially critical pathogenic target of environmentally induced neurotoxicity. BACE1 clearly has a critical role in AD pathophysiology: It is required for amyloid beta production and expression and activity of BACE1 are increased in the AD brain. Though the literature on BACE1 in response to environmental insults is limited, current studies, along with extensive AD neurobiology literature suggest that BACE1 deserves attention as an important neurotoxic target. Here, we critically review research on environmental neurotoxicants such as metals, pesticides, herbicides, fungicides, polyfluoroalkyl substances, heterocyclic aromatic amines, advanced glycation end products, and acrolein that modulate BACE1 and potential mechanisms of action. Though more research is needed to clearly understand whether BACE1 is a critical mediator of AD-relevant neurotoxicity, available reports provide convincing evidence that BACE1 is altered by environmental risk factors associated with AD pathology, implying that BACE1 inhibition and its use as a biomarker should be considered in AD management and research.
Subject(s)
Alzheimer Disease , Amyloid Precursor Protein Secretases/biosynthesis , Aspartic Acid Endopeptidases/biosynthesis , Brain/enzymology , Environmental Exposure/adverse effects , Gene Expression Regulation, Enzymologic , Neurotoxicity Syndromes , Neurotoxins/toxicity , Aged , Alzheimer Disease/enzymology , Alzheimer Disease/etiology , Alzheimer Disease/pathology , Animals , Brain/pathology , Disease Models, Animal , Female , Humans , Male , Neurotoxicity Syndromes/enzymology , Neurotoxicity Syndromes/etiology , Neurotoxicity Syndromes/pathologyABSTRACT
Coxsackie B3 virus (CVB3) is a member of small RNA viruses that belongs to the genus Enterovirus of the family Picornaviridae and CVB3 is the main pathogen of acute and chronic viral myocarditis. In this study RT-qPCR was used to determine the expression of miR-107 in CVB3-infected and uninfected HeLa cells. The experimental results show that the level of miR-107 began to rise at 4 h after the infection, and significantly boosted at 6 h. Based on the results of this experiment, we consider that miR-107 expression is related to CVB3 infection. In order to further clarify the effect of miR-107 in the process of CVB3 infection, we studied the effect of miR-107 upstream and downstream target genes on CVB3 replication. Levels of the target RNAs were detected by RT-qPCR after CVB3 infection, and the expression of CVB3 capsid protein VP1 by western blot analysis. Then the virus in the supernatant was quantitated via a viral plaque assay, reflecting the release of the virus. The experimental results showed that miRNA-107 expression is associated with CVB3 replication and proliferation, while KLF4 and BACE1 as the downstream of miR-107 weakened CVB3 replication. Overexpressions of KLF4 and BACE1 negatively regulated CVB3 replication, this effect on CVB3 was completely opposite to that of miR-107. Further experiments revealed that the upstream lncRNA004787, a new lncRNA that had not been reported, was located on chromosome 5, strand - from 37073250 to 37070908 (genome assembly: hg19). We sequenced and studied lncRNA004787 and found that it partially inhibited CVB3 replication. This prompted us to speculate that lncRNA004787 probably impacted the replication by other means. In conclusion, miR-107 interfered with CVB3 replication and release.
Subject(s)
Enterovirus/genetics , MicroRNAs/genetics , Virus Replication/genetics , Amyloid Precursor Protein Secretases/biosynthesis , Amyloid Precursor Protein Secretases/genetics , Animals , Aspartic Acid Endopeptidases/biosynthesis , Aspartic Acid Endopeptidases/genetics , Chromosomes, Human, Pair 5/genetics , HeLa Cells , Humans , Kruppel-Like Factor 4 , Kruppel-Like Transcription Factors/biosynthesis , Kruppel-Like Transcription Factors/genetics , RNA, Long Noncoding/genetics , RNA, Viral/biosynthesis , RNA, Viral/genetics , Viral Plaque AssayABSTRACT
Melatonin is a tryptophan metabolite synthesized by the pineal gland. Recent research showed that melatonin has a protective effect in Alzheimer's disease (AD). However, its exact mechanism is still unclear. This study was designed to investigate the effects of long-term oral melatonin on spatial learning and memory, Aß deposition and soluble Aß levels, amyloidogenic amyloid precursor protein (APP) processing, mitochondrial structure and mitophagy in APP/PS1 transgenic mice, a model of AD. The spatial learning and memory ability of mice were examined by using the Morris water maze. Thioflavin S staining was used to observe Aß deposition. ELISA was used to evaluate the levels of Aß40 and Aß42. The expression levels of mitophagy proteins (PINK1, Parkin, LC3-II and LC3-I) and amyloidogenic APP processing proteins (BACE1, APP and CTFß) were examined by western blotting analysis. Finally, transmission electron microscopy was used to observe mitochondrial structure and mitophagy vesicles. Our results showed that APP/PS1 transgenic mice with long-term oral melatonin showed improved spatial learning, alleviated memory impairment, reduced Aß deposition and restrained damage of mitochondrial structure. In addition, the number of mitophagy vesicles and expression levels of mitophagy factors (PINK1, Parkin, LC3-II/LC3-I) were decreased, as was the expression levels of amyloidogenic APP processing proteins (BACE1, APP and CTFß). Long-term oral melatonin decreased Aß deposition and improved spatial learning and memory in APP/PS1 transgenic mice by a mechanism associated with down-regulation of BACE1 and mitophagy.
Subject(s)
Amyloid Precursor Protein Secretases/biosynthesis , Aspartic Acid Endopeptidases/biosynthesis , Brain/pathology , Maze Learning/drug effects , Melatonin/pharmacology , Neuroprotective Agents/pharmacology , Alzheimer Disease , Amyloid beta-Peptides/metabolism , Amyloid beta-Protein Precursor/genetics , Animals , Brain/drug effects , Brain/metabolism , Down-Regulation , Humans , Male , Memory Disorders , Mice , Mice, Inbred C57BL , Mice, Transgenic , Mitophagy/drug effectsABSTRACT
Recent studies have showed that the long non-coding RNAs (lncRNAs) expression is dysregulated in different neurodegenerative disorders like Alzheimer's disease (AD). In the present study, the effects of memantine on the level of Bace1-as and Bace1 genes' expression in streptozotocin (STZ)-induced Alzheimer's and memantine treated rats were investigated. The male Wistar rats were randomly divided into four groups: 1-Normal control, 2-Sham-operated control, 3- Alzheimer'scontrol rats (ICV-STZ), 4-Experimental group rats treated by memantine in a dose of 30 mg/kg/day for 28 days in ICV-STZ rats. The expression of Bace1-as and Bace1 genes was measured by quantitative-PCR in the brain and blood tissues. ELISA was used to analyze Bace1 and Aß proteins. Expression of Bace1-as was significantly increased in the brain and blood tissues of the experimental group (p = 0.032 and p = 0.034, respectively). The expression of Bace1 gene showed no significant changes in the brain. Furthermore, the ELISA analysis revealed that Bace1 protein was significantly increased in the plasma of the Alzheimer's control group (p = 0.000) and in the brain tissue of the experimental group (p = 0.000). Additionally, Aß levels had no significant changes between all groups studied. The Bace1 protein may be used as a prognostic biomarker in plasma, or before using memantine as a treatment. Furthermore, Bace1-as gene expression may play a role in monitoring the progression of AD.
Subject(s)
Alzheimer Disease/drug therapy , Alzheimer Disease/genetics , Amyloid Precursor Protein Secretases/biosynthesis , Aspartic Acid Endopeptidases/biosynthesis , Memantine/pharmacology , RNA, Long Noncoding/genetics , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Amyloid Precursor Protein Secretases/genetics , Amyloid Precursor Protein Secretases/metabolism , Amyloid beta-Peptides/metabolism , Animals , Antiparkinson Agents/pharmacology , Aspartic Acid Endopeptidases/genetics , Aspartic Acid Endopeptidases/metabolism , Biomarkers/metabolism , Brain/drug effects , Brain/metabolism , Brain/pathology , Disease Models, Animal , Gene Expression/drug effects , Hippocampus/drug effects , Hippocampus/metabolism , Hippocampus/pathology , Male , Maze Learning/drug effects , RNA, Long Noncoding/biosynthesis , RNA, Long Noncoding/metabolism , Random Allocation , Rats , Rats, Wistar , Streptozocin/administration & dosageABSTRACT
BACKGROUND: It is believed that there is a certain correlation between the brain and kidneys, but it is poorly understood. Many findings suggested that there were previously unknown signaling pathways involving AßPP and BACE1 in the kidney. OBJECTIVE: Exploring the changes of BACE1 activity in APP23 mouse kidneys, providing evidence for the function of AßPP and BACE1 activity in the kidney. METHODS: The activity and expression of BACE1 were detected in the kidney of APP23 mice by enzymatic assay and western blotting. The protein expression levels of AßPP, claudin1, occludin, VE-cadherin, and Klotho (membrane-form klotho) were examined by using western blotting. The renal pathological changes of APP23 mice were examined by the routine renal pathological procedures. RESULTS: In this study, we found that the AßPP protein level was increased in kidneys of APP23 mice compared with wild-type (WT) mice. Additionally, the activity and expression of BACE1 were increased in kidneys of APP23 mice compared to that of WT. BACE1 was predominantly distributed on the lumen side of renal tubular epithelial cells. The protein levels of Klotho and VE-cadherin were decreased, occludin expression was also decreased, and claudin-1 expression was increased. Renal pathological damage which observed in kidneys of APP23 mice was more serious than that in kidneys of WT mice. CONCLUSION: Our findings suggest that the increase of AßPP protein levels under Thy-1 neuron promoter in the APP23 mice promoted the increase of renal BACE1 expression and enzymatic activity in the kidneys. Moreover, certain pathological damage in the kidneys of APP23 mice were observed. APP23 mice are easily affected by external risk factors compared with WT mice.
Subject(s)
Alzheimer Disease/metabolism , Amyloid Precursor Protein Secretases/biosynthesis , Amyloid beta-Protein Precursor/biosynthesis , Aspartic Acid Endopeptidases/biosynthesis , Brain/metabolism , Kidney/metabolism , Alzheimer Disease/genetics , Alzheimer Disease/pathology , Amyloid Precursor Protein Secretases/genetics , Amyloid beta-Protein Precursor/genetics , Animals , Aspartic Acid Endopeptidases/genetics , Brain/pathology , HEK293 Cells , Humans , Kidney/pathology , Mice , Mice, TransgenicABSTRACT
Significant advances in targeted therapy have been made in recent years for patients with lung adenocarcinoma. These targeted therapies have made molecular testing of paramount importance to drive therapeutic decisions. Material for testing is often limited, particularly in cytology specimens and small core biopsies. A reliable screening tool is invaluable in triaging limited tissue and selection for epidermal growth factor receptor (EGFR) mutation testing. We hypothesized that the immunohistochemistry (IHC) profile of lung adenocarcinoma predicts EGFR mutation status. In this retrospective study, we evaluated the thyroid transcription factor-1 (TTF-1)/napsin A IHC profile and EGFR mutation status in 339 lung adenocarcinomas at our academic institution. In our cohort, we found that 92.3% of cases were positive for TTF-1 and/or napsin A by IHC with an EGFR positivity rate of 17.3%. Importantly, 7.7% of the cases were dual TTF-1/napsin A negative, and none of these cases contained EGFR mutations. This finding supports the use of TTF-1 and napsin A IHC to identify cases where EGFR mutation status will be negative, thus preserving limited tissue for other ancillary testing.
Subject(s)
Adenocarcinoma of Lung/genetics , Aspartic Acid Endopeptidases/biosynthesis , Biomarkers, Tumor/analysis , Lung Neoplasms/genetics , Thyroid Nuclear Factor 1/biosynthesis , Aspartic Acid Endopeptidases/analysis , ErbB Receptors/genetics , Humans , Immunohistochemistry , Mutation , Retrospective Studies , Thyroid Nuclear Factor 1/analysisABSTRACT
This study reports the optimization of milk-clotting protease production from Aspergillus oryzae DRDFS13 under solid-state fermentation (SSF) in both one-variable-at-a-time and response surface methodology (RSM). The production and optimization of milk-clotting protease obtained from Aspergillus oryzae DRDFS13 under solid-state fermentation (SSF) using different agro-industrial wastes as solid substrates were studied. The agro-industrial wastes used included wheat bran, rice bran, pea bran, and grass pea bran. The chemical composition of the best solid substrate was tested using standard methods. Others cultivation parameters were studied, and the results showed that the optimum fermentation medium composed of wheat bran, casein (1% w/w), and glucose (0.5% w/w) and the conditions for maximum milk-clotting protease production were at the moisture content of 55.0%, inoculum of 0.5*106 spores/mL, incubation temperature of 30 °C, pH of 6.0, and fermentation time of 5 days. The highest milk-clotting activity was obtained from the crude enzyme extracted using 0.1 M NaCl and partial purification of the crude enzyme using chilled acetone, and 80% (NH4)2SO4 increased the ratio of MCA/PA from 0.56 to 1.30 and 0.65, respectively. Moreover, the highest MCA (137.58 U/mL) was obtained at a casein concentration of 0.5%, pH 4.0, and 25 °C, using RSM. Thus, results from the present study showed that the optimization of milk-clotting protease production from A. oryzae DRDFS 13 under SSF by both one-variable-at-a-time and RSM significantly increased the milk-clotting activity. This is the first report from a fungus in the Ethiopian setting and a modest contribution to highlight the potential of harnessing microbial protease enzymes for industrial applications.
Subject(s)
Aspartic Acid Endopeptidases/biosynthesis , Aspergillus oryzae/enzymology , Aspergillus oryzae/growth & development , Culture Media/chemistry , Fermentation , Fungal Proteins/biosynthesis , Hydrogen-Ion Concentration , Industrial Microbiology , TemperatureABSTRACT
Alzheimer's disease (AD) is one of the most common neurodegenerative diseases, and no effective therapies have been found to prevent or cure AD to date. Berberine and curcumin are extracts from traditional Chinese herbs that have a long history of clinical benefits for AD. Here, using a transgenic AD mouse model, we found that the combined berberine and curcumin treatment had a much better effect on improving the cognitive function of mice than the single-drug treatment, suggesting synergic effects of the combined berberine and curcumin treatment. In addition, we found that the combined berberine and curcumin treatment had significant synergic effects on reducing soluble amyloid-ß-peptide(1-42) production. Furthermore, the combination treatment also had remarkable synergic effects on decreasing inflammatory responses and oxidative stress in both the cortex and hippocampus of AD mice. We also found that the combination treatment performed much better than the single drugs in reducing the APP and BACE1 levels and increasing AMPKα phosphorylation and cell autophagy, which might be the underlying mechanism of the synergic effects. Taken together, the result of this study reveal the synergic effects and potential underlying mechanisms of the combined berberine and curcumin treatment in improving the symptoms of AD in mice. This study sheds light on a new strategy for exploring new phytotherapies for AD and also emphasizes that more research should focus on the synergic effects of herbal drugs in the future.
Subject(s)
Alzheimer Disease/drug therapy , Berberine/administration & dosage , Brain/drug effects , Cognition/drug effects , Curcumin/administration & dosage , Oxidative Stress/drug effects , Alzheimer Disease/genetics , Alzheimer Disease/metabolism , Amyloid Precursor Protein Secretases/antagonists & inhibitors , Amyloid Precursor Protein Secretases/biosynthesis , Amyloid beta-Peptides/antagonists & inhibitors , Amyloid beta-Peptides/biosynthesis , Animals , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Aspartic Acid Endopeptidases/antagonists & inhibitors , Aspartic Acid Endopeptidases/biosynthesis , Brain/metabolism , Cognition/physiology , Drug Synergism , Female , Male , Mice , Mice, Transgenic , Oxidative Stress/physiology , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/biosynthesisABSTRACT
Napsin A is widely used in the diagnosis of lung adenocarcinoma and has also been reported to be positive in cases of thyroid carcinomas. We investigated napsin A levels through immunohistochemistry on whole sections of 210 primary thyroid tumors of various subtypes and another 41 metastatic thyroid carcinomas, and compared these with 125 primary and 25 metastatic lung adenocarcinomas. The results showed that napsin A was expressed in 23.8% thyroid tumors and 30.3% papillary thyroid carcinomas. Most cases showed a focal and weak to moderate expression. In comparison, 80.8% primary lung adenocarcinomas expressed napsin A, with mostly diffused and strong expression. For metastatic carcinomas of thyroid and lung origin, napsin A was detected in 39.0% of thyroid carcinomas in contrast to 88.0% in cases of lung adenocarcinomas. Comparisons of additional markers, TTF-1, CK7, thyroglobulin, and Pax-8 in metastatic carcinomas showed the overlapping expression of immunomarkers of TTF-1 and CK7. Thyroglobulin and Pax-8 were useful for distinguishing between metastatic carcinomas; however, Pax-8 may be a superior marker due to its higher sensitivity. The clinicopathological analysis of papillary thyroid carcinomas showed that the expression of napsin A was positively correlated with lymph node metastasis (p = 0.030). Here, we focused on the expression of napsin A in thyroid tumors and compared it with that in lung adenocarcinomas. The expression of napsin A is common in thyroid tumors and the combined expression of napsin A and TTF-1 in a metastatic thyroid carcinoma is a cause for concern due to chances of misdiagnosis as lung adenocarcinoma.
Subject(s)
Adenocarcinoma of Lung/diagnosis , Aspartic Acid Endopeptidases/biosynthesis , Biomarkers, Tumor/analysis , Lung Neoplasms/diagnosis , Thyroid Neoplasms/diagnosis , Aspartic Acid Endopeptidases/analysis , Diagnosis, Differential , HumansABSTRACT
Neuroinflammation is involved in the pathogenesis of Alzheimer's disease, and the transcription factor NF-κB is a player in this event. We found here that the ischemic damage alone or in association with Aß1-42 activates the NF-κB pathway, induces an increase of BACE1 and a parallel inhibition of Uch-L1 and TREM2, both in vitro and in vivo, in Tg 5XFAD and in human brains of sporadic AD. This mechanism creates a synergistic loop that fosters inflammation. We also demonstrated a significant protection exerted by the restoration of Uch-L1 activity. The rescue of the enzyme is able to abolish the decrease of TREM2 and the parameters of neuroinflammation.
Subject(s)
Amyloid beta-Peptides/metabolism , Inflammation/metabolism , Membrane Glycoproteins/metabolism , Peptide Fragments/metabolism , Receptors, Immunologic/metabolism , Stroke/metabolism , Ubiquitin Thiolesterase/metabolism , Aged , Aged, 80 and over , Amyloid Precursor Protein Secretases/biosynthesis , Amyloid Precursor Protein Secretases/genetics , Animals , Aspartic Acid Endopeptidases/biosynthesis , Aspartic Acid Endopeptidases/genetics , Brain Ischemia/complications , Brain Ischemia/genetics , Brain Ischemia/metabolism , Cells, Cultured , Cytokines/biosynthesis , Down-Regulation , Female , Humans , Inflammation/etiology , Male , Mice , NF-kappa B/metabolism , Neurons/metabolism , Stroke/complications , Stroke/geneticsABSTRACT
BACKGROUND: The Arias-Stella reaction (ASR) can mimic endometrial clear cell carcinoma (ECCC) in small biopsies, especially when drug or pregnancy history is unknown. A panel of immunohistochemical markers comprising napsin A, hepatocyte nuclear factor-1-beta (HNF-1ß), estrogen and progesterone receptors (ER, PR) has been found useful in confirming a diagnosis of ECCC. However, the detailed characterization of how expression of this combination of markers in the ECCC mimics ASR has yet to be thoroughly evaluated. DESIGN: The frequency and extent of napsin A, HNF-1ß, ER, and PR expression in ASR were assessed in a large series. For napsin A, any cytoplasmic staining was considered positive while only nuclear staining was deemed to be positive for HNF-1ß, ER, and PR. Immunohistochemical histoscores based on the intensity and extent of staining were calculated. RESULTS: Forty cases were gestational and 10 were nongestational ASR. In 19 (38%), the reaction was extensive and involved >50% of the glands. A stromal decidual change was found in 31 (77.5%) of the gestational and 3 (30%) of the nongestational cases. Napsin A was positive in all gestational and 8 of 10 (80%) nongestational ASR. All ASR showed HNF-1ß expression. ER expression was reduced in 37 (92.5%) and lost in 3 (7.5%) gestational ASR, and reduced in 9 (90%) and lost in 1 (10%) of nongestational ASR. None of the ASR in our series expressed PR. CONCLUSIONS: Naspin A and HNF-1ß were frequently expressed in both gestational and nongestational ASR, and ER expression was usually either reduced or loss. Interpretation of these markers in small biopsies containing atypical clear cells should be made with caution.
Subject(s)
Adenocarcinoma, Clear Cell/diagnosis , Biomarkers, Tumor/analysis , Endometrial Neoplasms/diagnosis , Uterine Diseases/diagnosis , Adolescent , Adult , Aspartic Acid Endopeptidases/analysis , Aspartic Acid Endopeptidases/biosynthesis , Diagnosis, Differential , Female , Hepatocyte Nuclear Factor 1-beta/analysis , Hepatocyte Nuclear Factor 1-beta/biosynthesis , Humans , Pregnancy , Receptors, Estrogen/analysis , Receptors, Estrogen/biosynthesis , Receptors, Progesterone/analysis , Receptors, Progesterone/biosynthesis , Young AdultABSTRACT
Alzheimer's disease (AD) is a leading cause of dementia. However, the mechanisms responsible for development of AD, especially for the sporadic variant, are still not clear. In our previous study, we discovered that a small noncoding RNA (miR-188-3p) targeting ß-site amyloid precursor protein cleaving enzyme (BACE)-1, a key enzyme responsible for Aß formation, plays an important role in the development of neuropathology in AD. In the present study, we identified that miR-338-5p, a new miRNA that also targets BACE1, contributes to AD neuropathology. We observed that expression of miR-338-5p was significantly down-regulated in the hippocampus of patients with AD and 5XFAD transgenic (TG) mice, an animal model of AD. Overexpression of miR-338-5p in the hippocampus of TG mice reduced BACE1 expression, Aß formation, and neuroinflammation. Overexpression of miR-338-5p functionally prevented impairments in long-term synaptic plasticity, learning ability, and memory retention in TG mice. In addition, we provide evidence that down-regulated expression of miR-338-5p in AD is regulated through the NF-κB signaling pathway. Our results suggest that down-regulated expression of miR-338-5p plays an important role in the development of AD.-Qian, Q., Zhang, J., He, F.-P., Bao, W.-X., Zheng, T.-T., Zhou, D.-M., Pan, H.-Y., Zhang, H., Zhang, X.-Q., He, X., Sun, B.-G., Luo, B.-Y., Chen, C., Peng, G.-P. Down-regulated expression of microRNA-338-5p contributes to neuropathology in Alzheimer's disease.
Subject(s)
Alzheimer Disease/genetics , Hippocampus/metabolism , MicroRNAs/physiology , 3' Untranslated Regions , Alzheimer Disease/metabolism , Amyloid Precursor Protein Secretases/biosynthesis , Amyloid Precursor Protein Secretases/genetics , Amyloid beta-Peptides/metabolism , Animals , Aspartic Acid Endopeptidases/biosynthesis , Aspartic Acid Endopeptidases/genetics , Cells, Cultured , Disease Models, Animal , Down-Regulation , Humans , Inflammation , Male , Maze Learning , Memory Disorders/genetics , Memory Disorders/prevention & control , Mice , Mice, Transgenic , MicroRNAs/biosynthesis , MicroRNAs/genetics , NF-kappa B/physiology , Neuronal Plasticity , Neurons/metabolism , Peptide Fragments/metabolism , Primary Cell Culture , Recombinant Proteins/metabolismABSTRACT
A recent study has shown that early growth response 1 (EGR1) plays a critical role in the ß-amyloid cascade and tau hypotheses. In addition, evidence has suggested that EGR1 can regulate levels of amyloid-beta peptides, key molecules in the pathogenesis of Alzheimer's disease (AD). However, whether EGR1 is a deleterious or protective factor in the AD is still controversial. In this present study, we constructed an overexpression plasmid, CMV-EGFP-EGR1-Kanamycin, and transfected it into U87MG cells to investigate the effects of EGR1 expression on amyloid-ß (1-40) peptide (Aß40) levels. U87MG cells transfected by CMV-EGFP-EGR1-Kanamycin and CMV-EGFP-Kanamycin were assigned, respectively, to experimental and control groups. Fluorescence microscopy was used to observe transfection efficiencies of the plasmids after 6 hours. EGR1 messenger RNA levels were measured by quantitative reverse transcription polymerase chain reaction. Aß40 secretion was analyzed by enzyme-linked immunosorbent assay. Expression of the amyloid precursor protein, beta-secretase enzyme, and presenilin 1 proteins were analyzed by Western blot analysis. The results showed that EGR1 overexpression increased Aß40 secretion in vitro, possibly through increasing BACE1 expression. Based on these results, EGR1 might be a promising therapeutic target for the AD.
Subject(s)
Amyloid Precursor Protein Secretases/biosynthesis , Amyloid beta-Peptides/metabolism , Aspartic Acid Endopeptidases/biosynthesis , Early Growth Response Protein 1/biosynthesis , Gene Expression Regulation, Enzymologic , Peptide Fragments/metabolism , Amyloid Precursor Protein Secretases/genetics , Amyloid beta-Peptides/genetics , Aspartic Acid Endopeptidases/genetics , Cell Line, Tumor , Early Growth Response Protein 1/genetics , Humans , Peptide Fragments/genetics , RNA, Messenger/biosynthesis , RNA, Messenger/geneticsABSTRACT
Numerous studies have focused on the deteriorate role of amyloid-ß (Aß) on retina, implying the potential pathogenic mechanism underlying age-related macular degeneration (AMD). However, the mechanism underlying the Aß deposition in AMD patients remains unknown. Beta-site amyloid precursor protein-cleaving enzyme 1 (BACE1), rate-limiting enzyme for Aß production, plays an important role in Aß deposition in the brain. In the current study, we aimed to clarify the regulation mechanism of BACE1 and explore potential drug targets using a lipofuscinfluorophore A2E-mediated photo-oxidation model. In this model, Aß1-40 and Aß1-42 levels increased simultaneously with the enhanced BACE1 expression. These changes were associated with the hypomethylation of specific loci within the BACE1 gene promoter and the decreased levels of DNA methyltransferase 1 (DNMT1). Furthermore, we noticed overlapping regions of differentially methylated CpG islands and specificity protein (Sp1) binding sites within the BACE1 promoter. We employed chromatin immunoprecipitation (ChIP) assay to verify that the decreased BACE1 promoter methylation by DNMT1 enabled increased binding between Sp1 and the BACE1 promoter, which further enhanced BACE1 transcription. The inhibition of Sp1 with mithramycin A (MTM) could down-regulate the expression of BACE1 as well as alleviate the RPE barrier morphology and function impairment. Our results for the first time show the competitive regulation of BACE1 by transcription factor Sp1 and DNMT1 after photo-oxidation and confirm the potential novel protective role of MTM on RPE cells.
Subject(s)
Amyloid Precursor Protein Secretases/biosynthesis , Aspartic Acid Endopeptidases/biosynthesis , DNA (Cytosine-5-)-Methyltransferase 1/metabolism , Photic Stimulation/adverse effects , Retinal Pigment Epithelium/metabolism , Retinoids/toxicity , Sp1 Transcription Factor/metabolism , Amyloid Precursor Protein Secretases/antagonists & inhibitors , Amyloid Precursor Protein Secretases/genetics , Amyloid beta-Peptides/metabolism , Aspartic Acid Endopeptidases/antagonists & inhibitors , Aspartic Acid Endopeptidases/genetics , Base Sequence , Cell Line , Dose-Response Relationship, Drug , Gene Expression , Humans , Oxidative Stress/drug effects , Oxidative Stress/physiology , Plicamycin/analogs & derivatives , Plicamycin/pharmacology , Protein Binding/drug effects , Protein Binding/physiology , Retinal Pigment Epithelium/drug effects , Retinal Pigment Epithelium/pathology , Retinal Pigments/toxicityABSTRACT
The goal of this study was to isolate cancer stem-like cells marked by high expression of CD44, a putative cancer stem cell marker, from primary oral squamous cell carcinomas and identify distinctive gene expression patterns in these cells. From 1 October 2013 to 4 September 2015, 76 stage III-IV primary oral squamous cell carcinoma of the gingivobuccal sulcus were resected. In all, 13 tumours were analysed by immunohistochemistry to visualise CD44-expressing cells. Expression of CD44 within The Cancer Genome Atlas-Head and Neck Squamous Cell Carcinoma RNA-sequencing data was also assessed. Seventy resected tumours were dissociated into single cells and stained with antibodies to CD44 as well as CD45 and CD31 (together referred as Lineage/Lin). From 45 of these, CD44+Lin- and CD44-Lin- subpopulations were successfully isolated using fluorescence-activated cell sorting, and good-quality RNA was obtained from 14 such sorted pairs. Libraries from five pairs were sequenced and the results analysed using bioinformatics tools. Reverse transcription quantitative polymerase chain reaction was performed to experimentally validate the differential expression of selected candidate genes identified from the transcriptome sequencing in the same 5 and an additional 9 tumours. CD44 was expressed on the surface of poorly differentiated tumour cells, and within the The Cancer Genome Atlas-Head and Neck Squamous Cell Carcinoma samples, its messenger RNA levels were higher in tumours compared to normal. Transcriptomics revealed that 102 genes were upregulated and 85 genes were downregulated in CD44+Lin- compared to CD44-Lin- cells in at least 3 of the 5 tumours sequenced. The upregulated genes included those involved in immune regulation, while the downregulated genes were enriched for genes involved in cell adhesion. Decreased expression of PCDH18, MGP, SPARCL1 and KRTDAP was confirmed by reverse transcription quantitative polymerase chain reaction. Lower expression of the cell-cell adhesion molecule PCDH18 correlated with poorer overall survival in the The Cancer Genome Atlas-Head and Neck Squamous Cell Carcinoma data highlighting it as a potential negative prognostic factor in this cancer.
Subject(s)
Cadherins/biosynthesis , Carcinoma, Squamous Cell/genetics , Cell Adhesion/genetics , Hyaluronan Receptors/genetics , Mouth Neoplasms/genetics , Neoplastic Stem Cells/pathology , Aspartic Acid Endopeptidases/biosynthesis , Biomarkers, Tumor/immunology , Calcium-Binding Proteins/biosynthesis , Carcinoma, Squamous Cell/pathology , Cell Line, Tumor , Extracellular Matrix Proteins/biosynthesis , Flow Cytometry , Gene Expression Regulation, Neoplastic/genetics , Human papillomavirus 16/genetics , Human papillomavirus 16/isolation & purification , Human papillomavirus 18/genetics , Human papillomavirus 18/isolation & purification , Humans , Hyaluronan Receptors/immunology , Hyaluronan Receptors/metabolism , Leukocyte Common Antigens/immunology , Mouth Neoplasms/pathology , Platelet Endothelial Cell Adhesion Molecule-1/immunology , Protocadherins , RNA, Messenger/genetics , Reverse Transcriptase Polymerase Chain Reaction , Matrix Gla ProteinABSTRACT
Candida species are opportunistic fungal pathogens, which are known for their biofilm associated infections on implanted medical devices in clinical settings. Broad spectrum usage of azole groups and other antifungal agents leads to the occurrence of drug resistance among Candida species. Most of the antifungal agents have failed to treat the biofilm mediated Candida infections. In the present study, silver nanoparticles (AgNPs) were synthesized using Dodonaea viscosa and Hyptis suoveolens methanolic leaf extracts and characterized by ultraviolet-visible absorption spectroscopy, X-ray diffraction analysis, Fourier transform infrared spectroscopy and Scanning electron microscopy, Dynamic light scattering, and Zeta potential analysis. The main goal of this study was to assess the AgNPs for their antibiofilm efficacy against Candida spp. through microscopic analysis and in vitro virulence assays. The results revealed that AgNPs strongly inhibited more than 80% biofilm formed by Candida spp. Furthermore, the AgNPs also reduced the yeast-to-hyphal transition, exopolysaccharide biosynthesis, secreted aspartyl proteinase production which are the major virulence factors of Candida species. This study reveals that biosynthesized AgNPs can be considered for the treatment of biofilm related Candida infections.
Subject(s)
Antifungal Agents/pharmacology , Biofilms/drug effects , Candida/drug effects , Green Chemistry Technology , Metal Nanoparticles/chemistry , Plant Extracts/chemistry , Silver/chemistry , Antifungal Agents/chemistry , Aspartic Acid Endopeptidases/biosynthesis , Biofilms/growth & development , Fungal Polysaccharides/biosynthesis , Hyphae/growth & development , Lamiaceae , Metal Nanoparticles/ultrastructure , Microbial Sensitivity Tests , Microscopy, Electron , Sapindaceae , Silver/pharmacology , Spectroscopy, Fourier Transform Infrared , Virulence Factors/biosynthesisABSTRACT
Pulmonary large cell neuroendocrine carcinoma (LCNEC) is a highly aggressive malignancy, which was recently found to comprise three major genomic subsets: small cell carcinoma-like, non-small cell carcinoma (predominantly adenocarcinoma)-like, and carcinoid-like. To further characterize adenocarcinoma-like subset, here we analyzed the expression of exocrine marker napsin A, along with TTF-1, in a large series of LCNECs (n=112), and performed detailed clinicopathologic and genomic analysis of napsin A-positive cases. For comparison, we analyzed napsin A expression in other lung neuroendocrine neoplasms (177 carcinoids, 37 small cell carcinomas) and 60 lung adenocarcinomas. We found that napsin A was expressed in 15% of LCNEC (17/112), whereas all carcinoids and small cell carcinomas were consistently negative. Napsin A reactivity in LCNEC was focal in 12/17 cases, and weak or moderate in intensity in all cases, which was significantly lower in the extent and intensity than seen in adenocarcinomas (P<0.0001). The combination of TTF-1-diffuse/napsin A-negative or focal was typical of LCNEC but was rare in adenocarcinoma, and could thus serve as a helpful diagnostic clue. The diagnosis of napsin A-positive LCNECs was confirmed by classic morphology, diffuse labeling for at least one neuroendocrine marker, most consistently synaptophysin, and the lack of distinct adenocarcinoma component. Genomic analysis of 14 napsin A-positive LCNECs revealed the presence of mutations typical of lung adenocarcinoma (KRAS and/or STK11) in 11 cases. In conclusion, LCNECs are unique among lung neuroendocrine neoplasms in that some of these tumors exhibit low-level expression of exocrine marker napsin A, and harbor genomic alterations typical of adenocarcinoma. Despite the apparent close biological relationship, designation of adeno-like LCNEC as a separate entity from adenocarcinoma is supported by their distinctive morphology, typically diffuse expression of neuroendocrine marker(s) and aggressive behavior. Further studies are warranted to assess the clinical utility and optimal method of identifying adenocarcinoma-like and other subsets of LCNEC in routine practice.