scholarly journals Genetic regulation of expression of leukotriene A4 hydrolase

2016 ◽  
Vol 2 (1) ◽  
pp. 00058-2015 ◽  
Author(s):  
Tomasz Szul ◽  
Peter Castaldi ◽  
Michael H. Cho ◽  
J. Edwin Blalock ◽  
Amit Gaggar
Keyword(s):  
Promoter Region ◽  
Inflammatory Responses ◽  
Luciferase Reporter ◽  
Aminopeptidase Activity ◽  
Chronic Obstructive ◽  
Luciferase Reporter Gene ◽  
Putative Promoter ◽  
Leukotriene A4 Hydrolase ◽  
Leukotriene A4 ◽  
The Impact

In chronic inflammatory lung disorders such as chronic obstructive pulmonary disease (COPD), the concurrent organ-specific and systemic inflammatory responses lead to airway remodelling and vascular dysfunction. Although a major common risk factor for COPD, cigarette smoke alone cannot explain the progression of this disease; there is increasing evidence that genetic predisposition also plays a role in COPD susceptibility and progression. A key enzyme in chronic lung inflammation is leukotriene A4 hydrolase (LTA4H). With its aminopeptidase activity, LTA4H degrades the neutrophil chemoattractant tripeptide PGP.In this study, we used the luciferase reporter gene analysis system and quantitative trait locus analysis to explore the impact of single-nucleotide polymorphisms (SNPs) in the putative promoter region ofLTA4Hon LTA4H expression.We show that not only is the putative promoter ofLTA4Hlarger than previously reported but also that SNPs in the expanded promoter region regulate expression of LTA4H both in cell-based systems and in peripheral blood samples from human subjects.These findings provide significant evidence for an active region upstream of the previously reportedLTA4Hpromoter, which may have implications related to ongoing inflammatory processes in chronic lung disease.

scholarly journals Functional Properties and Molecular Architecture of Leukotriene A4 Hydrolase, a Pivotal Catalyst of Chemotactic Leukotriene Formation

2002 ◽  
Vol 2 ◽  
pp. 1734-1749 ◽  
Author(s):  
Jesper Z. Haeggström ◽  
Pär Nordlund ◽  
Marjolein M.G.M. Thunnissen
Keyword(s):  
Inflammatory Diseases ◽  
Biological Effects ◽  
Leukotriene B4 ◽  
Aminopeptidase Activity ◽  
Chronic Obstructive ◽  
Molecular Architecture ◽  
Obstructive Pulmonary Disease ◽  
Recent Developments ◽  
Leukotriene A4 Hydrolase ◽  
Leukotriene A4

The leukotrienes are a family of lipid mediators involved in inflammation and allergy. Leukotriene B4is a classical chemoattractant, which triggers adherence and aggregation of leukocytes to the endothelium at only nM concentrations. In addition, leukotriene B4modulates immune responses, participates in the host defense against infections, and is a key mediator of PAF-induced lethal shock. Because of these powerful biological effects, leukotriene B4 is implicated in a variety of acute and chronic inflammatory diseases, e.g., nephritis, arthritis, dermatitis, and chronic obstructive pulmonary disease. The final step in the biosynthesis of leukotriene B4is catalyzed by leukotriene A4hydrolase, a unique bifunctional zinc metalloenzyme with an anion-dependent aminopeptidase activity. Here we describe the most recent developments regarding our understanding of the function and molecular architecture of leukotriene A4hydrolase.

scholarly journals Impact of RARα and miR-138 on retinoblastoma etoposide resistance

Tumor Biology ◽  
2021 ◽  
Vol 43 (1) ◽  
pp. 11-26
Author(s):  
Maike Busch ◽  
Natalia Miroschnikov ◽  
Jaroslaw Thomas Dankert ◽  
Marc Wiesehöfer ◽  
Klaus Metz ◽  
...  
Keyword(s):  
Cell Viability ◽  
Cell Lines ◽  
Cancer Progression ◽  
Treated Patient ◽  
Luciferase Reporter ◽  
Luciferase Reporter Gene ◽  
Gene Assay ◽  
The Impact

BACKGROUND: Retinoblastoma (RB) is the most common childhood eye cancer. Chemotherapeutic drugs such as etoposide used in RB treatment often cause massive side effects and acquired drug resistances. Dysregulated genes and miRNAs have a large impact on cancer progression and development of chemotherapy resistances. OBJECTIVE: This study was designed to investigate the involvement of retinoic acid receptor alpha (RARα) in RB progression and chemoresistance as well as the impact of miR-138, a potential RARα regulating miRNA. METHODS: RARα and miR-138 expression in etoposide resistant RB cell lines and chemotherapy treated patient tumors compared to non-treated tumors was revealed by Real-Time PCR. Overexpression approaches were performed to analyze the effects of RARα on RB cell viability, apoptosis, proliferation and tumorigenesis. Besides, we addressed the effect of miR-138 overexpression on RB cell chemotherapy resistance. RESULTS: A binding between miR-138 and RARα was shown by dual luciferase reporter gene assay. The study presented revealed that RARα is downregulated in etoposide resistant RB cells, while miR-138 is endogenously upregulated. Opposing RARα and miR-138 expression levels were detectable in chemotherapy pre-treated compared to non-treated RB tumor specimen. Overexpression of RARα increases apoptosis levels and reduces tumor cell growth of aggressive etoposide resistant RB cells in vitro and in vivo. Overexpression of miR-138 in chemo-sensitive RB cell lines partly enhances cell viability after etoposide treatment. CONCLUSIONS: Our findings show that RARα acts as a tumor suppressor in retinoblastoma and is downregulated upon etoposide resistance in RB cells. Thus, RARα may contribute to the development and progression of RB chemo-resistance.

scholarly journals BrpA Is Involved in Regulation of Cell Envelope Stress Responses in Streptococcus mutans

2012 ◽  
Vol 78 (8) ◽  
pp. 2914-2922 ◽  
Author(s):  
J. P. Bitoun ◽  
S. Liao ◽  
X. Yao ◽  
S.-J. Ahn ◽  
R. Isoda ◽  
...  
Keyword(s):  
Streptococcus Mutans ◽  
Stress Responses ◽  
Antimicrobial Agents ◽  
Galleria Mellonella ◽  
Cell Envelope ◽  
Luciferase Reporter ◽  
Luciferase Reporter Gene ◽  
Content Type ◽  
Lipid Ii ◽  
The Impact

ABSTRACTPrevious studies have shown that BrpA plays a major role in acid and oxidative stress tolerance and biofilm formation byStreptococcus mutans. Mutant strains lacking BrpA also display increased autolysis and decreased viability, suggesting a role for BrpA in cell envelope integrity. In this study, we examined the impact of BrpA deficiency on cell envelope stresses induced by envelope-active antimicrobials. Compared to the wild-type strain UA159, the BrpA-deficient mutant (TW14D) was significantly more susceptible to antimicrobial agents, especially lipid II inhibitors. Several genes involved in peptidoglycan synthesis were identified by DNA microarray analysis as downregulated in TW14D. Luciferase reporter gene fusion assays also revealed that expression ofbrpAis regulated in response to environmental conditions and stresses induced by exposure to subinhibitory concentrations of cell envelope antimicrobials. In aGalleria mellonella(wax worm) model, BrpA deficiency was shown to diminish the virulence ofS. mutansOMZ175, which, unlikeS. mutansUA159, efficiently kills the worms. Collectively, these results suggest that BrpA plays a role in the regulation of cell envelope integrity and that deficiency of BrpA adversely affects the fitness and diminishes the virulence of OMZ175, a highly invasive strain ofS. mutans.

scholarly journals MiR-92a-3p promote s invasion and migration of hepatocellular carcinoma cells by targeting PTEN

2021 ◽  
Author(s):  
Yilin Hu ◽  
Huiling Sun ◽  
Qiping Lu ◽  
Hongliang Mei ◽  
Rong Liu
Keyword(s):  
Hepatocellular Carcinoma ◽  
Mutation Frequency ◽  
Biological Information ◽  
Luciferase Reporter ◽  
Migration And Invasion ◽  
Clinical Samples ◽  
Luciferase Reporter Gene ◽  
Invasion And Migration ◽  
And Migration ◽  
The Impact

Abstract Background MiR-92a-3p has been reported to play a part in hepatocellular carcinoma (HCC), a leading type of lethal cancer around the world. In this study, we explored the function and mechanism of miR-92a-3p in HCC. Methods Firstly, the expression of miR-92a-3p in HCC along with its relationship with PTEN was analyzed through biological information. To investigate the impact of miR-92a-3p on the migration and invasion of HCC cells, we performed scratch wound healing and transwell assays. Next, RT-qPCR, western blot and dual luciferase reporter gene assays were conducted to determine whether PTEN is targeted by miR-92a-3p, which was then verified through rescue assays. Afterwards, in vivo animal experiments were carried out to determine the function of miR-92a-3p in HCC tissues. As an established fact, PETN is an anti-oncogene with frequent mutation inactivation in human cancers. Thus, we used the database to predict the mutation of PETN and its mutation frequency. Finally, CRISPR-cas12a was applied to detect the R130Q mutation on PETN in HCC clinical samples. Results This study found that the migration and invasion of HCC could be suppressed by inhibiting miR-92a-3p, which regulates the proliferation, migration and invasion of HCC through the regulation of PETN. The bioinformatics analysis indicated higher mutation frequency of R130Q/G/L* site on the PETN gene, and greater impact of R130Q site mutation on the progression of HCC. CRISPR-cas12a detected 26 cases of R130Q mutations on PTEN in 40 HCC clinical samples Conclusion Collectively, this study revealed that miR-92a-3p promoted the invasion and migration of HCC by targeting PTEN, and that the stability of PETN also affected the development of HCC, which may enrich and deepen our knowledge on the progression of HCC.

Activation and inhibition of leukotriene A4 hydrolase aminopeptidase activity by diphenyl ether and derivatives

2008 ◽  
Vol 18 (24) ◽  
pp. 6549-6552 ◽  
Author(s):  
Xiaolu Jiang ◽  
Lu Zhou ◽  
Dengguo Wei ◽  
Hu Meng ◽  
Ying Liu ◽  
...  
Keyword(s):  
Diphenyl Ether ◽  
Aminopeptidase Activity ◽  
Leukotriene A4 Hydrolase ◽  
Leukotriene A4

Overexpressed miR-375-Loaded Restrains Development of Cervical Cancer Through Down-Regulation of Frizzled Class Receptor 4 (FZD4) with Liposome Nanoparticle as a Carrier

2021 ◽  
Vol 17 (9) ◽  
pp. 1882-1889
Author(s):  
Suqin Wang ◽  
Lina Xu ◽  
Zhiqiang Zhang ◽  
Ping Wang ◽  
Rong Zhang ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cervical Cancer ◽  
Cell Proliferation ◽  
Protein Expression ◽  
Signaling Pathway ◽  
Luciferase Reporter ◽  
Luciferase Reporter Gene ◽  
Gene Assay ◽  
M Phase ◽  
The Impact

Dysregulation expression of miR-375 is noted to correlate with progression of cervical cancer. This study attempted to investigate the impact of overexpressed miR-375-loaded liposome nanoparticles on proliferation of cervical cancer (CC), to provide an insight on pathogenesis of CC disorder. CC cells were co-cultured with pure liposome nanoparticles (empty vector group), miR-375 agonist-loaded liposome nanoparticles, or transfected with miR-375 antagonist. Besides, some cells were exposed to TGF-β/Smads signaling pathway inhibitor or activator whilst cell proliferation was assessed by MTT assay, and expressions of FZD4 and miR-375 were determined. Western blot analysis was carried out to detect the expression of TGF-β pathway factors (TGF-β, Smad2, Smad7, p-Smad2) and its downstream Smads pathway. The interaction between miR-375 and FZD4 was evaluated by dual-luciferase reporter gene assay. Overexpression of miR-375 induced arrest at the G0/G1 phase of cell cycle and elevation of Smad2 protein expression (P <0.05), with lower expressions of TGF-β, Smad7, p-Smad2, and FZD4, while transfection with miR-375 inhibitor exhibited opposite activity. Presence of miR-375 agonist-loaded liposome nanoparticles induced decreased cell proliferation. There was a targeting relationship between miR-375 and FZD4, and administration with TGF-β/Smads agonist resulted in increased miR-375 and Smad2 expressions, as well as decreased TGF-β, Smad7, p-Smad2, FZD4 protein expression, and the number of S phase and G2/M phase cells (P < 0.05). The signaling inhibitor oppositely suppressed cell proliferation decreasing miR-375 expression. miR-375-loaded liposome nanoparticles activated TGF-β/Smads signaling pathway to restrain cell cycle and suppress cell division, and proliferation through targeting FZD4 in CC. Its molecular mechanism is related to activation of TGF-β/Smads signaling pathway.

scholarly journals Leukotriene A4 Hydrolase and Tri-aminopeptidase Activity as Potential Quantifiable Biomarkers in the Study of Patients With COPD

2012 ◽  
Vol 138 (suppl 2) ◽  
pp. A112-A112
Author(s):  
Christopher Garrett ◽  
J. Michael Wells ◽  
Phillip J. O’Reilly ◽  
Patricia L. Jackson ◽  
J. Edwin Blalock
Keyword(s):  
Aminopeptidase Activity ◽  
Leukotriene A4 Hydrolase ◽  
Leukotriene A4

scholarly journals Circular RNA circANKS1B as the Sponge of miR-152-3p Promotes Prostate Cancer Progression by up-Regulating TGF-α Expression

2020 ◽  
Author(s):  
Liangjun Tao ◽  
Xinyuan Pan ◽  
Jiawei Wang ◽  
Li Zhang ◽  
Lingsong Tao ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Cancer Progression ◽  
Circular Rna ◽  
Luciferase Reporter ◽  
Migration And Invasion ◽  
Prostate Cancer Progression ◽  
Luciferase Reporter Gene ◽  
Gene Assay ◽  
And Function ◽  
The Impact

Abstract Background: Growing studies indicate that circRNAs play critical roles in human diseases, and show great potential as biomarkers and therapeutic targets. This study aims to investigate the expression and function of circANKS1B in prostate cancer (PC).Methods: The expression of circANKS1B and miRNA-152-3p were determined by real-time qRT-PCR. The cell migration and invasion were measured by transwell assay. The interaction between circANKS1B and miR-152-3p was confirmed by dual-luciferase reporter gene assay. Rescue experiments were conducted to demonstrate whether circANKS1B regulated the migration and invasion of PC cells by the circANKS1B-miR-152-3p-TGF-α pathway.Results: The expression of circANKS1B was dramatically up-regulated both in PC cells and tissues. Moreover, high circANKS1B expression was associated with a poor prognosis of PC patients. Dual-luciferase reporter assay indicated that circABKS1B directly bound to miRNA-152-3p. Furthermore, circANKS1B negatively regulated miR-152-3p expression. Knockdown of circANKS1B remarkably suppressed PC cells invasion and TGF-α expression, while the effects of circANKS1B silencing were reversed by miR-152-3p deficiency. In addition, the impact of miR-152-3p silencing on PC cell invasion was also abrogated by TGF-α deficiency. In all, circANKS1B as the sponge of miR-152-3p promotes prostate cancer progression by up-regulating TGF-α expression.Conclusion: Our findings reveal that circANKS1B could be a potential prognostic biomarker and therapeutic target of PC.

scholarly journals Spike protein up-regulates inflammatory axis of both thromboinflammation and leukotriene in severe COVID-19

2020 ◽  
Author(s):  
Xiaopeng Tang ◽  
Mingqian Fang ◽  
Juan Zhang ◽  
Zhiyi Liao ◽  
Ruomei Cheng ◽  
...  
Keyword(s):  
Epoxide Hydrolase ◽  
Leukotriene B4 ◽  
Spike Protein ◽  
Aminopeptidase Activity ◽  
Healthy Control ◽  
Leukotriene A4 Hydrolase ◽  
Inflammatory Drugs ◽  
Anti Inflammatory ◽  
Leukotriene A4

Abstract Hypercytokinemia is a critically fatal factor in COVID-19. However, underlying pathogenic mechanisms are unknown. Here we show that fibrinogen and leukotriene-A4 hydrolase (LTA4H), two of the most potent inflammatory contributors, are elevated by 67.7 and astonishing 227.7% in the plasma of patients infected by SARS-CoV-2 and admitted to intensive care unit in comparison with healthy control, respectively. Conversely, transferrin identified as a fibrinogen immobilizer in our recent work and Spink6 are down-regulated by 40.3 and 25.9%, respectively. Furthermore, we identify Spink6 as the first endogenous inhibitor of LTA4H, a pro-inflammatory enzyme catalyzing final and rating limited step in biosynthesis of leukotriene-B4 that is an extremely inflammatory mediator and a target to design superior anti-inflammatory drugs. Additionally, virus Spike protein is found to evoke LTA4H and fibrinogen expression in vivo. Collectively, these findings identify the imbalance between inflammatory drivers and antagonists, which likely contributes to hypercytokinemia in COVID-19. Spink6 may have superior anti-inflammatory function because it specifically targets epoxide hydrolase of LTA4H to inhibit leukotriene-B4 biosynthesis without effecting LTA4H’s aminopeptidase activity.

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