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1.
Am J Hum Genet ; 108(3): 411-430, 2021 03 04.
Article in English | MEDLINE | ID: mdl-33626337

ABSTRACT

Genetic factors underlying coronary artery disease (CAD) have been widely studied using genome-wide association studies (GWASs). However, the functional understanding of the CAD loci has been limited by the fact that a majority of GWAS variants are located within non-coding regions with no functional role. High cholesterol and dysregulation of the liver metabolism such as non-alcoholic fatty liver disease confer an increased risk of CAD. Here, we studied the function of non-coding single-nucleotide polymorphisms in CAD GWAS loci located within liver-specific enhancer elements by identifying their potential target genes using liver cis-eQTL analysis and promoter Capture Hi-C in HepG2 cells. Altogether, 734 target genes were identified of which 121 exhibited correlations to liver-related traits. To identify potentially causal regulatory SNPs, the allele-specific enhancer activity was analyzed by (1) sequence-based computational predictions, (2) quantification of allele-specific transcription factor binding, and (3) STARR-seq massively parallel reporter assay. Altogether, our analysis identified 1,277 unique SNPs that display allele-specific regulatory activity. Among these, susceptibility enhancers near important cholesterol homeostasis genes (APOB, APOC1, APOE, and LIPA) were identified, suggesting that altered gene regulatory activity could represent another way by which genetic variation regulates serum lipoprotein levels. Using CRISPR-based perturbation, we demonstrate how the deletion/activation of a single enhancer leads to changes in the expression of many target genes located in a shared chromatin interaction domain. Our integrative genomics approach represents a comprehensive effort in identifying putative causal regulatory regions and target genes that could predispose to clinical manifestation of CAD by affecting liver function.


Subject(s)
Coronary Artery Disease/genetics , Enhancer Elements, Genetic/genetics , Genetic Predisposition to Disease , Quantitative Trait Loci/genetics , Alleles , Chromatin/genetics , Coronary Artery Disease/pathology , Female , Genome-Wide Association Study/methods , Genomics , Humans , Liver/metabolism , Male , Molecular Sequence Annotation , Organ Specificity/genetics , Polymorphism, Single Nucleotide/genetics , Promoter Regions, Genetic/genetics , Protein Binding/genetics , Risk Factors
2.
Arterioscler Thromb Vasc Biol ; 40(11): 2665-2677, 2020 11.
Article in English | MEDLINE | ID: mdl-32938217

ABSTRACT

OBJECTIVE: Previous studies have demonstrated that the expression of several lysine (K)-specific demethylases (KDMs) is induced by hypoxia. Here, we sought to investigate the exact mechanisms underlying this regulation and its functional implications for endothelial cell function, such as angiogenesis. Approach and Results: We analyzed the expression changes of KDMs under hypoxia and modulation of HIF (hypoxia-inducible factor) expression using GRO-Seq and RNA-Seq in endothelial cells. We provide evidence that the majority of the KDMs are induced at the level of nascent transcription mediated by the action of HIF-1α and HIF-2α. Importantly, we show that transcriptional changes at the level of initiation represent the major mechanism of gene activation. To delineate the epigenetic effects of hypoxia and HIF activation in normoxia, we analyzed the genome-wide changes of H3K27me3 using chromosome immunoprecipitation-Seq. We discovered a redistribution of H3K27me3 at ≈2000 to 3000 transcriptionally active loci nearby genes implicated in angiogenesis. Among these, we demonstrate that vascular endothelial growth factor A (VEGFA) expression is partly induced by KDM4B- and KDM6B-mediated demethylation of nearby regions. Knockdown of KDM4B and KDM6B decreased cell proliferation, tube formation, and endothelial sprouting while affecting hundreds of genes associated with angiogenesis. These findings provide novel insights into the regulation of KDMs by hypoxia and the epigenetic regulation of VEGFA-mediated angiogenesis. CONCLUSIONS: Our study describes an additional level of epigenetic regulation where hypoxia induces redistribution of H3K27me3 around genes implicated in proliferation and angiogenesis. More specifically, we demonstrate that KDM4B and KDM6B play a key role in modulating the expression of the major angiogenic driver VEGFA.


Subject(s)
Histone Demethylases/metabolism , Histones/metabolism , Human Umbilical Vein Endothelial Cells/enzymology , Neovascularization, Physiologic , Basic Helix-Loop-Helix Transcription Factors/genetics , Basic Helix-Loop-Helix Transcription Factors/metabolism , Cell Hypoxia , Cells, Cultured , Demethylation , Histone Demethylases/genetics , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Jumonji Domain-Containing Histone Demethylases/genetics , Jumonji Domain-Containing Histone Demethylases/metabolism , Protein Processing, Post-Translational , Signal Transduction , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolism
3.
AAPS PharmSciTech ; 19(2): 668-680, 2018 Feb.
Article in English | MEDLINE | ID: mdl-28948584

ABSTRACT

The current International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) methods for determining the supported shelf life of a drug product, described in ICH guidance documents Q1A and Q1E, are evaluated in this paper. To support this evaluation, an industry data set is used which is comprised of 26 individual stability batches of a common drug product where most batches are measured over a 24 month storage period. Using randomly sampled sets of 3 or 6 batches from the industry data set, the current ICH methods are assessed from three perspectives. First, the distributional properties of the supported shelf lives are summarized and compared to the distributional properties of the true shelf lives associated with the industry data set, assuming the industry data set represents a finite population of drug product batches for discussion purposes. Second, the results of the ICH "poolability" tests for model selection are summarized and the separate shelf life distributions from the possible alternative models are compared. Finally, the ICH methods are evaluated in terms of their ability to manage risk. Shelf life estimates that are too long result in an unacceptable percentage of nonconforming batches at expiry while those that are too short put the manufacturer at risk of possibly having to prematurely discard safe and efficacious drug product. Based on the analysis of the industry data set, the ICH-recommended approach did not produce supported shelf lives that effectively managed risk. Alternative approaches are required.


Subject(s)
Drug Industry/standards , Drug Stability , Drug Storage/standards , Drug Storage/methods , Humans , Research Design , Risk Management , United States , United States Food and Drug Administration/standards
4.
Infect Immun ; 85(10)2017 10.
Article in English | MEDLINE | ID: mdl-28694295

ABSTRACT

Emerging evidence shows that the human microbiota plays a larger role in disease progression and health than previously anticipated. Helicobacter pylori, the causative agent of gastric cancer and duodenal and gastric ulcers, was early associated with gastric disease, but it has also been proposed that the accompanying microbiota in Helicobacter pylori-infected individuals might affect disease progression and gastric cancer development. In this study, the composition of the transcriptionally active microbial community and H. pylori gene expression were determined using metatranscriptomic RNA sequencing of stomach biopsy specimens from individuals with different H. pylori infection statuses and premalignant tissue changes. The results show that H. pylori completely dominates the microbiota not only in infected individuals but also in most individuals classified as H. pylori uninfected using conventional methods. Furthermore, H. pylori abundance is positively correlated with the presence of Campylobacter, Deinococcus, and Sulfurospirillum Finally, we quantified the expression of a large number of Helicobacter pylori genes and found high expression of genes involved in pH regulation and nickel transport. Our study is the first to dissect the viable microbiota of the human stomach by metatranscriptomic analysis, and it shows that metatranscriptomic analysis of the gastric microbiota is feasible and can provide new insights into how bacteria respond in vivo to variations in the stomach microenvironment and at different stages of disease progression.


Subject(s)
Carcinogenesis , Gastrointestinal Microbiome , Helicobacter Infections/microbiology , Helicobacter pylori/genetics , Stomach Neoplasms/microbiology , Stomach/microbiology , Transcriptome , Adult , Aged , Bacteria/genetics , Bacteria/isolation & purification , Disease Progression , Female , Gastric Mucosa/microbiology , Gastritis, Atrophic/microbiology , Gastritis, Atrophic/pathology , Gene Expression Profiling , Helicobacter Infections/pathology , Humans , Male , Microbial Viability , Middle Aged , Stomach/pathology , Young Adult
5.
Circ Cardiovasc Genet ; 10(3)2017 Jun.
Article in English | MEDLINE | ID: mdl-28611032

ABSTRACT

BACKGROUND: Microarrays and RNA sequencing are widely used to profile transcriptome remodeling during myocardial ischemia. However, the steady-state RNA analysis lacks in sensitivity to detect all noncoding RNA species and does not provide separation between transcriptional and post-transcriptional regulations. Here, we provide the first comprehensive analysis of nascent RNA profiles of mRNAs, primary micro-RNAs, long noncoding RNAs, and enhancer RNAs in a large animal model of acute infarction. METHODS AND RESULTS: Acute infarction was induced by cardiac catheterization of domestic swine. Nuclei isolated from healthy, border zone, and ischemic regions of the affected heart were subjected to global run-on sequencing. Global run-on sequencing analysis indicated that half of affected genes are regulated at the level of transcriptional pausing. A gradient of induction of inflammatory mediators and repression of peroxisome proliferator-activated receptor signaling and oxidative phosphorylation was detected when moving from healthy toward infarcted area. In addition, we interrogated the transcriptional regulation of primary micro-RNAs and provide evidence that several arrhythmia-related target genes exhibit repression at post-transcriptional level. We identified 450 long noncoding RNAs differently regulated by ischemia, including novel conserved long noncoding RNAs expressed in antisense orientation to myocardial transcription factors GATA-binding protein 4, GATA-binding protein 6, and Krüppel-like factor 6. Finally, characterization of enhancers exhibiting differential expression of enhancer RNAs pointed a central role for Krüppel-like factor, MEF2C, ETS, NFY, ATF, E2F2, and NRF1 transcription factors in determining transcriptional responses to ischemia. CONCLUSIONS: Global run-on sequencing allowed us to follow the gradient of gene expression occurring in the ischemic heart and identify novel noncoding RNAs regulated by oxygen deprivation. These findings highlight potential new targets for diagnosis and treatment of myocardial ischemia.


Subject(s)
Myocardial Infarction/pathology , Myocardium/metabolism , RNA, Untranslated/metabolism , Animals , Cells, Cultured , GATA4 Transcription Factor/genetics , GATA6 Transcription Factor/genetics , Gene Expression Regulation , Gene Regulatory Networks , Genome , Kruppel-Like Factor 6/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , Myocardial Infarction/genetics , Myocytes, Cardiac/cytology , Myocytes, Cardiac/metabolism , Nuclear Respiratory Factor 1/genetics , Peroxisome Proliferator-Activated Receptors/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , RNA, Messenger/metabolism , RNA, Untranslated/genetics , Signal Transduction/genetics , Swine
6.
J Pharm Anal ; 6(1): 11-17, 2016 Feb.
Article in English | MEDLINE | ID: mdl-29403957

ABSTRACT

A novel method for simultaneous determination of kolliphor HS15 and miglyol 812 in microemulsion formulation was developed using ultra-high performance liquid chromatography coupled with a nano quantitation analytical detector (UHPLC-NQAD). All components in kolliphor HS15 and miglyol 812 were well separated on an Acquity BEH C18 column. Mobile phase A was 0.1% trifluoroacetic acid (TFA) in water and mobile phase B was acetonitrile. A gradient elution sequence was programed initially with 60% organic solvent, slowly increased to 100% within 8 min. The flow rate was 0.7 mL/min. Good linearity (r>0.95) was obtained in the range of 27.6-1381.1 µg/mL for polyoxyl 15 hydroxystearate in kolliphor HS15, 0.8-202.0 µg/mL for caprylic acid triglyceride and 2.7-221.9 µg/mL for capric acid triglyceride in miglyol 812. The relative standard deviations (RSD) ranged from 0.6% to 1.7% for intra-day precision and from 0.4% to 2.7% for inter-day precision. The overall recoveries (accuracy) were 99.7%-101.4% for polyoxyl 15 hydroxystearate in kolliphor HS15, 96.7%-99.6% for caprylic acid triglyceride, and 94.1%-103.3% for capric acid triglyceride in miglyol 812. Quantification limits (QL) were determined as 27.6 µg/mL for polyoxyl 15 hydroxystearate in kolliphor HS15, 0.8 µg/mL for caprylic acid triglyceride, and 2.7 µg/mL for capric acid triglyceride in miglyol 812. No interferences were observed in the retention time ranges of kolliphor HS15 and miglyol 812. The method was validated in terms of specificity, linearity, precision, accuracy, QL, and robustness. The proposed method has been applied to microemulsion formulation analyses with good recoveries (82.2%-103.4%).

7.
Appl Spectrosc ; 69(9): 219A-20A, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26414519
8.
J Pharm Anal ; 5(4): 223-230, 2015 Aug.
Article in English | MEDLINE | ID: mdl-29403935

ABSTRACT

Oleic acid is a common pharmaceutical excipient that has been widely used in various dosage forms. Gas chromatography (GC) has often been used as the quantitation method for fatty acids normally requiring a derivatization step. The aim of this study was to develop a simple, robust, and derivatization-free GC method that is suitable for routine analysis of all the major components in oleic acid USP-NF (United States Pharmacopeia-National Formulary) material. A gas chromatography-flame ionization detection (GC-FID) method was developed for direct quantitative analysis of oleic acid and related fatty acids in oleic acid USP-NF material. Fifteen fatty acids were separated using a DB-FFAP (nitroterephthalic acid modified polyethylene glycol) capillary GC column (30 m×0.32 mm i.d.) with a total run time of 20 min. The method was validated in terms of specificity, linearity, precision, accuracy, sensitivity, and robustness. The method can be routinely used for the purpose of oleic acid USP-NF material analysis.

9.
Ther Deliv ; 5(3): 297-317, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24592955

ABSTRACT

Over the past decade, orally inhaled fixed-dose combination products (FDCs) have emerged as an important therapeutic class for the treatment of asthma and chronic obstructive pulmonary disease. However, the conceptual simplicity of inhaled FDCs belies both the complexity of their development, and the profound advantages they offer patients. The benefits of combining agents are not merely additive, and range from increased compliance via simple convenience to complex receptor-level synergies. Similarly, though, the development challenges often exceed the sum of their parts. FDC formulation and analytical method development is generally more complex than for two monotherapy products. Likewise, FDC clinical programs can easily eclipse those of their monotherapy peers and their inherent complexity is often furthered by the diverse regulatory requirements for worldwide approval. As such, the proposition of developing an orally inhaled FDC for global registration often represents a significant increase in both the potential rewards and assumed risks of drug development.


Subject(s)
Anti-Asthmatic Agents/administration & dosage , Asthma/drug therapy , Bronchodilator Agents/administration & dosage , Drug Dosage Calculations , Pulmonary Disease, Chronic Obstructive/drug therapy , Administration, Inhalation , Aerosols , Anti-Asthmatic Agents/standards , Bronchodilator Agents/standards , Chemistry, Pharmaceutical , Drug Approval , Drug Combinations , Humans , Nebulizers and Vaporizers , Particle Size , Quality Control , Technology, Pharmaceutical/methods
10.
AAPS PharmSciTech ; 13(3): 911-8, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22729779

ABSTRACT

This article proposes new terminology that distinguishes between different concepts involved in the discussion of the shelf life of pharmaceutical products. Such comprehensive and common language is currently lacking from various guidelines, which confuses implementation and impedes comparisons of different methodologies. The five new terms that are necessary for a coherent discussion of shelf life are: true shelf life, estimated shelf life, supported shelf life, maximum shelf life, and labeled shelf life. These concepts are already in use, but not named as such. The article discusses various levels of "product" on which different stakeholders tend to focus (e.g., a single-dosage unit, a batch, a production process, etc.). The article also highlights a key missing element in the discussion of shelf life-a Quality Statement, which defines the quality standard for all key stakeholders. Arguments are presented that for regulatory and statistical reasons the true product shelf life should be defined in terms of a suitably small quantile (e.g., fifth) of the distribution of batch shelf lives. The choice of quantile translates to an upper bound on the probability that a randomly selected batch will be nonconforming when tested at the storage time defined by the labeled shelf life. For this strategy, a random-batch model is required. This approach, unlike a fixed-batch model, allows estimation of both within- and between-batch variability, and allows inferences to be made about the entire production process. This work was conducted by the Stability Shelf Life Working Group of the Product Quality Research Institute.


Subject(s)
Drug Stability , Drug Storage/standards , Pharmaceutical Preparations/standards , Time Factors
11.
J Chromatogr A ; 1218(16): 2311-9, 2011 Apr 22.
Article in English | MEDLINE | ID: mdl-21376330

ABSTRACT

While supercritical fluid chromatography (SFC) has received great popularity in chiral separation and purification, it has rarely been used for trace level pharmaceutical impurity analysis, partially due to the limitation of instrument sensitivity. In this study, a packed column SFC method has been developed for the quantitative analysis of mometasone furoate and its trace level impurities. The UV detection was optimized to improve the sensitivity by 2-4 fold. In combination with an increased sample concentration, this SFC method is capable of trace level (0.05% of the active) analysis of the impurities. The SFC method used a silica column and a mobile phase consisting of CO(2) and methanol. The new method provides an orthogonal selectivity complementary to the reversed phase HPLC (RP-HPLC) method. All of the impurities and the active were baseline separated within 12 min on SFC, which is less than one third of the RP-HPLC method run time. The method was also partially validated for linearity, accuracy, precision (repeatability), and limit of quantitation. This study demonstrated that the SFC method, with improved sensitivity, can be a valuable tool to provide orthogonal selectivity for trace level impurity separation. With further validation, the method may be suitable for release testing and stability testing for mometasone furoate drug substance.


Subject(s)
Chromatography, Supercritical Fluid/methods , Drug Contamination , Pregnadienediols/analysis , Carbon Dioxide , Chromatography, Supercritical Fluid/standards , Methanol , Mometasone Furoate , Regression Analysis , Reproducibility of Results , Sensitivity and Specificity
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