Decarbonising Commercial Real Estate: The Role of Operational Performance
Oxidative stress 2014
1. Sample & Assay Technologies
Oxidative Stress and ROS Signaling
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3. Sample & Assay Technologies
Oxidative Stress and ROS Signaling
Overview
Oxidants & antioxidant in biological
systems
Antioxidant defense mechanism
Molecular targets of oxidative stress
Detection of oxidative stress
Research Solutions @ QIAGEN
Gene expression
Epigenetics
Functional studies
Application Examples
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4. Sample & Assay Technologies
Oxidative stress and ROS signaling
Oxidative stress: imbalance between reactive oxygen
species (ROS) and antioxidants.
Under normal conditions, cells are able to balance the
production of oxidants and antioxidants. Oxidative stress
occurs when cells are subjected to excess levels of ROS or
as a result of antioxidant depletion.
ROS: chemically reactive molecules containing
oxygen, highly reactive
Under normal conditions, ROS are natural byproducts.
It also can be generated by exogenous sources.
Major sources of ROS: mitochondria, peroxisome,
plasma membrane/cytoplasm.
Role of reactive oxygen species in cell signaling pathways, Biochemical and Biomedical Aspects of Oxidative Modification 2001
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Endogenous
sources
Mitochondria
Peroxisomes
Cytochrome P450
Exogenous sources
UV light
Inflammatory
cytokines
Pathogens
Antioxidants
Vitamin E
Selenium
Lycopene
Green tea
SNPs
DNA repair
Oxidative
enzymes
ROS
Oxidative Stress
Damage to DNA,
RNA, protein and
lipids
Chromosomal
instability, gene
mutations
Altered gene
expression
5. Sample & Assay Technologies
The biological importance of ROS
Physiological positive effects of ROS
Kill microorganism
Second messenger (H2O2)
Cellular differentiation & proliferation
Regulate signal transduction &
transcription
Cytokines and growth factor receptors (EGFR, PDGFR,
VEGFR, receptors of TNFα, IFNγ and IL-1β)
Non-receptor tyrosine kinases (JAK, Src, MAPK and PI3K)
Protein tyrosine phosphatases
Serine/Threonine kinases (Akt, PKC and MAPK)
Nuclear transcription factors (NFκ B, AP-1, NFAT, HIF-1 and
Nrf2)
Oxidative Stress and Oxidative Damage in Carcinogenesis, Toxicologic Pathology, 38: 96-109, 2010
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ROS
PLCγ
PI3K
Akt ATM
NFkB
ERK
JNK
p38
NFAT
JAK
PKC
p53
C-Jun
Nrf2
Gene expression changes
6. Sample & Assay Technologies
Antioxidant defense mechanism
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Inhibit excess ROS formation, capture radicals, maintain redox homeostasis
and correct mechanism of destroyed biomolecules
Mediated through Antioxidant Responsive Element (ARE) sequence
Controlled by nuclear transcription factors Nrf2, AP-1, NFκB, p53, NFAT
ROS Transcription factors
Transcription
ARE AREAntioxidant response elements (AREs)
7. Sample & Assay Technologies
Nrf2-mediated oxidative stress response
Nrf2: Nuclear factor-erythroid 2-related
factor is a basic leucine zipper (bZIP)
transcription factor that binds to ARE to
activate transcription.
Keap1: Kelch-like ECH-associated
protein 1. Keap1 interacts with Nrf2 in a
redox-sensitive manner.
Inactive Nrf2 is retained in the
cytoplasm by association with Keap1.
Upon exposure to oxidative stress, Nrf2
is phosphorylated in response to the
PKC, PI3K, and MAPK pathways. After
phosphorylation, Nrf2 is translocated to
the nucleus, binds AREs, and activates
detoxifying enzymes and antioxidant
enzyme.
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9. Sample & Assay Technologies- 9 -
Antioxidant Action of Vitamin-C
Vitamin-C is a potent antioxidant and a
regulator of redox-signal transduction
Under stress, Vitamin-C acts as a
primary antioxidant in plasma and cells
Vitamin-C quenches ROS and serves
as a cofactor of enzymes involved in
the synthesis of collagen, carnitine
And neurotransmitters
https://www.qiagen.com/geneglobe/pathwa
yview.aspx?pathwayID=34&
10. Sample & Assay Technologies
Oxidative damage of ROS
Aggregation and
fragmentation
Enzyme inhibition
Proteins
DNA strand breaks
Mutations leading
to cancer
DNA
Lipid peroxidation
Damage to
membranes and
lipoproteins
Membrane
ROS
Oxidative stress, disease and aging
Review article: “Molecular targets of oxidative stress” Biochem. J. (2011) 434, 201
What is the cellular targets of ROS that account for the toxicity?
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13. Sample & Assay Technologies
Oxidative stress links chronic inflammation & cancer
Oxidative stress, chronic inflammation, and cancer are closely linked
Free radicals as a link of oxidative stress to inflammation and cancer
Oxidative stressOxidative stress
Carbonylic adducts Hydro & lipoperoxides Imbalance in DNA repair
Imbalance between pro & anti-apoptotic processes, altered gene expression & mutations
Chronic inflammation
Activation of
Inflammatory cells
ROS production
LOXs, COXs, PHGPx iNOS
NFkBCytokines
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14. Sample & Assay Technologies
ROS play multiple roles in the hallmarks of cancers
Review article: “Oxidative Stress, Tumor Microenvironment, and Metabolic Reprogramming: A Diabolic Liaison”
International Journal of Cell Biology. 2012
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15. Sample & Assay Technologies
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Oxidative stress is tightly linked to
mitochondrial dysfunction, and
mitochondria are both generators of
and targets of ROS
In respond to cellular stress,
necrosis, apoptosis and autophagy
are activated.
Mitochondrial turnover is dependent
on autophagy
Dysregulated redox signaling or
mitochondrial dysfunction affect
autophagic activities
Mitochondria are the targets of ROS
Review article: “Autophagy, mitochondria and oxidative stress: cross-talk and redox signaling” Biochem. J. 2012, 441, 523
16. Sample & Assay Technologies
miRNAs are modulators and targets of oxidative stress
“Inflammation and cancer: interweaving microRNA, free radical, cytokine and p53 pathways” Carcinogenesis, 31(1): 37–49, 2010
miRNAs are non-coding RNA molecules that modulate the
stability and/or the translational efficiency of target messenger
RNAs
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“Oxidative Stress and MicroRNAs in Vascular Diseases” Int. J. Mol. Sci. 2013, 14
Relevant miRNAs in oxidative stress response
ROS source
miRNAs
upregulated Tissue/organ Source Target Functions
H2O2 miR-200c
miR-141 endothelium
miR-200a myoblasts Human ZEB1 apoptosis
miR-200b
miR-429
H2O2 miR-200c ROS accumulation;
miR-141 miR-200a ovarian Human p38α improved response to
miR-200b adenocarcinomas chemotherapy
miR-429
H2O2 miR-200c primary Mouse Unknown Unknown
hippocampal
neurons
Obesity miR-200c miR-141 Heart Rat S6K1 compensatory/adaptive
mechanisms
17. Sample & Assay Technologies
Detection of intracellular oxidative stress
Direct approach
Detection of ROS / free radicals
Colorimetric (ROS-dependent reactions),
fluorometric (ROS-sensitive probes)
Challenging: short-lived, highly reactive
molecules
Indirect approach
Antioxidant enzyme activity
Detect oxidative stress damage products
Measure cellular antioxidant capacity
Simple: more stable modifications of
macromolecules
Wide range of techniques
Untreated Cells
Treated Cells
The cell-permeant dye H2-DCF-DA is
non-fluorescent in a reduced state and
exhibits fluorescence upon oxidation by
ROS.
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18. Sample & Assay Technologies
Detection of oxidative damage to macromolecules
Lipid markers of oxidative stress
4-Hydroxynonenal (HNE) is a by-product of lipid peroxidation, widely used as a
marker of chronic oxidative stress
Protein markers of oxidative stress
Protein carbonylation – formation of carbonyl derivatives of Pro, Lys, Arg and Thr
residues – is the most common product of protein oxidation (ELISA assay).
Advanced oxidation protein products (AOPP) are created when proteins react with
chlorinated oxidants.
DNA markers of oxidative stress
8-hydroxydeoxyguanosine (8-OHdG)
Antioxidant assays
Catalase activity, SOD activity
Total antioxidant capacity
GSH levels
Avery SV. Molecular targets of oxidative stress. Biochem J. 2011 Mar 1;434(2):201-10.
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19. Sample & Assay Technologies
Oxidative Stress and ROS Signaling
Overview
Oxidants & antioxidant in biological
systems
Antioxidant defense mechanism
Molecular targets of oxidative stress
Detection of oxidative stress
Research Solutions @ QIAGEN
Gene expression
Epigenetics
Functional studies
Application Examples
19
22. Sample & Assay Technologies
Application 1: gene expression
In response to cellular oxidative stress, pathways including necrosis,
apoptosis, and autophagy will be activated.
.How is cell fate determined under oxidative stress?
FASEB J. 2011 October; 25(10): 3366FASEB J. 2011 October; 25(10): 3366FASEB J. 2011 October; 25(10): 3366
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23. Sample & Assay Technologies
Experiment design
Treat with glucocorticoid
Isolate total RNA
Reverse
transcription
(RT)
Data Analysis
cDNA synthesis
qPCR
Swiss-Webster mice MLO-Y4 cells
Application 1: gene expression
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1-2 pm EST, Feb. 3, 10, 17, 24, Monday, qPCR Technology webinar series
https://www2.gotomeeting.com/register/311390954
24. Sample & Assay Technologies
Pathway-focused RT2 Profiler PCR Arrays
Apoptosis RT2 Profiler PCR Array: 84 genes involved in programmed cell
death
Include: genes involved in induction of apoptosis, anti-apoptosis, regulation of
apoptosis, DEATH domain proteins, caspases and regulators
Autophagy RT2 Profiler PCR Array: 84 genes involved in autophagy
Include: autophagy machinery components, regulation of autophagy
Oxidative stress RT2 Profiler PCR Array: 84 genes involved in oxidative
stress
Application 1: gene expression
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human, mouse, rat, and up to 13 species
27. Sample & Assay Technologies
Application 1: oxidative stress & autophagy
Results:
• Activation of the antioxidant genes positively correlated with activation of the autophagic
genes
• No significant correlation between the activation of antioxidant and antiapoptosis genes
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30. Sample & Assay Technologies
Applications of oxidative stress PCR Arrays
Publications Citing the Oxidative Stress PCR Array
• Susceptibility to Inhaled Flame-Generated Ultrafine Soot in Neonatal and Adult Rat Lungs, TOXICOLOGICAL
SCIENCES 124(2), 472–486 (2011), Jackie K. W. Chan,* Michelle V, etc.
• Adaptive induction of NF-E2-related factor-2-driven antioxidant genes in endothelial cells in response to hyperglycemia,
Am J Physiol Heart Circ Physiol 300: H1133–H1140, 2011, Zoltan Ungvari,1 Lora Bailey-Downs, etc.
• Tryptophan from human milk induces oxidative stress and upregulates the Nrf-2-mediated stress response in human
intestinal cell lines. J Nutr. 2011 Aug;141(8):1417-23. Elisia I, Tsopmo A, Friel JK, etc.
• Age-related gene response of human corneal endothelium to oxidative stress and DNA damage. Invest Ophthalmol Vis
Sci. 2011 Mar 1;52(3):1641-9. Joyce NC, Harris DL, Zhu CC
• Gene expression analysis of oxidative stress and apoptosis in proton-irradiated rat retina. In Vivo. 2010 Jul-
Aug;24(4):425-30. Mao XW, Green LM, Mekonnen T, Lindsey N, Gridley DS
• Increased ANG II sensitivity following recovery from acute kidney injury: role of oxidant stress in skeletal muscle
resistance arteries. Am J Physiol Regul Integr Comp Physiol. 2010 Jun;298(6):R1682-91. Phillips SA, etc.
• Effects of spaceflight on innate immune function and antioxidant gene expression. J Appl Physiol. 2009
Jun;106(6):1935-42. Baqai FP, Gridley DS, Slater JM, Luo-Owen X, Stodieck LS, Ferguson V, etc.
• Oxidative stress: molecular perception and transduction of signals triggering antioxidant gene defenses. Braz J Med Biol
Res. 2005 Jul;38(7):995-1014. Scandalios JG
• Oxidative stress and gene regulation. Free Radic Biol Med. 2000 Feb 1;28(3):463-99. Allen RG, Tresini M
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31. Sample & Assay Technologies
Transcription factors Nrf2 and Nrf1 bind to the antioxidant response
elements (ARE) and regulate genes involved in protecting cells from
oxidative damages.
.How to measure the degree of
antioxidant response?
Application 2: gene functions
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32. Sample & Assay Technologies
Application 2: reporter assays for oxidative stress
Cignal Reporter Assays & Arrays
■ Dual-luciferase format
■ GFP format
■ DNA and Lenti assay
■ 45 signaling pathways
http://www.qiagen.com/search/cignal-reporter-assay-kits
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33. Sample & Assay Technologies
45-pathway array & 10-Pathway Arrays
Single Pathway Assay
Antioxidant Response ReporterCignal Finder Stress & Toxicity 10-pathway reporter Kit
Measure the transcriptional activity of
the Nrf2 (NF-E2-related factor 2) and
Nrf1 transcription factors. Nrf2 and
Nrf1 bind to the antioxidant response
elements (AREs) and regulate genes
involved in protecting cells from
oxidative damage.
Application 2: reporter assays for oxidative stress
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34. Sample & Assay Technologies
Answer two questions:
1.Whether hyperglycemia activates Nrf2 in endothelial cells?
2.Whether induction of Nrf2-regulated ROS detoxification systems protect
endothelial function in type 2 diabetes?
Experiment procedure:
• Treat wild type and Nrf2 knockout mouse with a high-fat diet (HFD) and standard diet
• Use reporter assay to measure Nrf2 activity
Application 2: reporter assays for oxidative stress
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Published data using Cignal reporter assay kit
35. Sample & Assay Technologies
Results & conclusion:
• Hyperglycemia induces oxidative stress
• Adaptive activation of the Nrf2/ARE pathway has a critical role in endothelial protection in response
to diabetic condition both in vitro and in vivo.
Application 2: reporter assays for oxidative stress
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Glucose (mmol/L)
RelativeNrf2induction(foldchange)
Glucose (mmol/L)
RelativemRNAexpression(foldchange)
36. Sample & Assay Technologies
Functional genomics:
Assess RNA interference phenotypes
Assess overexpression phenotypes
Functional proteomics:
Analyze the effects of recombinant protein or peptide treatments
Drug discovery:
Screen and validate small molecule drug candidates
Applications: Cignal reporter assay kits
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Download a white paper “Cignal Reporter Assay Kit: A high-performance tool for assessing
the functions of genes, biologics, and small molecule compounds - (EN)”
http://www.qiagen.com/knowledge-and-support/resource-center/resource-download.aspx?id=6fc8144b-010b-
43d8-9125-bf541a5d9c9c&lang=en
Benefits
Excellent sensitivity and specificity
Maximal signal-to-noise ratio
Minimal background transcription and rapid response
Reduced experimental variation and greater reliability
37. Sample & Assay Technologies
Application 3: antioxidant response mechanism
miRNAs play a regulatory role in Nrf2/Keap1 pathway
How is Keap1 regulated?
What is the mechanism of Nrf2-dependent antioxidant
response in cancer?
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• Dysregulation of the NRF2 signaling pathway is linked to cancer
chemotherapy resistance
• Nrf2 may contribute to tumorigenesis
• Nrf2 as a miRNA transcription factor
• A number of miRNAs are regulated by Nrf2
38. Sample & Assay Technologies
Application 3: miRNA expression profiling
Human breast cancer cell lines MDA-MB-231 and Hs578T, non-tumorigenic
MCF-10A cells
Profiled the expressions of 84 miRNAs using Human miFinder PCR Array
(MIHS-001Z)
Experiment design:
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39. Sample & Assay Technologies
miScript miRNA PCR Arrays
1 hour
2 minutes
2 hours
15 minutes
miFinder miRNA PCR Array
• Profiles the expression of the 84
most abundantly expressed and
best characterized miRNAs in
miRBase (www.miRBase.org);
• Maximize the likelihood of
discovering miRNAs whose
expression patterns correlate with
the biological phenotypes;
• Available in Human, Mouse, Rat,
Dog, Rhesus Macaque, more
miRNA PCR Array
• miFinder
• Serum & Plasma
• Brain Cancer
• Breast Cancer
• Ovarian Cancer
• Prostate Cancer
• Cancer PathwayFinder
• Apoptosis
• Inflammatory Response and
Autoimmunity
Workflow
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40. Sample & Assay Technologies
Application 3: miRNA expression profiling
Conclusion: miR-200a regulates the Keap1/Nrf2 pathway in mammary epithelium ; Epigenetic
therapy can restore the miR-200a regulation of Keap1 expression, therefore to reactivate Nrf2-
dependent antioxidant pathway in breast cancer.
Measured Nrf2 ARE promoter activity using luciferase reporter assay
Epigenetic therapy restored miR-200 expression and reduced Keap1 level
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• miR-200c is a tumor suppressor miRNA, involved in cancers such as breast, ovarian,
endometrial, colorectal cancer, and pancreatic cancer
Normal cell: MCF-10A
Breastcellline:MDA-MB-231
Mature miRNAs Fold changes
has-miRNA-141 -869.07
has-miRNA-200c -422.65
has-miRNA-2302c -66.41
has-miRNA-196b -65.95
has-miRNA-143 -40.32
has-miRNA-122 -18.68
has-miRNA-7f -15.07
… …
41. Sample & Assay Technologies
miRNA assays and reagents from QIAGEN
Target Identification Expression
Isolation
Function
miRNA mimics & inhibitors
miScript miRNA PCR Arrays
miRNeasy
miRNA
Studies
Feb 6-27, Thursday: 4 part miRNA focused webinar series, monthly
https://www2.gotomeeting.com/register/152689794
RT² Profiler™ microRNA
Targets PCR Arrays
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45. Sample & Assay Technologies
Pathway-focused solutions @ QIAGEN
Complete systems: sample prep through data analysis
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http://www.qiagen.com/geneglobe/
46. Sample & Assay Technologies- 46 -
Thank You for Attending!
Are you ready to try?
Contact Technical Support
North America:
• SAB_Support@QIAGEN.com
• techservice-na@qiagen.com
Phone: 1-800-362-7737
International customers:
BRCsupport@qiagen.com
Webinar related questions: Qiawebinars@qiagen.com