inflammation and oxidative stress: a clinical paradox
TRANSCRIPT
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Inflammation and oxidative stress:
a clinical paradox
A paradox involves contradictory yet interrelated elements that exist
simultaneously and persist over time.
Inflammation
• A defensive immune response
• Innate immune system = vasodilation, vascular leakage and leukocyte emigration
• Heat, redness, pain, swelling
• Pathogen/damage associated molecular patterns (PAMPs/DAMPs) recognised by receptors, e.g. TLRs, NLRs, RAGEs, expressed on macrophages, monocytes, dendritic cells and neutrophils
• Secretion of cytokines and chemokines = further immune cell recruitment and inflammatory meditator production
Inflammation – role in chronic illness
• Products of inflammation can damage tissue and cause further stimulation of immune response
• If the inflammatory response continues unnecessarily, this can lead to accumulative damage
• Thus it follows that poorly regulated, prolonged or inappropriate inflammation, also known as chronic or low-grade inflammation (‘silent inflammation’) increases susceptibility to illness and disease
Resoleomics - the process of inflammation resolution In
flam
mat
ory
res
po
nse
Initiation Resolution Termination
PGE2
LTB4
Eicosanoid switch Stop signal
Time
Pro-inflammatory reduced
Anti-inflammatory increased
Oxidative stress • Reactive oxygen species (ROS) are generated as by-products of cellular
metabolism via the electron transport chain, cytochrome P450 and NADPH oxidases
• Produced in response to infection, exercise, pollutant exposure, UV light, ionising radiation, cellular respiration, inflammation, certain drugs, detoxification of xenobiotics, cigarette smoke…
• In healthy humans, production of ROS/RNS is kept in check by our in-built antioxidant defences
• If delicate balance shifts in favour of
pro-oxidants, oxidative stress results
Oxidative stress
• Conventionally – oxidative stress defined as imbalance between pro-oxidant stress and antioxidant defence
• Recently - disruption of redox signalling important – perhaps more so
• Oxidative stress – an imbalance between oxidants and antioxidants in favour of oxidants, leading to disruption of redox signalling and control and/or molecular damage
Kunwar A et al. Free radicals, oxidative
stress and antioxidants in human
health J Med Allied Sci 2011; 1(2)
Oxidative stress – role in illness
• Uncontrolled/excessive ROS leads to potential damage to all biomolecules - most susceptible being proteins, DNA, lipid membranes - leading to functional impairment and cell death
• Free radical damage to – Carbohydrates = chain breaks in molecules such as hyaluronic acid
– DNA = mutations and strand breaks
– Proteins = affects processing and clearance leading to accumulation and build-up in the brain and tissues
• Antioxidants can become pro-oxidants – in presence of reactive metals
– if subsequent antioxidants in the chain not available
– if levels are too high
Oxidative stress
Cancer
Atherosclerosis
Diabetes
Fatty liver diseaseAgeing
Arthritis
Neurological disease
Interdependence
• Experimental data show simultaneous existence of low-grade chronic inflammation and oxidative stress in – Diabetic complications
– CVD
– Neurodegenerative disease
– Liver disease
– Kidney disease
Inflammation causes oxidative stress
• Production of ROS is central to progression of inflammatory disease
• ROS produced by cells involved in inflammatory response (polymorphonuclear neutrophils) - act as signalling molecules and inflammatory mediator
• At sites of inflammation activated inflammatory cells release ROS & RNS as well as enzymes and chemical mediators, resulting in tissue damage and oxidative stress
• When TLR/NLR/RAGE bind PAMPs = transcription factor activation and proinflammatory gene expression – co-stimulation of several TRLs in the presence of cytokine imbalance results in ROS generation
• INF-γ and LPS synergistically increase ROS production
• Macrophages (M1) produce excessive oxidative stress to eliminate pathogens by inducing cell death via caspase activation and creating an imbalance in glutathione equilibrium
Oxidative stress causes inflammation
• Pro-oxidants can initiate intracellular signalling cascades that enhance proinflammatory gene expression
• NF-ƘB – a key player in the inflammatory cascade is stimulated by oxidative stress and intracellular redox status
• ROS released from damaged mitochondria can activate NLRP3 inflammasomes, leading to IL-1β expression
• Oxidatively damaged DNA induces a signalling cascade that culminates in proinflammatory gene expression and cell accumulation
• 8-isoprostane – an arachidonic acid peroxidation end product and a marker of oxidative stress - increases expression of proinflammatory IL-8
• Oxidation of plasma cysteine triggers monocyte adhesion to the vascular endothelium = activation of NF-ƘB and expression of IL-1β
When oxidative stress appears as a primary disorder inflammation develops as a secondary
disorder and further enhances oxidative stress. On the other hand, inflammation as a primary
disorder can induce oxidative stress as a secondary disorder which can further enhance
inflammation.
Biswas SK. Does the Interdependence between Oxidative Stress and
Inflammation Explain the Antioxidant Paradox? Oxid Med Cell Longev.
2016;2016:5698931. doi: 10.1155/2016/5698931.
Nutritional approaches to inflammation
The key to regulating inflammation is through the modulation of eicosanoids
• pro-inflammatory eicosanoids drive the immune and inflammatory processes
• anti-inflammatory eicosanoids act to end the process
Overproduction of pro-inflammatory products or reduced production of anti-inflammatory products can result in continued production of inflammatory products – the hallmark of silent inflammation
• Eicosanoids are derived from omega-6 and omega-3 polyunsaturated fats
• The ratio of omega-6 to omega-3 in the diet influences the type of
eicosanoid produced
Arachidonic acid gives rise to key pro-inflammatory mediators (via COX-2) involved in orchestrating crosstalk between cells involved in the regulation of the immune and inflammatory response
Therefore by regulating arachidonic acid levels within cell membranes we can reduce the production of pro-inflammatory eicosanoids and inflammatory mediators
– Prostaglandins
– Thromboxanes
– Leukotrienes
– Cytokines
Omega-6LA
Omega-6GLA
Omega-6DGLA
Omega-3ALA
Omega-3EPA
Omega-3SDA
Anti-inflammatory eicosanoids
Anti-inflammatory eicosanoids
When omega-3 intake is low, the omega-6 pathway converts DGLA to AA, resulting in a corresponding increase in inflammatory
products from AA known as the ‘the arachidonic acid cascade’
INFLAMMATION
Pro-inflammatory leukotriene
Pro-inflammatory thromboxane
Pro-inflammatory prostaglandin
Omega-6 AA
Reduced inflammation
delta-6 desaturase
(FADS2)
delta-5 desaturase(FADS1)
Omega-6LA
Omega-6GLA
Omega-6DGLA
Omega-3ALA
Omega-3EPA
Omega-3SDA
Omega-3DHA
Omega-6AA
delta-6 desaturase(FADS2)
Omega-6 Omega-3
Omega-6LA
Omega-6GLA
Omega-6DGLA
Omega-3ALA
Omega-3EPA
Omega-3SDA
Omega-3DHA
Omega-6AA
delta-6 desaturase(FADS2)
Nutritional approaches to oxidative stress
Antioxidants
• Substances that neutralise free radicals or their actions – endogenous and exogenous sources
• Enzymatic: superoxide dismutase, glutathione peroxidase, glutathione reductase, thioredoxin, thiols and disulfide bonding – act as cellular redox buffers
• Non-enzymatic: α-tocopherol (Vit E), ascorbate (Vit C), carotenoids, flavonoids, polyphenols, α-lipoic acid, glutathione……
• Act at different stages of the process:
1. Prevention – stop the formation of ROS/RNS (e.g. SOD)
2. Interception – mainly free radical scavenging (‘typical’ antioxidants)
3. Repair – reconstitute and repair damaged target molecules (enzymes e.g. methionine-S-sulfoxide reductase A)
Epidemiological studies show inverse correlation between tissue/plasma antioxidant and phytonutrient status and chronic illness and mortality
Omega-3 index above 8% = significant reduction in all-cause mortality
Diet rich in plant matter (>5-a-day) and oily fish is known to confer significant protective health benefits
But – lots of negative results
Inconsistencies arising from omega-3 intervention studies give mixed results and create confusing messages (Von Schacky 2015; Harris 2015)
Poor heterogeneity in study designs, background diets, endpoint definitions, and baseline fish or omega−3 fatty acid intakes cloud meta-analysis outcomes
Patients recruited regardless of their baseline levels and treated with fixed doses
Recent RCTs (virtually all of which have been conducted in European or North American cohorts [low dietary fish intakes]) use relatively low doses (376–850 mg EPA & DHA) which at least partly explains their failure
CVD secondary-prevention populations - include many individuals who are already taking multiple heart medications such as statins, aspirin and ACE inhibitors, which may obscure the effect of omega-3 fatty acids
The inter-individual variability in response to a fixed dose of EPA + DHA has been found to be large, i.e. to vary up to a factor of 13
Not all ‘fish oils’ are the same - addressing quality/concentration and purity
Study design to incorporate use of biomarkers?
Biomed J Vol. 37 No. 3 May -
June 2014
“antioxidants should be beneficial when given to the right subject at the right
time”
Essential role of inflammation
• Wound healing
• Pathogen elimination
• Reduced mobility & pain = protective
• Trigger for adaptive immune response
Essential role of oxidative stress
• Act as signalling molecules e.g. NO.
• Necessary for stimulating adaptation processes
• Trigger transcription of antioxidant genes
• H2O2 critical for thyroxine synthesis – needed to catalyse binding of iodine to thyroglobulin
• Trigger for apoptosis
• Detoxification via CYP450
• Stimulation of mitochondrial biogenesis
Suppressing inflammation or ROS/oxidative stress too early/aggressively/chronically can
lead to significant exacerbation and/or extension of symptoms and condition
Husson MO, Ley D, Portal C, Gottrand M, Hueso T, Desseyn JL, Gottrand F. Modulation of host defence against bacterial and viral infections by omega-3 polyunsaturated fatty acids. J Infect. 2016 Oct 14. pii: S0163-4453(16)30252-3.
Key messages
• 0.5 g/day EPA + DHA daily improves the outcome of experimental infections caused by opportunistic extracellular pathogens, which induce a strong inflammatory response, including P. aeruginosa, S. aureus, H. pylori, S. pneumonia, E. coli, Streptococcus B in healthy humans
• By contrast, n-3 LC-PUFA supplementation at a 1-2g daily shown to be detrimental in the outcome of C. rodentium or H. hepaticus colitis, and worsened S. aureus infections as skin abscesses (animals)
• In addition, omega-3 supplementation is detrimental in respiratory, systemic, ocular infections with intracellular pathogens such as M. tuberculosis, Influenza A virus, Salmonella spp., L. monocytogenes, and Herpes simplex virus, which need an immune cell response to eradicate infected cells
• In these infections omega-3 are deleterious because of their immunosuppressive properties
• Omega-3 supplementation during infection may prove detrimental, because of the anti-inflammatory properties, when the host inflammatory response is critical for survival
• Host protection against Influenza A virus requires neutrophils, NK cells, T lymphocytes, and secretion of both inflammatory and antiviral cytokines – omega-3, by actively over-suppressing NK cell numbers can lower the immune system’s ability to combat infections
Michael Ristow et al. Antioxidants prevent health-promoting effects of physical
exercise in humans
Recent work suggests that biological context may be key to predicting
whether antioxidants impede or even promote tumorigenesis.
CAUTION!In presence of oxidative stress lipids are
peroxidised – adding high concentration, high dose long-chain, omega-3s to a pro-oxidant
environment is just fanning the flames
Lipid peroxidation• Membrane lipids are highly susceptible to oxidative damage
• When reacted with ROS = chain reaction ‘lipid peroxidation’
• Numerous toxic by-products formed
- can have wide reacting, systemic effects as secondary messengers
- damage is highly detrimental to cell function
• Termination = reaction of the lipid radical with an antioxidant forming a less reactive molecule
Only 1% oxidised DHA was sufficient to reverse protective
effect of DHA and to significantly increase Aβ production.
Results: Lipid peroxidation was greater in MDD than in controls (studies =17, N=857
MDD/782 control, SMD =0.83 [0.56–1.09], z=6.11, P,0.01, I2 =84.0%) and was
correlated with greater depressive symptom severity (B=0.05, df=8, P,0.01).
Antidepressant treatment was associated with a reduction in lipid peroxidation in MDD
patients (studies=5, N=222, SMD=0.71 [0.40–0.97], P,0.01; I 2 =42.5%).
Ensuring safe interventions
DIET!
https://truphys.com/antioxidants-and-training/
Testing
• Omega-3 index and AA: EPA– Igennus Opti-O-3
• Oxidative stress– Mitochondrial function
– Antioxidant status – CoQ10, GSH,
– Enzyme cofactors – Zn, Se, Cu ….
• SNPs– Covered in my July webinar
Q1 Q2 Q3 Q4 Q5
Low Average HighSaturated fat
Myristic acid 14:0 0.17 0.47 0.62 0.85 2.01
Palmitic acid 16:0 15.5 21.55 23.01 24.38 29.26
Stearic acid 18:0 1.45 13.17 14.48 15.62 23.07
Arachidic acid 20:0 0.05 0.14 0.16 0.18 0.75Behenic acid 22:0 0.15 0.36 0.43 0.51 1.13
Lignoceric acid 24:0 0.19 0.51 0.64 0.76 2.36
Monounsaturated fat
Palmitoleic acid n-7 16:1 0.1 0.69 0.92 1.28 3.51
Oleic acid n-9 18:1 12.38 17.96 21.03 32.97 32.97
Eicosenoic acid n-9 20:1 0.08 0.18 0.22 0.26 0.85
Nervonic acid n-9 24:1 0.07 0.4 0.051 0.65 1.69Polyunsaturated fat n-6Linoleic acid (LA) 18:2 11.08 16.83 18.56 21.15 28.74
Gamma-linolenic acid (GLA) 18:3 0.02 0.13 0.18 0.27 0.97Eicosadienoic acid (EDA) 20:2 0.10 0.16 0.19 0.22 0.98
Dihomo-gamma linolenic acid (DGLA) 20:3 0.39 0.99 1.23 1.48 2.47
Arachidonic acid (AA) 20:4 2.5 8.56 10.05 11.38 16.51
Docosatetraenoic acid n-6 22:4 0.12 0.64 0.85 1.13 2.58
Docosapentaenoic acid n-6 22:5 0.03 0.14 0.17 0.23 1.53
Polyunsaturated fat n-3Alpha-linolenic acid (ALA) 18:3 0.16 0.34 0.41 0.51 1.4
Eicosapentaenoic acid (EPA) 20:5 0.2 0.86 1.4 2.44 10.68
Docosapentaenoic (DPA) 22:5 0.41 0.89 1.11 1.45 3.97
Docosahexaenoic acid (DHA) 22:6 0.96 2.49 3.35 4.37 8.89
Trans fatTrans palmitoleic acid n-7 16:1 0.11 0.19 0.23 0.28 0.84
Trans oleic acid n-9 18:1 0.01 0.09 0.12 0,18 0.54Trans linoleic acid n-6 18:2 0.07 0.16 0.19 0.23 1.7
Targeted nutrient interventions
Anti-inflammatory eicosanoid production
DGLA
GLA
LA
EPA
ETA
SDA
ALA
Delta -6 desaturase
Delta -5 desaturase
Cyclooxygenase (COX)/lipoxygenase (LOX)
Elongase
Series-2 prostaglandinsSeries-2 thromboxanesSeries-4 leukotrienes Hydroxy fatty acids
AA
COX/LOX
Omega-6 Omega-3 Eicosanoids, including prostaglandins and leukotrienes, are biologically active lipids derived from AA and EPA that have been implicated in various pathological processes, such as inflammation and cancer
The relationship between AA and EPA is therefore significant when considering omega-3 intervention strategies
Key structural role & anti-inflammatory
docosanoid productionResolvins Protectins
DHAElongase &desaturase
Pro-inflammatory eicosanoid production
Series-3 prostaglandinsSeries-3 thromboxanesSeries-5 leukotrienes Hydroxy fatty acids
Resolvins
Primary structural function & anti-inflammatory docosanoid
production
Anti-inflammatory eicosanoid production
REDUCED INFLAMMATION
DHAEPA
Pro-inflammatory eicosanoid production
INFLAMMATION
AA
AA to EPA ratiodirect antagonism
The relationship between the omega-3 index and the AA to EPA ratio
Omega-3 index
Is there an optimal EPA to DHA ratio?
2:1 EPA to DHA proportions demonstrated to be more effective treatments to produce an anti-inflammatory response compared with 1:2 EPA to DHA
6 :1 EPA to DHA ratio may be optimal for correcting omega-3 deficiency, with concomitant positive effects on lipid profiles and on inflammatory indices
EPA in excess of DHA is optimal!
As much as 13% of DHA is retro-converted to EPA
Monitor DHA levels and supplement accordingly
Dasilva G, Pazos M, García-Egido E, Pérez-Jiménez J, Torres JL, Giralt M, Nogués MR, Medina I. Lipiomics to analyse the influence of diets with different ratios of EPA to DHA in the progression of metabolic syndrome using SHTOB rats. Food Chem. 2016 Aug 15;205:196-203.
Shaikh NA, Yantha J, Shaikh S, Rowe W, Laidlaw M, Cockerline C, Ali A, Holub B, Jackowski G: Efficacy of a unique omega-3 formulation on the correction of nutritional deficiency and its effects on cardiovascular disease risk factors in a randomized controlled VASCAZEN((R)) REVEAL Trial. Molecular and cellular biochemistry 2014, 396:9-22.
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Curcumin can modulate various types of signalling molecules including transcription factors, enzymes, growth factors, interleukins, cytokines & chemokines
Ghosh S, Banerjee S, Sil PC. The beneficial role of curcumin on inflammation, diabetes and neurodegenerative disease: A recent update. Food Chem Toxicol. 2015 Sep;83:111-24.
NF-κB in chronic disease – a target for nutritional intervention
Potent antioxidant effects– curcumin’s antioxidant mechanisms protect cells against oxidative damage
Improves liver function – curcumin regulates the activity of a number of key enzymes and antioxidants essential for optimal detoxification
Cardiovascular health – curcumin promotes cardiovascular health and function, and protects low density lipoprotein (LDL) from oxidation
Immune health – curcumin improves and supports immune function
Joint health – curcumin significantly improves joint health by reducing inflammation and promoting joint comfort and flexibility
Digestive health – curcumin stimulates bile production and promotes healthy digestive function
Anti-cancer benefits – curcumin offers protective benefits against the main hallmarks of cancer including angiogenesis, proliferation, metastasis, inflammation and apoptosis
Curcumin clinical benefits
• CoQ10 is a powerful, fat-soluble, vitamin-like substance
• Two main functions:• energy production – cellular respiration• antioxidant recycling
CoQ10 - as ubiquinol
• Ubiquinone – oxidised form
• Ubiquinol – reduced form
• 96% of CoQ10 within the body is in the form of ubiquinol
• Ubiquinol is the active form of CoQ10
A free radical has an electron missing from its outer shell
X
Ubiquinol donates anelectron to a free radical
X
Ubiquinol donates electrons to other
antioxidants
‘Recharged’ antioxidants (i.e. vitamins C & E, lipoic acid) can
donate electrons to free radical
Free radical damage and
oxidative stressSkin
LungsInflammation
Cardiovascular
Brain
Immunity
Organs
Ubiquinol deficiency alters mitochondria function and lowers antioxidant status, leading to increased free radical generation
Ubiquinol routinely outperforms ubiquinone
Supplementation with 150 mg/ day ubiquinol for 14 days reduces inflammatory processes via gene expression
Oral intake of ubiquinol increased its proportion significantly (P < 0.001), with the highest increase in those persons having a low basal serum ubiquinol content (<92.3%)
Ubiquinol status significantly correlated to the concentration of the inflammation marker monocyte chemotactic protein 1 (involved in the accumulation of inflammatory cells).CoQ10 redox state predicts the concentration of C-reactive protein (CRP)
People with lower ubiquinol status, higher BMI, and low-grade inflammation may benefit from ubiquinol supplementation
Fischer A1, Onur S1, Niklowitz P2, Menke T2, Laudes M3, Döring F1. Coenzyme Q10 redox state predicts the concentration of c-reactive protein in a large Caucasian cohort. Biofactors. 2016 Feb 23. doi: 10.1002/biof.1269. [Epub ahead of print]
Fischer A, Onur S, Schmelzer C, Döring F. Ubiquinol decreases monocytic expression and DNA methylation of the pro-inflammatory chemokine ligand 2 gene in humans. BMC Res Notes. 2012 Oct 1;5:540. doi: 10.1186/1756-0500-5-540.
CoQ10 supplementation significantly reduced the levels of circulating
CRP (P = 0.022), IL-6 (P = 0.002) and TNF- (P = 0.027). The results of
meta-regression showed that the changes of CRP were independent of
baseline CRP, treatment duration, dosage, and patient characteristics. In
the meta-regression analyses, a higher baseline IL-6 level was
significantly associated with greater effects of CoQ10 on IL-6 levels.
Resveratrol
Combination therapies
Studies are beginning to show that targeted combination therapies elicit greater benefits than single nutrients
Addressing multiple factors/pathways involved in disease onset and progression simultaneously helps overcome clinical paradox effect
Other things to consider
• Remove the root cause
- Importance of finding the triggers
- Removing mediators
• Address collateral damage
– Once the body is primed to react any exposure could re-trigger disease/symptoms
– Managing and maintaining inflammatory balance and anti-oxidant status vital
Triggers and mediators
• Systems under stress – Gut pathology/permeability
– Food intolerance
– Infections
– Hormone imbalance
– Liver function
• Environment and lifestyle– Nutrient imbalance
– Heavy metal toxicity
– Stress
– Poor sleep
Summary – key messages
• Human beings are multi-system organisms
• The complexity of each biological process and how they relate is still not fully understood
• Multi-pronged approach to disease and dysfunction necessary to elicit benefits
• Understanding of mechanisms of action and inter-individual variation essential for therapeutic success
Summary – plan of action
• Know your environment - oxidative stress/inflammation -severity
• What are you combating – specific condition, dysfunction, system
• Identify need – testing
• Lay the foundations – dietary modification
• Targeted interventions – choose proven nutrients for specific, identified issues
• Low dose, high bioavailability/quality
• Co-supplementation for ‘bigger picture’ support
• Ongoing management to address ATMs
Education Technical
Sophie TullyNutrition Education Manager
Dr Nina Bailey Head of Nutrition
[email protected] @DrNinaBailey