Genetics. Unravelling The Mysteries Of Methylation & Part 1. Introduction. September Making Use Of These Developments

Transcription

1 Unravelling The Mysteries Of Methylation & Genetics Part 1 Warren Maginn BHSc (Nutr. Med.) GradCert (Hum. Nutr.) for 1 Introduction We are on the brink of the omics revolution The Genome The Metabolome The Microbiome 2 Making Use Of These Developments Understanding these developments and making focussed stepwise interventions is the primary path to advancing the field of medicine For This We Need: Evidence (through public research AND private clinical testing) Protocols (practical interventions for diet, lifestyle, supplementation, environment and thought, to improve the overall picture) 3 1

2 Where To Focus? Methylation is likely at the centre of it all Along With A Few Other Key Parameters: e.g. Fat/Lipid metabolism & Lipoproteins (ApoE) Inflammation & Oxidation Detoxification Vitamin D Activity Hormone (Estrogen) Metabolism 4 What is Methylation? 5...What is Life? 6 2

3 (Carbon and Water) 7 The Methyl Unit (Single Carbon) 8 All Life = The Exchange & Acquisition of Carbon 9 3

4 The Methylation Cycle (The Exchange Of Carbon) SAMe e.g. DNA / RNA Lipids Neurotransmitters Hormones Toxins 10 Roles Of Methylation In The Body 400+ Enzymatic & Cellular Reactions... DNA Synthesis & Repair Cell Replication & Repair (e.g. fetal development) Neurotransmitter Synthesis and Metabolism Energy Production / Metabolism Hormone Regulation Detoxification Epigenetic Gene Expression / Regulation Telomere Integrity 11 What Can Go Wrong? Insufficient (or Imbalanced) Cofactors to ACTIVATE methylation Insufficient (or Imbalanced) Cofactors to INACTIVATE methylation Too many SUBSTRATES to methylate (can turn Methylation off via feedback inhibition) 12 4

5 The Methylation Cycle (The Role of Folate) 13 The Methylation Cycle (The Role of Folate) Folate B12 * The Folate Cycle is directly connected to the Methylation cycle 14 Methylation In Disease & Aging 15 5

6 Anaemia Red Blood Cells require carbon groups to form Haemoglobin protein needs an Iron atom to function (being a Porphyrin) 16 Cardiovascular Disease Homocysteine requires methylating to Methionine * HIGH Homocysteine is a marker of LOW Methylation 17 Cardiovascular Disease Elevated levels of Homocysteine correlate with a wide range of health disorders (esp. vascular) including: o Atherosclerosis o Myocardial Infarction o Stroke PlasmaFolate is inversely correlated with Hcys levels Suggests Folate levels can alter CVD risk Homocysteine Studies Collaboration, Homocysteine and Risk of Ischemic Heart Disease and Stroke. JAMA. 18 6

7 CVD is also substantially an issue of: LIPID METABOLISM INFLAMMATION & OXIDATION Cardiovascular Disease Our Primary Antioxidative Lipid Defence is: GLUTATHIONE 19 Anti Oxidation and Detoxification 20 Anti Oxidation and Detoxification Trans Methylation M Trans Sulphation S Glutathionation B6 Bile Sulfation 21 7

8 Sulphur Amino Acids Responsible for Lipid Metabolism? An association between the sulfur amino acids (methionine, cysteine, homocysteine and taurine) and lipid metabolism has been described in several experimental and population based studies recent evidence has suggested that the enzyme stearoyl CoA desaturase 1 (SCD 1) may be the link between these two metabolic pathways 22 Toxins & Methylation Trans Methylation M Mercury Lead Aluminium Trans Sulphation S Lead Bile Sulfation Glutathionation 23 How Do We Detox? Fat Soluble Toxins are: stored in fat tissue Water Soluble Toxins can be: directly eliminated via Kidneys or Lungs Excretion occurs via: Respiratory, Digestive & Dermal routes Primary Route is via the Liver 24 8

9 Major Sources of Toxicity Excessive Amounts Of: Caffeine, Alcohol, Nicotine & Medications Food Production / Additives / Packaging Mining & Energy Production / Consumption Bodycare Products Vehicle Pollution Occupational Chemicals Lack Of Exercise Liver / Intestinal Dysfunction Moulds & Microflora 25 Liver Detoxification 26 Anti Oxidation and Detoxification M S GSH Conjugates SOD GGT Toxins GST B6 Bile, (Detox) Sulfation, (Detox) (Antiox / Detox) Glutathionation 27 9

10 Liver Detoxification 26

11 Anti Oxidation and Detoxification Phase II Metabolic Pathways of the Liver Glutathione * Sulfation * Amino * Acid Glucuronidation Acetylation Methylation * NAC/Protein Sulfate Salts Conjugation D-Glucarate Vitamin B5 Folate Selenium Silymarin Vitamin B6 Cysteine ALA Vitamin B6 Glycine Taurine Bifido Probiotics Magnesium Vitamin B6 Vitamin B12 Vitamin B6 Lipid Peroxides Estrogen Prostaglandins Testosterone Leukotrienes Thyroxine Petro-Chems Cortisol Alcohol Adrenaline Paracetamol Melatonin Heavy Metals DHEA Bacterial Toxins Fungal Toxins Bile Acids Salicylates Benzenes Steroid Hormones (Estrogen, T, Prog.) Fat Sol. Vitamins (Vitamin A & D) Fat Sol. Toxins (Plastics / Pesticides) Histamine Choline Hormones Heavy Metals Neurotrans. Serotonin Melatonin Dopamine Epinephrine DNA Regulation Cell Regen. 28 Glutathione Levels with Age Erden Inal et al Age related changes in the glutathione redox system. Cell Biochem. 29 Histamine Excessive levels can lead to: Symptoms Migraine / Headache Depression / Dizziness Gastrointestinal complaints Tachycardia, Arrhythmia Hypotension Excessive Menstrual Pain Rhinitis / Asthma Skin Irritation Causes Immune Reactions (IgE) Imbalanced Gut Flora Excess Dietary Intake Vitamin B6 Deficiency Insufficient DAO Enzyme Insufficient Methylation 30 10

12 Anti Oxidation and Detoxification Phase II Metabolic Pathways of the Liver * * * * Glutathione NAC/Protein Selenium Silymarin Vitamin B6 Sulfation Sulfate Salts Cysteine ALA Vitamin B6 Amino Acid Conjugation Glycine Taurine Glucuronidation D-Glucarate Bifido Probiotics Acetylation Vitamin B5 Magnesium Vitamin B6 Methylation Folate Vitamin B12 Vitamin B6 Lipid Peroxides Prostaglandins Leukotrienes Petro-Chems Alcohol Paracetamol Heavy Metals Bacterial Toxins Fungal Toxins Estrogen Testosterone Thyroxine Cortisol Adrenaline Melatonin DHEA Bile Acids Salicylates Benzenes Steroid Hormones (Estrogen, T, Prog.) Fat Sol. Vitamins (Vitamin A & D) Fat Sol. Toxins (Plastics / Pesticides) Histamine Choline Hormones Heavy Metals Neurotrans. Serotonin Melatonin Dopamine Epinephrine DNA Regulation Cell Regen. 28

13 Methylation & Histamine B12, Folate (SAMe) B6 B6, Cu Schwelberger Metabolism of Histamine 31 Methylation & The Nervous System 32 Nervous System Integrity Evidence is presented to demonstrate an involvement of... methylation in the integrity and maintenance of Myelin

14 Methylation & Histamine B6 B12, Folate (SAMe) B6, Cu Schwelberger Metabolism of Histamine 31

15 Neural Tube Formation CDC Methylation & The Stress Response 35 ACTH & Methylation It has been shown: 1. Protein carboxy methylation and phospholipid methylation occur during CRF stimulation of ACTH release 2. ACTH itself is methylated 3. ACTH then affects numerous subsequent methyl pathways: (e.g. Decreases the methylation of Nicotinamide, decreases the conversion of Phenylalanine to Tyrosine, etc.) 1. De Souza & Nemeroff Corticotropin Releasing Factor Basic and Clinical Studies of a Neuropeptide 2. Kim and Li Enzymatic methyl esterification of specific glutamyl residue in corticotropin 3. Hunter Effect of ACTH Administration on Certain Enzyme Systems in Rat Liver

16 The Alternate Route 37 The Alternate Route Phospholipid Membrane Phosphatidylethanolamine Phosphatidylcholine Diet 38 The Cortisol Conundrum Cortisol the ultimate facilitator of stress responses Production depends on methylation Low methylation = increased demand for Cortisol (esp. via Histamine) But excess Cortisol can decrease Glutathione Accelerated aging can result from oxidative stress (Suboptimal methylation = low cellular regeneration) Too many stressors = too many demands on methylation 39 13

17 Methylation & Mental Health 40 NT Synthesis & Metabolism Methylation Required For: Synthesis of Serotonin and Dopamine (via BH4 activity) Conversion of Dopamine to Catecholamines N.B. Low Dopamine levels associated with poor concentration, impaired memory, ADHD, Parkinson s, Depression etc. Low Serotonin / Melatonin associated with Depression, Sleep/Fatigue disorders, Digestive Complications 41 The Link Between Folate & BH4 (For NT Production) SAMe BH4 Norepinephrine Epinephrine Melatonin Dopamine Serotonin * BH4 Cycle directly related to the Folate & Methylation cycle 42 14

18 BH4 BH4 Dopamine Pathway Phenylalanine Tyrosine L Dopa. Serotonin Pathway Tryptophan 5 HTP BH4 Dopamine Serotonin SAMe Norepinephrine SAMe Epinephrine Melatonin 43 Melatonin Production As We Age Peuhkuri,Sihvola, Korpela, Dietary factors and fluctuating levels of melatonin. 44 Incidence Of Age Related Mental Health Issues Cognitive Decline Increased plasma homocysteine level is a strong, independent risk factor for the development of dementia and Alzheimer's disease

19 Depression There is a high incidence of post stroke depression And this occurs equally often during the first year after stroke and after myocardial infarction 46 Autism Spectrum? 47 Steroid Hormones Oestrogens & Cancer 48 16

20 Steroid Hormones Oestrogens & Cancer 48

21 CFS The Glutathione Depletion Methylation Cycle Block (GD MCB) Hypothesis 1. Individual inherits a genetic predisposition (SNPs) toward developing CFS 2. Then experiences some combination of possible stressors (physical, chemical, biological, psychological/emotional) that place demands on glutathione. 3. Glutathione levels drop, producing oxidative stress, removing protection of B12, allowing toxins to accumulate, and shifting immune response to Th2. 4. Toxins react with B12, lowering the rate of conversion to methylcobalamin. 5. Lack of sufficient methylcobalamin inhibits methionine synthase, placing a partial block in the methylation cycle. 6. Sulfur metabolites drain through the transsulfuration pathway excessively, via sulfoxidation, and are excreted (instead of to GSH formation). 7. A vicious circle is established between the methylation cycle block and the glutathione depletion, and the disorder becomes chronic. Rich Van Konynenburg, Ph.D. 49 Lymes Dx & CFS (The Proposed Link) Depletion of Glutathione by Borrelia burgdorferi 1. Bb requires cysteine for its metabolism. 2. Cysteine is the rate limiting amino acid for the synthesis of glutathione in humans, thus depletion of cysteine will yield depletion of glutathione. 3. This will inhibit the activity of glutathione peroxidase. 4. Which increases H202 and oxidative stress. 5. Elevated H202 causes Bb to assume its cyst form, (in which it is less vulnerable to antibiotics) 6. If Bb and its biotoxin are not eliminated, Lyme disease and CFS would coexist in the host, and this would constitute "chronic Lyme disease." 7. If Bb and its biotoxin were successfully eliminated, but the methylation cycle block continued, the person would still continue to be ill with CFS Rich Van Konynenburg, Ph.D. 50 Medications (Chronic Conditions) Increased likelihood of polypharmacy with age Numerous drugs known to inhibit the body s utilisation of Folate, (and potentially compound symptoms?), including: Aspirin Statins OCP Antacids Methotrexate

22 SUMMARY Relevance of Methylation to Health 52 Methylation Often Acts To Silence (Inactivate or Detoxify) Homocysteine (can be toxic) Dopamine (a stimulant) Cytosine (of an oncogene) Methyl Methyl Methyl MTR COMT DNMT Methyl-Homocysteine (Methionine a harmless amino acid) Methyl-Dopamine (5-MT) (Non-stimulating, nontoxic, easily excreted) 5-Methyl-Cytosine (gene silencing) 53 Conditions That Might Benefit From Methylation Support Fertility / Prenatal Care Autism, ADHD Depression / CFS / Fibromylagia / Lymes Cognitive Decline (Parkinson's, Alzheimer's) Neuropsychiatric Disorders (Schizophrenia) CVD (MI, Atherosclerosis, Stroke) Cancer (prevention and/or treatment) Increasingly Important with Advancing Age 54 18

23 TREATMENT STRATEGIES (Supporting Methylation) 55 Folate How Deficiency Occurs Low dietary intake Poor intestinal absorption of ingested folate Increased use (i.e. physical activity, pregnancy) Folate dysmetabolism, due to: Medication interactions Liver conditions Genetic variations Halsted, 1989, Wright et al., Folate Dietary Reference Intake 57 19

24 Dietary Folate Intake (Europe) Problems With Folate Supplementation 60 20

25 Forms Of Folate Folic Acid Is Not Folate! Folic acid: Synthetic Very Stable Less readily metabolised more prone to bio accumulation (Accumulation can obstruct other folate intermediates/actions) Folates (DHF, Folinic, 5MTHF): Naturally Formed Relatively Unstable (e.g. cooking) Relatively easier to metabolise Metabolic blocks still occur (Due to genetics, toxicity, nutr. def..) 61 5MTHF Absorption Folic vs 5MTHF FOLIC 62 Conversion Folic vs Folinic Acid / 5 MTHF 63 21

26 Conversion Folic vs Folinic Acid / 5 MTHF 63

27 Folic Acid Conversion Folic, Folinic & 5 MTHF B3 * * B3 Folinic Acid MTHFR B2 5-MTHF 64 Folic Acid vs 5 FTHF / 5 MTHF Folic Acid: Unmetabolised amounts can obstruct methylation Metabolised portion may not cross BBB Potential increased cancer risk Can mask B12 deficiency (esp. with age) Folinic Acid & 5 MTHF: Readily metabolised (bypasses numerous metabolic blocks) More effective on neurological components (behind BBB) Used in cancer treatment Less likely to mask B12 deficiency Hirsch et al. 2009, Eur J Gastroenterol Hepatol. Stec et. al AlphaMed Press. 65 UMFs Folate Traps METHOTREXATE B12 Deficiency?! 66 22

28 Folic Acid & Cancer Risks? Folic acid can potentially act as a cellular growth factor Increased risk of cancers have been indicated (esp. colorectal) Widespread Folic fortification / supplementation implicated Hirsch et al Colon cancer in Chile before and after the start of the flour fortification program with folic acid. Eur J Gastroenterol Hepatol. 67 Depressed red blood cell folate is associated with an increased risk of dysplasia and cancer in patients with ulcerative colitis and may be a risk factor for neoplastic transformation Serum folate, reflecting short term stores, was not different between groups. 68 Research seeking to confirm is conflicting (too many factors?) Stevens et. al High Levels of Folate From Supplements and Fortification Are Not Associated With Increased Risk of Colorectal Cancer Folic acid supplementation does not substantially increase or decrease incidence of site specific cancer during the first 5 years of treatment 69 23

29 2014 Our data suggest that folic acid supplementation may promote the progression of established mammary tumors. The potential tumorpromoting effect of folic acid supplementation in breast cancer patients and survivors needs further clarification. 70 Unmetabolised Folic Acid & Cancer Unmetabolised serum Folic Acid has been associated with decreased Natural Killer cytotoxicity Natural Killer cells play known role in tumor cell destruction Suggests another mechanism for Folic Acid (to promote existing premalignant and malignant lesions) Folinic Acid Folinic Acid is successfully used in standard cancer treatment (Folinic Acid readily converts to 5 MTHF without obstructive by products) Troen et. al J. Nutr. Stec et. al Under & Over Methylation: An Over Simplification? Body regulates methylation up and down locally (according to needs and risks) Upregulation is restricted by limits of capacity We need to support capacity where it is insufficient BUT not overwhelm where it is beneficially downregulated Balance Is Key How Do We Know What To Do? 72 24

30 Clinical Testing (How To Assess) 73 Testing Issues Standard Serum/Red Cell Folate testing: Does not show break down of multiple Folate forms (Can mask excess accumulation/metabolic dysfunction) Can therefore give false negatives (of functional deficiency) Does not necessarily assess levels in the CNS Testing Homocysteine alone: Homocysteine levels subject to innumerable factors Cannot distinguish between poor methylation or sulfation (Can give false negatives if TransSulfation is upregulated) i.e. Hard to draw approp. therapeutic conclusions from Hcys alone 74 Testing Issues Standard Serum B12 and FBC Testing: Standard hemotological signs of B12 deficiency can be masked by synthetic folic acid fortification/supplementation Direct serum Vitamin B12 measurements notoriously unreliable (poor approximation and does not show functional need) 2014 distinguishing subjects with normal and cobalamin deficient conditions by a threshold level of serum B12 concentrations is unreliable and clinically misleading 75 25

31 Where To From There? 76 Gene Testing? 77 The Promise Of Genetics Human Genome sequence first announced in 2003! Has given researchers a greater understanding of human health Genomic information will allow early and more accurate prediction and diagnosis of disease and of disease progression. Medicine will become oriented towards disease prevention rather than efforts to cure people at late stages of illness John Bell Parallel to this growth will be impressive progress in understanding the specific influence of certain food components on metabolic pathways and on long term risk for disease (DeBusk, et al. 2005) 78 26

32 50% from Mum + 50% from Dad 79 Genetics 101 DNA Deoxyribonucleic acid (DNA) = hereditary blueprint Most located in the cell Nucleus (ndna) bundled as chromosomes (25,000+ genes) Consists of two complementary sides forming a helical ladder Small amount of DNA also found in the Mitochondria (mtdna) (37 genes) Chromosomes Microscopic finger like bundles of tightly wound DNA Humans normally contain 23 pairs of chromosomes in each cell (46 total mother & father donate half each pair) Replication Takes place when cells divide DNA copies itself so new cell contains same DNA as old cell

33 You are only 0.1% unique (we are all 99.9% identical) 82 x

34 Bases DNA code uses four chemical bases : Adenine (A) Guanine (G) Cytosine (C) Thymine (T) Base Pairs Two bases from each side of the strand join to make a unit: A always pairs with a T (and vice versa) C always pairs with a G (and vice versa) 85 Nucleotides Nucleotides incorporate bases Assemble to form two long strands Each strand comprises half of the double helix ladder Base Nucleotide 86 Genes Sections of DNA Serve as instructions and templates for making proteins Can vary in length from hundreds to millions of bases Two copies of each gene are inherited from each parent Genotype The TOTAL gene configuration an organism possesses Individualised by the different alleles inherited (one from each parent) at each gene location 87 29

35 GENE X T A C T C G Protein X Could be An Enzyme A Receptor A Hormone etc * Conformational shape determines function 88 For every enzyme there is a gene responsible for producing it 89 SNP (Single Nucleotide Polymorphism) A difference in one Base Pair at a single Nucleotide location (either in one or both connecting bases) Different from the norm, but NOT considered a mutation Occur on average once in every 300 nucleotides (very common) Can predispose a physical trait, attribute or physiological / metabolic behaviour (subtly changes how we function) Alleles Allelomorph means 'other form Refers to the DNA configuration at matching positions of a chromosome pair (Referenced against all known configurations) May include one or more SNPs (even whole genes) 90 30

36 For every enzyme there is a gene responsible for producing it 89

37 91 Mutations vs Variations Gene MUTATIONS Gene VARIATIONS High Penetrance Low Penetrance Involve large portions of Chromosomes Usually minor impact (do not usually Typically have major impact characterise Dx directly themselves) (often cause disease / easily noticeable) Therefore COMMON ARE passed on Therefore RARE NOT passed on Do however convey susceptibility to disease (risk) e.g. SNPs Predominantly 92 SNPs Contribute To Biochemical Individuality Different needs Different responses to clinical interventions Different paths to optimum wellbeing 93 31

38 The Impact? 94 Variations / Both gene copies are typical /+ One gene copy has the SNP +/+ Both copies have the SNP

39 The Degree Of Impact No alteration (most common configuration of a gene) An alteration in one side (heterozygous) means there is a backup gene that can fulfil SOME of the normal metabolic role/function An alteration on BOTH sides (homozygotes) usually has an even stronger impact on overall body metabolism (as there is no conventional code to fulfil the more typical function of that gene in compensation) BUT NOT ALWAYS A NEGATIVE AFFECT! 97 Understanding SNPs 3 billion base pairs We are only 0.1% different Still leaves a vast amount of differing SNPs! (~3 5 million inherited 30 new) May be multiple places in a gene where a single base is altered (multiple SNPs) How do we choose the single base changes (SNPs) that are most clinically relevant? RESEARCH! (To form valid Inclusion Criteria) 98 Proposed Criteria Before asnp Is Included in Clinical Analysis 1. Relevance SNP exerts a direct influence on specific biochemical processes that create known symptoms or disease 2. Prevalence Relatively common in the general population 3. Modifiability Expression of SNP is modifiable by known nutrition, environment or lifestyle interventions 4. Measurability Impact of clinical interventions on SNP expression is measureable by lab biochemistry 99 33

40 To Be Continued for