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Epigenetic Effects In Substance Abuse => Chromatin Therapeutics

Epigenetic Effects In Substance Abuse => Chromatin Therapeutics. Alexander J Annala, PhD Newton Clinical Research Group UCLA ISAPI NPI&H. Motivation.

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Epigenetic Effects In Substance Abuse => Chromatin Therapeutics

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  1. Epigenetic Effects InSubstance Abuse=>Chromatin Therapeutics

  2. Alexander J Annala, PhDNewton Clinical Research GroupUCLA ISAPI NPI&H

  3. Motivation Setting Priorities for Basic Brain & Behavioral Science at NIMH Final Report of the National Advisory Mental Health Council’s Workgroup on Basic Sciences – 5/2004 – Page 4 "This emerging field of epigenetics has received relatively little attention at NIH, as the tools for analysis of such interaction have not yet been solidified. The Workgroup considers it time to invest more in developing the tools that will allow intensive study in this area, given that most mental disorders appear to involve or result from such dynamic processes over time.“

  4. Speculative Discussion While The Evidence Is Not Rock Solid – There Is Sufficient Information Available To Recommend Increased Attention To Potential Epigenetic Effects In Substance Abuse Speculative – Per Oxford English Dictionary 2nd Edition Of the nature of, based upon, characterized by, speculation or theory in contrast to practical or positive knowledge

  5. Classical Genetics DNA => RNA => PROTEIN The Central Dogma

  6. Human Genome Project Describe Shared Human DNA Map Search For DNA Mutations Permanent A C T G Base Changes Insertions, Deletions & Substitutions => Disease & Pathological Conditions

  7. DNA Mutations Can Be Measured By Many Methods Polymerase Chain Reaction (PCR) DNA Gene Chip Analysis

  8. DNA Mutations Can Lead To Ablation of Common Genes or Addition of Novel Genes or Changes In Protein Product Structure

  9. DNA Mutations Changes Are Generally Reflected In Every Cell Throughout The Body When Mutation Occurs In A Germ Cell or In One Specific Cell Line When Mutation Occurs In A Somatic Cell

  10. Differentiation & Development Do Not Involve DNA Mutation Do Involve Changes In Gene Expression Changes Restricted To Specific Cell Lineage

  11. Differentiation & Development Pancreatic Islet Cells and Hepatocytes Are Derived From A Common Progenitor Cell Line – But Differ From Each Other By Means Of Long Lasting Changes In Silencing Or Expression Of Specific Genes HNF-4 Expression => Hepatocyte-Like Cells

  12. Changes In Gene Expression Can Be Measured By Many Means RNA Reverse Transcriptase PCR RNA Gene Chip Analysis

  13. Principal Epigenetic Phenomena DNA Cytosine-5 Methylation and / or Histone H3 & H4 Tail Acetylation

  14. Epigenetic Phenomena Control Dynamic Changes In Gene Expression Not Based on Permanent DNA Mutation

  15. Epigenetic Phenomena While Epigenetic Changes In Gene Expression Are Not Permanent They Can Be Long Lasting

  16. Routine Epigenetic Changes DNA Methylation + Histone Tail Acetylation Changes In Early Childhood Silence Fetal Hemoglobin Gene Expression Activate Adult Hemoglobin Gene Expression These Changes Last An Entire Lifetime

  17. Pathologic Epigenetic Changes DNA Methylation + Histone Acetylation In Fragile X Mental Retardation Silences FMR-1 These Changes Last An Entire Lifetime

  18. Epigenetic Phenomena DNA Methylation Changes & Histone Modifications => Remodeling of Chromatin

  19. DNA Methylation Changes Cytosine-5 Methylation By DNA Methyltransferase (DNMT) cggcggcggcggcggcggcggc => m m m m m m m m cggcggcggcggcggcggcggc

  20. DNA Methylation Interferes With Formation of Transcription Factor Complex (DNA => RNA Initiation)

  21. DNA Methylation Interfers With Transcription Of DNA Into RNA By Retarding The Progress Of DNA => RNA Transcriptase Reducing Amount of Protein Product (DNA => RNA Precession)

  22. DNA Methyltransferase Inhibitors (DNMTi) 5-aza-cytidine 5-aza-2-deoxycytidine MG98 [Methylgene Inc] Zebularine [Eric Selker, U Oregon]) => Orally Bioavailable Nontoxic

  23. Zebularine (DNMTi) NIH / NIGMS FY 2005 Budget Page 12 Eric Selker, PhD demonstrated Zebularine PO reverses DNA methylation and reactivates a tumor suppressor gene in human bladder cancer injected into mice. Zebularine reduced tumor size in the mice, making zebularine the first DNA methylation inhibitor to have such an effect in animals. Zebularine is unique among the DNA methylation inhibitors that have been studied to date because it is chemically stable, can be administered orally, and appears to be minimally toxic. Its only side effect seems to be a slight weight loss in the mice given the chemical.

  24. Zebularine (DNMTi) J Natl Cancer Inst. 2003 Mar 5;95(5):399-409

  25. Chromatin The Combination Of DNA Base Pairs ( A C T G ), DNA Structure (Coils, Supercoils) And DNA Packaging Materials

  26. Chromatin May Be Conceptually Visualized As A Long Strand Of DNA (A C T G) Which May Be Marked (C5-Methylated) and / or Which May Be Wound Around A Long Series of Tiny Spools (Histones)

  27. Chromatin May Take One Of Two Primary Forms Euchromatin (Active/Expressed) or Heterochromatin (Repressed/Silent)

  28. Histone H3/H4 Tail Acetylation Histone Tail Acetylation Is Controlled By Dynamic Balance Between Enzyme Activities Histone Acetyl Transferase (HAT) and Histone Deacetylase (HDAC)

  29. Histone H3/H4 Tail Acetylation Histones H3 and H4 May Be Conceptually Visualized As A Long Series Of Tiny Spools Around Which Short Segments Of One Long Strand Of DNA May Be Wound

  30. Histone H3/H4 Tail Acetylation Histones H3 and H4 Have Tails Which May Be Conceptually Visualized As Four Short Protein Strands Extending Away From Each Histone Spool

  31. Histone H3/H4 Tail Acetylation H3/H4 Tail Acetylation Stiffens Each Tail Increasing Space Occupied By Each Histone Spool H3/H4 Tail DeAcetylation Relaxes Each Tail Compacting Space Occupied By Each Histone Spool

  32. Chromatin Increased Acetylation of H3/H4 Tails Forms Euchromatin Stiffer Tails Make It Difficult For DNA To Be Tightly Compacted Leaving DNA Readily Accessible To Initiation and Precession of DNA=>RNA Transcription Machinery => Increased Gene Expression

  33. Chromatin Decreased Acetylation of H3/H4 Tails Forms Heterochromatin Flexible Tails Make It Easy For DNA To Be Tightly Compacted Making DNA Less Accessible To Initiation and Precession of DNA=>RNA Transcription Machinery => Decreased Gene Expression

  34. Chromatin Increased Acetylation of H3/H4 Tails => Euchromatin => Increased Gene Expression Decreased Acetylation of H3/H4 Tails => Heterochromatin => Decreased Gene Expression

  35. Histone Deacetylase Inhibitors (HDACi) Trichostatin A (TSA) Valproic Acid (Depakote, Depakene) Butyrate (ArgBu, NaBu, BA, 4-PBA) SAHA, CHR-2504 [Chroma Therapeutics], and MGCD0103 [Methylgene Inc])

  36. Sickle Cell Anemia Symptoms Of Sickle Cell Anemia, B-Thalassemia & Similar Conditions May Be Relieved By Reactivation Of Fetal Hemoglobin Expression Using Histone Deacetylase Inhibitor Arginine-Butyrate (HDACi)

  37. Sickle Cell + HDACi N Engl J Med. 1993 Jan 14;328(2):81-6

  38. Fragile X Mental Retardation FRAXA Is Usually Characterized By DOUBLE LOCK On FMR-1 Gene Expression Due To DNA Methylation And Histone Deacetylation

  39. Fragile X => DOUBLE LOCK DNA Methylation + Histone Deacetylation => Heterochromatin Hum Mol Genet. 1999 Nov;8(12):2317-23

  40. Fragile X Mental Retardation FRAXA May Ultimately Be Treated By Either HDACi Or DNMTi Alone Or By HDACi + DNMTi Combination HDACi + DNMTi => Synergy

  41. Fragile X + HDACi Hum Mol Genet. 1999 Nov;8(12):2317-23

  42. Fragile X + HDACi Hum Mol Genet. 1999 Nov;8(12):2317-23

  43. Fragile X + DNMTi Hum Mol Genet. 1999 Nov;8(12):2317-23

  44. Fragile X + HDACi +DNMTi Synergism 0.2 or 1.0 uM 5azaDC + 5um BA or 4-PBA (Open = 5-azaDC Black=5azaDC +(BA or 4-PBA) Hum Mol Genet. 1999 Nov;8(12):2317-23

  45. Histone Code Hypothesis Histone H3 Methylated At Lysine 9 => Heterochromatin (Silent/Repressed) Histone H3 Methylated At Lysine 4 => Euchromatin (Expressed/Active)

  46. Histone Code Hypothesis There Are Numerous Additional Histone Modifications Leading To Specific Activational Effects However H3-K4 / H3-K9 Are The Most Comprehensively Characterized Modifications Identified To Date

  47. Ethanol Addiction SAMe Improves Performance of Alcoholics On Psychometric Tests Vittorio Coiro & Pier Paolo Vescovi Controlled Study of Psychometric Performance In Abstinent Alcoholics: Masked Comparison Of The Effects Of 15 Day Intravenous Treatments With S-Adenosylmethionine Or Normal Saline Current Therapeutic Research 58(9):575-586 (1997)

  48. Ethanol Addiction ETOH Demethylates NMDA-NR2B Promoter => Upregulating NR2B Expression C R Marutha Ravindran & Maharaj K Ticku Changes In Methylation Pattern Of NMDA Receptor NR2B Gene In Cortical Neurons After Chronic Ethanol Treatment In Mice Molecular Brain Research 121:19-17 (2004)

  49. Ethanol Addiction Pre-Conception Sire Exposure To EOTH => Degrades Mouse Pup Maze & Reflex Performance Patricia A Jamerson, Michael J Wulser, Bruce F Kimler Neurobehavioral Effects In Rat Pups Whose Sires Were Exposed To Alcohol Developmental Brain Research 149:103-111 (2004)

  50. Ethanol Addiction Hepatocyte H3K9 Acetylated 8-10X By 5mM ETOH Phil-Hoon Park, Rebecca Miller & Shivendra D Shukla Acetylation Of Histone H3 At Lysine 9 By Ethanol In Rat Hepatocytes Biochemical & Biophysical Research Communications 306:501-594 (2003)

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