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Thiamine Biochemistry in Ethanol Consumption

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Thiamine Biochemistry in Ethanol Consumption Thiamine Biochemistry in Ethanol Consumption Thiamine Biochemistry in Ethanol Consumption ................................................................1 1. Biology of Substance ....................................................................................................6 1.1. Forms of thiamine.................................................................................................7 1.1.1. Different Supplemental Forms of Thiamine ..................................................8 1.2. Requirement for Thiamine..................................................................................10 1.2.1. Therapeutic Dose of Thiamine.....................................................................11 1.2.2. Toxic Doasage of Thiamine..........................................................................11 1.3. Thiamine Antagonists..........................................................................................12 1.3.1. Sulfites .........................................................................................................13 1.3.1.1. Sulfites cause thiamine deficiency .......................................................16 1.3.1.2. Sulfites and sulfur dioxide toxicity linked to heart failure ...................16 1.3.1.3. Sulfites in food and drinks contribute to cardiac disfunction..............17 1.3.1.4. The high sensitivity of thiamine to sulfites ..........................................17 1.3.1.5. Thiamine deficiencies caused by sulfite preservatives animal study ..17 1.3.1.6. Sulfites destroy thiamine in preventing browning of parboiled rice ...21 1.3.1.7. Sulfites in Alcoholic Beverages.............................................................21 1.3.1.8. The Molybdenum Biology of Sulfite Oxidase .......................................22 1.3.1.8.1. Sulfite Oxidase: Molybdenum enzyme converts Sulfite to Sulfate 26 1.3.2. Caffeic Acid and Polyphenols.......................................................................27 1.3.3. Losses in Food Preparation..........................................................................29 1.4. Experimental Models of Thiamine Deficit .........................................................31 1.5. Thiamine in Enzymic Reactions .........................................................................33 2. Deficiency...................................................................................................................37 2.1. Diagnosis and Identification Problems ..............................................................39 2.2. Thiamine Deficiency in Alcoholic Population ....................................................42 2.2.1. Liver Storage of Thiamine............................................................................42 2.3. Comorbidity of vitamin deficits .........................................................................43 2.4. Beri Beri .............................................................................................................43 2.4.1. Clinical Vignette for Wernicke's thiamine deficiency..................................44 2.5. Subclinical Thiamine Defciencies.......................................................................45 2.6. Elderly Predisposition to Thiamine Deficiency ..................................................47 2.7. Variations in causes of thiamine deficiency ......................................................49 2.7.1. Thiamine Transporter Proteins and Biotin ..................................................49 2.8. Gastrointestinal Problems .................................................................................50 3. Carbohydrate Metabolism.........................................................................................50 3.1. Carbohydrate loading produces similar polyneuropathys to Wernicke's/Korsakoff's psychosis..................................................................................51 3.2. Thiamine in Diabetic Advanced Glycation Endproducts ...................................51 3.3. Thiamine and dextrose in management of the comatose patient....................52 3.4. Emergency Treatment and Coma......................................................................52 4. Alcohol Consumption ................................................................................................53 1 4.1. Pharmacology of Ethanol...................................................................................58 4.2. Thiamine Deficiency as a predisopostion to and consequence of alcohol consumption ..................................................................................................................68 4.3. Alcohol Intoxication ...........................................................................................69 4.4. Thiamine Deficiency as a result of Alcoholism leading to Wernicke-Korsakoff Disease...........................................................................................................................72 4.5. Memory Dysfunction in Alcohol Intoxication....................................................73 4.6. Alcoholic Cerebellar Degeneration....................................................................74 4.6.1. Cerebellar Sensitivity to Lesions in Thiamine Deficit...................................76 4.7. Alcohol Induced Neuropathies ..........................................................................76 4.7.1. Thiamine and vitamin related neuropathies associated with ethanol and tabacco 77 4.8. Management of Alcohol Withdrawal ................................................................77 4.8.1. Thiamine treatment in alcoholism ..............................................................80 4.9. Fetal Alcohol Syndrome.....................................................................................81 4.9.1. Increased natal requirement for thiamine ..................................................81 4.9.2. The effect of ethanol on fetal development ...............................................82 5. Neural and Psychiatric Symptoms .............................................................................83 5.1. Depression like symptoms in thiamine deficiency ............................................83 5.2. Complex patterns of dementia in thiamine and vitamin deficiency .................84 5.3. Thiamine and Alzheimer's Disease ....................................................................84 5.4. Psychiatric disorder resulting from Thiamine Deficit ........................................86 5.5. Wernickes Encephalopathy ...............................................................................87 5.5.1. Memory Dysfunction in Wernicke's Encephalopathy .................................90 5.5.2. Wernicke's physiology similar to Alzheimer's .............................................90 5.5.3. Glutamate neurotoxicity (or excitotoxicity) is the primary cause of the Thiamine Deficiency Encephalopathy .......................................................................91 5.5.4. Age-related differences in the areas of Broca and Wernicke .....................91 5.5.5. Damage to Wernicke's area linked to thiamine deficit and memory damage 92 5.5.6. Clinical Features of Wernicke's leading to Korsakoff's................................92 5.5.7. Glutamate Excitotoxcity Suggested as Causing Wernicke's Lesions ...........93 5.6. Korsakoff Syndrome ..........................................................................................94 5.6.1. Memory Dysfunction in Alcoholic Korsakoff Syndrome..............................94 5.6.2. Anterograde amnesia in Korsakoff's syndrome ..........................................95 5.6.3. Memory, Amnesia and Thiamine Deficiency...............................................95 5.7. Wernicke-Korsakoff's is the third most common dementia .............................99 6. Neurotransmission ..................................................................................................100 6.1. Thiamine deficit impairs cholinergic functioning ............................................100 6.1.1. Acetyl Choline linked with Alzheimer's Disease ........................................100 6.1.2. Thiamine deficiency and the loss of cholinergic cells................................101 6.1.3. Cholinergic neurons co-release other neurotransmitters such as GABA and glutamate.................................................................................................................101 6.1.4. Thiamine and Acetyl Choline Functioning .................................................102 2 6.2. Demyelination in Thiamine Deficiency............................................................102 6.3. Thiamine functioning in the nervous system ..................................................103 6.4. Thiamine in Neurotransmitter Metabolism ....................................................103 7. Cardiovascular Disease ............................................................................................103 7.1. Thiamine deficiency is defined by heart disease.............................................104 7.2. Thiamine deficiency common in heart failure patients ..................................104 7.3. Thiamine supplementation improves forms of heart failure..........................105 7.4. Thiamine triphosphate postulated as important for heart contraction .........105 7.5. Pathologically High Cardiac Output in thiamine deficiency ............................105 7.6. Systemic Vascular Resistance, Heart Failure and Thiamine ............................107
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