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1.
Cells ; 10(10)2021 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-34685573

RESUMEN

Thiamine or vitamin B1 is an essential, water-soluble vitamin required for mitochondrial energetics-the production of adenosine triphosphate (ATP). It is a critical and rate-limiting cofactor to multiple enzymes involved in this process, including those at the entry points and at critical junctures for the glucose, fatty acid, and amino acid pathways. It has a very short half-life, limited storage capacity, and is susceptible to degradation and depletion by a number of products that epitomize modern life, including environmental and pharmaceutical chemicals. The RDA for thiamine is 1.1-1.2 mg for adult females and males, respectively. With an average diet, even a poor one, it is not difficult to meet that daily requirement, and yet, measurable thiamine deficiency has been observed across multiple patient populations with incidence rates ranging from 20% to over 90% depending upon the study. This suggests that the RDA requirement may be insufficient to meet the demands of modern living. Inasmuch as thiamine deficiency syndromes pose great risk of chronic morbidity, and if left untreated, mortality, a more comprehensive understanding thiamine chemistry, relative to energy production, modern living, and disease, may prove useful.


Asunto(s)
Deficiencia de Tiamina/diagnóstico , Femenino , Humanos , Masculino
2.
Med Hypotheses ; 129: 109252, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31371089

RESUMEN

A huge number of proteins that occur in the body have to be folded into a specific shape in order to become functional. Proteins are made up of chains of amino acids and the folding process is exquisitely complex. When this folding process is inhibited, the respective protein is referred to as being misfolded and nonfunctional. So the hypothesis that follows is in regard to the diseases that are caused by the misfolding of vital proteins and their reported relationship with thiamin metabolism. These diseases are termed proteopathies and there are at least 50 different conditions in which the mechanism is importantly related to a misfolded protein. In the brain, thiamin deficiency causes a cascade of events involving mild impairment of oxidative metabolism, neuroinflammation and neurodegeneration, including the pathology of Alzheimer's disease, Parkinson's and Huntington's diseases, all of which are examples of proteopathies. Prion diseases are fatal neurodegenerative disorders related to the conformational alteration of the prion protein (PrP C) into a pathogenic and protease-resistant isoform (PrPSc). The physiological form (PrP C) is a cell surface glycoprotein expressed mainly in the central nervous system. Despite numerous efforts to elucidate its role, the exact biological function remains unknown. Prion-induced diseases, due to the conformational change in the protein, are a global health problem, with lack of effective therapy and 100% mortality. Thiamin and its derivatives bind the prion protein and intermolecular actions have been noted between thiamin and other thiamin-binding proteins, although the exact importance of this is conjectural.


Asunto(s)
Pliegue de Proteína , Tiamina/fisiología , Animales , Encéfalo/metabolismo , Predisposición Genética a la Enfermedad , Glicoproteínas/química , Humanos , Inflamación , Modelos Teóricos , Mutación , Proteínas PrPSc/química , Proteínas Priónicas/metabolismo , Unión Proteica , Conformación Proteica , Tiamina/química , Deficiencia de Tiamina , alfa 1-Antitripsina/química , alfa 1-Antitripsina/genética
3.
Adv Food Nutr Res ; 83: 1-56, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29477220

RESUMEN

Starting with a brief history of beriberi and the discovery that thiamin deficiency is its cause, the symptoms and signs are reviewed. None are pathognomonic. The disease has a low mortality and a long morbidity. The appearance of the patient can be deceptive, often being mistaken for psychosomatic disease in the early stages. The chemistry of thiamin and the laboratory methodology for depicting its deficiency are outlined. The diseases associated with thiamin deficiency, apart from malnutrition, include a number of genetically determined conditions where mutations, either in the cofactor relationship or a transporter, provide the etiology. It is emphasized that such mutations are often epigenetically responsive to megadoses of thiamin or one of its derivatives. The use of thiamin in clinical practice requires a high index of suspicion on the part of the clinician since it has a part to play in eating disorders, diabetes, neurodegenerative disease, and cancer. A high rate of critical illness and postsurgery thiamin deficiency have been reported, particularly those associated with gastrointestinal bypass. Emphasis is placed on thiamin deficiency as a major cause of asymmetric dysautonomia, because of the high degree of sensitivity to thiamin deficiency in the brainstem, cerebellum, and hypothalamus. The relationship of thiamin with regional pain syndrome, eosinophilic esophagitis, its analgesic capacity, and its preventive use in obstetrics is raised as a potential issue. The role of thiamin in SIDS and autism is outlined. It is emphasized that megadose thiamin is being used as a drug, either in stimulating the damaged cofactor/enzyme combination, or mitochondria.


Asunto(s)
Deficiencia de Tiamina/prevención & control , Tiamina/administración & dosificación , Tiamina/farmacología , Dieta , Predisposición Genética a la Enfermedad , Humanos , Estrés Fisiológico , Deficiencia de Tiamina/epidemiología , Deficiencia de Tiamina/etiología , Deficiencia de Tiamina/genética , Vitaminas/administración & dosificación , Vitaminas/farmacología
4.
Med Hypotheses ; 85(6): 922-6, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26455416

RESUMEN

Although it has been generally accepted that moving the infant from the prone to the supine position has solved the problem of sudden infant death syndrome (SIDS), it has been hypothesized that this is an insufficient explanation and that a mixture of genetic risk, some form of stressful incident and marginal brain metabolism is proportionately required. It is suggested that each of these three variables, with dominance in one or more of them, act together in the common etiology. Much has been written about the association of thiamin and magnesium but the finding of extremely high concentrations of serum thiamin in SIDs victims has largely caused rejection of thiamin as being involved in the etiology. The publication of abnormal brainstem auditory evoked potentials strongly suggests that there are electrochemical changes in the brainstem affecting the mechanisms of automatic breathing and the control of cardiac rhythm. The brainstem, cerebellum and limbic system of the brain are known to be highly sensitive to thiamin deficiency (pseudo-hypoxia) and the pathophysiology is similar to a mild continued deprivation of oxygen. Little attention has been paid to the complex metabolism of thiamin. Dietary thiamin requires the cooperation of the SLC19 family of thiamin transporters for its absorption into cells and recent information has shown that transporter SNPs may be relatively common and can be expected to increase genetic risk. Thiamin must be phosphorylated to synthesize thiamin pyrophosphate (TPP), well established in its vital action in glucose metabolism. TPP is also a cofactor for the enzyme 2-hydroxyacyl-CoA lyase (HACL1) in the peroxisome, emphasizing its importance in alpha oxidation and plasmalogen synthesis in cell membrane physiology. The importance of thiamine triphosphate (TTP) in energy metabolism is still largely unknown. Thiamin metabolism has been implicated in hyperemesis gravidarum and iatrogenic Wernicke encephalopathy has been reported when the patient is treated with hyperalimentation, in spite of the pharmaceutical doses of thiamin in the intravenous fluid. Defective glucose metabolism, the vital fuel for energy synthesis, particularly in brain, must affect the developing fetus and the pattern of subsequent neonatal health. Sudden death in an apparently healthy infant, occurring at 3-4months, has long been known to result from feeding the infant with thiamin deficient breast milk. The early investigators of the cause of beriberi considered that this form of sudden death was pathognomonic of the infantile form of the disease.


Asunto(s)
Muerte Súbita del Lactante , Tiamina/metabolismo , Adolescente , Tronco Encefálico/fisiopatología , Liasas de Carbono-Carbono , Membrana Celular/metabolismo , Enoil-CoA Hidratasa/metabolismo , Potenciales Evocados Auditivos , Genómica , Glucosa/metabolismo , Humanos , Hipoxia , Lactante , Síndrome de Taquicardia Postural Ortostática/fisiopatología , Disautonomías Primarias/fisiopatología , Estrés Psicológico , Tiamina/sangre , Deficiencia de Tiamina/fisiopatología , Tiamina Pirofosfato/metabolismo , Vacunación
5.
Front Biosci (Elite Ed) ; 7(2): 229-41, 2015 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-25553376

RESUMEN

Although there has been much research into autism or autistic spectrum disorder (ASD), there is room for considerable conjecture regarding the etiology of these developmental brain disorders. ASD is marked by a complex interaction between environmental factors and genetic predisposition, including epistasis. This manuscript argues that changes in oxidative metabolism, thiamine homeostasis, heavy metal deposition and cellular immunity have a role in the etiopathogenesis of autism and ASD. Recent findings from our group and others provide evidence for abnormal thiol metabolism, marked by significant alteration in the deposition of several trace heavy metal species. Together with these, we find differences in thiamine homeostasis in ASD patients, which can be corrected by supplementation. We hypothesize that altered thiol metabolism from heavy metal toxicity, one of the key mechanisms for oxidative stress production, may be responsible for the biochemical alterations in transketolase, dysautonomia and abnormal thiamine homeostasis. Although it is unknown why these particular metals accumulate, we suspect that children with ASD and forms of autism may have particular trouble excreting thiol-toxic heavy metal species, many of which exist as divalent cations. We maintain mercury accumulation is evidence of altered clearance. Together with concomitant oxidative stress, these findings may offer an intriguing component or possible mechanism for oxidative stress-mediated neurodegeneration in ASD patients. Regardless of the exact cause, these factors may be more important to the etiology of this symptomatically diverse disease spectrum. Here, we offer insight into new avenues of exploration as well as the development of novel treatment approaches for these growing and devastating diseases.


Asunto(s)
Trastornos Generalizados del Desarrollo Infantil/etiología , Trastornos Generalizados del Desarrollo Infantil/metabolismo , Tiamina/metabolismo , Transcetolasa/metabolismo , Trastornos Generalizados del Desarrollo Infantil/tratamiento farmacológico , Homeostasis , Humanos , Mutación , Estrés Oxidativo , Tiamina/análogos & derivados , Tiamina/uso terapéutico
6.
Subcell Biochem ; 56: 199-227, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22116701

RESUMEN

One of the earliest vitamins to be discovered and synthesized, thiamin was originally spelled with an "e". The terminal "e" was dropped when it was found that it was not an amine. It is still spelled with and without the "e" depending on the text. This chapter provides a brief historical review of the association of thiamin with the ancient scourge of beriberi. It emphasizes that beriberi is the model for high calorie malnutrition because of its occurrence in predominantly white rice consuming cultures. Some of the symptomatology of this ancient scourge is described, emphasizing the difference from that seen in starvation. High calorie malnutrition, due to excessive ingestion of simple carbohydrates, is widely encountered in the U.S.A. today. Thiamin deficiency is commonly associated with this, largely because of its cofactor status in the metabolism of glucose. The biochemistry of the three phosphorylated esters of thiamin and the transporters are discussed and the pathophysiology of thiamin deficiency reviewed. The role of thiamin, and particularly its synthetic derivatives as therapeutic agents, is not fully appreciated in Western civilization and a clinical section describes some of the unusual cases described in the scientific literature and some experienced by the author. The possible role of high calorie malnutrition and related thiamin deficiency in juvenile crime is hypothesized.


Asunto(s)
Tiamina/fisiología , Animales , Beriberi/epidemiología , Beriberi/etiología , Beriberi/historia , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Proteínas de Transporte de Membrana/metabolismo , Tiamina/análogos & derivados , Tiamina/uso terapéutico , Deficiencia de Tiamina/complicaciones , Deficiencia de Tiamina/epidemiología , Deficiencia de Tiamina/historia , Deficiencia de Tiamina/terapia , Tiamina Trifosfato/fisiología
7.
Biol Trace Elem Res ; 144(1-3): 475-86, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21755304

RESUMEN

Autism and autism spectrum disorder (ASD) are developmental brain disorders with complex, obscure, and multifactorial etiology. Our recent clinical survey of patient records from ASD children under the age of 6 years and their age-matched controls revealed evidence of abnormal markers of thiol metabolism, as well as a significant alteration in deposition of several heavy metal species, particularly arsenic, mercury, copper, and iron in hair samples between the groups. Altered thiol metabolism from heavy metal toxicity may be responsible for the biochemical alterations in transketolase, and are mechanisms for oxidative stress production, dysautonomia, and abnormal thiamine homeostasis. It is unknown why the particular metals accumulate, but we suspect that children with ASD may have particular trouble excreting thiol-toxic heavy metal species, many of which exist as divalent cations. Accumulation or altered mercury clearance, as well as concomitant oxidative stress, arising from redox-active metal and arsenic toxicity, offers an intriguing component or possible mechanism for oxidative stress-mediated neurodegeneration in ASD patients. Taken together, these factors may be more important to the etiology of this symptomatically diverse disease spectrum and may offer insights into new treatment approaches and avenues of exploration for this devastating and growing disease.


Asunto(s)
Trastorno Autístico/metabolismo , Metales Pesados/metabolismo , Transcetolasa/metabolismo , Trastorno Autístico/enzimología , Niño , Eritrocitos/enzimología , Femenino , Cabello/química , Humanos , Indicadores y Reactivos , Masculino , Espectrometría de Masas , Metales Pesados/orina , Estrés Oxidativo/fisiología , Tiamina Pirofosfato , Transcetolasa/sangre
8.
Autism Res Treat ; 2011: 129795, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22937241

RESUMEN

Case histories of a mother and her two children are reported. The mother was a recovered alcoholic. She and her two children, both of whom had symptoms that are typical of autistic spectrum disorder, had dysautonomia. All had intermittently abnormal erythrocyte transketolase studies indicating abnormal thiamine pyrophosphate homeostasis. Both children had unusual concentrations of urinary arsenic. All had symptomatic improvement with diet restriction and supplementary vitamin therapy but quickly relapsed after ingestion of sugar, milk, or wheat. The stress of a heavy metal burden, superimposed on existing genetic or epigenetic risk factors, may be important in the etiology of autism spectrum disorder when in combination. Dysautonomia has been associated with several diseases, including autism, without a common etiology. It is hypothesized that oxidative stress results in loss of cellular energy and causes retardation of hard wiring of the brain in infancy, affecting limbic system control of the autonomic nervous system.

9.
Evid Based Complement Alternat Med ; 6(1): 3-10, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18955227

RESUMEN

Dysautonomia refers to a disease where the autonomic nervous system is dysfunctional. This may be a central control mechanism, as in genetically determined familial dysautonomia (Riley-Day Syndrome), or peripherally in the distribution of the sympathetic and parasympathetic systems. There are multiple reports of a number of different diseases associated with dysautonomia. The etiology of this association has never been explained. There are also multiple publications on dysautonomia associated with specific non-caloric nutritional deficiencies. Beriberi is the prototype of autonomic dysfunction. It is the best known nutritional deficiency disease caused by an imbalance between ingested calories and the vitamins required for their oxidation, particularly thiamin. Long thought to be abolished in modern medical thinking, there are occasional isolated reports of the full-blown disease in developed Western cultures. Apart from genetically and epigenetically determined disease, evidence is presented that marginal high calorie malnutrition, particularly with reference to simple carbohydrates, is responsible for widespread dysautonomia. The brain and heart are the organs that have a fast rate of oxidative metabolism and are affected early by any mechanism that reduces oxidative efficiency. It is hypothesized that this results in a chaotic state of the hypothalamic/autonomic/endocrine axis. Due to the lack of adequate automatic controls, this may be responsible in some cases for breakdown of organ systems through long-standing energy deficiency, thus leading eventually to organic disease.

10.
Evid Based Complement Alternat Med ; 4(2): 247-50, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17549243

RESUMEN

Non-caloric nutrients (NCN) are extremely numerous and it is more than obvious that they work in a team relationship. These vitally important interactions are, for the most part, poorly understood. These brief case reports illustrate this in the therapeutic use of thiamin in a clinical setting. The initially abnormal erythrocyte transketolase activity (TKA) and/or the thiamin pyrophosphate effect (TPPE), indicating intracellular cofactor deficiency, usually improves with thiamin administration. Biochemical correction of the abnormality is, however, invariably dependent on the provision of other NCN, especially magnesium. In two patients reported here, this correction required several infusions containing magnesium and other NCN administered intravenously. In a third patient, hemoconcentration associated with an abnormal TPPE was normalized after administration of nutrients that included thiamin and magnesium.

11.
Evid Based Complement Alternat Med ; 3(1): 49-59, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16550223

RESUMEN

Thiamin(e), also known as vitamin B1, is now known to play a fundamental role in energy metabolism. Its discovery followed from the original early research on the 'anti-beriberi factor' found in rice polishings. After its synthesis in 1936, it led to many years of research to find its action in treating beriberi, a lethal scourge known for thousands of years, particularly in cultures dependent on rice as a staple. This paper refers to the previously described symptomatology of beriberi, emphasizing that it differs from that in pure, experimentally induced thiamine deficiency in human subjects. Emphasis is placed on some of the more unusual manifestations of thiamine deficiency and its potential role in modern nutrition. Its biochemistry and pathophysiology are discussed and some of the less common conditions associated with thiamine deficiency are reviewed. An understanding of the role of thiamine in modern nutrition is crucial in the rapidly advancing knowledge applicable to Complementary Alternative Medicine. References are given that provide insight into the use of this vitamin in clinical conditions that are not usually associated with nutritional deficiency. The role of allithiamine and its synthetic derivatives is discussed. Thiamine plays a vital role in metabolism of glucose. Thus, emphasis is placed on the fact that ingestion of excessive simple carbohydrates automatically increases the need for this vitamin. This is referred to as high calorie malnutrition.

12.
Med Sci Monit ; 10(9): RA199-203, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15328496

RESUMEN

Thiamine tetrahydrofurfuryl disulfide (TTFD) is the synthetic counterpart of allithiamine, occurring naturally in garlic. Allithiamine was discovered in Japan in 1951. Its extensive research was reported by a group known as the Vitamin B Research Committee of Japan, and given this name because of its existence in the bulbs of many of the allium species of plants. It was found to be a disulfide derivative of thiamine, produced as a result of enzymatic action on the thiamine molecule in garlic bulbs when the bulb is cut or crushed. Subsequent experimental work in both animals and human subjects revealed that its metabolic effect was much more powerful than the thiamine from which it was derived. Japanese investigators created a number of synthetic forms and investigated their use in a number of human disease conditions. Although some derivatives have been synthesized without a disulfide bond in the molecule, these investigators emphasized that the disulfide was an extremely important part of its biologic action and TTFD is the most modern of the disulfide derivatives. Because at least part of its beneficial effects are the same as water soluble thiamine salts, this review deals first with the clinical uses of thiamine (vitamin B1) in medicine.


Asunto(s)
Fursultiamina , Tiamina/análogos & derivados , Disulfuros/metabolismo , Fursultiamina/química , Fursultiamina/metabolismo , Fursultiamina/uso terapéutico , Ajo/química , Humanos , Japón , Tiamina/química
13.
Neuro Endocrinol Lett ; 23(4): 303-8, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12195231

RESUMEN

OBJECTIVES: In a Pilot Study, the clinical and biochemical effects of thiamine tetrahydrofurfuryl disulfide (TTFD) on autistic spectrum children were investigated. SUBJECTS AND METHODS: Ten children were studied. Diagnosis was confirmed through the use of form E2, a computer assessed symptom score. For practical reasons, TTFD was administered twice daily for two months in the form of rectal suppositories, each containing 50 mg of TTFD. Symptomatic responses were determined through the use of the computer assessed Autism Treatment Evaluation Checklist (ATEC) forms. The erythrocyte transketolase (TKA) and thiamine pyrophosphate effect (TPPE), were measured at outset and on completion of the study to document intracellular thiamine deficiency. Urines from patients were examined at outset, after 30 days and after 60 days of treatment and the concentrations of SH-reactive metals, total protein, sulfate, sulfite, thiosulfate and thiocyanate were determined. The concentrations of metals in hair were also determined. RESULTS: At the beginning of the study thiamine deficiency was observed in 3 out of the 10 patients. Out of 10 patients, 6 had initial urine samples containing arsenic in greater concentration than healthy controls. Traces of mercury were seen in urines from all of these autistic children. Following administration of TTFD an increase in cadmium was seen in 2 children and in lead in one child. Nickel was increased in the urine of one patient during treatment. Sulfur metabolites in urine did not differ from those measured in healthy children. CONCLUSIONS: Thiamine tetrahydrofurfuryl disulfide appears to have a beneficial clinical effect on some autistic children, since 8 of the 10 children improved clinically. We obtained evidence of an association of this increasingly occurring disease with presence of urinary SH-reactive metals, arsenic in particular.


Asunto(s)
Trastorno Autístico/tratamiento farmacológico , Fursultiamina/administración & dosificación , Deficiencia de Tiamina/tratamiento farmacológico , Arsénico/análisis , Arsénico/orina , Trastorno Autístico/complicaciones , Niño , Preescolar , Femenino , Cabello/química , Humanos , Plomo/análisis , Plomo/orina , Masculino , Proyectos Piloto , Índice de Severidad de la Enfermedad , Deficiencia de Tiamina/complicaciones
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