Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Thiamine-responsive megaloblastic anemia with diabetes and deafness (TRMA) is an autosomal recessive disease caused by mutations in the high-affinity thiamine transporter gene SLC19A2. To study the role of thiamine transport in the pathophysiology of TRMA syndrome and of each of the component disorders, we created a targeted disruption of the Slc19a2 gene in mice. Slc19a2 -/- mice are viable and females are fertile. Male -/- mice on a pure 129/Sv background are infertile with small testes (testis/body weight=0.13 +/- 0.04 knockout vs. 0.35 +/- 0.05 wild type, P<0.000005). The lack of developing germ cells beyond primary spermatocytes suggests an arrest in spermatogenesis prior to meiosis II. Nuclear chromatin changes indicative of apoptosis are present. No mature sperm are found in the tubules or epididymis. This phenotype suggests a previously unknown role for thiamine transport in spermatogenesis and male fertility. Slc19a2 -/- mice on a pure 129/Sv background develop reticulocytopenia after two weeks on thiamine-depleted chow with a virtual absence of reticulocytes in the peripheral blood (0.12% knockout vs. 2.58% wild type, P=0.0079). Few erythroid precursors are found in the bone marrow. Contrary to human TRMA syndrome, we see no evidence of megaloblastosis or ringed sideroblasts in the bone marrow of Slc19a2 -/- mice in thiamine-replete or thiamine-deficient dietary states. Phenotypic differences between TRMA patients and Slc19a2 -/- mice might be explained by dissimilar tissue expression patterns of the transporter, as well as by differing metabolic needs and possible different species-specific contributions of the related thiamine transporter Slc19a3.
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PMID:Male infertility and thiamine-dependent erythroid hypoplasia in mice lacking thiamine transporter Slc19a2. 1456 73

Thiamine-responsive megaloblastic anemia (TRMA) syndrome is a rare autosomal recessive disorder defined by the occurrence of megaloblastic anemia, diabetes mellitus, and sensorineural deafness, responding in varying degrees to thiamine treatment. Other features of this syndrome gradually develop. We describe three TRMA patients with heart rhythm abnormalities and structural cardiac anomalies. Eight other reported TRMA patients also had cardiac anomalies. Recently, the TRMA gene, SLC19A2, was identified, encoding a functional thiamine transporter. Characterization of the metabolic defect of TRMA may shed light on the role of thiamine in common cardiac abnormalities.
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PMID:Cardiac manifestations in thiamine-responsive megaloblastic anemia syndrome. 1462 17

Thiamine-responsive megaloblastic anemia (TRMA) syndrome is an autosomal recessive disorder characterized by diabetes mellitus (DM), progressive sensorineural deafness, and thiamine-responsive anemia. Mutations in the SLC19A2 gene encoding a high-affinity thiamine transporter protein THTR-1 are responsible for the clinical features associated with TRMA syndrome. We report an African-American female with TRMA-syndrome associated with thyroid disease and retinitis pigmentosa caused by a novel mutation in the SLC19A2 gene. The patient presented at 12 months of age with paroxysmal atrial tachycardia and hepatosplenomegaly. One month later, she developed DM requiring intermittent insulin therapy. At 2-1/2 years of age, profound sensorineural hearing loss was discovered. By 4 years of age, daily insulin therapy (0.5 U/kg/day) was instituted and her insulin requirement gradually increased to 1.0 U/kg/day by 9 years of age. She developed optic atrophy, retinitis pigmentosa, and visual impairment by 12 years of age with severe restriction of peripheral vision by 16 years. At age 19, a thiamine-responsive normocytic anemia was discovered. She was diagnosed with autoimmune thyroiditis at 20 years and she experienced a psychotic episode associated with a mood disorder at age 21. With oral thiamine therapy, her insulin requirement decreased by 30% over a 20 month period. Molecular analysis revealed that the patient is homozygous for a missense mutation (C152T) in exon 1 of the SLC19A2 gene.
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PMID:Novel mutation in the SLC19A2 gene in an African-American female with thiamine-responsive megaloblastic anemia syndrome. 1499 41

Thiamine-responsive megaloblastic anemia syndrome (TRMA) is an autosomal recessive disorder with features that include megaloblastic anemia, mild thrombocytopenia and leukopenia, sensorineural deafness and diabetes mellitus. In this disease, the active thiamine uptake into cells is disturbed. Treatment with pharmacological doses of thiamine ameliorates the megaloblastic anemia and diabetes mellitus. Previous studies have demonstrated that the disease is caused by mutations in the SLC19A2 gene encoding a high-affinity thiamine transporter. We present a 5-yr-old-boy with TRMA and, because of its rarity, we review the literature.
Pediatr Diabetes 2002 Dec
PMID:TRMA syndrome (thiamine-responsive megaloblastic anemia): a case report and review of the literature. 1501 49

Circulat is a systemic standardized plant extract formulation that was developed for the prevention of severe manifestations of type 2 diabetes such as necrotic damage of the plantar foot. With the aim of revealing the molecular mechanisms underlying Circulat's biological activity, the effects of Circulat treatment on gene expression levels were examined in the cultured human fibroblast cell line MRC-5 using Affymetrix oligonucleotide microarrays. The analysis identified 187 genes, the expression levels of which underwent significant changes upon Circulat treatment. These include four genes (IL6, HMGA1, SLC19A2 and C4A) that have been implicated previously in the development of diabetes. A large proportion of the identified genes are involved in energy metabolism, protein synthesis, glucose metabolism and signaling pathways. Synergistic action of the Circulat components has also been revealed. Prospective applications of microarray analysis in phytopharmacology are discussed.
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PMID:Analysis of effects of the herbal preparation Circulat on gene expression levels in cultured human fibroblasts. 1751 33

Thiamine-responsive megaloblastic anaemia (TRMA) is a rare autosomal recessive condition, characterized by megaloblastic anaemia, non-autoimmune diabetes mellitus, and sensorineural hearing loss. We describe three infants with TRMA from two consanguineous Pakistani families, who were not known to be related but originated from the same area in Pakistan. All children were homozygous, and the parents were heterozygous for a c.196G>T mutation in the SLC19A2 gene on chromosome 1q23.3, which encodes a high-affinity thiamine transporter. The result is an abnormal thiamine transportation and vitamin deficiency in the cells. Thiamine in high doses (100-200 mg/d) reversed the anaemia in all our patients. Two patients discontinued insulin treatment successfully after a short period, while the third patient had to continue with insulin. The hearing loss persisted in all three children. The diagnosis of TRMA should be suspected in patients with syndromic diabetes including hearing loss and anaemia, even if the latter is only very mild and, particularly, in the case of consanguinity.
Pediatr Diabetes 2007 Aug
PMID:Thiamine-responsive megaloblastic anaemia: a cause of syndromic diabetes in childhood. 1765 67

Reported here is a 2-year-old girl who was diagnosed to have thiamine-responsive megaloblastic anemia during evaluations for her bilateral neurosensorial deafness. Besides reporting a new mutation on the gene SLC19A2 for the first time in the literature, we highlight the recognition of this syndrome--when megaloblastic anemia and diabetes mellitus coexists--and the role of thiamine replacement for the treatment of both disorders.
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PMID:A novel mutation in the SLC19A2 gene in a Turkish female with thiamine-responsive megaloblastic anemia syndrome. 1861 93

Thiamine-responsive megaloblastic anemia syndrome is an autosomal recessive disorder characterized by diabetes mellitus, megaloblastic anemia and sensorineural hearing loss. Mutations in the SLC19A2 gene, encoding a high-affinity thiamine transporter protein, THTR-1, are responsible for the clinical features associated with thiamine-responsive megaloblastic anemia syndrome in which treatment with pharmacological doses of thiamine correct the megaloblastic anemia and diabetes mellitus. The anemia can recur when thiamine is withdrawn. Thiamine may be effective in preventing deafness if started before two months. Our patient was found homozygous for a mutation, 242insA, in the nucleic acid sequence of exon B, with insertion of an adenine introducing a stop codon at codon 52 in the high-affinity thiamine transporter gene, SLC19A2, on chromosome 1q23.3.
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PMID:Thiamine-responsive megaloblastic anemia: early diagnosis may be effective in preventing deafness. 1981 79

Thiamine-responsive megaloblastic anemia (TRMA) syndrome usually associated with diabetes mellitus, anemia and deafness, due to mutations in SLC19A2, encoding a thiamine transporter protein. The onset of disease is usually seen during infancy or at early childhood and most of the TRMA patients are originated from consanguineous families. In this case, we report a 5-month-old boy who had diagnosis of TRMA during evaluations for his anemia and thrombocytopenia. The diagnosis of TRMA should be kept in mind in differential diagnosis of megaloblastic anemia especially in the populations where the consanguinity is frequent.
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PMID:Thiamine-responsive megaloblastic anemia syndrome. 2083 54

Thiamine-responsive megaloblastic anemia (TRMA) syndrome is an uncommon autosomal recessive disorder. The disease is caused by mutations in the gene, SLC19A2, encoding a high-affinity thiamine transporter, which disturbs the active thiamine uptake into cells. Major features include megaloblastic anemia, diabetes mellitus, and sensorineural deafness. Cardiac malformations with conduction defects and/or dysrhythmias, have also been described in some patients. To our knowledge, only 13 TRMA patients with cardiac defects have been reported. Here, we describe the first case of TRMA syndrome with atrial standstill, probably caused by a 2 base-pair deletion in exon 4 (1147delGT) of the gene SLC19A2.
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PMID:Thiamine-responsive megaloblastic anemia syndrome with atrial standstill: a case report. 2128 1


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