Biomaterial Database

Evidence for a primary defect of lipoamide dehydrogenase in Friedreich's ataxia. 1978

R A Kark, and M Rodriguez-Budelli, and J P Blass

There is now a great deal of evidence to link genetic defects of pyruvate metabolism to brain disease. Experimental evidence is reviewed in Chapter 12, and clinical evidence has been reviewed above. Severe lesions of components of the pyruvate dehydrogenase complex are associated with severe generalized brain disease, and milder defects with inherited ataxias. Nearly half of one series of our ataxic patients had deficient activity of pyruvate dehydrogenase, and 40% of another series have deficient activity of the lipoamide dehydrogenase component. This last group corresponds to 60% of the patients with Friedreich's ataxia and its clinical variants at UCLA. There is an association between defective activity of lipoamide dehydrogenase and disease, and the data suggest there is a structural mutation of the gene for the enzyme. Preliminary studies suggest that obligate heterozygotes as a group have enzyme activities between those for controls and those for patients. Moreover, the obligate heterozygotes from families in which there are kinetic defects of lipoamide dehydrogenase also appear to have kinetic abnormalities of the enzyme. The ataxic patients with reduced lipoamide dehydrogenase activity currently fall into two clinical groups. One is ragged-red ataxia, and the other is a disorder that is a subgroup of the classic Friedreich's ataxia syndrome. Studies need to be undertaken on a larger group of patients, with more diverse inherited ataxias, to test the present clinical associations of the enzyme defect. A dietary treatment derived from a knowledge of the presumed defect has modified the ataxia that is associated with defects of pyruvate decarboxylase, but the diet has not yet been tested with defects of lipoamide dehydrogenase.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008058	Dihydrolipoamide Dehydrogenase	A flavoprotein containing oxidoreductase that catalyzes the reduction of lipoamide by NADH to yield dihydrolipoamide and NAD+. The enzyme is a component of several MULTIENZYME COMPLEXES.	Lipoamide Dehydrogenase,NAD Diaphorase,NADH Diaphorase,Diaphorase (Lipoamide Dehydrogenase),Dihydrolipoyl Dehydrogenase,Glycine Decarboxylase Complex L-Protein,L-Protein, Glycine Decarboxylase Complex,Lipoamide Dehydrogenase, Valine,Lipoic Acid Dehydrogenase,Lipoyl Dehydrogenase,Valine Lipoamide Dehydrogenase,Dehydrogenase, Dihydrolipoamide,Dehydrogenase, Dihydrolipoyl,Dehydrogenase, Lipoamide,Dehydrogenase, Lipoic Acid,Dehydrogenase, Lipoyl,Dehydrogenase, Valine Lipoamide,Diaphorase, NAD,Diaphorase, NADH,Glycine Decarboxylase Complex L Protein
D008297	Male		Males
D001792	Blood Platelets	Non-nucleated disk-shaped cells formed in the megakaryocyte and found in the blood of all mammals. They are mainly involved in blood coagulation.	Platelets,Thrombocytes,Blood Platelet,Platelet,Platelet, Blood,Platelets, Blood,Thrombocyte
D005260	Female		Females
D005621	Friedreich Ataxia	An autosomal recessive disease, usually of childhood onset, characterized pathologically by degeneration of the spinocerebellar tracts, posterior columns, and to a lesser extent the corticospinal tracts. Clinical manifestations include GAIT ATAXIA, pes cavus, speech impairment, lateral curvature of spine, rhythmic head tremor, kyphoscoliosis, congestive heart failure (secondary to a cardiomyopathy), and lower extremity weakness. Most forms of this condition are associated with a mutation in a gene on chromosome 9, at band q13, which codes for the mitochondrial protein frataxin. (From Adams et al., Principles of Neurology, 6th ed, p1081; N Engl J Med 1996 Oct 17;335(16):1169-75) The severity of Friedreich ataxia associated with expansion of GAA repeats in the first intron of the frataxin gene correlates with the number of trinucleotide repeats. (From Durr et al, N Engl J Med 1996 Oct 17;335(16):1169-75)	Friedreich Disease,Hereditary Spinal Sclerosis,Sclerosis, Hereditary Spinal,Friedreich Familial Ataxia,Friedreich Hereditary Ataxia,Friedreich Hereditary Spinal Ataxia,Friedreich Spinocerebellar Ataxia,Friedreich's Ataxia,Friedreich's Disease,Friedreich's Familial Ataxia,Friedreich's Hereditary Ataxia,Friedreich's Hereditary Spinal Ataxia,Hereditary Spinal Ataxia, Friedreich,Hereditary Spinal Ataxia, Friedreich's,Ataxia, Friedreich,Ataxia, Friedreich Familial,Ataxia, Friedreich Hereditary,Ataxia, Friedreich Spinocerebellar,Ataxia, Friedreich's,Ataxia, Friedreich's Familial,Ataxia, Friedreich's Hereditary,Ataxias, Friedreich,Ataxias, Friedreich's Hereditary,Disease, Friedreich,Disease, Friedreich's,Familial Ataxia, Friedreich,Familial Ataxia, Friedreich's,Friedreich Ataxias,Friedreich's Hereditary Ataxias,Friedreichs Familial Ataxia,Friedreichs Hereditary Ataxia,Hereditary Ataxia, Friedreich,Hereditary Ataxia, Friedreich's,Hereditary Ataxias, Friedreich's,Hereditary Spinal Scleroses,Scleroses, Hereditary Spinal,Spinal Scleroses, Hereditary,Spinal Sclerosis, Hereditary,Spinocerebellar Ataxia, Friedreich
D006579	Heterozygote	An individual having different alleles at one or more loci regarding a specific character.	Carriers, Genetic,Genetic Carriers,Carrier, Genetic,Genetic Carrier,Heterozygotes
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001259	Ataxia	Impairment of the ability to perform smoothly coordinated voluntary movements. This condition may affect the limbs, trunk, eyes, pharynx, larynx, and other structures. Ataxia may result from impaired sensory or motor function. Sensory ataxia may result from posterior column injury or PERIPHERAL NERVE DISEASES. Motor ataxia may be associated with CEREBELLAR DISEASES; CEREBRAL CORTEX diseases; THALAMIC DISEASES; BASAL GANGLIA DISEASES; injury to the RED NUCLEUS; and other conditions.	Coordination Impairment,Dyssynergia,Incoordination,Ataxia, Appendicular,Ataxia, Limb,Ataxia, Motor,Ataxia, Sensory,Ataxia, Truncal,Ataxy,Dyscoordination,Lack of Coordination,Tremor, Rubral,Appendicular Ataxia,Appendicular Ataxias,Ataxias,Ataxias, Appendicular,Ataxias, Limb,Ataxias, Motor,Ataxias, Sensory,Ataxias, Truncal,Coordination Impairments,Coordination Lack,Impairment, Coordination,Impairments, Coordination,Incoordinations,Limb Ataxia,Limb Ataxias,Motor Ataxia,Motor Ataxias,Rubral Tremor,Rubral Tremors,Sensory Ataxia,Sensory Ataxias,Tremors, Rubral,Truncal Ataxia,Truncal Ataxias
D015325	Pyruvate Dehydrogenase Complex Deficiency Disease	An inherited metabolic disorder caused by deficient enzyme activity in the PYRUVATE DEHYDROGENASE COMPLEX, resulting in deficiency of acetyl CoA and reduced synthesis of acetylcholine. Two clinical forms are recognized: neonatal and juvenile. The neonatal form is a relatively common cause of lactic acidosis in the first weeks of life and may also feature an erythematous rash. The juvenile form presents with lactic acidosis, alopecia, intermittent ATAXIA; SEIZURES; and an erythematous rash. (From J Inherit Metab Dis 1996;19(4):452-62) Autosomal recessive and X-linked forms are caused by mutations in the genes for the three different enzyme components of this multisubunit pyruvate dehydrogenase complex. One of the mutations at Xp22.2-p22.1 in the gene for the E1 alpha component of the complex leads to LEIGH DISEASE.	Ataxia with Lactic Acidosis, Type I,Lactic Acidosis with Ataxia, Type I,Ataxia with Lactic Acidosis,Ataxia with Lactic Acidosis I,Ataxia, Intermittent, with Abnormal Pyruvate Metabolism,Ataxia, Intermittent, with Pyruvate Dehydrogenase, or Decarboxylase, Deficiency,Intermittent Ataxia with Pyruvate Dehydrogenase Deficiency,Juvenile Pyruvate Dehydrogenase Complex Deficiency Disease,Neonatal Pyruvate Dehydrogenase Complex Deficiency Disease,PDH Deficiency,PDHC Deficiency,PDHC Deficiency Disease,Pyruvate Decarboxylase Deficiency,Pyruvate Dehydrogenase Complex Deficiency,Pyruvate Dehydrogenase Complex Deficiency Disease, Juvenile,Pyruvate Dehydrogenase Complex Deficiency Disease, Neonatal,Pyruvate Dehydrogenase Deficiency,Type I Ataxia with Lactic Acidosis,Deficiency, PDH,Deficiency, PDHC,Deficiency, Pyruvate Decarboxylase,Deficiency, Pyruvate Dehydrogenase