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Refsum s disease

The a-oxidation pathway is defective in Refsum s disease, an inherited metabolic disorder that results in defective night vision, tremors, and other neurologic abnormalities. These symptoms are caused by accumulation of phytanic acid in the body. Treatment of Refsum s disease requires a diet free of chloro-... [Pg.796]

Phytanic acid, the product of chlorophyll that causes problems for individuals with Refsum s disease, is 3,7,11,15-tetramethyl hexa-decanoic acid. Suggest a route for its oxidation that is consistent with what you have learned in this chapter. Hint The methyl group at C-3 effectively blocks hydroxylation and normal /3-oxidation. You may wish to initiate breakdown in some other way.)... [Pg.800]

Refsum s disease is an autosomal recessive peroxisomal disorder characterized by accumulation of phytanic acid and other 3-alkyl-branched fatty acids [55]. Patients develop hypertrophic demyelinative polyneuropathy, retinitis pigmentosa, ichthyosis and deafness. The disorder can be successfully treated by institution of a diet poor in phytanic acid, in conjunction with plasmapheresis to remove circulating phytanic acid. [Pg.624]

Refsum s disease AR Oxidation of branched chain fatty acids phytan-olyl CoA 2-hydroxylase in some cases Increase of branched-chain phytanic acid, especially in PNS myelin 1, 38, Ch. 40... [Pg.647]

IRD, infantile Refsum s disease NALD, neonatal adrenoleukodystrophy ZS, Zellweger s syndrome. [Pg.690]

Acyl-CoA oxidase deficiency D-bifunctional protein deficiency Racemase deficiency Refsum s disease... [Pg.690]

Refsum s disease. This disorder, first described nearly 60 years ago, was recently been shown due to a defect in the enzyme phytanoyl-CoA hydroxylase. Phytanic acid is a 3-methyl fatty acid that because of this methyl group cannot be oxidized directly. It is degraded by a peroxisomal a-oxidation to pristanic acid, a 2-methyl fatty acid which can be degraded by P-oxidation. The principal clinical features of Refsum s disease are progressive polyneuropathy, retinal degeneration, hearing loss, cardiomyopathy and ichthyosis, beginning in late childhood or later. [Pg.691]

Alkyl PAT, alkyl-dihydroxy phosphate synthase Bif, bifunctional enzyme DHAPAT, dihydroxyphosphate acyltransferase deficiency DHCA, dihydroxycholestanoic acid N, normal nd, not determined Ox, acyl-CoA oxidase Rac, 2-methylacyl-CoA racemase RCDP, rhizomelic chondrodysplasia punctata Ref, Refsum s disease THCA, trihydroxycholestanoic acid VLCFA, very-long-chain fatty acid. [Pg.691]

Globoid leukodystrophy Metachromatic leukodystrophy X-linked adrenoleukodystrophy Refsum s disease Cystinosis... [Pg.692]

Peroxisomal disorders (Zellweger syndrome, Refsum s disease, neonatal adre-noleukodystrophy) are characterised by defective peroxisome biogenesis, or, being present, peroxisomes lacking / -oxidative enzymes. In the BA biosynthetic pathway, dihydroxycoprostanic acid (DHCA) and trihydroxycoprostanic acid (THCA) are /1-oxidised in peroxisomes to produce CA and CDCA, respectively, whereas peroxisomal disorders cause a defective oxidation of the BA precursor side chain, which leads to an accumulation of C27 bile acids, notably 3 ,7 -dihydroxy-5/3-cholesta-noic acid (DHCA) and 3a,7a,12a-trihydroxy-5/l-cholestanoic acid (THCA), in the plasma and urine of affected patients. [Pg.611]

Herndon, J., Steinberg, D., and Uhlendorf, B., Refsum s disease defective oxidation of phytanic acid in tissue cultures derived from homozygotes and heterozygotes, N. Engl. J. Med., 281, 1034, 1969. [Pg.94]

H-5) Refsum s disease. There is inability to break down ingested phytanic acid (a branched chain fatty acid from the phytol isoprenoid of chlorophyl). This leads to severe neurological symptoms. [Pg.53]

Cerebrohepatorenal (Zellweger s) syndrome Infantile Refsum s disease Neonatal adrenoleukodystrophy Rhizomelic chondrodysplasia punctata Hyperpipecolic acidemia Genetic diseases with generalized impairment of peroxisomal function but normal number of peroxisomes... [Pg.1786]

Pseudo-ZeUwegePs syndrome Genetic diseases with a single enzyme defect and a normal number of peroxisomes X"linked adrenoleukodystrophy Adult Refsum s disease Acatalasemia... [Pg.1786]

In Refsum s disease, an autosomal recessive disorder, the defect is probably in the a-hydroxylation of phytanic acid. Phytanic acid is a 20-carbon, branched-chain fatty acid derived from the plant alcohol phytol, which is present as an ester in chlorophyll. Thus, its origin in the body is from dietary sources. The oxidation of phytanic acid is shown in Figure 18-6. The clinical characteristics of Refsum s disease include peripheral neuropathy and ataxia, retinitis pigmentosa, and abnormalities of skin and bones. Significant improvement has been observed when patients are kept on low-phytanic acid diets for prolonged periods (e.g., diets that exclude dairy and ruminant fat). [Pg.374]

Refsum s Disease In a specific form of autosomal recessive retinitis pigmentosa, the inborn error of... [Pg.70]

Eldjarn L, Stokke O, Try K. 1966. Alpha-oxidation of branched chain fatty acids in man and its failure in patients with Refsum s disease showing phytanic acid accumulation. Scand J Clin Lab Invest 18 694-695. [Pg.81]

Scotto JM, Hadchouel M, Odievre M, Laudat MH. Saudubray JM, Dulac (). et al. Infantile phytanic acid storage disease, a possible variant of Refsum s disease three cases, including ultrastructural studies of the liver. J Inherited Metab Dis 1982 5(2) 83—90. [Pg.270]

The ability to oxidize phytanic acid is critical because large quantities of this molecule are found in the diet. In Refsum s disease (also referred to as phytanic acid storage syndrome) a build-... [Pg.388]

Phytanic acid is an unusual fatty acid which accumulates in patients with Refsum s disease. Phytanic acid is derived from phytol, a constituent of chlorophyll (Figure 18.20). Phytanic acid contains a methyl group on carbon number three and this prevents / -oxidation from occurring. [Pg.2320]

Deficient in Refsum s disease - patients accumulate phytanic acid (derived from phytol)... [Pg.2425]


See other pages where Refsum s disease is mentioned: [Pg.796]    [Pg.188]    [Pg.42]    [Pg.513]    [Pg.652]    [Pg.690]    [Pg.693]    [Pg.279]    [Pg.294]    [Pg.147]    [Pg.63]    [Pg.220]    [Pg.583]    [Pg.374]    [Pg.111]    [Pg.650]    [Pg.152]    [Pg.2320]   
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See also in sourсe #XX -- [ Pg.374 ]

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See also in sourсe #XX -- [ Pg.3 , Pg.29 , Pg.30 , Pg.31 , Pg.32 , Pg.33 , Pg.35 ]




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