Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q16795 (ubiquinone)
 5,455 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A male infant with glutaric aciduria II secondary to electron transfer flavoprotein: ubiquinone oxidoreductase deficiency is compared to previously reported cases of glutaric aciduria II. A common pattern of anomalies in patients with malformations (8/16) includes macrocephaly, large anterior fontanelle, high forehead, flat nasal bridge, telecanthus, and malformed ears. Abnormalities such as hypotonia, cerebral gliosis, heterotopias, hepatomegaly, hepatic periportal necrosis, polycystic kidneys, and genital defects in glutaric aciduria II are reminiscent of those in Zellweger syndrome, whereas elevations of glutaric, ethylmalonic, adipic, and isovaleric acids are quite distinctive. A unique ultrastructural alteration of the glomerular basement membrane was observed in the proposita. This manifestation may represent an early stage in renal cyst formation and provide a diagnostic criterion for glutaric aciduria II when enzyme studies are unavailable.
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PMID:Glutaric aciduria type II: review of the phenotype and report of an unusual glomerulopathy. 265 91

Biochemical studies have been performed in muscle, liver, leukocytes, and fibroblasts from patients suffering from the Zellweger syndrome. Oxidation rates of [1-14C]pyruvate, [U-14C]malate, and [1-14C]2-oxoglutarate were strongly reduced in skeletal muscle homogenate. Oxygen consumption in isolated skeletal muscle mitochondria could only be stimulated by ADP in the presence of ascorbate and N,N,N1,N1-tetramethyl-p-phenylenediamine. Cytochrome contents in heart muscle and liver mitochondria were normal. A very low activity of succinate-ubiquinone oxidoreductase was found in liver homogenate of two patients. From the effect of 2-thenoyltrifluoroacetone on the succinate-phenazine methosulphate oxidoreductase activity, a nearly competitive inhibition with respect to phenazine methosulphate was demonstrated in contrast with a non-competitive inhibition in controls. Normal oxidation rate of [1-14C]pyruvate and [2-14C]pyruvate was found in leucocytes and fibroblasts. Lactate and pyruvate levels were normal in serum and cerebrospinal fluid and beta-hydroxybutyrate and acetoacetate levels were normal in blood. The ratios lactate/pyruvate and beta-hydroxybutyrate/acetoacetate were normal as well. These findings point to a defect in the electron transport chain at the succinate-ubiquinone oxidoreductase level. This defect might be related to the absence of peroxisomes in the cells of Zellweger patients.
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PMID:Biochemical studies in the liver and muscle of patients with Zellweger syndrome. 687 6

Fibroblasts were cultured to determine the involvement of peroxisomes in cholesterol and dolichol synthesis. For this purpose, the behavior of cells from patients with Zellweger syndrome, with X-linked adrenoleukodystrophy, and from nondiseased control subjects was studied. Cells both after pretreatment with mevinolin and without pretreatment were incubated in a medium containing [3H]-mevalonate. In fibroblasts from patients with peroxisomal defects, the cholesterol content and mevalonate incorporation into cholesterol were decreased by 10-20% in comparison with control cells. Mevinolin pretreatment decreased the incorporation rate of [3H]-mevalonate into cholesterol but increased the labeling of ubiquinone and dolichol both in diseased and control cells. Squalene synthase activity was unchanged, whereas the activity of farnesyl-pyrophosphate synthase was increased in the diseased states. The results show that in patients with peroxisomal deficiency neither the amount nor the rate of synthesis of cholesterol and dolichol is reduced to any greater extent.
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PMID:Synthesis of mevalonate pathway lipids in fibroblasts from Zellweger and X-linked ALD patients. 1047 53

Because several studies indicated that peroxisomes are important for the biosynthesis of isoprenoids, we wanted to investigate whether a reduced availability of isoprenoids could be one of the pathogenic factors contributing to the severe phenotype of the Pex5(-/-) mouse, a model for Zellweger syndrome. Total cholesterol was determined in plasma, brain and liver of newborn mice. In none of these tissues a significant difference was observed between Pex5(-/-) and wild type or heterozygous mice. The hepatic ubiquinone content was found to be even higher in Pex5(-/-) mice as compared to wild type or heterozygous littermates. To investigate whether the Pex5(-/-) fetuses are able to synthesise their own isoprenoids, fibroblasts derived from these mice were incubated with radiolabeled mevalonolactone as a substrate for isoprenoid synthesis. No significant difference was observed between the cholesterol production rates of Pex5(-/-) and normal fibroblasts. Our results show that there is no deficiency of isoprenoids in newborn Pex5(-/-) mice, excluding the possibility that a lack of these compounds is a determinant factor in the development of the disease state before birth.
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PMID:Isoprenoid biosynthesis is not compromised in a Zellweger syndrome mouse model. 1142 Jan 71