Dietary cobalamin (Cbl; vitamin B12) deficiency resulted in severe growth retardation in rats, and body weight in the Cbl-deficient rats at 20 wk of age was significantly lower compared with the age-matched Cbl-sufficient control rats. In contrast, liver weight, when normalized to body weight, was greater in the Cbl-deficient rats than in the controls (p<0.05). The expression level of prolifera...

BACKGROUND Methylmalonic aciduria and homocystinuria type C (cblC), a disorder of vitamin B12 (cobalamin) metabolism caused by mutations in the MMACHC gene, presents with many systemic symptoms, including neurological, cognitive, psychiatric, and thromboembolic events. Retinal phenotypes, including maculopathy, pigmentary retinopathy, and optic atrophy are common in early onset form of the dise...

Chronic renal failure is a well-known long-term complication of methylmalonic aciduria (MMA-uria), occurring even under apparently optimal metabolic management. The onset of renal dysfunction seems to be dependent on the type of defect and vitamin B12-responsiveness. We report on a patient with a vitamin B12-responsive cobalamin A type (cblA) MMA-uria caused by a homozygous stop mutation (p.R14...

Differential screening of gerbil brain hippocampal cDNA libraries was used to search for genes expressed in ischemic, but not normal, brain. The methylmalonyl-CoA mutase (MCM) cDNA was highly expressed after ischemia and showed a 95% similarity to mouse and 91% similarity to the human MCM cDNAs. Transient global ischemia induced a fourfold increase in MCM mRNA on Northern blots from both hippoc...

We present reference intervals for total homocysteine and methylmalonic acid in plasma based on samples from 126 women (ages 20-85 years, median 49 years) and 109 men (ages 20-84 years, median 50 years). The central 0.95 interval for methylmalonic acid was 0.08-0.28 micromol/L. Supplementation with cyanocobalamin caused a nonsignificant decrease in methylmalonic acid. Supplementation with folic...

BACKGROUND Liquid chromatography-tandem mass spectrometry (LC-MS/MS) with electrospray ionization is robust and allows accurate measurement of both low- and high-molecular weight components of complex mixtures. We developed a LC-MS/MS method for the analysis of methylmalonic acid (MMA), a biochemical marker for inherited disorders of propionate metabolism and acquired vitamin B(12) deficiency. ...

methylmalonic acidemia (mma) is usually caused by a deficiency of the enzyme methylmalonyl-coa mutase (mcm), a defect in the transport or synthesis of its cofactor, adenosyl-cobalamin (cbla, cblb, cblc, cblf, cbld, and cblx), or deficiency of the enzyme methylmalonyl-coa epimerase. a comprehensive diagnostic approach involves investigations of metabolites with tandem mass spectrometry, organic ...

background: organic acids refer to a family of compounds that are intermediates in a variety of metabolic pathways. many organic acids are present in urine from clinically normal individuals. elevated levels of urine organic acids cause to the organic acidurias, disorders in which some metabolic pathways in organic acid metabolism are blocked. the present work identified major and minor urinary...

organic academia are diverse group of disorders characterized by abnormal degredation of specific amino acid in the specific catabolism due to an enzymeactivity defect which mainly due to enzyme deficiency. the majority of the classic organic acid disorders are caused by abnormal catabolism of branched-chain amino acids like lysine. maple syrup urine disease (msud), propionic acidemia, methylma...

BACKGROUND The standard screening test for vitamin B12 deficiency, measurement of total plasma vitamin B12, has limitations of sensitivity and specificity. Plasma vitamin B12 bound to transcobalamin (holoTC) is the fraction of total vitamin B12 available for tissue uptake and therefore has been proposed as a potentially useful alternative indicator of vitamin B12 status. METHODS We compared t...