Long-chain acyl-CoA dehydrogenase LCAD

Very-long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is an autosomal recessive condition. In the mid 1980s, patients with VLCAD deficiency were initially described as having long-chain acyl-CoA dehydrogenase (LCAD) deficiency. However, without exception, once the VLCAD protein was identified, affected patients were shown to have no detectable VLCAD protein by immunobiot analy-sis or to harbor disease-causing mutations in the VLCAD... 

Long-chain acyl-CoA dehydrogenase is a soluble mitochondrial protein that was thought to be essential in humans for the mitochondrial (3-oxidation of long chain fatty acids. In mouse, LCAD is highly expressed in most tissues and has a broad activity with acyl-CoA substrates of 6 20 carbons, showing higher activity with lauroyl-CoA (C12-CoA). Mouse mutation models of LCAD deficiency mimic phenotypes of human VLCAD and MCAD deficiency. In humans, however, there are currently no reported cases of human LCAD deficiency. The presence of this enzyme is undetectable in skeletal muscle, where (3-oxidation... 

The acyl-Co A dehydrogenases are a family of mitochondrial flavoenzymes involved in fatty acid and branched chain amino-acid metabolism. In addition to long chain acyl-Co A dehydrogenases (LCADs), there are short/ branched chain acyl-CoA dehydrogenase (SBCAD) that act on 2-methyl branched chain acyl-CoA substrates of varying chain lengths. 

Acyl-CoA dehydrogenases (ACADs), flavoproteins found in the mitochondria, are involved in /3-oxidation of fatty acids. Currently, there are five types of ACADs classified according to substrate specificity. Short-chain ACAD (SCAD), medium-chain ACAD (MCAD), long-chain ACAD (LCAD), and very long-chain ACAD... 

Defects of fatty acid catabolism, with the exception of SCAD deficiency, generally have elevation of more than one characteristic metabolite. MCAD deficiency is characterized by accumulation of C6, C8 (mainly) and C10 l species. LCAD and VLCAD are characterized by accumulation of C14 l, C14 2 and (usually) C16 and C18 l species. LCHADD and TFP deficiencies are characterized by the accumulation of OH-C16, 0H-C18 1 and usually at least one of the other long-chain species C14 1, C16 and C18 l. The CPT-II and CAT (carnitine/acylcarnitine translocase) deficiencies are characterized by marked elevation of both C16 and C18 1, but not C14 1. Multiple acyl-CoA deficiency (MAD) has several different etiologies, including electron transferring protein (ETF) deficiency, ETF-dehydrogenase deficiency and riboflavin deficiency. Disease patterns vary considerably. In severe forms of the disorder, a generalized marked elevation of mxiltiple intermediates is observed. CPT-I should be suspected when both C16 and Cl8 1 are very low in whole blood, especially if free carnitine is normal or elevated. 

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