Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.3.1.21 (CPT)
 4,580 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A number of biochemical defects have been identified in glucose metabolism within skeletal muscle in obesity, and positive effects of weight loss on insulin resistance are also well established. Less is known about the capacity of skeletal muscle for the metabolism of fatty acids in obesity-related insulin resistance and of the effects of weight loss, though it is evident that muscle contains increased triglyceride. The current study was therefore undertaken to profile markers of human skeletal muscle for fatty acid metabolism in relation to obesity, in relation to the phenotype of insulin-resistant glucose metabolism, and to examine the effects of weight loss. Fifty-five men and women, lean and obese, with normal glucose tolerance underwent percutaneous biopsy of vastus lateralis skeletal muscle for determination of HADH, CPT, heparin-releasable (Hr) and tissue-extractable (Ext) LPL, CS, COX, PFK, and GAPDH enzyme activities, and content of cytosolic and plasma membrane FABP. Insulin sensitivity was measured using the euglycemic clamp method. DEXA was used to measure FM and FFM. In skeletal muscle of obese individuals, CPT, CS, and COX activities were lower while, conversely, they had a higher or similar content of FABP(C) and FABP(PM) than in lean individuals. Hr and Ext LPL activities were similar in both groups. In multivariate and simple regression analyses, there were significant correlations between insulin resistance and several markers of FA metabolism, notably, CPT and FABP(PM). These data suggest that in obesity-related insulin resistance, the metabolic capacity of skeletal muscle appears to be organized toward fat esterification rather than oxidation and that dietary-induced weight loss does not correct this disposition.
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PMID:Markers of capacity to utilize fatty acids in human skeletal muscle: relation to insulin resistance and obesity and effects of weight loss. 1054 88

Metabolic myopathies comprise a clinically and etiologically diverse group of disorders caused by defects in cellular energy metabolism, including the breakdown of carbohydrates and fatty acids to generate adenosine triphosphate, predominantly through mitochondrial oxidative phosphorylation. Accordingly, the three main categories of metabolic myopathies are glycogen storage diseases, fatty acid oxidation defects, and mitochondrial disorders due to respiratory chain impairment. The wide clinical spectrum of metabolic myopathies ranges from severe infantile-onset multisystemic diseases to adult-onset isolated myopathies with exertional cramps. Diagnosing these diverse disorders often is challenging because clinical features such as recurrent myoglobinuria and exercise intolerance are common to all three types of metabolic myopathy. Nevertheless, distinct clinical manifestations are important to recognize as they can guide diagnostic testing and lead to the correct diagnosis. This article briefly reviews general clinical aspects of metabolic myopathies and highlights approaches to diagnosing the relatively more frequent subtypes (Fig. 1). Fig. 1 Clinical algorithm for patients with exercise intolerance in whom a metabolic myopathy is suspected. CK-creatine kinase; COX-cytochrome c oxidase; CPT-carnitine palmitoyl transferase; cyt b-cytochrome b; mtDNA-mitochondrial DNA; nDNA-nuclear DNA; PFK-phosphofructokinase; PGAM-phosphoglycerate mutase; PGK-phosphoglycerate kinase; PPL-myophosphorylase; RRF-ragged red fibers; TFP-trifunctional protein deficiency; VLCAD-very long-chain acyl-coenzyme A dehydrogenase.
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PMID:A diagnostic algorithm for metabolic myopathies. 2042 36