Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Glucose uptake across the sarcolemma is regulated by a family of membrane proteins called glucose transporters (GLUTs), which includes GLUT4 (the major cardiac isoform) and GLUT12 (a novel, second insulin-sensitive isoform). Potential regional patterns in glucose transport across the cardiac chambers have not been examined; thus, we hypothesized that insulin-responsive GLUT4 and -12 protein and gene expression would be chamber specific in healthy subjects and during chronic heart failure (HF). Using a canine model of tachypacing-induced, progressive, chronic HF, total GLUT protein and messenger RNA in both ventricles and atria (free wall and appendage) were investigated by immunoblotting and real-time PCR. In controls, GLUT4, but not GLUT12, protein content was significantly higher in the atria compared with the ventricles, with the highest content in the right atrium (RA; P < 0.001). GLUT4 and GLUT12 mRNA levels were similar across the cardiac chambers. During chronic HF, GLUT4 and GLUT12 protein content was highest in the left ventricle (LV; by 2.5- and 4.2-fold, respectively, P < 0.01), with a concomitant increase in GLUT4 and GLUT12 mRNA (P < 0.001). GLUT4, but not GLUT12, protein content was decreased in RA during chronic HF (P = 0.001). In conclusion, GLUT4 protein was differentially expressed across the chambers in the healthy heart, and this regional pattern was reversed during HF. Our data suggest that LV was the primary site dependent on both GLUT4 and GLUT12 during chronic HF. In addition, the paradoxical decrease in GLUT4 content in RA may induce perturbations in atrial energy production during chronic HF.
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PMID:Chronic heart failure selectively induces regional heterogeneity of insulin-responsive glucose transporters. 2184 35

Cardiomyopathies-associated metabolic pathologies (e.g., type 2 diabetes and insulin resistance) are a leading cause of mortality. It is known that the association between these pathologies works in both directions, for which heart failure can lead to metabolic derangements such as insulin resistance. This intricate crosstalk exemplifies the importance of a fine coordination between one of the most energy-demanding organs and an equilibrated carbohydrate metabolism. In this light, to assist in the understanding of the role of insulin-regulated glucose transporters (GLUTs) and the development of cardiomyopathies, we have developed a model for glut12 deficiency in zebrafish. GLUT12 is a novel insulin-regulated GLUT expressed in the main insulin-sensitive tissues, such as cardiac muscle, skeletal muscle, and adipose tissue. In this study, we show that glut12 knockdown impacts the development of the embryonic heart resulting in abnormal valve formation. Moreover, glut12-deficient embryos also exhibited poor glycemic control. Glucose measurements showed that these larvae were hyperglycemic and resistant to insulin administration. Transcriptome analysis demonstrated that a number of genes known to be important in cardiac development and function as well as metabolic mediators were dysregulated in these larvae. These results indicate that glut12 is an essential GLUT in the heart where the reduction in glucose uptake due to glut12 deficiency leads to heart failure presumably due to the lack of glucose as energy substrate. In addition, the diabetic phenotype displayed by these larvae after glut12 abrogation highlights the importance of this GLUT during early developmental stages.
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PMID:GLUT12 deficiency during early development results in heart failure and a diabetic phenotype in zebrafish. 2532 3

Heart consumes more energy than any other organ. It can utilize various metabolic substrates as a source of energy. The primary substrates are free fatty acids, especially long-chain fatty acids and glucose. The lipid bilayer of plasmalemma is impermeable for glucose. Therefore, glucose transport across the plasma membrane is mediated via glucose transporters. In human, cardiac cells are expressed as 2 families of glucose transporters: GLUTs and SGLTs. These transport proteins are GLUT1, GLUT3, GLUT8, GLUT10, GLUT11, GLUT12 and SGLT1. In human heart, GLUT4 is the major isoform that represents approximately 70% of the total glucose transporters. The changes observed in diabetic heart showed that type 1 diabetes mellitus alters the expression and translocation of GLUT4 and GLUT8 in the atria. In diabetic atria, the content in cell surface of these glucose transporters is downregulated. Expression of SGLT1, is increased in patients with end-stage cardiomyopathy secondary to type 2 diabetes. Increased expression of SGLT1 is a compensatory mechanism to the reduction in cardiac GLUT1 and GLUT4 expression. In animal model of type 1 diabetes, the expression of Sglt1 transporter is significantly decreased, and in the animal model of type 2 diabetes it is significantly increased. In heart diseases, such as cardiac hypertrophy (that is similar to fetal heart), heart failure and myocardial ischemia different perturbations in expression of glucose transporters are observed, especially in GLUT1 and GLUT4, due to changes in heart glucose metabolism. In this article, the functions of glucose transporters in healthy heart and in cardiac diseases are reviewed.
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PMID:Glucose transporters in healthy heart and in cardiac disease. 2803 63