Lipid metabolism regulation

Transport devices, e.g. for ions, oxygen, and lipids Metabolic regulators, including hormones. 

Vanadium 15 mg Lipid metabolism, regulation of cholesterol synthesis, ATPases Unknown Unknown... 

FABPs have been implicated in transmembrane and intracellular transport of fatty acids (Veerkamp et al., 1991 Storch and Thumser, 2000). These are a group of tissue-specific proteins of about 14-15 kDa that bind long-chain fatty acids (C16-C20) with high affinity and a molar stoichiometry of 1 1. Most bind unsaturated fatty acids with higher affinity than saturated fatty acids. In addition to transport functions it has been proposed that they modulate specific enzymes of lipid metabolism, regulate expression of fatty acid-responsive genes, maintain cellular membrane fatty acid levels, and reduce the concentration of fatty acids in the cell, thereby removing their inhibitory effect on metabolic processes. 

The adrenal glands, which are divided into the medulla (core) and the cortex (outer layer), furnish catecholamines and steroids, respectively. The catecholamines are hormonally active, and consist of norepinephrine and epinephrine. Steroids variously affect carbohydrate, protein, and lipid metabolism, regulate the sall/water losses of the kidneys, and affect sexual development and function. Androgens and estrogens fall in the last-mentioned category. Another adrenal hormone of note is ACTH, or adrenocorticotropic hormone. Cortisol is an adrenal product, which can be converted to cortisone. 

NR0B2 t Nuclear receptor subfamily 0, group B, member 2 Lipid metabolism/regulation of cholesterol biosynthesis... 

Protein kinase A (PKA) is a cyclic AMP-dependent protein kinase, a member of a family of protein kinases that are activated by binding of cAMP to their two regulatory subunits, which results in the release of two active catalytic subunits. Targets of PKA include L-type calcium channels (the relevant subunit and site of phosphorylation is still uncertain), phospholam-ban (the regulator of the sarcoplasmic calcium ATPase, SERCA) and key enzymes of glucose and lipid metabolism. 

As the RPE plays an important role in lipid metabolism and regulation of dynamic transport between the choriocapillaris and photoreceptors, it is important to determine whether carotenoids affect these pathways in the RPE. 

Peroxisome-proliferator activated receptors (PPARs) are lipid-activated transcription factors exerting several functions in development and metabolism. PPARa is implicated in the regulation of lipid metabolism, lipoprotein synthesis, and inflammatory response in liver and other tissues. 

The neurohormonal control of lipid metabolism chiefly affects the mobilization and synthesis of triglycerides in the fat tissue. The lipolysis in tissues is dependent upon the activity of triglyceride lipase. All the regulators that favour the conversion of the inactive (nonphosphorylated) lipase to the active (phosphoiylated) one, stimulate the lipolysis and the release of fatty acids into the blood. Adrenalin... 

PPARa GR HNF4a 4A 2B6, 2C9, 3A4, 3A5 2A6, 2B6, 2C9, 2D6, 3 A, 7A1 Fatty add metabolism regulation I m munore sponse regulation Carbohydrate, lipid, protein and... 

Glycolysis is the major route of carbohydrate metabolism in all cell types and the TCA is a focal point allowing the integration of carbohydrate, amino acid and lipid metabolism. The two pathways are illustrated in Figures 3.9 and 3.14. These two well-known pathways exemplify many of the general principles of metabolic regulation described above. 

Peroxisome proliferator-activated receptors (PPARs) PPREs Regulate multiple aspects of lipid metabolism Activated by fibrates and thiazolidinediones Zinc finger... 

The best-known effect of APOE is the regulation of lipid metabolism (see Fig. 10.13). APOE is a constituent of TG-rich chylomicrons, VLDL particles and their remnants, and a subclass of HDL. In addition to its role in the transport of cholesterol and the metabolism of lipoprotein particles, APOE can be involved in many other physiological and pathological processes, including immunoregu-lation, nerve regeneration, activation of lipolytic enzymes (hepatic lipase, lipoprotein lipase, lecithin cholesterol acyltransferase), ligand for several cell receptors, neuronal homeostasis, and tissue repair (488,490). APOE is essential... 

ASBT has a complex regulatory system reflecting the importance of this transporter to bile-acid pool size and bile-acid synthesis rates. Hepatic nuclear factor la (HNF-la) is necessary for expression of ASBT as knockout mice showed no expression and had defective bile-acid transport.Conversely, FXR-null mice showed no difference in expression of ASBT, showing that FXR plays no part in regulation of ASBT. In man, HNF-la controls baseline promoter activity of the ASBT gene as the minimal construct with full promoter activity was found to have 3 HNF-la binding sites. These authors also showed that the promoter construct bound peroxisome proliferator activated receptor a (PPARa)/9 cis retinoic acid receptor heterodimer, demonstrating a link between bile-acid absorption and hepatic lipid metabolism mediated by PPARa. 

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