Fatty Acid Binding Proteins FABPs

The hypothesis of the participation of those cholesterol transporters (NPCILI and ABCAl) in the carotenoid transport remains to be confirmed, especially at the in vivo human scale. If the mechanism by which carotenoids are transported through the intestinal epithelial membrane seems better understood, the mechanism of intracellular carotenoid transport is yet to be elucidated. The fatty acid binding protein (FABP) responsible for the intracellular transport of fatty acids was proposed earlier as a potential transporter for carotenoids. FABP would transport carotenoids from the epithelial cell membrane to the intracellular organelles such as the Golgi apparatus where CMs are formed and assembled, but no data have illustrated this hypothesis yet. 

P2 protein. PNS myelin contains a positively charged protein different from MBP that is referred to as P2 (Mr — 15,000). It is unrelated in sequence to MBP and is a member of a family of cytoplasmic fatty acid binding proteins (FABP) that are present in a variety of cell types [25]. The amount of P2 protein is variable among species, accounting for about 15% of total protein in bovine PNS myelin, 5% in humans and less than 1% in rodents. P2 protein is generally considered a PNS myelin protein but it is expressed in small amounts in CNS myelin sheaths of some species. P2 is an antigen for experimental allergic neuritis, the PNS counterpart of EAE (see Chs 36 and 38). P2 appears to be present in the major dense line of myelin sheaths, where it may play a structural role similar to MBP... 

Fatty acid utilized by muscle may arise from storage triglycerides from either adipose tissue depot or from lipid stores within the muscle itself. Lipolysis of adipose triglyceride in response to hormonal stimulation liberates free fatty acids (see Section 9.6.2) which are transported through the bloodstream to the muscle bound to albumin. Because the enzymes of fatty acid oxidation are located within subcellular organelles (peroxisomes and mitochondria), there is also need for transport of the fatty acid within the muscle cell this is achieved by fatty acid binding proteins (FABPs). Finally, the fatty acid molecules must be translocated across the mitochondrial membranes into the matrix where their catabolism occurs. To achieve this transfer, the fatty acids must first be activated by formation of a coenzyme A derivative, fatty acyl CoA, in a reaction catalysed by acyl CoA synthetase. 

The FFA released by the adipocytes is collected by albumin and is transported to the various tissues in the blood. The albumin-FFA complex is able to cross the endothelial barrier in the capillaries and enter the interstitial space and so deliver this important fuel to the plasma membrane of the cell. To facilitate the transport of free fatty acids across the plasma membrane and within the cell, other transport proteins are present these are known as fatty acid binding proteins (FABP). 

The very low solubility of fatty acids poses a problem for their transport within the cell, as it does in the blood. The problem is solved by the presence of the fatty acid binding protein (FABP). It binds fatty acids at the inner surface of... 

Long-chain fatty acids were previously believed to enter cells by diffusion, but evidence now implicates a family of protein-mediated transporters, the fatty acid transport protein (FATP) family. Internally, fatty acid-binding proteins (FABPs) constimte a family of low-molecular-weight proteins that function as intracellular transporters of fatty acids. 

Ileal lipid-binding protein (ILEPs) and other fatty acid binding proteins (FABPs) were the targets of a CRID/CPCA study by Kurz et al. [14]. ILEP is a cytosolic lipid... 

Fatty acids C10 0 and longer have considerable detergent properties and are not found free within cells. Most cells contain small intracellular fatty acid-binding proteins (FABPs), which are thought to function in part to buffer the detergent effects of free fatty acids. In the commercial sense, soaps are the water-soluble sodium or potassium salts of fatty acids, which are made from fats and oils by treating them chemically with a strong base such as NaOH or KOH. 

Determination of mitochondrial GOT (mGOT = 80%) is recommended as an additional laboratory parameter for the detection of persistent alcohol abuse, particularly in those cases where GDH measurements are inconclusive. Mitochondrial GOT (mGOT) serves as a fatty acid-binding protein (FABP). This might help to explain the increased uptake of fatty acids in hepatocytes due to alcohol abuse. 

Transport of fatty acids inside the parenchymal cells, that is, from the plas-malentma to the intracellular site of conversion, is most likely mediated by fatty acid-binding proteins (FABPs). At least seven different isoforms of this low molecular weight protein (15 kDa) have been described, among which there is the liver-type and muscle-type FABP (Glatz and Van der Vusse, 1990). FABPs facilitate intracellular transport of fatty acids by increasing their solubility in the aqueous environment. 

Comparison of SCP2 with other low molecular weight proteins (a) Fatty-acid-binding protein (FABP)... 

Unesterified fatty acids within cells are commonly bound by fatty acid-binding proteins (FABPs), which belong to a group of small cytosolic proteins that facilitate the Intracellular movement of many lipids. These proteins contain a hydrophobic pocket lined by p sheets (Figure 18-3). A long-chain fatty acid can fit into this pocket and Interact noncovalently with the surrounding protein. 

Diagnosis of cardiac muscle injury relies on the detection of biomarkers such as troponin I (Tnl), troponin C (TnC), myoglobin, fatty acid binding protein (FABP), glycogen phosporylase isoenzyeme BB (GPBB), C-reactive protein (CP), urinary albumin, creatine kinase myocardial band (CK-MB), and brain (B-type) natriuretic peptide in blood and urine [28-30]. 

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