Roger A. Peeters

Bio: Roger A. Peeters is an academic researcher from Radboud University Nijmegen. The author has contributed to research in topics: Fatty acid-binding protein & Oleic acid. The author has an hindex of 6, co-authored 6 publications receiving 608 citations.

Detection, tissue distribution and (sub)cellular localization of fatty acid-binding protein types.

Abstract: This overview of recent work on FABP types is focussed on their detection and expression in various tissues, their cellular and subcellular distribution and their binding properties. Besides the 3 well-known liver, heart and intestinal types, new types as the adipose tissue, myelin and (rat) renal FABPs have been described. Recent observations suggest the occurrence of more tissue-specific types, e.g. in placenta and adrenals. Heart FABP is widely distributed and present in skeletal muscles, kidney, lung, brain and endothelial cells. The cellular distribution of FABP types appears to be related to the function of the cells in liver, muscle and kidney. The presence of FABP in cellular organelles requires more evidence. The functional significance of the occurrence of more FABP types is unclear, in spite of the observed differences in their ligand-protein interaction.

Impaired free fatty acid utilization by skeletal muscle in non-insulin-dependent diabetes mellitus.

Abstract: This study was undertaken to assess utilization of FFA by skeletal muscle in patients with non-insulin-dependent diabetes mellitus (NIDDM). 11 NIDDM and 9 nondiabetic subjects were studied using leg balance methods to measure the fractional extraction of [3H]oleate. Limb indirect calorimetry was used to estimate RQ. Percutaneous muscle biopsy samples of vastus lateralis were analyzed for muscle fiber type distribution, capillary density, and metabolic potential as reflected by measurements of the activity of seven muscle enzyme markers of glycolytic and aerobic-oxidative pathways. During postabsorptive conditions, fractional extraction of oleate across the leg was lower in NIDDM subjects (0.31 +/- 0.08 vs. 0.43 +/- 0.10, P < 0.01), and there was reduced oleate uptake across the leg (66 +/- 8 vs. 82 +/- 13 nmol/min, P < 0.01). Postabsorptive leg RQ was increased in NIDDM (0.85 +/- 0.03 vs. 0.77 +/- 0.02, P < 0.01), and rates of lipid oxidation by skeletal muscle were lower while glucose oxidation was increased (P < 0.05). In subjects with NIDDM, proportions of type I, IIa, and IIb fibers were 37 +/- 2, 37 +/- 6, and 26 +/- 5%, respectively, which did not differ from nondiabetics; and capillary density, glycolytic, and aerobic-oxidative potentials were similar. During 6 h after ingestion of a mixed meal, arterial FFA remained greater in NIDDM subjects. Therefore, despite persistent reduced fractional extraction of oleate across the leg in NIDDM (0.34 +/- 0.04 vs. 0.38 +/- 0.03, P < 0.05), rates of oleate uptake across the leg were greater in NIDDM (54 +/- 7 vs. 45 +/- 8 nmol/min, P < 0.01). In summary, during postabsorptive conditions there is reduced utilization of FFA by muscle, while during postprandial conditions there is impaired suppression of FFA uptake across the leg in NIDDM. During both fasting and postprandial conditions, NIDDM subjects have reduced rates of lipid oxidation by muscle.

New insights into the structure and function of fatty acid-binding proteins.

Abstract: Fatty acid-binding proteins (FABPs) are members of a superfamily of lipid-binding proteins, and occur intracellularly in vertebrates and invertebrates. This review presents recent findings on the diversity of these FABPs and their proposed roles in fatty acid (FA) metabolism and other cellular processes. Special attention is paid to the structural features of the different mammalian FABP types and the physiological role of these proteins in FA transport, cell growth and differentiation, cellular signalling, gene transcription and cytoprotection. Additionally, data on FABP knockout mice and the implication of FABP in medicine are discussed.

Lipid-Binding Proteins: A Family of Fatty Acid and Retinoid Transport Proteins

Abstract: Publisher Summary This chapter focuses on the structural analyses and comparisons between members of a multigene family of hydrophobic ligand-binding proteins. It discusses the structural motif, general characteristics of the binding cavity, ligand entry, and the portal hypothesis and provides a detailed comparison of intra- and extracellular lipid binding proteins with known crystal structures. The members of this family are referred as lipid-binding proteins (LBPs). This collection of proteins can be subdivided into two groups: the intracellular lipid-binding protein family (iLBP) and the extracellular lipid binding protein family (eLBP). The comparison primarily deals with the iLBP branch because this family is becoming structurally well characterized. However, the structural comparisons are extended to some members of the eLBP family because the basic structural motif used to bind hydrophobic ligands applies to both. The products of hydrolysis of the intestinal lipids, including fatty acids, cholesterol, monoglycerides, and lysophospholipids, have very low solubilities and are absorbed by biliary micelles in the gut. These micelles diffuse through the glycocalyx, which stabilizes an unstirred water layer at the surface of the enterocyte. The chapter concludes with a discussion of the results of site-directed mutagenesis studies, the thermodynamics of lipid binding, and considerations of protein stability and folding.