A role for apolipoprotein E, apolipoprotein A-I, and low density lipoprotein receptors in cholesterol transport during regeneration and remyelination of the rat sciatic nerve
Abstract
Recent work has demonstrated that apo E secretion and accumulation increase in the regenerating peripheral nerve. The fact that apoE, in conjunction with apoA-I and LDL receptors, participates in a well-established lipid transfer system raised the possibility that apoE is also involved in lipid transport in the injured nerve. In the present study of the crushed rat sciatic nerve, a combination of techniques was used to trace the cellular associations of apoE, apoA-I, and the LDL receptor during nerve repair and to determine the distribution of lipid at each stage. After a crush injury, as axons died and Schwann cells reabsorbed myelin, resident and monocyte-derived macrophages produced large quantities of apoE distal to the injury site. As axons regenerated in the first week, their tips contained a high concentration of LDL receptors. After axon regeneration, apoE and apoA-I began to accumulate distal to the injury site and macrophages became increasingly cholesterol-loaded. As remyelination began in the second and third weeks after injury, Schwann cells exhausted their cholesterol stores, then displayed increased LDL receptors. Depletion of macrophage cholesterol stores followed over the next several weeks. During this stage o...Continue Reading
References
Citations
Post-translational modifications of apolipoprotein A-I and Po proteins in the avian peripheral nerve
Neuropathology after active Abeta42 immunotherapy: implications for Alzheimer's disease pathogenesis
Exogenous glucocorticoids increase macrophage secretion of apo E by cholesterol-independent pathways
Related Concepts
Related Feeds
ApoE, Lipids & Cholesterol
Serum cholesterol, triglycerides, apolipoprotein B (APOB)-containing lipoproteins (very low-density lipoprotein (VLDL), immediate-density lipoprotein (IDL), and low-density lipoprotein (LDL), lipoprotein A (LPA)) and the total cholesterol/high-density lipoprotein (HDL) cholesterol ratio are all connected in diseases. Here is the latest research.
Cell Biology of Lipids
Lipids are essential in many biological functions, including membrane structure, energy storage, and cell signaling. Find the latest research on the cell biology of lipids here.
ApoE Phenotypes
Apolipoprotein E (APOE) is a protein involved in fat metabolism and associated with the pathogenesis of Alzheimer's disease and cardiovascular disease. Here is the latest research on APOE phenotypes.