Sato K, Tobo M, Mogi C, Murata N, Kotake M, Okajima F (IMCR, Gunma Univ.) Im DS (College of Pharmacy. Pusan National Univ.) Kuwabara A (Faculty of Heath Care, Takasaki Univ. of Health and Welfare)
About
Oxidatively damaged proteins and lipid peroxidation products have been shown to accumulate in the brain of neurodegenerative diseases, such as Alzheimer’s disease and multiple sclerosis, and oxidized lipoprotein is considered to be toxic and neurodegenerative. However, the role of lipoprotein and its oxidized form in neurite remodeling has not been well understood. In the present study, we have aimed to clarify whether and, if so, how high-density lipoprotein (HDL) and oxidized HDL (oxHDL) affect neuritegenesis. In the presence of nerve growth factor, exposure of PC12 cells to either HDL or oxHDL induces a rapid neurite retraction, which is followed by re-outgrowth of neurites in either case; however, oxHDL-treated cells exhibit much longer outgrowths than do basal and HDL-treated cells. Thus, processes in the morphological changes of neuronal cells after lipoprotein treatment are composed of two phases: the reversible retraction phase and the extension phase. Characterization of the active fractions of lipids and experiments with desensitization and knockdown of receptors have indicated that the reversible retraction phase involves mainly sphingosine 1-phosphate for HDL and lysophosphatidic acid for oxHDL. The change in the components responsible for the retraction response is comparable with the change in sphingosine 1-phosphate and lysophosphatidic acid contents by the oxidation of HDL. In the extension phase, lysophosphatidylcholine, which is increased by the oxidation of HDL, may play a stimulatory role in neurite outgrowth. We conclude that lipoprotein and its oxidized form differentially regulate neuritogenesis through lipoprotein-associated lysolipid molecules.
Paper information
Lipoprotein-associated lysolipid molecules are differentially involved in high-density lipoprotein- and its oxidized form-induced neurite remodeling in PC12 cells.
Sato K, Tobo M, Mogi C, Murata N, Kotake M, Kuwabara A, Im DS, Okajima F.
Neurochem Int. 68: 38-47, 2014
Online URL
http://www.ncbi.nlm.nih.gov/pubmed/24589770
