A role for lipoprotein lipase during synaptic remodeling in the adult mouse brain.
Lipoprotein lipase (LPL) is a member of a lipase family known to hydrolyze triglyceride molecules found in lipoprotein particles. This particular lipase also has a role in the binding of lipoprotein particles to different cell-surface receptors. LPL has been identified in the brain but has no specific function yet. This study aimed at elucidating the role of LPL in the brain in response to injury. Mice were subjected to hippocampal deafferentation using the entorhinal cortex lesion and mRNA and protein expression were assessed over a time-course of degeneration/reinnervation. Hippocampal LPL levels peaked at 2 days post-lesion (DPL) both at the mRNA and protein levels. No change was observed for receptors of the LDL-receptor family or RAP at DPL 2 in the hippocampus but the glia-specific syndecan-4 was found to be significantly upregulated at DPL 2. These results suggest that LPL is involved in the recycling of cholesterol and lipids released from degenerating terminals after a lesion through a syndecan-4-dependent pathway.
Blain
Jean-François
JF
Department of Anatomy and Physiology, Faculty of Medicine, Laval University, Ste-Foy, Quebec, Canada.
Paradis
Eric
E
Gaudreault
Sophie B
SB
Champagne
Danielle
D
Richard
Denis
D
Poirier
Judes
J
D000818:Animals; D001057:Apolipoproteins E / Q000378:metabolism; D001930:Brain Injuries / Q000201:enzymology* / Q000473:pathology; D015180:Electrophoresis, Gel, Two-Dimensional; D015151:Immunoblotting; D017403:In Situ Hybridization; D008071:Lipoprotein Lipase / Q000096:biosynthesis*; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism; D051379:Mice; D009410:Nerve Degeneration / Q000201:enzymology* / Q000473:pathology; D009416:Nerve Regeneration / Q000502:physiology; D011509:Proteoglycans / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D011973:Receptors, LDL / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013569:Synapses / Q000201:enzymology*; D053671:Syndecan-4
D001057:Apolipoproteins E; D008562:Membrane Glycoproteins; D011509:Proteoglycans; D012333:RNA, Messenger; D011973:Receptors, LDL; C508306:Sdc4 protein, mouse; D053671:Syndecan-4; D008071:Lipoprotein Lipase