title: Perineuronal nets potentially protect against oxidative stress.
abstract: A specialized form of extracellular matrix (ECM) termed perineuronal nets (PNs) consisting of large aggregating chondroitin sulfate proteoglycans (CSPGs), with hyaluronan and tenascin as main components, surrounds subpopulations of neurons. The glycosaminoglycan components of perineuronal nets form highly charged structures in the direct microenvironment of neurons and thus might be involved in local ion homeostasis. The polyanionic character suggests that perineuronal nets also potentially contribute to reduce the local oxidative potential in the neuronal microenvironment by scavenging and binding redox-active iron, thus providing some neuroprotection to net-associated neurons. Here, we show that neurons ensheathed by a perineuronal net in the human cerebral cortex are less frequently affected by lipofuscin accumulation than neurons without a net both in normal-aged brain and Alzheimer's disease (AD). As lipofuscin is an intralysosomal pigment composed of cross-linked proteins and lipids generated by iron-catalyzed oxidative processes, the present results suggest a neuroprotective function of perineuronal nets against oxidative stress, potentially involved in neurodegeneration.
authors.affiliation: Department of Neuroanatomy, Paul Flechsig Institute for Brain Research, University of Leipzig, Jahnallee 59, D-04109, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Morawski
authors.forename: Martina K
authors.initials: MK
authors.lastname: Brückner
authors.forename: Peter
authors.initials: P
authors.lastname: Riederer
authors.forename: Gert
authors.initials: G
authors.lastname: Brückner
authors.forename: Thomas
authors.initials: T
authors.lastname: Arendt
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000378:metabolism* / Q000473:pathology; D002452:Cell Count; D002540:Cerebral Cortex / Q000378:metabolism / Q000473:pathology; D005109:Extracellular Matrix / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008062:Lipofuscin / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009474:Neurons / Q000378:metabolism* / Q000473:pathology; D018384:Oxidative Stress; D017966:Pyramidal Cells / Q000378:metabolism / Q000473:pathology
chemical_list: D008062:Lipofuscin