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Buckingham, S. C.

Publications and source records attributed to Buckingham, S. C..

2 recordsLinked to original sources

Excitoprotective effects of conditional tau reduction in excitatory neurons and in adulthood

Tau reduction is a promising therapeutic strategy for Alzheimers disease. In numerous models, tau reduction via genetic knockout is beneficial, at least in part due to protection against hyperexcitability and seizures, but the underlying mechanisms are unclear. Here we describe the generation and initial study of a new conditional Tauflox model to address these mechanisms. Given the protective effects of tau reduction against hyperexcitability, we compared the effects of selective tau reduction in excitatory or inhibitory neurons. Tau reduction in excitatory neurons mimicked the protective effects of global tau reduction, while tau reduction in inhibitory neurons had the opposite effect and increased seizure susceptibility. Since most prior studies used knockout mice lacking tau throughout development, we crossed Tauflox mice with inducible Cre mice and found beneficial effects of tau reduction in adulthood. Our findings support the effectiveness of tau reduction in adulthood and indicate that excitatory neurons may be a key site for its excitoprotective effects. SUMMARYA new conditional tau knockout model was generated to study the protective effects of tau reduction against hyperexcitability. Conditional tau reduction in excitatory, but not inhibitory, neurons was excitoprotective, and induced tau reduction in adulthood was excitoprotective without adverse effects.

neuroscience↗

Human and Rodent Temporal Lobe Epilepsy is Characterized by Changes in O-GlcNAc Homeostasis that can be Reversed to Dampen Epileptiform Activity

Temporal Lobe Epilepsy (TLE) is frequently associated with changes in protein composition and post-translational modifications (PTM) that exacerbate the disorder. O-linked-{beta}-N-acetyl glucosamine (O-GlcNAc) is a PTM occurring at serine/threonine residues that integrate energy supply with demand. The enzymes O-GlcNActransferase (OGT) and O-GlcNAcase (OGA) mediate the addition and removal, respectively, of the O-GlcNAc modification. The goal of this study was to determine whether changes in OGT/OGA cycling and disruptions in protein O-GlcNAcylation occur in the epileptic hippocampus. We observed reduced global and protein specific O-GlcNAcylation and OGT expression in the kainate rat model of TLE and in human TLE hippocampal tissue. Inhibiting OGA with Thiamet-G elevated protein O-GlcNAcylation, and decreased both seizure duration and epileptic spike events, suggesting that OGA may be a therapeutic target for seizure control. These findings suggest that loss of O-GlcNAc homeostasis in the kainate model and in human TLE can be reversed via targeting of O-GlcNAc related pathways.

neuroscience↗