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Heller, H. C.

Publications and source records attributed to Heller, H. C..

2 recordsLinked to original sources

Inhibiting USP16 rescues stem cell aging and memory in an Alzheimer's model

Alzheimers disease (AD) is a progressive neurodegenerative disease observed with aging that represents the most common form of dementia. To date, therapies targeting end-stage disease plaques, tangles, or inflammation have limited efficacy. Therefore, we set out to identify an earlier targetable phenotype. Utilizing a mouse model of AD and human fetal cells harboring mutant amyloid precursor protein, we show cell intrinsic neural precursor cell (NPC) dysfunction precedes widespread inflammation and amyloid plaque pathology, making it the earliest defect in the evolution of disease. We demonstrate that reversing impaired NPC self-renewal via genetic reduction of USP16, a histone modifier and critical physiological antagonist of the Polycomb Repressor Complex 1, can prevent downstream cognitive defects and decrease astrogliosis in vivo. Reduction of USP16 led to decreased expression of senescence gene Cdkn2a and mitigated aberrant regulation of the BMP pathway, a previously unknown function of USP16. Thus, we reveal USP16 as a novel target in an AD model that can both ameliorate the NPC defect and rescue memory and learning through its regulation of both Cdkn2a and BMP signaling. Graphical Abstract O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY Schematic summarizing therapeutic approaches to mitigate the effects of mutant APP through targeting of Cdkn2a, BMI1, USP16 and BMP.

molecular biology

Disordered phasic relationships between hippocampal place cells, theta, and gamma rhythms in the Ts65Dn mouse model of Down Syndrome

Down Syndrome (DS) in humans is caused by trisomy of chromosome 21 and is marked by prominent difficulties in learning and memory. Decades of research have demonstrated that the hippocampus is a key structure in learning and memory, and recent work with mouse models of DS have shown changes in spectral coherence in the field potentials of hippocampus and regions important for executive function such as prefrontal cortex. One of the primary functional differences in DS is thought to be an excess of GABAergic innervation from Medial Septum (MS) to regions such as hippocampus. In these experiments, we probe in detail the activity of region CA1 of the hippocampus using in vivo electrophysiology in the Ts65Dn mouse model of DS in comparison to their non-trisomic 2N littermates. We find changes in hippocampal phenomenology that suggest that MS output, which drives theta rhythm in the hippocampus, is strongly altered. Moreover, we find that this change affects the phasic relationship of both CA1 place cells and gamma rhythms to theta. Since the phasic relationship of both of these aspects of hippocampal phenomenology to theta are thought to be critical for the segregation of encoding and retrieval epochs within hippocampus, it is likely that these changes are the neural substrates of the learning and memory deficits seen both in human DS and animal models such as Ts65Dn.

neuroscience