Biology subjects

Shcherbakova, O.

Publications and source records attributed to Shcherbakova, O..

3 recordsLinked to original sources

bioRxiv2026

Peripheral Metabolic Reprogramming Links TDP-43 Proteinopathy to Sleep Disruption

Sleep disruption is an early and prevalent feature of neurodegenerative disease, commonly attributed to neuronal circuit dysfunction or cell loss. However, sleep is tightly coupled to metabolic state, raising the possibility that systemic metabolic abnormalities contribute to disease-associated sleep phenotypes. Using Drosophila models of TDP-43 proteinopathy, we investigated whether peripheral metabolic dysfunction plays a causal role in sleep disruption. We show that TDP-43 expression induces a chronic, starvation-like metabolic state characterized by depletion of peripheral carbohydrate stores despite normal feeding. Restoration of sleep fails to correct these metabolic defects, whereas improving peripheral metabolic state robustly rescues sleep. A modifier screen of [~]650 RNAi lines identified Salt-inducible kinase 3 (SIK3) as a potent suppressor of both sleep loss and starvation sensitivity. Transcriptomic and spatial metabolomic analyses reveal that SIK3 selectively remodels a peripheral metabolic program centered on the pentose phosphate pathway and redox-associated metabolites without globally restoring energy stores. Together, these findings identify systemic metabolic dysfunction as a key driver of sleep disruption in TDP-43 proteinopathy and highlight peripheral metabolism as a potential therapeutic entry point for sleep dysfunction in neurodegenerative disease.

neuroscience↗

bioRxiv2024

The chromatin conformation landscape of Alzheimer's disease

We have been investigating epigenetic alterations in the brain during human aging and Alzheimers disease (AD), and have evidence for histone acetylation both protecting the aging epigenome and driving AD. Here we extend our studies to chromatin architecture via looping studies, and with binding studies of key proteins required for looping: CTCF and RAD21. We detected changes in CTCF and RAD21 levels and localization, finding major changes in CTCF in AD compared to fewer changes in healthy aging. In our study of 3D genome conformation changes, we identified stable topological associating domains (TADs) in Old and AD; in contrast, in AD, there is loss of interaction at genomic sites/loops within TADs, likely reflecting the loss of CTCF. We identified genes and potential transcription factor binding at the loops that are lost in AD. in addition, we found enrichment of CTCF peak losses for AD eQTLs, suggesting that architectural dysfunction has a role in Alzheimers. Functional experiments lowering the homologues of several key genes in a Drosophila model of A{beta}42 toxicity exacerbate neurodegeneration. Taken together, these data indicate both functional protections and losses occur in the Alzheimers brain genome compared to normal aging.

neuroscience↗

bioRxiv2024

ACSS2 upregulation enhances neuronal resilience to aging and tau-associated neurodegeneration

Epigenetic mechanisms, including histone acetylation, are pivotal for learning and memory, with a role in neuronal function in Alzheimers disease and Related Dementia (ADRD). Acetyl-CoA synthetase 2 (ACSS2), an enzyme that generates acetyl-CoA, is central to histone acetylation and gene regulation, particularly in neurons, due to their unique metabolic demands and postmitotic state. ACSS2 can be recruited to the nucleus and chromatin, locally supplying acetyl-CoA to directly fuel histone acetyltransferase enzymes and key neuronal gene expression. This regulatory mechanism may be a promising target for therapeutic intervention in neurodegenerative diseases. Previously we showed that systemic ACSS2 deletion in mice, although largely normal in physiology, is greatly impaired in memory. Here we investigated whether increasing ACSS2 levels could protect neurons against disease and age-associated cognitive decline. Given the role of tau in ADRD, we used primary hippocampal neurons that mimic the sporadic development of tau pathology and the P301S transgenic mouse model for tau-induced memory decline. Our results show that ACSS2 upregulation mitigates tau-induced transcriptional alterations, enhances neuronal resilience against tau pathology, improves long-term potentiation, and ameliorates memory deficits. Expanding upon these findings, we reveal that increasing histone acetylation through ACSS2 upregulation improves age-associated memory decline. These findings indicate that increasing ACSS2 is highly effective in countering age- and tau-induced transcriptome changes, preserving elevated levels of synaptic genes, and safeguarding synaptic integrity. We thus highlight ACSS2 as a key player in the epigenetic regulation of cognitive aging and ADRD, providing a foundation for targeted therapeutics to enhance brain resilience and function. SummaryACSS2 upregulation protects neurons from disease and age-related decline by enhancing synaptic and longevity gene expression.

neuroscience↗