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Unveiling Hidden Neural Codes: SIMPL – A Scalable and Fast Approach for Optimizing Latent Variables and Tuning Curves in Neural Population Data

Dr. Rishabh Pathak
This research paper presents SIMPL (Scalable Iterative Maximization of Population-coded Latents), a novel, computationally efficient algorithm designed to refine the estimation of latent variables and tuning curves from neural population activity. Latent variables in neural data represent essential low-dimensional quantities encoding behavioral or cognitive states, which neuroscientists seek to identify to understand brain computations better. Background and Motivation Traditional approaches commonly assume the observed behavioral variable as the latent neural code. However, this assumption can lead to inaccuracies because neural activity sometimes encodes internal cognitive states differing subtly from observable behavior (e.g., anticipation, mental simulation). Existing latent variable models face challenges such as high computational cost, poor scalability to large datasets, limited expressiveness of tuning models, or difficulties interpreting complex neural network-based functio...
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Acetylation status during neurodegeneration, memory functions and aging: use of epigenetic modulators in Alzheimer’s diseases?

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Dr. Rishabh Pathak

Acetylation status, particularly histone acetylation, plays a crucial role in regulating gene expression, synaptic plasticity, memory functions, and neurodegenerative processes in the context of aging and Alzheimer's disease (AD). Epigenetic modulators, including histone acetyltransferases (HATs) and histone deacetylases (HDACs), can dynamically regulate acetylation levels and impact neuronal function. Here is an overview of the acetylation status during neurodegeneration, memory functions, aging, and the potential use of epigenetic modulators in Alzheimer's disease:


1.      Acetylation Status in Neurodegeneration:

o    Altered Histone Acetylation:

§  Neurodegenerative diseases, including AD, are associated with dysregulation of histone acetylation patterns, leading to aberrant gene expression and neuronal dysfunction.

§  Changes in histone acetylation levels can influence the expression of genes involved in neuroinflammation, oxidative stress, protein aggregation, and synaptic impairment.

o    Role of HDACs:

§  Overactivity of HDACs in neurodegenerative conditions can result in chromatin condensation, transcriptional silencing of neuroprotective genes, and exacerbation of disease pathology.

§  Targeting HDACs with specific inhibitors has emerged as a potential therapeutic strategy to restore histone acetylation balance and mitigate neurodegeneration-associated processes.

2.     Acetylation Status in Memory Functions:

o    Synaptic Plasticity and Memory Formation:

§  Histone acetylation dynamics play a critical role in regulating synaptic plasticity mechanisms, such as long-term potentiation (LTP) and long-term memory formation.

§  Acetylation of histones at specific gene loci involved in memory consolidation and synaptic strength is essential for proper cognitive function.

o    Epigenetic Regulation of Memory:

§  Epigenetic modulators, including HATs and HDACs, modulate the acetylation status of histones and non-histone proteins, influencing memory processes and cognitive performance.

3.     Acetylation Status in Aging:

o    Age-Related Changes in Acetylation:

§  Aging is associated with alterations in histone acetylation patterns, impacting gene expression profiles, cellular senescence, and cognitive decline.

§  Dysregulation of acetylation status during aging can contribute to neurodegenerative changes, synaptic dysfunction, and memory deficits.

o    Potential Role of Epigenetic Modulators:

§  Modulating histone acetylation through epigenetic modulators may offer a strategy to counteract age-related epigenetic alterations, enhance cognitive function, and promote healthy brain aging.

4.    Use of Epigenetic Modulators in Alzheimer's Disease:

o    Therapeutic Potential:

§  Epigenetic modulators, such as HDAC inhibitors, have shown promise in preclinical studies and clinical trials for AD by targeting aberrant histone acetylation patterns and gene expression changes.

§  Restoring histone acetylation balance with epigenetic modulators may help alleviate neurodegenerative processes, enhance synaptic plasticity, and improve memory functions in AD patients.

In summary, understanding the acetylation status during neurodegeneration, memory functions, and aging provides insights into the molecular mechanisms underlying these processes. Utilizing epigenetic modulators, particularly those targeting histone acetylation, holds therapeutic potential for addressing epigenetic dysregulation in Alzheimer's disease and other age-related cognitive disorders. Further research into the specific mechanisms of acetylation regulation and the development of targeted epigenetic therapies may offer new avenues for treating neurodegenerative diseases and age-related cognitive decline.

 

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