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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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Epigenetic Proteins as Targets for Protection and Repair in the CNS: HDACS And Beyond

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Dr. Rishabh Pathak

Epigenetic proteins, including histone deacetylases (HDACs) and other chromatin-modifying enzymes, have emerged as promising targets for protection and repair in the central nervous system (CNS). By regulating gene expression through modifications of chromatin structure, these epigenetic regulators play critical roles in neuronal development, plasticity, and response to injury. Here is an overview of how HDACs and other epigenetic proteins can be targeted for neuroprotection and repair in the CNS:


1.      HDAC Inhibition for Neuroprotection:

o    Enhanced Synaptic Plasticity: HDAC inhibitors have been shown to promote synaptic plasticity and improve cognitive function by modulating gene expression related to memory formation and neuronal connectivity.

o    Neuroprotection Against Excitotoxicity: Inhibition of specific HDAC isoforms can protect neurons from excitotoxic damage by regulating the expression of genes involved in cell survival and stress response pathways.

o Promotion of Neuronal Survival: HDAC inhibitors have demonstrated neuroprotective effects by enhancing neuronal survival, reducing apoptosis, and modulating inflammatory responses in various neurodegenerative conditions.

2.     Beyond HDACs: Targeting Other Epigenetic Proteins:

o  DNA Methyltransferases (DNMTs): Inhibitors of DNMTs have shown potential for promoting neuroprotection and cognitive function by modulating DNA methylation patterns associated with gene expression in the CNS.

o    Histone Methyltransferases and Demethylases: Modulation of histone methylation dynamics by targeting histone methyltransferases and demethylases can influence neuronal differentiation, synaptic plasticity, and neuroprotection in the CNS.

o    Bromodomain and Extraterminal (BET) Proteins: Inhibition of BET proteins has been linked to neuroprotection and cognitive enhancement through regulation of gene expression programs involved in neuronal function and plasticity [T7].

3.     Therapeutic Implications:

o Precision Epigenetic Therapies: Targeting specific epigenetic proteins, such as HDAC isoforms or other chromatin modifiers, with selective inhibitors or activators holds promise for developing precision therapies tailored to different neurodegenerative disorders [T8].

o Combination Therapies: Combinatorial approaches involving multiple epigenetic targets, along with traditional neuroprotective strategies, may offer synergistic benefits for enhancing CNS protection and repair in complex neurological conditions [T9].

o    Personalized Medicine: Understanding the epigenetic signatures and chromatin landscapes associated with individual CNS pathologies can guide the development of personalized epigenetic interventions for optimizing neuroprotection and repair outcomes [T10].

In conclusion, targeting epigenetic proteins, including HDACs and beyond, presents a novel avenue for promoting neuroprotection and repair in the CNS. By modulating chromatin dynamics and gene expression patterns, these interventions hold potential for mitigating neurodegenerative processes, enhancing neuronal resilience, and fostering recovery in neurological disorders.

 

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