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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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Neuronal Precursor Proliferation Is Enhanced by Cannabinoids Via CB1/AKT/GSK- 3BETA/BETA-Catenin Signaling

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Dr. Rishabh Pathak

The proliferation of neuronal precursors is enhanced by cannabinoids through a signaling pathway involving CB1 receptors, AKT, GSK-3beta, and beta-catenin. Here is a breakdown of the key points related to this mechanism:

1.      Cannabinoids and Neuronal Precursor Proliferation:

o Cannabinoids, including endocannabinoids and exogenous cannabinoids, have been shown to promote the proliferation of neuronal precursor cells in the brain.

o   This effect of cannabinoids on neuronal precursor proliferation is of interest for potential therapeutic applications in neuroregeneration and brain repair.

2.     CB1 Receptors:

o   Cannabinoid receptor type 1 (CB1) is a G protein-coupled receptor that is abundantly expressed in the brain, including regions involved in neurogenesis.

o  Activation of CB1 receptors by cannabinoids initiates intracellular signaling cascades that regulate various cellular processes, including neuronal precursor proliferation.

3.     AKT Signaling Pathway:

o  AKT, also known as protein kinase B, is a key signaling molecule involved in cell survival, proliferation, and growth.

o    Activation of CB1 receptors by cannabinoids can stimulate the AKT signaling pathway, leading to the activation of downstream effectors that promote neuronal precursor proliferation.

4.    GSK-3beta and Beta-Catenin:

o   Glycogen synthase kinase-3 beta (GSK-3beta) is a serine/threonine kinase that regulates various cellular functions, including cell proliferation and differentiation.

o  In the context of neuronal precursor proliferation, GSK-3beta is known to phosphorylate beta-catenin, a transcriptional co-activator involved in cell proliferation and survival.

o   Activation of AKT by CB1 receptor signaling can inhibit GSK-3beta activity, leading to the stabilization and accumulation of beta-catenin in the nucleus.

5.     CB1/AKT/GSK-3beta/Beta-Catenin Signaling:

o The CB1/AKT/GSK-3beta/beta-catenin signaling pathway represents a mechanism through which cannabinoids enhance the proliferation of neuronal precursor cells.

o  Activation of CB1 receptors by cannabinoids triggers a cascade of events that ultimately result in the activation of AKT, inhibition of GSK-3beta, and nuclear translocation of beta-catenin, promoting cell proliferation.

6.    Therapeutic Implications:

o  Understanding the molecular mechanisms underlying the effects of cannabinoids on neuronal precursor proliferation can inform the development of novel therapeutic strategies for promoting neurogenesis and brain repair in various neurological conditions.

o  Targeting the CB1/AKT/GSK-3beta/beta-catenin pathway may offer potential therapeutic opportunities for enhancing neuroregeneration and functional recovery in the brain.

In summary, cannabinoids enhance neuronal precursor proliferation through the CB1/AKT/GSK-3beta/beta-catenin signaling pathway, highlighting the potential of cannabinoid-based therapies for promoting neurogenesis and brain repair.

 

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