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Biology subjects

Santos, E. C. S.

Publications and source records attributed to Santos, E. C. S..

2 recordsLinked to original sources

Increasing the vitamin C transporter SVCT2 in microglia improves synaptic plasticity and restrains memory impairments in Alzheimer's disease models

Alzheimers Disease (AD) is characterized by progressive cognitive decline and synaptic dysfunction, often associated with amyloid-beta accumulation and microglial alterations. Here, we investigate the role of the Sodium-dependent Vitamin C Transporter 2 (SVCT2) in microglia to modulate AD-like pathology in mice. Using a combination of RNA sequencing, advanced quantitative proteomics, electrophysiology, behavioral tests, high-throughput imaging, and microglial viral gene delivery, we explore the interplay between SVCT2 expression in microglia, amyloid-beta load, synaptic proteome changes, and synaptic plasticity. Our results demonstrate that SVCT2 expression in microglia decreases with age in the 5xFAD mice, correlating with memory deficits and alterations in synaptic mitochondrial proteome. Importantly, overexpression of SVCT2 in microglia leads to enhanced clearance of amyloid plaques and reconfiguration of the mitochondrial proteome landscape in the synapses, improving synaptic long-term plasticity (LTP) and memory performance. Our findings underscore the SVCT2 overexpression in microglia as a potent strategy to simultaneously decrease amyloid pathology and enhance synaptic plasticity and memory performance, offering new avenues for therapeutic interventions in AD.

neuroscience↗

Microglia remodel the synaptic signaling required for context-dependent cognitive performance

Microglial homeostatic functions are fundamental to regulate the central nervous system microenvironment. We use conditional cell-specific gene targeting, RNA-seq profiling, high-throughput proteomics, phosphoproteomics, systems biology, and animal behavior to report a critical role for the RhoGTPase Rac1 in regulating adult microglia physiology. Ablation of Rac1 in adult microglia impaired their ability to sense and interpret the brain microenvironment and affected their capacity to communicate with synapses to drive cognitive performance, both at the steady-state and during experience-dependent plasticity. Overall, our results reveal a novel and central role for Rac1 as a regulator of microglia homeostasis and a molecular driver of the microglia-synapse crosstalk required for context-dependent sociability and learning related to memory.

neuroscience↗