A transcriptomic study reveals beneficial effects of HsTX1[R14A] on the cognition of a mouse model of sporadic Alzheimer’s disease

Abstract Background Neuroinflammation is a key pathological feature of Alzheimer’s disease (AD), which can be partly attributed to the chronic activation of microglia. The voltage‐gated potassium channel 1.3 (Kv1.3) is selectively upregulated in pro‐inflammatory microglia, making it an ideal therapeutic target to modulate microglia‐mediated neuroinflammation. A highly potent and selective Kv1.3 blocker (HsTX1[R14A]) developed in our laboratory can effectively suppress neuroinflammation. More importantly, chronic subcutaneous dosing of HsTX1[R14A] (1 mg/kg every 2 day) over 8 weeks improved cognitive function in a mouse model of sporadic AD, senescence accelerated mouse‐prone 8 (SAMP8). The current transcriptomic study is to explore the therapeutic benefits in the SAMP8 mouse brains from chronic dosing of HsTX1[R14A]. Method Subcutaneous dose of HsTX1[R14A] (1mg/kg every 2 day) or PBS was administered to 4‐month‐old SAMP8 mice for 8 weeks (n = 6 each). At the conclusion of treatment, mice were euthanized and RNA from the brains were extracted using RNeasy Lipid Tissue Mini Kit (Qiagen). RNA samples were processed using an MGI RNA Directional Library Preparation Set V2. Fastq files were processed using the Laxy tool and the NfCore/RNAseq (v3.2) pipeline. Reads were aligned to the Mus musculus GRCm38 reference using STAR aligner and quantified using Salmon producing the raw genes count matrix. Raw counts were then analyzed with Degust and functional enrichment analysis was performed using R packages. Result Functional enrichment analysis indicated an upregulation of genes associated with 1) synapse assembly, neuronal synaptic plasticity for biological process; 2) postsynaptic neurotransmitter receptor activity, glutamate receptor activity for molecular function; 3) presynaptic active zone, NMDA selective glutamate receptor complex for cellular component. A downregulation of genes associated with 1) oxidative phosphorylation, ATP synthesis coupled electron transport for biological process; 2) chemokine activity for molecular function; 3) mitochondrial proton transporting ATP synthase complex for cellular component have also been highlighted. Conclusion Overall, the transcriptomics data indicated beneficial effects of HsTX1[R14A] on cognition in a mouse model of sporadic AD, possibly achieved by improving synaptic function, altering cellular metabolism, and reducing inflammation. Further experiments are required to confirm the current transcriptomics study.