In silico identification of microRNAs potentially regulating aquaporin-4, a core component of glymphatic system physiology

Abstract

The glymphatic system is a brain-wide clearance pathway that facilitates cerebrospinal fluid–interstitial fluid exchange and metabolic waste removal, a process critically dependent on aquaporin-4 (AQP4) polarization at astrocytic perivascular endfeet. Disruption of AQP4 expression or localization has been associated with impaired glymphatic flow, contributing to cerebral edema, neuroinflammation, and neurodegenerative processes. Despite the central role of AQP4 in glymphatic physiology, the post-transcriptional regulatory mechanisms controlling its expression remain incompletely defined. In this study, we performed an in silico analysis to identify microRNAs (miRNAs) that may regulate AQP4 expression and thereby influence glymphatic system function. Using an intersection-based bioinformatics strategy, miRNA target prediction was conducted with TargetScan and miRDB to minimize algorithm-dependent bias. High-confidence candidate miRNAs were subsequently subjected to supportive validation using miRWalk, with a focus on canonical 3′ untranslated region (3′UTR) interactions. Five miRNAs (miR-28-3p, miR-770-5p, miR-577, miR-582-5p, and miR-576-5p) were identified as potential post-transcriptional regulators of AQP4 based on dual-database prediction. Among these, miR-576-5p emerged as the most consistently supported candidate, exhibiting a predicted canonical binding site within the AQP4 3′UTR. This interaction suggests a plausible mechanism by which miRNA-mediated fine-tuning of AQP4 expression could modulate astrocytic water permeability and, consequently, glymphatic fluid dynamics. Our findings provide a prioritized set of miRNAs that may participate in the regulation of AQP4-dependent glymphatic function. By highlighting miR-576-5p as a candidate regulator, this study offers a mechanistic framework linking miRNA-mediated post-transcriptional control of AQP4 to glymphatic system physiology and lays the groundwork for future experimental validation in astrocyte-based and in vivo models.