PAK1 as a Potential Functional Target of Seminal Plasma Exosomal miR‐7‐5p in Asthenozoospermia
Chunhui Liu, Wensheng Shan, Zhiqiang Wang, Shaojun Li, Ruipeng WuBackground
Seminal plasma exosomes carry microRNAs (miRNAs) implicated in sperm function. Although miR‐7‐5p has been reported to be upregulated in asthenozoospermia (AZS), its downstream targets and diagnostic value remain incompletely defined.
Method
To investigate p21‐activated kinase 1 ( PAK1 ) as a potential target of seminal plasma exosomal miR‐7‐5p and its possible involvement in sperm motility regulation, and to preliminarily evaluate the combined diagnostic value of miR‐7‐5p and PAK1 in AZS.
Materials and Methods
A total of 80 patients with AZS and 80 healthy controls (HCs) were enrolled. Seminal plasma exosomes were isolated, characterized, and subjected to miRNA microarray and quantitative real‐time polymerase chain reaction (qRT‐PCR). Target genes were predicted bioinformatically and further examined by dual‐luciferase reporter assay. Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analyses, weighted gene coexpression network analysis (WGCNA), and receiver operating characteristic (ROC) analyses were performed.
Results
miR‐7‐5p was significantly upregulated in AZS exosomes, whereas PAK1 was downregulated (both p < 0.001). miR‐7‐5p was negatively correlated with PAK1 ( r = −0.532) and progressive motility (PR) ( r = −0.525), while PAK1 was positively correlated with PR ( r = 0.468) (all p < 0.001). Dual‐luciferase reporter assay provided evidence supporting PAK1 as a potential direct target of miR‐7‐5p. Pathway enrichment and WGCNA analyses suggested that PAK1 may act as a central node within the cytoskeletal and Rho GTPase/MAPK signaling networks. These findings are consistent with a potential model in which miR‐7‐5p may downregulate PAK1 , potentially interfering with Rho GTPase/MAPK‐mediated cytoskeletal dynamics and flagellar assembly, which may contribute to impaired sperm motility. In this preliminary cohort, combined detection of miR‐7‐5p and PAK1 yielded an area under the ROC curve (AUC) of 0.864 (sensitivity 80.4%, specificity 79.8%), which was higher than that of either marker alone.
Conclusions
Building on previous reports of miR‐7‐5p upregulation in AZS, this study provides preliminary evidence that PAK1 may be a downstream target and may be involved in impaired sperm motility, potentially through Rho GTPase/MAPK‐mediated cytoskeletal and flagellar dysfunction. Combined detection of miR‐7‐5p and PAK1 showed a higher AUC than either marker alone in this preliminary cohort; however, multicenter validation, comparison with standard semen analysis, and cost‐effectiveness analysis are required before clinical application. No therapeutic conclusion can be drawn.