Analysis of Exosomal miRNA and Hepatic mRNA Expression in the Dysregulation of Insulin Action in Perimenopausal Mice.

Introduction

The aim of present study was to evaluate the impact of perimenopause on insulin resistance. Specifically, insulin sensitivity was assessed in a perimenopausal mouse model treated with 4-vinylcyclohexene diepoxide (VCD), together with the changes in exosomal miRNA and hepatic mRNA expression profiles.

Methods

Homeostasis model assessment of insulin resistance (HOMA-IR) was utilized to assess the status of insulin resistance, and insulin action was evaluated during menopausal transition. RNA sequencing (RNA-seq) analysis was used to identify altered expression profiles of exosomal miRNAs and hepatic mRNAs. Differentially expressed miRNA (DEM)-differentially expressed gene (DEG) network analyses were also conducted. Furthermore, altered expression levels of these exosomal miRNAs and genes were validated in plasma exosomes and liver tissue of perimenopausal mice.

Results

HOMA-IR in VCD-treated mice was significantly increased, and hepatic glycogen was significantly decreased. Key exosomal miRNAs (miR-17-3p, miR-134-5p, miR-700-5p, and miR-6899-3p) and hepatic genes (G6pdx, Ptpn2, Lepr, Kras, and Braf) may be associated with impaired insulin signaling during perimenopause.

Conclusion

The perimenopausal period acts as a potential factor in introducing insulin resistance as evidenced by impaired insulin action and altered expression profiles of exosomal miRNAs and hepatic genes. The present study contributes to the understanding that abnormal cargos carried by plasma exosomes, such as miRNAs, may be related to altered expression of the corresponding genes in the liver and abnormal insulin response.