Microarray Analysis of Differentially Expressed Genes in Peripheral Blood of Postpartum Women with Gestational Diabetes Mellitus and Type 2 Diabetes

The etiology of women with gestational diabetes mellitus (GDM) and a greater risk of developing type 2 diabetes (T2D) after delivery remains unknown. This study aimed to investigate the global gene expression in four postpartum women with previous GDM (pGDM), three with T2D, and three with a history of normoglycemic pregnancy (controls). Total RNA was extracted from whole blood between March and May 2020. Global mRNA expression was determined using an Affymetrix Human Gene 2.0 ST Array. The expression of the selected focused genes was validated by RT-PCR. The microarray revealed 140 transcripts (p < 0.05, fold change cut-off ≥ 2) in patients with pGDM compared to controls. We identified 583 gene-altered transcripts between patients with T2D and controls. Interestingly, 60 transcripts had genes shared by pGDM or T2D versus the controls. The selected upregulated genes involved in inflammatory response, glycosylation, and death-like domains, according to the functional network analysis of pGDM (TNFAIP6, PDK3) and T2D (MMP9 and CARD6), showed similar trends to those obtained via microarray. Thus, these differentially expressed genes and their corresponding network and pathway analyses in women with pGDM and T2D offer valuable insights into the possible biological mechanisms of the progression of GDM to T2D.