High-throughput sequencing analysis of placental tissue from pregnant women with gestational diabetes and gestational hypertension

In this study, transcriptome sequencing was conducted on placentas obtained from both normal pregnancies and pregnancies with GDM to investigate the molecular mechanisms underlying this condition. Placental tissue samples were immersed in ice-cold phosphate-buffered saline (PBS) to remove blood contamination. Sections with a thickness of 4 µm were cut from the block and stained with Hematoxylin and eosin (HE) staining. The resulting slides were examined and photographed under a light microscope (Olympus).The original sequencing data were subjected to sequencing analysis, resulting in the identification of 935 upregulated genes and 256 downregulated genes. The Kyoto Encyclopedia of Genes and Genomes and Gene Ontology analysis techniques on differential genes uncovered evidence suggesting that the phosphoinositide 3-kinase (PI3K) /Akt signaling pathway may contribute to the pathogenesis of GDM. Subsequent analysis indicated that the expression levels of MMP11, MMP12, MMP14, and MMP15, which are regulated by the PI3K/Akt pathway, were upregulated in the placentas of patients with GDM when compared to those of individuals with normal placental function. Additionally, our investigation into alternative splicing patterns revealed an increase in exon skipping alternative splicing of CSF3R in the placenta of patients with GDM compared to that in the control group. Overall design: Placental tissue samples were obtained from women with singleton term pregnancies who underwent caesarean delivery prior to the initiation of labor at the Affiliated Hospital of Jining Medical University (Jining, China) between March 2020 and December 2022. None of the participants had preexisting acute or chronic complications, such as chronic hypertension or disorders affecting glucose metabolism, and none were subjected to any dietary restrictions. In both the groups, placental delivery was followed by immediate sample collection.For the experimental sequencing method, three placentas from the normal control group and three placentas from the GDM group were selected for transcriptome analysis. Total RNA was extracted from these samples to compare the expression levels of differentially expressed genes (DEGs). Total RNA was extracted, and RNA quality was assessed. After the RNA samples were qualified, common transcriptome libraries were constructed, and Illumina NovaSeq 6000 was used for sequencing.